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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * NSA Security-Enhanced Linux (SELinux) security module
4 *
5 * This file contains the SELinux hook function implementations.
6 *
7 * Authors: Stephen Smalley, <sds@tycho.nsa.gov>
8 * Chris Vance, <cvance@nai.com>
9 * Wayne Salamon, <wsalamon@nai.com>
10 * James Morris <jmorris@redhat.com>
11 *
12 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
13 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
14 * Eric Paris <eparis@redhat.com>
15 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
16 * <dgoeddel@trustedcs.com>
17 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
18 * Paul Moore <paul@paul-moore.com>
19 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
20 * Yuichi Nakamura <ynakam@hitachisoft.jp>
21 * Copyright (C) 2016 Mellanox Technologies
22 */
23
24#include <linux/init.h>
25#include <linux/kd.h>
26#include <linux/kernel.h>
27#include <linux/tracehook.h>
28#include <linux/errno.h>
29#include <linux/sched/signal.h>
30#include <linux/sched/task.h>
31#include <linux/lsm_hooks.h>
32#include <linux/xattr.h>
33#include <linux/capability.h>
34#include <linux/unistd.h>
35#include <linux/mm.h>
36#include <linux/mman.h>
37#include <linux/slab.h>
38#include <linux/pagemap.h>
39#include <linux/proc_fs.h>
40#include <linux/swap.h>
41#include <linux/spinlock.h>
42#include <linux/syscalls.h>
43#include <linux/dcache.h>
44#include <linux/file.h>
45#include <linux/fdtable.h>
46#include <linux/namei.h>
47#include <linux/mount.h>
48#include <linux/fs_context.h>
49#include <linux/fs_parser.h>
50#include <linux/netfilter_ipv4.h>
51#include <linux/netfilter_ipv6.h>
52#include <linux/tty.h>
53#include <net/icmp.h>
54#include <net/ip.h> /* for local_port_range[] */
55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56#include <net/inet_connection_sock.h>
57#include <net/net_namespace.h>
58#include <net/netlabel.h>
59#include <linux/uaccess.h>
60#include <asm/ioctls.h>
61#include <linux/atomic.h>
62#include <linux/bitops.h>
63#include <linux/interrupt.h>
64#include <linux/netdevice.h> /* for network interface checks */
65#include <net/netlink.h>
66#include <linux/tcp.h>
67#include <linux/udp.h>
68#include <linux/dccp.h>
69#include <linux/sctp.h>
70#include <net/sctp/structs.h>
71#include <linux/quota.h>
72#include <linux/un.h> /* for Unix socket types */
73#include <net/af_unix.h> /* for Unix socket types */
74#include <linux/parser.h>
75#include <linux/nfs_mount.h>
76#include <net/ipv6.h>
77#include <linux/hugetlb.h>
78#include <linux/personality.h>
79#include <linux/audit.h>
80#include <linux/string.h>
81#include <linux/mutex.h>
82#include <linux/posix-timers.h>
83#include <linux/syslog.h>
84#include <linux/user_namespace.h>
85#include <linux/export.h>
86#include <linux/msg.h>
87#include <linux/shm.h>
88#include <linux/bpf.h>
89#include <linux/kernfs.h>
90#include <linux/stringhash.h> /* for hashlen_string() */
91#include <uapi/linux/mount.h>
92#include <linux/fsnotify.h>
93#include <linux/fanotify.h>
94
95#include "avc.h"
96#include "objsec.h"
97#include "netif.h"
98#include "netnode.h"
99#include "netport.h"
100#include "ibpkey.h"
101#include "xfrm.h"
102#include "netlabel.h"
103#include "audit.h"
104#include "avc_ss.h"
105
106struct selinux_state selinux_state;
107
108/* SECMARK reference count */
109static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
110
111#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
112static int selinux_enforcing_boot __initdata;
113
114static int __init enforcing_setup(char *str)
115{
116 unsigned long enforcing;
117 if (!kstrtoul(str, 0, &enforcing))
118 selinux_enforcing_boot = enforcing ? 1 : 0;
119 return 1;
120}
121__setup("enforcing=", enforcing_setup);
122#else
123#define selinux_enforcing_boot 1
124#endif
125
126int selinux_enabled_boot __initdata = 1;
127#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
128static int __init selinux_enabled_setup(char *str)
129{
130 unsigned long enabled;
131 if (!kstrtoul(str, 0, &enabled))
132 selinux_enabled_boot = enabled ? 1 : 0;
133 return 1;
134}
135__setup("selinux=", selinux_enabled_setup);
136#endif
137
138static unsigned int selinux_checkreqprot_boot =
139 CONFIG_SECURITY_SELINUX_CHECKREQPROT_VALUE;
140
141static int __init checkreqprot_setup(char *str)
142{
143 unsigned long checkreqprot;
144
145 if (!kstrtoul(str, 0, &checkreqprot)) {
146 selinux_checkreqprot_boot = checkreqprot ? 1 : 0;
147 if (checkreqprot)
148 pr_warn("SELinux: checkreqprot set to 1 via kernel parameter. This is deprecated and will be rejected in a future kernel release.\n");
149 }
150 return 1;
151}
152__setup("checkreqprot=", checkreqprot_setup);
153
154/**
155 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
156 *
157 * Description:
158 * This function checks the SECMARK reference counter to see if any SECMARK
159 * targets are currently configured, if the reference counter is greater than
160 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
161 * enabled, false (0) if SECMARK is disabled. If the always_check_network
162 * policy capability is enabled, SECMARK is always considered enabled.
163 *
164 */
165static int selinux_secmark_enabled(void)
166{
167 return (selinux_policycap_alwaysnetwork() ||
168 atomic_read(&selinux_secmark_refcount));
169}
170
171/**
172 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
173 *
174 * Description:
175 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
176 * (1) if any are enabled or false (0) if neither are enabled. If the
177 * always_check_network policy capability is enabled, peer labeling
178 * is always considered enabled.
179 *
180 */
181static int selinux_peerlbl_enabled(void)
182{
183 return (selinux_policycap_alwaysnetwork() ||
184 netlbl_enabled() || selinux_xfrm_enabled());
185}
186
187static int selinux_netcache_avc_callback(u32 event)
188{
189 if (event == AVC_CALLBACK_RESET) {
190 sel_netif_flush();
191 sel_netnode_flush();
192 sel_netport_flush();
193 synchronize_net();
194 }
195 return 0;
196}
197
198static int selinux_lsm_notifier_avc_callback(u32 event)
199{
200 if (event == AVC_CALLBACK_RESET) {
201 sel_ib_pkey_flush();
202 call_blocking_lsm_notifier(LSM_POLICY_CHANGE, NULL);
203 }
204
205 return 0;
206}
207
208/*
209 * initialise the security for the init task
210 */
211static void cred_init_security(void)
212{
213 struct cred *cred = (struct cred *) current->real_cred;
214 struct task_security_struct *tsec;
215
216 tsec = selinux_cred(cred);
217 tsec->osid = tsec->sid = SECINITSID_KERNEL;
218}
219
220/*
221 * get the security ID of a set of credentials
222 */
223static inline u32 cred_sid(const struct cred *cred)
224{
225 const struct task_security_struct *tsec;
226
227 tsec = selinux_cred(cred);
228 return tsec->sid;
229}
230
231/*
232 * get the objective security ID of a task
233 */
234static inline u32 task_sid(const struct task_struct *task)
235{
236 u32 sid;
237
238 rcu_read_lock();
239 sid = cred_sid(__task_cred(task));
240 rcu_read_unlock();
241 return sid;
242}
243
244static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
245
246/*
247 * Try reloading inode security labels that have been marked as invalid. The
248 * @may_sleep parameter indicates when sleeping and thus reloading labels is
249 * allowed; when set to false, returns -ECHILD when the label is
250 * invalid. The @dentry parameter should be set to a dentry of the inode.
251 */
252static int __inode_security_revalidate(struct inode *inode,
253 struct dentry *dentry,
254 bool may_sleep)
255{
256 struct inode_security_struct *isec = selinux_inode(inode);
257
258 might_sleep_if(may_sleep);
259
260 if (selinux_initialized(&selinux_state) &&
261 isec->initialized != LABEL_INITIALIZED) {
262 if (!may_sleep)
263 return -ECHILD;
264
265 /*
266 * Try reloading the inode security label. This will fail if
267 * @opt_dentry is NULL and no dentry for this inode can be
268 * found; in that case, continue using the old label.
269 */
270 inode_doinit_with_dentry(inode, dentry);
271 }
272 return 0;
273}
274
275static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
276{
277 return selinux_inode(inode);
278}
279
280static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
281{
282 int error;
283
284 error = __inode_security_revalidate(inode, NULL, !rcu);
285 if (error)
286 return ERR_PTR(error);
287 return selinux_inode(inode);
288}
289
290/*
291 * Get the security label of an inode.
292 */
293static struct inode_security_struct *inode_security(struct inode *inode)
294{
295 __inode_security_revalidate(inode, NULL, true);
296 return selinux_inode(inode);
297}
298
299static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
300{
301 struct inode *inode = d_backing_inode(dentry);
302
303 return selinux_inode(inode);
304}
305
306/*
307 * Get the security label of a dentry's backing inode.
308 */
309static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
310{
311 struct inode *inode = d_backing_inode(dentry);
312
313 __inode_security_revalidate(inode, dentry, true);
314 return selinux_inode(inode);
315}
316
317static void inode_free_security(struct inode *inode)
318{
319 struct inode_security_struct *isec = selinux_inode(inode);
320 struct superblock_security_struct *sbsec;
321
322 if (!isec)
323 return;
324 sbsec = inode->i_sb->s_security;
325 /*
326 * As not all inode security structures are in a list, we check for
327 * empty list outside of the lock to make sure that we won't waste
328 * time taking a lock doing nothing.
329 *
330 * The list_del_init() function can be safely called more than once.
331 * It should not be possible for this function to be called with
332 * concurrent list_add(), but for better safety against future changes
333 * in the code, we use list_empty_careful() here.
334 */
335 if (!list_empty_careful(&isec->list)) {
336 spin_lock(&sbsec->isec_lock);
337 list_del_init(&isec->list);
338 spin_unlock(&sbsec->isec_lock);
339 }
340}
341
342static void superblock_free_security(struct super_block *sb)
343{
344 struct superblock_security_struct *sbsec = sb->s_security;
345 sb->s_security = NULL;
346 kfree(sbsec);
347}
348
349struct selinux_mnt_opts {
350 const char *fscontext, *context, *rootcontext, *defcontext;
351};
352
353static void selinux_free_mnt_opts(void *mnt_opts)
354{
355 struct selinux_mnt_opts *opts = mnt_opts;
356 kfree(opts->fscontext);
357 kfree(opts->context);
358 kfree(opts->rootcontext);
359 kfree(opts->defcontext);
360 kfree(opts);
361}
362
363enum {
364 Opt_error = -1,
365 Opt_context = 0,
366 Opt_defcontext = 1,
367 Opt_fscontext = 2,
368 Opt_rootcontext = 3,
369 Opt_seclabel = 4,
370};
371
372#define A(s, has_arg) {#s, sizeof(#s) - 1, Opt_##s, has_arg}
373static struct {
374 const char *name;
375 int len;
376 int opt;
377 bool has_arg;
378} tokens[] = {
379 A(context, true),
380 A(fscontext, true),
381 A(defcontext, true),
382 A(rootcontext, true),
383 A(seclabel, false),
384};
385#undef A
386
387static int match_opt_prefix(char *s, int l, char **arg)
388{
389 int i;
390
391 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
392 size_t len = tokens[i].len;
393 if (len > l || memcmp(s, tokens[i].name, len))
394 continue;
395 if (tokens[i].has_arg) {
396 if (len == l || s[len] != '=')
397 continue;
398 *arg = s + len + 1;
399 } else if (len != l)
400 continue;
401 return tokens[i].opt;
402 }
403 return Opt_error;
404}
405
406#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
407
408static int may_context_mount_sb_relabel(u32 sid,
409 struct superblock_security_struct *sbsec,
410 const struct cred *cred)
411{
412 const struct task_security_struct *tsec = selinux_cred(cred);
413 int rc;
414
415 rc = avc_has_perm(&selinux_state,
416 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
417 FILESYSTEM__RELABELFROM, NULL);
418 if (rc)
419 return rc;
420
421 rc = avc_has_perm(&selinux_state,
422 tsec->sid, sid, SECCLASS_FILESYSTEM,
423 FILESYSTEM__RELABELTO, NULL);
424 return rc;
425}
426
427static int may_context_mount_inode_relabel(u32 sid,
428 struct superblock_security_struct *sbsec,
429 const struct cred *cred)
430{
431 const struct task_security_struct *tsec = selinux_cred(cred);
432 int rc;
433 rc = avc_has_perm(&selinux_state,
434 tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
435 FILESYSTEM__RELABELFROM, NULL);
436 if (rc)
437 return rc;
438
439 rc = avc_has_perm(&selinux_state,
440 sid, sbsec->sid, SECCLASS_FILESYSTEM,
441 FILESYSTEM__ASSOCIATE, NULL);
442 return rc;
443}
444
445static int selinux_is_genfs_special_handling(struct super_block *sb)
446{
447 /* Special handling. Genfs but also in-core setxattr handler */
448 return !strcmp(sb->s_type->name, "sysfs") ||
449 !strcmp(sb->s_type->name, "pstore") ||
450 !strcmp(sb->s_type->name, "debugfs") ||
451 !strcmp(sb->s_type->name, "tracefs") ||
452 !strcmp(sb->s_type->name, "rootfs") ||
453 (selinux_policycap_cgroupseclabel() &&
454 (!strcmp(sb->s_type->name, "cgroup") ||
455 !strcmp(sb->s_type->name, "cgroup2")));
456}
457
458static int selinux_is_sblabel_mnt(struct super_block *sb)
459{
460 struct superblock_security_struct *sbsec = sb->s_security;
461
462 /*
463 * IMPORTANT: Double-check logic in this function when adding a new
464 * SECURITY_FS_USE_* definition!
465 */
466 BUILD_BUG_ON(SECURITY_FS_USE_MAX != 7);
467
468 switch (sbsec->behavior) {
469 case SECURITY_FS_USE_XATTR:
470 case SECURITY_FS_USE_TRANS:
471 case SECURITY_FS_USE_TASK:
472 case SECURITY_FS_USE_NATIVE:
473 return 1;
474
475 case SECURITY_FS_USE_GENFS:
476 return selinux_is_genfs_special_handling(sb);
477
478 /* Never allow relabeling on context mounts */
479 case SECURITY_FS_USE_MNTPOINT:
480 case SECURITY_FS_USE_NONE:
481 default:
482 return 0;
483 }
484}
485
486static int sb_finish_set_opts(struct super_block *sb)
487{
488 struct superblock_security_struct *sbsec = sb->s_security;
489 struct dentry *root = sb->s_root;
490 struct inode *root_inode = d_backing_inode(root);
491 int rc = 0;
492
493 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
494 /* Make sure that the xattr handler exists and that no
495 error other than -ENODATA is returned by getxattr on
496 the root directory. -ENODATA is ok, as this may be
497 the first boot of the SELinux kernel before we have
498 assigned xattr values to the filesystem. */
499 if (!(root_inode->i_opflags & IOP_XATTR)) {
500 pr_warn("SELinux: (dev %s, type %s) has no "
501 "xattr support\n", sb->s_id, sb->s_type->name);
502 rc = -EOPNOTSUPP;
503 goto out;
504 }
505
506 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
507 if (rc < 0 && rc != -ENODATA) {
508 if (rc == -EOPNOTSUPP)
509 pr_warn("SELinux: (dev %s, type "
510 "%s) has no security xattr handler\n",
511 sb->s_id, sb->s_type->name);
512 else
513 pr_warn("SELinux: (dev %s, type "
514 "%s) getxattr errno %d\n", sb->s_id,
515 sb->s_type->name, -rc);
516 goto out;
517 }
518 }
519
520 sbsec->flags |= SE_SBINITIALIZED;
521
522 /*
523 * Explicitly set or clear SBLABEL_MNT. It's not sufficient to simply
524 * leave the flag untouched because sb_clone_mnt_opts might be handing
525 * us a superblock that needs the flag to be cleared.
526 */
527 if (selinux_is_sblabel_mnt(sb))
528 sbsec->flags |= SBLABEL_MNT;
529 else
530 sbsec->flags &= ~SBLABEL_MNT;
531
532 /* Initialize the root inode. */
533 rc = inode_doinit_with_dentry(root_inode, root);
534
535 /* Initialize any other inodes associated with the superblock, e.g.
536 inodes created prior to initial policy load or inodes created
537 during get_sb by a pseudo filesystem that directly
538 populates itself. */
539 spin_lock(&sbsec->isec_lock);
540 while (!list_empty(&sbsec->isec_head)) {
541 struct inode_security_struct *isec =
542 list_first_entry(&sbsec->isec_head,
543 struct inode_security_struct, list);
544 struct inode *inode = isec->inode;
545 list_del_init(&isec->list);
546 spin_unlock(&sbsec->isec_lock);
547 inode = igrab(inode);
548 if (inode) {
549 if (!IS_PRIVATE(inode))
550 inode_doinit_with_dentry(inode, NULL);
551 iput(inode);
552 }
553 spin_lock(&sbsec->isec_lock);
554 }
555 spin_unlock(&sbsec->isec_lock);
556out:
557 return rc;
558}
559
560static int bad_option(struct superblock_security_struct *sbsec, char flag,
561 u32 old_sid, u32 new_sid)
562{
563 char mnt_flags = sbsec->flags & SE_MNTMASK;
564
565 /* check if the old mount command had the same options */
566 if (sbsec->flags & SE_SBINITIALIZED)
567 if (!(sbsec->flags & flag) ||
568 (old_sid != new_sid))
569 return 1;
570
571 /* check if we were passed the same options twice,
572 * aka someone passed context=a,context=b
573 */
574 if (!(sbsec->flags & SE_SBINITIALIZED))
575 if (mnt_flags & flag)
576 return 1;
577 return 0;
578}
579
580static int parse_sid(struct super_block *sb, const char *s, u32 *sid)
581{
582 int rc = security_context_str_to_sid(&selinux_state, s,
583 sid, GFP_KERNEL);
584 if (rc)
585 pr_warn("SELinux: security_context_str_to_sid"
586 "(%s) failed for (dev %s, type %s) errno=%d\n",
587 s, sb->s_id, sb->s_type->name, rc);
588 return rc;
589}
590
591/*
592 * Allow filesystems with binary mount data to explicitly set mount point
593 * labeling information.
594 */
595static int selinux_set_mnt_opts(struct super_block *sb,
596 void *mnt_opts,
597 unsigned long kern_flags,
598 unsigned long *set_kern_flags)
599{
600 const struct cred *cred = current_cred();
601 struct superblock_security_struct *sbsec = sb->s_security;
602 struct dentry *root = sbsec->sb->s_root;
603 struct selinux_mnt_opts *opts = mnt_opts;
604 struct inode_security_struct *root_isec;
605 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
606 u32 defcontext_sid = 0;
607 int rc = 0;
608
609 mutex_lock(&sbsec->lock);
610
611 if (!selinux_initialized(&selinux_state)) {
612 if (!opts) {
613 /* Defer initialization until selinux_complete_init,
614 after the initial policy is loaded and the security
615 server is ready to handle calls. */
616 goto out;
617 }
618 rc = -EINVAL;
619 pr_warn("SELinux: Unable to set superblock options "
620 "before the security server is initialized\n");
621 goto out;
622 }
623 if (kern_flags && !set_kern_flags) {
624 /* Specifying internal flags without providing a place to
625 * place the results is not allowed */
626 rc = -EINVAL;
627 goto out;
628 }
629
630 /*
631 * Binary mount data FS will come through this function twice. Once
632 * from an explicit call and once from the generic calls from the vfs.
633 * Since the generic VFS calls will not contain any security mount data
634 * we need to skip the double mount verification.
635 *
636 * This does open a hole in which we will not notice if the first
637 * mount using this sb set explict options and a second mount using
638 * this sb does not set any security options. (The first options
639 * will be used for both mounts)
640 */
641 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
642 && !opts)
643 goto out;
644
645 root_isec = backing_inode_security_novalidate(root);
646
647 /*
648 * parse the mount options, check if they are valid sids.
649 * also check if someone is trying to mount the same sb more
650 * than once with different security options.
651 */
652 if (opts) {
653 if (opts->fscontext) {
654 rc = parse_sid(sb, opts->fscontext, &fscontext_sid);
655 if (rc)
656 goto out;
657 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
658 fscontext_sid))
659 goto out_double_mount;
660 sbsec->flags |= FSCONTEXT_MNT;
661 }
662 if (opts->context) {
663 rc = parse_sid(sb, opts->context, &context_sid);
664 if (rc)
665 goto out;
666 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
667 context_sid))
668 goto out_double_mount;
669 sbsec->flags |= CONTEXT_MNT;
670 }
671 if (opts->rootcontext) {
672 rc = parse_sid(sb, opts->rootcontext, &rootcontext_sid);
673 if (rc)
674 goto out;
675 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
676 rootcontext_sid))
677 goto out_double_mount;
678 sbsec->flags |= ROOTCONTEXT_MNT;
679 }
680 if (opts->defcontext) {
681 rc = parse_sid(sb, opts->defcontext, &defcontext_sid);
682 if (rc)
683 goto out;
684 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
685 defcontext_sid))
686 goto out_double_mount;
687 sbsec->flags |= DEFCONTEXT_MNT;
688 }
689 }
690
691 if (sbsec->flags & SE_SBINITIALIZED) {
692 /* previously mounted with options, but not on this attempt? */
693 if ((sbsec->flags & SE_MNTMASK) && !opts)
694 goto out_double_mount;
695 rc = 0;
696 goto out;
697 }
698
699 if (strcmp(sb->s_type->name, "proc") == 0)
700 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
701
702 if (!strcmp(sb->s_type->name, "debugfs") ||
703 !strcmp(sb->s_type->name, "tracefs") ||
704 !strcmp(sb->s_type->name, "binder") ||
705 !strcmp(sb->s_type->name, "bpf") ||
706 !strcmp(sb->s_type->name, "pstore"))
707 sbsec->flags |= SE_SBGENFS;
708
709 if (!strcmp(sb->s_type->name, "sysfs") ||
710 !strcmp(sb->s_type->name, "cgroup") ||
711 !strcmp(sb->s_type->name, "cgroup2"))
712 sbsec->flags |= SE_SBGENFS | SE_SBGENFS_XATTR;
713
714 if (!sbsec->behavior) {
715 /*
716 * Determine the labeling behavior to use for this
717 * filesystem type.
718 */
719 rc = security_fs_use(&selinux_state, sb);
720 if (rc) {
721 pr_warn("%s: security_fs_use(%s) returned %d\n",
722 __func__, sb->s_type->name, rc);
723 goto out;
724 }
725 }
726
727 /*
728 * If this is a user namespace mount and the filesystem type is not
729 * explicitly whitelisted, then no contexts are allowed on the command
730 * line and security labels must be ignored.
731 */
732 if (sb->s_user_ns != &init_user_ns &&
733 strcmp(sb->s_type->name, "tmpfs") &&
734 strcmp(sb->s_type->name, "ramfs") &&
735 strcmp(sb->s_type->name, "devpts")) {
736 if (context_sid || fscontext_sid || rootcontext_sid ||
737 defcontext_sid) {
738 rc = -EACCES;
739 goto out;
740 }
741 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
742 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
743 rc = security_transition_sid(&selinux_state,
744 current_sid(),
745 current_sid(),
746 SECCLASS_FILE, NULL,
747 &sbsec->mntpoint_sid);
748 if (rc)
749 goto out;
750 }
751 goto out_set_opts;
752 }
753
754 /* sets the context of the superblock for the fs being mounted. */
755 if (fscontext_sid) {
756 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
757 if (rc)
758 goto out;
759
760 sbsec->sid = fscontext_sid;
761 }
762
763 /*
764 * Switch to using mount point labeling behavior.
765 * sets the label used on all file below the mountpoint, and will set
766 * the superblock context if not already set.
767 */
768 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
769 sbsec->behavior = SECURITY_FS_USE_NATIVE;
770 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
771 }
772
773 if (context_sid) {
774 if (!fscontext_sid) {
775 rc = may_context_mount_sb_relabel(context_sid, sbsec,
776 cred);
777 if (rc)
778 goto out;
779 sbsec->sid = context_sid;
780 } else {
781 rc = may_context_mount_inode_relabel(context_sid, sbsec,
782 cred);
783 if (rc)
784 goto out;
785 }
786 if (!rootcontext_sid)
787 rootcontext_sid = context_sid;
788
789 sbsec->mntpoint_sid = context_sid;
790 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
791 }
792
793 if (rootcontext_sid) {
794 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
795 cred);
796 if (rc)
797 goto out;
798
799 root_isec->sid = rootcontext_sid;
800 root_isec->initialized = LABEL_INITIALIZED;
801 }
802
803 if (defcontext_sid) {
804 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
805 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
806 rc = -EINVAL;
807 pr_warn("SELinux: defcontext option is "
808 "invalid for this filesystem type\n");
809 goto out;
810 }
811
812 if (defcontext_sid != sbsec->def_sid) {
813 rc = may_context_mount_inode_relabel(defcontext_sid,
814 sbsec, cred);
815 if (rc)
816 goto out;
817 }
818
819 sbsec->def_sid = defcontext_sid;
820 }
821
822out_set_opts:
823 rc = sb_finish_set_opts(sb);
824out:
825 mutex_unlock(&sbsec->lock);
826 return rc;
827out_double_mount:
828 rc = -EINVAL;
829 pr_warn("SELinux: mount invalid. Same superblock, different "
830 "security settings for (dev %s, type %s)\n", sb->s_id,
831 sb->s_type->name);
832 goto out;
833}
834
835static int selinux_cmp_sb_context(const struct super_block *oldsb,
836 const struct super_block *newsb)
837{
838 struct superblock_security_struct *old = oldsb->s_security;
839 struct superblock_security_struct *new = newsb->s_security;
840 char oldflags = old->flags & SE_MNTMASK;
841 char newflags = new->flags & SE_MNTMASK;
842
843 if (oldflags != newflags)
844 goto mismatch;
845 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
846 goto mismatch;
847 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
848 goto mismatch;
849 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
850 goto mismatch;
851 if (oldflags & ROOTCONTEXT_MNT) {
852 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
853 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
854 if (oldroot->sid != newroot->sid)
855 goto mismatch;
856 }
857 return 0;
858mismatch:
859 pr_warn("SELinux: mount invalid. Same superblock, "
860 "different security settings for (dev %s, "
861 "type %s)\n", newsb->s_id, newsb->s_type->name);
862 return -EBUSY;
863}
864
865static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
866 struct super_block *newsb,
867 unsigned long kern_flags,
868 unsigned long *set_kern_flags)
869{
870 int rc = 0;
871 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
872 struct superblock_security_struct *newsbsec = newsb->s_security;
873
874 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
875 int set_context = (oldsbsec->flags & CONTEXT_MNT);
876 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
877
878 /*
879 * if the parent was able to be mounted it clearly had no special lsm
880 * mount options. thus we can safely deal with this superblock later
881 */
882 if (!selinux_initialized(&selinux_state))
883 return 0;
884
885 /*
886 * Specifying internal flags without providing a place to
887 * place the results is not allowed.
888 */
889 if (kern_flags && !set_kern_flags)
890 return -EINVAL;
891
892 /* how can we clone if the old one wasn't set up?? */
893 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
894
895 /* if fs is reusing a sb, make sure that the contexts match */
896 if (newsbsec->flags & SE_SBINITIALIZED) {
897 if ((kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context)
898 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
899 return selinux_cmp_sb_context(oldsb, newsb);
900 }
901
902 mutex_lock(&newsbsec->lock);
903
904 newsbsec->flags = oldsbsec->flags;
905
906 newsbsec->sid = oldsbsec->sid;
907 newsbsec->def_sid = oldsbsec->def_sid;
908 newsbsec->behavior = oldsbsec->behavior;
909
910 if (newsbsec->behavior == SECURITY_FS_USE_NATIVE &&
911 !(kern_flags & SECURITY_LSM_NATIVE_LABELS) && !set_context) {
912 rc = security_fs_use(&selinux_state, newsb);
913 if (rc)
914 goto out;
915 }
916
917 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !set_context) {
918 newsbsec->behavior = SECURITY_FS_USE_NATIVE;
919 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
920 }
921
922 if (set_context) {
923 u32 sid = oldsbsec->mntpoint_sid;
924
925 if (!set_fscontext)
926 newsbsec->sid = sid;
927 if (!set_rootcontext) {
928 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
929 newisec->sid = sid;
930 }
931 newsbsec->mntpoint_sid = sid;
932 }
933 if (set_rootcontext) {
934 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
935 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
936
937 newisec->sid = oldisec->sid;
938 }
939
940 sb_finish_set_opts(newsb);
941out:
942 mutex_unlock(&newsbsec->lock);
943 return rc;
944}
945
946static int selinux_add_opt(int token, const char *s, void **mnt_opts)
947{
948 struct selinux_mnt_opts *opts = *mnt_opts;
949
950 if (token == Opt_seclabel) /* eaten and completely ignored */
951 return 0;
952
953 if (!opts) {
954 opts = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
955 if (!opts)
956 return -ENOMEM;
957 *mnt_opts = opts;
958 }
959 if (!s)
960 return -ENOMEM;
961 switch (token) {
962 case Opt_context:
963 if (opts->context || opts->defcontext)
964 goto Einval;
965 opts->context = s;
966 break;
967 case Opt_fscontext:
968 if (opts->fscontext)
969 goto Einval;
970 opts->fscontext = s;
971 break;
972 case Opt_rootcontext:
973 if (opts->rootcontext)
974 goto Einval;
975 opts->rootcontext = s;
976 break;
977 case Opt_defcontext:
978 if (opts->context || opts->defcontext)
979 goto Einval;
980 opts->defcontext = s;
981 break;
982 }
983 return 0;
984Einval:
985 pr_warn(SEL_MOUNT_FAIL_MSG);
986 return -EINVAL;
987}
988
989static int selinux_add_mnt_opt(const char *option, const char *val, int len,
990 void **mnt_opts)
991{
992 int token = Opt_error;
993 int rc, i;
994
995 for (i = 0; i < ARRAY_SIZE(tokens); i++) {
996 if (strcmp(option, tokens[i].name) == 0) {
997 token = tokens[i].opt;
998 break;
999 }
1000 }
1001
1002 if (token == Opt_error)
1003 return -EINVAL;
1004
1005 if (token != Opt_seclabel) {
1006 val = kmemdup_nul(val, len, GFP_KERNEL);
1007 if (!val) {
1008 rc = -ENOMEM;
1009 goto free_opt;
1010 }
1011 }
1012 rc = selinux_add_opt(token, val, mnt_opts);
1013 if (unlikely(rc)) {
1014 kfree(val);
1015 goto free_opt;
1016 }
1017 return rc;
1018
1019free_opt:
1020 if (*mnt_opts) {
1021 selinux_free_mnt_opts(*mnt_opts);
1022 *mnt_opts = NULL;
1023 }
1024 return rc;
1025}
1026
1027static int show_sid(struct seq_file *m, u32 sid)
1028{
1029 char *context = NULL;
1030 u32 len;
1031 int rc;
1032
1033 rc = security_sid_to_context(&selinux_state, sid,
1034 &context, &len);
1035 if (!rc) {
1036 bool has_comma = context && strchr(context, ',');
1037
1038 seq_putc(m, '=');
1039 if (has_comma)
1040 seq_putc(m, '\"');
1041 seq_escape(m, context, "\"\n\\");
1042 if (has_comma)
1043 seq_putc(m, '\"');
1044 }
1045 kfree(context);
1046 return rc;
1047}
1048
1049static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1050{
1051 struct superblock_security_struct *sbsec = sb->s_security;
1052 int rc;
1053
1054 if (!(sbsec->flags & SE_SBINITIALIZED))
1055 return 0;
1056
1057 if (!selinux_initialized(&selinux_state))
1058 return 0;
1059
1060 if (sbsec->flags & FSCONTEXT_MNT) {
1061 seq_putc(m, ',');
1062 seq_puts(m, FSCONTEXT_STR);
1063 rc = show_sid(m, sbsec->sid);
1064 if (rc)
1065 return rc;
1066 }
1067 if (sbsec->flags & CONTEXT_MNT) {
1068 seq_putc(m, ',');
1069 seq_puts(m, CONTEXT_STR);
1070 rc = show_sid(m, sbsec->mntpoint_sid);
1071 if (rc)
1072 return rc;
1073 }
1074 if (sbsec->flags & DEFCONTEXT_MNT) {
1075 seq_putc(m, ',');
1076 seq_puts(m, DEFCONTEXT_STR);
1077 rc = show_sid(m, sbsec->def_sid);
1078 if (rc)
1079 return rc;
1080 }
1081 if (sbsec->flags & ROOTCONTEXT_MNT) {
1082 struct dentry *root = sbsec->sb->s_root;
1083 struct inode_security_struct *isec = backing_inode_security(root);
1084 seq_putc(m, ',');
1085 seq_puts(m, ROOTCONTEXT_STR);
1086 rc = show_sid(m, isec->sid);
1087 if (rc)
1088 return rc;
1089 }
1090 if (sbsec->flags & SBLABEL_MNT) {
1091 seq_putc(m, ',');
1092 seq_puts(m, SECLABEL_STR);
1093 }
1094 return 0;
1095}
1096
1097static inline u16 inode_mode_to_security_class(umode_t mode)
1098{
1099 switch (mode & S_IFMT) {
1100 case S_IFSOCK:
1101 return SECCLASS_SOCK_FILE;
1102 case S_IFLNK:
1103 return SECCLASS_LNK_FILE;
1104 case S_IFREG:
1105 return SECCLASS_FILE;
1106 case S_IFBLK:
1107 return SECCLASS_BLK_FILE;
1108 case S_IFDIR:
1109 return SECCLASS_DIR;
1110 case S_IFCHR:
1111 return SECCLASS_CHR_FILE;
1112 case S_IFIFO:
1113 return SECCLASS_FIFO_FILE;
1114
1115 }
1116
1117 return SECCLASS_FILE;
1118}
1119
1120static inline int default_protocol_stream(int protocol)
1121{
1122 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1123}
1124
1125static inline int default_protocol_dgram(int protocol)
1126{
1127 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1128}
1129
1130static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1131{
1132 int extsockclass = selinux_policycap_extsockclass();
1133
1134 switch (family) {
1135 case PF_UNIX:
1136 switch (type) {
1137 case SOCK_STREAM:
1138 case SOCK_SEQPACKET:
1139 return SECCLASS_UNIX_STREAM_SOCKET;
1140 case SOCK_DGRAM:
1141 case SOCK_RAW:
1142 return SECCLASS_UNIX_DGRAM_SOCKET;
1143 }
1144 break;
1145 case PF_INET:
1146 case PF_INET6:
1147 switch (type) {
1148 case SOCK_STREAM:
1149 case SOCK_SEQPACKET:
1150 if (default_protocol_stream(protocol))
1151 return SECCLASS_TCP_SOCKET;
1152 else if (extsockclass && protocol == IPPROTO_SCTP)
1153 return SECCLASS_SCTP_SOCKET;
1154 else
1155 return SECCLASS_RAWIP_SOCKET;
1156 case SOCK_DGRAM:
1157 if (default_protocol_dgram(protocol))
1158 return SECCLASS_UDP_SOCKET;
1159 else if (extsockclass && (protocol == IPPROTO_ICMP ||
1160 protocol == IPPROTO_ICMPV6))
1161 return SECCLASS_ICMP_SOCKET;
1162 else
1163 return SECCLASS_RAWIP_SOCKET;
1164 case SOCK_DCCP:
1165 return SECCLASS_DCCP_SOCKET;
1166 default:
1167 return SECCLASS_RAWIP_SOCKET;
1168 }
1169 break;
1170 case PF_NETLINK:
1171 switch (protocol) {
1172 case NETLINK_ROUTE:
1173 return SECCLASS_NETLINK_ROUTE_SOCKET;
1174 case NETLINK_SOCK_DIAG:
1175 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1176 case NETLINK_NFLOG:
1177 return SECCLASS_NETLINK_NFLOG_SOCKET;
1178 case NETLINK_XFRM:
1179 return SECCLASS_NETLINK_XFRM_SOCKET;
1180 case NETLINK_SELINUX:
1181 return SECCLASS_NETLINK_SELINUX_SOCKET;
1182 case NETLINK_ISCSI:
1183 return SECCLASS_NETLINK_ISCSI_SOCKET;
1184 case NETLINK_AUDIT:
1185 return SECCLASS_NETLINK_AUDIT_SOCKET;
1186 case NETLINK_FIB_LOOKUP:
1187 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1188 case NETLINK_CONNECTOR:
1189 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1190 case NETLINK_NETFILTER:
1191 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1192 case NETLINK_DNRTMSG:
1193 return SECCLASS_NETLINK_DNRT_SOCKET;
1194 case NETLINK_KOBJECT_UEVENT:
1195 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1196 case NETLINK_GENERIC:
1197 return SECCLASS_NETLINK_GENERIC_SOCKET;
1198 case NETLINK_SCSITRANSPORT:
1199 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1200 case NETLINK_RDMA:
1201 return SECCLASS_NETLINK_RDMA_SOCKET;
1202 case NETLINK_CRYPTO:
1203 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1204 default:
1205 return SECCLASS_NETLINK_SOCKET;
1206 }
1207 case PF_PACKET:
1208 return SECCLASS_PACKET_SOCKET;
1209 case PF_KEY:
1210 return SECCLASS_KEY_SOCKET;
1211 case PF_APPLETALK:
1212 return SECCLASS_APPLETALK_SOCKET;
1213 }
1214
1215 if (extsockclass) {
1216 switch (family) {
1217 case PF_AX25:
1218 return SECCLASS_AX25_SOCKET;
1219 case PF_IPX:
1220 return SECCLASS_IPX_SOCKET;
1221 case PF_NETROM:
1222 return SECCLASS_NETROM_SOCKET;
1223 case PF_ATMPVC:
1224 return SECCLASS_ATMPVC_SOCKET;
1225 case PF_X25:
1226 return SECCLASS_X25_SOCKET;
1227 case PF_ROSE:
1228 return SECCLASS_ROSE_SOCKET;
1229 case PF_DECnet:
1230 return SECCLASS_DECNET_SOCKET;
1231 case PF_ATMSVC:
1232 return SECCLASS_ATMSVC_SOCKET;
1233 case PF_RDS:
1234 return SECCLASS_RDS_SOCKET;
1235 case PF_IRDA:
1236 return SECCLASS_IRDA_SOCKET;
1237 case PF_PPPOX:
1238 return SECCLASS_PPPOX_SOCKET;
1239 case PF_LLC:
1240 return SECCLASS_LLC_SOCKET;
1241 case PF_CAN:
1242 return SECCLASS_CAN_SOCKET;
1243 case PF_TIPC:
1244 return SECCLASS_TIPC_SOCKET;
1245 case PF_BLUETOOTH:
1246 return SECCLASS_BLUETOOTH_SOCKET;
1247 case PF_IUCV:
1248 return SECCLASS_IUCV_SOCKET;
1249 case PF_RXRPC:
1250 return SECCLASS_RXRPC_SOCKET;
1251 case PF_ISDN:
1252 return SECCLASS_ISDN_SOCKET;
1253 case PF_PHONET:
1254 return SECCLASS_PHONET_SOCKET;
1255 case PF_IEEE802154:
1256 return SECCLASS_IEEE802154_SOCKET;
1257 case PF_CAIF:
1258 return SECCLASS_CAIF_SOCKET;
1259 case PF_ALG:
1260 return SECCLASS_ALG_SOCKET;
1261 case PF_NFC:
1262 return SECCLASS_NFC_SOCKET;
1263 case PF_VSOCK:
1264 return SECCLASS_VSOCK_SOCKET;
1265 case PF_KCM:
1266 return SECCLASS_KCM_SOCKET;
1267 case PF_QIPCRTR:
1268 return SECCLASS_QIPCRTR_SOCKET;
1269 case PF_SMC:
1270 return SECCLASS_SMC_SOCKET;
1271 case PF_XDP:
1272 return SECCLASS_XDP_SOCKET;
1273#if PF_MAX > 45
1274#error New address family defined, please update this function.
1275#endif
1276 }
1277 }
1278
1279 return SECCLASS_SOCKET;
1280}
1281
1282static int selinux_genfs_get_sid(struct dentry *dentry,
1283 u16 tclass,
1284 u16 flags,
1285 u32 *sid)
1286{
1287 int rc;
1288 struct super_block *sb = dentry->d_sb;
1289 char *buffer, *path;
1290
1291 buffer = (char *)__get_free_page(GFP_KERNEL);
1292 if (!buffer)
1293 return -ENOMEM;
1294
1295 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1296 if (IS_ERR(path))
1297 rc = PTR_ERR(path);
1298 else {
1299 if (flags & SE_SBPROC) {
1300 /* each process gets a /proc/PID/ entry. Strip off the
1301 * PID part to get a valid selinux labeling.
1302 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1303 while (path[1] >= '0' && path[1] <= '9') {
1304 path[1] = '/';
1305 path++;
1306 }
1307 }
1308 rc = security_genfs_sid(&selinux_state, sb->s_type->name,
1309 path, tclass, sid);
1310 if (rc == -ENOENT) {
1311 /* No match in policy, mark as unlabeled. */
1312 *sid = SECINITSID_UNLABELED;
1313 rc = 0;
1314 }
1315 }
1316 free_page((unsigned long)buffer);
1317 return rc;
1318}
1319
1320static int inode_doinit_use_xattr(struct inode *inode, struct dentry *dentry,
1321 u32 def_sid, u32 *sid)
1322{
1323#define INITCONTEXTLEN 255
1324 char *context;
1325 unsigned int len;
1326 int rc;
1327
1328 len = INITCONTEXTLEN;
1329 context = kmalloc(len + 1, GFP_NOFS);
1330 if (!context)
1331 return -ENOMEM;
1332
1333 context[len] = '\0';
1334 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1335 if (rc == -ERANGE) {
1336 kfree(context);
1337
1338 /* Need a larger buffer. Query for the right size. */
1339 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1340 if (rc < 0)
1341 return rc;
1342
1343 len = rc;
1344 context = kmalloc(len + 1, GFP_NOFS);
1345 if (!context)
1346 return -ENOMEM;
1347
1348 context[len] = '\0';
1349 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX,
1350 context, len);
1351 }
1352 if (rc < 0) {
1353 kfree(context);
1354 if (rc != -ENODATA) {
1355 pr_warn("SELinux: %s: getxattr returned %d for dev=%s ino=%ld\n",
1356 __func__, -rc, inode->i_sb->s_id, inode->i_ino);
1357 return rc;
1358 }
1359 *sid = def_sid;
1360 return 0;
1361 }
1362
1363 rc = security_context_to_sid_default(&selinux_state, context, rc, sid,
1364 def_sid, GFP_NOFS);
1365 if (rc) {
1366 char *dev = inode->i_sb->s_id;
1367 unsigned long ino = inode->i_ino;
1368
1369 if (rc == -EINVAL) {
1370 pr_notice_ratelimited("SELinux: inode=%lu on dev=%s was found to have an invalid context=%s. This indicates you may need to relabel the inode or the filesystem in question.\n",
1371 ino, dev, context);
1372 } else {
1373 pr_warn("SELinux: %s: context_to_sid(%s) returned %d for dev=%s ino=%ld\n",
1374 __func__, context, -rc, dev, ino);
1375 }
1376 }
1377 kfree(context);
1378 return 0;
1379}
1380
1381/* The inode's security attributes must be initialized before first use. */
1382static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1383{
1384 struct superblock_security_struct *sbsec = NULL;
1385 struct inode_security_struct *isec = selinux_inode(inode);
1386 u32 task_sid, sid = 0;
1387 u16 sclass;
1388 struct dentry *dentry;
1389 int rc = 0;
1390
1391 if (isec->initialized == LABEL_INITIALIZED)
1392 return 0;
1393
1394 spin_lock(&isec->lock);
1395 if (isec->initialized == LABEL_INITIALIZED)
1396 goto out_unlock;
1397
1398 if (isec->sclass == SECCLASS_FILE)
1399 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1400
1401 sbsec = inode->i_sb->s_security;
1402 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1403 /* Defer initialization until selinux_complete_init,
1404 after the initial policy is loaded and the security
1405 server is ready to handle calls. */
1406 spin_lock(&sbsec->isec_lock);
1407 if (list_empty(&isec->list))
1408 list_add(&isec->list, &sbsec->isec_head);
1409 spin_unlock(&sbsec->isec_lock);
1410 goto out_unlock;
1411 }
1412
1413 sclass = isec->sclass;
1414 task_sid = isec->task_sid;
1415 sid = isec->sid;
1416 isec->initialized = LABEL_PENDING;
1417 spin_unlock(&isec->lock);
1418
1419 switch (sbsec->behavior) {
1420 case SECURITY_FS_USE_NATIVE:
1421 break;
1422 case SECURITY_FS_USE_XATTR:
1423 if (!(inode->i_opflags & IOP_XATTR)) {
1424 sid = sbsec->def_sid;
1425 break;
1426 }
1427 /* Need a dentry, since the xattr API requires one.
1428 Life would be simpler if we could just pass the inode. */
1429 if (opt_dentry) {
1430 /* Called from d_instantiate or d_splice_alias. */
1431 dentry = dget(opt_dentry);
1432 } else {
1433 /*
1434 * Called from selinux_complete_init, try to find a dentry.
1435 * Some filesystems really want a connected one, so try
1436 * that first. We could split SECURITY_FS_USE_XATTR in
1437 * two, depending upon that...
1438 */
1439 dentry = d_find_alias(inode);
1440 if (!dentry)
1441 dentry = d_find_any_alias(inode);
1442 }
1443 if (!dentry) {
1444 /*
1445 * this is can be hit on boot when a file is accessed
1446 * before the policy is loaded. When we load policy we
1447 * may find inodes that have no dentry on the
1448 * sbsec->isec_head list. No reason to complain as these
1449 * will get fixed up the next time we go through
1450 * inode_doinit with a dentry, before these inodes could
1451 * be used again by userspace.
1452 */
1453 goto out;
1454 }
1455
1456 rc = inode_doinit_use_xattr(inode, dentry, sbsec->def_sid,
1457 &sid);
1458 dput(dentry);
1459 if (rc)
1460 goto out;
1461 break;
1462 case SECURITY_FS_USE_TASK:
1463 sid = task_sid;
1464 break;
1465 case SECURITY_FS_USE_TRANS:
1466 /* Default to the fs SID. */
1467 sid = sbsec->sid;
1468
1469 /* Try to obtain a transition SID. */
1470 rc = security_transition_sid(&selinux_state, task_sid, sid,
1471 sclass, NULL, &sid);
1472 if (rc)
1473 goto out;
1474 break;
1475 case SECURITY_FS_USE_MNTPOINT:
1476 sid = sbsec->mntpoint_sid;
1477 break;
1478 default:
1479 /* Default to the fs superblock SID. */
1480 sid = sbsec->sid;
1481
1482 if ((sbsec->flags & SE_SBGENFS) &&
1483 (!S_ISLNK(inode->i_mode) ||
1484 selinux_policycap_genfs_seclabel_symlinks())) {
1485 /* We must have a dentry to determine the label on
1486 * procfs inodes */
1487 if (opt_dentry) {
1488 /* Called from d_instantiate or
1489 * d_splice_alias. */
1490 dentry = dget(opt_dentry);
1491 } else {
1492 /* Called from selinux_complete_init, try to
1493 * find a dentry. Some filesystems really want
1494 * a connected one, so try that first.
1495 */
1496 dentry = d_find_alias(inode);
1497 if (!dentry)
1498 dentry = d_find_any_alias(inode);
1499 }
1500 /*
1501 * This can be hit on boot when a file is accessed
1502 * before the policy is loaded. When we load policy we
1503 * may find inodes that have no dentry on the
1504 * sbsec->isec_head list. No reason to complain as
1505 * these will get fixed up the next time we go through
1506 * inode_doinit() with a dentry, before these inodes
1507 * could be used again by userspace.
1508 */
1509 if (!dentry)
1510 goto out;
1511 rc = selinux_genfs_get_sid(dentry, sclass,
1512 sbsec->flags, &sid);
1513 if (rc) {
1514 dput(dentry);
1515 goto out;
1516 }
1517
1518 if ((sbsec->flags & SE_SBGENFS_XATTR) &&
1519 (inode->i_opflags & IOP_XATTR)) {
1520 rc = inode_doinit_use_xattr(inode, dentry,
1521 sid, &sid);
1522 if (rc) {
1523 dput(dentry);
1524 goto out;
1525 }
1526 }
1527 dput(dentry);
1528 }
1529 break;
1530 }
1531
1532out:
1533 spin_lock(&isec->lock);
1534 if (isec->initialized == LABEL_PENDING) {
1535 if (!sid || rc) {
1536 isec->initialized = LABEL_INVALID;
1537 goto out_unlock;
1538 }
1539
1540 isec->initialized = LABEL_INITIALIZED;
1541 isec->sid = sid;
1542 }
1543
1544out_unlock:
1545 spin_unlock(&isec->lock);
1546 return rc;
1547}
1548
1549/* Convert a Linux signal to an access vector. */
1550static inline u32 signal_to_av(int sig)
1551{
1552 u32 perm = 0;
1553
1554 switch (sig) {
1555 case SIGCHLD:
1556 /* Commonly granted from child to parent. */
1557 perm = PROCESS__SIGCHLD;
1558 break;
1559 case SIGKILL:
1560 /* Cannot be caught or ignored */
1561 perm = PROCESS__SIGKILL;
1562 break;
1563 case SIGSTOP:
1564 /* Cannot be caught or ignored */
1565 perm = PROCESS__SIGSTOP;
1566 break;
1567 default:
1568 /* All other signals. */
1569 perm = PROCESS__SIGNAL;
1570 break;
1571 }
1572
1573 return perm;
1574}
1575
1576#if CAP_LAST_CAP > 63
1577#error Fix SELinux to handle capabilities > 63.
1578#endif
1579
1580/* Check whether a task is allowed to use a capability. */
1581static int cred_has_capability(const struct cred *cred,
1582 int cap, unsigned int opts, bool initns)
1583{
1584 struct common_audit_data ad;
1585 struct av_decision avd;
1586 u16 sclass;
1587 u32 sid = cred_sid(cred);
1588 u32 av = CAP_TO_MASK(cap);
1589 int rc;
1590
1591 ad.type = LSM_AUDIT_DATA_CAP;
1592 ad.u.cap = cap;
1593
1594 switch (CAP_TO_INDEX(cap)) {
1595 case 0:
1596 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1597 break;
1598 case 1:
1599 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1600 break;
1601 default:
1602 pr_err("SELinux: out of range capability %d\n", cap);
1603 BUG();
1604 return -EINVAL;
1605 }
1606
1607 rc = avc_has_perm_noaudit(&selinux_state,
1608 sid, sid, sclass, av, 0, &avd);
1609 if (!(opts & CAP_OPT_NOAUDIT)) {
1610 int rc2 = avc_audit(&selinux_state,
1611 sid, sid, sclass, av, &avd, rc, &ad, 0);
1612 if (rc2)
1613 return rc2;
1614 }
1615 return rc;
1616}
1617
1618/* Check whether a task has a particular permission to an inode.
1619 The 'adp' parameter is optional and allows other audit
1620 data to be passed (e.g. the dentry). */
1621static int inode_has_perm(const struct cred *cred,
1622 struct inode *inode,
1623 u32 perms,
1624 struct common_audit_data *adp)
1625{
1626 struct inode_security_struct *isec;
1627 u32 sid;
1628
1629 validate_creds(cred);
1630
1631 if (unlikely(IS_PRIVATE(inode)))
1632 return 0;
1633
1634 sid = cred_sid(cred);
1635 isec = selinux_inode(inode);
1636
1637 return avc_has_perm(&selinux_state,
1638 sid, isec->sid, isec->sclass, perms, adp);
1639}
1640
1641/* Same as inode_has_perm, but pass explicit audit data containing
1642 the dentry to help the auditing code to more easily generate the
1643 pathname if needed. */
1644static inline int dentry_has_perm(const struct cred *cred,
1645 struct dentry *dentry,
1646 u32 av)
1647{
1648 struct inode *inode = d_backing_inode(dentry);
1649 struct common_audit_data ad;
1650
1651 ad.type = LSM_AUDIT_DATA_DENTRY;
1652 ad.u.dentry = dentry;
1653 __inode_security_revalidate(inode, dentry, true);
1654 return inode_has_perm(cred, inode, av, &ad);
1655}
1656
1657/* Same as inode_has_perm, but pass explicit audit data containing
1658 the path to help the auditing code to more easily generate the
1659 pathname if needed. */
1660static inline int path_has_perm(const struct cred *cred,
1661 const struct path *path,
1662 u32 av)
1663{
1664 struct inode *inode = d_backing_inode(path->dentry);
1665 struct common_audit_data ad;
1666
1667 ad.type = LSM_AUDIT_DATA_PATH;
1668 ad.u.path = *path;
1669 __inode_security_revalidate(inode, path->dentry, true);
1670 return inode_has_perm(cred, inode, av, &ad);
1671}
1672
1673/* Same as path_has_perm, but uses the inode from the file struct. */
1674static inline int file_path_has_perm(const struct cred *cred,
1675 struct file *file,
1676 u32 av)
1677{
1678 struct common_audit_data ad;
1679
1680 ad.type = LSM_AUDIT_DATA_FILE;
1681 ad.u.file = file;
1682 return inode_has_perm(cred, file_inode(file), av, &ad);
1683}
1684
1685#ifdef CONFIG_BPF_SYSCALL
1686static int bpf_fd_pass(struct file *file, u32 sid);
1687#endif
1688
1689/* Check whether a task can use an open file descriptor to
1690 access an inode in a given way. Check access to the
1691 descriptor itself, and then use dentry_has_perm to
1692 check a particular permission to the file.
1693 Access to the descriptor is implicitly granted if it
1694 has the same SID as the process. If av is zero, then
1695 access to the file is not checked, e.g. for cases
1696 where only the descriptor is affected like seek. */
1697static int file_has_perm(const struct cred *cred,
1698 struct file *file,
1699 u32 av)
1700{
1701 struct file_security_struct *fsec = selinux_file(file);
1702 struct inode *inode = file_inode(file);
1703 struct common_audit_data ad;
1704 u32 sid = cred_sid(cred);
1705 int rc;
1706
1707 ad.type = LSM_AUDIT_DATA_FILE;
1708 ad.u.file = file;
1709
1710 if (sid != fsec->sid) {
1711 rc = avc_has_perm(&selinux_state,
1712 sid, fsec->sid,
1713 SECCLASS_FD,
1714 FD__USE,
1715 &ad);
1716 if (rc)
1717 goto out;
1718 }
1719
1720#ifdef CONFIG_BPF_SYSCALL
1721 rc = bpf_fd_pass(file, cred_sid(cred));
1722 if (rc)
1723 return rc;
1724#endif
1725
1726 /* av is zero if only checking access to the descriptor. */
1727 rc = 0;
1728 if (av)
1729 rc = inode_has_perm(cred, inode, av, &ad);
1730
1731out:
1732 return rc;
1733}
1734
1735/*
1736 * Determine the label for an inode that might be unioned.
1737 */
1738static int
1739selinux_determine_inode_label(const struct task_security_struct *tsec,
1740 struct inode *dir,
1741 const struct qstr *name, u16 tclass,
1742 u32 *_new_isid)
1743{
1744 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1745
1746 if ((sbsec->flags & SE_SBINITIALIZED) &&
1747 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1748 *_new_isid = sbsec->mntpoint_sid;
1749 } else if ((sbsec->flags & SBLABEL_MNT) &&
1750 tsec->create_sid) {
1751 *_new_isid = tsec->create_sid;
1752 } else {
1753 const struct inode_security_struct *dsec = inode_security(dir);
1754 return security_transition_sid(&selinux_state, tsec->sid,
1755 dsec->sid, tclass,
1756 name, _new_isid);
1757 }
1758
1759 return 0;
1760}
1761
1762/* Check whether a task can create a file. */
1763static int may_create(struct inode *dir,
1764 struct dentry *dentry,
1765 u16 tclass)
1766{
1767 const struct task_security_struct *tsec = selinux_cred(current_cred());
1768 struct inode_security_struct *dsec;
1769 struct superblock_security_struct *sbsec;
1770 u32 sid, newsid;
1771 struct common_audit_data ad;
1772 int rc;
1773
1774 dsec = inode_security(dir);
1775 sbsec = dir->i_sb->s_security;
1776
1777 sid = tsec->sid;
1778
1779 ad.type = LSM_AUDIT_DATA_DENTRY;
1780 ad.u.dentry = dentry;
1781
1782 rc = avc_has_perm(&selinux_state,
1783 sid, dsec->sid, SECCLASS_DIR,
1784 DIR__ADD_NAME | DIR__SEARCH,
1785 &ad);
1786 if (rc)
1787 return rc;
1788
1789 rc = selinux_determine_inode_label(tsec, dir, &dentry->d_name, tclass,
1790 &newsid);
1791 if (rc)
1792 return rc;
1793
1794 rc = avc_has_perm(&selinux_state,
1795 sid, newsid, tclass, FILE__CREATE, &ad);
1796 if (rc)
1797 return rc;
1798
1799 return avc_has_perm(&selinux_state,
1800 newsid, sbsec->sid,
1801 SECCLASS_FILESYSTEM,
1802 FILESYSTEM__ASSOCIATE, &ad);
1803}
1804
1805#define MAY_LINK 0
1806#define MAY_UNLINK 1
1807#define MAY_RMDIR 2
1808
1809/* Check whether a task can link, unlink, or rmdir a file/directory. */
1810static int may_link(struct inode *dir,
1811 struct dentry *dentry,
1812 int kind)
1813
1814{
1815 struct inode_security_struct *dsec, *isec;
1816 struct common_audit_data ad;
1817 u32 sid = current_sid();
1818 u32 av;
1819 int rc;
1820
1821 dsec = inode_security(dir);
1822 isec = backing_inode_security(dentry);
1823
1824 ad.type = LSM_AUDIT_DATA_DENTRY;
1825 ad.u.dentry = dentry;
1826
1827 av = DIR__SEARCH;
1828 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1829 rc = avc_has_perm(&selinux_state,
1830 sid, dsec->sid, SECCLASS_DIR, av, &ad);
1831 if (rc)
1832 return rc;
1833
1834 switch (kind) {
1835 case MAY_LINK:
1836 av = FILE__LINK;
1837 break;
1838 case MAY_UNLINK:
1839 av = FILE__UNLINK;
1840 break;
1841 case MAY_RMDIR:
1842 av = DIR__RMDIR;
1843 break;
1844 default:
1845 pr_warn("SELinux: %s: unrecognized kind %d\n",
1846 __func__, kind);
1847 return 0;
1848 }
1849
1850 rc = avc_has_perm(&selinux_state,
1851 sid, isec->sid, isec->sclass, av, &ad);
1852 return rc;
1853}
1854
1855static inline int may_rename(struct inode *old_dir,
1856 struct dentry *old_dentry,
1857 struct inode *new_dir,
1858 struct dentry *new_dentry)
1859{
1860 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1861 struct common_audit_data ad;
1862 u32 sid = current_sid();
1863 u32 av;
1864 int old_is_dir, new_is_dir;
1865 int rc;
1866
1867 old_dsec = inode_security(old_dir);
1868 old_isec = backing_inode_security(old_dentry);
1869 old_is_dir = d_is_dir(old_dentry);
1870 new_dsec = inode_security(new_dir);
1871
1872 ad.type = LSM_AUDIT_DATA_DENTRY;
1873
1874 ad.u.dentry = old_dentry;
1875 rc = avc_has_perm(&selinux_state,
1876 sid, old_dsec->sid, SECCLASS_DIR,
1877 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1878 if (rc)
1879 return rc;
1880 rc = avc_has_perm(&selinux_state,
1881 sid, old_isec->sid,
1882 old_isec->sclass, FILE__RENAME, &ad);
1883 if (rc)
1884 return rc;
1885 if (old_is_dir && new_dir != old_dir) {
1886 rc = avc_has_perm(&selinux_state,
1887 sid, old_isec->sid,
1888 old_isec->sclass, DIR__REPARENT, &ad);
1889 if (rc)
1890 return rc;
1891 }
1892
1893 ad.u.dentry = new_dentry;
1894 av = DIR__ADD_NAME | DIR__SEARCH;
1895 if (d_is_positive(new_dentry))
1896 av |= DIR__REMOVE_NAME;
1897 rc = avc_has_perm(&selinux_state,
1898 sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1899 if (rc)
1900 return rc;
1901 if (d_is_positive(new_dentry)) {
1902 new_isec = backing_inode_security(new_dentry);
1903 new_is_dir = d_is_dir(new_dentry);
1904 rc = avc_has_perm(&selinux_state,
1905 sid, new_isec->sid,
1906 new_isec->sclass,
1907 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1908 if (rc)
1909 return rc;
1910 }
1911
1912 return 0;
1913}
1914
1915/* Check whether a task can perform a filesystem operation. */
1916static int superblock_has_perm(const struct cred *cred,
1917 struct super_block *sb,
1918 u32 perms,
1919 struct common_audit_data *ad)
1920{
1921 struct superblock_security_struct *sbsec;
1922 u32 sid = cred_sid(cred);
1923
1924 sbsec = sb->s_security;
1925 return avc_has_perm(&selinux_state,
1926 sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1927}
1928
1929/* Convert a Linux mode and permission mask to an access vector. */
1930static inline u32 file_mask_to_av(int mode, int mask)
1931{
1932 u32 av = 0;
1933
1934 if (!S_ISDIR(mode)) {
1935 if (mask & MAY_EXEC)
1936 av |= FILE__EXECUTE;
1937 if (mask & MAY_READ)
1938 av |= FILE__READ;
1939
1940 if (mask & MAY_APPEND)
1941 av |= FILE__APPEND;
1942 else if (mask & MAY_WRITE)
1943 av |= FILE__WRITE;
1944
1945 } else {
1946 if (mask & MAY_EXEC)
1947 av |= DIR__SEARCH;
1948 if (mask & MAY_WRITE)
1949 av |= DIR__WRITE;
1950 if (mask & MAY_READ)
1951 av |= DIR__READ;
1952 }
1953
1954 return av;
1955}
1956
1957/* Convert a Linux file to an access vector. */
1958static inline u32 file_to_av(struct file *file)
1959{
1960 u32 av = 0;
1961
1962 if (file->f_mode & FMODE_READ)
1963 av |= FILE__READ;
1964 if (file->f_mode & FMODE_WRITE) {
1965 if (file->f_flags & O_APPEND)
1966 av |= FILE__APPEND;
1967 else
1968 av |= FILE__WRITE;
1969 }
1970 if (!av) {
1971 /*
1972 * Special file opened with flags 3 for ioctl-only use.
1973 */
1974 av = FILE__IOCTL;
1975 }
1976
1977 return av;
1978}
1979
1980/*
1981 * Convert a file to an access vector and include the correct open
1982 * open permission.
1983 */
1984static inline u32 open_file_to_av(struct file *file)
1985{
1986 u32 av = file_to_av(file);
1987 struct inode *inode = file_inode(file);
1988
1989 if (selinux_policycap_openperm() &&
1990 inode->i_sb->s_magic != SOCKFS_MAGIC)
1991 av |= FILE__OPEN;
1992
1993 return av;
1994}
1995
1996/* Hook functions begin here. */
1997
1998static int selinux_binder_set_context_mgr(struct task_struct *mgr)
1999{
2000 u32 mysid = current_sid();
2001 u32 mgrsid = task_sid(mgr);
2002
2003 return avc_has_perm(&selinux_state,
2004 mysid, mgrsid, SECCLASS_BINDER,
2005 BINDER__SET_CONTEXT_MGR, NULL);
2006}
2007
2008static int selinux_binder_transaction(struct task_struct *from,
2009 struct task_struct *to)
2010{
2011 u32 mysid = current_sid();
2012 u32 fromsid = task_sid(from);
2013 u32 tosid = task_sid(to);
2014 int rc;
2015
2016 if (mysid != fromsid) {
2017 rc = avc_has_perm(&selinux_state,
2018 mysid, fromsid, SECCLASS_BINDER,
2019 BINDER__IMPERSONATE, NULL);
2020 if (rc)
2021 return rc;
2022 }
2023
2024 return avc_has_perm(&selinux_state,
2025 fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2026 NULL);
2027}
2028
2029static int selinux_binder_transfer_binder(struct task_struct *from,
2030 struct task_struct *to)
2031{
2032 u32 fromsid = task_sid(from);
2033 u32 tosid = task_sid(to);
2034
2035 return avc_has_perm(&selinux_state,
2036 fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2037 NULL);
2038}
2039
2040static int selinux_binder_transfer_file(struct task_struct *from,
2041 struct task_struct *to,
2042 struct file *file)
2043{
2044 u32 sid = task_sid(to);
2045 struct file_security_struct *fsec = selinux_file(file);
2046 struct dentry *dentry = file->f_path.dentry;
2047 struct inode_security_struct *isec;
2048 struct common_audit_data ad;
2049 int rc;
2050
2051 ad.type = LSM_AUDIT_DATA_PATH;
2052 ad.u.path = file->f_path;
2053
2054 if (sid != fsec->sid) {
2055 rc = avc_has_perm(&selinux_state,
2056 sid, fsec->sid,
2057 SECCLASS_FD,
2058 FD__USE,
2059 &ad);
2060 if (rc)
2061 return rc;
2062 }
2063
2064#ifdef CONFIG_BPF_SYSCALL
2065 rc = bpf_fd_pass(file, sid);
2066 if (rc)
2067 return rc;
2068#endif
2069
2070 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2071 return 0;
2072
2073 isec = backing_inode_security(dentry);
2074 return avc_has_perm(&selinux_state,
2075 sid, isec->sid, isec->sclass, file_to_av(file),
2076 &ad);
2077}
2078
2079static int selinux_ptrace_access_check(struct task_struct *child,
2080 unsigned int mode)
2081{
2082 u32 sid = current_sid();
2083 u32 csid = task_sid(child);
2084
2085 if (mode & PTRACE_MODE_READ)
2086 return avc_has_perm(&selinux_state,
2087 sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2088
2089 return avc_has_perm(&selinux_state,
2090 sid, csid, SECCLASS_PROCESS, PROCESS__PTRACE, NULL);
2091}
2092
2093static int selinux_ptrace_traceme(struct task_struct *parent)
2094{
2095 return avc_has_perm(&selinux_state,
2096 task_sid(parent), current_sid(), SECCLASS_PROCESS,
2097 PROCESS__PTRACE, NULL);
2098}
2099
2100static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2101 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2102{
2103 return avc_has_perm(&selinux_state,
2104 current_sid(), task_sid(target), SECCLASS_PROCESS,
2105 PROCESS__GETCAP, NULL);
2106}
2107
2108static int selinux_capset(struct cred *new, const struct cred *old,
2109 const kernel_cap_t *effective,
2110 const kernel_cap_t *inheritable,
2111 const kernel_cap_t *permitted)
2112{
2113 return avc_has_perm(&selinux_state,
2114 cred_sid(old), cred_sid(new), SECCLASS_PROCESS,
2115 PROCESS__SETCAP, NULL);
2116}
2117
2118/*
2119 * (This comment used to live with the selinux_task_setuid hook,
2120 * which was removed).
2121 *
2122 * Since setuid only affects the current process, and since the SELinux
2123 * controls are not based on the Linux identity attributes, SELinux does not
2124 * need to control this operation. However, SELinux does control the use of
2125 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2126 */
2127
2128static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2129 int cap, unsigned int opts)
2130{
2131 return cred_has_capability(cred, cap, opts, ns == &init_user_ns);
2132}
2133
2134static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2135{
2136 const struct cred *cred = current_cred();
2137 int rc = 0;
2138
2139 if (!sb)
2140 return 0;
2141
2142 switch (cmds) {
2143 case Q_SYNC:
2144 case Q_QUOTAON:
2145 case Q_QUOTAOFF:
2146 case Q_SETINFO:
2147 case Q_SETQUOTA:
2148 case Q_XQUOTAOFF:
2149 case Q_XQUOTAON:
2150 case Q_XSETQLIM:
2151 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2152 break;
2153 case Q_GETFMT:
2154 case Q_GETINFO:
2155 case Q_GETQUOTA:
2156 case Q_XGETQUOTA:
2157 case Q_XGETQSTAT:
2158 case Q_XGETQSTATV:
2159 case Q_XGETNEXTQUOTA:
2160 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2161 break;
2162 default:
2163 rc = 0; /* let the kernel handle invalid cmds */
2164 break;
2165 }
2166 return rc;
2167}
2168
2169static int selinux_quota_on(struct dentry *dentry)
2170{
2171 const struct cred *cred = current_cred();
2172
2173 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2174}
2175
2176static int selinux_syslog(int type)
2177{
2178 switch (type) {
2179 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2180 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2181 return avc_has_perm(&selinux_state,
2182 current_sid(), SECINITSID_KERNEL,
2183 SECCLASS_SYSTEM, SYSTEM__SYSLOG_READ, NULL);
2184 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2185 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2186 /* Set level of messages printed to console */
2187 case SYSLOG_ACTION_CONSOLE_LEVEL:
2188 return avc_has_perm(&selinux_state,
2189 current_sid(), SECINITSID_KERNEL,
2190 SECCLASS_SYSTEM, SYSTEM__SYSLOG_CONSOLE,
2191 NULL);
2192 }
2193 /* All other syslog types */
2194 return avc_has_perm(&selinux_state,
2195 current_sid(), SECINITSID_KERNEL,
2196 SECCLASS_SYSTEM, SYSTEM__SYSLOG_MOD, NULL);
2197}
2198
2199/*
2200 * Check that a process has enough memory to allocate a new virtual
2201 * mapping. 0 means there is enough memory for the allocation to
2202 * succeed and -ENOMEM implies there is not.
2203 *
2204 * Do not audit the selinux permission check, as this is applied to all
2205 * processes that allocate mappings.
2206 */
2207static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2208{
2209 int rc, cap_sys_admin = 0;
2210
2211 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2212 CAP_OPT_NOAUDIT, true);
2213 if (rc == 0)
2214 cap_sys_admin = 1;
2215
2216 return cap_sys_admin;
2217}
2218
2219/* binprm security operations */
2220
2221static u32 ptrace_parent_sid(void)
2222{
2223 u32 sid = 0;
2224 struct task_struct *tracer;
2225
2226 rcu_read_lock();
2227 tracer = ptrace_parent(current);
2228 if (tracer)
2229 sid = task_sid(tracer);
2230 rcu_read_unlock();
2231
2232 return sid;
2233}
2234
2235static int check_nnp_nosuid(const struct linux_binprm *bprm,
2236 const struct task_security_struct *old_tsec,
2237 const struct task_security_struct *new_tsec)
2238{
2239 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2240 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2241 int rc;
2242 u32 av;
2243
2244 if (!nnp && !nosuid)
2245 return 0; /* neither NNP nor nosuid */
2246
2247 if (new_tsec->sid == old_tsec->sid)
2248 return 0; /* No change in credentials */
2249
2250 /*
2251 * If the policy enables the nnp_nosuid_transition policy capability,
2252 * then we permit transitions under NNP or nosuid if the
2253 * policy allows the corresponding permission between
2254 * the old and new contexts.
2255 */
2256 if (selinux_policycap_nnp_nosuid_transition()) {
2257 av = 0;
2258 if (nnp)
2259 av |= PROCESS2__NNP_TRANSITION;
2260 if (nosuid)
2261 av |= PROCESS2__NOSUID_TRANSITION;
2262 rc = avc_has_perm(&selinux_state,
2263 old_tsec->sid, new_tsec->sid,
2264 SECCLASS_PROCESS2, av, NULL);
2265 if (!rc)
2266 return 0;
2267 }
2268
2269 /*
2270 * We also permit NNP or nosuid transitions to bounded SIDs,
2271 * i.e. SIDs that are guaranteed to only be allowed a subset
2272 * of the permissions of the current SID.
2273 */
2274 rc = security_bounded_transition(&selinux_state, old_tsec->sid,
2275 new_tsec->sid);
2276 if (!rc)
2277 return 0;
2278
2279 /*
2280 * On failure, preserve the errno values for NNP vs nosuid.
2281 * NNP: Operation not permitted for caller.
2282 * nosuid: Permission denied to file.
2283 */
2284 if (nnp)
2285 return -EPERM;
2286 return -EACCES;
2287}
2288
2289static int selinux_bprm_creds_for_exec(struct linux_binprm *bprm)
2290{
2291 const struct task_security_struct *old_tsec;
2292 struct task_security_struct *new_tsec;
2293 struct inode_security_struct *isec;
2294 struct common_audit_data ad;
2295 struct inode *inode = file_inode(bprm->file);
2296 int rc;
2297
2298 /* SELinux context only depends on initial program or script and not
2299 * the script interpreter */
2300
2301 old_tsec = selinux_cred(current_cred());
2302 new_tsec = selinux_cred(bprm->cred);
2303 isec = inode_security(inode);
2304
2305 /* Default to the current task SID. */
2306 new_tsec->sid = old_tsec->sid;
2307 new_tsec->osid = old_tsec->sid;
2308
2309 /* Reset fs, key, and sock SIDs on execve. */
2310 new_tsec->create_sid = 0;
2311 new_tsec->keycreate_sid = 0;
2312 new_tsec->sockcreate_sid = 0;
2313
2314 if (old_tsec->exec_sid) {
2315 new_tsec->sid = old_tsec->exec_sid;
2316 /* Reset exec SID on execve. */
2317 new_tsec->exec_sid = 0;
2318
2319 /* Fail on NNP or nosuid if not an allowed transition. */
2320 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2321 if (rc)
2322 return rc;
2323 } else {
2324 /* Check for a default transition on this program. */
2325 rc = security_transition_sid(&selinux_state, old_tsec->sid,
2326 isec->sid, SECCLASS_PROCESS, NULL,
2327 &new_tsec->sid);
2328 if (rc)
2329 return rc;
2330
2331 /*
2332 * Fallback to old SID on NNP or nosuid if not an allowed
2333 * transition.
2334 */
2335 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2336 if (rc)
2337 new_tsec->sid = old_tsec->sid;
2338 }
2339
2340 ad.type = LSM_AUDIT_DATA_FILE;
2341 ad.u.file = bprm->file;
2342
2343 if (new_tsec->sid == old_tsec->sid) {
2344 rc = avc_has_perm(&selinux_state,
2345 old_tsec->sid, isec->sid,
2346 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2347 if (rc)
2348 return rc;
2349 } else {
2350 /* Check permissions for the transition. */
2351 rc = avc_has_perm(&selinux_state,
2352 old_tsec->sid, new_tsec->sid,
2353 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2354 if (rc)
2355 return rc;
2356
2357 rc = avc_has_perm(&selinux_state,
2358 new_tsec->sid, isec->sid,
2359 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2360 if (rc)
2361 return rc;
2362
2363 /* Check for shared state */
2364 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2365 rc = avc_has_perm(&selinux_state,
2366 old_tsec->sid, new_tsec->sid,
2367 SECCLASS_PROCESS, PROCESS__SHARE,
2368 NULL);
2369 if (rc)
2370 return -EPERM;
2371 }
2372
2373 /* Make sure that anyone attempting to ptrace over a task that
2374 * changes its SID has the appropriate permit */
2375 if (bprm->unsafe & LSM_UNSAFE_PTRACE) {
2376 u32 ptsid = ptrace_parent_sid();
2377 if (ptsid != 0) {
2378 rc = avc_has_perm(&selinux_state,
2379 ptsid, new_tsec->sid,
2380 SECCLASS_PROCESS,
2381 PROCESS__PTRACE, NULL);
2382 if (rc)
2383 return -EPERM;
2384 }
2385 }
2386
2387 /* Clear any possibly unsafe personality bits on exec: */
2388 bprm->per_clear |= PER_CLEAR_ON_SETID;
2389
2390 /* Enable secure mode for SIDs transitions unless
2391 the noatsecure permission is granted between
2392 the two SIDs, i.e. ahp returns 0. */
2393 rc = avc_has_perm(&selinux_state,
2394 old_tsec->sid, new_tsec->sid,
2395 SECCLASS_PROCESS, PROCESS__NOATSECURE,
2396 NULL);
2397 bprm->secureexec |= !!rc;
2398 }
2399
2400 return 0;
2401}
2402
2403static int match_file(const void *p, struct file *file, unsigned fd)
2404{
2405 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2406}
2407
2408/* Derived from fs/exec.c:flush_old_files. */
2409static inline void flush_unauthorized_files(const struct cred *cred,
2410 struct files_struct *files)
2411{
2412 struct file *file, *devnull = NULL;
2413 struct tty_struct *tty;
2414 int drop_tty = 0;
2415 unsigned n;
2416
2417 tty = get_current_tty();
2418 if (tty) {
2419 spin_lock(&tty->files_lock);
2420 if (!list_empty(&tty->tty_files)) {
2421 struct tty_file_private *file_priv;
2422
2423 /* Revalidate access to controlling tty.
2424 Use file_path_has_perm on the tty path directly
2425 rather than using file_has_perm, as this particular
2426 open file may belong to another process and we are
2427 only interested in the inode-based check here. */
2428 file_priv = list_first_entry(&tty->tty_files,
2429 struct tty_file_private, list);
2430 file = file_priv->file;
2431 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2432 drop_tty = 1;
2433 }
2434 spin_unlock(&tty->files_lock);
2435 tty_kref_put(tty);
2436 }
2437 /* Reset controlling tty. */
2438 if (drop_tty)
2439 no_tty();
2440
2441 /* Revalidate access to inherited open files. */
2442 n = iterate_fd(files, 0, match_file, cred);
2443 if (!n) /* none found? */
2444 return;
2445
2446 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2447 if (IS_ERR(devnull))
2448 devnull = NULL;
2449 /* replace all the matching ones with this */
2450 do {
2451 replace_fd(n - 1, devnull, 0);
2452 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2453 if (devnull)
2454 fput(devnull);
2455}
2456
2457/*
2458 * Prepare a process for imminent new credential changes due to exec
2459 */
2460static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2461{
2462 struct task_security_struct *new_tsec;
2463 struct rlimit *rlim, *initrlim;
2464 int rc, i;
2465
2466 new_tsec = selinux_cred(bprm->cred);
2467 if (new_tsec->sid == new_tsec->osid)
2468 return;
2469
2470 /* Close files for which the new task SID is not authorized. */
2471 flush_unauthorized_files(bprm->cred, current->files);
2472
2473 /* Always clear parent death signal on SID transitions. */
2474 current->pdeath_signal = 0;
2475
2476 /* Check whether the new SID can inherit resource limits from the old
2477 * SID. If not, reset all soft limits to the lower of the current
2478 * task's hard limit and the init task's soft limit.
2479 *
2480 * Note that the setting of hard limits (even to lower them) can be
2481 * controlled by the setrlimit check. The inclusion of the init task's
2482 * soft limit into the computation is to avoid resetting soft limits
2483 * higher than the default soft limit for cases where the default is
2484 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2485 */
2486 rc = avc_has_perm(&selinux_state,
2487 new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2488 PROCESS__RLIMITINH, NULL);
2489 if (rc) {
2490 /* protect against do_prlimit() */
2491 task_lock(current);
2492 for (i = 0; i < RLIM_NLIMITS; i++) {
2493 rlim = current->signal->rlim + i;
2494 initrlim = init_task.signal->rlim + i;
2495 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2496 }
2497 task_unlock(current);
2498 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2499 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2500 }
2501}
2502
2503/*
2504 * Clean up the process immediately after the installation of new credentials
2505 * due to exec
2506 */
2507static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2508{
2509 const struct task_security_struct *tsec = selinux_cred(current_cred());
2510 u32 osid, sid;
2511 int rc;
2512
2513 osid = tsec->osid;
2514 sid = tsec->sid;
2515
2516 if (sid == osid)
2517 return;
2518
2519 /* Check whether the new SID can inherit signal state from the old SID.
2520 * If not, clear itimers to avoid subsequent signal generation and
2521 * flush and unblock signals.
2522 *
2523 * This must occur _after_ the task SID has been updated so that any
2524 * kill done after the flush will be checked against the new SID.
2525 */
2526 rc = avc_has_perm(&selinux_state,
2527 osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2528 if (rc) {
2529 clear_itimer();
2530
2531 spin_lock_irq(¤t->sighand->siglock);
2532 if (!fatal_signal_pending(current)) {
2533 flush_sigqueue(¤t->pending);
2534 flush_sigqueue(¤t->signal->shared_pending);
2535 flush_signal_handlers(current, 1);
2536 sigemptyset(¤t->blocked);
2537 recalc_sigpending();
2538 }
2539 spin_unlock_irq(¤t->sighand->siglock);
2540 }
2541
2542 /* Wake up the parent if it is waiting so that it can recheck
2543 * wait permission to the new task SID. */
2544 read_lock(&tasklist_lock);
2545 __wake_up_parent(current, current->real_parent);
2546 read_unlock(&tasklist_lock);
2547}
2548
2549/* superblock security operations */
2550
2551static int selinux_sb_alloc_security(struct super_block *sb)
2552{
2553 struct superblock_security_struct *sbsec;
2554
2555 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
2556 if (!sbsec)
2557 return -ENOMEM;
2558
2559 mutex_init(&sbsec->lock);
2560 INIT_LIST_HEAD(&sbsec->isec_head);
2561 spin_lock_init(&sbsec->isec_lock);
2562 sbsec->sb = sb;
2563 sbsec->sid = SECINITSID_UNLABELED;
2564 sbsec->def_sid = SECINITSID_FILE;
2565 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
2566 sb->s_security = sbsec;
2567
2568 return 0;
2569}
2570
2571static void selinux_sb_free_security(struct super_block *sb)
2572{
2573 superblock_free_security(sb);
2574}
2575
2576static inline int opt_len(const char *s)
2577{
2578 bool open_quote = false;
2579 int len;
2580 char c;
2581
2582 for (len = 0; (c = s[len]) != '\0'; len++) {
2583 if (c == '"')
2584 open_quote = !open_quote;
2585 if (c == ',' && !open_quote)
2586 break;
2587 }
2588 return len;
2589}
2590
2591static int selinux_sb_eat_lsm_opts(char *options, void **mnt_opts)
2592{
2593 char *from = options;
2594 char *to = options;
2595 bool first = true;
2596 int rc;
2597
2598 while (1) {
2599 int len = opt_len(from);
2600 int token;
2601 char *arg = NULL;
2602
2603 token = match_opt_prefix(from, len, &arg);
2604
2605 if (token != Opt_error) {
2606 char *p, *q;
2607
2608 /* strip quotes */
2609 if (arg) {
2610 for (p = q = arg; p < from + len; p++) {
2611 char c = *p;
2612 if (c != '"')
2613 *q++ = c;
2614 }
2615 arg = kmemdup_nul(arg, q - arg, GFP_KERNEL);
2616 if (!arg) {
2617 rc = -ENOMEM;
2618 goto free_opt;
2619 }
2620 }
2621 rc = selinux_add_opt(token, arg, mnt_opts);
2622 if (unlikely(rc)) {
2623 kfree(arg);
2624 goto free_opt;
2625 }
2626 } else {
2627 if (!first) { // copy with preceding comma
2628 from--;
2629 len++;
2630 }
2631 if (to != from)
2632 memmove(to, from, len);
2633 to += len;
2634 first = false;
2635 }
2636 if (!from[len])
2637 break;
2638 from += len + 1;
2639 }
2640 *to = '\0';
2641 return 0;
2642
2643free_opt:
2644 if (*mnt_opts) {
2645 selinux_free_mnt_opts(*mnt_opts);
2646 *mnt_opts = NULL;
2647 }
2648 return rc;
2649}
2650
2651static int selinux_sb_remount(struct super_block *sb, void *mnt_opts)
2652{
2653 struct selinux_mnt_opts *opts = mnt_opts;
2654 struct superblock_security_struct *sbsec = sb->s_security;
2655 u32 sid;
2656 int rc;
2657
2658 if (!(sbsec->flags & SE_SBINITIALIZED))
2659 return 0;
2660
2661 if (!opts)
2662 return 0;
2663
2664 if (opts->fscontext) {
2665 rc = parse_sid(sb, opts->fscontext, &sid);
2666 if (rc)
2667 return rc;
2668 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2669 goto out_bad_option;
2670 }
2671 if (opts->context) {
2672 rc = parse_sid(sb, opts->context, &sid);
2673 if (rc)
2674 return rc;
2675 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2676 goto out_bad_option;
2677 }
2678 if (opts->rootcontext) {
2679 struct inode_security_struct *root_isec;
2680 root_isec = backing_inode_security(sb->s_root);
2681 rc = parse_sid(sb, opts->rootcontext, &sid);
2682 if (rc)
2683 return rc;
2684 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2685 goto out_bad_option;
2686 }
2687 if (opts->defcontext) {
2688 rc = parse_sid(sb, opts->defcontext, &sid);
2689 if (rc)
2690 return rc;
2691 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2692 goto out_bad_option;
2693 }
2694 return 0;
2695
2696out_bad_option:
2697 pr_warn("SELinux: unable to change security options "
2698 "during remount (dev %s, type=%s)\n", sb->s_id,
2699 sb->s_type->name);
2700 return -EINVAL;
2701}
2702
2703static int selinux_sb_kern_mount(struct super_block *sb)
2704{
2705 const struct cred *cred = current_cred();
2706 struct common_audit_data ad;
2707
2708 ad.type = LSM_AUDIT_DATA_DENTRY;
2709 ad.u.dentry = sb->s_root;
2710 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2711}
2712
2713static int selinux_sb_statfs(struct dentry *dentry)
2714{
2715 const struct cred *cred = current_cred();
2716 struct common_audit_data ad;
2717
2718 ad.type = LSM_AUDIT_DATA_DENTRY;
2719 ad.u.dentry = dentry->d_sb->s_root;
2720 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2721}
2722
2723static int selinux_mount(const char *dev_name,
2724 const struct path *path,
2725 const char *type,
2726 unsigned long flags,
2727 void *data)
2728{
2729 const struct cred *cred = current_cred();
2730
2731 if (flags & MS_REMOUNT)
2732 return superblock_has_perm(cred, path->dentry->d_sb,
2733 FILESYSTEM__REMOUNT, NULL);
2734 else
2735 return path_has_perm(cred, path, FILE__MOUNTON);
2736}
2737
2738static int selinux_move_mount(const struct path *from_path,
2739 const struct path *to_path)
2740{
2741 const struct cred *cred = current_cred();
2742
2743 return path_has_perm(cred, to_path, FILE__MOUNTON);
2744}
2745
2746static int selinux_umount(struct vfsmount *mnt, int flags)
2747{
2748 const struct cred *cred = current_cred();
2749
2750 return superblock_has_perm(cred, mnt->mnt_sb,
2751 FILESYSTEM__UNMOUNT, NULL);
2752}
2753
2754static int selinux_fs_context_dup(struct fs_context *fc,
2755 struct fs_context *src_fc)
2756{
2757 const struct selinux_mnt_opts *src = src_fc->security;
2758 struct selinux_mnt_opts *opts;
2759
2760 if (!src)
2761 return 0;
2762
2763 fc->security = kzalloc(sizeof(struct selinux_mnt_opts), GFP_KERNEL);
2764 if (!fc->security)
2765 return -ENOMEM;
2766
2767 opts = fc->security;
2768
2769 if (src->fscontext) {
2770 opts->fscontext = kstrdup(src->fscontext, GFP_KERNEL);
2771 if (!opts->fscontext)
2772 return -ENOMEM;
2773 }
2774 if (src->context) {
2775 opts->context = kstrdup(src->context, GFP_KERNEL);
2776 if (!opts->context)
2777 return -ENOMEM;
2778 }
2779 if (src->rootcontext) {
2780 opts->rootcontext = kstrdup(src->rootcontext, GFP_KERNEL);
2781 if (!opts->rootcontext)
2782 return -ENOMEM;
2783 }
2784 if (src->defcontext) {
2785 opts->defcontext = kstrdup(src->defcontext, GFP_KERNEL);
2786 if (!opts->defcontext)
2787 return -ENOMEM;
2788 }
2789 return 0;
2790}
2791
2792static const struct fs_parameter_spec selinux_fs_parameters[] = {
2793 fsparam_string(CONTEXT_STR, Opt_context),
2794 fsparam_string(DEFCONTEXT_STR, Opt_defcontext),
2795 fsparam_string(FSCONTEXT_STR, Opt_fscontext),
2796 fsparam_string(ROOTCONTEXT_STR, Opt_rootcontext),
2797 fsparam_flag (SECLABEL_STR, Opt_seclabel),
2798 {}
2799};
2800
2801static int selinux_fs_context_parse_param(struct fs_context *fc,
2802 struct fs_parameter *param)
2803{
2804 struct fs_parse_result result;
2805 int opt, rc;
2806
2807 opt = fs_parse(fc, selinux_fs_parameters, param, &result);
2808 if (opt < 0)
2809 return opt;
2810
2811 rc = selinux_add_opt(opt, param->string, &fc->security);
2812 if (!rc) {
2813 param->string = NULL;
2814 rc = 1;
2815 }
2816 return rc;
2817}
2818
2819/* inode security operations */
2820
2821static int selinux_inode_alloc_security(struct inode *inode)
2822{
2823 struct inode_security_struct *isec = selinux_inode(inode);
2824 u32 sid = current_sid();
2825
2826 spin_lock_init(&isec->lock);
2827 INIT_LIST_HEAD(&isec->list);
2828 isec->inode = inode;
2829 isec->sid = SECINITSID_UNLABELED;
2830 isec->sclass = SECCLASS_FILE;
2831 isec->task_sid = sid;
2832 isec->initialized = LABEL_INVALID;
2833
2834 return 0;
2835}
2836
2837static void selinux_inode_free_security(struct inode *inode)
2838{
2839 inode_free_security(inode);
2840}
2841
2842static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2843 const struct qstr *name, void **ctx,
2844 u32 *ctxlen)
2845{
2846 u32 newsid;
2847 int rc;
2848
2849 rc = selinux_determine_inode_label(selinux_cred(current_cred()),
2850 d_inode(dentry->d_parent), name,
2851 inode_mode_to_security_class(mode),
2852 &newsid);
2853 if (rc)
2854 return rc;
2855
2856 return security_sid_to_context(&selinux_state, newsid, (char **)ctx,
2857 ctxlen);
2858}
2859
2860static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2861 struct qstr *name,
2862 const struct cred *old,
2863 struct cred *new)
2864{
2865 u32 newsid;
2866 int rc;
2867 struct task_security_struct *tsec;
2868
2869 rc = selinux_determine_inode_label(selinux_cred(old),
2870 d_inode(dentry->d_parent), name,
2871 inode_mode_to_security_class(mode),
2872 &newsid);
2873 if (rc)
2874 return rc;
2875
2876 tsec = selinux_cred(new);
2877 tsec->create_sid = newsid;
2878 return 0;
2879}
2880
2881static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2882 const struct qstr *qstr,
2883 const char **name,
2884 void **value, size_t *len)
2885{
2886 const struct task_security_struct *tsec = selinux_cred(current_cred());
2887 struct superblock_security_struct *sbsec;
2888 u32 newsid, clen;
2889 int rc;
2890 char *context;
2891
2892 sbsec = dir->i_sb->s_security;
2893
2894 newsid = tsec->create_sid;
2895
2896 rc = selinux_determine_inode_label(tsec, dir, qstr,
2897 inode_mode_to_security_class(inode->i_mode),
2898 &newsid);
2899 if (rc)
2900 return rc;
2901
2902 /* Possibly defer initialization to selinux_complete_init. */
2903 if (sbsec->flags & SE_SBINITIALIZED) {
2904 struct inode_security_struct *isec = selinux_inode(inode);
2905 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2906 isec->sid = newsid;
2907 isec->initialized = LABEL_INITIALIZED;
2908 }
2909
2910 if (!selinux_initialized(&selinux_state) ||
2911 !(sbsec->flags & SBLABEL_MNT))
2912 return -EOPNOTSUPP;
2913
2914 if (name)
2915 *name = XATTR_SELINUX_SUFFIX;
2916
2917 if (value && len) {
2918 rc = security_sid_to_context_force(&selinux_state, newsid,
2919 &context, &clen);
2920 if (rc)
2921 return rc;
2922 *value = context;
2923 *len = clen;
2924 }
2925
2926 return 0;
2927}
2928
2929static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2930{
2931 return may_create(dir, dentry, SECCLASS_FILE);
2932}
2933
2934static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2935{
2936 return may_link(dir, old_dentry, MAY_LINK);
2937}
2938
2939static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2940{
2941 return may_link(dir, dentry, MAY_UNLINK);
2942}
2943
2944static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2945{
2946 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2947}
2948
2949static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2950{
2951 return may_create(dir, dentry, SECCLASS_DIR);
2952}
2953
2954static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2955{
2956 return may_link(dir, dentry, MAY_RMDIR);
2957}
2958
2959static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2960{
2961 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2962}
2963
2964static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2965 struct inode *new_inode, struct dentry *new_dentry)
2966{
2967 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2968}
2969
2970static int selinux_inode_readlink(struct dentry *dentry)
2971{
2972 const struct cred *cred = current_cred();
2973
2974 return dentry_has_perm(cred, dentry, FILE__READ);
2975}
2976
2977static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2978 bool rcu)
2979{
2980 const struct cred *cred = current_cred();
2981 struct common_audit_data ad;
2982 struct inode_security_struct *isec;
2983 u32 sid;
2984
2985 validate_creds(cred);
2986
2987 ad.type = LSM_AUDIT_DATA_DENTRY;
2988 ad.u.dentry = dentry;
2989 sid = cred_sid(cred);
2990 isec = inode_security_rcu(inode, rcu);
2991 if (IS_ERR(isec))
2992 return PTR_ERR(isec);
2993
2994 return avc_has_perm_flags(&selinux_state,
2995 sid, isec->sid, isec->sclass, FILE__READ, &ad,
2996 rcu ? MAY_NOT_BLOCK : 0);
2997}
2998
2999static noinline int audit_inode_permission(struct inode *inode,
3000 u32 perms, u32 audited, u32 denied,
3001 int result)
3002{
3003 struct common_audit_data ad;
3004 struct inode_security_struct *isec = selinux_inode(inode);
3005 int rc;
3006
3007 ad.type = LSM_AUDIT_DATA_INODE;
3008 ad.u.inode = inode;
3009
3010 rc = slow_avc_audit(&selinux_state,
3011 current_sid(), isec->sid, isec->sclass, perms,
3012 audited, denied, result, &ad);
3013 if (rc)
3014 return rc;
3015 return 0;
3016}
3017
3018static int selinux_inode_permission(struct inode *inode, int mask)
3019{
3020 const struct cred *cred = current_cred();
3021 u32 perms;
3022 bool from_access;
3023 bool no_block = mask & MAY_NOT_BLOCK;
3024 struct inode_security_struct *isec;
3025 u32 sid;
3026 struct av_decision avd;
3027 int rc, rc2;
3028 u32 audited, denied;
3029
3030 from_access = mask & MAY_ACCESS;
3031 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3032
3033 /* No permission to check. Existence test. */
3034 if (!mask)
3035 return 0;
3036
3037 validate_creds(cred);
3038
3039 if (unlikely(IS_PRIVATE(inode)))
3040 return 0;
3041
3042 perms = file_mask_to_av(inode->i_mode, mask);
3043
3044 sid = cred_sid(cred);
3045 isec = inode_security_rcu(inode, no_block);
3046 if (IS_ERR(isec))
3047 return PTR_ERR(isec);
3048
3049 rc = avc_has_perm_noaudit(&selinux_state,
3050 sid, isec->sid, isec->sclass, perms,
3051 no_block ? AVC_NONBLOCKING : 0,
3052 &avd);
3053 audited = avc_audit_required(perms, &avd, rc,
3054 from_access ? FILE__AUDIT_ACCESS : 0,
3055 &denied);
3056 if (likely(!audited))
3057 return rc;
3058
3059 /* fall back to ref-walk if we have to generate audit */
3060 if (no_block)
3061 return -ECHILD;
3062
3063 rc2 = audit_inode_permission(inode, perms, audited, denied, rc);
3064 if (rc2)
3065 return rc2;
3066 return rc;
3067}
3068
3069static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3070{
3071 const struct cred *cred = current_cred();
3072 struct inode *inode = d_backing_inode(dentry);
3073 unsigned int ia_valid = iattr->ia_valid;
3074 __u32 av = FILE__WRITE;
3075
3076 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3077 if (ia_valid & ATTR_FORCE) {
3078 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3079 ATTR_FORCE);
3080 if (!ia_valid)
3081 return 0;
3082 }
3083
3084 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3085 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3086 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3087
3088 if (selinux_policycap_openperm() &&
3089 inode->i_sb->s_magic != SOCKFS_MAGIC &&
3090 (ia_valid & ATTR_SIZE) &&
3091 !(ia_valid & ATTR_FILE))
3092 av |= FILE__OPEN;
3093
3094 return dentry_has_perm(cred, dentry, av);
3095}
3096
3097static int selinux_inode_getattr(const struct path *path)
3098{
3099 return path_has_perm(current_cred(), path, FILE__GETATTR);
3100}
3101
3102static bool has_cap_mac_admin(bool audit)
3103{
3104 const struct cred *cred = current_cred();
3105 unsigned int opts = audit ? CAP_OPT_NONE : CAP_OPT_NOAUDIT;
3106
3107 if (cap_capable(cred, &init_user_ns, CAP_MAC_ADMIN, opts))
3108 return false;
3109 if (cred_has_capability(cred, CAP_MAC_ADMIN, opts, true))
3110 return false;
3111 return true;
3112}
3113
3114static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115 const void *value, size_t size, int flags)
3116{
3117 struct inode *inode = d_backing_inode(dentry);
3118 struct inode_security_struct *isec;
3119 struct superblock_security_struct *sbsec;
3120 struct common_audit_data ad;
3121 u32 newsid, sid = current_sid();
3122 int rc = 0;
3123
3124 if (strcmp(name, XATTR_NAME_SELINUX)) {
3125 rc = cap_inode_setxattr(dentry, name, value, size, flags);
3126 if (rc)
3127 return rc;
3128
3129 /* Not an attribute we recognize, so just check the
3130 ordinary setattr permission. */
3131 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3132 }
3133
3134 if (!selinux_initialized(&selinux_state))
3135 return (inode_owner_or_capable(inode) ? 0 : -EPERM);
3136
3137 sbsec = inode->i_sb->s_security;
3138 if (!(sbsec->flags & SBLABEL_MNT))
3139 return -EOPNOTSUPP;
3140
3141 if (!inode_owner_or_capable(inode))
3142 return -EPERM;
3143
3144 ad.type = LSM_AUDIT_DATA_DENTRY;
3145 ad.u.dentry = dentry;
3146
3147 isec = backing_inode_security(dentry);
3148 rc = avc_has_perm(&selinux_state,
3149 sid, isec->sid, isec->sclass,
3150 FILE__RELABELFROM, &ad);
3151 if (rc)
3152 return rc;
3153
3154 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3155 GFP_KERNEL);
3156 if (rc == -EINVAL) {
3157 if (!has_cap_mac_admin(true)) {
3158 struct audit_buffer *ab;
3159 size_t audit_size;
3160
3161 /* We strip a nul only if it is at the end, otherwise the
3162 * context contains a nul and we should audit that */
3163 if (value) {
3164 const char *str = value;
3165
3166 if (str[size - 1] == '\0')
3167 audit_size = size - 1;
3168 else
3169 audit_size = size;
3170 } else {
3171 audit_size = 0;
3172 }
3173 ab = audit_log_start(audit_context(),
3174 GFP_ATOMIC, AUDIT_SELINUX_ERR);
3175 audit_log_format(ab, "op=setxattr invalid_context=");
3176 audit_log_n_untrustedstring(ab, value, audit_size);
3177 audit_log_end(ab);
3178
3179 return rc;
3180 }
3181 rc = security_context_to_sid_force(&selinux_state, value,
3182 size, &newsid);
3183 }
3184 if (rc)
3185 return rc;
3186
3187 rc = avc_has_perm(&selinux_state,
3188 sid, newsid, isec->sclass,
3189 FILE__RELABELTO, &ad);
3190 if (rc)
3191 return rc;
3192
3193 rc = security_validate_transition(&selinux_state, isec->sid, newsid,
3194 sid, isec->sclass);
3195 if (rc)
3196 return rc;
3197
3198 return avc_has_perm(&selinux_state,
3199 newsid,
3200 sbsec->sid,
3201 SECCLASS_FILESYSTEM,
3202 FILESYSTEM__ASSOCIATE,
3203 &ad);
3204}
3205
3206static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3207 const void *value, size_t size,
3208 int flags)
3209{
3210 struct inode *inode = d_backing_inode(dentry);
3211 struct inode_security_struct *isec;
3212 u32 newsid;
3213 int rc;
3214
3215 if (strcmp(name, XATTR_NAME_SELINUX)) {
3216 /* Not an attribute we recognize, so nothing to do. */
3217 return;
3218 }
3219
3220 if (!selinux_initialized(&selinux_state)) {
3221 /* If we haven't even been initialized, then we can't validate
3222 * against a policy, so leave the label as invalid. It may
3223 * resolve to a valid label on the next revalidation try if
3224 * we've since initialized.
3225 */
3226 return;
3227 }
3228
3229 rc = security_context_to_sid_force(&selinux_state, value, size,
3230 &newsid);
3231 if (rc) {
3232 pr_err("SELinux: unable to map context to SID"
3233 "for (%s, %lu), rc=%d\n",
3234 inode->i_sb->s_id, inode->i_ino, -rc);
3235 return;
3236 }
3237
3238 isec = backing_inode_security(dentry);
3239 spin_lock(&isec->lock);
3240 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3241 isec->sid = newsid;
3242 isec->initialized = LABEL_INITIALIZED;
3243 spin_unlock(&isec->lock);
3244
3245 return;
3246}
3247
3248static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3249{
3250 const struct cred *cred = current_cred();
3251
3252 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3253}
3254
3255static int selinux_inode_listxattr(struct dentry *dentry)
3256{
3257 const struct cred *cred = current_cred();
3258
3259 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3260}
3261
3262static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3263{
3264 if (strcmp(name, XATTR_NAME_SELINUX)) {
3265 int rc = cap_inode_removexattr(dentry, name);
3266 if (rc)
3267 return rc;
3268
3269 /* Not an attribute we recognize, so just check the
3270 ordinary setattr permission. */
3271 return dentry_has_perm(current_cred(), dentry, FILE__SETATTR);
3272 }
3273
3274 /* No one is allowed to remove a SELinux security label.
3275 You can change the label, but all data must be labeled. */
3276 return -EACCES;
3277}
3278
3279static int selinux_path_notify(const struct path *path, u64 mask,
3280 unsigned int obj_type)
3281{
3282 int ret;
3283 u32 perm;
3284
3285 struct common_audit_data ad;
3286
3287 ad.type = LSM_AUDIT_DATA_PATH;
3288 ad.u.path = *path;
3289
3290 /*
3291 * Set permission needed based on the type of mark being set.
3292 * Performs an additional check for sb watches.
3293 */
3294 switch (obj_type) {
3295 case FSNOTIFY_OBJ_TYPE_VFSMOUNT:
3296 perm = FILE__WATCH_MOUNT;
3297 break;
3298 case FSNOTIFY_OBJ_TYPE_SB:
3299 perm = FILE__WATCH_SB;
3300 ret = superblock_has_perm(current_cred(), path->dentry->d_sb,
3301 FILESYSTEM__WATCH, &ad);
3302 if (ret)
3303 return ret;
3304 break;
3305 case FSNOTIFY_OBJ_TYPE_INODE:
3306 perm = FILE__WATCH;
3307 break;
3308 default:
3309 return -EINVAL;
3310 }
3311
3312 /* blocking watches require the file:watch_with_perm permission */
3313 if (mask & (ALL_FSNOTIFY_PERM_EVENTS))
3314 perm |= FILE__WATCH_WITH_PERM;
3315
3316 /* watches on read-like events need the file:watch_reads permission */
3317 if (mask & (FS_ACCESS | FS_ACCESS_PERM | FS_CLOSE_NOWRITE))
3318 perm |= FILE__WATCH_READS;
3319
3320 return path_has_perm(current_cred(), path, perm);
3321}
3322
3323/*
3324 * Copy the inode security context value to the user.
3325 *
3326 * Permission check is handled by selinux_inode_getxattr hook.
3327 */
3328static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3329{
3330 u32 size;
3331 int error;
3332 char *context = NULL;
3333 struct inode_security_struct *isec;
3334
3335 /*
3336 * If we're not initialized yet, then we can't validate contexts, so
3337 * just let vfs_getxattr fall back to using the on-disk xattr.
3338 */
3339 if (!selinux_initialized(&selinux_state) ||
3340 strcmp(name, XATTR_SELINUX_SUFFIX))
3341 return -EOPNOTSUPP;
3342
3343 /*
3344 * If the caller has CAP_MAC_ADMIN, then get the raw context
3345 * value even if it is not defined by current policy; otherwise,
3346 * use the in-core value under current policy.
3347 * Use the non-auditing forms of the permission checks since
3348 * getxattr may be called by unprivileged processes commonly
3349 * and lack of permission just means that we fall back to the
3350 * in-core context value, not a denial.
3351 */
3352 isec = inode_security(inode);
3353 if (has_cap_mac_admin(false))
3354 error = security_sid_to_context_force(&selinux_state,
3355 isec->sid, &context,
3356 &size);
3357 else
3358 error = security_sid_to_context(&selinux_state, isec->sid,
3359 &context, &size);
3360 if (error)
3361 return error;
3362 error = size;
3363 if (alloc) {
3364 *buffer = context;
3365 goto out_nofree;
3366 }
3367 kfree(context);
3368out_nofree:
3369 return error;
3370}
3371
3372static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3373 const void *value, size_t size, int flags)
3374{
3375 struct inode_security_struct *isec = inode_security_novalidate(inode);
3376 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
3377 u32 newsid;
3378 int rc;
3379
3380 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3381 return -EOPNOTSUPP;
3382
3383 if (!(sbsec->flags & SBLABEL_MNT))
3384 return -EOPNOTSUPP;
3385
3386 if (!value || !size)
3387 return -EACCES;
3388
3389 rc = security_context_to_sid(&selinux_state, value, size, &newsid,
3390 GFP_KERNEL);
3391 if (rc)
3392 return rc;
3393
3394 spin_lock(&isec->lock);
3395 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3396 isec->sid = newsid;
3397 isec->initialized = LABEL_INITIALIZED;
3398 spin_unlock(&isec->lock);
3399 return 0;
3400}
3401
3402static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3403{
3404 const int len = sizeof(XATTR_NAME_SELINUX);
3405 if (buffer && len <= buffer_size)
3406 memcpy(buffer, XATTR_NAME_SELINUX, len);
3407 return len;
3408}
3409
3410static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3411{
3412 struct inode_security_struct *isec = inode_security_novalidate(inode);
3413 *secid = isec->sid;
3414}
3415
3416static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3417{
3418 u32 sid;
3419 struct task_security_struct *tsec;
3420 struct cred *new_creds = *new;
3421
3422 if (new_creds == NULL) {
3423 new_creds = prepare_creds();
3424 if (!new_creds)
3425 return -ENOMEM;
3426 }
3427
3428 tsec = selinux_cred(new_creds);
3429 /* Get label from overlay inode and set it in create_sid */
3430 selinux_inode_getsecid(d_inode(src), &sid);
3431 tsec->create_sid = sid;
3432 *new = new_creds;
3433 return 0;
3434}
3435
3436static int selinux_inode_copy_up_xattr(const char *name)
3437{
3438 /* The copy_up hook above sets the initial context on an inode, but we
3439 * don't then want to overwrite it by blindly copying all the lower
3440 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3441 */
3442 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3443 return 1; /* Discard */
3444 /*
3445 * Any other attribute apart from SELINUX is not claimed, supported
3446 * by selinux.
3447 */
3448 return -EOPNOTSUPP;
3449}
3450
3451/* kernfs node operations */
3452
3453static int selinux_kernfs_init_security(struct kernfs_node *kn_dir,
3454 struct kernfs_node *kn)
3455{
3456 const struct task_security_struct *tsec = selinux_cred(current_cred());
3457 u32 parent_sid, newsid, clen;
3458 int rc;
3459 char *context;
3460
3461 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, NULL, 0);
3462 if (rc == -ENODATA)
3463 return 0;
3464 else if (rc < 0)
3465 return rc;
3466
3467 clen = (u32)rc;
3468 context = kmalloc(clen, GFP_KERNEL);
3469 if (!context)
3470 return -ENOMEM;
3471
3472 rc = kernfs_xattr_get(kn_dir, XATTR_NAME_SELINUX, context, clen);
3473 if (rc < 0) {
3474 kfree(context);
3475 return rc;
3476 }
3477
3478 rc = security_context_to_sid(&selinux_state, context, clen, &parent_sid,
3479 GFP_KERNEL);
3480 kfree(context);
3481 if (rc)
3482 return rc;
3483
3484 if (tsec->create_sid) {
3485 newsid = tsec->create_sid;
3486 } else {
3487 u16 secclass = inode_mode_to_security_class(kn->mode);
3488 struct qstr q;
3489
3490 q.name = kn->name;
3491 q.hash_len = hashlen_string(kn_dir, kn->name);
3492
3493 rc = security_transition_sid(&selinux_state, tsec->sid,
3494 parent_sid, secclass, &q,
3495 &newsid);
3496 if (rc)
3497 return rc;
3498 }
3499
3500 rc = security_sid_to_context_force(&selinux_state, newsid,
3501 &context, &clen);
3502 if (rc)
3503 return rc;
3504
3505 rc = kernfs_xattr_set(kn, XATTR_NAME_SELINUX, context, clen,
3506 XATTR_CREATE);
3507 kfree(context);
3508 return rc;
3509}
3510
3511
3512/* file security operations */
3513
3514static int selinux_revalidate_file_permission(struct file *file, int mask)
3515{
3516 const struct cred *cred = current_cred();
3517 struct inode *inode = file_inode(file);
3518
3519 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3520 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3521 mask |= MAY_APPEND;
3522
3523 return file_has_perm(cred, file,
3524 file_mask_to_av(inode->i_mode, mask));
3525}
3526
3527static int selinux_file_permission(struct file *file, int mask)
3528{
3529 struct inode *inode = file_inode(file);
3530 struct file_security_struct *fsec = selinux_file(file);
3531 struct inode_security_struct *isec;
3532 u32 sid = current_sid();
3533
3534 if (!mask)
3535 /* No permission to check. Existence test. */
3536 return 0;
3537
3538 isec = inode_security(inode);
3539 if (sid == fsec->sid && fsec->isid == isec->sid &&
3540 fsec->pseqno == avc_policy_seqno(&selinux_state))
3541 /* No change since file_open check. */
3542 return 0;
3543
3544 return selinux_revalidate_file_permission(file, mask);
3545}
3546
3547static int selinux_file_alloc_security(struct file *file)
3548{
3549 struct file_security_struct *fsec = selinux_file(file);
3550 u32 sid = current_sid();
3551
3552 fsec->sid = sid;
3553 fsec->fown_sid = sid;
3554
3555 return 0;
3556}
3557
3558/*
3559 * Check whether a task has the ioctl permission and cmd
3560 * operation to an inode.
3561 */
3562static int ioctl_has_perm(const struct cred *cred, struct file *file,
3563 u32 requested, u16 cmd)
3564{
3565 struct common_audit_data ad;
3566 struct file_security_struct *fsec = selinux_file(file);
3567 struct inode *inode = file_inode(file);
3568 struct inode_security_struct *isec;
3569 struct lsm_ioctlop_audit ioctl;
3570 u32 ssid = cred_sid(cred);
3571 int rc;
3572 u8 driver = cmd >> 8;
3573 u8 xperm = cmd & 0xff;
3574
3575 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3576 ad.u.op = &ioctl;
3577 ad.u.op->cmd = cmd;
3578 ad.u.op->path = file->f_path;
3579
3580 if (ssid != fsec->sid) {
3581 rc = avc_has_perm(&selinux_state,
3582 ssid, fsec->sid,
3583 SECCLASS_FD,
3584 FD__USE,
3585 &ad);
3586 if (rc)
3587 goto out;
3588 }
3589
3590 if (unlikely(IS_PRIVATE(inode)))
3591 return 0;
3592
3593 isec = inode_security(inode);
3594 rc = avc_has_extended_perms(&selinux_state,
3595 ssid, isec->sid, isec->sclass,
3596 requested, driver, xperm, &ad);
3597out:
3598 return rc;
3599}
3600
3601static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3602 unsigned long arg)
3603{
3604 const struct cred *cred = current_cred();
3605 int error = 0;
3606
3607 switch (cmd) {
3608 case FIONREAD:
3609 case FIBMAP:
3610 case FIGETBSZ:
3611 case FS_IOC_GETFLAGS:
3612 case FS_IOC_GETVERSION:
3613 error = file_has_perm(cred, file, FILE__GETATTR);
3614 break;
3615
3616 case FS_IOC_SETFLAGS:
3617 case FS_IOC_SETVERSION:
3618 error = file_has_perm(cred, file, FILE__SETATTR);
3619 break;
3620
3621 /* sys_ioctl() checks */
3622 case FIONBIO:
3623 case FIOASYNC:
3624 error = file_has_perm(cred, file, 0);
3625 break;
3626
3627 case KDSKBENT:
3628 case KDSKBSENT:
3629 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3630 CAP_OPT_NONE, true);
3631 break;
3632
3633 /* default case assumes that the command will go
3634 * to the file's ioctl() function.
3635 */
3636 default:
3637 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3638 }
3639 return error;
3640}
3641
3642static int default_noexec __ro_after_init;
3643
3644static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3645{
3646 const struct cred *cred = current_cred();
3647 u32 sid = cred_sid(cred);
3648 int rc = 0;
3649
3650 if (default_noexec &&
3651 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3652 (!shared && (prot & PROT_WRITE)))) {
3653 /*
3654 * We are making executable an anonymous mapping or a
3655 * private file mapping that will also be writable.
3656 * This has an additional check.
3657 */
3658 rc = avc_has_perm(&selinux_state,
3659 sid, sid, SECCLASS_PROCESS,
3660 PROCESS__EXECMEM, NULL);
3661 if (rc)
3662 goto error;
3663 }
3664
3665 if (file) {
3666 /* read access is always possible with a mapping */
3667 u32 av = FILE__READ;
3668
3669 /* write access only matters if the mapping is shared */
3670 if (shared && (prot & PROT_WRITE))
3671 av |= FILE__WRITE;
3672
3673 if (prot & PROT_EXEC)
3674 av |= FILE__EXECUTE;
3675
3676 return file_has_perm(cred, file, av);
3677 }
3678
3679error:
3680 return rc;
3681}
3682
3683static int selinux_mmap_addr(unsigned long addr)
3684{
3685 int rc = 0;
3686
3687 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3688 u32 sid = current_sid();
3689 rc = avc_has_perm(&selinux_state,
3690 sid, sid, SECCLASS_MEMPROTECT,
3691 MEMPROTECT__MMAP_ZERO, NULL);
3692 }
3693
3694 return rc;
3695}
3696
3697static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3698 unsigned long prot, unsigned long flags)
3699{
3700 struct common_audit_data ad;
3701 int rc;
3702
3703 if (file) {
3704 ad.type = LSM_AUDIT_DATA_FILE;
3705 ad.u.file = file;
3706 rc = inode_has_perm(current_cred(), file_inode(file),
3707 FILE__MAP, &ad);
3708 if (rc)
3709 return rc;
3710 }
3711
3712 if (selinux_state.checkreqprot)
3713 prot = reqprot;
3714
3715 return file_map_prot_check(file, prot,
3716 (flags & MAP_TYPE) == MAP_SHARED);
3717}
3718
3719static int selinux_file_mprotect(struct vm_area_struct *vma,
3720 unsigned long reqprot,
3721 unsigned long prot)
3722{
3723 const struct cred *cred = current_cred();
3724 u32 sid = cred_sid(cred);
3725
3726 if (selinux_state.checkreqprot)
3727 prot = reqprot;
3728
3729 if (default_noexec &&
3730 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3731 int rc = 0;
3732 if (vma->vm_start >= vma->vm_mm->start_brk &&
3733 vma->vm_end <= vma->vm_mm->brk) {
3734 rc = avc_has_perm(&selinux_state,
3735 sid, sid, SECCLASS_PROCESS,
3736 PROCESS__EXECHEAP, NULL);
3737 } else if (!vma->vm_file &&
3738 ((vma->vm_start <= vma->vm_mm->start_stack &&
3739 vma->vm_end >= vma->vm_mm->start_stack) ||
3740 vma_is_stack_for_current(vma))) {
3741 rc = avc_has_perm(&selinux_state,
3742 sid, sid, SECCLASS_PROCESS,
3743 PROCESS__EXECSTACK, NULL);
3744 } else if (vma->vm_file && vma->anon_vma) {
3745 /*
3746 * We are making executable a file mapping that has
3747 * had some COW done. Since pages might have been
3748 * written, check ability to execute the possibly
3749 * modified content. This typically should only
3750 * occur for text relocations.
3751 */
3752 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3753 }
3754 if (rc)
3755 return rc;
3756 }
3757
3758 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3759}
3760
3761static int selinux_file_lock(struct file *file, unsigned int cmd)
3762{
3763 const struct cred *cred = current_cred();
3764
3765 return file_has_perm(cred, file, FILE__LOCK);
3766}
3767
3768static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3769 unsigned long arg)
3770{
3771 const struct cred *cred = current_cred();
3772 int err = 0;
3773
3774 switch (cmd) {
3775 case F_SETFL:
3776 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3777 err = file_has_perm(cred, file, FILE__WRITE);
3778 break;
3779 }
3780 fallthrough;
3781 case F_SETOWN:
3782 case F_SETSIG:
3783 case F_GETFL:
3784 case F_GETOWN:
3785 case F_GETSIG:
3786 case F_GETOWNER_UIDS:
3787 /* Just check FD__USE permission */
3788 err = file_has_perm(cred, file, 0);
3789 break;
3790 case F_GETLK:
3791 case F_SETLK:
3792 case F_SETLKW:
3793 case F_OFD_GETLK:
3794 case F_OFD_SETLK:
3795 case F_OFD_SETLKW:
3796#if BITS_PER_LONG == 32
3797 case F_GETLK64:
3798 case F_SETLK64:
3799 case F_SETLKW64:
3800#endif
3801 err = file_has_perm(cred, file, FILE__LOCK);
3802 break;
3803 }
3804
3805 return err;
3806}
3807
3808static void selinux_file_set_fowner(struct file *file)
3809{
3810 struct file_security_struct *fsec;
3811
3812 fsec = selinux_file(file);
3813 fsec->fown_sid = current_sid();
3814}
3815
3816static int selinux_file_send_sigiotask(struct task_struct *tsk,
3817 struct fown_struct *fown, int signum)
3818{
3819 struct file *file;
3820 u32 sid = task_sid(tsk);
3821 u32 perm;
3822 struct file_security_struct *fsec;
3823
3824 /* struct fown_struct is never outside the context of a struct file */
3825 file = container_of(fown, struct file, f_owner);
3826
3827 fsec = selinux_file(file);
3828
3829 if (!signum)
3830 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3831 else
3832 perm = signal_to_av(signum);
3833
3834 return avc_has_perm(&selinux_state,
3835 fsec->fown_sid, sid,
3836 SECCLASS_PROCESS, perm, NULL);
3837}
3838
3839static int selinux_file_receive(struct file *file)
3840{
3841 const struct cred *cred = current_cred();
3842
3843 return file_has_perm(cred, file, file_to_av(file));
3844}
3845
3846static int selinux_file_open(struct file *file)
3847{
3848 struct file_security_struct *fsec;
3849 struct inode_security_struct *isec;
3850
3851 fsec = selinux_file(file);
3852 isec = inode_security(file_inode(file));
3853 /*
3854 * Save inode label and policy sequence number
3855 * at open-time so that selinux_file_permission
3856 * can determine whether revalidation is necessary.
3857 * Task label is already saved in the file security
3858 * struct as its SID.
3859 */
3860 fsec->isid = isec->sid;
3861 fsec->pseqno = avc_policy_seqno(&selinux_state);
3862 /*
3863 * Since the inode label or policy seqno may have changed
3864 * between the selinux_inode_permission check and the saving
3865 * of state above, recheck that access is still permitted.
3866 * Otherwise, access might never be revalidated against the
3867 * new inode label or new policy.
3868 * This check is not redundant - do not remove.
3869 */
3870 return file_path_has_perm(file->f_cred, file, open_file_to_av(file));
3871}
3872
3873/* task security operations */
3874
3875static int selinux_task_alloc(struct task_struct *task,
3876 unsigned long clone_flags)
3877{
3878 u32 sid = current_sid();
3879
3880 return avc_has_perm(&selinux_state,
3881 sid, sid, SECCLASS_PROCESS, PROCESS__FORK, NULL);
3882}
3883
3884/*
3885 * prepare a new set of credentials for modification
3886 */
3887static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3888 gfp_t gfp)
3889{
3890 const struct task_security_struct *old_tsec = selinux_cred(old);
3891 struct task_security_struct *tsec = selinux_cred(new);
3892
3893 *tsec = *old_tsec;
3894 return 0;
3895}
3896
3897/*
3898 * transfer the SELinux data to a blank set of creds
3899 */
3900static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3901{
3902 const struct task_security_struct *old_tsec = selinux_cred(old);
3903 struct task_security_struct *tsec = selinux_cred(new);
3904
3905 *tsec = *old_tsec;
3906}
3907
3908static void selinux_cred_getsecid(const struct cred *c, u32 *secid)
3909{
3910 *secid = cred_sid(c);
3911}
3912
3913/*
3914 * set the security data for a kernel service
3915 * - all the creation contexts are set to unlabelled
3916 */
3917static int selinux_kernel_act_as(struct cred *new, u32 secid)
3918{
3919 struct task_security_struct *tsec = selinux_cred(new);
3920 u32 sid = current_sid();
3921 int ret;
3922
3923 ret = avc_has_perm(&selinux_state,
3924 sid, secid,
3925 SECCLASS_KERNEL_SERVICE,
3926 KERNEL_SERVICE__USE_AS_OVERRIDE,
3927 NULL);
3928 if (ret == 0) {
3929 tsec->sid = secid;
3930 tsec->create_sid = 0;
3931 tsec->keycreate_sid = 0;
3932 tsec->sockcreate_sid = 0;
3933 }
3934 return ret;
3935}
3936
3937/*
3938 * set the file creation context in a security record to the same as the
3939 * objective context of the specified inode
3940 */
3941static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3942{
3943 struct inode_security_struct *isec = inode_security(inode);
3944 struct task_security_struct *tsec = selinux_cred(new);
3945 u32 sid = current_sid();
3946 int ret;
3947
3948 ret = avc_has_perm(&selinux_state,
3949 sid, isec->sid,
3950 SECCLASS_KERNEL_SERVICE,
3951 KERNEL_SERVICE__CREATE_FILES_AS,
3952 NULL);
3953
3954 if (ret == 0)
3955 tsec->create_sid = isec->sid;
3956 return ret;
3957}
3958
3959static int selinux_kernel_module_request(char *kmod_name)
3960{
3961 struct common_audit_data ad;
3962
3963 ad.type = LSM_AUDIT_DATA_KMOD;
3964 ad.u.kmod_name = kmod_name;
3965
3966 return avc_has_perm(&selinux_state,
3967 current_sid(), SECINITSID_KERNEL, SECCLASS_SYSTEM,
3968 SYSTEM__MODULE_REQUEST, &ad);
3969}
3970
3971static int selinux_kernel_module_from_file(struct file *file)
3972{
3973 struct common_audit_data ad;
3974 struct inode_security_struct *isec;
3975 struct file_security_struct *fsec;
3976 u32 sid = current_sid();
3977 int rc;
3978
3979 /* init_module */
3980 if (file == NULL)
3981 return avc_has_perm(&selinux_state,
3982 sid, sid, SECCLASS_SYSTEM,
3983 SYSTEM__MODULE_LOAD, NULL);
3984
3985 /* finit_module */
3986
3987 ad.type = LSM_AUDIT_DATA_FILE;
3988 ad.u.file = file;
3989
3990 fsec = selinux_file(file);
3991 if (sid != fsec->sid) {
3992 rc = avc_has_perm(&selinux_state,
3993 sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3994 if (rc)
3995 return rc;
3996 }
3997
3998 isec = inode_security(file_inode(file));
3999 return avc_has_perm(&selinux_state,
4000 sid, isec->sid, SECCLASS_SYSTEM,
4001 SYSTEM__MODULE_LOAD, &ad);
4002}
4003
4004static int selinux_kernel_read_file(struct file *file,
4005 enum kernel_read_file_id id)
4006{
4007 int rc = 0;
4008
4009 switch (id) {
4010 case READING_MODULE:
4011 rc = selinux_kernel_module_from_file(file);
4012 break;
4013 default:
4014 break;
4015 }
4016
4017 return rc;
4018}
4019
4020static int selinux_kernel_load_data(enum kernel_load_data_id id)
4021{
4022 int rc = 0;
4023
4024 switch (id) {
4025 case LOADING_MODULE:
4026 rc = selinux_kernel_module_from_file(NULL);
4027 default:
4028 break;
4029 }
4030
4031 return rc;
4032}
4033
4034static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
4035{
4036 return avc_has_perm(&selinux_state,
4037 current_sid(), task_sid(p), SECCLASS_PROCESS,
4038 PROCESS__SETPGID, NULL);
4039}
4040
4041static int selinux_task_getpgid(struct task_struct *p)
4042{
4043 return avc_has_perm(&selinux_state,
4044 current_sid(), task_sid(p), SECCLASS_PROCESS,
4045 PROCESS__GETPGID, NULL);
4046}
4047
4048static int selinux_task_getsid(struct task_struct *p)
4049{
4050 return avc_has_perm(&selinux_state,
4051 current_sid(), task_sid(p), SECCLASS_PROCESS,
4052 PROCESS__GETSESSION, NULL);
4053}
4054
4055static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
4056{
4057 *secid = task_sid(p);
4058}
4059
4060static int selinux_task_setnice(struct task_struct *p, int nice)
4061{
4062 return avc_has_perm(&selinux_state,
4063 current_sid(), task_sid(p), SECCLASS_PROCESS,
4064 PROCESS__SETSCHED, NULL);
4065}
4066
4067static int selinux_task_setioprio(struct task_struct *p, int ioprio)
4068{
4069 return avc_has_perm(&selinux_state,
4070 current_sid(), task_sid(p), SECCLASS_PROCESS,
4071 PROCESS__SETSCHED, NULL);
4072}
4073
4074static int selinux_task_getioprio(struct task_struct *p)
4075{
4076 return avc_has_perm(&selinux_state,
4077 current_sid(), task_sid(p), SECCLASS_PROCESS,
4078 PROCESS__GETSCHED, NULL);
4079}
4080
4081static int selinux_task_prlimit(const struct cred *cred, const struct cred *tcred,
4082 unsigned int flags)
4083{
4084 u32 av = 0;
4085
4086 if (!flags)
4087 return 0;
4088 if (flags & LSM_PRLIMIT_WRITE)
4089 av |= PROCESS__SETRLIMIT;
4090 if (flags & LSM_PRLIMIT_READ)
4091 av |= PROCESS__GETRLIMIT;
4092 return avc_has_perm(&selinux_state,
4093 cred_sid(cred), cred_sid(tcred),
4094 SECCLASS_PROCESS, av, NULL);
4095}
4096
4097static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
4098 struct rlimit *new_rlim)
4099{
4100 struct rlimit *old_rlim = p->signal->rlim + resource;
4101
4102 /* Control the ability to change the hard limit (whether
4103 lowering or raising it), so that the hard limit can
4104 later be used as a safe reset point for the soft limit
4105 upon context transitions. See selinux_bprm_committing_creds. */
4106 if (old_rlim->rlim_max != new_rlim->rlim_max)
4107 return avc_has_perm(&selinux_state,
4108 current_sid(), task_sid(p),
4109 SECCLASS_PROCESS, PROCESS__SETRLIMIT, NULL);
4110
4111 return 0;
4112}
4113
4114static int selinux_task_setscheduler(struct task_struct *p)
4115{
4116 return avc_has_perm(&selinux_state,
4117 current_sid(), task_sid(p), SECCLASS_PROCESS,
4118 PROCESS__SETSCHED, NULL);
4119}
4120
4121static int selinux_task_getscheduler(struct task_struct *p)
4122{
4123 return avc_has_perm(&selinux_state,
4124 current_sid(), task_sid(p), SECCLASS_PROCESS,
4125 PROCESS__GETSCHED, NULL);
4126}
4127
4128static int selinux_task_movememory(struct task_struct *p)
4129{
4130 return avc_has_perm(&selinux_state,
4131 current_sid(), task_sid(p), SECCLASS_PROCESS,
4132 PROCESS__SETSCHED, NULL);
4133}
4134
4135static int selinux_task_kill(struct task_struct *p, struct kernel_siginfo *info,
4136 int sig, const struct cred *cred)
4137{
4138 u32 secid;
4139 u32 perm;
4140
4141 if (!sig)
4142 perm = PROCESS__SIGNULL; /* null signal; existence test */
4143 else
4144 perm = signal_to_av(sig);
4145 if (!cred)
4146 secid = current_sid();
4147 else
4148 secid = cred_sid(cred);
4149 return avc_has_perm(&selinux_state,
4150 secid, task_sid(p), SECCLASS_PROCESS, perm, NULL);
4151}
4152
4153static void selinux_task_to_inode(struct task_struct *p,
4154 struct inode *inode)
4155{
4156 struct inode_security_struct *isec = selinux_inode(inode);
4157 u32 sid = task_sid(p);
4158
4159 spin_lock(&isec->lock);
4160 isec->sclass = inode_mode_to_security_class(inode->i_mode);
4161 isec->sid = sid;
4162 isec->initialized = LABEL_INITIALIZED;
4163 spin_unlock(&isec->lock);
4164}
4165
4166/* Returns error only if unable to parse addresses */
4167static int selinux_parse_skb_ipv4(struct sk_buff *skb,
4168 struct common_audit_data *ad, u8 *proto)
4169{
4170 int offset, ihlen, ret = -EINVAL;
4171 struct iphdr _iph, *ih;
4172
4173 offset = skb_network_offset(skb);
4174 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
4175 if (ih == NULL)
4176 goto out;
4177
4178 ihlen = ih->ihl * 4;
4179 if (ihlen < sizeof(_iph))
4180 goto out;
4181
4182 ad->u.net->v4info.saddr = ih->saddr;
4183 ad->u.net->v4info.daddr = ih->daddr;
4184 ret = 0;
4185
4186 if (proto)
4187 *proto = ih->protocol;
4188
4189 switch (ih->protocol) {
4190 case IPPROTO_TCP: {
4191 struct tcphdr _tcph, *th;
4192
4193 if (ntohs(ih->frag_off) & IP_OFFSET)
4194 break;
4195
4196 offset += ihlen;
4197 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4198 if (th == NULL)
4199 break;
4200
4201 ad->u.net->sport = th->source;
4202 ad->u.net->dport = th->dest;
4203 break;
4204 }
4205
4206 case IPPROTO_UDP: {
4207 struct udphdr _udph, *uh;
4208
4209 if (ntohs(ih->frag_off) & IP_OFFSET)
4210 break;
4211
4212 offset += ihlen;
4213 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4214 if (uh == NULL)
4215 break;
4216
4217 ad->u.net->sport = uh->source;
4218 ad->u.net->dport = uh->dest;
4219 break;
4220 }
4221
4222 case IPPROTO_DCCP: {
4223 struct dccp_hdr _dccph, *dh;
4224
4225 if (ntohs(ih->frag_off) & IP_OFFSET)
4226 break;
4227
4228 offset += ihlen;
4229 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4230 if (dh == NULL)
4231 break;
4232
4233 ad->u.net->sport = dh->dccph_sport;
4234 ad->u.net->dport = dh->dccph_dport;
4235 break;
4236 }
4237
4238#if IS_ENABLED(CONFIG_IP_SCTP)
4239 case IPPROTO_SCTP: {
4240 struct sctphdr _sctph, *sh;
4241
4242 if (ntohs(ih->frag_off) & IP_OFFSET)
4243 break;
4244
4245 offset += ihlen;
4246 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4247 if (sh == NULL)
4248 break;
4249
4250 ad->u.net->sport = sh->source;
4251 ad->u.net->dport = sh->dest;
4252 break;
4253 }
4254#endif
4255 default:
4256 break;
4257 }
4258out:
4259 return ret;
4260}
4261
4262#if IS_ENABLED(CONFIG_IPV6)
4263
4264/* Returns error only if unable to parse addresses */
4265static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4266 struct common_audit_data *ad, u8 *proto)
4267{
4268 u8 nexthdr;
4269 int ret = -EINVAL, offset;
4270 struct ipv6hdr _ipv6h, *ip6;
4271 __be16 frag_off;
4272
4273 offset = skb_network_offset(skb);
4274 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4275 if (ip6 == NULL)
4276 goto out;
4277
4278 ad->u.net->v6info.saddr = ip6->saddr;
4279 ad->u.net->v6info.daddr = ip6->daddr;
4280 ret = 0;
4281
4282 nexthdr = ip6->nexthdr;
4283 offset += sizeof(_ipv6h);
4284 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4285 if (offset < 0)
4286 goto out;
4287
4288 if (proto)
4289 *proto = nexthdr;
4290
4291 switch (nexthdr) {
4292 case IPPROTO_TCP: {
4293 struct tcphdr _tcph, *th;
4294
4295 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4296 if (th == NULL)
4297 break;
4298
4299 ad->u.net->sport = th->source;
4300 ad->u.net->dport = th->dest;
4301 break;
4302 }
4303
4304 case IPPROTO_UDP: {
4305 struct udphdr _udph, *uh;
4306
4307 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4308 if (uh == NULL)
4309 break;
4310
4311 ad->u.net->sport = uh->source;
4312 ad->u.net->dport = uh->dest;
4313 break;
4314 }
4315
4316 case IPPROTO_DCCP: {
4317 struct dccp_hdr _dccph, *dh;
4318
4319 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4320 if (dh == NULL)
4321 break;
4322
4323 ad->u.net->sport = dh->dccph_sport;
4324 ad->u.net->dport = dh->dccph_dport;
4325 break;
4326 }
4327
4328#if IS_ENABLED(CONFIG_IP_SCTP)
4329 case IPPROTO_SCTP: {
4330 struct sctphdr _sctph, *sh;
4331
4332 sh = skb_header_pointer(skb, offset, sizeof(_sctph), &_sctph);
4333 if (sh == NULL)
4334 break;
4335
4336 ad->u.net->sport = sh->source;
4337 ad->u.net->dport = sh->dest;
4338 break;
4339 }
4340#endif
4341 /* includes fragments */
4342 default:
4343 break;
4344 }
4345out:
4346 return ret;
4347}
4348
4349#endif /* IPV6 */
4350
4351static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4352 char **_addrp, int src, u8 *proto)
4353{
4354 char *addrp;
4355 int ret;
4356
4357 switch (ad->u.net->family) {
4358 case PF_INET:
4359 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4360 if (ret)
4361 goto parse_error;
4362 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4363 &ad->u.net->v4info.daddr);
4364 goto okay;
4365
4366#if IS_ENABLED(CONFIG_IPV6)
4367 case PF_INET6:
4368 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4369 if (ret)
4370 goto parse_error;
4371 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4372 &ad->u.net->v6info.daddr);
4373 goto okay;
4374#endif /* IPV6 */
4375 default:
4376 addrp = NULL;
4377 goto okay;
4378 }
4379
4380parse_error:
4381 pr_warn(
4382 "SELinux: failure in selinux_parse_skb(),"
4383 " unable to parse packet\n");
4384 return ret;
4385
4386okay:
4387 if (_addrp)
4388 *_addrp = addrp;
4389 return 0;
4390}
4391
4392/**
4393 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4394 * @skb: the packet
4395 * @family: protocol family
4396 * @sid: the packet's peer label SID
4397 *
4398 * Description:
4399 * Check the various different forms of network peer labeling and determine
4400 * the peer label/SID for the packet; most of the magic actually occurs in
4401 * the security server function security_net_peersid_cmp(). The function
4402 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4403 * or -EACCES if @sid is invalid due to inconsistencies with the different
4404 * peer labels.
4405 *
4406 */
4407static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4408{
4409 int err;
4410 u32 xfrm_sid;
4411 u32 nlbl_sid;
4412 u32 nlbl_type;
4413
4414 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4415 if (unlikely(err))
4416 return -EACCES;
4417 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4418 if (unlikely(err))
4419 return -EACCES;
4420
4421 err = security_net_peersid_resolve(&selinux_state, nlbl_sid,
4422 nlbl_type, xfrm_sid, sid);
4423 if (unlikely(err)) {
4424 pr_warn(
4425 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4426 " unable to determine packet's peer label\n");
4427 return -EACCES;
4428 }
4429
4430 return 0;
4431}
4432
4433/**
4434 * selinux_conn_sid - Determine the child socket label for a connection
4435 * @sk_sid: the parent socket's SID
4436 * @skb_sid: the packet's SID
4437 * @conn_sid: the resulting connection SID
4438 *
4439 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4440 * combined with the MLS information from @skb_sid in order to create
4441 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4442 * of @sk_sid. Returns zero on success, negative values on failure.
4443 *
4444 */
4445static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4446{
4447 int err = 0;
4448
4449 if (skb_sid != SECSID_NULL)
4450 err = security_sid_mls_copy(&selinux_state, sk_sid, skb_sid,
4451 conn_sid);
4452 else
4453 *conn_sid = sk_sid;
4454
4455 return err;
4456}
4457
4458/* socket security operations */
4459
4460static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4461 u16 secclass, u32 *socksid)
4462{
4463 if (tsec->sockcreate_sid > SECSID_NULL) {
4464 *socksid = tsec->sockcreate_sid;
4465 return 0;
4466 }
4467
4468 return security_transition_sid(&selinux_state, tsec->sid, tsec->sid,
4469 secclass, NULL, socksid);
4470}
4471
4472static int sock_has_perm(struct sock *sk, u32 perms)
4473{
4474 struct sk_security_struct *sksec = sk->sk_security;
4475 struct common_audit_data ad;
4476 struct lsm_network_audit net = {0,};
4477
4478 if (sksec->sid == SECINITSID_KERNEL)
4479 return 0;
4480
4481 ad.type = LSM_AUDIT_DATA_NET;
4482 ad.u.net = &net;
4483 ad.u.net->sk = sk;
4484
4485 return avc_has_perm(&selinux_state,
4486 current_sid(), sksec->sid, sksec->sclass, perms,
4487 &ad);
4488}
4489
4490static int selinux_socket_create(int family, int type,
4491 int protocol, int kern)
4492{
4493 const struct task_security_struct *tsec = selinux_cred(current_cred());
4494 u32 newsid;
4495 u16 secclass;
4496 int rc;
4497
4498 if (kern)
4499 return 0;
4500
4501 secclass = socket_type_to_security_class(family, type, protocol);
4502 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4503 if (rc)
4504 return rc;
4505
4506 return avc_has_perm(&selinux_state,
4507 tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4508}
4509
4510static int selinux_socket_post_create(struct socket *sock, int family,
4511 int type, int protocol, int kern)
4512{
4513 const struct task_security_struct *tsec = selinux_cred(current_cred());
4514 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4515 struct sk_security_struct *sksec;
4516 u16 sclass = socket_type_to_security_class(family, type, protocol);
4517 u32 sid = SECINITSID_KERNEL;
4518 int err = 0;
4519
4520 if (!kern) {
4521 err = socket_sockcreate_sid(tsec, sclass, &sid);
4522 if (err)
4523 return err;
4524 }
4525
4526 isec->sclass = sclass;
4527 isec->sid = sid;
4528 isec->initialized = LABEL_INITIALIZED;
4529
4530 if (sock->sk) {
4531 sksec = sock->sk->sk_security;
4532 sksec->sclass = sclass;
4533 sksec->sid = sid;
4534 /* Allows detection of the first association on this socket */
4535 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4536 sksec->sctp_assoc_state = SCTP_ASSOC_UNSET;
4537
4538 err = selinux_netlbl_socket_post_create(sock->sk, family);
4539 }
4540
4541 return err;
4542}
4543
4544static int selinux_socket_socketpair(struct socket *socka,
4545 struct socket *sockb)
4546{
4547 struct sk_security_struct *sksec_a = socka->sk->sk_security;
4548 struct sk_security_struct *sksec_b = sockb->sk->sk_security;
4549
4550 sksec_a->peer_sid = sksec_b->sid;
4551 sksec_b->peer_sid = sksec_a->sid;
4552
4553 return 0;
4554}
4555
4556/* Range of port numbers used to automatically bind.
4557 Need to determine whether we should perform a name_bind
4558 permission check between the socket and the port number. */
4559
4560static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4561{
4562 struct sock *sk = sock->sk;
4563 struct sk_security_struct *sksec = sk->sk_security;
4564 u16 family;
4565 int err;
4566
4567 err = sock_has_perm(sk, SOCKET__BIND);
4568 if (err)
4569 goto out;
4570
4571 /* If PF_INET or PF_INET6, check name_bind permission for the port. */
4572 family = sk->sk_family;
4573 if (family == PF_INET || family == PF_INET6) {
4574 char *addrp;
4575 struct common_audit_data ad;
4576 struct lsm_network_audit net = {0,};
4577 struct sockaddr_in *addr4 = NULL;
4578 struct sockaddr_in6 *addr6 = NULL;
4579 u16 family_sa;
4580 unsigned short snum;
4581 u32 sid, node_perm;
4582
4583 /*
4584 * sctp_bindx(3) calls via selinux_sctp_bind_connect()
4585 * that validates multiple binding addresses. Because of this
4586 * need to check address->sa_family as it is possible to have
4587 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4588 */
4589 if (addrlen < offsetofend(struct sockaddr, sa_family))
4590 return -EINVAL;
4591 family_sa = address->sa_family;
4592 switch (family_sa) {
4593 case AF_UNSPEC:
4594 case AF_INET:
4595 if (addrlen < sizeof(struct sockaddr_in))
4596 return -EINVAL;
4597 addr4 = (struct sockaddr_in *)address;
4598 if (family_sa == AF_UNSPEC) {
4599 /* see __inet_bind(), we only want to allow
4600 * AF_UNSPEC if the address is INADDR_ANY
4601 */
4602 if (addr4->sin_addr.s_addr != htonl(INADDR_ANY))
4603 goto err_af;
4604 family_sa = AF_INET;
4605 }
4606 snum = ntohs(addr4->sin_port);
4607 addrp = (char *)&addr4->sin_addr.s_addr;
4608 break;
4609 case AF_INET6:
4610 if (addrlen < SIN6_LEN_RFC2133)
4611 return -EINVAL;
4612 addr6 = (struct sockaddr_in6 *)address;
4613 snum = ntohs(addr6->sin6_port);
4614 addrp = (char *)&addr6->sin6_addr.s6_addr;
4615 break;
4616 default:
4617 goto err_af;
4618 }
4619
4620 ad.type = LSM_AUDIT_DATA_NET;
4621 ad.u.net = &net;
4622 ad.u.net->sport = htons(snum);
4623 ad.u.net->family = family_sa;
4624
4625 if (snum) {
4626 int low, high;
4627
4628 inet_get_local_port_range(sock_net(sk), &low, &high);
4629
4630 if (inet_port_requires_bind_service(sock_net(sk), snum) ||
4631 snum < low || snum > high) {
4632 err = sel_netport_sid(sk->sk_protocol,
4633 snum, &sid);
4634 if (err)
4635 goto out;
4636 err = avc_has_perm(&selinux_state,
4637 sksec->sid, sid,
4638 sksec->sclass,
4639 SOCKET__NAME_BIND, &ad);
4640 if (err)
4641 goto out;
4642 }
4643 }
4644
4645 switch (sksec->sclass) {
4646 case SECCLASS_TCP_SOCKET:
4647 node_perm = TCP_SOCKET__NODE_BIND;
4648 break;
4649
4650 case SECCLASS_UDP_SOCKET:
4651 node_perm = UDP_SOCKET__NODE_BIND;
4652 break;
4653
4654 case SECCLASS_DCCP_SOCKET:
4655 node_perm = DCCP_SOCKET__NODE_BIND;
4656 break;
4657
4658 case SECCLASS_SCTP_SOCKET:
4659 node_perm = SCTP_SOCKET__NODE_BIND;
4660 break;
4661
4662 default:
4663 node_perm = RAWIP_SOCKET__NODE_BIND;
4664 break;
4665 }
4666
4667 err = sel_netnode_sid(addrp, family_sa, &sid);
4668 if (err)
4669 goto out;
4670
4671 if (family_sa == AF_INET)
4672 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4673 else
4674 ad.u.net->v6info.saddr = addr6->sin6_addr;
4675
4676 err = avc_has_perm(&selinux_state,
4677 sksec->sid, sid,
4678 sksec->sclass, node_perm, &ad);
4679 if (err)
4680 goto out;
4681 }
4682out:
4683 return err;
4684err_af:
4685 /* Note that SCTP services expect -EINVAL, others -EAFNOSUPPORT. */
4686 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4687 return -EINVAL;
4688 return -EAFNOSUPPORT;
4689}
4690
4691/* This supports connect(2) and SCTP connect services such as sctp_connectx(3)
4692 * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst
4693 */
4694static int selinux_socket_connect_helper(struct socket *sock,
4695 struct sockaddr *address, int addrlen)
4696{
4697 struct sock *sk = sock->sk;
4698 struct sk_security_struct *sksec = sk->sk_security;
4699 int err;
4700
4701 err = sock_has_perm(sk, SOCKET__CONNECT);
4702 if (err)
4703 return err;
4704 if (addrlen < offsetofend(struct sockaddr, sa_family))
4705 return -EINVAL;
4706
4707 /* connect(AF_UNSPEC) has special handling, as it is a documented
4708 * way to disconnect the socket
4709 */
4710 if (address->sa_family == AF_UNSPEC)
4711 return 0;
4712
4713 /*
4714 * If a TCP, DCCP or SCTP socket, check name_connect permission
4715 * for the port.
4716 */
4717 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4718 sksec->sclass == SECCLASS_DCCP_SOCKET ||
4719 sksec->sclass == SECCLASS_SCTP_SOCKET) {
4720 struct common_audit_data ad;
4721 struct lsm_network_audit net = {0,};
4722 struct sockaddr_in *addr4 = NULL;
4723 struct sockaddr_in6 *addr6 = NULL;
4724 unsigned short snum;
4725 u32 sid, perm;
4726
4727 /* sctp_connectx(3) calls via selinux_sctp_bind_connect()
4728 * that validates multiple connect addresses. Because of this
4729 * need to check address->sa_family as it is possible to have
4730 * sk->sk_family = PF_INET6 with addr->sa_family = AF_INET.
4731 */
4732 switch (address->sa_family) {
4733 case AF_INET:
4734 addr4 = (struct sockaddr_in *)address;
4735 if (addrlen < sizeof(struct sockaddr_in))
4736 return -EINVAL;
4737 snum = ntohs(addr4->sin_port);
4738 break;
4739 case AF_INET6:
4740 addr6 = (struct sockaddr_in6 *)address;
4741 if (addrlen < SIN6_LEN_RFC2133)
4742 return -EINVAL;
4743 snum = ntohs(addr6->sin6_port);
4744 break;
4745 default:
4746 /* Note that SCTP services expect -EINVAL, whereas
4747 * others expect -EAFNOSUPPORT.
4748 */
4749 if (sksec->sclass == SECCLASS_SCTP_SOCKET)
4750 return -EINVAL;
4751 else
4752 return -EAFNOSUPPORT;
4753 }
4754
4755 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4756 if (err)
4757 return err;
4758
4759 switch (sksec->sclass) {
4760 case SECCLASS_TCP_SOCKET:
4761 perm = TCP_SOCKET__NAME_CONNECT;
4762 break;
4763 case SECCLASS_DCCP_SOCKET:
4764 perm = DCCP_SOCKET__NAME_CONNECT;
4765 break;
4766 case SECCLASS_SCTP_SOCKET:
4767 perm = SCTP_SOCKET__NAME_CONNECT;
4768 break;
4769 }
4770
4771 ad.type = LSM_AUDIT_DATA_NET;
4772 ad.u.net = &net;
4773 ad.u.net->dport = htons(snum);
4774 ad.u.net->family = address->sa_family;
4775 err = avc_has_perm(&selinux_state,
4776 sksec->sid, sid, sksec->sclass, perm, &ad);
4777 if (err)
4778 return err;
4779 }
4780
4781 return 0;
4782}
4783
4784/* Supports connect(2), see comments in selinux_socket_connect_helper() */
4785static int selinux_socket_connect(struct socket *sock,
4786 struct sockaddr *address, int addrlen)
4787{
4788 int err;
4789 struct sock *sk = sock->sk;
4790
4791 err = selinux_socket_connect_helper(sock, address, addrlen);
4792 if (err)
4793 return err;
4794
4795 return selinux_netlbl_socket_connect(sk, address);
4796}
4797
4798static int selinux_socket_listen(struct socket *sock, int backlog)
4799{
4800 return sock_has_perm(sock->sk, SOCKET__LISTEN);
4801}
4802
4803static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4804{
4805 int err;
4806 struct inode_security_struct *isec;
4807 struct inode_security_struct *newisec;
4808 u16 sclass;
4809 u32 sid;
4810
4811 err = sock_has_perm(sock->sk, SOCKET__ACCEPT);
4812 if (err)
4813 return err;
4814
4815 isec = inode_security_novalidate(SOCK_INODE(sock));
4816 spin_lock(&isec->lock);
4817 sclass = isec->sclass;
4818 sid = isec->sid;
4819 spin_unlock(&isec->lock);
4820
4821 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4822 newisec->sclass = sclass;
4823 newisec->sid = sid;
4824 newisec->initialized = LABEL_INITIALIZED;
4825
4826 return 0;
4827}
4828
4829static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4830 int size)
4831{
4832 return sock_has_perm(sock->sk, SOCKET__WRITE);
4833}
4834
4835static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4836 int size, int flags)
4837{
4838 return sock_has_perm(sock->sk, SOCKET__READ);
4839}
4840
4841static int selinux_socket_getsockname(struct socket *sock)
4842{
4843 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4844}
4845
4846static int selinux_socket_getpeername(struct socket *sock)
4847{
4848 return sock_has_perm(sock->sk, SOCKET__GETATTR);
4849}
4850
4851static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4852{
4853 int err;
4854
4855 err = sock_has_perm(sock->sk, SOCKET__SETOPT);
4856 if (err)
4857 return err;
4858
4859 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4860}
4861
4862static int selinux_socket_getsockopt(struct socket *sock, int level,
4863 int optname)
4864{
4865 return sock_has_perm(sock->sk, SOCKET__GETOPT);
4866}
4867
4868static int selinux_socket_shutdown(struct socket *sock, int how)
4869{
4870 return sock_has_perm(sock->sk, SOCKET__SHUTDOWN);
4871}
4872
4873static int selinux_socket_unix_stream_connect(struct sock *sock,
4874 struct sock *other,
4875 struct sock *newsk)
4876{
4877 struct sk_security_struct *sksec_sock = sock->sk_security;
4878 struct sk_security_struct *sksec_other = other->sk_security;
4879 struct sk_security_struct *sksec_new = newsk->sk_security;
4880 struct common_audit_data ad;
4881 struct lsm_network_audit net = {0,};
4882 int err;
4883
4884 ad.type = LSM_AUDIT_DATA_NET;
4885 ad.u.net = &net;
4886 ad.u.net->sk = other;
4887
4888 err = avc_has_perm(&selinux_state,
4889 sksec_sock->sid, sksec_other->sid,
4890 sksec_other->sclass,
4891 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4892 if (err)
4893 return err;
4894
4895 /* server child socket */
4896 sksec_new->peer_sid = sksec_sock->sid;
4897 err = security_sid_mls_copy(&selinux_state, sksec_other->sid,
4898 sksec_sock->sid, &sksec_new->sid);
4899 if (err)
4900 return err;
4901
4902 /* connecting socket */
4903 sksec_sock->peer_sid = sksec_new->sid;
4904
4905 return 0;
4906}
4907
4908static int selinux_socket_unix_may_send(struct socket *sock,
4909 struct socket *other)
4910{
4911 struct sk_security_struct *ssec = sock->sk->sk_security;
4912 struct sk_security_struct *osec = other->sk->sk_security;
4913 struct common_audit_data ad;
4914 struct lsm_network_audit net = {0,};
4915
4916 ad.type = LSM_AUDIT_DATA_NET;
4917 ad.u.net = &net;
4918 ad.u.net->sk = other->sk;
4919
4920 return avc_has_perm(&selinux_state,
4921 ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4922 &ad);
4923}
4924
4925static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4926 char *addrp, u16 family, u32 peer_sid,
4927 struct common_audit_data *ad)
4928{
4929 int err;
4930 u32 if_sid;
4931 u32 node_sid;
4932
4933 err = sel_netif_sid(ns, ifindex, &if_sid);
4934 if (err)
4935 return err;
4936 err = avc_has_perm(&selinux_state,
4937 peer_sid, if_sid,
4938 SECCLASS_NETIF, NETIF__INGRESS, ad);
4939 if (err)
4940 return err;
4941
4942 err = sel_netnode_sid(addrp, family, &node_sid);
4943 if (err)
4944 return err;
4945 return avc_has_perm(&selinux_state,
4946 peer_sid, node_sid,
4947 SECCLASS_NODE, NODE__RECVFROM, ad);
4948}
4949
4950static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4951 u16 family)
4952{
4953 int err = 0;
4954 struct sk_security_struct *sksec = sk->sk_security;
4955 u32 sk_sid = sksec->sid;
4956 struct common_audit_data ad;
4957 struct lsm_network_audit net = {0,};
4958 char *addrp;
4959
4960 ad.type = LSM_AUDIT_DATA_NET;
4961 ad.u.net = &net;
4962 ad.u.net->netif = skb->skb_iif;
4963 ad.u.net->family = family;
4964 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4965 if (err)
4966 return err;
4967
4968 if (selinux_secmark_enabled()) {
4969 err = avc_has_perm(&selinux_state,
4970 sk_sid, skb->secmark, SECCLASS_PACKET,
4971 PACKET__RECV, &ad);
4972 if (err)
4973 return err;
4974 }
4975
4976 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4977 if (err)
4978 return err;
4979 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4980
4981 return err;
4982}
4983
4984static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4985{
4986 int err;
4987 struct sk_security_struct *sksec = sk->sk_security;
4988 u16 family = sk->sk_family;
4989 u32 sk_sid = sksec->sid;
4990 struct common_audit_data ad;
4991 struct lsm_network_audit net = {0,};
4992 char *addrp;
4993 u8 secmark_active;
4994 u8 peerlbl_active;
4995
4996 if (family != PF_INET && family != PF_INET6)
4997 return 0;
4998
4999 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
5000 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5001 family = PF_INET;
5002
5003 /* If any sort of compatibility mode is enabled then handoff processing
5004 * to the selinux_sock_rcv_skb_compat() function to deal with the
5005 * special handling. We do this in an attempt to keep this function
5006 * as fast and as clean as possible. */
5007 if (!selinux_policycap_netpeer())
5008 return selinux_sock_rcv_skb_compat(sk, skb, family);
5009
5010 secmark_active = selinux_secmark_enabled();
5011 peerlbl_active = selinux_peerlbl_enabled();
5012 if (!secmark_active && !peerlbl_active)
5013 return 0;
5014
5015 ad.type = LSM_AUDIT_DATA_NET;
5016 ad.u.net = &net;
5017 ad.u.net->netif = skb->skb_iif;
5018 ad.u.net->family = family;
5019 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
5020 if (err)
5021 return err;
5022
5023 if (peerlbl_active) {
5024 u32 peer_sid;
5025
5026 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
5027 if (err)
5028 return err;
5029 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
5030 addrp, family, peer_sid, &ad);
5031 if (err) {
5032 selinux_netlbl_err(skb, family, err, 0);
5033 return err;
5034 }
5035 err = avc_has_perm(&selinux_state,
5036 sk_sid, peer_sid, SECCLASS_PEER,
5037 PEER__RECV, &ad);
5038 if (err) {
5039 selinux_netlbl_err(skb, family, err, 0);
5040 return err;
5041 }
5042 }
5043
5044 if (secmark_active) {
5045 err = avc_has_perm(&selinux_state,
5046 sk_sid, skb->secmark, SECCLASS_PACKET,
5047 PACKET__RECV, &ad);
5048 if (err)
5049 return err;
5050 }
5051
5052 return err;
5053}
5054
5055static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
5056 int __user *optlen, unsigned len)
5057{
5058 int err = 0;
5059 char *scontext;
5060 u32 scontext_len;
5061 struct sk_security_struct *sksec = sock->sk->sk_security;
5062 u32 peer_sid = SECSID_NULL;
5063
5064 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
5065 sksec->sclass == SECCLASS_TCP_SOCKET ||
5066 sksec->sclass == SECCLASS_SCTP_SOCKET)
5067 peer_sid = sksec->peer_sid;
5068 if (peer_sid == SECSID_NULL)
5069 return -ENOPROTOOPT;
5070
5071 err = security_sid_to_context(&selinux_state, peer_sid, &scontext,
5072 &scontext_len);
5073 if (err)
5074 return err;
5075
5076 if (scontext_len > len) {
5077 err = -ERANGE;
5078 goto out_len;
5079 }
5080
5081 if (copy_to_user(optval, scontext, scontext_len))
5082 err = -EFAULT;
5083
5084out_len:
5085 if (put_user(scontext_len, optlen))
5086 err = -EFAULT;
5087 kfree(scontext);
5088 return err;
5089}
5090
5091static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
5092{
5093 u32 peer_secid = SECSID_NULL;
5094 u16 family;
5095 struct inode_security_struct *isec;
5096
5097 if (skb && skb->protocol == htons(ETH_P_IP))
5098 family = PF_INET;
5099 else if (skb && skb->protocol == htons(ETH_P_IPV6))
5100 family = PF_INET6;
5101 else if (sock)
5102 family = sock->sk->sk_family;
5103 else
5104 goto out;
5105
5106 if (sock && family == PF_UNIX) {
5107 isec = inode_security_novalidate(SOCK_INODE(sock));
5108 peer_secid = isec->sid;
5109 } else if (skb)
5110 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
5111
5112out:
5113 *secid = peer_secid;
5114 if (peer_secid == SECSID_NULL)
5115 return -EINVAL;
5116 return 0;
5117}
5118
5119static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
5120{
5121 struct sk_security_struct *sksec;
5122
5123 sksec = kzalloc(sizeof(*sksec), priority);
5124 if (!sksec)
5125 return -ENOMEM;
5126
5127 sksec->peer_sid = SECINITSID_UNLABELED;
5128 sksec->sid = SECINITSID_UNLABELED;
5129 sksec->sclass = SECCLASS_SOCKET;
5130 selinux_netlbl_sk_security_reset(sksec);
5131 sk->sk_security = sksec;
5132
5133 return 0;
5134}
5135
5136static void selinux_sk_free_security(struct sock *sk)
5137{
5138 struct sk_security_struct *sksec = sk->sk_security;
5139
5140 sk->sk_security = NULL;
5141 selinux_netlbl_sk_security_free(sksec);
5142 kfree(sksec);
5143}
5144
5145static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
5146{
5147 struct sk_security_struct *sksec = sk->sk_security;
5148 struct sk_security_struct *newsksec = newsk->sk_security;
5149
5150 newsksec->sid = sksec->sid;
5151 newsksec->peer_sid = sksec->peer_sid;
5152 newsksec->sclass = sksec->sclass;
5153
5154 selinux_netlbl_sk_security_reset(newsksec);
5155}
5156
5157static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
5158{
5159 if (!sk)
5160 *secid = SECINITSID_ANY_SOCKET;
5161 else {
5162 struct sk_security_struct *sksec = sk->sk_security;
5163
5164 *secid = sksec->sid;
5165 }
5166}
5167
5168static void selinux_sock_graft(struct sock *sk, struct socket *parent)
5169{
5170 struct inode_security_struct *isec =
5171 inode_security_novalidate(SOCK_INODE(parent));
5172 struct sk_security_struct *sksec = sk->sk_security;
5173
5174 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
5175 sk->sk_family == PF_UNIX)
5176 isec->sid = sksec->sid;
5177 sksec->sclass = isec->sclass;
5178}
5179
5180/* Called whenever SCTP receives an INIT chunk. This happens when an incoming
5181 * connect(2), sctp_connectx(3) or sctp_sendmsg(3) (with no association
5182 * already present).
5183 */
5184static int selinux_sctp_assoc_request(struct sctp_endpoint *ep,
5185 struct sk_buff *skb)
5186{
5187 struct sk_security_struct *sksec = ep->base.sk->sk_security;
5188 struct common_audit_data ad;
5189 struct lsm_network_audit net = {0,};
5190 u8 peerlbl_active;
5191 u32 peer_sid = SECINITSID_UNLABELED;
5192 u32 conn_sid;
5193 int err = 0;
5194
5195 if (!selinux_policycap_extsockclass())
5196 return 0;
5197
5198 peerlbl_active = selinux_peerlbl_enabled();
5199
5200 if (peerlbl_active) {
5201 /* This will return peer_sid = SECSID_NULL if there are
5202 * no peer labels, see security_net_peersid_resolve().
5203 */
5204 err = selinux_skb_peerlbl_sid(skb, ep->base.sk->sk_family,
5205 &peer_sid);
5206 if (err)
5207 return err;
5208
5209 if (peer_sid == SECSID_NULL)
5210 peer_sid = SECINITSID_UNLABELED;
5211 }
5212
5213 if (sksec->sctp_assoc_state == SCTP_ASSOC_UNSET) {
5214 sksec->sctp_assoc_state = SCTP_ASSOC_SET;
5215
5216 /* Here as first association on socket. As the peer SID
5217 * was allowed by peer recv (and the netif/node checks),
5218 * then it is approved by policy and used as the primary
5219 * peer SID for getpeercon(3).
5220 */
5221 sksec->peer_sid = peer_sid;
5222 } else if (sksec->peer_sid != peer_sid) {
5223 /* Other association peer SIDs are checked to enforce
5224 * consistency among the peer SIDs.
5225 */
5226 ad.type = LSM_AUDIT_DATA_NET;
5227 ad.u.net = &net;
5228 ad.u.net->sk = ep->base.sk;
5229 err = avc_has_perm(&selinux_state,
5230 sksec->peer_sid, peer_sid, sksec->sclass,
5231 SCTP_SOCKET__ASSOCIATION, &ad);
5232 if (err)
5233 return err;
5234 }
5235
5236 /* Compute the MLS component for the connection and store
5237 * the information in ep. This will be used by SCTP TCP type
5238 * sockets and peeled off connections as they cause a new
5239 * socket to be generated. selinux_sctp_sk_clone() will then
5240 * plug this into the new socket.
5241 */
5242 err = selinux_conn_sid(sksec->sid, peer_sid, &conn_sid);
5243 if (err)
5244 return err;
5245
5246 ep->secid = conn_sid;
5247 ep->peer_secid = peer_sid;
5248
5249 /* Set any NetLabel labels including CIPSO/CALIPSO options. */
5250 return selinux_netlbl_sctp_assoc_request(ep, skb);
5251}
5252
5253/* Check if sctp IPv4/IPv6 addresses are valid for binding or connecting
5254 * based on their @optname.
5255 */
5256static int selinux_sctp_bind_connect(struct sock *sk, int optname,
5257 struct sockaddr *address,
5258 int addrlen)
5259{
5260 int len, err = 0, walk_size = 0;
5261 void *addr_buf;
5262 struct sockaddr *addr;
5263 struct socket *sock;
5264
5265 if (!selinux_policycap_extsockclass())
5266 return 0;
5267
5268 /* Process one or more addresses that may be IPv4 or IPv6 */
5269 sock = sk->sk_socket;
5270 addr_buf = address;
5271
5272 while (walk_size < addrlen) {
5273 if (walk_size + sizeof(sa_family_t) > addrlen)
5274 return -EINVAL;
5275
5276 addr = addr_buf;
5277 switch (addr->sa_family) {
5278 case AF_UNSPEC:
5279 case AF_INET:
5280 len = sizeof(struct sockaddr_in);
5281 break;
5282 case AF_INET6:
5283 len = sizeof(struct sockaddr_in6);
5284 break;
5285 default:
5286 return -EINVAL;
5287 }
5288
5289 if (walk_size + len > addrlen)
5290 return -EINVAL;
5291
5292 err = -EINVAL;
5293 switch (optname) {
5294 /* Bind checks */
5295 case SCTP_PRIMARY_ADDR:
5296 case SCTP_SET_PEER_PRIMARY_ADDR:
5297 case SCTP_SOCKOPT_BINDX_ADD:
5298 err = selinux_socket_bind(sock, addr, len);
5299 break;
5300 /* Connect checks */
5301 case SCTP_SOCKOPT_CONNECTX:
5302 case SCTP_PARAM_SET_PRIMARY:
5303 case SCTP_PARAM_ADD_IP:
5304 case SCTP_SENDMSG_CONNECT:
5305 err = selinux_socket_connect_helper(sock, addr, len);
5306 if (err)
5307 return err;
5308
5309 /* As selinux_sctp_bind_connect() is called by the
5310 * SCTP protocol layer, the socket is already locked,
5311 * therefore selinux_netlbl_socket_connect_locked() is
5312 * is called here. The situations handled are:
5313 * sctp_connectx(3), sctp_sendmsg(3), sendmsg(2),
5314 * whenever a new IP address is added or when a new
5315 * primary address is selected.
5316 * Note that an SCTP connect(2) call happens before
5317 * the SCTP protocol layer and is handled via
5318 * selinux_socket_connect().
5319 */
5320 err = selinux_netlbl_socket_connect_locked(sk, addr);
5321 break;
5322 }
5323
5324 if (err)
5325 return err;
5326
5327 addr_buf += len;
5328 walk_size += len;
5329 }
5330
5331 return 0;
5332}
5333
5334/* Called whenever a new socket is created by accept(2) or sctp_peeloff(3). */
5335static void selinux_sctp_sk_clone(struct sctp_endpoint *ep, struct sock *sk,
5336 struct sock *newsk)
5337{
5338 struct sk_security_struct *sksec = sk->sk_security;
5339 struct sk_security_struct *newsksec = newsk->sk_security;
5340
5341 /* If policy does not support SECCLASS_SCTP_SOCKET then call
5342 * the non-sctp clone version.
5343 */
5344 if (!selinux_policycap_extsockclass())
5345 return selinux_sk_clone_security(sk, newsk);
5346
5347 newsksec->sid = ep->secid;
5348 newsksec->peer_sid = ep->peer_secid;
5349 newsksec->sclass = sksec->sclass;
5350 selinux_netlbl_sctp_sk_clone(sk, newsk);
5351}
5352
5353static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
5354 struct request_sock *req)
5355{
5356 struct sk_security_struct *sksec = sk->sk_security;
5357 int err;
5358 u16 family = req->rsk_ops->family;
5359 u32 connsid;
5360 u32 peersid;
5361
5362 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
5363 if (err)
5364 return err;
5365 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
5366 if (err)
5367 return err;
5368 req->secid = connsid;
5369 req->peer_secid = peersid;
5370
5371 return selinux_netlbl_inet_conn_request(req, family);
5372}
5373
5374static void selinux_inet_csk_clone(struct sock *newsk,
5375 const struct request_sock *req)
5376{
5377 struct sk_security_struct *newsksec = newsk->sk_security;
5378
5379 newsksec->sid = req->secid;
5380 newsksec->peer_sid = req->peer_secid;
5381 /* NOTE: Ideally, we should also get the isec->sid for the
5382 new socket in sync, but we don't have the isec available yet.
5383 So we will wait until sock_graft to do it, by which
5384 time it will have been created and available. */
5385
5386 /* We don't need to take any sort of lock here as we are the only
5387 * thread with access to newsksec */
5388 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
5389}
5390
5391static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
5392{
5393 u16 family = sk->sk_family;
5394 struct sk_security_struct *sksec = sk->sk_security;
5395
5396 /* handle mapped IPv4 packets arriving via IPv6 sockets */
5397 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
5398 family = PF_INET;
5399
5400 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
5401}
5402
5403static int selinux_secmark_relabel_packet(u32 sid)
5404{
5405 const struct task_security_struct *__tsec;
5406 u32 tsid;
5407
5408 __tsec = selinux_cred(current_cred());
5409 tsid = __tsec->sid;
5410
5411 return avc_has_perm(&selinux_state,
5412 tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO,
5413 NULL);
5414}
5415
5416static void selinux_secmark_refcount_inc(void)
5417{
5418 atomic_inc(&selinux_secmark_refcount);
5419}
5420
5421static void selinux_secmark_refcount_dec(void)
5422{
5423 atomic_dec(&selinux_secmark_refcount);
5424}
5425
5426static void selinux_req_classify_flow(const struct request_sock *req,
5427 struct flowi *fl)
5428{
5429 fl->flowi_secid = req->secid;
5430}
5431
5432static int selinux_tun_dev_alloc_security(void **security)
5433{
5434 struct tun_security_struct *tunsec;
5435
5436 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
5437 if (!tunsec)
5438 return -ENOMEM;
5439 tunsec->sid = current_sid();
5440
5441 *security = tunsec;
5442 return 0;
5443}
5444
5445static void selinux_tun_dev_free_security(void *security)
5446{
5447 kfree(security);
5448}
5449
5450static int selinux_tun_dev_create(void)
5451{
5452 u32 sid = current_sid();
5453
5454 /* we aren't taking into account the "sockcreate" SID since the socket
5455 * that is being created here is not a socket in the traditional sense,
5456 * instead it is a private sock, accessible only to the kernel, and
5457 * representing a wide range of network traffic spanning multiple
5458 * connections unlike traditional sockets - check the TUN driver to
5459 * get a better understanding of why this socket is special */
5460
5461 return avc_has_perm(&selinux_state,
5462 sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
5463 NULL);
5464}
5465
5466static int selinux_tun_dev_attach_queue(void *security)
5467{
5468 struct tun_security_struct *tunsec = security;
5469
5470 return avc_has_perm(&selinux_state,
5471 current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
5472 TUN_SOCKET__ATTACH_QUEUE, NULL);
5473}
5474
5475static int selinux_tun_dev_attach(struct sock *sk, void *security)
5476{
5477 struct tun_security_struct *tunsec = security;
5478 struct sk_security_struct *sksec = sk->sk_security;
5479
5480 /* we don't currently perform any NetLabel based labeling here and it
5481 * isn't clear that we would want to do so anyway; while we could apply
5482 * labeling without the support of the TUN user the resulting labeled
5483 * traffic from the other end of the connection would almost certainly
5484 * cause confusion to the TUN user that had no idea network labeling
5485 * protocols were being used */
5486
5487 sksec->sid = tunsec->sid;
5488 sksec->sclass = SECCLASS_TUN_SOCKET;
5489
5490 return 0;
5491}
5492
5493static int selinux_tun_dev_open(void *security)
5494{
5495 struct tun_security_struct *tunsec = security;
5496 u32 sid = current_sid();
5497 int err;
5498
5499 err = avc_has_perm(&selinux_state,
5500 sid, tunsec->sid, SECCLASS_TUN_SOCKET,
5501 TUN_SOCKET__RELABELFROM, NULL);
5502 if (err)
5503 return err;
5504 err = avc_has_perm(&selinux_state,
5505 sid, sid, SECCLASS_TUN_SOCKET,
5506 TUN_SOCKET__RELABELTO, NULL);
5507 if (err)
5508 return err;
5509 tunsec->sid = sid;
5510
5511 return 0;
5512}
5513
5514#ifdef CONFIG_NETFILTER
5515
5516static unsigned int selinux_ip_forward(struct sk_buff *skb,
5517 const struct net_device *indev,
5518 u16 family)
5519{
5520 int err;
5521 char *addrp;
5522 u32 peer_sid;
5523 struct common_audit_data ad;
5524 struct lsm_network_audit net = {0,};
5525 u8 secmark_active;
5526 u8 netlbl_active;
5527 u8 peerlbl_active;
5528
5529 if (!selinux_policycap_netpeer())
5530 return NF_ACCEPT;
5531
5532 secmark_active = selinux_secmark_enabled();
5533 netlbl_active = netlbl_enabled();
5534 peerlbl_active = selinux_peerlbl_enabled();
5535 if (!secmark_active && !peerlbl_active)
5536 return NF_ACCEPT;
5537
5538 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5539 return NF_DROP;
5540
5541 ad.type = LSM_AUDIT_DATA_NET;
5542 ad.u.net = &net;
5543 ad.u.net->netif = indev->ifindex;
5544 ad.u.net->family = family;
5545 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5546 return NF_DROP;
5547
5548 if (peerlbl_active) {
5549 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5550 addrp, family, peer_sid, &ad);
5551 if (err) {
5552 selinux_netlbl_err(skb, family, err, 1);
5553 return NF_DROP;
5554 }
5555 }
5556
5557 if (secmark_active)
5558 if (avc_has_perm(&selinux_state,
5559 peer_sid, skb->secmark,
5560 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5561 return NF_DROP;
5562
5563 if (netlbl_active)
5564 /* we do this in the FORWARD path and not the POST_ROUTING
5565 * path because we want to make sure we apply the necessary
5566 * labeling before IPsec is applied so we can leverage AH
5567 * protection */
5568 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5569 return NF_DROP;
5570
5571 return NF_ACCEPT;
5572}
5573
5574static unsigned int selinux_ipv4_forward(void *priv,
5575 struct sk_buff *skb,
5576 const struct nf_hook_state *state)
5577{
5578 return selinux_ip_forward(skb, state->in, PF_INET);
5579}
5580
5581#if IS_ENABLED(CONFIG_IPV6)
5582static unsigned int selinux_ipv6_forward(void *priv,
5583 struct sk_buff *skb,
5584 const struct nf_hook_state *state)
5585{
5586 return selinux_ip_forward(skb, state->in, PF_INET6);
5587}
5588#endif /* IPV6 */
5589
5590static unsigned int selinux_ip_output(struct sk_buff *skb,
5591 u16 family)
5592{
5593 struct sock *sk;
5594 u32 sid;
5595
5596 if (!netlbl_enabled())
5597 return NF_ACCEPT;
5598
5599 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5600 * because we want to make sure we apply the necessary labeling
5601 * before IPsec is applied so we can leverage AH protection */
5602 sk = skb->sk;
5603 if (sk) {
5604 struct sk_security_struct *sksec;
5605
5606 if (sk_listener(sk))
5607 /* if the socket is the listening state then this
5608 * packet is a SYN-ACK packet which means it needs to
5609 * be labeled based on the connection/request_sock and
5610 * not the parent socket. unfortunately, we can't
5611 * lookup the request_sock yet as it isn't queued on
5612 * the parent socket until after the SYN-ACK is sent.
5613 * the "solution" is to simply pass the packet as-is
5614 * as any IP option based labeling should be copied
5615 * from the initial connection request (in the IP
5616 * layer). it is far from ideal, but until we get a
5617 * security label in the packet itself this is the
5618 * best we can do. */
5619 return NF_ACCEPT;
5620
5621 /* standard practice, label using the parent socket */
5622 sksec = sk->sk_security;
5623 sid = sksec->sid;
5624 } else
5625 sid = SECINITSID_KERNEL;
5626 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5627 return NF_DROP;
5628
5629 return NF_ACCEPT;
5630}
5631
5632static unsigned int selinux_ipv4_output(void *priv,
5633 struct sk_buff *skb,
5634 const struct nf_hook_state *state)
5635{
5636 return selinux_ip_output(skb, PF_INET);
5637}
5638
5639#if IS_ENABLED(CONFIG_IPV6)
5640static unsigned int selinux_ipv6_output(void *priv,
5641 struct sk_buff *skb,
5642 const struct nf_hook_state *state)
5643{
5644 return selinux_ip_output(skb, PF_INET6);
5645}
5646#endif /* IPV6 */
5647
5648static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5649 int ifindex,
5650 u16 family)
5651{
5652 struct sock *sk = skb_to_full_sk(skb);
5653 struct sk_security_struct *sksec;
5654 struct common_audit_data ad;
5655 struct lsm_network_audit net = {0,};
5656 char *addrp;
5657 u8 proto;
5658
5659 if (sk == NULL)
5660 return NF_ACCEPT;
5661 sksec = sk->sk_security;
5662
5663 ad.type = LSM_AUDIT_DATA_NET;
5664 ad.u.net = &net;
5665 ad.u.net->netif = ifindex;
5666 ad.u.net->family = family;
5667 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5668 return NF_DROP;
5669
5670 if (selinux_secmark_enabled())
5671 if (avc_has_perm(&selinux_state,
5672 sksec->sid, skb->secmark,
5673 SECCLASS_PACKET, PACKET__SEND, &ad))
5674 return NF_DROP_ERR(-ECONNREFUSED);
5675
5676 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5677 return NF_DROP_ERR(-ECONNREFUSED);
5678
5679 return NF_ACCEPT;
5680}
5681
5682static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5683 const struct net_device *outdev,
5684 u16 family)
5685{
5686 u32 secmark_perm;
5687 u32 peer_sid;
5688 int ifindex = outdev->ifindex;
5689 struct sock *sk;
5690 struct common_audit_data ad;
5691 struct lsm_network_audit net = {0,};
5692 char *addrp;
5693 u8 secmark_active;
5694 u8 peerlbl_active;
5695
5696 /* If any sort of compatibility mode is enabled then handoff processing
5697 * to the selinux_ip_postroute_compat() function to deal with the
5698 * special handling. We do this in an attempt to keep this function
5699 * as fast and as clean as possible. */
5700 if (!selinux_policycap_netpeer())
5701 return selinux_ip_postroute_compat(skb, ifindex, family);
5702
5703 secmark_active = selinux_secmark_enabled();
5704 peerlbl_active = selinux_peerlbl_enabled();
5705 if (!secmark_active && !peerlbl_active)
5706 return NF_ACCEPT;
5707
5708 sk = skb_to_full_sk(skb);
5709
5710#ifdef CONFIG_XFRM
5711 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5712 * packet transformation so allow the packet to pass without any checks
5713 * since we'll have another chance to perform access control checks
5714 * when the packet is on it's final way out.
5715 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5716 * is NULL, in this case go ahead and apply access control.
5717 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5718 * TCP listening state we cannot wait until the XFRM processing
5719 * is done as we will miss out on the SA label if we do;
5720 * unfortunately, this means more work, but it is only once per
5721 * connection. */
5722 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5723 !(sk && sk_listener(sk)))
5724 return NF_ACCEPT;
5725#endif
5726
5727 if (sk == NULL) {
5728 /* Without an associated socket the packet is either coming
5729 * from the kernel or it is being forwarded; check the packet
5730 * to determine which and if the packet is being forwarded
5731 * query the packet directly to determine the security label. */
5732 if (skb->skb_iif) {
5733 secmark_perm = PACKET__FORWARD_OUT;
5734 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5735 return NF_DROP;
5736 } else {
5737 secmark_perm = PACKET__SEND;
5738 peer_sid = SECINITSID_KERNEL;
5739 }
5740 } else if (sk_listener(sk)) {
5741 /* Locally generated packet but the associated socket is in the
5742 * listening state which means this is a SYN-ACK packet. In
5743 * this particular case the correct security label is assigned
5744 * to the connection/request_sock but unfortunately we can't
5745 * query the request_sock as it isn't queued on the parent
5746 * socket until after the SYN-ACK packet is sent; the only
5747 * viable choice is to regenerate the label like we do in
5748 * selinux_inet_conn_request(). See also selinux_ip_output()
5749 * for similar problems. */
5750 u32 skb_sid;
5751 struct sk_security_struct *sksec;
5752
5753 sksec = sk->sk_security;
5754 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5755 return NF_DROP;
5756 /* At this point, if the returned skb peerlbl is SECSID_NULL
5757 * and the packet has been through at least one XFRM
5758 * transformation then we must be dealing with the "final"
5759 * form of labeled IPsec packet; since we've already applied
5760 * all of our access controls on this packet we can safely
5761 * pass the packet. */
5762 if (skb_sid == SECSID_NULL) {
5763 switch (family) {
5764 case PF_INET:
5765 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5766 return NF_ACCEPT;
5767 break;
5768 case PF_INET6:
5769 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5770 return NF_ACCEPT;
5771 break;
5772 default:
5773 return NF_DROP_ERR(-ECONNREFUSED);
5774 }
5775 }
5776 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5777 return NF_DROP;
5778 secmark_perm = PACKET__SEND;
5779 } else {
5780 /* Locally generated packet, fetch the security label from the
5781 * associated socket. */
5782 struct sk_security_struct *sksec = sk->sk_security;
5783 peer_sid = sksec->sid;
5784 secmark_perm = PACKET__SEND;
5785 }
5786
5787 ad.type = LSM_AUDIT_DATA_NET;
5788 ad.u.net = &net;
5789 ad.u.net->netif = ifindex;
5790 ad.u.net->family = family;
5791 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5792 return NF_DROP;
5793
5794 if (secmark_active)
5795 if (avc_has_perm(&selinux_state,
5796 peer_sid, skb->secmark,
5797 SECCLASS_PACKET, secmark_perm, &ad))
5798 return NF_DROP_ERR(-ECONNREFUSED);
5799
5800 if (peerlbl_active) {
5801 u32 if_sid;
5802 u32 node_sid;
5803
5804 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5805 return NF_DROP;
5806 if (avc_has_perm(&selinux_state,
5807 peer_sid, if_sid,
5808 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5809 return NF_DROP_ERR(-ECONNREFUSED);
5810
5811 if (sel_netnode_sid(addrp, family, &node_sid))
5812 return NF_DROP;
5813 if (avc_has_perm(&selinux_state,
5814 peer_sid, node_sid,
5815 SECCLASS_NODE, NODE__SENDTO, &ad))
5816 return NF_DROP_ERR(-ECONNREFUSED);
5817 }
5818
5819 return NF_ACCEPT;
5820}
5821
5822static unsigned int selinux_ipv4_postroute(void *priv,
5823 struct sk_buff *skb,
5824 const struct nf_hook_state *state)
5825{
5826 return selinux_ip_postroute(skb, state->out, PF_INET);
5827}
5828
5829#if IS_ENABLED(CONFIG_IPV6)
5830static unsigned int selinux_ipv6_postroute(void *priv,
5831 struct sk_buff *skb,
5832 const struct nf_hook_state *state)
5833{
5834 return selinux_ip_postroute(skb, state->out, PF_INET6);
5835}
5836#endif /* IPV6 */
5837
5838#endif /* CONFIG_NETFILTER */
5839
5840static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5841{
5842 int rc = 0;
5843 unsigned int msg_len;
5844 unsigned int data_len = skb->len;
5845 unsigned char *data = skb->data;
5846 struct nlmsghdr *nlh;
5847 struct sk_security_struct *sksec = sk->sk_security;
5848 u16 sclass = sksec->sclass;
5849 u32 perm;
5850
5851 while (data_len >= nlmsg_total_size(0)) {
5852 nlh = (struct nlmsghdr *)data;
5853
5854 /* NOTE: the nlmsg_len field isn't reliably set by some netlink
5855 * users which means we can't reject skb's with bogus
5856 * length fields; our solution is to follow what
5857 * netlink_rcv_skb() does and simply skip processing at
5858 * messages with length fields that are clearly junk
5859 */
5860 if (nlh->nlmsg_len < NLMSG_HDRLEN || nlh->nlmsg_len > data_len)
5861 return 0;
5862
5863 rc = selinux_nlmsg_lookup(sclass, nlh->nlmsg_type, &perm);
5864 if (rc == 0) {
5865 rc = sock_has_perm(sk, perm);
5866 if (rc)
5867 return rc;
5868 } else if (rc == -EINVAL) {
5869 /* -EINVAL is a missing msg/perm mapping */
5870 pr_warn_ratelimited("SELinux: unrecognized netlink"
5871 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5872 " pid=%d comm=%s\n",
5873 sk->sk_protocol, nlh->nlmsg_type,
5874 secclass_map[sclass - 1].name,
5875 task_pid_nr(current), current->comm);
5876 if (enforcing_enabled(&selinux_state) &&
5877 !security_get_allow_unknown(&selinux_state))
5878 return rc;
5879 rc = 0;
5880 } else if (rc == -ENOENT) {
5881 /* -ENOENT is a missing socket/class mapping, ignore */
5882 rc = 0;
5883 } else {
5884 return rc;
5885 }
5886
5887 /* move to the next message after applying netlink padding */
5888 msg_len = NLMSG_ALIGN(nlh->nlmsg_len);
5889 if (msg_len >= data_len)
5890 return 0;
5891 data_len -= msg_len;
5892 data += msg_len;
5893 }
5894
5895 return rc;
5896}
5897
5898static void ipc_init_security(struct ipc_security_struct *isec, u16 sclass)
5899{
5900 isec->sclass = sclass;
5901 isec->sid = current_sid();
5902}
5903
5904static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5905 u32 perms)
5906{
5907 struct ipc_security_struct *isec;
5908 struct common_audit_data ad;
5909 u32 sid = current_sid();
5910
5911 isec = selinux_ipc(ipc_perms);
5912
5913 ad.type = LSM_AUDIT_DATA_IPC;
5914 ad.u.ipc_id = ipc_perms->key;
5915
5916 return avc_has_perm(&selinux_state,
5917 sid, isec->sid, isec->sclass, perms, &ad);
5918}
5919
5920static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5921{
5922 struct msg_security_struct *msec;
5923
5924 msec = selinux_msg_msg(msg);
5925 msec->sid = SECINITSID_UNLABELED;
5926
5927 return 0;
5928}
5929
5930/* message queue security operations */
5931static int selinux_msg_queue_alloc_security(struct kern_ipc_perm *msq)
5932{
5933 struct ipc_security_struct *isec;
5934 struct common_audit_data ad;
5935 u32 sid = current_sid();
5936 int rc;
5937
5938 isec = selinux_ipc(msq);
5939 ipc_init_security(isec, SECCLASS_MSGQ);
5940
5941 ad.type = LSM_AUDIT_DATA_IPC;
5942 ad.u.ipc_id = msq->key;
5943
5944 rc = avc_has_perm(&selinux_state,
5945 sid, isec->sid, SECCLASS_MSGQ,
5946 MSGQ__CREATE, &ad);
5947 return rc;
5948}
5949
5950static int selinux_msg_queue_associate(struct kern_ipc_perm *msq, int msqflg)
5951{
5952 struct ipc_security_struct *isec;
5953 struct common_audit_data ad;
5954 u32 sid = current_sid();
5955
5956 isec = selinux_ipc(msq);
5957
5958 ad.type = LSM_AUDIT_DATA_IPC;
5959 ad.u.ipc_id = msq->key;
5960
5961 return avc_has_perm(&selinux_state,
5962 sid, isec->sid, SECCLASS_MSGQ,
5963 MSGQ__ASSOCIATE, &ad);
5964}
5965
5966static int selinux_msg_queue_msgctl(struct kern_ipc_perm *msq, int cmd)
5967{
5968 int err;
5969 int perms;
5970
5971 switch (cmd) {
5972 case IPC_INFO:
5973 case MSG_INFO:
5974 /* No specific object, just general system-wide information. */
5975 return avc_has_perm(&selinux_state,
5976 current_sid(), SECINITSID_KERNEL,
5977 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
5978 case IPC_STAT:
5979 case MSG_STAT:
5980 case MSG_STAT_ANY:
5981 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5982 break;
5983 case IPC_SET:
5984 perms = MSGQ__SETATTR;
5985 break;
5986 case IPC_RMID:
5987 perms = MSGQ__DESTROY;
5988 break;
5989 default:
5990 return 0;
5991 }
5992
5993 err = ipc_has_perm(msq, perms);
5994 return err;
5995}
5996
5997static int selinux_msg_queue_msgsnd(struct kern_ipc_perm *msq, struct msg_msg *msg, int msqflg)
5998{
5999 struct ipc_security_struct *isec;
6000 struct msg_security_struct *msec;
6001 struct common_audit_data ad;
6002 u32 sid = current_sid();
6003 int rc;
6004
6005 isec = selinux_ipc(msq);
6006 msec = selinux_msg_msg(msg);
6007
6008 /*
6009 * First time through, need to assign label to the message
6010 */
6011 if (msec->sid == SECINITSID_UNLABELED) {
6012 /*
6013 * Compute new sid based on current process and
6014 * message queue this message will be stored in
6015 */
6016 rc = security_transition_sid(&selinux_state, sid, isec->sid,
6017 SECCLASS_MSG, NULL, &msec->sid);
6018 if (rc)
6019 return rc;
6020 }
6021
6022 ad.type = LSM_AUDIT_DATA_IPC;
6023 ad.u.ipc_id = msq->key;
6024
6025 /* Can this process write to the queue? */
6026 rc = avc_has_perm(&selinux_state,
6027 sid, isec->sid, SECCLASS_MSGQ,
6028 MSGQ__WRITE, &ad);
6029 if (!rc)
6030 /* Can this process send the message */
6031 rc = avc_has_perm(&selinux_state,
6032 sid, msec->sid, SECCLASS_MSG,
6033 MSG__SEND, &ad);
6034 if (!rc)
6035 /* Can the message be put in the queue? */
6036 rc = avc_has_perm(&selinux_state,
6037 msec->sid, isec->sid, SECCLASS_MSGQ,
6038 MSGQ__ENQUEUE, &ad);
6039
6040 return rc;
6041}
6042
6043static int selinux_msg_queue_msgrcv(struct kern_ipc_perm *msq, struct msg_msg *msg,
6044 struct task_struct *target,
6045 long type, int mode)
6046{
6047 struct ipc_security_struct *isec;
6048 struct msg_security_struct *msec;
6049 struct common_audit_data ad;
6050 u32 sid = task_sid(target);
6051 int rc;
6052
6053 isec = selinux_ipc(msq);
6054 msec = selinux_msg_msg(msg);
6055
6056 ad.type = LSM_AUDIT_DATA_IPC;
6057 ad.u.ipc_id = msq->key;
6058
6059 rc = avc_has_perm(&selinux_state,
6060 sid, isec->sid,
6061 SECCLASS_MSGQ, MSGQ__READ, &ad);
6062 if (!rc)
6063 rc = avc_has_perm(&selinux_state,
6064 sid, msec->sid,
6065 SECCLASS_MSG, MSG__RECEIVE, &ad);
6066 return rc;
6067}
6068
6069/* Shared Memory security operations */
6070static int selinux_shm_alloc_security(struct kern_ipc_perm *shp)
6071{
6072 struct ipc_security_struct *isec;
6073 struct common_audit_data ad;
6074 u32 sid = current_sid();
6075 int rc;
6076
6077 isec = selinux_ipc(shp);
6078 ipc_init_security(isec, SECCLASS_SHM);
6079
6080 ad.type = LSM_AUDIT_DATA_IPC;
6081 ad.u.ipc_id = shp->key;
6082
6083 rc = avc_has_perm(&selinux_state,
6084 sid, isec->sid, SECCLASS_SHM,
6085 SHM__CREATE, &ad);
6086 return rc;
6087}
6088
6089static int selinux_shm_associate(struct kern_ipc_perm *shp, int shmflg)
6090{
6091 struct ipc_security_struct *isec;
6092 struct common_audit_data ad;
6093 u32 sid = current_sid();
6094
6095 isec = selinux_ipc(shp);
6096
6097 ad.type = LSM_AUDIT_DATA_IPC;
6098 ad.u.ipc_id = shp->key;
6099
6100 return avc_has_perm(&selinux_state,
6101 sid, isec->sid, SECCLASS_SHM,
6102 SHM__ASSOCIATE, &ad);
6103}
6104
6105/* Note, at this point, shp is locked down */
6106static int selinux_shm_shmctl(struct kern_ipc_perm *shp, int cmd)
6107{
6108 int perms;
6109 int err;
6110
6111 switch (cmd) {
6112 case IPC_INFO:
6113 case SHM_INFO:
6114 /* No specific object, just general system-wide information. */
6115 return avc_has_perm(&selinux_state,
6116 current_sid(), SECINITSID_KERNEL,
6117 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6118 case IPC_STAT:
6119 case SHM_STAT:
6120 case SHM_STAT_ANY:
6121 perms = SHM__GETATTR | SHM__ASSOCIATE;
6122 break;
6123 case IPC_SET:
6124 perms = SHM__SETATTR;
6125 break;
6126 case SHM_LOCK:
6127 case SHM_UNLOCK:
6128 perms = SHM__LOCK;
6129 break;
6130 case IPC_RMID:
6131 perms = SHM__DESTROY;
6132 break;
6133 default:
6134 return 0;
6135 }
6136
6137 err = ipc_has_perm(shp, perms);
6138 return err;
6139}
6140
6141static int selinux_shm_shmat(struct kern_ipc_perm *shp,
6142 char __user *shmaddr, int shmflg)
6143{
6144 u32 perms;
6145
6146 if (shmflg & SHM_RDONLY)
6147 perms = SHM__READ;
6148 else
6149 perms = SHM__READ | SHM__WRITE;
6150
6151 return ipc_has_perm(shp, perms);
6152}
6153
6154/* Semaphore security operations */
6155static int selinux_sem_alloc_security(struct kern_ipc_perm *sma)
6156{
6157 struct ipc_security_struct *isec;
6158 struct common_audit_data ad;
6159 u32 sid = current_sid();
6160 int rc;
6161
6162 isec = selinux_ipc(sma);
6163 ipc_init_security(isec, SECCLASS_SEM);
6164
6165 ad.type = LSM_AUDIT_DATA_IPC;
6166 ad.u.ipc_id = sma->key;
6167
6168 rc = avc_has_perm(&selinux_state,
6169 sid, isec->sid, SECCLASS_SEM,
6170 SEM__CREATE, &ad);
6171 return rc;
6172}
6173
6174static int selinux_sem_associate(struct kern_ipc_perm *sma, int semflg)
6175{
6176 struct ipc_security_struct *isec;
6177 struct common_audit_data ad;
6178 u32 sid = current_sid();
6179
6180 isec = selinux_ipc(sma);
6181
6182 ad.type = LSM_AUDIT_DATA_IPC;
6183 ad.u.ipc_id = sma->key;
6184
6185 return avc_has_perm(&selinux_state,
6186 sid, isec->sid, SECCLASS_SEM,
6187 SEM__ASSOCIATE, &ad);
6188}
6189
6190/* Note, at this point, sma is locked down */
6191static int selinux_sem_semctl(struct kern_ipc_perm *sma, int cmd)
6192{
6193 int err;
6194 u32 perms;
6195
6196 switch (cmd) {
6197 case IPC_INFO:
6198 case SEM_INFO:
6199 /* No specific object, just general system-wide information. */
6200 return avc_has_perm(&selinux_state,
6201 current_sid(), SECINITSID_KERNEL,
6202 SECCLASS_SYSTEM, SYSTEM__IPC_INFO, NULL);
6203 case GETPID:
6204 case GETNCNT:
6205 case GETZCNT:
6206 perms = SEM__GETATTR;
6207 break;
6208 case GETVAL:
6209 case GETALL:
6210 perms = SEM__READ;
6211 break;
6212 case SETVAL:
6213 case SETALL:
6214 perms = SEM__WRITE;
6215 break;
6216 case IPC_RMID:
6217 perms = SEM__DESTROY;
6218 break;
6219 case IPC_SET:
6220 perms = SEM__SETATTR;
6221 break;
6222 case IPC_STAT:
6223 case SEM_STAT:
6224 case SEM_STAT_ANY:
6225 perms = SEM__GETATTR | SEM__ASSOCIATE;
6226 break;
6227 default:
6228 return 0;
6229 }
6230
6231 err = ipc_has_perm(sma, perms);
6232 return err;
6233}
6234
6235static int selinux_sem_semop(struct kern_ipc_perm *sma,
6236 struct sembuf *sops, unsigned nsops, int alter)
6237{
6238 u32 perms;
6239
6240 if (alter)
6241 perms = SEM__READ | SEM__WRITE;
6242 else
6243 perms = SEM__READ;
6244
6245 return ipc_has_perm(sma, perms);
6246}
6247
6248static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
6249{
6250 u32 av = 0;
6251
6252 av = 0;
6253 if (flag & S_IRUGO)
6254 av |= IPC__UNIX_READ;
6255 if (flag & S_IWUGO)
6256 av |= IPC__UNIX_WRITE;
6257
6258 if (av == 0)
6259 return 0;
6260
6261 return ipc_has_perm(ipcp, av);
6262}
6263
6264static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
6265{
6266 struct ipc_security_struct *isec = selinux_ipc(ipcp);
6267 *secid = isec->sid;
6268}
6269
6270static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
6271{
6272 if (inode)
6273 inode_doinit_with_dentry(inode, dentry);
6274}
6275
6276static int selinux_getprocattr(struct task_struct *p,
6277 char *name, char **value)
6278{
6279 const struct task_security_struct *__tsec;
6280 u32 sid;
6281 int error;
6282 unsigned len;
6283
6284 rcu_read_lock();
6285 __tsec = selinux_cred(__task_cred(p));
6286
6287 if (current != p) {
6288 error = avc_has_perm(&selinux_state,
6289 current_sid(), __tsec->sid,
6290 SECCLASS_PROCESS, PROCESS__GETATTR, NULL);
6291 if (error)
6292 goto bad;
6293 }
6294
6295 if (!strcmp(name, "current"))
6296 sid = __tsec->sid;
6297 else if (!strcmp(name, "prev"))
6298 sid = __tsec->osid;
6299 else if (!strcmp(name, "exec"))
6300 sid = __tsec->exec_sid;
6301 else if (!strcmp(name, "fscreate"))
6302 sid = __tsec->create_sid;
6303 else if (!strcmp(name, "keycreate"))
6304 sid = __tsec->keycreate_sid;
6305 else if (!strcmp(name, "sockcreate"))
6306 sid = __tsec->sockcreate_sid;
6307 else {
6308 error = -EINVAL;
6309 goto bad;
6310 }
6311 rcu_read_unlock();
6312
6313 if (!sid)
6314 return 0;
6315
6316 error = security_sid_to_context(&selinux_state, sid, value, &len);
6317 if (error)
6318 return error;
6319 return len;
6320
6321bad:
6322 rcu_read_unlock();
6323 return error;
6324}
6325
6326static int selinux_setprocattr(const char *name, void *value, size_t size)
6327{
6328 struct task_security_struct *tsec;
6329 struct cred *new;
6330 u32 mysid = current_sid(), sid = 0, ptsid;
6331 int error;
6332 char *str = value;
6333
6334 /*
6335 * Basic control over ability to set these attributes at all.
6336 */
6337 if (!strcmp(name, "exec"))
6338 error = avc_has_perm(&selinux_state,
6339 mysid, mysid, SECCLASS_PROCESS,
6340 PROCESS__SETEXEC, NULL);
6341 else if (!strcmp(name, "fscreate"))
6342 error = avc_has_perm(&selinux_state,
6343 mysid, mysid, SECCLASS_PROCESS,
6344 PROCESS__SETFSCREATE, NULL);
6345 else if (!strcmp(name, "keycreate"))
6346 error = avc_has_perm(&selinux_state,
6347 mysid, mysid, SECCLASS_PROCESS,
6348 PROCESS__SETKEYCREATE, NULL);
6349 else if (!strcmp(name, "sockcreate"))
6350 error = avc_has_perm(&selinux_state,
6351 mysid, mysid, SECCLASS_PROCESS,
6352 PROCESS__SETSOCKCREATE, NULL);
6353 else if (!strcmp(name, "current"))
6354 error = avc_has_perm(&selinux_state,
6355 mysid, mysid, SECCLASS_PROCESS,
6356 PROCESS__SETCURRENT, NULL);
6357 else
6358 error = -EINVAL;
6359 if (error)
6360 return error;
6361
6362 /* Obtain a SID for the context, if one was specified. */
6363 if (size && str[0] && str[0] != '\n') {
6364 if (str[size-1] == '\n') {
6365 str[size-1] = 0;
6366 size--;
6367 }
6368 error = security_context_to_sid(&selinux_state, value, size,
6369 &sid, GFP_KERNEL);
6370 if (error == -EINVAL && !strcmp(name, "fscreate")) {
6371 if (!has_cap_mac_admin(true)) {
6372 struct audit_buffer *ab;
6373 size_t audit_size;
6374
6375 /* We strip a nul only if it is at the end, otherwise the
6376 * context contains a nul and we should audit that */
6377 if (str[size - 1] == '\0')
6378 audit_size = size - 1;
6379 else
6380 audit_size = size;
6381 ab = audit_log_start(audit_context(),
6382 GFP_ATOMIC,
6383 AUDIT_SELINUX_ERR);
6384 audit_log_format(ab, "op=fscreate invalid_context=");
6385 audit_log_n_untrustedstring(ab, value, audit_size);
6386 audit_log_end(ab);
6387
6388 return error;
6389 }
6390 error = security_context_to_sid_force(
6391 &selinux_state,
6392 value, size, &sid);
6393 }
6394 if (error)
6395 return error;
6396 }
6397
6398 new = prepare_creds();
6399 if (!new)
6400 return -ENOMEM;
6401
6402 /* Permission checking based on the specified context is
6403 performed during the actual operation (execve,
6404 open/mkdir/...), when we know the full context of the
6405 operation. See selinux_bprm_creds_for_exec for the execve
6406 checks and may_create for the file creation checks. The
6407 operation will then fail if the context is not permitted. */
6408 tsec = selinux_cred(new);
6409 if (!strcmp(name, "exec")) {
6410 tsec->exec_sid = sid;
6411 } else if (!strcmp(name, "fscreate")) {
6412 tsec->create_sid = sid;
6413 } else if (!strcmp(name, "keycreate")) {
6414 if (sid) {
6415 error = avc_has_perm(&selinux_state, mysid, sid,
6416 SECCLASS_KEY, KEY__CREATE, NULL);
6417 if (error)
6418 goto abort_change;
6419 }
6420 tsec->keycreate_sid = sid;
6421 } else if (!strcmp(name, "sockcreate")) {
6422 tsec->sockcreate_sid = sid;
6423 } else if (!strcmp(name, "current")) {
6424 error = -EINVAL;
6425 if (sid == 0)
6426 goto abort_change;
6427
6428 /* Only allow single threaded processes to change context */
6429 error = -EPERM;
6430 if (!current_is_single_threaded()) {
6431 error = security_bounded_transition(&selinux_state,
6432 tsec->sid, sid);
6433 if (error)
6434 goto abort_change;
6435 }
6436
6437 /* Check permissions for the transition. */
6438 error = avc_has_perm(&selinux_state,
6439 tsec->sid, sid, SECCLASS_PROCESS,
6440 PROCESS__DYNTRANSITION, NULL);
6441 if (error)
6442 goto abort_change;
6443
6444 /* Check for ptracing, and update the task SID if ok.
6445 Otherwise, leave SID unchanged and fail. */
6446 ptsid = ptrace_parent_sid();
6447 if (ptsid != 0) {
6448 error = avc_has_perm(&selinux_state,
6449 ptsid, sid, SECCLASS_PROCESS,
6450 PROCESS__PTRACE, NULL);
6451 if (error)
6452 goto abort_change;
6453 }
6454
6455 tsec->sid = sid;
6456 } else {
6457 error = -EINVAL;
6458 goto abort_change;
6459 }
6460
6461 commit_creds(new);
6462 return size;
6463
6464abort_change:
6465 abort_creds(new);
6466 return error;
6467}
6468
6469static int selinux_ismaclabel(const char *name)
6470{
6471 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
6472}
6473
6474static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
6475{
6476 return security_sid_to_context(&selinux_state, secid,
6477 secdata, seclen);
6478}
6479
6480static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
6481{
6482 return security_context_to_sid(&selinux_state, secdata, seclen,
6483 secid, GFP_KERNEL);
6484}
6485
6486static void selinux_release_secctx(char *secdata, u32 seclen)
6487{
6488 kfree(secdata);
6489}
6490
6491static void selinux_inode_invalidate_secctx(struct inode *inode)
6492{
6493 struct inode_security_struct *isec = selinux_inode(inode);
6494
6495 spin_lock(&isec->lock);
6496 isec->initialized = LABEL_INVALID;
6497 spin_unlock(&isec->lock);
6498}
6499
6500/*
6501 * called with inode->i_mutex locked
6502 */
6503static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6504{
6505 int rc = selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX,
6506 ctx, ctxlen, 0);
6507 /* Do not return error when suppressing label (SBLABEL_MNT not set). */
6508 return rc == -EOPNOTSUPP ? 0 : rc;
6509}
6510
6511/*
6512 * called with inode->i_mutex locked
6513 */
6514static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6515{
6516 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6517}
6518
6519static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6520{
6521 int len = 0;
6522 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6523 ctx, true);
6524 if (len < 0)
6525 return len;
6526 *ctxlen = len;
6527 return 0;
6528}
6529#ifdef CONFIG_KEYS
6530
6531static int selinux_key_alloc(struct key *k, const struct cred *cred,
6532 unsigned long flags)
6533{
6534 const struct task_security_struct *tsec;
6535 struct key_security_struct *ksec;
6536
6537 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6538 if (!ksec)
6539 return -ENOMEM;
6540
6541 tsec = selinux_cred(cred);
6542 if (tsec->keycreate_sid)
6543 ksec->sid = tsec->keycreate_sid;
6544 else
6545 ksec->sid = tsec->sid;
6546
6547 k->security = ksec;
6548 return 0;
6549}
6550
6551static void selinux_key_free(struct key *k)
6552{
6553 struct key_security_struct *ksec = k->security;
6554
6555 k->security = NULL;
6556 kfree(ksec);
6557}
6558
6559static int selinux_key_permission(key_ref_t key_ref,
6560 const struct cred *cred,
6561 enum key_need_perm need_perm)
6562{
6563 struct key *key;
6564 struct key_security_struct *ksec;
6565 u32 perm, sid;
6566
6567 switch (need_perm) {
6568 case KEY_NEED_VIEW:
6569 perm = KEY__VIEW;
6570 break;
6571 case KEY_NEED_READ:
6572 perm = KEY__READ;
6573 break;
6574 case KEY_NEED_WRITE:
6575 perm = KEY__WRITE;
6576 break;
6577 case KEY_NEED_SEARCH:
6578 perm = KEY__SEARCH;
6579 break;
6580 case KEY_NEED_LINK:
6581 perm = KEY__LINK;
6582 break;
6583 case KEY_NEED_SETATTR:
6584 perm = KEY__SETATTR;
6585 break;
6586 case KEY_NEED_UNLINK:
6587 case KEY_SYSADMIN_OVERRIDE:
6588 case KEY_AUTHTOKEN_OVERRIDE:
6589 case KEY_DEFER_PERM_CHECK:
6590 return 0;
6591 default:
6592 WARN_ON(1);
6593 return -EPERM;
6594
6595 }
6596
6597 sid = cred_sid(cred);
6598 key = key_ref_to_ptr(key_ref);
6599 ksec = key->security;
6600
6601 return avc_has_perm(&selinux_state,
6602 sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6603}
6604
6605static int selinux_key_getsecurity(struct key *key, char **_buffer)
6606{
6607 struct key_security_struct *ksec = key->security;
6608 char *context = NULL;
6609 unsigned len;
6610 int rc;
6611
6612 rc = security_sid_to_context(&selinux_state, ksec->sid,
6613 &context, &len);
6614 if (!rc)
6615 rc = len;
6616 *_buffer = context;
6617 return rc;
6618}
6619
6620#ifdef CONFIG_KEY_NOTIFICATIONS
6621static int selinux_watch_key(struct key *key)
6622{
6623 struct key_security_struct *ksec = key->security;
6624 u32 sid = current_sid();
6625
6626 return avc_has_perm(&selinux_state,
6627 sid, ksec->sid, SECCLASS_KEY, KEY__VIEW, NULL);
6628}
6629#endif
6630#endif
6631
6632#ifdef CONFIG_SECURITY_INFINIBAND
6633static int selinux_ib_pkey_access(void *ib_sec, u64 subnet_prefix, u16 pkey_val)
6634{
6635 struct common_audit_data ad;
6636 int err;
6637 u32 sid = 0;
6638 struct ib_security_struct *sec = ib_sec;
6639 struct lsm_ibpkey_audit ibpkey;
6640
6641 err = sel_ib_pkey_sid(subnet_prefix, pkey_val, &sid);
6642 if (err)
6643 return err;
6644
6645 ad.type = LSM_AUDIT_DATA_IBPKEY;
6646 ibpkey.subnet_prefix = subnet_prefix;
6647 ibpkey.pkey = pkey_val;
6648 ad.u.ibpkey = &ibpkey;
6649 return avc_has_perm(&selinux_state,
6650 sec->sid, sid,
6651 SECCLASS_INFINIBAND_PKEY,
6652 INFINIBAND_PKEY__ACCESS, &ad);
6653}
6654
6655static int selinux_ib_endport_manage_subnet(void *ib_sec, const char *dev_name,
6656 u8 port_num)
6657{
6658 struct common_audit_data ad;
6659 int err;
6660 u32 sid = 0;
6661 struct ib_security_struct *sec = ib_sec;
6662 struct lsm_ibendport_audit ibendport;
6663
6664 err = security_ib_endport_sid(&selinux_state, dev_name, port_num,
6665 &sid);
6666
6667 if (err)
6668 return err;
6669
6670 ad.type = LSM_AUDIT_DATA_IBENDPORT;
6671 strncpy(ibendport.dev_name, dev_name, sizeof(ibendport.dev_name));
6672 ibendport.port = port_num;
6673 ad.u.ibendport = &ibendport;
6674 return avc_has_perm(&selinux_state,
6675 sec->sid, sid,
6676 SECCLASS_INFINIBAND_ENDPORT,
6677 INFINIBAND_ENDPORT__MANAGE_SUBNET, &ad);
6678}
6679
6680static int selinux_ib_alloc_security(void **ib_sec)
6681{
6682 struct ib_security_struct *sec;
6683
6684 sec = kzalloc(sizeof(*sec), GFP_KERNEL);
6685 if (!sec)
6686 return -ENOMEM;
6687 sec->sid = current_sid();
6688
6689 *ib_sec = sec;
6690 return 0;
6691}
6692
6693static void selinux_ib_free_security(void *ib_sec)
6694{
6695 kfree(ib_sec);
6696}
6697#endif
6698
6699#ifdef CONFIG_BPF_SYSCALL
6700static int selinux_bpf(int cmd, union bpf_attr *attr,
6701 unsigned int size)
6702{
6703 u32 sid = current_sid();
6704 int ret;
6705
6706 switch (cmd) {
6707 case BPF_MAP_CREATE:
6708 ret = avc_has_perm(&selinux_state,
6709 sid, sid, SECCLASS_BPF, BPF__MAP_CREATE,
6710 NULL);
6711 break;
6712 case BPF_PROG_LOAD:
6713 ret = avc_has_perm(&selinux_state,
6714 sid, sid, SECCLASS_BPF, BPF__PROG_LOAD,
6715 NULL);
6716 break;
6717 default:
6718 ret = 0;
6719 break;
6720 }
6721
6722 return ret;
6723}
6724
6725static u32 bpf_map_fmode_to_av(fmode_t fmode)
6726{
6727 u32 av = 0;
6728
6729 if (fmode & FMODE_READ)
6730 av |= BPF__MAP_READ;
6731 if (fmode & FMODE_WRITE)
6732 av |= BPF__MAP_WRITE;
6733 return av;
6734}
6735
6736/* This function will check the file pass through unix socket or binder to see
6737 * if it is a bpf related object. And apply correspinding checks on the bpf
6738 * object based on the type. The bpf maps and programs, not like other files and
6739 * socket, are using a shared anonymous inode inside the kernel as their inode.
6740 * So checking that inode cannot identify if the process have privilege to
6741 * access the bpf object and that's why we have to add this additional check in
6742 * selinux_file_receive and selinux_binder_transfer_files.
6743 */
6744static int bpf_fd_pass(struct file *file, u32 sid)
6745{
6746 struct bpf_security_struct *bpfsec;
6747 struct bpf_prog *prog;
6748 struct bpf_map *map;
6749 int ret;
6750
6751 if (file->f_op == &bpf_map_fops) {
6752 map = file->private_data;
6753 bpfsec = map->security;
6754 ret = avc_has_perm(&selinux_state,
6755 sid, bpfsec->sid, SECCLASS_BPF,
6756 bpf_map_fmode_to_av(file->f_mode), NULL);
6757 if (ret)
6758 return ret;
6759 } else if (file->f_op == &bpf_prog_fops) {
6760 prog = file->private_data;
6761 bpfsec = prog->aux->security;
6762 ret = avc_has_perm(&selinux_state,
6763 sid, bpfsec->sid, SECCLASS_BPF,
6764 BPF__PROG_RUN, NULL);
6765 if (ret)
6766 return ret;
6767 }
6768 return 0;
6769}
6770
6771static int selinux_bpf_map(struct bpf_map *map, fmode_t fmode)
6772{
6773 u32 sid = current_sid();
6774 struct bpf_security_struct *bpfsec;
6775
6776 bpfsec = map->security;
6777 return avc_has_perm(&selinux_state,
6778 sid, bpfsec->sid, SECCLASS_BPF,
6779 bpf_map_fmode_to_av(fmode), NULL);
6780}
6781
6782static int selinux_bpf_prog(struct bpf_prog *prog)
6783{
6784 u32 sid = current_sid();
6785 struct bpf_security_struct *bpfsec;
6786
6787 bpfsec = prog->aux->security;
6788 return avc_has_perm(&selinux_state,
6789 sid, bpfsec->sid, SECCLASS_BPF,
6790 BPF__PROG_RUN, NULL);
6791}
6792
6793static int selinux_bpf_map_alloc(struct bpf_map *map)
6794{
6795 struct bpf_security_struct *bpfsec;
6796
6797 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6798 if (!bpfsec)
6799 return -ENOMEM;
6800
6801 bpfsec->sid = current_sid();
6802 map->security = bpfsec;
6803
6804 return 0;
6805}
6806
6807static void selinux_bpf_map_free(struct bpf_map *map)
6808{
6809 struct bpf_security_struct *bpfsec = map->security;
6810
6811 map->security = NULL;
6812 kfree(bpfsec);
6813}
6814
6815static int selinux_bpf_prog_alloc(struct bpf_prog_aux *aux)
6816{
6817 struct bpf_security_struct *bpfsec;
6818
6819 bpfsec = kzalloc(sizeof(*bpfsec), GFP_KERNEL);
6820 if (!bpfsec)
6821 return -ENOMEM;
6822
6823 bpfsec->sid = current_sid();
6824 aux->security = bpfsec;
6825
6826 return 0;
6827}
6828
6829static void selinux_bpf_prog_free(struct bpf_prog_aux *aux)
6830{
6831 struct bpf_security_struct *bpfsec = aux->security;
6832
6833 aux->security = NULL;
6834 kfree(bpfsec);
6835}
6836#endif
6837
6838static int selinux_lockdown(enum lockdown_reason what)
6839{
6840 struct common_audit_data ad;
6841 u32 sid = current_sid();
6842 int invalid_reason = (what <= LOCKDOWN_NONE) ||
6843 (what == LOCKDOWN_INTEGRITY_MAX) ||
6844 (what >= LOCKDOWN_CONFIDENTIALITY_MAX);
6845
6846 if (WARN(invalid_reason, "Invalid lockdown reason")) {
6847 audit_log(audit_context(),
6848 GFP_ATOMIC, AUDIT_SELINUX_ERR,
6849 "lockdown_reason=invalid");
6850 return -EINVAL;
6851 }
6852
6853 ad.type = LSM_AUDIT_DATA_LOCKDOWN;
6854 ad.u.reason = what;
6855
6856 if (what <= LOCKDOWN_INTEGRITY_MAX)
6857 return avc_has_perm(&selinux_state,
6858 sid, sid, SECCLASS_LOCKDOWN,
6859 LOCKDOWN__INTEGRITY, &ad);
6860 else
6861 return avc_has_perm(&selinux_state,
6862 sid, sid, SECCLASS_LOCKDOWN,
6863 LOCKDOWN__CONFIDENTIALITY, &ad);
6864}
6865
6866struct lsm_blob_sizes selinux_blob_sizes __lsm_ro_after_init = {
6867 .lbs_cred = sizeof(struct task_security_struct),
6868 .lbs_file = sizeof(struct file_security_struct),
6869 .lbs_inode = sizeof(struct inode_security_struct),
6870 .lbs_ipc = sizeof(struct ipc_security_struct),
6871 .lbs_msg_msg = sizeof(struct msg_security_struct),
6872};
6873
6874#ifdef CONFIG_PERF_EVENTS
6875static int selinux_perf_event_open(struct perf_event_attr *attr, int type)
6876{
6877 u32 requested, sid = current_sid();
6878
6879 if (type == PERF_SECURITY_OPEN)
6880 requested = PERF_EVENT__OPEN;
6881 else if (type == PERF_SECURITY_CPU)
6882 requested = PERF_EVENT__CPU;
6883 else if (type == PERF_SECURITY_KERNEL)
6884 requested = PERF_EVENT__KERNEL;
6885 else if (type == PERF_SECURITY_TRACEPOINT)
6886 requested = PERF_EVENT__TRACEPOINT;
6887 else
6888 return -EINVAL;
6889
6890 return avc_has_perm(&selinux_state, sid, sid, SECCLASS_PERF_EVENT,
6891 requested, NULL);
6892}
6893
6894static int selinux_perf_event_alloc(struct perf_event *event)
6895{
6896 struct perf_event_security_struct *perfsec;
6897
6898 perfsec = kzalloc(sizeof(*perfsec), GFP_KERNEL);
6899 if (!perfsec)
6900 return -ENOMEM;
6901
6902 perfsec->sid = current_sid();
6903 event->security = perfsec;
6904
6905 return 0;
6906}
6907
6908static void selinux_perf_event_free(struct perf_event *event)
6909{
6910 struct perf_event_security_struct *perfsec = event->security;
6911
6912 event->security = NULL;
6913 kfree(perfsec);
6914}
6915
6916static int selinux_perf_event_read(struct perf_event *event)
6917{
6918 struct perf_event_security_struct *perfsec = event->security;
6919 u32 sid = current_sid();
6920
6921 return avc_has_perm(&selinux_state, sid, perfsec->sid,
6922 SECCLASS_PERF_EVENT, PERF_EVENT__READ, NULL);
6923}
6924
6925static int selinux_perf_event_write(struct perf_event *event)
6926{
6927 struct perf_event_security_struct *perfsec = event->security;
6928 u32 sid = current_sid();
6929
6930 return avc_has_perm(&selinux_state, sid, perfsec->sid,
6931 SECCLASS_PERF_EVENT, PERF_EVENT__WRITE, NULL);
6932}
6933#endif
6934
6935/*
6936 * IMPORTANT NOTE: When adding new hooks, please be careful to keep this order:
6937 * 1. any hooks that don't belong to (2.) or (3.) below,
6938 * 2. hooks that both access structures allocated by other hooks, and allocate
6939 * structures that can be later accessed by other hooks (mostly "cloning"
6940 * hooks),
6941 * 3. hooks that only allocate structures that can be later accessed by other
6942 * hooks ("allocating" hooks).
6943 *
6944 * Please follow block comment delimiters in the list to keep this order.
6945 *
6946 * This ordering is needed for SELinux runtime disable to work at least somewhat
6947 * safely. Breaking the ordering rules above might lead to NULL pointer derefs
6948 * when disabling SELinux at runtime.
6949 */
6950static struct security_hook_list selinux_hooks[] __lsm_ro_after_init = {
6951 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6952 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6953 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6954 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6955
6956 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6957 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6958 LSM_HOOK_INIT(capget, selinux_capget),
6959 LSM_HOOK_INIT(capset, selinux_capset),
6960 LSM_HOOK_INIT(capable, selinux_capable),
6961 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6962 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6963 LSM_HOOK_INIT(syslog, selinux_syslog),
6964 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6965
6966 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6967
6968 LSM_HOOK_INIT(bprm_creds_for_exec, selinux_bprm_creds_for_exec),
6969 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6970 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6971
6972 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6973 LSM_HOOK_INIT(sb_free_mnt_opts, selinux_free_mnt_opts),
6974 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6975 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6976 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6977 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6978 LSM_HOOK_INIT(sb_mount, selinux_mount),
6979 LSM_HOOK_INIT(sb_umount, selinux_umount),
6980 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6981 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6982
6983 LSM_HOOK_INIT(move_mount, selinux_move_mount),
6984
6985 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6986 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6987
6988 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6989 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6990 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6991 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6992 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6993 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6994 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6995 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6996 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6997 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6998 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6999 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
7000 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
7001 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
7002 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
7003 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
7004 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
7005 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
7006 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
7007 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
7008 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
7009 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
7010 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
7011 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
7012 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
7013 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
7014 LSM_HOOK_INIT(path_notify, selinux_path_notify),
7015
7016 LSM_HOOK_INIT(kernfs_init_security, selinux_kernfs_init_security),
7017
7018 LSM_HOOK_INIT(file_permission, selinux_file_permission),
7019 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
7020 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
7021 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
7022 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
7023 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
7024 LSM_HOOK_INIT(file_lock, selinux_file_lock),
7025 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
7026 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
7027 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
7028 LSM_HOOK_INIT(file_receive, selinux_file_receive),
7029
7030 LSM_HOOK_INIT(file_open, selinux_file_open),
7031
7032 LSM_HOOK_INIT(task_alloc, selinux_task_alloc),
7033 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
7034 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
7035 LSM_HOOK_INIT(cred_getsecid, selinux_cred_getsecid),
7036 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
7037 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
7038 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
7039 LSM_HOOK_INIT(kernel_load_data, selinux_kernel_load_data),
7040 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
7041 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
7042 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
7043 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
7044 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
7045 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
7046 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
7047 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
7048 LSM_HOOK_INIT(task_prlimit, selinux_task_prlimit),
7049 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
7050 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
7051 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
7052 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
7053 LSM_HOOK_INIT(task_kill, selinux_task_kill),
7054 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
7055
7056 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
7057 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
7058
7059 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
7060 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
7061 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
7062 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
7063
7064 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
7065 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
7066 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
7067
7068 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
7069 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
7070 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
7071
7072 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
7073
7074 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
7075 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
7076
7077 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
7078 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
7079 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
7080 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
7081 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
7082 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
7083
7084 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
7085 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
7086
7087 LSM_HOOK_INIT(socket_create, selinux_socket_create),
7088 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
7089 LSM_HOOK_INIT(socket_socketpair, selinux_socket_socketpair),
7090 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
7091 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
7092 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
7093 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
7094 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
7095 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
7096 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
7097 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
7098 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
7099 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
7100 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
7101 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
7102 LSM_HOOK_INIT(socket_getpeersec_stream,
7103 selinux_socket_getpeersec_stream),
7104 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
7105 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
7106 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
7107 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
7108 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
7109 LSM_HOOK_INIT(sctp_assoc_request, selinux_sctp_assoc_request),
7110 LSM_HOOK_INIT(sctp_sk_clone, selinux_sctp_sk_clone),
7111 LSM_HOOK_INIT(sctp_bind_connect, selinux_sctp_bind_connect),
7112 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
7113 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
7114 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
7115 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
7116 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
7117 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
7118 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
7119 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
7120 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
7121 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
7122 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
7123 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
7124#ifdef CONFIG_SECURITY_INFINIBAND
7125 LSM_HOOK_INIT(ib_pkey_access, selinux_ib_pkey_access),
7126 LSM_HOOK_INIT(ib_endport_manage_subnet,
7127 selinux_ib_endport_manage_subnet),
7128 LSM_HOOK_INIT(ib_free_security, selinux_ib_free_security),
7129#endif
7130#ifdef CONFIG_SECURITY_NETWORK_XFRM
7131 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
7132 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
7133 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
7134 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
7135 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
7136 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
7137 selinux_xfrm_state_pol_flow_match),
7138 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
7139#endif
7140
7141#ifdef CONFIG_KEYS
7142 LSM_HOOK_INIT(key_free, selinux_key_free),
7143 LSM_HOOK_INIT(key_permission, selinux_key_permission),
7144 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
7145#ifdef CONFIG_KEY_NOTIFICATIONS
7146 LSM_HOOK_INIT(watch_key, selinux_watch_key),
7147#endif
7148#endif
7149
7150#ifdef CONFIG_AUDIT
7151 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
7152 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
7153 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
7154#endif
7155
7156#ifdef CONFIG_BPF_SYSCALL
7157 LSM_HOOK_INIT(bpf, selinux_bpf),
7158 LSM_HOOK_INIT(bpf_map, selinux_bpf_map),
7159 LSM_HOOK_INIT(bpf_prog, selinux_bpf_prog),
7160 LSM_HOOK_INIT(bpf_map_free_security, selinux_bpf_map_free),
7161 LSM_HOOK_INIT(bpf_prog_free_security, selinux_bpf_prog_free),
7162#endif
7163
7164#ifdef CONFIG_PERF_EVENTS
7165 LSM_HOOK_INIT(perf_event_open, selinux_perf_event_open),
7166 LSM_HOOK_INIT(perf_event_free, selinux_perf_event_free),
7167 LSM_HOOK_INIT(perf_event_read, selinux_perf_event_read),
7168 LSM_HOOK_INIT(perf_event_write, selinux_perf_event_write),
7169#endif
7170
7171 LSM_HOOK_INIT(locked_down, selinux_lockdown),
7172
7173 /*
7174 * PUT "CLONING" (ACCESSING + ALLOCATING) HOOKS HERE
7175 */
7176 LSM_HOOK_INIT(fs_context_dup, selinux_fs_context_dup),
7177 LSM_HOOK_INIT(fs_context_parse_param, selinux_fs_context_parse_param),
7178 LSM_HOOK_INIT(sb_eat_lsm_opts, selinux_sb_eat_lsm_opts),
7179 LSM_HOOK_INIT(sb_add_mnt_opt, selinux_add_mnt_opt),
7180#ifdef CONFIG_SECURITY_NETWORK_XFRM
7181 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
7182#endif
7183
7184 /*
7185 * PUT "ALLOCATING" HOOKS HERE
7186 */
7187 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
7188 LSM_HOOK_INIT(msg_queue_alloc_security,
7189 selinux_msg_queue_alloc_security),
7190 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
7191 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
7192 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
7193 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
7194 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
7195 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
7196 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
7197 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
7198#ifdef CONFIG_SECURITY_INFINIBAND
7199 LSM_HOOK_INIT(ib_alloc_security, selinux_ib_alloc_security),
7200#endif
7201#ifdef CONFIG_SECURITY_NETWORK_XFRM
7202 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
7203 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
7204 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
7205 selinux_xfrm_state_alloc_acquire),
7206#endif
7207#ifdef CONFIG_KEYS
7208 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
7209#endif
7210#ifdef CONFIG_AUDIT
7211 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
7212#endif
7213#ifdef CONFIG_BPF_SYSCALL
7214 LSM_HOOK_INIT(bpf_map_alloc_security, selinux_bpf_map_alloc),
7215 LSM_HOOK_INIT(bpf_prog_alloc_security, selinux_bpf_prog_alloc),
7216#endif
7217#ifdef CONFIG_PERF_EVENTS
7218 LSM_HOOK_INIT(perf_event_alloc, selinux_perf_event_alloc),
7219#endif
7220};
7221
7222static __init int selinux_init(void)
7223{
7224 pr_info("SELinux: Initializing.\n");
7225
7226 memset(&selinux_state, 0, sizeof(selinux_state));
7227 enforcing_set(&selinux_state, selinux_enforcing_boot);
7228 selinux_state.checkreqprot = selinux_checkreqprot_boot;
7229 selinux_ss_init(&selinux_state.ss);
7230 selinux_avc_init(&selinux_state.avc);
7231 mutex_init(&selinux_state.status_lock);
7232
7233 /* Set the security state for the initial task. */
7234 cred_init_security();
7235
7236 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
7237
7238 avc_init();
7239
7240 avtab_cache_init();
7241
7242 ebitmap_cache_init();
7243
7244 hashtab_cache_init();
7245
7246 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks), "selinux");
7247
7248 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
7249 panic("SELinux: Unable to register AVC netcache callback\n");
7250
7251 if (avc_add_callback(selinux_lsm_notifier_avc_callback, AVC_CALLBACK_RESET))
7252 panic("SELinux: Unable to register AVC LSM notifier callback\n");
7253
7254 if (selinux_enforcing_boot)
7255 pr_debug("SELinux: Starting in enforcing mode\n");
7256 else
7257 pr_debug("SELinux: Starting in permissive mode\n");
7258
7259 fs_validate_description("selinux", selinux_fs_parameters);
7260
7261 return 0;
7262}
7263
7264static void delayed_superblock_init(struct super_block *sb, void *unused)
7265{
7266 selinux_set_mnt_opts(sb, NULL, 0, NULL);
7267}
7268
7269void selinux_complete_init(void)
7270{
7271 pr_debug("SELinux: Completing initialization.\n");
7272
7273 /* Set up any superblocks initialized prior to the policy load. */
7274 pr_debug("SELinux: Setting up existing superblocks.\n");
7275 iterate_supers(delayed_superblock_init, NULL);
7276}
7277
7278/* SELinux requires early initialization in order to label
7279 all processes and objects when they are created. */
7280DEFINE_LSM(selinux) = {
7281 .name = "selinux",
7282 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
7283 .enabled = &selinux_enabled_boot,
7284 .blobs = &selinux_blob_sizes,
7285 .init = selinux_init,
7286};
7287
7288#if defined(CONFIG_NETFILTER)
7289
7290static const struct nf_hook_ops selinux_nf_ops[] = {
7291 {
7292 .hook = selinux_ipv4_postroute,
7293 .pf = NFPROTO_IPV4,
7294 .hooknum = NF_INET_POST_ROUTING,
7295 .priority = NF_IP_PRI_SELINUX_LAST,
7296 },
7297 {
7298 .hook = selinux_ipv4_forward,
7299 .pf = NFPROTO_IPV4,
7300 .hooknum = NF_INET_FORWARD,
7301 .priority = NF_IP_PRI_SELINUX_FIRST,
7302 },
7303 {
7304 .hook = selinux_ipv4_output,
7305 .pf = NFPROTO_IPV4,
7306 .hooknum = NF_INET_LOCAL_OUT,
7307 .priority = NF_IP_PRI_SELINUX_FIRST,
7308 },
7309#if IS_ENABLED(CONFIG_IPV6)
7310 {
7311 .hook = selinux_ipv6_postroute,
7312 .pf = NFPROTO_IPV6,
7313 .hooknum = NF_INET_POST_ROUTING,
7314 .priority = NF_IP6_PRI_SELINUX_LAST,
7315 },
7316 {
7317 .hook = selinux_ipv6_forward,
7318 .pf = NFPROTO_IPV6,
7319 .hooknum = NF_INET_FORWARD,
7320 .priority = NF_IP6_PRI_SELINUX_FIRST,
7321 },
7322 {
7323 .hook = selinux_ipv6_output,
7324 .pf = NFPROTO_IPV6,
7325 .hooknum = NF_INET_LOCAL_OUT,
7326 .priority = NF_IP6_PRI_SELINUX_FIRST,
7327 },
7328#endif /* IPV6 */
7329};
7330
7331static int __net_init selinux_nf_register(struct net *net)
7332{
7333 return nf_register_net_hooks(net, selinux_nf_ops,
7334 ARRAY_SIZE(selinux_nf_ops));
7335}
7336
7337static void __net_exit selinux_nf_unregister(struct net *net)
7338{
7339 nf_unregister_net_hooks(net, selinux_nf_ops,
7340 ARRAY_SIZE(selinux_nf_ops));
7341}
7342
7343static struct pernet_operations selinux_net_ops = {
7344 .init = selinux_nf_register,
7345 .exit = selinux_nf_unregister,
7346};
7347
7348static int __init selinux_nf_ip_init(void)
7349{
7350 int err;
7351
7352 if (!selinux_enabled_boot)
7353 return 0;
7354
7355 pr_debug("SELinux: Registering netfilter hooks\n");
7356
7357 err = register_pernet_subsys(&selinux_net_ops);
7358 if (err)
7359 panic("SELinux: register_pernet_subsys: error %d\n", err);
7360
7361 return 0;
7362}
7363__initcall(selinux_nf_ip_init);
7364
7365#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7366static void selinux_nf_ip_exit(void)
7367{
7368 pr_debug("SELinux: Unregistering netfilter hooks\n");
7369
7370 unregister_pernet_subsys(&selinux_net_ops);
7371}
7372#endif
7373
7374#else /* CONFIG_NETFILTER */
7375
7376#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7377#define selinux_nf_ip_exit()
7378#endif
7379
7380#endif /* CONFIG_NETFILTER */
7381
7382#ifdef CONFIG_SECURITY_SELINUX_DISABLE
7383int selinux_disable(struct selinux_state *state)
7384{
7385 if (selinux_initialized(state)) {
7386 /* Not permitted after initial policy load. */
7387 return -EINVAL;
7388 }
7389
7390 if (selinux_disabled(state)) {
7391 /* Only do this once. */
7392 return -EINVAL;
7393 }
7394
7395 selinux_mark_disabled(state);
7396
7397 pr_info("SELinux: Disabled at runtime.\n");
7398
7399 /*
7400 * Unregister netfilter hooks.
7401 * Must be done before security_delete_hooks() to avoid breaking
7402 * runtime disable.
7403 */
7404 selinux_nf_ip_exit();
7405
7406 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
7407
7408 /* Try to destroy the avc node cache */
7409 avc_disable();
7410
7411 /* Unregister selinuxfs. */
7412 exit_sel_fs();
7413
7414 return 0;
7415}
7416#endif
1/*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26#include <linux/init.h>
27#include <linux/kd.h>
28#include <linux/kernel.h>
29#include <linux/tracehook.h>
30#include <linux/errno.h>
31#include <linux/sched.h>
32#include <linux/security.h>
33#include <linux/xattr.h>
34#include <linux/capability.h>
35#include <linux/unistd.h>
36#include <linux/mm.h>
37#include <linux/mman.h>
38#include <linux/slab.h>
39#include <linux/pagemap.h>
40#include <linux/proc_fs.h>
41#include <linux/swap.h>
42#include <linux/spinlock.h>
43#include <linux/syscalls.h>
44#include <linux/dcache.h>
45#include <linux/file.h>
46#include <linux/fdtable.h>
47#include <linux/namei.h>
48#include <linux/mount.h>
49#include <linux/netfilter_ipv4.h>
50#include <linux/netfilter_ipv6.h>
51#include <linux/tty.h>
52#include <net/icmp.h>
53#include <net/ip.h> /* for local_port_range[] */
54#include <net/sock.h>
55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56#include <net/inet_connection_sock.h>
57#include <net/net_namespace.h>
58#include <net/netlabel.h>
59#include <linux/uaccess.h>
60#include <asm/ioctls.h>
61#include <linux/atomic.h>
62#include <linux/bitops.h>
63#include <linux/interrupt.h>
64#include <linux/netdevice.h> /* for network interface checks */
65#include <net/netlink.h>
66#include <linux/tcp.h>
67#include <linux/udp.h>
68#include <linux/dccp.h>
69#include <linux/quota.h>
70#include <linux/un.h> /* for Unix socket types */
71#include <net/af_unix.h> /* for Unix socket types */
72#include <linux/parser.h>
73#include <linux/nfs_mount.h>
74#include <net/ipv6.h>
75#include <linux/hugetlb.h>
76#include <linux/personality.h>
77#include <linux/audit.h>
78#include <linux/string.h>
79#include <linux/selinux.h>
80#include <linux/mutex.h>
81#include <linux/posix-timers.h>
82#include <linux/syslog.h>
83#include <linux/user_namespace.h>
84#include <linux/export.h>
85#include <linux/msg.h>
86#include <linux/shm.h>
87
88#include "avc.h"
89#include "objsec.h"
90#include "netif.h"
91#include "netnode.h"
92#include "netport.h"
93#include "xfrm.h"
94#include "netlabel.h"
95#include "audit.h"
96#include "avc_ss.h"
97
98extern struct security_operations *security_ops;
99
100/* SECMARK reference count */
101static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
102
103#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
104int selinux_enforcing;
105
106static int __init enforcing_setup(char *str)
107{
108 unsigned long enforcing;
109 if (!kstrtoul(str, 0, &enforcing))
110 selinux_enforcing = enforcing ? 1 : 0;
111 return 1;
112}
113__setup("enforcing=", enforcing_setup);
114#endif
115
116#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
117int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
118
119static int __init selinux_enabled_setup(char *str)
120{
121 unsigned long enabled;
122 if (!kstrtoul(str, 0, &enabled))
123 selinux_enabled = enabled ? 1 : 0;
124 return 1;
125}
126__setup("selinux=", selinux_enabled_setup);
127#else
128int selinux_enabled = 1;
129#endif
130
131static struct kmem_cache *sel_inode_cache;
132
133/**
134 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
135 *
136 * Description:
137 * This function checks the SECMARK reference counter to see if any SECMARK
138 * targets are currently configured, if the reference counter is greater than
139 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
140 * enabled, false (0) if SECMARK is disabled. If the always_check_network
141 * policy capability is enabled, SECMARK is always considered enabled.
142 *
143 */
144static int selinux_secmark_enabled(void)
145{
146 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
147}
148
149/**
150 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
151 *
152 * Description:
153 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
154 * (1) if any are enabled or false (0) if neither are enabled. If the
155 * always_check_network policy capability is enabled, peer labeling
156 * is always considered enabled.
157 *
158 */
159static int selinux_peerlbl_enabled(void)
160{
161 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
162}
163
164/*
165 * initialise the security for the init task
166 */
167static void cred_init_security(void)
168{
169 struct cred *cred = (struct cred *) current->real_cred;
170 struct task_security_struct *tsec;
171
172 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
173 if (!tsec)
174 panic("SELinux: Failed to initialize initial task.\n");
175
176 tsec->osid = tsec->sid = SECINITSID_KERNEL;
177 cred->security = tsec;
178}
179
180/*
181 * get the security ID of a set of credentials
182 */
183static inline u32 cred_sid(const struct cred *cred)
184{
185 const struct task_security_struct *tsec;
186
187 tsec = cred->security;
188 return tsec->sid;
189}
190
191/*
192 * get the objective security ID of a task
193 */
194static inline u32 task_sid(const struct task_struct *task)
195{
196 u32 sid;
197
198 rcu_read_lock();
199 sid = cred_sid(__task_cred(task));
200 rcu_read_unlock();
201 return sid;
202}
203
204/*
205 * get the subjective security ID of the current task
206 */
207static inline u32 current_sid(void)
208{
209 const struct task_security_struct *tsec = current_security();
210
211 return tsec->sid;
212}
213
214/* Allocate and free functions for each kind of security blob. */
215
216static int inode_alloc_security(struct inode *inode)
217{
218 struct inode_security_struct *isec;
219 u32 sid = current_sid();
220
221 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
222 if (!isec)
223 return -ENOMEM;
224
225 mutex_init(&isec->lock);
226 INIT_LIST_HEAD(&isec->list);
227 isec->inode = inode;
228 isec->sid = SECINITSID_UNLABELED;
229 isec->sclass = SECCLASS_FILE;
230 isec->task_sid = sid;
231 inode->i_security = isec;
232
233 return 0;
234}
235
236static void inode_free_rcu(struct rcu_head *head)
237{
238 struct inode_security_struct *isec;
239
240 isec = container_of(head, struct inode_security_struct, rcu);
241 kmem_cache_free(sel_inode_cache, isec);
242}
243
244static void inode_free_security(struct inode *inode)
245{
246 struct inode_security_struct *isec = inode->i_security;
247 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
248
249 spin_lock(&sbsec->isec_lock);
250 if (!list_empty(&isec->list))
251 list_del_init(&isec->list);
252 spin_unlock(&sbsec->isec_lock);
253
254 /*
255 * The inode may still be referenced in a path walk and
256 * a call to selinux_inode_permission() can be made
257 * after inode_free_security() is called. Ideally, the VFS
258 * wouldn't do this, but fixing that is a much harder
259 * job. For now, simply free the i_security via RCU, and
260 * leave the current inode->i_security pointer intact.
261 * The inode will be freed after the RCU grace period too.
262 */
263 call_rcu(&isec->rcu, inode_free_rcu);
264}
265
266static int file_alloc_security(struct file *file)
267{
268 struct file_security_struct *fsec;
269 u32 sid = current_sid();
270
271 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
272 if (!fsec)
273 return -ENOMEM;
274
275 fsec->sid = sid;
276 fsec->fown_sid = sid;
277 file->f_security = fsec;
278
279 return 0;
280}
281
282static void file_free_security(struct file *file)
283{
284 struct file_security_struct *fsec = file->f_security;
285 file->f_security = NULL;
286 kfree(fsec);
287}
288
289static int superblock_alloc_security(struct super_block *sb)
290{
291 struct superblock_security_struct *sbsec;
292
293 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
294 if (!sbsec)
295 return -ENOMEM;
296
297 mutex_init(&sbsec->lock);
298 INIT_LIST_HEAD(&sbsec->isec_head);
299 spin_lock_init(&sbsec->isec_lock);
300 sbsec->sb = sb;
301 sbsec->sid = SECINITSID_UNLABELED;
302 sbsec->def_sid = SECINITSID_FILE;
303 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
304 sb->s_security = sbsec;
305
306 return 0;
307}
308
309static void superblock_free_security(struct super_block *sb)
310{
311 struct superblock_security_struct *sbsec = sb->s_security;
312 sb->s_security = NULL;
313 kfree(sbsec);
314}
315
316/* The file system's label must be initialized prior to use. */
317
318static const char *labeling_behaviors[7] = {
319 "uses xattr",
320 "uses transition SIDs",
321 "uses task SIDs",
322 "uses genfs_contexts",
323 "not configured for labeling",
324 "uses mountpoint labeling",
325 "uses native labeling",
326};
327
328static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
329
330static inline int inode_doinit(struct inode *inode)
331{
332 return inode_doinit_with_dentry(inode, NULL);
333}
334
335enum {
336 Opt_error = -1,
337 Opt_context = 1,
338 Opt_fscontext = 2,
339 Opt_defcontext = 3,
340 Opt_rootcontext = 4,
341 Opt_labelsupport = 5,
342 Opt_nextmntopt = 6,
343};
344
345#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
346
347static const match_table_t tokens = {
348 {Opt_context, CONTEXT_STR "%s"},
349 {Opt_fscontext, FSCONTEXT_STR "%s"},
350 {Opt_defcontext, DEFCONTEXT_STR "%s"},
351 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
352 {Opt_labelsupport, LABELSUPP_STR},
353 {Opt_error, NULL},
354};
355
356#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
357
358static int may_context_mount_sb_relabel(u32 sid,
359 struct superblock_security_struct *sbsec,
360 const struct cred *cred)
361{
362 const struct task_security_struct *tsec = cred->security;
363 int rc;
364
365 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
366 FILESYSTEM__RELABELFROM, NULL);
367 if (rc)
368 return rc;
369
370 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
371 FILESYSTEM__RELABELTO, NULL);
372 return rc;
373}
374
375static int may_context_mount_inode_relabel(u32 sid,
376 struct superblock_security_struct *sbsec,
377 const struct cred *cred)
378{
379 const struct task_security_struct *tsec = cred->security;
380 int rc;
381 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
382 FILESYSTEM__RELABELFROM, NULL);
383 if (rc)
384 return rc;
385
386 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
387 FILESYSTEM__ASSOCIATE, NULL);
388 return rc;
389}
390
391static int selinux_is_sblabel_mnt(struct super_block *sb)
392{
393 struct superblock_security_struct *sbsec = sb->s_security;
394
395 if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
396 sbsec->behavior == SECURITY_FS_USE_TRANS ||
397 sbsec->behavior == SECURITY_FS_USE_TASK)
398 return 1;
399
400 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
401 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
402 return 1;
403
404 /*
405 * Special handling for rootfs. Is genfs but supports
406 * setting SELinux context on in-core inodes.
407 */
408 if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
409 return 1;
410
411 return 0;
412}
413
414static int sb_finish_set_opts(struct super_block *sb)
415{
416 struct superblock_security_struct *sbsec = sb->s_security;
417 struct dentry *root = sb->s_root;
418 struct inode *root_inode = root->d_inode;
419 int rc = 0;
420
421 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
422 /* Make sure that the xattr handler exists and that no
423 error other than -ENODATA is returned by getxattr on
424 the root directory. -ENODATA is ok, as this may be
425 the first boot of the SELinux kernel before we have
426 assigned xattr values to the filesystem. */
427 if (!root_inode->i_op->getxattr) {
428 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
429 "xattr support\n", sb->s_id, sb->s_type->name);
430 rc = -EOPNOTSUPP;
431 goto out;
432 }
433 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
434 if (rc < 0 && rc != -ENODATA) {
435 if (rc == -EOPNOTSUPP)
436 printk(KERN_WARNING "SELinux: (dev %s, type "
437 "%s) has no security xattr handler\n",
438 sb->s_id, sb->s_type->name);
439 else
440 printk(KERN_WARNING "SELinux: (dev %s, type "
441 "%s) getxattr errno %d\n", sb->s_id,
442 sb->s_type->name, -rc);
443 goto out;
444 }
445 }
446
447 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
448 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
449 sb->s_id, sb->s_type->name);
450 else
451 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
452 sb->s_id, sb->s_type->name,
453 labeling_behaviors[sbsec->behavior-1]);
454
455 sbsec->flags |= SE_SBINITIALIZED;
456 if (selinux_is_sblabel_mnt(sb))
457 sbsec->flags |= SBLABEL_MNT;
458
459 /* Initialize the root inode. */
460 rc = inode_doinit_with_dentry(root_inode, root);
461
462 /* Initialize any other inodes associated with the superblock, e.g.
463 inodes created prior to initial policy load or inodes created
464 during get_sb by a pseudo filesystem that directly
465 populates itself. */
466 spin_lock(&sbsec->isec_lock);
467next_inode:
468 if (!list_empty(&sbsec->isec_head)) {
469 struct inode_security_struct *isec =
470 list_entry(sbsec->isec_head.next,
471 struct inode_security_struct, list);
472 struct inode *inode = isec->inode;
473 spin_unlock(&sbsec->isec_lock);
474 inode = igrab(inode);
475 if (inode) {
476 if (!IS_PRIVATE(inode))
477 inode_doinit(inode);
478 iput(inode);
479 }
480 spin_lock(&sbsec->isec_lock);
481 list_del_init(&isec->list);
482 goto next_inode;
483 }
484 spin_unlock(&sbsec->isec_lock);
485out:
486 return rc;
487}
488
489/*
490 * This function should allow an FS to ask what it's mount security
491 * options were so it can use those later for submounts, displaying
492 * mount options, or whatever.
493 */
494static int selinux_get_mnt_opts(const struct super_block *sb,
495 struct security_mnt_opts *opts)
496{
497 int rc = 0, i;
498 struct superblock_security_struct *sbsec = sb->s_security;
499 char *context = NULL;
500 u32 len;
501 char tmp;
502
503 security_init_mnt_opts(opts);
504
505 if (!(sbsec->flags & SE_SBINITIALIZED))
506 return -EINVAL;
507
508 if (!ss_initialized)
509 return -EINVAL;
510
511 /* make sure we always check enough bits to cover the mask */
512 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
513
514 tmp = sbsec->flags & SE_MNTMASK;
515 /* count the number of mount options for this sb */
516 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
517 if (tmp & 0x01)
518 opts->num_mnt_opts++;
519 tmp >>= 1;
520 }
521 /* Check if the Label support flag is set */
522 if (sbsec->flags & SBLABEL_MNT)
523 opts->num_mnt_opts++;
524
525 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
526 if (!opts->mnt_opts) {
527 rc = -ENOMEM;
528 goto out_free;
529 }
530
531 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
532 if (!opts->mnt_opts_flags) {
533 rc = -ENOMEM;
534 goto out_free;
535 }
536
537 i = 0;
538 if (sbsec->flags & FSCONTEXT_MNT) {
539 rc = security_sid_to_context(sbsec->sid, &context, &len);
540 if (rc)
541 goto out_free;
542 opts->mnt_opts[i] = context;
543 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
544 }
545 if (sbsec->flags & CONTEXT_MNT) {
546 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
547 if (rc)
548 goto out_free;
549 opts->mnt_opts[i] = context;
550 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
551 }
552 if (sbsec->flags & DEFCONTEXT_MNT) {
553 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
554 if (rc)
555 goto out_free;
556 opts->mnt_opts[i] = context;
557 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
558 }
559 if (sbsec->flags & ROOTCONTEXT_MNT) {
560 struct inode *root = sbsec->sb->s_root->d_inode;
561 struct inode_security_struct *isec = root->i_security;
562
563 rc = security_sid_to_context(isec->sid, &context, &len);
564 if (rc)
565 goto out_free;
566 opts->mnt_opts[i] = context;
567 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
568 }
569 if (sbsec->flags & SBLABEL_MNT) {
570 opts->mnt_opts[i] = NULL;
571 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
572 }
573
574 BUG_ON(i != opts->num_mnt_opts);
575
576 return 0;
577
578out_free:
579 security_free_mnt_opts(opts);
580 return rc;
581}
582
583static int bad_option(struct superblock_security_struct *sbsec, char flag,
584 u32 old_sid, u32 new_sid)
585{
586 char mnt_flags = sbsec->flags & SE_MNTMASK;
587
588 /* check if the old mount command had the same options */
589 if (sbsec->flags & SE_SBINITIALIZED)
590 if (!(sbsec->flags & flag) ||
591 (old_sid != new_sid))
592 return 1;
593
594 /* check if we were passed the same options twice,
595 * aka someone passed context=a,context=b
596 */
597 if (!(sbsec->flags & SE_SBINITIALIZED))
598 if (mnt_flags & flag)
599 return 1;
600 return 0;
601}
602
603/*
604 * Allow filesystems with binary mount data to explicitly set mount point
605 * labeling information.
606 */
607static int selinux_set_mnt_opts(struct super_block *sb,
608 struct security_mnt_opts *opts,
609 unsigned long kern_flags,
610 unsigned long *set_kern_flags)
611{
612 const struct cred *cred = current_cred();
613 int rc = 0, i;
614 struct superblock_security_struct *sbsec = sb->s_security;
615 const char *name = sb->s_type->name;
616 struct inode *inode = sbsec->sb->s_root->d_inode;
617 struct inode_security_struct *root_isec = inode->i_security;
618 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
619 u32 defcontext_sid = 0;
620 char **mount_options = opts->mnt_opts;
621 int *flags = opts->mnt_opts_flags;
622 int num_opts = opts->num_mnt_opts;
623
624 mutex_lock(&sbsec->lock);
625
626 if (!ss_initialized) {
627 if (!num_opts) {
628 /* Defer initialization until selinux_complete_init,
629 after the initial policy is loaded and the security
630 server is ready to handle calls. */
631 goto out;
632 }
633 rc = -EINVAL;
634 printk(KERN_WARNING "SELinux: Unable to set superblock options "
635 "before the security server is initialized\n");
636 goto out;
637 }
638 if (kern_flags && !set_kern_flags) {
639 /* Specifying internal flags without providing a place to
640 * place the results is not allowed */
641 rc = -EINVAL;
642 goto out;
643 }
644
645 /*
646 * Binary mount data FS will come through this function twice. Once
647 * from an explicit call and once from the generic calls from the vfs.
648 * Since the generic VFS calls will not contain any security mount data
649 * we need to skip the double mount verification.
650 *
651 * This does open a hole in which we will not notice if the first
652 * mount using this sb set explict options and a second mount using
653 * this sb does not set any security options. (The first options
654 * will be used for both mounts)
655 */
656 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
657 && (num_opts == 0))
658 goto out;
659
660 /*
661 * parse the mount options, check if they are valid sids.
662 * also check if someone is trying to mount the same sb more
663 * than once with different security options.
664 */
665 for (i = 0; i < num_opts; i++) {
666 u32 sid;
667
668 if (flags[i] == SBLABEL_MNT)
669 continue;
670 rc = security_context_to_sid(mount_options[i],
671 strlen(mount_options[i]), &sid, GFP_KERNEL);
672 if (rc) {
673 printk(KERN_WARNING "SELinux: security_context_to_sid"
674 "(%s) failed for (dev %s, type %s) errno=%d\n",
675 mount_options[i], sb->s_id, name, rc);
676 goto out;
677 }
678 switch (flags[i]) {
679 case FSCONTEXT_MNT:
680 fscontext_sid = sid;
681
682 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
683 fscontext_sid))
684 goto out_double_mount;
685
686 sbsec->flags |= FSCONTEXT_MNT;
687 break;
688 case CONTEXT_MNT:
689 context_sid = sid;
690
691 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
692 context_sid))
693 goto out_double_mount;
694
695 sbsec->flags |= CONTEXT_MNT;
696 break;
697 case ROOTCONTEXT_MNT:
698 rootcontext_sid = sid;
699
700 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
701 rootcontext_sid))
702 goto out_double_mount;
703
704 sbsec->flags |= ROOTCONTEXT_MNT;
705
706 break;
707 case DEFCONTEXT_MNT:
708 defcontext_sid = sid;
709
710 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
711 defcontext_sid))
712 goto out_double_mount;
713
714 sbsec->flags |= DEFCONTEXT_MNT;
715
716 break;
717 default:
718 rc = -EINVAL;
719 goto out;
720 }
721 }
722
723 if (sbsec->flags & SE_SBINITIALIZED) {
724 /* previously mounted with options, but not on this attempt? */
725 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
726 goto out_double_mount;
727 rc = 0;
728 goto out;
729 }
730
731 if (strcmp(sb->s_type->name, "proc") == 0)
732 sbsec->flags |= SE_SBPROC;
733
734 if (!sbsec->behavior) {
735 /*
736 * Determine the labeling behavior to use for this
737 * filesystem type.
738 */
739 rc = security_fs_use(sb);
740 if (rc) {
741 printk(KERN_WARNING
742 "%s: security_fs_use(%s) returned %d\n",
743 __func__, sb->s_type->name, rc);
744 goto out;
745 }
746 }
747 /* sets the context of the superblock for the fs being mounted. */
748 if (fscontext_sid) {
749 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
750 if (rc)
751 goto out;
752
753 sbsec->sid = fscontext_sid;
754 }
755
756 /*
757 * Switch to using mount point labeling behavior.
758 * sets the label used on all file below the mountpoint, and will set
759 * the superblock context if not already set.
760 */
761 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
762 sbsec->behavior = SECURITY_FS_USE_NATIVE;
763 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
764 }
765
766 if (context_sid) {
767 if (!fscontext_sid) {
768 rc = may_context_mount_sb_relabel(context_sid, sbsec,
769 cred);
770 if (rc)
771 goto out;
772 sbsec->sid = context_sid;
773 } else {
774 rc = may_context_mount_inode_relabel(context_sid, sbsec,
775 cred);
776 if (rc)
777 goto out;
778 }
779 if (!rootcontext_sid)
780 rootcontext_sid = context_sid;
781
782 sbsec->mntpoint_sid = context_sid;
783 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
784 }
785
786 if (rootcontext_sid) {
787 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
788 cred);
789 if (rc)
790 goto out;
791
792 root_isec->sid = rootcontext_sid;
793 root_isec->initialized = 1;
794 }
795
796 if (defcontext_sid) {
797 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
798 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
799 rc = -EINVAL;
800 printk(KERN_WARNING "SELinux: defcontext option is "
801 "invalid for this filesystem type\n");
802 goto out;
803 }
804
805 if (defcontext_sid != sbsec->def_sid) {
806 rc = may_context_mount_inode_relabel(defcontext_sid,
807 sbsec, cred);
808 if (rc)
809 goto out;
810 }
811
812 sbsec->def_sid = defcontext_sid;
813 }
814
815 rc = sb_finish_set_opts(sb);
816out:
817 mutex_unlock(&sbsec->lock);
818 return rc;
819out_double_mount:
820 rc = -EINVAL;
821 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
822 "security settings for (dev %s, type %s)\n", sb->s_id, name);
823 goto out;
824}
825
826static int selinux_cmp_sb_context(const struct super_block *oldsb,
827 const struct super_block *newsb)
828{
829 struct superblock_security_struct *old = oldsb->s_security;
830 struct superblock_security_struct *new = newsb->s_security;
831 char oldflags = old->flags & SE_MNTMASK;
832 char newflags = new->flags & SE_MNTMASK;
833
834 if (oldflags != newflags)
835 goto mismatch;
836 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
837 goto mismatch;
838 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
839 goto mismatch;
840 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
841 goto mismatch;
842 if (oldflags & ROOTCONTEXT_MNT) {
843 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
844 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
845 if (oldroot->sid != newroot->sid)
846 goto mismatch;
847 }
848 return 0;
849mismatch:
850 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
851 "different security settings for (dev %s, "
852 "type %s)\n", newsb->s_id, newsb->s_type->name);
853 return -EBUSY;
854}
855
856static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
857 struct super_block *newsb)
858{
859 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
860 struct superblock_security_struct *newsbsec = newsb->s_security;
861
862 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
863 int set_context = (oldsbsec->flags & CONTEXT_MNT);
864 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
865
866 /*
867 * if the parent was able to be mounted it clearly had no special lsm
868 * mount options. thus we can safely deal with this superblock later
869 */
870 if (!ss_initialized)
871 return 0;
872
873 /* how can we clone if the old one wasn't set up?? */
874 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
875
876 /* if fs is reusing a sb, make sure that the contexts match */
877 if (newsbsec->flags & SE_SBINITIALIZED)
878 return selinux_cmp_sb_context(oldsb, newsb);
879
880 mutex_lock(&newsbsec->lock);
881
882 newsbsec->flags = oldsbsec->flags;
883
884 newsbsec->sid = oldsbsec->sid;
885 newsbsec->def_sid = oldsbsec->def_sid;
886 newsbsec->behavior = oldsbsec->behavior;
887
888 if (set_context) {
889 u32 sid = oldsbsec->mntpoint_sid;
890
891 if (!set_fscontext)
892 newsbsec->sid = sid;
893 if (!set_rootcontext) {
894 struct inode *newinode = newsb->s_root->d_inode;
895 struct inode_security_struct *newisec = newinode->i_security;
896 newisec->sid = sid;
897 }
898 newsbsec->mntpoint_sid = sid;
899 }
900 if (set_rootcontext) {
901 const struct inode *oldinode = oldsb->s_root->d_inode;
902 const struct inode_security_struct *oldisec = oldinode->i_security;
903 struct inode *newinode = newsb->s_root->d_inode;
904 struct inode_security_struct *newisec = newinode->i_security;
905
906 newisec->sid = oldisec->sid;
907 }
908
909 sb_finish_set_opts(newsb);
910 mutex_unlock(&newsbsec->lock);
911 return 0;
912}
913
914static int selinux_parse_opts_str(char *options,
915 struct security_mnt_opts *opts)
916{
917 char *p;
918 char *context = NULL, *defcontext = NULL;
919 char *fscontext = NULL, *rootcontext = NULL;
920 int rc, num_mnt_opts = 0;
921
922 opts->num_mnt_opts = 0;
923
924 /* Standard string-based options. */
925 while ((p = strsep(&options, "|")) != NULL) {
926 int token;
927 substring_t args[MAX_OPT_ARGS];
928
929 if (!*p)
930 continue;
931
932 token = match_token(p, tokens, args);
933
934 switch (token) {
935 case Opt_context:
936 if (context || defcontext) {
937 rc = -EINVAL;
938 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
939 goto out_err;
940 }
941 context = match_strdup(&args[0]);
942 if (!context) {
943 rc = -ENOMEM;
944 goto out_err;
945 }
946 break;
947
948 case Opt_fscontext:
949 if (fscontext) {
950 rc = -EINVAL;
951 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
952 goto out_err;
953 }
954 fscontext = match_strdup(&args[0]);
955 if (!fscontext) {
956 rc = -ENOMEM;
957 goto out_err;
958 }
959 break;
960
961 case Opt_rootcontext:
962 if (rootcontext) {
963 rc = -EINVAL;
964 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
965 goto out_err;
966 }
967 rootcontext = match_strdup(&args[0]);
968 if (!rootcontext) {
969 rc = -ENOMEM;
970 goto out_err;
971 }
972 break;
973
974 case Opt_defcontext:
975 if (context || defcontext) {
976 rc = -EINVAL;
977 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
978 goto out_err;
979 }
980 defcontext = match_strdup(&args[0]);
981 if (!defcontext) {
982 rc = -ENOMEM;
983 goto out_err;
984 }
985 break;
986 case Opt_labelsupport:
987 break;
988 default:
989 rc = -EINVAL;
990 printk(KERN_WARNING "SELinux: unknown mount option\n");
991 goto out_err;
992
993 }
994 }
995
996 rc = -ENOMEM;
997 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
998 if (!opts->mnt_opts)
999 goto out_err;
1000
1001 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
1002 if (!opts->mnt_opts_flags) {
1003 kfree(opts->mnt_opts);
1004 goto out_err;
1005 }
1006
1007 if (fscontext) {
1008 opts->mnt_opts[num_mnt_opts] = fscontext;
1009 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1010 }
1011 if (context) {
1012 opts->mnt_opts[num_mnt_opts] = context;
1013 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1014 }
1015 if (rootcontext) {
1016 opts->mnt_opts[num_mnt_opts] = rootcontext;
1017 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1018 }
1019 if (defcontext) {
1020 opts->mnt_opts[num_mnt_opts] = defcontext;
1021 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1022 }
1023
1024 opts->num_mnt_opts = num_mnt_opts;
1025 return 0;
1026
1027out_err:
1028 kfree(context);
1029 kfree(defcontext);
1030 kfree(fscontext);
1031 kfree(rootcontext);
1032 return rc;
1033}
1034/*
1035 * string mount options parsing and call set the sbsec
1036 */
1037static int superblock_doinit(struct super_block *sb, void *data)
1038{
1039 int rc = 0;
1040 char *options = data;
1041 struct security_mnt_opts opts;
1042
1043 security_init_mnt_opts(&opts);
1044
1045 if (!data)
1046 goto out;
1047
1048 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1049
1050 rc = selinux_parse_opts_str(options, &opts);
1051 if (rc)
1052 goto out_err;
1053
1054out:
1055 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1056
1057out_err:
1058 security_free_mnt_opts(&opts);
1059 return rc;
1060}
1061
1062static void selinux_write_opts(struct seq_file *m,
1063 struct security_mnt_opts *opts)
1064{
1065 int i;
1066 char *prefix;
1067
1068 for (i = 0; i < opts->num_mnt_opts; i++) {
1069 char *has_comma;
1070
1071 if (opts->mnt_opts[i])
1072 has_comma = strchr(opts->mnt_opts[i], ',');
1073 else
1074 has_comma = NULL;
1075
1076 switch (opts->mnt_opts_flags[i]) {
1077 case CONTEXT_MNT:
1078 prefix = CONTEXT_STR;
1079 break;
1080 case FSCONTEXT_MNT:
1081 prefix = FSCONTEXT_STR;
1082 break;
1083 case ROOTCONTEXT_MNT:
1084 prefix = ROOTCONTEXT_STR;
1085 break;
1086 case DEFCONTEXT_MNT:
1087 prefix = DEFCONTEXT_STR;
1088 break;
1089 case SBLABEL_MNT:
1090 seq_putc(m, ',');
1091 seq_puts(m, LABELSUPP_STR);
1092 continue;
1093 default:
1094 BUG();
1095 return;
1096 };
1097 /* we need a comma before each option */
1098 seq_putc(m, ',');
1099 seq_puts(m, prefix);
1100 if (has_comma)
1101 seq_putc(m, '\"');
1102 seq_puts(m, opts->mnt_opts[i]);
1103 if (has_comma)
1104 seq_putc(m, '\"');
1105 }
1106}
1107
1108static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1109{
1110 struct security_mnt_opts opts;
1111 int rc;
1112
1113 rc = selinux_get_mnt_opts(sb, &opts);
1114 if (rc) {
1115 /* before policy load we may get EINVAL, don't show anything */
1116 if (rc == -EINVAL)
1117 rc = 0;
1118 return rc;
1119 }
1120
1121 selinux_write_opts(m, &opts);
1122
1123 security_free_mnt_opts(&opts);
1124
1125 return rc;
1126}
1127
1128static inline u16 inode_mode_to_security_class(umode_t mode)
1129{
1130 switch (mode & S_IFMT) {
1131 case S_IFSOCK:
1132 return SECCLASS_SOCK_FILE;
1133 case S_IFLNK:
1134 return SECCLASS_LNK_FILE;
1135 case S_IFREG:
1136 return SECCLASS_FILE;
1137 case S_IFBLK:
1138 return SECCLASS_BLK_FILE;
1139 case S_IFDIR:
1140 return SECCLASS_DIR;
1141 case S_IFCHR:
1142 return SECCLASS_CHR_FILE;
1143 case S_IFIFO:
1144 return SECCLASS_FIFO_FILE;
1145
1146 }
1147
1148 return SECCLASS_FILE;
1149}
1150
1151static inline int default_protocol_stream(int protocol)
1152{
1153 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1154}
1155
1156static inline int default_protocol_dgram(int protocol)
1157{
1158 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1159}
1160
1161static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1162{
1163 switch (family) {
1164 case PF_UNIX:
1165 switch (type) {
1166 case SOCK_STREAM:
1167 case SOCK_SEQPACKET:
1168 return SECCLASS_UNIX_STREAM_SOCKET;
1169 case SOCK_DGRAM:
1170 return SECCLASS_UNIX_DGRAM_SOCKET;
1171 }
1172 break;
1173 case PF_INET:
1174 case PF_INET6:
1175 switch (type) {
1176 case SOCK_STREAM:
1177 if (default_protocol_stream(protocol))
1178 return SECCLASS_TCP_SOCKET;
1179 else
1180 return SECCLASS_RAWIP_SOCKET;
1181 case SOCK_DGRAM:
1182 if (default_protocol_dgram(protocol))
1183 return SECCLASS_UDP_SOCKET;
1184 else
1185 return SECCLASS_RAWIP_SOCKET;
1186 case SOCK_DCCP:
1187 return SECCLASS_DCCP_SOCKET;
1188 default:
1189 return SECCLASS_RAWIP_SOCKET;
1190 }
1191 break;
1192 case PF_NETLINK:
1193 switch (protocol) {
1194 case NETLINK_ROUTE:
1195 return SECCLASS_NETLINK_ROUTE_SOCKET;
1196 case NETLINK_FIREWALL:
1197 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1198 case NETLINK_SOCK_DIAG:
1199 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1200 case NETLINK_NFLOG:
1201 return SECCLASS_NETLINK_NFLOG_SOCKET;
1202 case NETLINK_XFRM:
1203 return SECCLASS_NETLINK_XFRM_SOCKET;
1204 case NETLINK_SELINUX:
1205 return SECCLASS_NETLINK_SELINUX_SOCKET;
1206 case NETLINK_AUDIT:
1207 return SECCLASS_NETLINK_AUDIT_SOCKET;
1208 case NETLINK_IP6_FW:
1209 return SECCLASS_NETLINK_IP6FW_SOCKET;
1210 case NETLINK_DNRTMSG:
1211 return SECCLASS_NETLINK_DNRT_SOCKET;
1212 case NETLINK_KOBJECT_UEVENT:
1213 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1214 default:
1215 return SECCLASS_NETLINK_SOCKET;
1216 }
1217 case PF_PACKET:
1218 return SECCLASS_PACKET_SOCKET;
1219 case PF_KEY:
1220 return SECCLASS_KEY_SOCKET;
1221 case PF_APPLETALK:
1222 return SECCLASS_APPLETALK_SOCKET;
1223 }
1224
1225 return SECCLASS_SOCKET;
1226}
1227
1228#ifdef CONFIG_PROC_FS
1229static int selinux_proc_get_sid(struct dentry *dentry,
1230 u16 tclass,
1231 u32 *sid)
1232{
1233 int rc;
1234 char *buffer, *path;
1235
1236 buffer = (char *)__get_free_page(GFP_KERNEL);
1237 if (!buffer)
1238 return -ENOMEM;
1239
1240 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1241 if (IS_ERR(path))
1242 rc = PTR_ERR(path);
1243 else {
1244 /* each process gets a /proc/PID/ entry. Strip off the
1245 * PID part to get a valid selinux labeling.
1246 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1247 while (path[1] >= '0' && path[1] <= '9') {
1248 path[1] = '/';
1249 path++;
1250 }
1251 rc = security_genfs_sid("proc", path, tclass, sid);
1252 }
1253 free_page((unsigned long)buffer);
1254 return rc;
1255}
1256#else
1257static int selinux_proc_get_sid(struct dentry *dentry,
1258 u16 tclass,
1259 u32 *sid)
1260{
1261 return -EINVAL;
1262}
1263#endif
1264
1265/* The inode's security attributes must be initialized before first use. */
1266static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1267{
1268 struct superblock_security_struct *sbsec = NULL;
1269 struct inode_security_struct *isec = inode->i_security;
1270 u32 sid;
1271 struct dentry *dentry;
1272#define INITCONTEXTLEN 255
1273 char *context = NULL;
1274 unsigned len = 0;
1275 int rc = 0;
1276
1277 if (isec->initialized)
1278 goto out;
1279
1280 mutex_lock(&isec->lock);
1281 if (isec->initialized)
1282 goto out_unlock;
1283
1284 sbsec = inode->i_sb->s_security;
1285 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1286 /* Defer initialization until selinux_complete_init,
1287 after the initial policy is loaded and the security
1288 server is ready to handle calls. */
1289 spin_lock(&sbsec->isec_lock);
1290 if (list_empty(&isec->list))
1291 list_add(&isec->list, &sbsec->isec_head);
1292 spin_unlock(&sbsec->isec_lock);
1293 goto out_unlock;
1294 }
1295
1296 switch (sbsec->behavior) {
1297 case SECURITY_FS_USE_NATIVE:
1298 break;
1299 case SECURITY_FS_USE_XATTR:
1300 if (!inode->i_op->getxattr) {
1301 isec->sid = sbsec->def_sid;
1302 break;
1303 }
1304
1305 /* Need a dentry, since the xattr API requires one.
1306 Life would be simpler if we could just pass the inode. */
1307 if (opt_dentry) {
1308 /* Called from d_instantiate or d_splice_alias. */
1309 dentry = dget(opt_dentry);
1310 } else {
1311 /* Called from selinux_complete_init, try to find a dentry. */
1312 dentry = d_find_alias(inode);
1313 }
1314 if (!dentry) {
1315 /*
1316 * this is can be hit on boot when a file is accessed
1317 * before the policy is loaded. When we load policy we
1318 * may find inodes that have no dentry on the
1319 * sbsec->isec_head list. No reason to complain as these
1320 * will get fixed up the next time we go through
1321 * inode_doinit with a dentry, before these inodes could
1322 * be used again by userspace.
1323 */
1324 goto out_unlock;
1325 }
1326
1327 len = INITCONTEXTLEN;
1328 context = kmalloc(len+1, GFP_NOFS);
1329 if (!context) {
1330 rc = -ENOMEM;
1331 dput(dentry);
1332 goto out_unlock;
1333 }
1334 context[len] = '\0';
1335 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1336 context, len);
1337 if (rc == -ERANGE) {
1338 kfree(context);
1339
1340 /* Need a larger buffer. Query for the right size. */
1341 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1342 NULL, 0);
1343 if (rc < 0) {
1344 dput(dentry);
1345 goto out_unlock;
1346 }
1347 len = rc;
1348 context = kmalloc(len+1, GFP_NOFS);
1349 if (!context) {
1350 rc = -ENOMEM;
1351 dput(dentry);
1352 goto out_unlock;
1353 }
1354 context[len] = '\0';
1355 rc = inode->i_op->getxattr(dentry,
1356 XATTR_NAME_SELINUX,
1357 context, len);
1358 }
1359 dput(dentry);
1360 if (rc < 0) {
1361 if (rc != -ENODATA) {
1362 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1363 "%d for dev=%s ino=%ld\n", __func__,
1364 -rc, inode->i_sb->s_id, inode->i_ino);
1365 kfree(context);
1366 goto out_unlock;
1367 }
1368 /* Map ENODATA to the default file SID */
1369 sid = sbsec->def_sid;
1370 rc = 0;
1371 } else {
1372 rc = security_context_to_sid_default(context, rc, &sid,
1373 sbsec->def_sid,
1374 GFP_NOFS);
1375 if (rc) {
1376 char *dev = inode->i_sb->s_id;
1377 unsigned long ino = inode->i_ino;
1378
1379 if (rc == -EINVAL) {
1380 if (printk_ratelimit())
1381 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1382 "context=%s. This indicates you may need to relabel the inode or the "
1383 "filesystem in question.\n", ino, dev, context);
1384 } else {
1385 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1386 "returned %d for dev=%s ino=%ld\n",
1387 __func__, context, -rc, dev, ino);
1388 }
1389 kfree(context);
1390 /* Leave with the unlabeled SID */
1391 rc = 0;
1392 break;
1393 }
1394 }
1395 kfree(context);
1396 isec->sid = sid;
1397 break;
1398 case SECURITY_FS_USE_TASK:
1399 isec->sid = isec->task_sid;
1400 break;
1401 case SECURITY_FS_USE_TRANS:
1402 /* Default to the fs SID. */
1403 isec->sid = sbsec->sid;
1404
1405 /* Try to obtain a transition SID. */
1406 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1407 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1408 isec->sclass, NULL, &sid);
1409 if (rc)
1410 goto out_unlock;
1411 isec->sid = sid;
1412 break;
1413 case SECURITY_FS_USE_MNTPOINT:
1414 isec->sid = sbsec->mntpoint_sid;
1415 break;
1416 default:
1417 /* Default to the fs superblock SID. */
1418 isec->sid = sbsec->sid;
1419
1420 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1421 /* We must have a dentry to determine the label on
1422 * procfs inodes */
1423 if (opt_dentry)
1424 /* Called from d_instantiate or
1425 * d_splice_alias. */
1426 dentry = dget(opt_dentry);
1427 else
1428 /* Called from selinux_complete_init, try to
1429 * find a dentry. */
1430 dentry = d_find_alias(inode);
1431 /*
1432 * This can be hit on boot when a file is accessed
1433 * before the policy is loaded. When we load policy we
1434 * may find inodes that have no dentry on the
1435 * sbsec->isec_head list. No reason to complain as
1436 * these will get fixed up the next time we go through
1437 * inode_doinit() with a dentry, before these inodes
1438 * could be used again by userspace.
1439 */
1440 if (!dentry)
1441 goto out_unlock;
1442 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1443 rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
1444 dput(dentry);
1445 if (rc)
1446 goto out_unlock;
1447 isec->sid = sid;
1448 }
1449 break;
1450 }
1451
1452 isec->initialized = 1;
1453
1454out_unlock:
1455 mutex_unlock(&isec->lock);
1456out:
1457 if (isec->sclass == SECCLASS_FILE)
1458 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1459 return rc;
1460}
1461
1462/* Convert a Linux signal to an access vector. */
1463static inline u32 signal_to_av(int sig)
1464{
1465 u32 perm = 0;
1466
1467 switch (sig) {
1468 case SIGCHLD:
1469 /* Commonly granted from child to parent. */
1470 perm = PROCESS__SIGCHLD;
1471 break;
1472 case SIGKILL:
1473 /* Cannot be caught or ignored */
1474 perm = PROCESS__SIGKILL;
1475 break;
1476 case SIGSTOP:
1477 /* Cannot be caught or ignored */
1478 perm = PROCESS__SIGSTOP;
1479 break;
1480 default:
1481 /* All other signals. */
1482 perm = PROCESS__SIGNAL;
1483 break;
1484 }
1485
1486 return perm;
1487}
1488
1489/*
1490 * Check permission between a pair of credentials
1491 * fork check, ptrace check, etc.
1492 */
1493static int cred_has_perm(const struct cred *actor,
1494 const struct cred *target,
1495 u32 perms)
1496{
1497 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1498
1499 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1500}
1501
1502/*
1503 * Check permission between a pair of tasks, e.g. signal checks,
1504 * fork check, ptrace check, etc.
1505 * tsk1 is the actor and tsk2 is the target
1506 * - this uses the default subjective creds of tsk1
1507 */
1508static int task_has_perm(const struct task_struct *tsk1,
1509 const struct task_struct *tsk2,
1510 u32 perms)
1511{
1512 const struct task_security_struct *__tsec1, *__tsec2;
1513 u32 sid1, sid2;
1514
1515 rcu_read_lock();
1516 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1517 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1518 rcu_read_unlock();
1519 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1520}
1521
1522/*
1523 * Check permission between current and another task, e.g. signal checks,
1524 * fork check, ptrace check, etc.
1525 * current is the actor and tsk2 is the target
1526 * - this uses current's subjective creds
1527 */
1528static int current_has_perm(const struct task_struct *tsk,
1529 u32 perms)
1530{
1531 u32 sid, tsid;
1532
1533 sid = current_sid();
1534 tsid = task_sid(tsk);
1535 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1536}
1537
1538#if CAP_LAST_CAP > 63
1539#error Fix SELinux to handle capabilities > 63.
1540#endif
1541
1542/* Check whether a task is allowed to use a capability. */
1543static int cred_has_capability(const struct cred *cred,
1544 int cap, int audit)
1545{
1546 struct common_audit_data ad;
1547 struct av_decision avd;
1548 u16 sclass;
1549 u32 sid = cred_sid(cred);
1550 u32 av = CAP_TO_MASK(cap);
1551 int rc;
1552
1553 ad.type = LSM_AUDIT_DATA_CAP;
1554 ad.u.cap = cap;
1555
1556 switch (CAP_TO_INDEX(cap)) {
1557 case 0:
1558 sclass = SECCLASS_CAPABILITY;
1559 break;
1560 case 1:
1561 sclass = SECCLASS_CAPABILITY2;
1562 break;
1563 default:
1564 printk(KERN_ERR
1565 "SELinux: out of range capability %d\n", cap);
1566 BUG();
1567 return -EINVAL;
1568 }
1569
1570 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1571 if (audit == SECURITY_CAP_AUDIT) {
1572 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1573 if (rc2)
1574 return rc2;
1575 }
1576 return rc;
1577}
1578
1579/* Check whether a task is allowed to use a system operation. */
1580static int task_has_system(struct task_struct *tsk,
1581 u32 perms)
1582{
1583 u32 sid = task_sid(tsk);
1584
1585 return avc_has_perm(sid, SECINITSID_KERNEL,
1586 SECCLASS_SYSTEM, perms, NULL);
1587}
1588
1589/* Check whether a task has a particular permission to an inode.
1590 The 'adp' parameter is optional and allows other audit
1591 data to be passed (e.g. the dentry). */
1592static int inode_has_perm(const struct cred *cred,
1593 struct inode *inode,
1594 u32 perms,
1595 struct common_audit_data *adp)
1596{
1597 struct inode_security_struct *isec;
1598 u32 sid;
1599
1600 validate_creds(cred);
1601
1602 if (unlikely(IS_PRIVATE(inode)))
1603 return 0;
1604
1605 sid = cred_sid(cred);
1606 isec = inode->i_security;
1607
1608 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1609}
1610
1611/* Same as inode_has_perm, but pass explicit audit data containing
1612 the dentry to help the auditing code to more easily generate the
1613 pathname if needed. */
1614static inline int dentry_has_perm(const struct cred *cred,
1615 struct dentry *dentry,
1616 u32 av)
1617{
1618 struct inode *inode = dentry->d_inode;
1619 struct common_audit_data ad;
1620
1621 ad.type = LSM_AUDIT_DATA_DENTRY;
1622 ad.u.dentry = dentry;
1623 return inode_has_perm(cred, inode, av, &ad);
1624}
1625
1626/* Same as inode_has_perm, but pass explicit audit data containing
1627 the path to help the auditing code to more easily generate the
1628 pathname if needed. */
1629static inline int path_has_perm(const struct cred *cred,
1630 struct path *path,
1631 u32 av)
1632{
1633 struct inode *inode = path->dentry->d_inode;
1634 struct common_audit_data ad;
1635
1636 ad.type = LSM_AUDIT_DATA_PATH;
1637 ad.u.path = *path;
1638 return inode_has_perm(cred, inode, av, &ad);
1639}
1640
1641/* Same as path_has_perm, but uses the inode from the file struct. */
1642static inline int file_path_has_perm(const struct cred *cred,
1643 struct file *file,
1644 u32 av)
1645{
1646 struct common_audit_data ad;
1647
1648 ad.type = LSM_AUDIT_DATA_PATH;
1649 ad.u.path = file->f_path;
1650 return inode_has_perm(cred, file_inode(file), av, &ad);
1651}
1652
1653/* Check whether a task can use an open file descriptor to
1654 access an inode in a given way. Check access to the
1655 descriptor itself, and then use dentry_has_perm to
1656 check a particular permission to the file.
1657 Access to the descriptor is implicitly granted if it
1658 has the same SID as the process. If av is zero, then
1659 access to the file is not checked, e.g. for cases
1660 where only the descriptor is affected like seek. */
1661static int file_has_perm(const struct cred *cred,
1662 struct file *file,
1663 u32 av)
1664{
1665 struct file_security_struct *fsec = file->f_security;
1666 struct inode *inode = file_inode(file);
1667 struct common_audit_data ad;
1668 u32 sid = cred_sid(cred);
1669 int rc;
1670
1671 ad.type = LSM_AUDIT_DATA_PATH;
1672 ad.u.path = file->f_path;
1673
1674 if (sid != fsec->sid) {
1675 rc = avc_has_perm(sid, fsec->sid,
1676 SECCLASS_FD,
1677 FD__USE,
1678 &ad);
1679 if (rc)
1680 goto out;
1681 }
1682
1683 /* av is zero if only checking access to the descriptor. */
1684 rc = 0;
1685 if (av)
1686 rc = inode_has_perm(cred, inode, av, &ad);
1687
1688out:
1689 return rc;
1690}
1691
1692/* Check whether a task can create a file. */
1693static int may_create(struct inode *dir,
1694 struct dentry *dentry,
1695 u16 tclass)
1696{
1697 const struct task_security_struct *tsec = current_security();
1698 struct inode_security_struct *dsec;
1699 struct superblock_security_struct *sbsec;
1700 u32 sid, newsid;
1701 struct common_audit_data ad;
1702 int rc;
1703
1704 dsec = dir->i_security;
1705 sbsec = dir->i_sb->s_security;
1706
1707 sid = tsec->sid;
1708 newsid = tsec->create_sid;
1709
1710 ad.type = LSM_AUDIT_DATA_DENTRY;
1711 ad.u.dentry = dentry;
1712
1713 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1714 DIR__ADD_NAME | DIR__SEARCH,
1715 &ad);
1716 if (rc)
1717 return rc;
1718
1719 if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1720 rc = security_transition_sid(sid, dsec->sid, tclass,
1721 &dentry->d_name, &newsid);
1722 if (rc)
1723 return rc;
1724 }
1725
1726 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1727 if (rc)
1728 return rc;
1729
1730 return avc_has_perm(newsid, sbsec->sid,
1731 SECCLASS_FILESYSTEM,
1732 FILESYSTEM__ASSOCIATE, &ad);
1733}
1734
1735/* Check whether a task can create a key. */
1736static int may_create_key(u32 ksid,
1737 struct task_struct *ctx)
1738{
1739 u32 sid = task_sid(ctx);
1740
1741 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1742}
1743
1744#define MAY_LINK 0
1745#define MAY_UNLINK 1
1746#define MAY_RMDIR 2
1747
1748/* Check whether a task can link, unlink, or rmdir a file/directory. */
1749static int may_link(struct inode *dir,
1750 struct dentry *dentry,
1751 int kind)
1752
1753{
1754 struct inode_security_struct *dsec, *isec;
1755 struct common_audit_data ad;
1756 u32 sid = current_sid();
1757 u32 av;
1758 int rc;
1759
1760 dsec = dir->i_security;
1761 isec = dentry->d_inode->i_security;
1762
1763 ad.type = LSM_AUDIT_DATA_DENTRY;
1764 ad.u.dentry = dentry;
1765
1766 av = DIR__SEARCH;
1767 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1768 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1769 if (rc)
1770 return rc;
1771
1772 switch (kind) {
1773 case MAY_LINK:
1774 av = FILE__LINK;
1775 break;
1776 case MAY_UNLINK:
1777 av = FILE__UNLINK;
1778 break;
1779 case MAY_RMDIR:
1780 av = DIR__RMDIR;
1781 break;
1782 default:
1783 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1784 __func__, kind);
1785 return 0;
1786 }
1787
1788 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1789 return rc;
1790}
1791
1792static inline int may_rename(struct inode *old_dir,
1793 struct dentry *old_dentry,
1794 struct inode *new_dir,
1795 struct dentry *new_dentry)
1796{
1797 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1798 struct common_audit_data ad;
1799 u32 sid = current_sid();
1800 u32 av;
1801 int old_is_dir, new_is_dir;
1802 int rc;
1803
1804 old_dsec = old_dir->i_security;
1805 old_isec = old_dentry->d_inode->i_security;
1806 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1807 new_dsec = new_dir->i_security;
1808
1809 ad.type = LSM_AUDIT_DATA_DENTRY;
1810
1811 ad.u.dentry = old_dentry;
1812 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1813 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1814 if (rc)
1815 return rc;
1816 rc = avc_has_perm(sid, old_isec->sid,
1817 old_isec->sclass, FILE__RENAME, &ad);
1818 if (rc)
1819 return rc;
1820 if (old_is_dir && new_dir != old_dir) {
1821 rc = avc_has_perm(sid, old_isec->sid,
1822 old_isec->sclass, DIR__REPARENT, &ad);
1823 if (rc)
1824 return rc;
1825 }
1826
1827 ad.u.dentry = new_dentry;
1828 av = DIR__ADD_NAME | DIR__SEARCH;
1829 if (new_dentry->d_inode)
1830 av |= DIR__REMOVE_NAME;
1831 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1832 if (rc)
1833 return rc;
1834 if (new_dentry->d_inode) {
1835 new_isec = new_dentry->d_inode->i_security;
1836 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1837 rc = avc_has_perm(sid, new_isec->sid,
1838 new_isec->sclass,
1839 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1840 if (rc)
1841 return rc;
1842 }
1843
1844 return 0;
1845}
1846
1847/* Check whether a task can perform a filesystem operation. */
1848static int superblock_has_perm(const struct cred *cred,
1849 struct super_block *sb,
1850 u32 perms,
1851 struct common_audit_data *ad)
1852{
1853 struct superblock_security_struct *sbsec;
1854 u32 sid = cred_sid(cred);
1855
1856 sbsec = sb->s_security;
1857 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1858}
1859
1860/* Convert a Linux mode and permission mask to an access vector. */
1861static inline u32 file_mask_to_av(int mode, int mask)
1862{
1863 u32 av = 0;
1864
1865 if (!S_ISDIR(mode)) {
1866 if (mask & MAY_EXEC)
1867 av |= FILE__EXECUTE;
1868 if (mask & MAY_READ)
1869 av |= FILE__READ;
1870
1871 if (mask & MAY_APPEND)
1872 av |= FILE__APPEND;
1873 else if (mask & MAY_WRITE)
1874 av |= FILE__WRITE;
1875
1876 } else {
1877 if (mask & MAY_EXEC)
1878 av |= DIR__SEARCH;
1879 if (mask & MAY_WRITE)
1880 av |= DIR__WRITE;
1881 if (mask & MAY_READ)
1882 av |= DIR__READ;
1883 }
1884
1885 return av;
1886}
1887
1888/* Convert a Linux file to an access vector. */
1889static inline u32 file_to_av(struct file *file)
1890{
1891 u32 av = 0;
1892
1893 if (file->f_mode & FMODE_READ)
1894 av |= FILE__READ;
1895 if (file->f_mode & FMODE_WRITE) {
1896 if (file->f_flags & O_APPEND)
1897 av |= FILE__APPEND;
1898 else
1899 av |= FILE__WRITE;
1900 }
1901 if (!av) {
1902 /*
1903 * Special file opened with flags 3 for ioctl-only use.
1904 */
1905 av = FILE__IOCTL;
1906 }
1907
1908 return av;
1909}
1910
1911/*
1912 * Convert a file to an access vector and include the correct open
1913 * open permission.
1914 */
1915static inline u32 open_file_to_av(struct file *file)
1916{
1917 u32 av = file_to_av(file);
1918
1919 if (selinux_policycap_openperm)
1920 av |= FILE__OPEN;
1921
1922 return av;
1923}
1924
1925/* Hook functions begin here. */
1926
1927static int selinux_ptrace_access_check(struct task_struct *child,
1928 unsigned int mode)
1929{
1930 int rc;
1931
1932 rc = cap_ptrace_access_check(child, mode);
1933 if (rc)
1934 return rc;
1935
1936 if (mode & PTRACE_MODE_READ) {
1937 u32 sid = current_sid();
1938 u32 csid = task_sid(child);
1939 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1940 }
1941
1942 return current_has_perm(child, PROCESS__PTRACE);
1943}
1944
1945static int selinux_ptrace_traceme(struct task_struct *parent)
1946{
1947 int rc;
1948
1949 rc = cap_ptrace_traceme(parent);
1950 if (rc)
1951 return rc;
1952
1953 return task_has_perm(parent, current, PROCESS__PTRACE);
1954}
1955
1956static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1957 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1958{
1959 int error;
1960
1961 error = current_has_perm(target, PROCESS__GETCAP);
1962 if (error)
1963 return error;
1964
1965 return cap_capget(target, effective, inheritable, permitted);
1966}
1967
1968static int selinux_capset(struct cred *new, const struct cred *old,
1969 const kernel_cap_t *effective,
1970 const kernel_cap_t *inheritable,
1971 const kernel_cap_t *permitted)
1972{
1973 int error;
1974
1975 error = cap_capset(new, old,
1976 effective, inheritable, permitted);
1977 if (error)
1978 return error;
1979
1980 return cred_has_perm(old, new, PROCESS__SETCAP);
1981}
1982
1983/*
1984 * (This comment used to live with the selinux_task_setuid hook,
1985 * which was removed).
1986 *
1987 * Since setuid only affects the current process, and since the SELinux
1988 * controls are not based on the Linux identity attributes, SELinux does not
1989 * need to control this operation. However, SELinux does control the use of
1990 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1991 */
1992
1993static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1994 int cap, int audit)
1995{
1996 int rc;
1997
1998 rc = cap_capable(cred, ns, cap, audit);
1999 if (rc)
2000 return rc;
2001
2002 return cred_has_capability(cred, cap, audit);
2003}
2004
2005static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2006{
2007 const struct cred *cred = current_cred();
2008 int rc = 0;
2009
2010 if (!sb)
2011 return 0;
2012
2013 switch (cmds) {
2014 case Q_SYNC:
2015 case Q_QUOTAON:
2016 case Q_QUOTAOFF:
2017 case Q_SETINFO:
2018 case Q_SETQUOTA:
2019 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2020 break;
2021 case Q_GETFMT:
2022 case Q_GETINFO:
2023 case Q_GETQUOTA:
2024 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2025 break;
2026 default:
2027 rc = 0; /* let the kernel handle invalid cmds */
2028 break;
2029 }
2030 return rc;
2031}
2032
2033static int selinux_quota_on(struct dentry *dentry)
2034{
2035 const struct cred *cred = current_cred();
2036
2037 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2038}
2039
2040static int selinux_syslog(int type)
2041{
2042 int rc;
2043
2044 switch (type) {
2045 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2046 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2047 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2048 break;
2049 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2050 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2051 /* Set level of messages printed to console */
2052 case SYSLOG_ACTION_CONSOLE_LEVEL:
2053 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2054 break;
2055 case SYSLOG_ACTION_CLOSE: /* Close log */
2056 case SYSLOG_ACTION_OPEN: /* Open log */
2057 case SYSLOG_ACTION_READ: /* Read from log */
2058 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2059 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2060 default:
2061 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2062 break;
2063 }
2064 return rc;
2065}
2066
2067/*
2068 * Check that a process has enough memory to allocate a new virtual
2069 * mapping. 0 means there is enough memory for the allocation to
2070 * succeed and -ENOMEM implies there is not.
2071 *
2072 * Do not audit the selinux permission check, as this is applied to all
2073 * processes that allocate mappings.
2074 */
2075static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2076{
2077 int rc, cap_sys_admin = 0;
2078
2079 rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2080 SECURITY_CAP_NOAUDIT);
2081 if (rc == 0)
2082 cap_sys_admin = 1;
2083
2084 return __vm_enough_memory(mm, pages, cap_sys_admin);
2085}
2086
2087/* binprm security operations */
2088
2089static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2090{
2091 const struct task_security_struct *old_tsec;
2092 struct task_security_struct *new_tsec;
2093 struct inode_security_struct *isec;
2094 struct common_audit_data ad;
2095 struct inode *inode = file_inode(bprm->file);
2096 int rc;
2097
2098 rc = cap_bprm_set_creds(bprm);
2099 if (rc)
2100 return rc;
2101
2102 /* SELinux context only depends on initial program or script and not
2103 * the script interpreter */
2104 if (bprm->cred_prepared)
2105 return 0;
2106
2107 old_tsec = current_security();
2108 new_tsec = bprm->cred->security;
2109 isec = inode->i_security;
2110
2111 /* Default to the current task SID. */
2112 new_tsec->sid = old_tsec->sid;
2113 new_tsec->osid = old_tsec->sid;
2114
2115 /* Reset fs, key, and sock SIDs on execve. */
2116 new_tsec->create_sid = 0;
2117 new_tsec->keycreate_sid = 0;
2118 new_tsec->sockcreate_sid = 0;
2119
2120 if (old_tsec->exec_sid) {
2121 new_tsec->sid = old_tsec->exec_sid;
2122 /* Reset exec SID on execve. */
2123 new_tsec->exec_sid = 0;
2124
2125 /*
2126 * Minimize confusion: if no_new_privs and a transition is
2127 * explicitly requested, then fail the exec.
2128 */
2129 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2130 return -EPERM;
2131 } else {
2132 /* Check for a default transition on this program. */
2133 rc = security_transition_sid(old_tsec->sid, isec->sid,
2134 SECCLASS_PROCESS, NULL,
2135 &new_tsec->sid);
2136 if (rc)
2137 return rc;
2138 }
2139
2140 ad.type = LSM_AUDIT_DATA_PATH;
2141 ad.u.path = bprm->file->f_path;
2142
2143 if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2144 (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2145 new_tsec->sid = old_tsec->sid;
2146
2147 if (new_tsec->sid == old_tsec->sid) {
2148 rc = avc_has_perm(old_tsec->sid, isec->sid,
2149 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2150 if (rc)
2151 return rc;
2152 } else {
2153 /* Check permissions for the transition. */
2154 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2155 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2156 if (rc)
2157 return rc;
2158
2159 rc = avc_has_perm(new_tsec->sid, isec->sid,
2160 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2161 if (rc)
2162 return rc;
2163
2164 /* Check for shared state */
2165 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2166 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2167 SECCLASS_PROCESS, PROCESS__SHARE,
2168 NULL);
2169 if (rc)
2170 return -EPERM;
2171 }
2172
2173 /* Make sure that anyone attempting to ptrace over a task that
2174 * changes its SID has the appropriate permit */
2175 if (bprm->unsafe &
2176 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2177 struct task_struct *tracer;
2178 struct task_security_struct *sec;
2179 u32 ptsid = 0;
2180
2181 rcu_read_lock();
2182 tracer = ptrace_parent(current);
2183 if (likely(tracer != NULL)) {
2184 sec = __task_cred(tracer)->security;
2185 ptsid = sec->sid;
2186 }
2187 rcu_read_unlock();
2188
2189 if (ptsid != 0) {
2190 rc = avc_has_perm(ptsid, new_tsec->sid,
2191 SECCLASS_PROCESS,
2192 PROCESS__PTRACE, NULL);
2193 if (rc)
2194 return -EPERM;
2195 }
2196 }
2197
2198 /* Clear any possibly unsafe personality bits on exec: */
2199 bprm->per_clear |= PER_CLEAR_ON_SETID;
2200 }
2201
2202 return 0;
2203}
2204
2205static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2206{
2207 const struct task_security_struct *tsec = current_security();
2208 u32 sid, osid;
2209 int atsecure = 0;
2210
2211 sid = tsec->sid;
2212 osid = tsec->osid;
2213
2214 if (osid != sid) {
2215 /* Enable secure mode for SIDs transitions unless
2216 the noatsecure permission is granted between
2217 the two SIDs, i.e. ahp returns 0. */
2218 atsecure = avc_has_perm(osid, sid,
2219 SECCLASS_PROCESS,
2220 PROCESS__NOATSECURE, NULL);
2221 }
2222
2223 return (atsecure || cap_bprm_secureexec(bprm));
2224}
2225
2226static int match_file(const void *p, struct file *file, unsigned fd)
2227{
2228 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2229}
2230
2231/* Derived from fs/exec.c:flush_old_files. */
2232static inline void flush_unauthorized_files(const struct cred *cred,
2233 struct files_struct *files)
2234{
2235 struct file *file, *devnull = NULL;
2236 struct tty_struct *tty;
2237 int drop_tty = 0;
2238 unsigned n;
2239
2240 tty = get_current_tty();
2241 if (tty) {
2242 spin_lock(&tty_files_lock);
2243 if (!list_empty(&tty->tty_files)) {
2244 struct tty_file_private *file_priv;
2245
2246 /* Revalidate access to controlling tty.
2247 Use file_path_has_perm on the tty path directly
2248 rather than using file_has_perm, as this particular
2249 open file may belong to another process and we are
2250 only interested in the inode-based check here. */
2251 file_priv = list_first_entry(&tty->tty_files,
2252 struct tty_file_private, list);
2253 file = file_priv->file;
2254 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2255 drop_tty = 1;
2256 }
2257 spin_unlock(&tty_files_lock);
2258 tty_kref_put(tty);
2259 }
2260 /* Reset controlling tty. */
2261 if (drop_tty)
2262 no_tty();
2263
2264 /* Revalidate access to inherited open files. */
2265 n = iterate_fd(files, 0, match_file, cred);
2266 if (!n) /* none found? */
2267 return;
2268
2269 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2270 if (IS_ERR(devnull))
2271 devnull = NULL;
2272 /* replace all the matching ones with this */
2273 do {
2274 replace_fd(n - 1, devnull, 0);
2275 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2276 if (devnull)
2277 fput(devnull);
2278}
2279
2280/*
2281 * Prepare a process for imminent new credential changes due to exec
2282 */
2283static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2284{
2285 struct task_security_struct *new_tsec;
2286 struct rlimit *rlim, *initrlim;
2287 int rc, i;
2288
2289 new_tsec = bprm->cred->security;
2290 if (new_tsec->sid == new_tsec->osid)
2291 return;
2292
2293 /* Close files for which the new task SID is not authorized. */
2294 flush_unauthorized_files(bprm->cred, current->files);
2295
2296 /* Always clear parent death signal on SID transitions. */
2297 current->pdeath_signal = 0;
2298
2299 /* Check whether the new SID can inherit resource limits from the old
2300 * SID. If not, reset all soft limits to the lower of the current
2301 * task's hard limit and the init task's soft limit.
2302 *
2303 * Note that the setting of hard limits (even to lower them) can be
2304 * controlled by the setrlimit check. The inclusion of the init task's
2305 * soft limit into the computation is to avoid resetting soft limits
2306 * higher than the default soft limit for cases where the default is
2307 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2308 */
2309 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2310 PROCESS__RLIMITINH, NULL);
2311 if (rc) {
2312 /* protect against do_prlimit() */
2313 task_lock(current);
2314 for (i = 0; i < RLIM_NLIMITS; i++) {
2315 rlim = current->signal->rlim + i;
2316 initrlim = init_task.signal->rlim + i;
2317 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2318 }
2319 task_unlock(current);
2320 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2321 }
2322}
2323
2324/*
2325 * Clean up the process immediately after the installation of new credentials
2326 * due to exec
2327 */
2328static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2329{
2330 const struct task_security_struct *tsec = current_security();
2331 struct itimerval itimer;
2332 u32 osid, sid;
2333 int rc, i;
2334
2335 osid = tsec->osid;
2336 sid = tsec->sid;
2337
2338 if (sid == osid)
2339 return;
2340
2341 /* Check whether the new SID can inherit signal state from the old SID.
2342 * If not, clear itimers to avoid subsequent signal generation and
2343 * flush and unblock signals.
2344 *
2345 * This must occur _after_ the task SID has been updated so that any
2346 * kill done after the flush will be checked against the new SID.
2347 */
2348 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2349 if (rc) {
2350 memset(&itimer, 0, sizeof itimer);
2351 for (i = 0; i < 3; i++)
2352 do_setitimer(i, &itimer, NULL);
2353 spin_lock_irq(¤t->sighand->siglock);
2354 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2355 __flush_signals(current);
2356 flush_signal_handlers(current, 1);
2357 sigemptyset(¤t->blocked);
2358 }
2359 spin_unlock_irq(¤t->sighand->siglock);
2360 }
2361
2362 /* Wake up the parent if it is waiting so that it can recheck
2363 * wait permission to the new task SID. */
2364 read_lock(&tasklist_lock);
2365 __wake_up_parent(current, current->real_parent);
2366 read_unlock(&tasklist_lock);
2367}
2368
2369/* superblock security operations */
2370
2371static int selinux_sb_alloc_security(struct super_block *sb)
2372{
2373 return superblock_alloc_security(sb);
2374}
2375
2376static void selinux_sb_free_security(struct super_block *sb)
2377{
2378 superblock_free_security(sb);
2379}
2380
2381static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2382{
2383 if (plen > olen)
2384 return 0;
2385
2386 return !memcmp(prefix, option, plen);
2387}
2388
2389static inline int selinux_option(char *option, int len)
2390{
2391 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2392 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2393 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2394 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2395 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2396}
2397
2398static inline void take_option(char **to, char *from, int *first, int len)
2399{
2400 if (!*first) {
2401 **to = ',';
2402 *to += 1;
2403 } else
2404 *first = 0;
2405 memcpy(*to, from, len);
2406 *to += len;
2407}
2408
2409static inline void take_selinux_option(char **to, char *from, int *first,
2410 int len)
2411{
2412 int current_size = 0;
2413
2414 if (!*first) {
2415 **to = '|';
2416 *to += 1;
2417 } else
2418 *first = 0;
2419
2420 while (current_size < len) {
2421 if (*from != '"') {
2422 **to = *from;
2423 *to += 1;
2424 }
2425 from += 1;
2426 current_size += 1;
2427 }
2428}
2429
2430static int selinux_sb_copy_data(char *orig, char *copy)
2431{
2432 int fnosec, fsec, rc = 0;
2433 char *in_save, *in_curr, *in_end;
2434 char *sec_curr, *nosec_save, *nosec;
2435 int open_quote = 0;
2436
2437 in_curr = orig;
2438 sec_curr = copy;
2439
2440 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2441 if (!nosec) {
2442 rc = -ENOMEM;
2443 goto out;
2444 }
2445
2446 nosec_save = nosec;
2447 fnosec = fsec = 1;
2448 in_save = in_end = orig;
2449
2450 do {
2451 if (*in_end == '"')
2452 open_quote = !open_quote;
2453 if ((*in_end == ',' && open_quote == 0) ||
2454 *in_end == '\0') {
2455 int len = in_end - in_curr;
2456
2457 if (selinux_option(in_curr, len))
2458 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2459 else
2460 take_option(&nosec, in_curr, &fnosec, len);
2461
2462 in_curr = in_end + 1;
2463 }
2464 } while (*in_end++);
2465
2466 strcpy(in_save, nosec_save);
2467 free_page((unsigned long)nosec_save);
2468out:
2469 return rc;
2470}
2471
2472static int selinux_sb_remount(struct super_block *sb, void *data)
2473{
2474 int rc, i, *flags;
2475 struct security_mnt_opts opts;
2476 char *secdata, **mount_options;
2477 struct superblock_security_struct *sbsec = sb->s_security;
2478
2479 if (!(sbsec->flags & SE_SBINITIALIZED))
2480 return 0;
2481
2482 if (!data)
2483 return 0;
2484
2485 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2486 return 0;
2487
2488 security_init_mnt_opts(&opts);
2489 secdata = alloc_secdata();
2490 if (!secdata)
2491 return -ENOMEM;
2492 rc = selinux_sb_copy_data(data, secdata);
2493 if (rc)
2494 goto out_free_secdata;
2495
2496 rc = selinux_parse_opts_str(secdata, &opts);
2497 if (rc)
2498 goto out_free_secdata;
2499
2500 mount_options = opts.mnt_opts;
2501 flags = opts.mnt_opts_flags;
2502
2503 for (i = 0; i < opts.num_mnt_opts; i++) {
2504 u32 sid;
2505 size_t len;
2506
2507 if (flags[i] == SBLABEL_MNT)
2508 continue;
2509 len = strlen(mount_options[i]);
2510 rc = security_context_to_sid(mount_options[i], len, &sid,
2511 GFP_KERNEL);
2512 if (rc) {
2513 printk(KERN_WARNING "SELinux: security_context_to_sid"
2514 "(%s) failed for (dev %s, type %s) errno=%d\n",
2515 mount_options[i], sb->s_id, sb->s_type->name, rc);
2516 goto out_free_opts;
2517 }
2518 rc = -EINVAL;
2519 switch (flags[i]) {
2520 case FSCONTEXT_MNT:
2521 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2522 goto out_bad_option;
2523 break;
2524 case CONTEXT_MNT:
2525 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2526 goto out_bad_option;
2527 break;
2528 case ROOTCONTEXT_MNT: {
2529 struct inode_security_struct *root_isec;
2530 root_isec = sb->s_root->d_inode->i_security;
2531
2532 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2533 goto out_bad_option;
2534 break;
2535 }
2536 case DEFCONTEXT_MNT:
2537 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2538 goto out_bad_option;
2539 break;
2540 default:
2541 goto out_free_opts;
2542 }
2543 }
2544
2545 rc = 0;
2546out_free_opts:
2547 security_free_mnt_opts(&opts);
2548out_free_secdata:
2549 free_secdata(secdata);
2550 return rc;
2551out_bad_option:
2552 printk(KERN_WARNING "SELinux: unable to change security options "
2553 "during remount (dev %s, type=%s)\n", sb->s_id,
2554 sb->s_type->name);
2555 goto out_free_opts;
2556}
2557
2558static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2559{
2560 const struct cred *cred = current_cred();
2561 struct common_audit_data ad;
2562 int rc;
2563
2564 rc = superblock_doinit(sb, data);
2565 if (rc)
2566 return rc;
2567
2568 /* Allow all mounts performed by the kernel */
2569 if (flags & MS_KERNMOUNT)
2570 return 0;
2571
2572 ad.type = LSM_AUDIT_DATA_DENTRY;
2573 ad.u.dentry = sb->s_root;
2574 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2575}
2576
2577static int selinux_sb_statfs(struct dentry *dentry)
2578{
2579 const struct cred *cred = current_cred();
2580 struct common_audit_data ad;
2581
2582 ad.type = LSM_AUDIT_DATA_DENTRY;
2583 ad.u.dentry = dentry->d_sb->s_root;
2584 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2585}
2586
2587static int selinux_mount(const char *dev_name,
2588 struct path *path,
2589 const char *type,
2590 unsigned long flags,
2591 void *data)
2592{
2593 const struct cred *cred = current_cred();
2594
2595 if (flags & MS_REMOUNT)
2596 return superblock_has_perm(cred, path->dentry->d_sb,
2597 FILESYSTEM__REMOUNT, NULL);
2598 else
2599 return path_has_perm(cred, path, FILE__MOUNTON);
2600}
2601
2602static int selinux_umount(struct vfsmount *mnt, int flags)
2603{
2604 const struct cred *cred = current_cred();
2605
2606 return superblock_has_perm(cred, mnt->mnt_sb,
2607 FILESYSTEM__UNMOUNT, NULL);
2608}
2609
2610/* inode security operations */
2611
2612static int selinux_inode_alloc_security(struct inode *inode)
2613{
2614 return inode_alloc_security(inode);
2615}
2616
2617static void selinux_inode_free_security(struct inode *inode)
2618{
2619 inode_free_security(inode);
2620}
2621
2622static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2623 struct qstr *name, void **ctx,
2624 u32 *ctxlen)
2625{
2626 const struct cred *cred = current_cred();
2627 struct task_security_struct *tsec;
2628 struct inode_security_struct *dsec;
2629 struct superblock_security_struct *sbsec;
2630 struct inode *dir = dentry->d_parent->d_inode;
2631 u32 newsid;
2632 int rc;
2633
2634 tsec = cred->security;
2635 dsec = dir->i_security;
2636 sbsec = dir->i_sb->s_security;
2637
2638 if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2639 newsid = tsec->create_sid;
2640 } else {
2641 rc = security_transition_sid(tsec->sid, dsec->sid,
2642 inode_mode_to_security_class(mode),
2643 name,
2644 &newsid);
2645 if (rc) {
2646 printk(KERN_WARNING
2647 "%s: security_transition_sid failed, rc=%d\n",
2648 __func__, -rc);
2649 return rc;
2650 }
2651 }
2652
2653 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2654}
2655
2656static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2657 const struct qstr *qstr,
2658 const char **name,
2659 void **value, size_t *len)
2660{
2661 const struct task_security_struct *tsec = current_security();
2662 struct inode_security_struct *dsec;
2663 struct superblock_security_struct *sbsec;
2664 u32 sid, newsid, clen;
2665 int rc;
2666 char *context;
2667
2668 dsec = dir->i_security;
2669 sbsec = dir->i_sb->s_security;
2670
2671 sid = tsec->sid;
2672 newsid = tsec->create_sid;
2673
2674 if ((sbsec->flags & SE_SBINITIALIZED) &&
2675 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2676 newsid = sbsec->mntpoint_sid;
2677 else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2678 rc = security_transition_sid(sid, dsec->sid,
2679 inode_mode_to_security_class(inode->i_mode),
2680 qstr, &newsid);
2681 if (rc) {
2682 printk(KERN_WARNING "%s: "
2683 "security_transition_sid failed, rc=%d (dev=%s "
2684 "ino=%ld)\n",
2685 __func__,
2686 -rc, inode->i_sb->s_id, inode->i_ino);
2687 return rc;
2688 }
2689 }
2690
2691 /* Possibly defer initialization to selinux_complete_init. */
2692 if (sbsec->flags & SE_SBINITIALIZED) {
2693 struct inode_security_struct *isec = inode->i_security;
2694 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2695 isec->sid = newsid;
2696 isec->initialized = 1;
2697 }
2698
2699 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2700 return -EOPNOTSUPP;
2701
2702 if (name)
2703 *name = XATTR_SELINUX_SUFFIX;
2704
2705 if (value && len) {
2706 rc = security_sid_to_context_force(newsid, &context, &clen);
2707 if (rc)
2708 return rc;
2709 *value = context;
2710 *len = clen;
2711 }
2712
2713 return 0;
2714}
2715
2716static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2717{
2718 return may_create(dir, dentry, SECCLASS_FILE);
2719}
2720
2721static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2722{
2723 return may_link(dir, old_dentry, MAY_LINK);
2724}
2725
2726static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2727{
2728 return may_link(dir, dentry, MAY_UNLINK);
2729}
2730
2731static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2732{
2733 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2734}
2735
2736static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2737{
2738 return may_create(dir, dentry, SECCLASS_DIR);
2739}
2740
2741static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2742{
2743 return may_link(dir, dentry, MAY_RMDIR);
2744}
2745
2746static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2747{
2748 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2749}
2750
2751static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2752 struct inode *new_inode, struct dentry *new_dentry)
2753{
2754 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2755}
2756
2757static int selinux_inode_readlink(struct dentry *dentry)
2758{
2759 const struct cred *cred = current_cred();
2760
2761 return dentry_has_perm(cred, dentry, FILE__READ);
2762}
2763
2764static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2765{
2766 const struct cred *cred = current_cred();
2767
2768 return dentry_has_perm(cred, dentry, FILE__READ);
2769}
2770
2771static noinline int audit_inode_permission(struct inode *inode,
2772 u32 perms, u32 audited, u32 denied,
2773 unsigned flags)
2774{
2775 struct common_audit_data ad;
2776 struct inode_security_struct *isec = inode->i_security;
2777 int rc;
2778
2779 ad.type = LSM_AUDIT_DATA_INODE;
2780 ad.u.inode = inode;
2781
2782 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2783 audited, denied, &ad, flags);
2784 if (rc)
2785 return rc;
2786 return 0;
2787}
2788
2789static int selinux_inode_permission(struct inode *inode, int mask)
2790{
2791 const struct cred *cred = current_cred();
2792 u32 perms;
2793 bool from_access;
2794 unsigned flags = mask & MAY_NOT_BLOCK;
2795 struct inode_security_struct *isec;
2796 u32 sid;
2797 struct av_decision avd;
2798 int rc, rc2;
2799 u32 audited, denied;
2800
2801 from_access = mask & MAY_ACCESS;
2802 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2803
2804 /* No permission to check. Existence test. */
2805 if (!mask)
2806 return 0;
2807
2808 validate_creds(cred);
2809
2810 if (unlikely(IS_PRIVATE(inode)))
2811 return 0;
2812
2813 perms = file_mask_to_av(inode->i_mode, mask);
2814
2815 sid = cred_sid(cred);
2816 isec = inode->i_security;
2817
2818 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2819 audited = avc_audit_required(perms, &avd, rc,
2820 from_access ? FILE__AUDIT_ACCESS : 0,
2821 &denied);
2822 if (likely(!audited))
2823 return rc;
2824
2825 rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2826 if (rc2)
2827 return rc2;
2828 return rc;
2829}
2830
2831static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2832{
2833 const struct cred *cred = current_cred();
2834 unsigned int ia_valid = iattr->ia_valid;
2835 __u32 av = FILE__WRITE;
2836
2837 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2838 if (ia_valid & ATTR_FORCE) {
2839 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2840 ATTR_FORCE);
2841 if (!ia_valid)
2842 return 0;
2843 }
2844
2845 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2846 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2847 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2848
2849 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2850 av |= FILE__OPEN;
2851
2852 return dentry_has_perm(cred, dentry, av);
2853}
2854
2855static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2856{
2857 const struct cred *cred = current_cred();
2858 struct path path;
2859
2860 path.dentry = dentry;
2861 path.mnt = mnt;
2862
2863 return path_has_perm(cred, &path, FILE__GETATTR);
2864}
2865
2866static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2867{
2868 const struct cred *cred = current_cred();
2869
2870 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2871 sizeof XATTR_SECURITY_PREFIX - 1)) {
2872 if (!strcmp(name, XATTR_NAME_CAPS)) {
2873 if (!capable(CAP_SETFCAP))
2874 return -EPERM;
2875 } else if (!capable(CAP_SYS_ADMIN)) {
2876 /* A different attribute in the security namespace.
2877 Restrict to administrator. */
2878 return -EPERM;
2879 }
2880 }
2881
2882 /* Not an attribute we recognize, so just check the
2883 ordinary setattr permission. */
2884 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2885}
2886
2887static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2888 const void *value, size_t size, int flags)
2889{
2890 struct inode *inode = dentry->d_inode;
2891 struct inode_security_struct *isec = inode->i_security;
2892 struct superblock_security_struct *sbsec;
2893 struct common_audit_data ad;
2894 u32 newsid, sid = current_sid();
2895 int rc = 0;
2896
2897 if (strcmp(name, XATTR_NAME_SELINUX))
2898 return selinux_inode_setotherxattr(dentry, name);
2899
2900 sbsec = inode->i_sb->s_security;
2901 if (!(sbsec->flags & SBLABEL_MNT))
2902 return -EOPNOTSUPP;
2903
2904 if (!inode_owner_or_capable(inode))
2905 return -EPERM;
2906
2907 ad.type = LSM_AUDIT_DATA_DENTRY;
2908 ad.u.dentry = dentry;
2909
2910 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2911 FILE__RELABELFROM, &ad);
2912 if (rc)
2913 return rc;
2914
2915 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2916 if (rc == -EINVAL) {
2917 if (!capable(CAP_MAC_ADMIN)) {
2918 struct audit_buffer *ab;
2919 size_t audit_size;
2920 const char *str;
2921
2922 /* We strip a nul only if it is at the end, otherwise the
2923 * context contains a nul and we should audit that */
2924 if (value) {
2925 str = value;
2926 if (str[size - 1] == '\0')
2927 audit_size = size - 1;
2928 else
2929 audit_size = size;
2930 } else {
2931 str = "";
2932 audit_size = 0;
2933 }
2934 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2935 audit_log_format(ab, "op=setxattr invalid_context=");
2936 audit_log_n_untrustedstring(ab, value, audit_size);
2937 audit_log_end(ab);
2938
2939 return rc;
2940 }
2941 rc = security_context_to_sid_force(value, size, &newsid);
2942 }
2943 if (rc)
2944 return rc;
2945
2946 rc = avc_has_perm(sid, newsid, isec->sclass,
2947 FILE__RELABELTO, &ad);
2948 if (rc)
2949 return rc;
2950
2951 rc = security_validate_transition(isec->sid, newsid, sid,
2952 isec->sclass);
2953 if (rc)
2954 return rc;
2955
2956 return avc_has_perm(newsid,
2957 sbsec->sid,
2958 SECCLASS_FILESYSTEM,
2959 FILESYSTEM__ASSOCIATE,
2960 &ad);
2961}
2962
2963static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2964 const void *value, size_t size,
2965 int flags)
2966{
2967 struct inode *inode = dentry->d_inode;
2968 struct inode_security_struct *isec = inode->i_security;
2969 u32 newsid;
2970 int rc;
2971
2972 if (strcmp(name, XATTR_NAME_SELINUX)) {
2973 /* Not an attribute we recognize, so nothing to do. */
2974 return;
2975 }
2976
2977 rc = security_context_to_sid_force(value, size, &newsid);
2978 if (rc) {
2979 printk(KERN_ERR "SELinux: unable to map context to SID"
2980 "for (%s, %lu), rc=%d\n",
2981 inode->i_sb->s_id, inode->i_ino, -rc);
2982 return;
2983 }
2984
2985 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2986 isec->sid = newsid;
2987 isec->initialized = 1;
2988
2989 return;
2990}
2991
2992static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2993{
2994 const struct cred *cred = current_cred();
2995
2996 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2997}
2998
2999static int selinux_inode_listxattr(struct dentry *dentry)
3000{
3001 const struct cred *cred = current_cred();
3002
3003 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3004}
3005
3006static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3007{
3008 if (strcmp(name, XATTR_NAME_SELINUX))
3009 return selinux_inode_setotherxattr(dentry, name);
3010
3011 /* No one is allowed to remove a SELinux security label.
3012 You can change the label, but all data must be labeled. */
3013 return -EACCES;
3014}
3015
3016/*
3017 * Copy the inode security context value to the user.
3018 *
3019 * Permission check is handled by selinux_inode_getxattr hook.
3020 */
3021static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
3022{
3023 u32 size;
3024 int error;
3025 char *context = NULL;
3026 struct inode_security_struct *isec = inode->i_security;
3027
3028 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3029 return -EOPNOTSUPP;
3030
3031 /*
3032 * If the caller has CAP_MAC_ADMIN, then get the raw context
3033 * value even if it is not defined by current policy; otherwise,
3034 * use the in-core value under current policy.
3035 * Use the non-auditing forms of the permission checks since
3036 * getxattr may be called by unprivileged processes commonly
3037 * and lack of permission just means that we fall back to the
3038 * in-core context value, not a denial.
3039 */
3040 error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3041 SECURITY_CAP_NOAUDIT);
3042 if (!error)
3043 error = security_sid_to_context_force(isec->sid, &context,
3044 &size);
3045 else
3046 error = security_sid_to_context(isec->sid, &context, &size);
3047 if (error)
3048 return error;
3049 error = size;
3050 if (alloc) {
3051 *buffer = context;
3052 goto out_nofree;
3053 }
3054 kfree(context);
3055out_nofree:
3056 return error;
3057}
3058
3059static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3060 const void *value, size_t size, int flags)
3061{
3062 struct inode_security_struct *isec = inode->i_security;
3063 u32 newsid;
3064 int rc;
3065
3066 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3067 return -EOPNOTSUPP;
3068
3069 if (!value || !size)
3070 return -EACCES;
3071
3072 rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
3073 if (rc)
3074 return rc;
3075
3076 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3077 isec->sid = newsid;
3078 isec->initialized = 1;
3079 return 0;
3080}
3081
3082static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3083{
3084 const int len = sizeof(XATTR_NAME_SELINUX);
3085 if (buffer && len <= buffer_size)
3086 memcpy(buffer, XATTR_NAME_SELINUX, len);
3087 return len;
3088}
3089
3090static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3091{
3092 struct inode_security_struct *isec = inode->i_security;
3093 *secid = isec->sid;
3094}
3095
3096/* file security operations */
3097
3098static int selinux_revalidate_file_permission(struct file *file, int mask)
3099{
3100 const struct cred *cred = current_cred();
3101 struct inode *inode = file_inode(file);
3102
3103 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3104 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3105 mask |= MAY_APPEND;
3106
3107 return file_has_perm(cred, file,
3108 file_mask_to_av(inode->i_mode, mask));
3109}
3110
3111static int selinux_file_permission(struct file *file, int mask)
3112{
3113 struct inode *inode = file_inode(file);
3114 struct file_security_struct *fsec = file->f_security;
3115 struct inode_security_struct *isec = inode->i_security;
3116 u32 sid = current_sid();
3117
3118 if (!mask)
3119 /* No permission to check. Existence test. */
3120 return 0;
3121
3122 if (sid == fsec->sid && fsec->isid == isec->sid &&
3123 fsec->pseqno == avc_policy_seqno())
3124 /* No change since file_open check. */
3125 return 0;
3126
3127 return selinux_revalidate_file_permission(file, mask);
3128}
3129
3130static int selinux_file_alloc_security(struct file *file)
3131{
3132 return file_alloc_security(file);
3133}
3134
3135static void selinux_file_free_security(struct file *file)
3136{
3137 file_free_security(file);
3138}
3139
3140static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3141 unsigned long arg)
3142{
3143 const struct cred *cred = current_cred();
3144 int error = 0;
3145
3146 switch (cmd) {
3147 case FIONREAD:
3148 /* fall through */
3149 case FIBMAP:
3150 /* fall through */
3151 case FIGETBSZ:
3152 /* fall through */
3153 case FS_IOC_GETFLAGS:
3154 /* fall through */
3155 case FS_IOC_GETVERSION:
3156 error = file_has_perm(cred, file, FILE__GETATTR);
3157 break;
3158
3159 case FS_IOC_SETFLAGS:
3160 /* fall through */
3161 case FS_IOC_SETVERSION:
3162 error = file_has_perm(cred, file, FILE__SETATTR);
3163 break;
3164
3165 /* sys_ioctl() checks */
3166 case FIONBIO:
3167 /* fall through */
3168 case FIOASYNC:
3169 error = file_has_perm(cred, file, 0);
3170 break;
3171
3172 case KDSKBENT:
3173 case KDSKBSENT:
3174 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3175 SECURITY_CAP_AUDIT);
3176 break;
3177
3178 /* default case assumes that the command will go
3179 * to the file's ioctl() function.
3180 */
3181 default:
3182 error = file_has_perm(cred, file, FILE__IOCTL);
3183 }
3184 return error;
3185}
3186
3187static int default_noexec;
3188
3189static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3190{
3191 const struct cred *cred = current_cred();
3192 int rc = 0;
3193
3194 if (default_noexec &&
3195 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3196 /*
3197 * We are making executable an anonymous mapping or a
3198 * private file mapping that will also be writable.
3199 * This has an additional check.
3200 */
3201 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3202 if (rc)
3203 goto error;
3204 }
3205
3206 if (file) {
3207 /* read access is always possible with a mapping */
3208 u32 av = FILE__READ;
3209
3210 /* write access only matters if the mapping is shared */
3211 if (shared && (prot & PROT_WRITE))
3212 av |= FILE__WRITE;
3213
3214 if (prot & PROT_EXEC)
3215 av |= FILE__EXECUTE;
3216
3217 return file_has_perm(cred, file, av);
3218 }
3219
3220error:
3221 return rc;
3222}
3223
3224static int selinux_mmap_addr(unsigned long addr)
3225{
3226 int rc;
3227
3228 /* do DAC check on address space usage */
3229 rc = cap_mmap_addr(addr);
3230 if (rc)
3231 return rc;
3232
3233 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3234 u32 sid = current_sid();
3235 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3236 MEMPROTECT__MMAP_ZERO, NULL);
3237 }
3238
3239 return rc;
3240}
3241
3242static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3243 unsigned long prot, unsigned long flags)
3244{
3245 if (selinux_checkreqprot)
3246 prot = reqprot;
3247
3248 return file_map_prot_check(file, prot,
3249 (flags & MAP_TYPE) == MAP_SHARED);
3250}
3251
3252static int selinux_file_mprotect(struct vm_area_struct *vma,
3253 unsigned long reqprot,
3254 unsigned long prot)
3255{
3256 const struct cred *cred = current_cred();
3257
3258 if (selinux_checkreqprot)
3259 prot = reqprot;
3260
3261 if (default_noexec &&
3262 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3263 int rc = 0;
3264 if (vma->vm_start >= vma->vm_mm->start_brk &&
3265 vma->vm_end <= vma->vm_mm->brk) {
3266 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3267 } else if (!vma->vm_file &&
3268 vma->vm_start <= vma->vm_mm->start_stack &&
3269 vma->vm_end >= vma->vm_mm->start_stack) {
3270 rc = current_has_perm(current, PROCESS__EXECSTACK);
3271 } else if (vma->vm_file && vma->anon_vma) {
3272 /*
3273 * We are making executable a file mapping that has
3274 * had some COW done. Since pages might have been
3275 * written, check ability to execute the possibly
3276 * modified content. This typically should only
3277 * occur for text relocations.
3278 */
3279 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3280 }
3281 if (rc)
3282 return rc;
3283 }
3284
3285 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3286}
3287
3288static int selinux_file_lock(struct file *file, unsigned int cmd)
3289{
3290 const struct cred *cred = current_cred();
3291
3292 return file_has_perm(cred, file, FILE__LOCK);
3293}
3294
3295static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3296 unsigned long arg)
3297{
3298 const struct cred *cred = current_cred();
3299 int err = 0;
3300
3301 switch (cmd) {
3302 case F_SETFL:
3303 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3304 err = file_has_perm(cred, file, FILE__WRITE);
3305 break;
3306 }
3307 /* fall through */
3308 case F_SETOWN:
3309 case F_SETSIG:
3310 case F_GETFL:
3311 case F_GETOWN:
3312 case F_GETSIG:
3313 case F_GETOWNER_UIDS:
3314 /* Just check FD__USE permission */
3315 err = file_has_perm(cred, file, 0);
3316 break;
3317 case F_GETLK:
3318 case F_SETLK:
3319 case F_SETLKW:
3320 case F_OFD_GETLK:
3321 case F_OFD_SETLK:
3322 case F_OFD_SETLKW:
3323#if BITS_PER_LONG == 32
3324 case F_GETLK64:
3325 case F_SETLK64:
3326 case F_SETLKW64:
3327#endif
3328 err = file_has_perm(cred, file, FILE__LOCK);
3329 break;
3330 }
3331
3332 return err;
3333}
3334
3335static int selinux_file_set_fowner(struct file *file)
3336{
3337 struct file_security_struct *fsec;
3338
3339 fsec = file->f_security;
3340 fsec->fown_sid = current_sid();
3341
3342 return 0;
3343}
3344
3345static int selinux_file_send_sigiotask(struct task_struct *tsk,
3346 struct fown_struct *fown, int signum)
3347{
3348 struct file *file;
3349 u32 sid = task_sid(tsk);
3350 u32 perm;
3351 struct file_security_struct *fsec;
3352
3353 /* struct fown_struct is never outside the context of a struct file */
3354 file = container_of(fown, struct file, f_owner);
3355
3356 fsec = file->f_security;
3357
3358 if (!signum)
3359 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3360 else
3361 perm = signal_to_av(signum);
3362
3363 return avc_has_perm(fsec->fown_sid, sid,
3364 SECCLASS_PROCESS, perm, NULL);
3365}
3366
3367static int selinux_file_receive(struct file *file)
3368{
3369 const struct cred *cred = current_cred();
3370
3371 return file_has_perm(cred, file, file_to_av(file));
3372}
3373
3374static int selinux_file_open(struct file *file, const struct cred *cred)
3375{
3376 struct file_security_struct *fsec;
3377 struct inode_security_struct *isec;
3378
3379 fsec = file->f_security;
3380 isec = file_inode(file)->i_security;
3381 /*
3382 * Save inode label and policy sequence number
3383 * at open-time so that selinux_file_permission
3384 * can determine whether revalidation is necessary.
3385 * Task label is already saved in the file security
3386 * struct as its SID.
3387 */
3388 fsec->isid = isec->sid;
3389 fsec->pseqno = avc_policy_seqno();
3390 /*
3391 * Since the inode label or policy seqno may have changed
3392 * between the selinux_inode_permission check and the saving
3393 * of state above, recheck that access is still permitted.
3394 * Otherwise, access might never be revalidated against the
3395 * new inode label or new policy.
3396 * This check is not redundant - do not remove.
3397 */
3398 return file_path_has_perm(cred, file, open_file_to_av(file));
3399}
3400
3401/* task security operations */
3402
3403static int selinux_task_create(unsigned long clone_flags)
3404{
3405 return current_has_perm(current, PROCESS__FORK);
3406}
3407
3408/*
3409 * allocate the SELinux part of blank credentials
3410 */
3411static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3412{
3413 struct task_security_struct *tsec;
3414
3415 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3416 if (!tsec)
3417 return -ENOMEM;
3418
3419 cred->security = tsec;
3420 return 0;
3421}
3422
3423/*
3424 * detach and free the LSM part of a set of credentials
3425 */
3426static void selinux_cred_free(struct cred *cred)
3427{
3428 struct task_security_struct *tsec = cred->security;
3429
3430 /*
3431 * cred->security == NULL if security_cred_alloc_blank() or
3432 * security_prepare_creds() returned an error.
3433 */
3434 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3435 cred->security = (void *) 0x7UL;
3436 kfree(tsec);
3437}
3438
3439/*
3440 * prepare a new set of credentials for modification
3441 */
3442static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3443 gfp_t gfp)
3444{
3445 const struct task_security_struct *old_tsec;
3446 struct task_security_struct *tsec;
3447
3448 old_tsec = old->security;
3449
3450 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3451 if (!tsec)
3452 return -ENOMEM;
3453
3454 new->security = tsec;
3455 return 0;
3456}
3457
3458/*
3459 * transfer the SELinux data to a blank set of creds
3460 */
3461static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3462{
3463 const struct task_security_struct *old_tsec = old->security;
3464 struct task_security_struct *tsec = new->security;
3465
3466 *tsec = *old_tsec;
3467}
3468
3469/*
3470 * set the security data for a kernel service
3471 * - all the creation contexts are set to unlabelled
3472 */
3473static int selinux_kernel_act_as(struct cred *new, u32 secid)
3474{
3475 struct task_security_struct *tsec = new->security;
3476 u32 sid = current_sid();
3477 int ret;
3478
3479 ret = avc_has_perm(sid, secid,
3480 SECCLASS_KERNEL_SERVICE,
3481 KERNEL_SERVICE__USE_AS_OVERRIDE,
3482 NULL);
3483 if (ret == 0) {
3484 tsec->sid = secid;
3485 tsec->create_sid = 0;
3486 tsec->keycreate_sid = 0;
3487 tsec->sockcreate_sid = 0;
3488 }
3489 return ret;
3490}
3491
3492/*
3493 * set the file creation context in a security record to the same as the
3494 * objective context of the specified inode
3495 */
3496static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3497{
3498 struct inode_security_struct *isec = inode->i_security;
3499 struct task_security_struct *tsec = new->security;
3500 u32 sid = current_sid();
3501 int ret;
3502
3503 ret = avc_has_perm(sid, isec->sid,
3504 SECCLASS_KERNEL_SERVICE,
3505 KERNEL_SERVICE__CREATE_FILES_AS,
3506 NULL);
3507
3508 if (ret == 0)
3509 tsec->create_sid = isec->sid;
3510 return ret;
3511}
3512
3513static int selinux_kernel_module_request(char *kmod_name)
3514{
3515 u32 sid;
3516 struct common_audit_data ad;
3517
3518 sid = task_sid(current);
3519
3520 ad.type = LSM_AUDIT_DATA_KMOD;
3521 ad.u.kmod_name = kmod_name;
3522
3523 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3524 SYSTEM__MODULE_REQUEST, &ad);
3525}
3526
3527static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3528{
3529 return current_has_perm(p, PROCESS__SETPGID);
3530}
3531
3532static int selinux_task_getpgid(struct task_struct *p)
3533{
3534 return current_has_perm(p, PROCESS__GETPGID);
3535}
3536
3537static int selinux_task_getsid(struct task_struct *p)
3538{
3539 return current_has_perm(p, PROCESS__GETSESSION);
3540}
3541
3542static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3543{
3544 *secid = task_sid(p);
3545}
3546
3547static int selinux_task_setnice(struct task_struct *p, int nice)
3548{
3549 int rc;
3550
3551 rc = cap_task_setnice(p, nice);
3552 if (rc)
3553 return rc;
3554
3555 return current_has_perm(p, PROCESS__SETSCHED);
3556}
3557
3558static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3559{
3560 int rc;
3561
3562 rc = cap_task_setioprio(p, ioprio);
3563 if (rc)
3564 return rc;
3565
3566 return current_has_perm(p, PROCESS__SETSCHED);
3567}
3568
3569static int selinux_task_getioprio(struct task_struct *p)
3570{
3571 return current_has_perm(p, PROCESS__GETSCHED);
3572}
3573
3574static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3575 struct rlimit *new_rlim)
3576{
3577 struct rlimit *old_rlim = p->signal->rlim + resource;
3578
3579 /* Control the ability to change the hard limit (whether
3580 lowering or raising it), so that the hard limit can
3581 later be used as a safe reset point for the soft limit
3582 upon context transitions. See selinux_bprm_committing_creds. */
3583 if (old_rlim->rlim_max != new_rlim->rlim_max)
3584 return current_has_perm(p, PROCESS__SETRLIMIT);
3585
3586 return 0;
3587}
3588
3589static int selinux_task_setscheduler(struct task_struct *p)
3590{
3591 int rc;
3592
3593 rc = cap_task_setscheduler(p);
3594 if (rc)
3595 return rc;
3596
3597 return current_has_perm(p, PROCESS__SETSCHED);
3598}
3599
3600static int selinux_task_getscheduler(struct task_struct *p)
3601{
3602 return current_has_perm(p, PROCESS__GETSCHED);
3603}
3604
3605static int selinux_task_movememory(struct task_struct *p)
3606{
3607 return current_has_perm(p, PROCESS__SETSCHED);
3608}
3609
3610static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3611 int sig, u32 secid)
3612{
3613 u32 perm;
3614 int rc;
3615
3616 if (!sig)
3617 perm = PROCESS__SIGNULL; /* null signal; existence test */
3618 else
3619 perm = signal_to_av(sig);
3620 if (secid)
3621 rc = avc_has_perm(secid, task_sid(p),
3622 SECCLASS_PROCESS, perm, NULL);
3623 else
3624 rc = current_has_perm(p, perm);
3625 return rc;
3626}
3627
3628static int selinux_task_wait(struct task_struct *p)
3629{
3630 return task_has_perm(p, current, PROCESS__SIGCHLD);
3631}
3632
3633static void selinux_task_to_inode(struct task_struct *p,
3634 struct inode *inode)
3635{
3636 struct inode_security_struct *isec = inode->i_security;
3637 u32 sid = task_sid(p);
3638
3639 isec->sid = sid;
3640 isec->initialized = 1;
3641}
3642
3643/* Returns error only if unable to parse addresses */
3644static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3645 struct common_audit_data *ad, u8 *proto)
3646{
3647 int offset, ihlen, ret = -EINVAL;
3648 struct iphdr _iph, *ih;
3649
3650 offset = skb_network_offset(skb);
3651 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3652 if (ih == NULL)
3653 goto out;
3654
3655 ihlen = ih->ihl * 4;
3656 if (ihlen < sizeof(_iph))
3657 goto out;
3658
3659 ad->u.net->v4info.saddr = ih->saddr;
3660 ad->u.net->v4info.daddr = ih->daddr;
3661 ret = 0;
3662
3663 if (proto)
3664 *proto = ih->protocol;
3665
3666 switch (ih->protocol) {
3667 case IPPROTO_TCP: {
3668 struct tcphdr _tcph, *th;
3669
3670 if (ntohs(ih->frag_off) & IP_OFFSET)
3671 break;
3672
3673 offset += ihlen;
3674 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3675 if (th == NULL)
3676 break;
3677
3678 ad->u.net->sport = th->source;
3679 ad->u.net->dport = th->dest;
3680 break;
3681 }
3682
3683 case IPPROTO_UDP: {
3684 struct udphdr _udph, *uh;
3685
3686 if (ntohs(ih->frag_off) & IP_OFFSET)
3687 break;
3688
3689 offset += ihlen;
3690 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3691 if (uh == NULL)
3692 break;
3693
3694 ad->u.net->sport = uh->source;
3695 ad->u.net->dport = uh->dest;
3696 break;
3697 }
3698
3699 case IPPROTO_DCCP: {
3700 struct dccp_hdr _dccph, *dh;
3701
3702 if (ntohs(ih->frag_off) & IP_OFFSET)
3703 break;
3704
3705 offset += ihlen;
3706 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3707 if (dh == NULL)
3708 break;
3709
3710 ad->u.net->sport = dh->dccph_sport;
3711 ad->u.net->dport = dh->dccph_dport;
3712 break;
3713 }
3714
3715 default:
3716 break;
3717 }
3718out:
3719 return ret;
3720}
3721
3722#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3723
3724/* Returns error only if unable to parse addresses */
3725static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3726 struct common_audit_data *ad, u8 *proto)
3727{
3728 u8 nexthdr;
3729 int ret = -EINVAL, offset;
3730 struct ipv6hdr _ipv6h, *ip6;
3731 __be16 frag_off;
3732
3733 offset = skb_network_offset(skb);
3734 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3735 if (ip6 == NULL)
3736 goto out;
3737
3738 ad->u.net->v6info.saddr = ip6->saddr;
3739 ad->u.net->v6info.daddr = ip6->daddr;
3740 ret = 0;
3741
3742 nexthdr = ip6->nexthdr;
3743 offset += sizeof(_ipv6h);
3744 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3745 if (offset < 0)
3746 goto out;
3747
3748 if (proto)
3749 *proto = nexthdr;
3750
3751 switch (nexthdr) {
3752 case IPPROTO_TCP: {
3753 struct tcphdr _tcph, *th;
3754
3755 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3756 if (th == NULL)
3757 break;
3758
3759 ad->u.net->sport = th->source;
3760 ad->u.net->dport = th->dest;
3761 break;
3762 }
3763
3764 case IPPROTO_UDP: {
3765 struct udphdr _udph, *uh;
3766
3767 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3768 if (uh == NULL)
3769 break;
3770
3771 ad->u.net->sport = uh->source;
3772 ad->u.net->dport = uh->dest;
3773 break;
3774 }
3775
3776 case IPPROTO_DCCP: {
3777 struct dccp_hdr _dccph, *dh;
3778
3779 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3780 if (dh == NULL)
3781 break;
3782
3783 ad->u.net->sport = dh->dccph_sport;
3784 ad->u.net->dport = dh->dccph_dport;
3785 break;
3786 }
3787
3788 /* includes fragments */
3789 default:
3790 break;
3791 }
3792out:
3793 return ret;
3794}
3795
3796#endif /* IPV6 */
3797
3798static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3799 char **_addrp, int src, u8 *proto)
3800{
3801 char *addrp;
3802 int ret;
3803
3804 switch (ad->u.net->family) {
3805 case PF_INET:
3806 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3807 if (ret)
3808 goto parse_error;
3809 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3810 &ad->u.net->v4info.daddr);
3811 goto okay;
3812
3813#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3814 case PF_INET6:
3815 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3816 if (ret)
3817 goto parse_error;
3818 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3819 &ad->u.net->v6info.daddr);
3820 goto okay;
3821#endif /* IPV6 */
3822 default:
3823 addrp = NULL;
3824 goto okay;
3825 }
3826
3827parse_error:
3828 printk(KERN_WARNING
3829 "SELinux: failure in selinux_parse_skb(),"
3830 " unable to parse packet\n");
3831 return ret;
3832
3833okay:
3834 if (_addrp)
3835 *_addrp = addrp;
3836 return 0;
3837}
3838
3839/**
3840 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3841 * @skb: the packet
3842 * @family: protocol family
3843 * @sid: the packet's peer label SID
3844 *
3845 * Description:
3846 * Check the various different forms of network peer labeling and determine
3847 * the peer label/SID for the packet; most of the magic actually occurs in
3848 * the security server function security_net_peersid_cmp(). The function
3849 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3850 * or -EACCES if @sid is invalid due to inconsistencies with the different
3851 * peer labels.
3852 *
3853 */
3854static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3855{
3856 int err;
3857 u32 xfrm_sid;
3858 u32 nlbl_sid;
3859 u32 nlbl_type;
3860
3861 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3862 if (unlikely(err))
3863 return -EACCES;
3864 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3865 if (unlikely(err))
3866 return -EACCES;
3867
3868 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3869 if (unlikely(err)) {
3870 printk(KERN_WARNING
3871 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3872 " unable to determine packet's peer label\n");
3873 return -EACCES;
3874 }
3875
3876 return 0;
3877}
3878
3879/**
3880 * selinux_conn_sid - Determine the child socket label for a connection
3881 * @sk_sid: the parent socket's SID
3882 * @skb_sid: the packet's SID
3883 * @conn_sid: the resulting connection SID
3884 *
3885 * If @skb_sid is valid then the user:role:type information from @sk_sid is
3886 * combined with the MLS information from @skb_sid in order to create
3887 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
3888 * of @sk_sid. Returns zero on success, negative values on failure.
3889 *
3890 */
3891static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
3892{
3893 int err = 0;
3894
3895 if (skb_sid != SECSID_NULL)
3896 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
3897 else
3898 *conn_sid = sk_sid;
3899
3900 return err;
3901}
3902
3903/* socket security operations */
3904
3905static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3906 u16 secclass, u32 *socksid)
3907{
3908 if (tsec->sockcreate_sid > SECSID_NULL) {
3909 *socksid = tsec->sockcreate_sid;
3910 return 0;
3911 }
3912
3913 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3914 socksid);
3915}
3916
3917static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3918{
3919 struct sk_security_struct *sksec = sk->sk_security;
3920 struct common_audit_data ad;
3921 struct lsm_network_audit net = {0,};
3922 u32 tsid = task_sid(task);
3923
3924 if (sksec->sid == SECINITSID_KERNEL)
3925 return 0;
3926
3927 ad.type = LSM_AUDIT_DATA_NET;
3928 ad.u.net = &net;
3929 ad.u.net->sk = sk;
3930
3931 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3932}
3933
3934static int selinux_socket_create(int family, int type,
3935 int protocol, int kern)
3936{
3937 const struct task_security_struct *tsec = current_security();
3938 u32 newsid;
3939 u16 secclass;
3940 int rc;
3941
3942 if (kern)
3943 return 0;
3944
3945 secclass = socket_type_to_security_class(family, type, protocol);
3946 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3947 if (rc)
3948 return rc;
3949
3950 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3951}
3952
3953static int selinux_socket_post_create(struct socket *sock, int family,
3954 int type, int protocol, int kern)
3955{
3956 const struct task_security_struct *tsec = current_security();
3957 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3958 struct sk_security_struct *sksec;
3959 int err = 0;
3960
3961 isec->sclass = socket_type_to_security_class(family, type, protocol);
3962
3963 if (kern)
3964 isec->sid = SECINITSID_KERNEL;
3965 else {
3966 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3967 if (err)
3968 return err;
3969 }
3970
3971 isec->initialized = 1;
3972
3973 if (sock->sk) {
3974 sksec = sock->sk->sk_security;
3975 sksec->sid = isec->sid;
3976 sksec->sclass = isec->sclass;
3977 err = selinux_netlbl_socket_post_create(sock->sk, family);
3978 }
3979
3980 return err;
3981}
3982
3983/* Range of port numbers used to automatically bind.
3984 Need to determine whether we should perform a name_bind
3985 permission check between the socket and the port number. */
3986
3987static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3988{
3989 struct sock *sk = sock->sk;
3990 u16 family;
3991 int err;
3992
3993 err = sock_has_perm(current, sk, SOCKET__BIND);
3994 if (err)
3995 goto out;
3996
3997 /*
3998 * If PF_INET or PF_INET6, check name_bind permission for the port.
3999 * Multiple address binding for SCTP is not supported yet: we just
4000 * check the first address now.
4001 */
4002 family = sk->sk_family;
4003 if (family == PF_INET || family == PF_INET6) {
4004 char *addrp;
4005 struct sk_security_struct *sksec = sk->sk_security;
4006 struct common_audit_data ad;
4007 struct lsm_network_audit net = {0,};
4008 struct sockaddr_in *addr4 = NULL;
4009 struct sockaddr_in6 *addr6 = NULL;
4010 unsigned short snum;
4011 u32 sid, node_perm;
4012
4013 if (family == PF_INET) {
4014 addr4 = (struct sockaddr_in *)address;
4015 snum = ntohs(addr4->sin_port);
4016 addrp = (char *)&addr4->sin_addr.s_addr;
4017 } else {
4018 addr6 = (struct sockaddr_in6 *)address;
4019 snum = ntohs(addr6->sin6_port);
4020 addrp = (char *)&addr6->sin6_addr.s6_addr;
4021 }
4022
4023 if (snum) {
4024 int low, high;
4025
4026 inet_get_local_port_range(sock_net(sk), &low, &high);
4027
4028 if (snum < max(PROT_SOCK, low) || snum > high) {
4029 err = sel_netport_sid(sk->sk_protocol,
4030 snum, &sid);
4031 if (err)
4032 goto out;
4033 ad.type = LSM_AUDIT_DATA_NET;
4034 ad.u.net = &net;
4035 ad.u.net->sport = htons(snum);
4036 ad.u.net->family = family;
4037 err = avc_has_perm(sksec->sid, sid,
4038 sksec->sclass,
4039 SOCKET__NAME_BIND, &ad);
4040 if (err)
4041 goto out;
4042 }
4043 }
4044
4045 switch (sksec->sclass) {
4046 case SECCLASS_TCP_SOCKET:
4047 node_perm = TCP_SOCKET__NODE_BIND;
4048 break;
4049
4050 case SECCLASS_UDP_SOCKET:
4051 node_perm = UDP_SOCKET__NODE_BIND;
4052 break;
4053
4054 case SECCLASS_DCCP_SOCKET:
4055 node_perm = DCCP_SOCKET__NODE_BIND;
4056 break;
4057
4058 default:
4059 node_perm = RAWIP_SOCKET__NODE_BIND;
4060 break;
4061 }
4062
4063 err = sel_netnode_sid(addrp, family, &sid);
4064 if (err)
4065 goto out;
4066
4067 ad.type = LSM_AUDIT_DATA_NET;
4068 ad.u.net = &net;
4069 ad.u.net->sport = htons(snum);
4070 ad.u.net->family = family;
4071
4072 if (family == PF_INET)
4073 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4074 else
4075 ad.u.net->v6info.saddr = addr6->sin6_addr;
4076
4077 err = avc_has_perm(sksec->sid, sid,
4078 sksec->sclass, node_perm, &ad);
4079 if (err)
4080 goto out;
4081 }
4082out:
4083 return err;
4084}
4085
4086static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4087{
4088 struct sock *sk = sock->sk;
4089 struct sk_security_struct *sksec = sk->sk_security;
4090 int err;
4091
4092 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4093 if (err)
4094 return err;
4095
4096 /*
4097 * If a TCP or DCCP socket, check name_connect permission for the port.
4098 */
4099 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4100 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4101 struct common_audit_data ad;
4102 struct lsm_network_audit net = {0,};
4103 struct sockaddr_in *addr4 = NULL;
4104 struct sockaddr_in6 *addr6 = NULL;
4105 unsigned short snum;
4106 u32 sid, perm;
4107
4108 if (sk->sk_family == PF_INET) {
4109 addr4 = (struct sockaddr_in *)address;
4110 if (addrlen < sizeof(struct sockaddr_in))
4111 return -EINVAL;
4112 snum = ntohs(addr4->sin_port);
4113 } else {
4114 addr6 = (struct sockaddr_in6 *)address;
4115 if (addrlen < SIN6_LEN_RFC2133)
4116 return -EINVAL;
4117 snum = ntohs(addr6->sin6_port);
4118 }
4119
4120 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4121 if (err)
4122 goto out;
4123
4124 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4125 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4126
4127 ad.type = LSM_AUDIT_DATA_NET;
4128 ad.u.net = &net;
4129 ad.u.net->dport = htons(snum);
4130 ad.u.net->family = sk->sk_family;
4131 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4132 if (err)
4133 goto out;
4134 }
4135
4136 err = selinux_netlbl_socket_connect(sk, address);
4137
4138out:
4139 return err;
4140}
4141
4142static int selinux_socket_listen(struct socket *sock, int backlog)
4143{
4144 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4145}
4146
4147static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4148{
4149 int err;
4150 struct inode_security_struct *isec;
4151 struct inode_security_struct *newisec;
4152
4153 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4154 if (err)
4155 return err;
4156
4157 newisec = SOCK_INODE(newsock)->i_security;
4158
4159 isec = SOCK_INODE(sock)->i_security;
4160 newisec->sclass = isec->sclass;
4161 newisec->sid = isec->sid;
4162 newisec->initialized = 1;
4163
4164 return 0;
4165}
4166
4167static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4168 int size)
4169{
4170 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4171}
4172
4173static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4174 int size, int flags)
4175{
4176 return sock_has_perm(current, sock->sk, SOCKET__READ);
4177}
4178
4179static int selinux_socket_getsockname(struct socket *sock)
4180{
4181 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4182}
4183
4184static int selinux_socket_getpeername(struct socket *sock)
4185{
4186 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4187}
4188
4189static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4190{
4191 int err;
4192
4193 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4194 if (err)
4195 return err;
4196
4197 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4198}
4199
4200static int selinux_socket_getsockopt(struct socket *sock, int level,
4201 int optname)
4202{
4203 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4204}
4205
4206static int selinux_socket_shutdown(struct socket *sock, int how)
4207{
4208 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4209}
4210
4211static int selinux_socket_unix_stream_connect(struct sock *sock,
4212 struct sock *other,
4213 struct sock *newsk)
4214{
4215 struct sk_security_struct *sksec_sock = sock->sk_security;
4216 struct sk_security_struct *sksec_other = other->sk_security;
4217 struct sk_security_struct *sksec_new = newsk->sk_security;
4218 struct common_audit_data ad;
4219 struct lsm_network_audit net = {0,};
4220 int err;
4221
4222 ad.type = LSM_AUDIT_DATA_NET;
4223 ad.u.net = &net;
4224 ad.u.net->sk = other;
4225
4226 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4227 sksec_other->sclass,
4228 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4229 if (err)
4230 return err;
4231
4232 /* server child socket */
4233 sksec_new->peer_sid = sksec_sock->sid;
4234 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4235 &sksec_new->sid);
4236 if (err)
4237 return err;
4238
4239 /* connecting socket */
4240 sksec_sock->peer_sid = sksec_new->sid;
4241
4242 return 0;
4243}
4244
4245static int selinux_socket_unix_may_send(struct socket *sock,
4246 struct socket *other)
4247{
4248 struct sk_security_struct *ssec = sock->sk->sk_security;
4249 struct sk_security_struct *osec = other->sk->sk_security;
4250 struct common_audit_data ad;
4251 struct lsm_network_audit net = {0,};
4252
4253 ad.type = LSM_AUDIT_DATA_NET;
4254 ad.u.net = &net;
4255 ad.u.net->sk = other->sk;
4256
4257 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4258 &ad);
4259}
4260
4261static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4262 u32 peer_sid,
4263 struct common_audit_data *ad)
4264{
4265 int err;
4266 u32 if_sid;
4267 u32 node_sid;
4268
4269 err = sel_netif_sid(ifindex, &if_sid);
4270 if (err)
4271 return err;
4272 err = avc_has_perm(peer_sid, if_sid,
4273 SECCLASS_NETIF, NETIF__INGRESS, ad);
4274 if (err)
4275 return err;
4276
4277 err = sel_netnode_sid(addrp, family, &node_sid);
4278 if (err)
4279 return err;
4280 return avc_has_perm(peer_sid, node_sid,
4281 SECCLASS_NODE, NODE__RECVFROM, ad);
4282}
4283
4284static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4285 u16 family)
4286{
4287 int err = 0;
4288 struct sk_security_struct *sksec = sk->sk_security;
4289 u32 sk_sid = sksec->sid;
4290 struct common_audit_data ad;
4291 struct lsm_network_audit net = {0,};
4292 char *addrp;
4293
4294 ad.type = LSM_AUDIT_DATA_NET;
4295 ad.u.net = &net;
4296 ad.u.net->netif = skb->skb_iif;
4297 ad.u.net->family = family;
4298 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4299 if (err)
4300 return err;
4301
4302 if (selinux_secmark_enabled()) {
4303 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4304 PACKET__RECV, &ad);
4305 if (err)
4306 return err;
4307 }
4308
4309 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4310 if (err)
4311 return err;
4312 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4313
4314 return err;
4315}
4316
4317static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4318{
4319 int err;
4320 struct sk_security_struct *sksec = sk->sk_security;
4321 u16 family = sk->sk_family;
4322 u32 sk_sid = sksec->sid;
4323 struct common_audit_data ad;
4324 struct lsm_network_audit net = {0,};
4325 char *addrp;
4326 u8 secmark_active;
4327 u8 peerlbl_active;
4328
4329 if (family != PF_INET && family != PF_INET6)
4330 return 0;
4331
4332 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4333 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4334 family = PF_INET;
4335
4336 /* If any sort of compatibility mode is enabled then handoff processing
4337 * to the selinux_sock_rcv_skb_compat() function to deal with the
4338 * special handling. We do this in an attempt to keep this function
4339 * as fast and as clean as possible. */
4340 if (!selinux_policycap_netpeer)
4341 return selinux_sock_rcv_skb_compat(sk, skb, family);
4342
4343 secmark_active = selinux_secmark_enabled();
4344 peerlbl_active = selinux_peerlbl_enabled();
4345 if (!secmark_active && !peerlbl_active)
4346 return 0;
4347
4348 ad.type = LSM_AUDIT_DATA_NET;
4349 ad.u.net = &net;
4350 ad.u.net->netif = skb->skb_iif;
4351 ad.u.net->family = family;
4352 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4353 if (err)
4354 return err;
4355
4356 if (peerlbl_active) {
4357 u32 peer_sid;
4358
4359 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4360 if (err)
4361 return err;
4362 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4363 peer_sid, &ad);
4364 if (err) {
4365 selinux_netlbl_err(skb, err, 0);
4366 return err;
4367 }
4368 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4369 PEER__RECV, &ad);
4370 if (err) {
4371 selinux_netlbl_err(skb, err, 0);
4372 return err;
4373 }
4374 }
4375
4376 if (secmark_active) {
4377 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4378 PACKET__RECV, &ad);
4379 if (err)
4380 return err;
4381 }
4382
4383 return err;
4384}
4385
4386static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4387 int __user *optlen, unsigned len)
4388{
4389 int err = 0;
4390 char *scontext;
4391 u32 scontext_len;
4392 struct sk_security_struct *sksec = sock->sk->sk_security;
4393 u32 peer_sid = SECSID_NULL;
4394
4395 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4396 sksec->sclass == SECCLASS_TCP_SOCKET)
4397 peer_sid = sksec->peer_sid;
4398 if (peer_sid == SECSID_NULL)
4399 return -ENOPROTOOPT;
4400
4401 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4402 if (err)
4403 return err;
4404
4405 if (scontext_len > len) {
4406 err = -ERANGE;
4407 goto out_len;
4408 }
4409
4410 if (copy_to_user(optval, scontext, scontext_len))
4411 err = -EFAULT;
4412
4413out_len:
4414 if (put_user(scontext_len, optlen))
4415 err = -EFAULT;
4416 kfree(scontext);
4417 return err;
4418}
4419
4420static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4421{
4422 u32 peer_secid = SECSID_NULL;
4423 u16 family;
4424
4425 if (skb && skb->protocol == htons(ETH_P_IP))
4426 family = PF_INET;
4427 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4428 family = PF_INET6;
4429 else if (sock)
4430 family = sock->sk->sk_family;
4431 else
4432 goto out;
4433
4434 if (sock && family == PF_UNIX)
4435 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4436 else if (skb)
4437 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4438
4439out:
4440 *secid = peer_secid;
4441 if (peer_secid == SECSID_NULL)
4442 return -EINVAL;
4443 return 0;
4444}
4445
4446static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4447{
4448 struct sk_security_struct *sksec;
4449
4450 sksec = kzalloc(sizeof(*sksec), priority);
4451 if (!sksec)
4452 return -ENOMEM;
4453
4454 sksec->peer_sid = SECINITSID_UNLABELED;
4455 sksec->sid = SECINITSID_UNLABELED;
4456 selinux_netlbl_sk_security_reset(sksec);
4457 sk->sk_security = sksec;
4458
4459 return 0;
4460}
4461
4462static void selinux_sk_free_security(struct sock *sk)
4463{
4464 struct sk_security_struct *sksec = sk->sk_security;
4465
4466 sk->sk_security = NULL;
4467 selinux_netlbl_sk_security_free(sksec);
4468 kfree(sksec);
4469}
4470
4471static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4472{
4473 struct sk_security_struct *sksec = sk->sk_security;
4474 struct sk_security_struct *newsksec = newsk->sk_security;
4475
4476 newsksec->sid = sksec->sid;
4477 newsksec->peer_sid = sksec->peer_sid;
4478 newsksec->sclass = sksec->sclass;
4479
4480 selinux_netlbl_sk_security_reset(newsksec);
4481}
4482
4483static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4484{
4485 if (!sk)
4486 *secid = SECINITSID_ANY_SOCKET;
4487 else {
4488 struct sk_security_struct *sksec = sk->sk_security;
4489
4490 *secid = sksec->sid;
4491 }
4492}
4493
4494static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4495{
4496 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4497 struct sk_security_struct *sksec = sk->sk_security;
4498
4499 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4500 sk->sk_family == PF_UNIX)
4501 isec->sid = sksec->sid;
4502 sksec->sclass = isec->sclass;
4503}
4504
4505static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4506 struct request_sock *req)
4507{
4508 struct sk_security_struct *sksec = sk->sk_security;
4509 int err;
4510 u16 family = req->rsk_ops->family;
4511 u32 connsid;
4512 u32 peersid;
4513
4514 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4515 if (err)
4516 return err;
4517 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4518 if (err)
4519 return err;
4520 req->secid = connsid;
4521 req->peer_secid = peersid;
4522
4523 return selinux_netlbl_inet_conn_request(req, family);
4524}
4525
4526static void selinux_inet_csk_clone(struct sock *newsk,
4527 const struct request_sock *req)
4528{
4529 struct sk_security_struct *newsksec = newsk->sk_security;
4530
4531 newsksec->sid = req->secid;
4532 newsksec->peer_sid = req->peer_secid;
4533 /* NOTE: Ideally, we should also get the isec->sid for the
4534 new socket in sync, but we don't have the isec available yet.
4535 So we will wait until sock_graft to do it, by which
4536 time it will have been created and available. */
4537
4538 /* We don't need to take any sort of lock here as we are the only
4539 * thread with access to newsksec */
4540 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4541}
4542
4543static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4544{
4545 u16 family = sk->sk_family;
4546 struct sk_security_struct *sksec = sk->sk_security;
4547
4548 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4549 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4550 family = PF_INET;
4551
4552 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4553}
4554
4555static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4556{
4557 skb_set_owner_w(skb, sk);
4558}
4559
4560static int selinux_secmark_relabel_packet(u32 sid)
4561{
4562 const struct task_security_struct *__tsec;
4563 u32 tsid;
4564
4565 __tsec = current_security();
4566 tsid = __tsec->sid;
4567
4568 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4569}
4570
4571static void selinux_secmark_refcount_inc(void)
4572{
4573 atomic_inc(&selinux_secmark_refcount);
4574}
4575
4576static void selinux_secmark_refcount_dec(void)
4577{
4578 atomic_dec(&selinux_secmark_refcount);
4579}
4580
4581static void selinux_req_classify_flow(const struct request_sock *req,
4582 struct flowi *fl)
4583{
4584 fl->flowi_secid = req->secid;
4585}
4586
4587static int selinux_tun_dev_alloc_security(void **security)
4588{
4589 struct tun_security_struct *tunsec;
4590
4591 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4592 if (!tunsec)
4593 return -ENOMEM;
4594 tunsec->sid = current_sid();
4595
4596 *security = tunsec;
4597 return 0;
4598}
4599
4600static void selinux_tun_dev_free_security(void *security)
4601{
4602 kfree(security);
4603}
4604
4605static int selinux_tun_dev_create(void)
4606{
4607 u32 sid = current_sid();
4608
4609 /* we aren't taking into account the "sockcreate" SID since the socket
4610 * that is being created here is not a socket in the traditional sense,
4611 * instead it is a private sock, accessible only to the kernel, and
4612 * representing a wide range of network traffic spanning multiple
4613 * connections unlike traditional sockets - check the TUN driver to
4614 * get a better understanding of why this socket is special */
4615
4616 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4617 NULL);
4618}
4619
4620static int selinux_tun_dev_attach_queue(void *security)
4621{
4622 struct tun_security_struct *tunsec = security;
4623
4624 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4625 TUN_SOCKET__ATTACH_QUEUE, NULL);
4626}
4627
4628static int selinux_tun_dev_attach(struct sock *sk, void *security)
4629{
4630 struct tun_security_struct *tunsec = security;
4631 struct sk_security_struct *sksec = sk->sk_security;
4632
4633 /* we don't currently perform any NetLabel based labeling here and it
4634 * isn't clear that we would want to do so anyway; while we could apply
4635 * labeling without the support of the TUN user the resulting labeled
4636 * traffic from the other end of the connection would almost certainly
4637 * cause confusion to the TUN user that had no idea network labeling
4638 * protocols were being used */
4639
4640 sksec->sid = tunsec->sid;
4641 sksec->sclass = SECCLASS_TUN_SOCKET;
4642
4643 return 0;
4644}
4645
4646static int selinux_tun_dev_open(void *security)
4647{
4648 struct tun_security_struct *tunsec = security;
4649 u32 sid = current_sid();
4650 int err;
4651
4652 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4653 TUN_SOCKET__RELABELFROM, NULL);
4654 if (err)
4655 return err;
4656 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4657 TUN_SOCKET__RELABELTO, NULL);
4658 if (err)
4659 return err;
4660 tunsec->sid = sid;
4661
4662 return 0;
4663}
4664
4665static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4666{
4667 int err = 0;
4668 u32 perm;
4669 struct nlmsghdr *nlh;
4670 struct sk_security_struct *sksec = sk->sk_security;
4671
4672 if (skb->len < NLMSG_HDRLEN) {
4673 err = -EINVAL;
4674 goto out;
4675 }
4676 nlh = nlmsg_hdr(skb);
4677
4678 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4679 if (err) {
4680 if (err == -EINVAL) {
4681 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4682 "SELinux: unrecognized netlink message"
4683 " type=%hu for sclass=%hu\n",
4684 nlh->nlmsg_type, sksec->sclass);
4685 if (!selinux_enforcing || security_get_allow_unknown())
4686 err = 0;
4687 }
4688
4689 /* Ignore */
4690 if (err == -ENOENT)
4691 err = 0;
4692 goto out;
4693 }
4694
4695 err = sock_has_perm(current, sk, perm);
4696out:
4697 return err;
4698}
4699
4700#ifdef CONFIG_NETFILTER
4701
4702static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4703 u16 family)
4704{
4705 int err;
4706 char *addrp;
4707 u32 peer_sid;
4708 struct common_audit_data ad;
4709 struct lsm_network_audit net = {0,};
4710 u8 secmark_active;
4711 u8 netlbl_active;
4712 u8 peerlbl_active;
4713
4714 if (!selinux_policycap_netpeer)
4715 return NF_ACCEPT;
4716
4717 secmark_active = selinux_secmark_enabled();
4718 netlbl_active = netlbl_enabled();
4719 peerlbl_active = selinux_peerlbl_enabled();
4720 if (!secmark_active && !peerlbl_active)
4721 return NF_ACCEPT;
4722
4723 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4724 return NF_DROP;
4725
4726 ad.type = LSM_AUDIT_DATA_NET;
4727 ad.u.net = &net;
4728 ad.u.net->netif = ifindex;
4729 ad.u.net->family = family;
4730 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4731 return NF_DROP;
4732
4733 if (peerlbl_active) {
4734 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4735 peer_sid, &ad);
4736 if (err) {
4737 selinux_netlbl_err(skb, err, 1);
4738 return NF_DROP;
4739 }
4740 }
4741
4742 if (secmark_active)
4743 if (avc_has_perm(peer_sid, skb->secmark,
4744 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4745 return NF_DROP;
4746
4747 if (netlbl_active)
4748 /* we do this in the FORWARD path and not the POST_ROUTING
4749 * path because we want to make sure we apply the necessary
4750 * labeling before IPsec is applied so we can leverage AH
4751 * protection */
4752 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4753 return NF_DROP;
4754
4755 return NF_ACCEPT;
4756}
4757
4758static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4759 struct sk_buff *skb,
4760 const struct net_device *in,
4761 const struct net_device *out,
4762 int (*okfn)(struct sk_buff *))
4763{
4764 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4765}
4766
4767#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4768static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4769 struct sk_buff *skb,
4770 const struct net_device *in,
4771 const struct net_device *out,
4772 int (*okfn)(struct sk_buff *))
4773{
4774 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4775}
4776#endif /* IPV6 */
4777
4778static unsigned int selinux_ip_output(struct sk_buff *skb,
4779 u16 family)
4780{
4781 struct sock *sk;
4782 u32 sid;
4783
4784 if (!netlbl_enabled())
4785 return NF_ACCEPT;
4786
4787 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4788 * because we want to make sure we apply the necessary labeling
4789 * before IPsec is applied so we can leverage AH protection */
4790 sk = skb->sk;
4791 if (sk) {
4792 struct sk_security_struct *sksec;
4793
4794 if (sk->sk_state == TCP_LISTEN)
4795 /* if the socket is the listening state then this
4796 * packet is a SYN-ACK packet which means it needs to
4797 * be labeled based on the connection/request_sock and
4798 * not the parent socket. unfortunately, we can't
4799 * lookup the request_sock yet as it isn't queued on
4800 * the parent socket until after the SYN-ACK is sent.
4801 * the "solution" is to simply pass the packet as-is
4802 * as any IP option based labeling should be copied
4803 * from the initial connection request (in the IP
4804 * layer). it is far from ideal, but until we get a
4805 * security label in the packet itself this is the
4806 * best we can do. */
4807 return NF_ACCEPT;
4808
4809 /* standard practice, label using the parent socket */
4810 sksec = sk->sk_security;
4811 sid = sksec->sid;
4812 } else
4813 sid = SECINITSID_KERNEL;
4814 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4815 return NF_DROP;
4816
4817 return NF_ACCEPT;
4818}
4819
4820static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4821 struct sk_buff *skb,
4822 const struct net_device *in,
4823 const struct net_device *out,
4824 int (*okfn)(struct sk_buff *))
4825{
4826 return selinux_ip_output(skb, PF_INET);
4827}
4828
4829static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4830 int ifindex,
4831 u16 family)
4832{
4833 struct sock *sk = skb->sk;
4834 struct sk_security_struct *sksec;
4835 struct common_audit_data ad;
4836 struct lsm_network_audit net = {0,};
4837 char *addrp;
4838 u8 proto;
4839
4840 if (sk == NULL)
4841 return NF_ACCEPT;
4842 sksec = sk->sk_security;
4843
4844 ad.type = LSM_AUDIT_DATA_NET;
4845 ad.u.net = &net;
4846 ad.u.net->netif = ifindex;
4847 ad.u.net->family = family;
4848 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4849 return NF_DROP;
4850
4851 if (selinux_secmark_enabled())
4852 if (avc_has_perm(sksec->sid, skb->secmark,
4853 SECCLASS_PACKET, PACKET__SEND, &ad))
4854 return NF_DROP_ERR(-ECONNREFUSED);
4855
4856 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4857 return NF_DROP_ERR(-ECONNREFUSED);
4858
4859 return NF_ACCEPT;
4860}
4861
4862static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4863 u16 family)
4864{
4865 u32 secmark_perm;
4866 u32 peer_sid;
4867 struct sock *sk;
4868 struct common_audit_data ad;
4869 struct lsm_network_audit net = {0,};
4870 char *addrp;
4871 u8 secmark_active;
4872 u8 peerlbl_active;
4873
4874 /* If any sort of compatibility mode is enabled then handoff processing
4875 * to the selinux_ip_postroute_compat() function to deal with the
4876 * special handling. We do this in an attempt to keep this function
4877 * as fast and as clean as possible. */
4878 if (!selinux_policycap_netpeer)
4879 return selinux_ip_postroute_compat(skb, ifindex, family);
4880
4881 secmark_active = selinux_secmark_enabled();
4882 peerlbl_active = selinux_peerlbl_enabled();
4883 if (!secmark_active && !peerlbl_active)
4884 return NF_ACCEPT;
4885
4886 sk = skb->sk;
4887
4888#ifdef CONFIG_XFRM
4889 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4890 * packet transformation so allow the packet to pass without any checks
4891 * since we'll have another chance to perform access control checks
4892 * when the packet is on it's final way out.
4893 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4894 * is NULL, in this case go ahead and apply access control.
4895 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
4896 * TCP listening state we cannot wait until the XFRM processing
4897 * is done as we will miss out on the SA label if we do;
4898 * unfortunately, this means more work, but it is only once per
4899 * connection. */
4900 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
4901 !(sk != NULL && sk->sk_state == TCP_LISTEN))
4902 return NF_ACCEPT;
4903#endif
4904
4905 if (sk == NULL) {
4906 /* Without an associated socket the packet is either coming
4907 * from the kernel or it is being forwarded; check the packet
4908 * to determine which and if the packet is being forwarded
4909 * query the packet directly to determine the security label. */
4910 if (skb->skb_iif) {
4911 secmark_perm = PACKET__FORWARD_OUT;
4912 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4913 return NF_DROP;
4914 } else {
4915 secmark_perm = PACKET__SEND;
4916 peer_sid = SECINITSID_KERNEL;
4917 }
4918 } else if (sk->sk_state == TCP_LISTEN) {
4919 /* Locally generated packet but the associated socket is in the
4920 * listening state which means this is a SYN-ACK packet. In
4921 * this particular case the correct security label is assigned
4922 * to the connection/request_sock but unfortunately we can't
4923 * query the request_sock as it isn't queued on the parent
4924 * socket until after the SYN-ACK packet is sent; the only
4925 * viable choice is to regenerate the label like we do in
4926 * selinux_inet_conn_request(). See also selinux_ip_output()
4927 * for similar problems. */
4928 u32 skb_sid;
4929 struct sk_security_struct *sksec = sk->sk_security;
4930 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
4931 return NF_DROP;
4932 /* At this point, if the returned skb peerlbl is SECSID_NULL
4933 * and the packet has been through at least one XFRM
4934 * transformation then we must be dealing with the "final"
4935 * form of labeled IPsec packet; since we've already applied
4936 * all of our access controls on this packet we can safely
4937 * pass the packet. */
4938 if (skb_sid == SECSID_NULL) {
4939 switch (family) {
4940 case PF_INET:
4941 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
4942 return NF_ACCEPT;
4943 break;
4944 case PF_INET6:
4945 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
4946 return NF_ACCEPT;
4947 default:
4948 return NF_DROP_ERR(-ECONNREFUSED);
4949 }
4950 }
4951 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
4952 return NF_DROP;
4953 secmark_perm = PACKET__SEND;
4954 } else {
4955 /* Locally generated packet, fetch the security label from the
4956 * associated socket. */
4957 struct sk_security_struct *sksec = sk->sk_security;
4958 peer_sid = sksec->sid;
4959 secmark_perm = PACKET__SEND;
4960 }
4961
4962 ad.type = LSM_AUDIT_DATA_NET;
4963 ad.u.net = &net;
4964 ad.u.net->netif = ifindex;
4965 ad.u.net->family = family;
4966 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4967 return NF_DROP;
4968
4969 if (secmark_active)
4970 if (avc_has_perm(peer_sid, skb->secmark,
4971 SECCLASS_PACKET, secmark_perm, &ad))
4972 return NF_DROP_ERR(-ECONNREFUSED);
4973
4974 if (peerlbl_active) {
4975 u32 if_sid;
4976 u32 node_sid;
4977
4978 if (sel_netif_sid(ifindex, &if_sid))
4979 return NF_DROP;
4980 if (avc_has_perm(peer_sid, if_sid,
4981 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4982 return NF_DROP_ERR(-ECONNREFUSED);
4983
4984 if (sel_netnode_sid(addrp, family, &node_sid))
4985 return NF_DROP;
4986 if (avc_has_perm(peer_sid, node_sid,
4987 SECCLASS_NODE, NODE__SENDTO, &ad))
4988 return NF_DROP_ERR(-ECONNREFUSED);
4989 }
4990
4991 return NF_ACCEPT;
4992}
4993
4994static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4995 struct sk_buff *skb,
4996 const struct net_device *in,
4997 const struct net_device *out,
4998 int (*okfn)(struct sk_buff *))
4999{
5000 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
5001}
5002
5003#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5004static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5005 struct sk_buff *skb,
5006 const struct net_device *in,
5007 const struct net_device *out,
5008 int (*okfn)(struct sk_buff *))
5009{
5010 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
5011}
5012#endif /* IPV6 */
5013
5014#endif /* CONFIG_NETFILTER */
5015
5016static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5017{
5018 int err;
5019
5020 err = cap_netlink_send(sk, skb);
5021 if (err)
5022 return err;
5023
5024 return selinux_nlmsg_perm(sk, skb);
5025}
5026
5027static int ipc_alloc_security(struct task_struct *task,
5028 struct kern_ipc_perm *perm,
5029 u16 sclass)
5030{
5031 struct ipc_security_struct *isec;
5032 u32 sid;
5033
5034 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5035 if (!isec)
5036 return -ENOMEM;
5037
5038 sid = task_sid(task);
5039 isec->sclass = sclass;
5040 isec->sid = sid;
5041 perm->security = isec;
5042
5043 return 0;
5044}
5045
5046static void ipc_free_security(struct kern_ipc_perm *perm)
5047{
5048 struct ipc_security_struct *isec = perm->security;
5049 perm->security = NULL;
5050 kfree(isec);
5051}
5052
5053static int msg_msg_alloc_security(struct msg_msg *msg)
5054{
5055 struct msg_security_struct *msec;
5056
5057 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5058 if (!msec)
5059 return -ENOMEM;
5060
5061 msec->sid = SECINITSID_UNLABELED;
5062 msg->security = msec;
5063
5064 return 0;
5065}
5066
5067static void msg_msg_free_security(struct msg_msg *msg)
5068{
5069 struct msg_security_struct *msec = msg->security;
5070
5071 msg->security = NULL;
5072 kfree(msec);
5073}
5074
5075static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5076 u32 perms)
5077{
5078 struct ipc_security_struct *isec;
5079 struct common_audit_data ad;
5080 u32 sid = current_sid();
5081
5082 isec = ipc_perms->security;
5083
5084 ad.type = LSM_AUDIT_DATA_IPC;
5085 ad.u.ipc_id = ipc_perms->key;
5086
5087 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5088}
5089
5090static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5091{
5092 return msg_msg_alloc_security(msg);
5093}
5094
5095static void selinux_msg_msg_free_security(struct msg_msg *msg)
5096{
5097 msg_msg_free_security(msg);
5098}
5099
5100/* message queue security operations */
5101static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5102{
5103 struct ipc_security_struct *isec;
5104 struct common_audit_data ad;
5105 u32 sid = current_sid();
5106 int rc;
5107
5108 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5109 if (rc)
5110 return rc;
5111
5112 isec = msq->q_perm.security;
5113
5114 ad.type = LSM_AUDIT_DATA_IPC;
5115 ad.u.ipc_id = msq->q_perm.key;
5116
5117 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5118 MSGQ__CREATE, &ad);
5119 if (rc) {
5120 ipc_free_security(&msq->q_perm);
5121 return rc;
5122 }
5123 return 0;
5124}
5125
5126static void selinux_msg_queue_free_security(struct msg_queue *msq)
5127{
5128 ipc_free_security(&msq->q_perm);
5129}
5130
5131static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5132{
5133 struct ipc_security_struct *isec;
5134 struct common_audit_data ad;
5135 u32 sid = current_sid();
5136
5137 isec = msq->q_perm.security;
5138
5139 ad.type = LSM_AUDIT_DATA_IPC;
5140 ad.u.ipc_id = msq->q_perm.key;
5141
5142 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5143 MSGQ__ASSOCIATE, &ad);
5144}
5145
5146static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5147{
5148 int err;
5149 int perms;
5150
5151 switch (cmd) {
5152 case IPC_INFO:
5153 case MSG_INFO:
5154 /* No specific object, just general system-wide information. */
5155 return task_has_system(current, SYSTEM__IPC_INFO);
5156 case IPC_STAT:
5157 case MSG_STAT:
5158 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5159 break;
5160 case IPC_SET:
5161 perms = MSGQ__SETATTR;
5162 break;
5163 case IPC_RMID:
5164 perms = MSGQ__DESTROY;
5165 break;
5166 default:
5167 return 0;
5168 }
5169
5170 err = ipc_has_perm(&msq->q_perm, perms);
5171 return err;
5172}
5173
5174static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5175{
5176 struct ipc_security_struct *isec;
5177 struct msg_security_struct *msec;
5178 struct common_audit_data ad;
5179 u32 sid = current_sid();
5180 int rc;
5181
5182 isec = msq->q_perm.security;
5183 msec = msg->security;
5184
5185 /*
5186 * First time through, need to assign label to the message
5187 */
5188 if (msec->sid == SECINITSID_UNLABELED) {
5189 /*
5190 * Compute new sid based on current process and
5191 * message queue this message will be stored in
5192 */
5193 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5194 NULL, &msec->sid);
5195 if (rc)
5196 return rc;
5197 }
5198
5199 ad.type = LSM_AUDIT_DATA_IPC;
5200 ad.u.ipc_id = msq->q_perm.key;
5201
5202 /* Can this process write to the queue? */
5203 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5204 MSGQ__WRITE, &ad);
5205 if (!rc)
5206 /* Can this process send the message */
5207 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5208 MSG__SEND, &ad);
5209 if (!rc)
5210 /* Can the message be put in the queue? */
5211 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5212 MSGQ__ENQUEUE, &ad);
5213
5214 return rc;
5215}
5216
5217static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5218 struct task_struct *target,
5219 long type, int mode)
5220{
5221 struct ipc_security_struct *isec;
5222 struct msg_security_struct *msec;
5223 struct common_audit_data ad;
5224 u32 sid = task_sid(target);
5225 int rc;
5226
5227 isec = msq->q_perm.security;
5228 msec = msg->security;
5229
5230 ad.type = LSM_AUDIT_DATA_IPC;
5231 ad.u.ipc_id = msq->q_perm.key;
5232
5233 rc = avc_has_perm(sid, isec->sid,
5234 SECCLASS_MSGQ, MSGQ__READ, &ad);
5235 if (!rc)
5236 rc = avc_has_perm(sid, msec->sid,
5237 SECCLASS_MSG, MSG__RECEIVE, &ad);
5238 return rc;
5239}
5240
5241/* Shared Memory security operations */
5242static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5243{
5244 struct ipc_security_struct *isec;
5245 struct common_audit_data ad;
5246 u32 sid = current_sid();
5247 int rc;
5248
5249 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5250 if (rc)
5251 return rc;
5252
5253 isec = shp->shm_perm.security;
5254
5255 ad.type = LSM_AUDIT_DATA_IPC;
5256 ad.u.ipc_id = shp->shm_perm.key;
5257
5258 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5259 SHM__CREATE, &ad);
5260 if (rc) {
5261 ipc_free_security(&shp->shm_perm);
5262 return rc;
5263 }
5264 return 0;
5265}
5266
5267static void selinux_shm_free_security(struct shmid_kernel *shp)
5268{
5269 ipc_free_security(&shp->shm_perm);
5270}
5271
5272static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5273{
5274 struct ipc_security_struct *isec;
5275 struct common_audit_data ad;
5276 u32 sid = current_sid();
5277
5278 isec = shp->shm_perm.security;
5279
5280 ad.type = LSM_AUDIT_DATA_IPC;
5281 ad.u.ipc_id = shp->shm_perm.key;
5282
5283 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5284 SHM__ASSOCIATE, &ad);
5285}
5286
5287/* Note, at this point, shp is locked down */
5288static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5289{
5290 int perms;
5291 int err;
5292
5293 switch (cmd) {
5294 case IPC_INFO:
5295 case SHM_INFO:
5296 /* No specific object, just general system-wide information. */
5297 return task_has_system(current, SYSTEM__IPC_INFO);
5298 case IPC_STAT:
5299 case SHM_STAT:
5300 perms = SHM__GETATTR | SHM__ASSOCIATE;
5301 break;
5302 case IPC_SET:
5303 perms = SHM__SETATTR;
5304 break;
5305 case SHM_LOCK:
5306 case SHM_UNLOCK:
5307 perms = SHM__LOCK;
5308 break;
5309 case IPC_RMID:
5310 perms = SHM__DESTROY;
5311 break;
5312 default:
5313 return 0;
5314 }
5315
5316 err = ipc_has_perm(&shp->shm_perm, perms);
5317 return err;
5318}
5319
5320static int selinux_shm_shmat(struct shmid_kernel *shp,
5321 char __user *shmaddr, int shmflg)
5322{
5323 u32 perms;
5324
5325 if (shmflg & SHM_RDONLY)
5326 perms = SHM__READ;
5327 else
5328 perms = SHM__READ | SHM__WRITE;
5329
5330 return ipc_has_perm(&shp->shm_perm, perms);
5331}
5332
5333/* Semaphore security operations */
5334static int selinux_sem_alloc_security(struct sem_array *sma)
5335{
5336 struct ipc_security_struct *isec;
5337 struct common_audit_data ad;
5338 u32 sid = current_sid();
5339 int rc;
5340
5341 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5342 if (rc)
5343 return rc;
5344
5345 isec = sma->sem_perm.security;
5346
5347 ad.type = LSM_AUDIT_DATA_IPC;
5348 ad.u.ipc_id = sma->sem_perm.key;
5349
5350 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5351 SEM__CREATE, &ad);
5352 if (rc) {
5353 ipc_free_security(&sma->sem_perm);
5354 return rc;
5355 }
5356 return 0;
5357}
5358
5359static void selinux_sem_free_security(struct sem_array *sma)
5360{
5361 ipc_free_security(&sma->sem_perm);
5362}
5363
5364static int selinux_sem_associate(struct sem_array *sma, int semflg)
5365{
5366 struct ipc_security_struct *isec;
5367 struct common_audit_data ad;
5368 u32 sid = current_sid();
5369
5370 isec = sma->sem_perm.security;
5371
5372 ad.type = LSM_AUDIT_DATA_IPC;
5373 ad.u.ipc_id = sma->sem_perm.key;
5374
5375 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5376 SEM__ASSOCIATE, &ad);
5377}
5378
5379/* Note, at this point, sma is locked down */
5380static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5381{
5382 int err;
5383 u32 perms;
5384
5385 switch (cmd) {
5386 case IPC_INFO:
5387 case SEM_INFO:
5388 /* No specific object, just general system-wide information. */
5389 return task_has_system(current, SYSTEM__IPC_INFO);
5390 case GETPID:
5391 case GETNCNT:
5392 case GETZCNT:
5393 perms = SEM__GETATTR;
5394 break;
5395 case GETVAL:
5396 case GETALL:
5397 perms = SEM__READ;
5398 break;
5399 case SETVAL:
5400 case SETALL:
5401 perms = SEM__WRITE;
5402 break;
5403 case IPC_RMID:
5404 perms = SEM__DESTROY;
5405 break;
5406 case IPC_SET:
5407 perms = SEM__SETATTR;
5408 break;
5409 case IPC_STAT:
5410 case SEM_STAT:
5411 perms = SEM__GETATTR | SEM__ASSOCIATE;
5412 break;
5413 default:
5414 return 0;
5415 }
5416
5417 err = ipc_has_perm(&sma->sem_perm, perms);
5418 return err;
5419}
5420
5421static int selinux_sem_semop(struct sem_array *sma,
5422 struct sembuf *sops, unsigned nsops, int alter)
5423{
5424 u32 perms;
5425
5426 if (alter)
5427 perms = SEM__READ | SEM__WRITE;
5428 else
5429 perms = SEM__READ;
5430
5431 return ipc_has_perm(&sma->sem_perm, perms);
5432}
5433
5434static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5435{
5436 u32 av = 0;
5437
5438 av = 0;
5439 if (flag & S_IRUGO)
5440 av |= IPC__UNIX_READ;
5441 if (flag & S_IWUGO)
5442 av |= IPC__UNIX_WRITE;
5443
5444 if (av == 0)
5445 return 0;
5446
5447 return ipc_has_perm(ipcp, av);
5448}
5449
5450static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5451{
5452 struct ipc_security_struct *isec = ipcp->security;
5453 *secid = isec->sid;
5454}
5455
5456static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5457{
5458 if (inode)
5459 inode_doinit_with_dentry(inode, dentry);
5460}
5461
5462static int selinux_getprocattr(struct task_struct *p,
5463 char *name, char **value)
5464{
5465 const struct task_security_struct *__tsec;
5466 u32 sid;
5467 int error;
5468 unsigned len;
5469
5470 if (current != p) {
5471 error = current_has_perm(p, PROCESS__GETATTR);
5472 if (error)
5473 return error;
5474 }
5475
5476 rcu_read_lock();
5477 __tsec = __task_cred(p)->security;
5478
5479 if (!strcmp(name, "current"))
5480 sid = __tsec->sid;
5481 else if (!strcmp(name, "prev"))
5482 sid = __tsec->osid;
5483 else if (!strcmp(name, "exec"))
5484 sid = __tsec->exec_sid;
5485 else if (!strcmp(name, "fscreate"))
5486 sid = __tsec->create_sid;
5487 else if (!strcmp(name, "keycreate"))
5488 sid = __tsec->keycreate_sid;
5489 else if (!strcmp(name, "sockcreate"))
5490 sid = __tsec->sockcreate_sid;
5491 else
5492 goto invalid;
5493 rcu_read_unlock();
5494
5495 if (!sid)
5496 return 0;
5497
5498 error = security_sid_to_context(sid, value, &len);
5499 if (error)
5500 return error;
5501 return len;
5502
5503invalid:
5504 rcu_read_unlock();
5505 return -EINVAL;
5506}
5507
5508static int selinux_setprocattr(struct task_struct *p,
5509 char *name, void *value, size_t size)
5510{
5511 struct task_security_struct *tsec;
5512 struct task_struct *tracer;
5513 struct cred *new;
5514 u32 sid = 0, ptsid;
5515 int error;
5516 char *str = value;
5517
5518 if (current != p) {
5519 /* SELinux only allows a process to change its own
5520 security attributes. */
5521 return -EACCES;
5522 }
5523
5524 /*
5525 * Basic control over ability to set these attributes at all.
5526 * current == p, but we'll pass them separately in case the
5527 * above restriction is ever removed.
5528 */
5529 if (!strcmp(name, "exec"))
5530 error = current_has_perm(p, PROCESS__SETEXEC);
5531 else if (!strcmp(name, "fscreate"))
5532 error = current_has_perm(p, PROCESS__SETFSCREATE);
5533 else if (!strcmp(name, "keycreate"))
5534 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5535 else if (!strcmp(name, "sockcreate"))
5536 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5537 else if (!strcmp(name, "current"))
5538 error = current_has_perm(p, PROCESS__SETCURRENT);
5539 else
5540 error = -EINVAL;
5541 if (error)
5542 return error;
5543
5544 /* Obtain a SID for the context, if one was specified. */
5545 if (size && str[1] && str[1] != '\n') {
5546 if (str[size-1] == '\n') {
5547 str[size-1] = 0;
5548 size--;
5549 }
5550 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5551 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5552 if (!capable(CAP_MAC_ADMIN)) {
5553 struct audit_buffer *ab;
5554 size_t audit_size;
5555
5556 /* We strip a nul only if it is at the end, otherwise the
5557 * context contains a nul and we should audit that */
5558 if (str[size - 1] == '\0')
5559 audit_size = size - 1;
5560 else
5561 audit_size = size;
5562 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5563 audit_log_format(ab, "op=fscreate invalid_context=");
5564 audit_log_n_untrustedstring(ab, value, audit_size);
5565 audit_log_end(ab);
5566
5567 return error;
5568 }
5569 error = security_context_to_sid_force(value, size,
5570 &sid);
5571 }
5572 if (error)
5573 return error;
5574 }
5575
5576 new = prepare_creds();
5577 if (!new)
5578 return -ENOMEM;
5579
5580 /* Permission checking based on the specified context is
5581 performed during the actual operation (execve,
5582 open/mkdir/...), when we know the full context of the
5583 operation. See selinux_bprm_set_creds for the execve
5584 checks and may_create for the file creation checks. The
5585 operation will then fail if the context is not permitted. */
5586 tsec = new->security;
5587 if (!strcmp(name, "exec")) {
5588 tsec->exec_sid = sid;
5589 } else if (!strcmp(name, "fscreate")) {
5590 tsec->create_sid = sid;
5591 } else if (!strcmp(name, "keycreate")) {
5592 error = may_create_key(sid, p);
5593 if (error)
5594 goto abort_change;
5595 tsec->keycreate_sid = sid;
5596 } else if (!strcmp(name, "sockcreate")) {
5597 tsec->sockcreate_sid = sid;
5598 } else if (!strcmp(name, "current")) {
5599 error = -EINVAL;
5600 if (sid == 0)
5601 goto abort_change;
5602
5603 /* Only allow single threaded processes to change context */
5604 error = -EPERM;
5605 if (!current_is_single_threaded()) {
5606 error = security_bounded_transition(tsec->sid, sid);
5607 if (error)
5608 goto abort_change;
5609 }
5610
5611 /* Check permissions for the transition. */
5612 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5613 PROCESS__DYNTRANSITION, NULL);
5614 if (error)
5615 goto abort_change;
5616
5617 /* Check for ptracing, and update the task SID if ok.
5618 Otherwise, leave SID unchanged and fail. */
5619 ptsid = 0;
5620 rcu_read_lock();
5621 tracer = ptrace_parent(p);
5622 if (tracer)
5623 ptsid = task_sid(tracer);
5624 rcu_read_unlock();
5625
5626 if (tracer) {
5627 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5628 PROCESS__PTRACE, NULL);
5629 if (error)
5630 goto abort_change;
5631 }
5632
5633 tsec->sid = sid;
5634 } else {
5635 error = -EINVAL;
5636 goto abort_change;
5637 }
5638
5639 commit_creds(new);
5640 return size;
5641
5642abort_change:
5643 abort_creds(new);
5644 return error;
5645}
5646
5647static int selinux_ismaclabel(const char *name)
5648{
5649 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5650}
5651
5652static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5653{
5654 return security_sid_to_context(secid, secdata, seclen);
5655}
5656
5657static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5658{
5659 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5660}
5661
5662static void selinux_release_secctx(char *secdata, u32 seclen)
5663{
5664 kfree(secdata);
5665}
5666
5667/*
5668 * called with inode->i_mutex locked
5669 */
5670static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5671{
5672 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5673}
5674
5675/*
5676 * called with inode->i_mutex locked
5677 */
5678static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5679{
5680 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5681}
5682
5683static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5684{
5685 int len = 0;
5686 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5687 ctx, true);
5688 if (len < 0)
5689 return len;
5690 *ctxlen = len;
5691 return 0;
5692}
5693#ifdef CONFIG_KEYS
5694
5695static int selinux_key_alloc(struct key *k, const struct cred *cred,
5696 unsigned long flags)
5697{
5698 const struct task_security_struct *tsec;
5699 struct key_security_struct *ksec;
5700
5701 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5702 if (!ksec)
5703 return -ENOMEM;
5704
5705 tsec = cred->security;
5706 if (tsec->keycreate_sid)
5707 ksec->sid = tsec->keycreate_sid;
5708 else
5709 ksec->sid = tsec->sid;
5710
5711 k->security = ksec;
5712 return 0;
5713}
5714
5715static void selinux_key_free(struct key *k)
5716{
5717 struct key_security_struct *ksec = k->security;
5718
5719 k->security = NULL;
5720 kfree(ksec);
5721}
5722
5723static int selinux_key_permission(key_ref_t key_ref,
5724 const struct cred *cred,
5725 key_perm_t perm)
5726{
5727 struct key *key;
5728 struct key_security_struct *ksec;
5729 u32 sid;
5730
5731 /* if no specific permissions are requested, we skip the
5732 permission check. No serious, additional covert channels
5733 appear to be created. */
5734 if (perm == 0)
5735 return 0;
5736
5737 sid = cred_sid(cred);
5738
5739 key = key_ref_to_ptr(key_ref);
5740 ksec = key->security;
5741
5742 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5743}
5744
5745static int selinux_key_getsecurity(struct key *key, char **_buffer)
5746{
5747 struct key_security_struct *ksec = key->security;
5748 char *context = NULL;
5749 unsigned len;
5750 int rc;
5751
5752 rc = security_sid_to_context(ksec->sid, &context, &len);
5753 if (!rc)
5754 rc = len;
5755 *_buffer = context;
5756 return rc;
5757}
5758
5759#endif
5760
5761static struct security_operations selinux_ops = {
5762 .name = "selinux",
5763
5764 .ptrace_access_check = selinux_ptrace_access_check,
5765 .ptrace_traceme = selinux_ptrace_traceme,
5766 .capget = selinux_capget,
5767 .capset = selinux_capset,
5768 .capable = selinux_capable,
5769 .quotactl = selinux_quotactl,
5770 .quota_on = selinux_quota_on,
5771 .syslog = selinux_syslog,
5772 .vm_enough_memory = selinux_vm_enough_memory,
5773
5774 .netlink_send = selinux_netlink_send,
5775
5776 .bprm_set_creds = selinux_bprm_set_creds,
5777 .bprm_committing_creds = selinux_bprm_committing_creds,
5778 .bprm_committed_creds = selinux_bprm_committed_creds,
5779 .bprm_secureexec = selinux_bprm_secureexec,
5780
5781 .sb_alloc_security = selinux_sb_alloc_security,
5782 .sb_free_security = selinux_sb_free_security,
5783 .sb_copy_data = selinux_sb_copy_data,
5784 .sb_remount = selinux_sb_remount,
5785 .sb_kern_mount = selinux_sb_kern_mount,
5786 .sb_show_options = selinux_sb_show_options,
5787 .sb_statfs = selinux_sb_statfs,
5788 .sb_mount = selinux_mount,
5789 .sb_umount = selinux_umount,
5790 .sb_set_mnt_opts = selinux_set_mnt_opts,
5791 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5792 .sb_parse_opts_str = selinux_parse_opts_str,
5793
5794 .dentry_init_security = selinux_dentry_init_security,
5795
5796 .inode_alloc_security = selinux_inode_alloc_security,
5797 .inode_free_security = selinux_inode_free_security,
5798 .inode_init_security = selinux_inode_init_security,
5799 .inode_create = selinux_inode_create,
5800 .inode_link = selinux_inode_link,
5801 .inode_unlink = selinux_inode_unlink,
5802 .inode_symlink = selinux_inode_symlink,
5803 .inode_mkdir = selinux_inode_mkdir,
5804 .inode_rmdir = selinux_inode_rmdir,
5805 .inode_mknod = selinux_inode_mknod,
5806 .inode_rename = selinux_inode_rename,
5807 .inode_readlink = selinux_inode_readlink,
5808 .inode_follow_link = selinux_inode_follow_link,
5809 .inode_permission = selinux_inode_permission,
5810 .inode_setattr = selinux_inode_setattr,
5811 .inode_getattr = selinux_inode_getattr,
5812 .inode_setxattr = selinux_inode_setxattr,
5813 .inode_post_setxattr = selinux_inode_post_setxattr,
5814 .inode_getxattr = selinux_inode_getxattr,
5815 .inode_listxattr = selinux_inode_listxattr,
5816 .inode_removexattr = selinux_inode_removexattr,
5817 .inode_getsecurity = selinux_inode_getsecurity,
5818 .inode_setsecurity = selinux_inode_setsecurity,
5819 .inode_listsecurity = selinux_inode_listsecurity,
5820 .inode_getsecid = selinux_inode_getsecid,
5821
5822 .file_permission = selinux_file_permission,
5823 .file_alloc_security = selinux_file_alloc_security,
5824 .file_free_security = selinux_file_free_security,
5825 .file_ioctl = selinux_file_ioctl,
5826 .mmap_file = selinux_mmap_file,
5827 .mmap_addr = selinux_mmap_addr,
5828 .file_mprotect = selinux_file_mprotect,
5829 .file_lock = selinux_file_lock,
5830 .file_fcntl = selinux_file_fcntl,
5831 .file_set_fowner = selinux_file_set_fowner,
5832 .file_send_sigiotask = selinux_file_send_sigiotask,
5833 .file_receive = selinux_file_receive,
5834
5835 .file_open = selinux_file_open,
5836
5837 .task_create = selinux_task_create,
5838 .cred_alloc_blank = selinux_cred_alloc_blank,
5839 .cred_free = selinux_cred_free,
5840 .cred_prepare = selinux_cred_prepare,
5841 .cred_transfer = selinux_cred_transfer,
5842 .kernel_act_as = selinux_kernel_act_as,
5843 .kernel_create_files_as = selinux_kernel_create_files_as,
5844 .kernel_module_request = selinux_kernel_module_request,
5845 .task_setpgid = selinux_task_setpgid,
5846 .task_getpgid = selinux_task_getpgid,
5847 .task_getsid = selinux_task_getsid,
5848 .task_getsecid = selinux_task_getsecid,
5849 .task_setnice = selinux_task_setnice,
5850 .task_setioprio = selinux_task_setioprio,
5851 .task_getioprio = selinux_task_getioprio,
5852 .task_setrlimit = selinux_task_setrlimit,
5853 .task_setscheduler = selinux_task_setscheduler,
5854 .task_getscheduler = selinux_task_getscheduler,
5855 .task_movememory = selinux_task_movememory,
5856 .task_kill = selinux_task_kill,
5857 .task_wait = selinux_task_wait,
5858 .task_to_inode = selinux_task_to_inode,
5859
5860 .ipc_permission = selinux_ipc_permission,
5861 .ipc_getsecid = selinux_ipc_getsecid,
5862
5863 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5864 .msg_msg_free_security = selinux_msg_msg_free_security,
5865
5866 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5867 .msg_queue_free_security = selinux_msg_queue_free_security,
5868 .msg_queue_associate = selinux_msg_queue_associate,
5869 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5870 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5871 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5872
5873 .shm_alloc_security = selinux_shm_alloc_security,
5874 .shm_free_security = selinux_shm_free_security,
5875 .shm_associate = selinux_shm_associate,
5876 .shm_shmctl = selinux_shm_shmctl,
5877 .shm_shmat = selinux_shm_shmat,
5878
5879 .sem_alloc_security = selinux_sem_alloc_security,
5880 .sem_free_security = selinux_sem_free_security,
5881 .sem_associate = selinux_sem_associate,
5882 .sem_semctl = selinux_sem_semctl,
5883 .sem_semop = selinux_sem_semop,
5884
5885 .d_instantiate = selinux_d_instantiate,
5886
5887 .getprocattr = selinux_getprocattr,
5888 .setprocattr = selinux_setprocattr,
5889
5890 .ismaclabel = selinux_ismaclabel,
5891 .secid_to_secctx = selinux_secid_to_secctx,
5892 .secctx_to_secid = selinux_secctx_to_secid,
5893 .release_secctx = selinux_release_secctx,
5894 .inode_notifysecctx = selinux_inode_notifysecctx,
5895 .inode_setsecctx = selinux_inode_setsecctx,
5896 .inode_getsecctx = selinux_inode_getsecctx,
5897
5898 .unix_stream_connect = selinux_socket_unix_stream_connect,
5899 .unix_may_send = selinux_socket_unix_may_send,
5900
5901 .socket_create = selinux_socket_create,
5902 .socket_post_create = selinux_socket_post_create,
5903 .socket_bind = selinux_socket_bind,
5904 .socket_connect = selinux_socket_connect,
5905 .socket_listen = selinux_socket_listen,
5906 .socket_accept = selinux_socket_accept,
5907 .socket_sendmsg = selinux_socket_sendmsg,
5908 .socket_recvmsg = selinux_socket_recvmsg,
5909 .socket_getsockname = selinux_socket_getsockname,
5910 .socket_getpeername = selinux_socket_getpeername,
5911 .socket_getsockopt = selinux_socket_getsockopt,
5912 .socket_setsockopt = selinux_socket_setsockopt,
5913 .socket_shutdown = selinux_socket_shutdown,
5914 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5915 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5916 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5917 .sk_alloc_security = selinux_sk_alloc_security,
5918 .sk_free_security = selinux_sk_free_security,
5919 .sk_clone_security = selinux_sk_clone_security,
5920 .sk_getsecid = selinux_sk_getsecid,
5921 .sock_graft = selinux_sock_graft,
5922 .inet_conn_request = selinux_inet_conn_request,
5923 .inet_csk_clone = selinux_inet_csk_clone,
5924 .inet_conn_established = selinux_inet_conn_established,
5925 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5926 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5927 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5928 .req_classify_flow = selinux_req_classify_flow,
5929 .tun_dev_alloc_security = selinux_tun_dev_alloc_security,
5930 .tun_dev_free_security = selinux_tun_dev_free_security,
5931 .tun_dev_create = selinux_tun_dev_create,
5932 .tun_dev_attach_queue = selinux_tun_dev_attach_queue,
5933 .tun_dev_attach = selinux_tun_dev_attach,
5934 .tun_dev_open = selinux_tun_dev_open,
5935 .skb_owned_by = selinux_skb_owned_by,
5936
5937#ifdef CONFIG_SECURITY_NETWORK_XFRM
5938 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5939 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5940 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5941 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5942 .xfrm_state_alloc = selinux_xfrm_state_alloc,
5943 .xfrm_state_alloc_acquire = selinux_xfrm_state_alloc_acquire,
5944 .xfrm_state_free_security = selinux_xfrm_state_free,
5945 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5946 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5947 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5948 .xfrm_decode_session = selinux_xfrm_decode_session,
5949#endif
5950
5951#ifdef CONFIG_KEYS
5952 .key_alloc = selinux_key_alloc,
5953 .key_free = selinux_key_free,
5954 .key_permission = selinux_key_permission,
5955 .key_getsecurity = selinux_key_getsecurity,
5956#endif
5957
5958#ifdef CONFIG_AUDIT
5959 .audit_rule_init = selinux_audit_rule_init,
5960 .audit_rule_known = selinux_audit_rule_known,
5961 .audit_rule_match = selinux_audit_rule_match,
5962 .audit_rule_free = selinux_audit_rule_free,
5963#endif
5964};
5965
5966static __init int selinux_init(void)
5967{
5968 if (!security_module_enable(&selinux_ops)) {
5969 selinux_enabled = 0;
5970 return 0;
5971 }
5972
5973 if (!selinux_enabled) {
5974 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5975 return 0;
5976 }
5977
5978 printk(KERN_INFO "SELinux: Initializing.\n");
5979
5980 /* Set the security state for the initial task. */
5981 cred_init_security();
5982
5983 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5984
5985 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5986 sizeof(struct inode_security_struct),
5987 0, SLAB_PANIC, NULL);
5988 avc_init();
5989
5990 if (register_security(&selinux_ops))
5991 panic("SELinux: Unable to register with kernel.\n");
5992
5993 if (selinux_enforcing)
5994 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5995 else
5996 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5997
5998 return 0;
5999}
6000
6001static void delayed_superblock_init(struct super_block *sb, void *unused)
6002{
6003 superblock_doinit(sb, NULL);
6004}
6005
6006void selinux_complete_init(void)
6007{
6008 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6009
6010 /* Set up any superblocks initialized prior to the policy load. */
6011 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6012 iterate_supers(delayed_superblock_init, NULL);
6013}
6014
6015/* SELinux requires early initialization in order to label
6016 all processes and objects when they are created. */
6017security_initcall(selinux_init);
6018
6019#if defined(CONFIG_NETFILTER)
6020
6021static struct nf_hook_ops selinux_ipv4_ops[] = {
6022 {
6023 .hook = selinux_ipv4_postroute,
6024 .owner = THIS_MODULE,
6025 .pf = NFPROTO_IPV4,
6026 .hooknum = NF_INET_POST_ROUTING,
6027 .priority = NF_IP_PRI_SELINUX_LAST,
6028 },
6029 {
6030 .hook = selinux_ipv4_forward,
6031 .owner = THIS_MODULE,
6032 .pf = NFPROTO_IPV4,
6033 .hooknum = NF_INET_FORWARD,
6034 .priority = NF_IP_PRI_SELINUX_FIRST,
6035 },
6036 {
6037 .hook = selinux_ipv4_output,
6038 .owner = THIS_MODULE,
6039 .pf = NFPROTO_IPV4,
6040 .hooknum = NF_INET_LOCAL_OUT,
6041 .priority = NF_IP_PRI_SELINUX_FIRST,
6042 }
6043};
6044
6045#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6046
6047static struct nf_hook_ops selinux_ipv6_ops[] = {
6048 {
6049 .hook = selinux_ipv6_postroute,
6050 .owner = THIS_MODULE,
6051 .pf = NFPROTO_IPV6,
6052 .hooknum = NF_INET_POST_ROUTING,
6053 .priority = NF_IP6_PRI_SELINUX_LAST,
6054 },
6055 {
6056 .hook = selinux_ipv6_forward,
6057 .owner = THIS_MODULE,
6058 .pf = NFPROTO_IPV6,
6059 .hooknum = NF_INET_FORWARD,
6060 .priority = NF_IP6_PRI_SELINUX_FIRST,
6061 }
6062};
6063
6064#endif /* IPV6 */
6065
6066static int __init selinux_nf_ip_init(void)
6067{
6068 int err = 0;
6069
6070 if (!selinux_enabled)
6071 goto out;
6072
6073 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6074
6075 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6076 if (err)
6077 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
6078
6079#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6080 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6081 if (err)
6082 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
6083#endif /* IPV6 */
6084
6085out:
6086 return err;
6087}
6088
6089__initcall(selinux_nf_ip_init);
6090
6091#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6092static void selinux_nf_ip_exit(void)
6093{
6094 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6095
6096 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6097#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6098 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6099#endif /* IPV6 */
6100}
6101#endif
6102
6103#else /* CONFIG_NETFILTER */
6104
6105#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6106#define selinux_nf_ip_exit()
6107#endif
6108
6109#endif /* CONFIG_NETFILTER */
6110
6111#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6112static int selinux_disabled;
6113
6114int selinux_disable(void)
6115{
6116 if (ss_initialized) {
6117 /* Not permitted after initial policy load. */
6118 return -EINVAL;
6119 }
6120
6121 if (selinux_disabled) {
6122 /* Only do this once. */
6123 return -EINVAL;
6124 }
6125
6126 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6127
6128 selinux_disabled = 1;
6129 selinux_enabled = 0;
6130
6131 reset_security_ops();
6132
6133 /* Try to destroy the avc node cache */
6134 avc_disable();
6135
6136 /* Unregister netfilter hooks. */
6137 selinux_nf_ip_exit();
6138
6139 /* Unregister selinuxfs. */
6140 exit_sel_fs();
6141
6142 return 0;
6143}
6144#endif