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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/ext2_fs.h>
32#include <linux/sched.h>
33#include <linux/security.h>
34#include <linux/xattr.h>
35#include <linux/capability.h>
36#include <linux/unistd.h>
37#include <linux/mm.h>
38#include <linux/mman.h>
39#include <linux/slab.h>
40#include <linux/pagemap.h>
41#include <linux/proc_fs.h>
42#include <linux/swap.h>
43#include <linux/spinlock.h>
44#include <linux/syscalls.h>
45#include <linux/dcache.h>
46#include <linux/file.h>
47#include <linux/fdtable.h>
48#include <linux/namei.h>
49#include <linux/mount.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/net_namespace.h>
57#include <net/netlabel.h>
58#include <linux/uaccess.h>
59#include <asm/ioctls.h>
60#include <linux/atomic.h>
61#include <linux/bitops.h>
62#include <linux/interrupt.h>
63#include <linux/netdevice.h> /* for network interface checks */
64#include <linux/netlink.h>
65#include <linux/tcp.h>
66#include <linux/udp.h>
67#include <linux/dccp.h>
68#include <linux/quota.h>
69#include <linux/un.h> /* for Unix socket types */
70#include <net/af_unix.h> /* for Unix socket types */
71#include <linux/parser.h>
72#include <linux/nfs_mount.h>
73#include <net/ipv6.h>
74#include <linux/hugetlb.h>
75#include <linux/personality.h>
76#include <linux/audit.h>
77#include <linux/string.h>
78#include <linux/selinux.h>
79#include <linux/mutex.h>
80#include <linux/posix-timers.h>
81#include <linux/syslog.h>
82#include <linux/user_namespace.h>
83
84#include "avc.h"
85#include "objsec.h"
86#include "netif.h"
87#include "netnode.h"
88#include "netport.h"
89#include "xfrm.h"
90#include "netlabel.h"
91#include "audit.h"
92
93#define NUM_SEL_MNT_OPTS 5
94
95extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96extern struct security_operations *security_ops;
97
98/* SECMARK reference count */
99atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102int selinux_enforcing;
103
104static int __init enforcing_setup(char *str)
105{
106 unsigned long enforcing;
107 if (!strict_strtoul(str, 0, &enforcing))
108 selinux_enforcing = enforcing ? 1 : 0;
109 return 1;
110}
111__setup("enforcing=", enforcing_setup);
112#endif
113
114#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117static int __init selinux_enabled_setup(char *str)
118{
119 unsigned long enabled;
120 if (!strict_strtoul(str, 0, &enabled))
121 selinux_enabled = enabled ? 1 : 0;
122 return 1;
123}
124__setup("selinux=", selinux_enabled_setup);
125#else
126int selinux_enabled = 1;
127#endif
128
129static struct kmem_cache *sel_inode_cache;
130
131/**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled.
139 *
140 */
141static int selinux_secmark_enabled(void)
142{
143 return (atomic_read(&selinux_secmark_refcount) > 0);
144}
145
146/*
147 * initialise the security for the init task
148 */
149static void cred_init_security(void)
150{
151 struct cred *cred = (struct cred *) current->real_cred;
152 struct task_security_struct *tsec;
153
154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155 if (!tsec)
156 panic("SELinux: Failed to initialize initial task.\n");
157
158 tsec->osid = tsec->sid = SECINITSID_KERNEL;
159 cred->security = tsec;
160}
161
162/*
163 * get the security ID of a set of credentials
164 */
165static inline u32 cred_sid(const struct cred *cred)
166{
167 const struct task_security_struct *tsec;
168
169 tsec = cred->security;
170 return tsec->sid;
171}
172
173/*
174 * get the objective security ID of a task
175 */
176static inline u32 task_sid(const struct task_struct *task)
177{
178 u32 sid;
179
180 rcu_read_lock();
181 sid = cred_sid(__task_cred(task));
182 rcu_read_unlock();
183 return sid;
184}
185
186/*
187 * get the subjective security ID of the current task
188 */
189static inline u32 current_sid(void)
190{
191 const struct task_security_struct *tsec = current_security();
192
193 return tsec->sid;
194}
195
196/* Allocate and free functions for each kind of security blob. */
197
198static int inode_alloc_security(struct inode *inode)
199{
200 struct inode_security_struct *isec;
201 u32 sid = current_sid();
202
203 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204 if (!isec)
205 return -ENOMEM;
206
207 mutex_init(&isec->lock);
208 INIT_LIST_HEAD(&isec->list);
209 isec->inode = inode;
210 isec->sid = SECINITSID_UNLABELED;
211 isec->sclass = SECCLASS_FILE;
212 isec->task_sid = sid;
213 inode->i_security = isec;
214
215 return 0;
216}
217
218static void inode_free_security(struct inode *inode)
219{
220 struct inode_security_struct *isec = inode->i_security;
221 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223 spin_lock(&sbsec->isec_lock);
224 if (!list_empty(&isec->list))
225 list_del_init(&isec->list);
226 spin_unlock(&sbsec->isec_lock);
227
228 inode->i_security = NULL;
229 kmem_cache_free(sel_inode_cache, isec);
230}
231
232static int file_alloc_security(struct file *file)
233{
234 struct file_security_struct *fsec;
235 u32 sid = current_sid();
236
237 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238 if (!fsec)
239 return -ENOMEM;
240
241 fsec->sid = sid;
242 fsec->fown_sid = sid;
243 file->f_security = fsec;
244
245 return 0;
246}
247
248static void file_free_security(struct file *file)
249{
250 struct file_security_struct *fsec = file->f_security;
251 file->f_security = NULL;
252 kfree(fsec);
253}
254
255static int superblock_alloc_security(struct super_block *sb)
256{
257 struct superblock_security_struct *sbsec;
258
259 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260 if (!sbsec)
261 return -ENOMEM;
262
263 mutex_init(&sbsec->lock);
264 INIT_LIST_HEAD(&sbsec->isec_head);
265 spin_lock_init(&sbsec->isec_lock);
266 sbsec->sb = sb;
267 sbsec->sid = SECINITSID_UNLABELED;
268 sbsec->def_sid = SECINITSID_FILE;
269 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270 sb->s_security = sbsec;
271
272 return 0;
273}
274
275static void superblock_free_security(struct super_block *sb)
276{
277 struct superblock_security_struct *sbsec = sb->s_security;
278 sb->s_security = NULL;
279 kfree(sbsec);
280}
281
282/* The security server must be initialized before
283 any labeling or access decisions can be provided. */
284extern int ss_initialized;
285
286/* The file system's label must be initialized prior to use. */
287
288static const char *labeling_behaviors[6] = {
289 "uses xattr",
290 "uses transition SIDs",
291 "uses task SIDs",
292 "uses genfs_contexts",
293 "not configured for labeling",
294 "uses mountpoint labeling",
295};
296
297static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299static inline int inode_doinit(struct inode *inode)
300{
301 return inode_doinit_with_dentry(inode, NULL);
302}
303
304enum {
305 Opt_error = -1,
306 Opt_context = 1,
307 Opt_fscontext = 2,
308 Opt_defcontext = 3,
309 Opt_rootcontext = 4,
310 Opt_labelsupport = 5,
311};
312
313static const match_table_t tokens = {
314 {Opt_context, CONTEXT_STR "%s"},
315 {Opt_fscontext, FSCONTEXT_STR "%s"},
316 {Opt_defcontext, DEFCONTEXT_STR "%s"},
317 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318 {Opt_labelsupport, LABELSUPP_STR},
319 {Opt_error, NULL},
320};
321
322#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
323
324static int may_context_mount_sb_relabel(u32 sid,
325 struct superblock_security_struct *sbsec,
326 const struct cred *cred)
327{
328 const struct task_security_struct *tsec = cred->security;
329 int rc;
330
331 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332 FILESYSTEM__RELABELFROM, NULL);
333 if (rc)
334 return rc;
335
336 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337 FILESYSTEM__RELABELTO, NULL);
338 return rc;
339}
340
341static int may_context_mount_inode_relabel(u32 sid,
342 struct superblock_security_struct *sbsec,
343 const struct cred *cred)
344{
345 const struct task_security_struct *tsec = cred->security;
346 int rc;
347 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348 FILESYSTEM__RELABELFROM, NULL);
349 if (rc)
350 return rc;
351
352 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353 FILESYSTEM__ASSOCIATE, NULL);
354 return rc;
355}
356
357static int sb_finish_set_opts(struct super_block *sb)
358{
359 struct superblock_security_struct *sbsec = sb->s_security;
360 struct dentry *root = sb->s_root;
361 struct inode *root_inode = root->d_inode;
362 int rc = 0;
363
364 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365 /* Make sure that the xattr handler exists and that no
366 error other than -ENODATA is returned by getxattr on
367 the root directory. -ENODATA is ok, as this may be
368 the first boot of the SELinux kernel before we have
369 assigned xattr values to the filesystem. */
370 if (!root_inode->i_op->getxattr) {
371 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372 "xattr support\n", sb->s_id, sb->s_type->name);
373 rc = -EOPNOTSUPP;
374 goto out;
375 }
376 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377 if (rc < 0 && rc != -ENODATA) {
378 if (rc == -EOPNOTSUPP)
379 printk(KERN_WARNING "SELinux: (dev %s, type "
380 "%s) has no security xattr handler\n",
381 sb->s_id, sb->s_type->name);
382 else
383 printk(KERN_WARNING "SELinux: (dev %s, type "
384 "%s) getxattr errno %d\n", sb->s_id,
385 sb->s_type->name, -rc);
386 goto out;
387 }
388 }
389
390 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394 sb->s_id, sb->s_type->name);
395 else
396 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397 sb->s_id, sb->s_type->name,
398 labeling_behaviors[sbsec->behavior-1]);
399
400 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402 sbsec->behavior == SECURITY_FS_USE_NONE ||
403 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404 sbsec->flags &= ~SE_SBLABELSUPP;
405
406 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408 sbsec->flags |= SE_SBLABELSUPP;
409
410 /* Initialize the root inode. */
411 rc = inode_doinit_with_dentry(root_inode, root);
412
413 /* Initialize any other inodes associated with the superblock, e.g.
414 inodes created prior to initial policy load or inodes created
415 during get_sb by a pseudo filesystem that directly
416 populates itself. */
417 spin_lock(&sbsec->isec_lock);
418next_inode:
419 if (!list_empty(&sbsec->isec_head)) {
420 struct inode_security_struct *isec =
421 list_entry(sbsec->isec_head.next,
422 struct inode_security_struct, list);
423 struct inode *inode = isec->inode;
424 spin_unlock(&sbsec->isec_lock);
425 inode = igrab(inode);
426 if (inode) {
427 if (!IS_PRIVATE(inode))
428 inode_doinit(inode);
429 iput(inode);
430 }
431 spin_lock(&sbsec->isec_lock);
432 list_del_init(&isec->list);
433 goto next_inode;
434 }
435 spin_unlock(&sbsec->isec_lock);
436out:
437 return rc;
438}
439
440/*
441 * This function should allow an FS to ask what it's mount security
442 * options were so it can use those later for submounts, displaying
443 * mount options, or whatever.
444 */
445static int selinux_get_mnt_opts(const struct super_block *sb,
446 struct security_mnt_opts *opts)
447{
448 int rc = 0, i;
449 struct superblock_security_struct *sbsec = sb->s_security;
450 char *context = NULL;
451 u32 len;
452 char tmp;
453
454 security_init_mnt_opts(opts);
455
456 if (!(sbsec->flags & SE_SBINITIALIZED))
457 return -EINVAL;
458
459 if (!ss_initialized)
460 return -EINVAL;
461
462 tmp = sbsec->flags & SE_MNTMASK;
463 /* count the number of mount options for this sb */
464 for (i = 0; i < 8; i++) {
465 if (tmp & 0x01)
466 opts->num_mnt_opts++;
467 tmp >>= 1;
468 }
469 /* Check if the Label support flag is set */
470 if (sbsec->flags & SE_SBLABELSUPP)
471 opts->num_mnt_opts++;
472
473 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474 if (!opts->mnt_opts) {
475 rc = -ENOMEM;
476 goto out_free;
477 }
478
479 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480 if (!opts->mnt_opts_flags) {
481 rc = -ENOMEM;
482 goto out_free;
483 }
484
485 i = 0;
486 if (sbsec->flags & FSCONTEXT_MNT) {
487 rc = security_sid_to_context(sbsec->sid, &context, &len);
488 if (rc)
489 goto out_free;
490 opts->mnt_opts[i] = context;
491 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492 }
493 if (sbsec->flags & CONTEXT_MNT) {
494 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495 if (rc)
496 goto out_free;
497 opts->mnt_opts[i] = context;
498 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499 }
500 if (sbsec->flags & DEFCONTEXT_MNT) {
501 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502 if (rc)
503 goto out_free;
504 opts->mnt_opts[i] = context;
505 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506 }
507 if (sbsec->flags & ROOTCONTEXT_MNT) {
508 struct inode *root = sbsec->sb->s_root->d_inode;
509 struct inode_security_struct *isec = root->i_security;
510
511 rc = security_sid_to_context(isec->sid, &context, &len);
512 if (rc)
513 goto out_free;
514 opts->mnt_opts[i] = context;
515 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516 }
517 if (sbsec->flags & SE_SBLABELSUPP) {
518 opts->mnt_opts[i] = NULL;
519 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520 }
521
522 BUG_ON(i != opts->num_mnt_opts);
523
524 return 0;
525
526out_free:
527 security_free_mnt_opts(opts);
528 return rc;
529}
530
531static int bad_option(struct superblock_security_struct *sbsec, char flag,
532 u32 old_sid, u32 new_sid)
533{
534 char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536 /* check if the old mount command had the same options */
537 if (sbsec->flags & SE_SBINITIALIZED)
538 if (!(sbsec->flags & flag) ||
539 (old_sid != new_sid))
540 return 1;
541
542 /* check if we were passed the same options twice,
543 * aka someone passed context=a,context=b
544 */
545 if (!(sbsec->flags & SE_SBINITIALIZED))
546 if (mnt_flags & flag)
547 return 1;
548 return 0;
549}
550
551/*
552 * Allow filesystems with binary mount data to explicitly set mount point
553 * labeling information.
554 */
555static int selinux_set_mnt_opts(struct super_block *sb,
556 struct security_mnt_opts *opts)
557{
558 const struct cred *cred = current_cred();
559 int rc = 0, i;
560 struct superblock_security_struct *sbsec = sb->s_security;
561 const char *name = sb->s_type->name;
562 struct inode *inode = sbsec->sb->s_root->d_inode;
563 struct inode_security_struct *root_isec = inode->i_security;
564 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565 u32 defcontext_sid = 0;
566 char **mount_options = opts->mnt_opts;
567 int *flags = opts->mnt_opts_flags;
568 int num_opts = opts->num_mnt_opts;
569
570 mutex_lock(&sbsec->lock);
571
572 if (!ss_initialized) {
573 if (!num_opts) {
574 /* Defer initialization until selinux_complete_init,
575 after the initial policy is loaded and the security
576 server is ready to handle calls. */
577 goto out;
578 }
579 rc = -EINVAL;
580 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581 "before the security server is initialized\n");
582 goto out;
583 }
584
585 /*
586 * Binary mount data FS will come through this function twice. Once
587 * from an explicit call and once from the generic calls from the vfs.
588 * Since the generic VFS calls will not contain any security mount data
589 * we need to skip the double mount verification.
590 *
591 * This does open a hole in which we will not notice if the first
592 * mount using this sb set explict options and a second mount using
593 * this sb does not set any security options. (The first options
594 * will be used for both mounts)
595 */
596 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597 && (num_opts == 0))
598 goto out;
599
600 /*
601 * parse the mount options, check if they are valid sids.
602 * also check if someone is trying to mount the same sb more
603 * than once with different security options.
604 */
605 for (i = 0; i < num_opts; i++) {
606 u32 sid;
607
608 if (flags[i] == SE_SBLABELSUPP)
609 continue;
610 rc = security_context_to_sid(mount_options[i],
611 strlen(mount_options[i]), &sid);
612 if (rc) {
613 printk(KERN_WARNING "SELinux: security_context_to_sid"
614 "(%s) failed for (dev %s, type %s) errno=%d\n",
615 mount_options[i], sb->s_id, name, rc);
616 goto out;
617 }
618 switch (flags[i]) {
619 case FSCONTEXT_MNT:
620 fscontext_sid = sid;
621
622 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623 fscontext_sid))
624 goto out_double_mount;
625
626 sbsec->flags |= FSCONTEXT_MNT;
627 break;
628 case CONTEXT_MNT:
629 context_sid = sid;
630
631 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632 context_sid))
633 goto out_double_mount;
634
635 sbsec->flags |= CONTEXT_MNT;
636 break;
637 case ROOTCONTEXT_MNT:
638 rootcontext_sid = sid;
639
640 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641 rootcontext_sid))
642 goto out_double_mount;
643
644 sbsec->flags |= ROOTCONTEXT_MNT;
645
646 break;
647 case DEFCONTEXT_MNT:
648 defcontext_sid = sid;
649
650 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651 defcontext_sid))
652 goto out_double_mount;
653
654 sbsec->flags |= DEFCONTEXT_MNT;
655
656 break;
657 default:
658 rc = -EINVAL;
659 goto out;
660 }
661 }
662
663 if (sbsec->flags & SE_SBINITIALIZED) {
664 /* previously mounted with options, but not on this attempt? */
665 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666 goto out_double_mount;
667 rc = 0;
668 goto out;
669 }
670
671 if (strcmp(sb->s_type->name, "proc") == 0)
672 sbsec->flags |= SE_SBPROC;
673
674 /* Determine the labeling behavior to use for this filesystem type. */
675 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676 if (rc) {
677 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678 __func__, sb->s_type->name, rc);
679 goto out;
680 }
681
682 /* sets the context of the superblock for the fs being mounted. */
683 if (fscontext_sid) {
684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685 if (rc)
686 goto out;
687
688 sbsec->sid = fscontext_sid;
689 }
690
691 /*
692 * Switch to using mount point labeling behavior.
693 * sets the label used on all file below the mountpoint, and will set
694 * the superblock context if not already set.
695 */
696 if (context_sid) {
697 if (!fscontext_sid) {
698 rc = may_context_mount_sb_relabel(context_sid, sbsec,
699 cred);
700 if (rc)
701 goto out;
702 sbsec->sid = context_sid;
703 } else {
704 rc = may_context_mount_inode_relabel(context_sid, sbsec,
705 cred);
706 if (rc)
707 goto out;
708 }
709 if (!rootcontext_sid)
710 rootcontext_sid = context_sid;
711
712 sbsec->mntpoint_sid = context_sid;
713 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714 }
715
716 if (rootcontext_sid) {
717 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718 cred);
719 if (rc)
720 goto out;
721
722 root_isec->sid = rootcontext_sid;
723 root_isec->initialized = 1;
724 }
725
726 if (defcontext_sid) {
727 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728 rc = -EINVAL;
729 printk(KERN_WARNING "SELinux: defcontext option is "
730 "invalid for this filesystem type\n");
731 goto out;
732 }
733
734 if (defcontext_sid != sbsec->def_sid) {
735 rc = may_context_mount_inode_relabel(defcontext_sid,
736 sbsec, cred);
737 if (rc)
738 goto out;
739 }
740
741 sbsec->def_sid = defcontext_sid;
742 }
743
744 rc = sb_finish_set_opts(sb);
745out:
746 mutex_unlock(&sbsec->lock);
747 return rc;
748out_double_mount:
749 rc = -EINVAL;
750 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
751 "security settings for (dev %s, type %s)\n", sb->s_id, name);
752 goto out;
753}
754
755static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756 struct super_block *newsb)
757{
758 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759 struct superblock_security_struct *newsbsec = newsb->s_security;
760
761 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
762 int set_context = (oldsbsec->flags & CONTEXT_MNT);
763 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765 /*
766 * if the parent was able to be mounted it clearly had no special lsm
767 * mount options. thus we can safely deal with this superblock later
768 */
769 if (!ss_initialized)
770 return;
771
772 /* how can we clone if the old one wasn't set up?? */
773 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775 /* if fs is reusing a sb, just let its options stand... */
776 if (newsbsec->flags & SE_SBINITIALIZED)
777 return;
778
779 mutex_lock(&newsbsec->lock);
780
781 newsbsec->flags = oldsbsec->flags;
782
783 newsbsec->sid = oldsbsec->sid;
784 newsbsec->def_sid = oldsbsec->def_sid;
785 newsbsec->behavior = oldsbsec->behavior;
786
787 if (set_context) {
788 u32 sid = oldsbsec->mntpoint_sid;
789
790 if (!set_fscontext)
791 newsbsec->sid = sid;
792 if (!set_rootcontext) {
793 struct inode *newinode = newsb->s_root->d_inode;
794 struct inode_security_struct *newisec = newinode->i_security;
795 newisec->sid = sid;
796 }
797 newsbsec->mntpoint_sid = sid;
798 }
799 if (set_rootcontext) {
800 const struct inode *oldinode = oldsb->s_root->d_inode;
801 const struct inode_security_struct *oldisec = oldinode->i_security;
802 struct inode *newinode = newsb->s_root->d_inode;
803 struct inode_security_struct *newisec = newinode->i_security;
804
805 newisec->sid = oldisec->sid;
806 }
807
808 sb_finish_set_opts(newsb);
809 mutex_unlock(&newsbsec->lock);
810}
811
812static int selinux_parse_opts_str(char *options,
813 struct security_mnt_opts *opts)
814{
815 char *p;
816 char *context = NULL, *defcontext = NULL;
817 char *fscontext = NULL, *rootcontext = NULL;
818 int rc, num_mnt_opts = 0;
819
820 opts->num_mnt_opts = 0;
821
822 /* Standard string-based options. */
823 while ((p = strsep(&options, "|")) != NULL) {
824 int token;
825 substring_t args[MAX_OPT_ARGS];
826
827 if (!*p)
828 continue;
829
830 token = match_token(p, tokens, args);
831
832 switch (token) {
833 case Opt_context:
834 if (context || defcontext) {
835 rc = -EINVAL;
836 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837 goto out_err;
838 }
839 context = match_strdup(&args[0]);
840 if (!context) {
841 rc = -ENOMEM;
842 goto out_err;
843 }
844 break;
845
846 case Opt_fscontext:
847 if (fscontext) {
848 rc = -EINVAL;
849 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850 goto out_err;
851 }
852 fscontext = match_strdup(&args[0]);
853 if (!fscontext) {
854 rc = -ENOMEM;
855 goto out_err;
856 }
857 break;
858
859 case Opt_rootcontext:
860 if (rootcontext) {
861 rc = -EINVAL;
862 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863 goto out_err;
864 }
865 rootcontext = match_strdup(&args[0]);
866 if (!rootcontext) {
867 rc = -ENOMEM;
868 goto out_err;
869 }
870 break;
871
872 case Opt_defcontext:
873 if (context || defcontext) {
874 rc = -EINVAL;
875 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876 goto out_err;
877 }
878 defcontext = match_strdup(&args[0]);
879 if (!defcontext) {
880 rc = -ENOMEM;
881 goto out_err;
882 }
883 break;
884 case Opt_labelsupport:
885 break;
886 default:
887 rc = -EINVAL;
888 printk(KERN_WARNING "SELinux: unknown mount option\n");
889 goto out_err;
890
891 }
892 }
893
894 rc = -ENOMEM;
895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896 if (!opts->mnt_opts)
897 goto out_err;
898
899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900 if (!opts->mnt_opts_flags) {
901 kfree(opts->mnt_opts);
902 goto out_err;
903 }
904
905 if (fscontext) {
906 opts->mnt_opts[num_mnt_opts] = fscontext;
907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 }
909 if (context) {
910 opts->mnt_opts[num_mnt_opts] = context;
911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 }
913 if (rootcontext) {
914 opts->mnt_opts[num_mnt_opts] = rootcontext;
915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 }
917 if (defcontext) {
918 opts->mnt_opts[num_mnt_opts] = defcontext;
919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 }
921
922 opts->num_mnt_opts = num_mnt_opts;
923 return 0;
924
925out_err:
926 kfree(context);
927 kfree(defcontext);
928 kfree(fscontext);
929 kfree(rootcontext);
930 return rc;
931}
932/*
933 * string mount options parsing and call set the sbsec
934 */
935static int superblock_doinit(struct super_block *sb, void *data)
936{
937 int rc = 0;
938 char *options = data;
939 struct security_mnt_opts opts;
940
941 security_init_mnt_opts(&opts);
942
943 if (!data)
944 goto out;
945
946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948 rc = selinux_parse_opts_str(options, &opts);
949 if (rc)
950 goto out_err;
951
952out:
953 rc = selinux_set_mnt_opts(sb, &opts);
954
955out_err:
956 security_free_mnt_opts(&opts);
957 return rc;
958}
959
960static void selinux_write_opts(struct seq_file *m,
961 struct security_mnt_opts *opts)
962{
963 int i;
964 char *prefix;
965
966 for (i = 0; i < opts->num_mnt_opts; i++) {
967 char *has_comma;
968
969 if (opts->mnt_opts[i])
970 has_comma = strchr(opts->mnt_opts[i], ',');
971 else
972 has_comma = NULL;
973
974 switch (opts->mnt_opts_flags[i]) {
975 case CONTEXT_MNT:
976 prefix = CONTEXT_STR;
977 break;
978 case FSCONTEXT_MNT:
979 prefix = FSCONTEXT_STR;
980 break;
981 case ROOTCONTEXT_MNT:
982 prefix = ROOTCONTEXT_STR;
983 break;
984 case DEFCONTEXT_MNT:
985 prefix = DEFCONTEXT_STR;
986 break;
987 case SE_SBLABELSUPP:
988 seq_putc(m, ',');
989 seq_puts(m, LABELSUPP_STR);
990 continue;
991 default:
992 BUG();
993 return;
994 };
995 /* we need a comma before each option */
996 seq_putc(m, ',');
997 seq_puts(m, prefix);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 seq_puts(m, opts->mnt_opts[i]);
1001 if (has_comma)
1002 seq_putc(m, '\"');
1003 }
1004}
1005
1006static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007{
1008 struct security_mnt_opts opts;
1009 int rc;
1010
1011 rc = selinux_get_mnt_opts(sb, &opts);
1012 if (rc) {
1013 /* before policy load we may get EINVAL, don't show anything */
1014 if (rc == -EINVAL)
1015 rc = 0;
1016 return rc;
1017 }
1018
1019 selinux_write_opts(m, &opts);
1020
1021 security_free_mnt_opts(&opts);
1022
1023 return rc;
1024}
1025
1026static inline u16 inode_mode_to_security_class(umode_t mode)
1027{
1028 switch (mode & S_IFMT) {
1029 case S_IFSOCK:
1030 return SECCLASS_SOCK_FILE;
1031 case S_IFLNK:
1032 return SECCLASS_LNK_FILE;
1033 case S_IFREG:
1034 return SECCLASS_FILE;
1035 case S_IFBLK:
1036 return SECCLASS_BLK_FILE;
1037 case S_IFDIR:
1038 return SECCLASS_DIR;
1039 case S_IFCHR:
1040 return SECCLASS_CHR_FILE;
1041 case S_IFIFO:
1042 return SECCLASS_FIFO_FILE;
1043
1044 }
1045
1046 return SECCLASS_FILE;
1047}
1048
1049static inline int default_protocol_stream(int protocol)
1050{
1051 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052}
1053
1054static inline int default_protocol_dgram(int protocol)
1055{
1056 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057}
1058
1059static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060{
1061 switch (family) {
1062 case PF_UNIX:
1063 switch (type) {
1064 case SOCK_STREAM:
1065 case SOCK_SEQPACKET:
1066 return SECCLASS_UNIX_STREAM_SOCKET;
1067 case SOCK_DGRAM:
1068 return SECCLASS_UNIX_DGRAM_SOCKET;
1069 }
1070 break;
1071 case PF_INET:
1072 case PF_INET6:
1073 switch (type) {
1074 case SOCK_STREAM:
1075 if (default_protocol_stream(protocol))
1076 return SECCLASS_TCP_SOCKET;
1077 else
1078 return SECCLASS_RAWIP_SOCKET;
1079 case SOCK_DGRAM:
1080 if (default_protocol_dgram(protocol))
1081 return SECCLASS_UDP_SOCKET;
1082 else
1083 return SECCLASS_RAWIP_SOCKET;
1084 case SOCK_DCCP:
1085 return SECCLASS_DCCP_SOCKET;
1086 default:
1087 return SECCLASS_RAWIP_SOCKET;
1088 }
1089 break;
1090 case PF_NETLINK:
1091 switch (protocol) {
1092 case NETLINK_ROUTE:
1093 return SECCLASS_NETLINK_ROUTE_SOCKET;
1094 case NETLINK_FIREWALL:
1095 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096 case NETLINK_INET_DIAG:
1097 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098 case NETLINK_NFLOG:
1099 return SECCLASS_NETLINK_NFLOG_SOCKET;
1100 case NETLINK_XFRM:
1101 return SECCLASS_NETLINK_XFRM_SOCKET;
1102 case NETLINK_SELINUX:
1103 return SECCLASS_NETLINK_SELINUX_SOCKET;
1104 case NETLINK_AUDIT:
1105 return SECCLASS_NETLINK_AUDIT_SOCKET;
1106 case NETLINK_IP6_FW:
1107 return SECCLASS_NETLINK_IP6FW_SOCKET;
1108 case NETLINK_DNRTMSG:
1109 return SECCLASS_NETLINK_DNRT_SOCKET;
1110 case NETLINK_KOBJECT_UEVENT:
1111 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112 default:
1113 return SECCLASS_NETLINK_SOCKET;
1114 }
1115 case PF_PACKET:
1116 return SECCLASS_PACKET_SOCKET;
1117 case PF_KEY:
1118 return SECCLASS_KEY_SOCKET;
1119 case PF_APPLETALK:
1120 return SECCLASS_APPLETALK_SOCKET;
1121 }
1122
1123 return SECCLASS_SOCKET;
1124}
1125
1126#ifdef CONFIG_PROC_FS
1127static int selinux_proc_get_sid(struct dentry *dentry,
1128 u16 tclass,
1129 u32 *sid)
1130{
1131 int rc;
1132 char *buffer, *path;
1133
1134 buffer = (char *)__get_free_page(GFP_KERNEL);
1135 if (!buffer)
1136 return -ENOMEM;
1137
1138 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139 if (IS_ERR(path))
1140 rc = PTR_ERR(path);
1141 else {
1142 /* each process gets a /proc/PID/ entry. Strip off the
1143 * PID part to get a valid selinux labeling.
1144 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145 while (path[1] >= '0' && path[1] <= '9') {
1146 path[1] = '/';
1147 path++;
1148 }
1149 rc = security_genfs_sid("proc", path, tclass, sid);
1150 }
1151 free_page((unsigned long)buffer);
1152 return rc;
1153}
1154#else
1155static int selinux_proc_get_sid(struct dentry *dentry,
1156 u16 tclass,
1157 u32 *sid)
1158{
1159 return -EINVAL;
1160}
1161#endif
1162
1163/* The inode's security attributes must be initialized before first use. */
1164static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165{
1166 struct superblock_security_struct *sbsec = NULL;
1167 struct inode_security_struct *isec = inode->i_security;
1168 u32 sid;
1169 struct dentry *dentry;
1170#define INITCONTEXTLEN 255
1171 char *context = NULL;
1172 unsigned len = 0;
1173 int rc = 0;
1174
1175 if (isec->initialized)
1176 goto out;
1177
1178 mutex_lock(&isec->lock);
1179 if (isec->initialized)
1180 goto out_unlock;
1181
1182 sbsec = inode->i_sb->s_security;
1183 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184 /* Defer initialization until selinux_complete_init,
1185 after the initial policy is loaded and the security
1186 server is ready to handle calls. */
1187 spin_lock(&sbsec->isec_lock);
1188 if (list_empty(&isec->list))
1189 list_add(&isec->list, &sbsec->isec_head);
1190 spin_unlock(&sbsec->isec_lock);
1191 goto out_unlock;
1192 }
1193
1194 switch (sbsec->behavior) {
1195 case SECURITY_FS_USE_XATTR:
1196 if (!inode->i_op->getxattr) {
1197 isec->sid = sbsec->def_sid;
1198 break;
1199 }
1200
1201 /* Need a dentry, since the xattr API requires one.
1202 Life would be simpler if we could just pass the inode. */
1203 if (opt_dentry) {
1204 /* Called from d_instantiate or d_splice_alias. */
1205 dentry = dget(opt_dentry);
1206 } else {
1207 /* Called from selinux_complete_init, try to find a dentry. */
1208 dentry = d_find_alias(inode);
1209 }
1210 if (!dentry) {
1211 /*
1212 * this is can be hit on boot when a file is accessed
1213 * before the policy is loaded. When we load policy we
1214 * may find inodes that have no dentry on the
1215 * sbsec->isec_head list. No reason to complain as these
1216 * will get fixed up the next time we go through
1217 * inode_doinit with a dentry, before these inodes could
1218 * be used again by userspace.
1219 */
1220 goto out_unlock;
1221 }
1222
1223 len = INITCONTEXTLEN;
1224 context = kmalloc(len+1, GFP_NOFS);
1225 if (!context) {
1226 rc = -ENOMEM;
1227 dput(dentry);
1228 goto out_unlock;
1229 }
1230 context[len] = '\0';
1231 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232 context, len);
1233 if (rc == -ERANGE) {
1234 kfree(context);
1235
1236 /* Need a larger buffer. Query for the right size. */
1237 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238 NULL, 0);
1239 if (rc < 0) {
1240 dput(dentry);
1241 goto out_unlock;
1242 }
1243 len = rc;
1244 context = kmalloc(len+1, GFP_NOFS);
1245 if (!context) {
1246 rc = -ENOMEM;
1247 dput(dentry);
1248 goto out_unlock;
1249 }
1250 context[len] = '\0';
1251 rc = inode->i_op->getxattr(dentry,
1252 XATTR_NAME_SELINUX,
1253 context, len);
1254 }
1255 dput(dentry);
1256 if (rc < 0) {
1257 if (rc != -ENODATA) {
1258 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1259 "%d for dev=%s ino=%ld\n", __func__,
1260 -rc, inode->i_sb->s_id, inode->i_ino);
1261 kfree(context);
1262 goto out_unlock;
1263 }
1264 /* Map ENODATA to the default file SID */
1265 sid = sbsec->def_sid;
1266 rc = 0;
1267 } else {
1268 rc = security_context_to_sid_default(context, rc, &sid,
1269 sbsec->def_sid,
1270 GFP_NOFS);
1271 if (rc) {
1272 char *dev = inode->i_sb->s_id;
1273 unsigned long ino = inode->i_ino;
1274
1275 if (rc == -EINVAL) {
1276 if (printk_ratelimit())
1277 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278 "context=%s. This indicates you may need to relabel the inode or the "
1279 "filesystem in question.\n", ino, dev, context);
1280 } else {
1281 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1282 "returned %d for dev=%s ino=%ld\n",
1283 __func__, context, -rc, dev, ino);
1284 }
1285 kfree(context);
1286 /* Leave with the unlabeled SID */
1287 rc = 0;
1288 break;
1289 }
1290 }
1291 kfree(context);
1292 isec->sid = sid;
1293 break;
1294 case SECURITY_FS_USE_TASK:
1295 isec->sid = isec->task_sid;
1296 break;
1297 case SECURITY_FS_USE_TRANS:
1298 /* Default to the fs SID. */
1299 isec->sid = sbsec->sid;
1300
1301 /* Try to obtain a transition SID. */
1302 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304 isec->sclass, NULL, &sid);
1305 if (rc)
1306 goto out_unlock;
1307 isec->sid = sid;
1308 break;
1309 case SECURITY_FS_USE_MNTPOINT:
1310 isec->sid = sbsec->mntpoint_sid;
1311 break;
1312 default:
1313 /* Default to the fs superblock SID. */
1314 isec->sid = sbsec->sid;
1315
1316 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317 if (opt_dentry) {
1318 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319 rc = selinux_proc_get_sid(opt_dentry,
1320 isec->sclass,
1321 &sid);
1322 if (rc)
1323 goto out_unlock;
1324 isec->sid = sid;
1325 }
1326 }
1327 break;
1328 }
1329
1330 isec->initialized = 1;
1331
1332out_unlock:
1333 mutex_unlock(&isec->lock);
1334out:
1335 if (isec->sclass == SECCLASS_FILE)
1336 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337 return rc;
1338}
1339
1340/* Convert a Linux signal to an access vector. */
1341static inline u32 signal_to_av(int sig)
1342{
1343 u32 perm = 0;
1344
1345 switch (sig) {
1346 case SIGCHLD:
1347 /* Commonly granted from child to parent. */
1348 perm = PROCESS__SIGCHLD;
1349 break;
1350 case SIGKILL:
1351 /* Cannot be caught or ignored */
1352 perm = PROCESS__SIGKILL;
1353 break;
1354 case SIGSTOP:
1355 /* Cannot be caught or ignored */
1356 perm = PROCESS__SIGSTOP;
1357 break;
1358 default:
1359 /* All other signals. */
1360 perm = PROCESS__SIGNAL;
1361 break;
1362 }
1363
1364 return perm;
1365}
1366
1367/*
1368 * Check permission between a pair of credentials
1369 * fork check, ptrace check, etc.
1370 */
1371static int cred_has_perm(const struct cred *actor,
1372 const struct cred *target,
1373 u32 perms)
1374{
1375 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378}
1379
1380/*
1381 * Check permission between a pair of tasks, e.g. signal checks,
1382 * fork check, ptrace check, etc.
1383 * tsk1 is the actor and tsk2 is the target
1384 * - this uses the default subjective creds of tsk1
1385 */
1386static int task_has_perm(const struct task_struct *tsk1,
1387 const struct task_struct *tsk2,
1388 u32 perms)
1389{
1390 const struct task_security_struct *__tsec1, *__tsec2;
1391 u32 sid1, sid2;
1392
1393 rcu_read_lock();
1394 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1395 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1396 rcu_read_unlock();
1397 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398}
1399
1400/*
1401 * Check permission between current and another task, e.g. signal checks,
1402 * fork check, ptrace check, etc.
1403 * current is the actor and tsk2 is the target
1404 * - this uses current's subjective creds
1405 */
1406static int current_has_perm(const struct task_struct *tsk,
1407 u32 perms)
1408{
1409 u32 sid, tsid;
1410
1411 sid = current_sid();
1412 tsid = task_sid(tsk);
1413 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414}
1415
1416#if CAP_LAST_CAP > 63
1417#error Fix SELinux to handle capabilities > 63.
1418#endif
1419
1420/* Check whether a task is allowed to use a capability. */
1421static int task_has_capability(struct task_struct *tsk,
1422 const struct cred *cred,
1423 int cap, int audit)
1424{
1425 struct common_audit_data ad;
1426 struct av_decision avd;
1427 u16 sclass;
1428 u32 sid = cred_sid(cred);
1429 u32 av = CAP_TO_MASK(cap);
1430 int rc;
1431
1432 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433 ad.tsk = tsk;
1434 ad.u.cap = cap;
1435
1436 switch (CAP_TO_INDEX(cap)) {
1437 case 0:
1438 sclass = SECCLASS_CAPABILITY;
1439 break;
1440 case 1:
1441 sclass = SECCLASS_CAPABILITY2;
1442 break;
1443 default:
1444 printk(KERN_ERR
1445 "SELinux: out of range capability %d\n", cap);
1446 BUG();
1447 return -EINVAL;
1448 }
1449
1450 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451 if (audit == SECURITY_CAP_AUDIT) {
1452 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453 if (rc2)
1454 return rc2;
1455 }
1456 return rc;
1457}
1458
1459/* Check whether a task is allowed to use a system operation. */
1460static int task_has_system(struct task_struct *tsk,
1461 u32 perms)
1462{
1463 u32 sid = task_sid(tsk);
1464
1465 return avc_has_perm(sid, SECINITSID_KERNEL,
1466 SECCLASS_SYSTEM, perms, NULL);
1467}
1468
1469/* Check whether a task has a particular permission to an inode.
1470 The 'adp' parameter is optional and allows other audit
1471 data to be passed (e.g. the dentry). */
1472static int inode_has_perm(const struct cred *cred,
1473 struct inode *inode,
1474 u32 perms,
1475 struct common_audit_data *adp,
1476 unsigned flags)
1477{
1478 struct inode_security_struct *isec;
1479 u32 sid;
1480
1481 validate_creds(cred);
1482
1483 if (unlikely(IS_PRIVATE(inode)))
1484 return 0;
1485
1486 sid = cred_sid(cred);
1487 isec = inode->i_security;
1488
1489 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1490}
1491
1492static int inode_has_perm_noadp(const struct cred *cred,
1493 struct inode *inode,
1494 u32 perms,
1495 unsigned flags)
1496{
1497 struct common_audit_data ad;
1498
1499 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500 ad.u.inode = inode;
1501 return inode_has_perm(cred, inode, perms, &ad, flags);
1502}
1503
1504/* Same as inode_has_perm, but pass explicit audit data containing
1505 the dentry to help the auditing code to more easily generate the
1506 pathname if needed. */
1507static inline int dentry_has_perm(const struct cred *cred,
1508 struct dentry *dentry,
1509 u32 av)
1510{
1511 struct inode *inode = dentry->d_inode;
1512 struct common_audit_data ad;
1513
1514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1515 ad.u.dentry = dentry;
1516 return inode_has_perm(cred, inode, av, &ad, 0);
1517}
1518
1519/* Same as inode_has_perm, but pass explicit audit data containing
1520 the path to help the auditing code to more easily generate the
1521 pathname if needed. */
1522static inline int path_has_perm(const struct cred *cred,
1523 struct path *path,
1524 u32 av)
1525{
1526 struct inode *inode = path->dentry->d_inode;
1527 struct common_audit_data ad;
1528
1529 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1530 ad.u.path = *path;
1531 return inode_has_perm(cred, inode, av, &ad, 0);
1532}
1533
1534/* Check whether a task can use an open file descriptor to
1535 access an inode in a given way. Check access to the
1536 descriptor itself, and then use dentry_has_perm to
1537 check a particular permission to the file.
1538 Access to the descriptor is implicitly granted if it
1539 has the same SID as the process. If av is zero, then
1540 access to the file is not checked, e.g. for cases
1541 where only the descriptor is affected like seek. */
1542static int file_has_perm(const struct cred *cred,
1543 struct file *file,
1544 u32 av)
1545{
1546 struct file_security_struct *fsec = file->f_security;
1547 struct inode *inode = file->f_path.dentry->d_inode;
1548 struct common_audit_data ad;
1549 u32 sid = cred_sid(cred);
1550 int rc;
1551
1552 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1553 ad.u.path = file->f_path;
1554
1555 if (sid != fsec->sid) {
1556 rc = avc_has_perm(sid, fsec->sid,
1557 SECCLASS_FD,
1558 FD__USE,
1559 &ad);
1560 if (rc)
1561 goto out;
1562 }
1563
1564 /* av is zero if only checking access to the descriptor. */
1565 rc = 0;
1566 if (av)
1567 rc = inode_has_perm(cred, inode, av, &ad, 0);
1568
1569out:
1570 return rc;
1571}
1572
1573/* Check whether a task can create a file. */
1574static int may_create(struct inode *dir,
1575 struct dentry *dentry,
1576 u16 tclass)
1577{
1578 const struct task_security_struct *tsec = current_security();
1579 struct inode_security_struct *dsec;
1580 struct superblock_security_struct *sbsec;
1581 u32 sid, newsid;
1582 struct common_audit_data ad;
1583 int rc;
1584
1585 dsec = dir->i_security;
1586 sbsec = dir->i_sb->s_security;
1587
1588 sid = tsec->sid;
1589 newsid = tsec->create_sid;
1590
1591 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1592 ad.u.dentry = dentry;
1593
1594 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1595 DIR__ADD_NAME | DIR__SEARCH,
1596 &ad);
1597 if (rc)
1598 return rc;
1599
1600 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601 rc = security_transition_sid(sid, dsec->sid, tclass,
1602 &dentry->d_name, &newsid);
1603 if (rc)
1604 return rc;
1605 }
1606
1607 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1608 if (rc)
1609 return rc;
1610
1611 return avc_has_perm(newsid, sbsec->sid,
1612 SECCLASS_FILESYSTEM,
1613 FILESYSTEM__ASSOCIATE, &ad);
1614}
1615
1616/* Check whether a task can create a key. */
1617static int may_create_key(u32 ksid,
1618 struct task_struct *ctx)
1619{
1620 u32 sid = task_sid(ctx);
1621
1622 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623}
1624
1625#define MAY_LINK 0
1626#define MAY_UNLINK 1
1627#define MAY_RMDIR 2
1628
1629/* Check whether a task can link, unlink, or rmdir a file/directory. */
1630static int may_link(struct inode *dir,
1631 struct dentry *dentry,
1632 int kind)
1633
1634{
1635 struct inode_security_struct *dsec, *isec;
1636 struct common_audit_data ad;
1637 u32 sid = current_sid();
1638 u32 av;
1639 int rc;
1640
1641 dsec = dir->i_security;
1642 isec = dentry->d_inode->i_security;
1643
1644 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1645 ad.u.dentry = dentry;
1646
1647 av = DIR__SEARCH;
1648 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1650 if (rc)
1651 return rc;
1652
1653 switch (kind) {
1654 case MAY_LINK:
1655 av = FILE__LINK;
1656 break;
1657 case MAY_UNLINK:
1658 av = FILE__UNLINK;
1659 break;
1660 case MAY_RMDIR:
1661 av = DIR__RMDIR;
1662 break;
1663 default:
1664 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1665 __func__, kind);
1666 return 0;
1667 }
1668
1669 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1670 return rc;
1671}
1672
1673static inline int may_rename(struct inode *old_dir,
1674 struct dentry *old_dentry,
1675 struct inode *new_dir,
1676 struct dentry *new_dentry)
1677{
1678 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1679 struct common_audit_data ad;
1680 u32 sid = current_sid();
1681 u32 av;
1682 int old_is_dir, new_is_dir;
1683 int rc;
1684
1685 old_dsec = old_dir->i_security;
1686 old_isec = old_dentry->d_inode->i_security;
1687 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1688 new_dsec = new_dir->i_security;
1689
1690 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1691
1692 ad.u.dentry = old_dentry;
1693 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1694 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1695 if (rc)
1696 return rc;
1697 rc = avc_has_perm(sid, old_isec->sid,
1698 old_isec->sclass, FILE__RENAME, &ad);
1699 if (rc)
1700 return rc;
1701 if (old_is_dir && new_dir != old_dir) {
1702 rc = avc_has_perm(sid, old_isec->sid,
1703 old_isec->sclass, DIR__REPARENT, &ad);
1704 if (rc)
1705 return rc;
1706 }
1707
1708 ad.u.dentry = new_dentry;
1709 av = DIR__ADD_NAME | DIR__SEARCH;
1710 if (new_dentry->d_inode)
1711 av |= DIR__REMOVE_NAME;
1712 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1713 if (rc)
1714 return rc;
1715 if (new_dentry->d_inode) {
1716 new_isec = new_dentry->d_inode->i_security;
1717 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1718 rc = avc_has_perm(sid, new_isec->sid,
1719 new_isec->sclass,
1720 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1721 if (rc)
1722 return rc;
1723 }
1724
1725 return 0;
1726}
1727
1728/* Check whether a task can perform a filesystem operation. */
1729static int superblock_has_perm(const struct cred *cred,
1730 struct super_block *sb,
1731 u32 perms,
1732 struct common_audit_data *ad)
1733{
1734 struct superblock_security_struct *sbsec;
1735 u32 sid = cred_sid(cred);
1736
1737 sbsec = sb->s_security;
1738 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1739}
1740
1741/* Convert a Linux mode and permission mask to an access vector. */
1742static inline u32 file_mask_to_av(int mode, int mask)
1743{
1744 u32 av = 0;
1745
1746 if ((mode & S_IFMT) != S_IFDIR) {
1747 if (mask & MAY_EXEC)
1748 av |= FILE__EXECUTE;
1749 if (mask & MAY_READ)
1750 av |= FILE__READ;
1751
1752 if (mask & MAY_APPEND)
1753 av |= FILE__APPEND;
1754 else if (mask & MAY_WRITE)
1755 av |= FILE__WRITE;
1756
1757 } else {
1758 if (mask & MAY_EXEC)
1759 av |= DIR__SEARCH;
1760 if (mask & MAY_WRITE)
1761 av |= DIR__WRITE;
1762 if (mask & MAY_READ)
1763 av |= DIR__READ;
1764 }
1765
1766 return av;
1767}
1768
1769/* Convert a Linux file to an access vector. */
1770static inline u32 file_to_av(struct file *file)
1771{
1772 u32 av = 0;
1773
1774 if (file->f_mode & FMODE_READ)
1775 av |= FILE__READ;
1776 if (file->f_mode & FMODE_WRITE) {
1777 if (file->f_flags & O_APPEND)
1778 av |= FILE__APPEND;
1779 else
1780 av |= FILE__WRITE;
1781 }
1782 if (!av) {
1783 /*
1784 * Special file opened with flags 3 for ioctl-only use.
1785 */
1786 av = FILE__IOCTL;
1787 }
1788
1789 return av;
1790}
1791
1792/*
1793 * Convert a file to an access vector and include the correct open
1794 * open permission.
1795 */
1796static inline u32 open_file_to_av(struct file *file)
1797{
1798 u32 av = file_to_av(file);
1799
1800 if (selinux_policycap_openperm)
1801 av |= FILE__OPEN;
1802
1803 return av;
1804}
1805
1806/* Hook functions begin here. */
1807
1808static int selinux_ptrace_access_check(struct task_struct *child,
1809 unsigned int mode)
1810{
1811 int rc;
1812
1813 rc = cap_ptrace_access_check(child, mode);
1814 if (rc)
1815 return rc;
1816
1817 if (mode == PTRACE_MODE_READ) {
1818 u32 sid = current_sid();
1819 u32 csid = task_sid(child);
1820 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821 }
1822
1823 return current_has_perm(child, PROCESS__PTRACE);
1824}
1825
1826static int selinux_ptrace_traceme(struct task_struct *parent)
1827{
1828 int rc;
1829
1830 rc = cap_ptrace_traceme(parent);
1831 if (rc)
1832 return rc;
1833
1834 return task_has_perm(parent, current, PROCESS__PTRACE);
1835}
1836
1837static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839{
1840 int error;
1841
1842 error = current_has_perm(target, PROCESS__GETCAP);
1843 if (error)
1844 return error;
1845
1846 return cap_capget(target, effective, inheritable, permitted);
1847}
1848
1849static int selinux_capset(struct cred *new, const struct cred *old,
1850 const kernel_cap_t *effective,
1851 const kernel_cap_t *inheritable,
1852 const kernel_cap_t *permitted)
1853{
1854 int error;
1855
1856 error = cap_capset(new, old,
1857 effective, inheritable, permitted);
1858 if (error)
1859 return error;
1860
1861 return cred_has_perm(old, new, PROCESS__SETCAP);
1862}
1863
1864/*
1865 * (This comment used to live with the selinux_task_setuid hook,
1866 * which was removed).
1867 *
1868 * Since setuid only affects the current process, and since the SELinux
1869 * controls are not based on the Linux identity attributes, SELinux does not
1870 * need to control this operation. However, SELinux does control the use of
1871 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872 */
1873
1874static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875 struct user_namespace *ns, int cap, int audit)
1876{
1877 int rc;
1878
1879 rc = cap_capable(tsk, cred, ns, cap, audit);
1880 if (rc)
1881 return rc;
1882
1883 return task_has_capability(tsk, cred, cap, audit);
1884}
1885
1886static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1887{
1888 const struct cred *cred = current_cred();
1889 int rc = 0;
1890
1891 if (!sb)
1892 return 0;
1893
1894 switch (cmds) {
1895 case Q_SYNC:
1896 case Q_QUOTAON:
1897 case Q_QUOTAOFF:
1898 case Q_SETINFO:
1899 case Q_SETQUOTA:
1900 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901 break;
1902 case Q_GETFMT:
1903 case Q_GETINFO:
1904 case Q_GETQUOTA:
1905 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906 break;
1907 default:
1908 rc = 0; /* let the kernel handle invalid cmds */
1909 break;
1910 }
1911 return rc;
1912}
1913
1914static int selinux_quota_on(struct dentry *dentry)
1915{
1916 const struct cred *cred = current_cred();
1917
1918 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1919}
1920
1921static int selinux_syslog(int type)
1922{
1923 int rc;
1924
1925 switch (type) {
1926 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1927 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1928 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929 break;
1930 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1931 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1932 /* Set level of messages printed to console */
1933 case SYSLOG_ACTION_CONSOLE_LEVEL:
1934 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1935 break;
1936 case SYSLOG_ACTION_CLOSE: /* Close log */
1937 case SYSLOG_ACTION_OPEN: /* Open log */
1938 case SYSLOG_ACTION_READ: /* Read from log */
1939 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1940 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1941 default:
1942 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1943 break;
1944 }
1945 return rc;
1946}
1947
1948/*
1949 * Check that a process has enough memory to allocate a new virtual
1950 * mapping. 0 means there is enough memory for the allocation to
1951 * succeed and -ENOMEM implies there is not.
1952 *
1953 * Do not audit the selinux permission check, as this is applied to all
1954 * processes that allocate mappings.
1955 */
1956static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1957{
1958 int rc, cap_sys_admin = 0;
1959
1960 rc = selinux_capable(current, current_cred(),
1961 &init_user_ns, CAP_SYS_ADMIN,
1962 SECURITY_CAP_NOAUDIT);
1963 if (rc == 0)
1964 cap_sys_admin = 1;
1965
1966 return __vm_enough_memory(mm, pages, cap_sys_admin);
1967}
1968
1969/* binprm security operations */
1970
1971static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1972{
1973 const struct task_security_struct *old_tsec;
1974 struct task_security_struct *new_tsec;
1975 struct inode_security_struct *isec;
1976 struct common_audit_data ad;
1977 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1978 int rc;
1979
1980 rc = cap_bprm_set_creds(bprm);
1981 if (rc)
1982 return rc;
1983
1984 /* SELinux context only depends on initial program or script and not
1985 * the script interpreter */
1986 if (bprm->cred_prepared)
1987 return 0;
1988
1989 old_tsec = current_security();
1990 new_tsec = bprm->cred->security;
1991 isec = inode->i_security;
1992
1993 /* Default to the current task SID. */
1994 new_tsec->sid = old_tsec->sid;
1995 new_tsec->osid = old_tsec->sid;
1996
1997 /* Reset fs, key, and sock SIDs on execve. */
1998 new_tsec->create_sid = 0;
1999 new_tsec->keycreate_sid = 0;
2000 new_tsec->sockcreate_sid = 0;
2001
2002 if (old_tsec->exec_sid) {
2003 new_tsec->sid = old_tsec->exec_sid;
2004 /* Reset exec SID on execve. */
2005 new_tsec->exec_sid = 0;
2006 } else {
2007 /* Check for a default transition on this program. */
2008 rc = security_transition_sid(old_tsec->sid, isec->sid,
2009 SECCLASS_PROCESS, NULL,
2010 &new_tsec->sid);
2011 if (rc)
2012 return rc;
2013 }
2014
2015 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2016 ad.u.path = bprm->file->f_path;
2017
2018 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019 new_tsec->sid = old_tsec->sid;
2020
2021 if (new_tsec->sid == old_tsec->sid) {
2022 rc = avc_has_perm(old_tsec->sid, isec->sid,
2023 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2024 if (rc)
2025 return rc;
2026 } else {
2027 /* Check permissions for the transition. */
2028 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2029 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2030 if (rc)
2031 return rc;
2032
2033 rc = avc_has_perm(new_tsec->sid, isec->sid,
2034 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2035 if (rc)
2036 return rc;
2037
2038 /* Check for shared state */
2039 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2040 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2041 SECCLASS_PROCESS, PROCESS__SHARE,
2042 NULL);
2043 if (rc)
2044 return -EPERM;
2045 }
2046
2047 /* Make sure that anyone attempting to ptrace over a task that
2048 * changes its SID has the appropriate permit */
2049 if (bprm->unsafe &
2050 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2051 struct task_struct *tracer;
2052 struct task_security_struct *sec;
2053 u32 ptsid = 0;
2054
2055 rcu_read_lock();
2056 tracer = ptrace_parent(current);
2057 if (likely(tracer != NULL)) {
2058 sec = __task_cred(tracer)->security;
2059 ptsid = sec->sid;
2060 }
2061 rcu_read_unlock();
2062
2063 if (ptsid != 0) {
2064 rc = avc_has_perm(ptsid, new_tsec->sid,
2065 SECCLASS_PROCESS,
2066 PROCESS__PTRACE, NULL);
2067 if (rc)
2068 return -EPERM;
2069 }
2070 }
2071
2072 /* Clear any possibly unsafe personality bits on exec: */
2073 bprm->per_clear |= PER_CLEAR_ON_SETID;
2074 }
2075
2076 return 0;
2077}
2078
2079static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2080{
2081 const struct task_security_struct *tsec = current_security();
2082 u32 sid, osid;
2083 int atsecure = 0;
2084
2085 sid = tsec->sid;
2086 osid = tsec->osid;
2087
2088 if (osid != sid) {
2089 /* Enable secure mode for SIDs transitions unless
2090 the noatsecure permission is granted between
2091 the two SIDs, i.e. ahp returns 0. */
2092 atsecure = avc_has_perm(osid, sid,
2093 SECCLASS_PROCESS,
2094 PROCESS__NOATSECURE, NULL);
2095 }
2096
2097 return (atsecure || cap_bprm_secureexec(bprm));
2098}
2099
2100extern struct vfsmount *selinuxfs_mount;
2101extern struct dentry *selinux_null;
2102
2103/* Derived from fs/exec.c:flush_old_files. */
2104static inline void flush_unauthorized_files(const struct cred *cred,
2105 struct files_struct *files)
2106{
2107 struct common_audit_data ad;
2108 struct file *file, *devnull = NULL;
2109 struct tty_struct *tty;
2110 struct fdtable *fdt;
2111 long j = -1;
2112 int drop_tty = 0;
2113
2114 tty = get_current_tty();
2115 if (tty) {
2116 spin_lock(&tty_files_lock);
2117 if (!list_empty(&tty->tty_files)) {
2118 struct tty_file_private *file_priv;
2119 struct inode *inode;
2120
2121 /* Revalidate access to controlling tty.
2122 Use inode_has_perm on the tty inode directly rather
2123 than using file_has_perm, as this particular open
2124 file may belong to another process and we are only
2125 interested in the inode-based check here. */
2126 file_priv = list_first_entry(&tty->tty_files,
2127 struct tty_file_private, list);
2128 file = file_priv->file;
2129 inode = file->f_path.dentry->d_inode;
2130 if (inode_has_perm_noadp(cred, inode,
2131 FILE__READ | FILE__WRITE, 0)) {
2132 drop_tty = 1;
2133 }
2134 }
2135 spin_unlock(&tty_files_lock);
2136 tty_kref_put(tty);
2137 }
2138 /* Reset controlling tty. */
2139 if (drop_tty)
2140 no_tty();
2141
2142 /* Revalidate access to inherited open files. */
2143
2144 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2145
2146 spin_lock(&files->file_lock);
2147 for (;;) {
2148 unsigned long set, i;
2149 int fd;
2150
2151 j++;
2152 i = j * __NFDBITS;
2153 fdt = files_fdtable(files);
2154 if (i >= fdt->max_fds)
2155 break;
2156 set = fdt->open_fds->fds_bits[j];
2157 if (!set)
2158 continue;
2159 spin_unlock(&files->file_lock);
2160 for ( ; set ; i++, set >>= 1) {
2161 if (set & 1) {
2162 file = fget(i);
2163 if (!file)
2164 continue;
2165 if (file_has_perm(cred,
2166 file,
2167 file_to_av(file))) {
2168 sys_close(i);
2169 fd = get_unused_fd();
2170 if (fd != i) {
2171 if (fd >= 0)
2172 put_unused_fd(fd);
2173 fput(file);
2174 continue;
2175 }
2176 if (devnull) {
2177 get_file(devnull);
2178 } else {
2179 devnull = dentry_open(
2180 dget(selinux_null),
2181 mntget(selinuxfs_mount),
2182 O_RDWR, cred);
2183 if (IS_ERR(devnull)) {
2184 devnull = NULL;
2185 put_unused_fd(fd);
2186 fput(file);
2187 continue;
2188 }
2189 }
2190 fd_install(fd, devnull);
2191 }
2192 fput(file);
2193 }
2194 }
2195 spin_lock(&files->file_lock);
2196
2197 }
2198 spin_unlock(&files->file_lock);
2199}
2200
2201/*
2202 * Prepare a process for imminent new credential changes due to exec
2203 */
2204static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2205{
2206 struct task_security_struct *new_tsec;
2207 struct rlimit *rlim, *initrlim;
2208 int rc, i;
2209
2210 new_tsec = bprm->cred->security;
2211 if (new_tsec->sid == new_tsec->osid)
2212 return;
2213
2214 /* Close files for which the new task SID is not authorized. */
2215 flush_unauthorized_files(bprm->cred, current->files);
2216
2217 /* Always clear parent death signal on SID transitions. */
2218 current->pdeath_signal = 0;
2219
2220 /* Check whether the new SID can inherit resource limits from the old
2221 * SID. If not, reset all soft limits to the lower of the current
2222 * task's hard limit and the init task's soft limit.
2223 *
2224 * Note that the setting of hard limits (even to lower them) can be
2225 * controlled by the setrlimit check. The inclusion of the init task's
2226 * soft limit into the computation is to avoid resetting soft limits
2227 * higher than the default soft limit for cases where the default is
2228 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2229 */
2230 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2231 PROCESS__RLIMITINH, NULL);
2232 if (rc) {
2233 /* protect against do_prlimit() */
2234 task_lock(current);
2235 for (i = 0; i < RLIM_NLIMITS; i++) {
2236 rlim = current->signal->rlim + i;
2237 initrlim = init_task.signal->rlim + i;
2238 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2239 }
2240 task_unlock(current);
2241 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2242 }
2243}
2244
2245/*
2246 * Clean up the process immediately after the installation of new credentials
2247 * due to exec
2248 */
2249static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2250{
2251 const struct task_security_struct *tsec = current_security();
2252 struct itimerval itimer;
2253 u32 osid, sid;
2254 int rc, i;
2255
2256 osid = tsec->osid;
2257 sid = tsec->sid;
2258
2259 if (sid == osid)
2260 return;
2261
2262 /* Check whether the new SID can inherit signal state from the old SID.
2263 * If not, clear itimers to avoid subsequent signal generation and
2264 * flush and unblock signals.
2265 *
2266 * This must occur _after_ the task SID has been updated so that any
2267 * kill done after the flush will be checked against the new SID.
2268 */
2269 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2270 if (rc) {
2271 memset(&itimer, 0, sizeof itimer);
2272 for (i = 0; i < 3; i++)
2273 do_setitimer(i, &itimer, NULL);
2274 spin_lock_irq(¤t->sighand->siglock);
2275 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2276 __flush_signals(current);
2277 flush_signal_handlers(current, 1);
2278 sigemptyset(¤t->blocked);
2279 }
2280 spin_unlock_irq(¤t->sighand->siglock);
2281 }
2282
2283 /* Wake up the parent if it is waiting so that it can recheck
2284 * wait permission to the new task SID. */
2285 read_lock(&tasklist_lock);
2286 __wake_up_parent(current, current->real_parent);
2287 read_unlock(&tasklist_lock);
2288}
2289
2290/* superblock security operations */
2291
2292static int selinux_sb_alloc_security(struct super_block *sb)
2293{
2294 return superblock_alloc_security(sb);
2295}
2296
2297static void selinux_sb_free_security(struct super_block *sb)
2298{
2299 superblock_free_security(sb);
2300}
2301
2302static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2303{
2304 if (plen > olen)
2305 return 0;
2306
2307 return !memcmp(prefix, option, plen);
2308}
2309
2310static inline int selinux_option(char *option, int len)
2311{
2312 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2313 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2314 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2315 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2316 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2317}
2318
2319static inline void take_option(char **to, char *from, int *first, int len)
2320{
2321 if (!*first) {
2322 **to = ',';
2323 *to += 1;
2324 } else
2325 *first = 0;
2326 memcpy(*to, from, len);
2327 *to += len;
2328}
2329
2330static inline void take_selinux_option(char **to, char *from, int *first,
2331 int len)
2332{
2333 int current_size = 0;
2334
2335 if (!*first) {
2336 **to = '|';
2337 *to += 1;
2338 } else
2339 *first = 0;
2340
2341 while (current_size < len) {
2342 if (*from != '"') {
2343 **to = *from;
2344 *to += 1;
2345 }
2346 from += 1;
2347 current_size += 1;
2348 }
2349}
2350
2351static int selinux_sb_copy_data(char *orig, char *copy)
2352{
2353 int fnosec, fsec, rc = 0;
2354 char *in_save, *in_curr, *in_end;
2355 char *sec_curr, *nosec_save, *nosec;
2356 int open_quote = 0;
2357
2358 in_curr = orig;
2359 sec_curr = copy;
2360
2361 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2362 if (!nosec) {
2363 rc = -ENOMEM;
2364 goto out;
2365 }
2366
2367 nosec_save = nosec;
2368 fnosec = fsec = 1;
2369 in_save = in_end = orig;
2370
2371 do {
2372 if (*in_end == '"')
2373 open_quote = !open_quote;
2374 if ((*in_end == ',' && open_quote == 0) ||
2375 *in_end == '\0') {
2376 int len = in_end - in_curr;
2377
2378 if (selinux_option(in_curr, len))
2379 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2380 else
2381 take_option(&nosec, in_curr, &fnosec, len);
2382
2383 in_curr = in_end + 1;
2384 }
2385 } while (*in_end++);
2386
2387 strcpy(in_save, nosec_save);
2388 free_page((unsigned long)nosec_save);
2389out:
2390 return rc;
2391}
2392
2393static int selinux_sb_remount(struct super_block *sb, void *data)
2394{
2395 int rc, i, *flags;
2396 struct security_mnt_opts opts;
2397 char *secdata, **mount_options;
2398 struct superblock_security_struct *sbsec = sb->s_security;
2399
2400 if (!(sbsec->flags & SE_SBINITIALIZED))
2401 return 0;
2402
2403 if (!data)
2404 return 0;
2405
2406 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2407 return 0;
2408
2409 security_init_mnt_opts(&opts);
2410 secdata = alloc_secdata();
2411 if (!secdata)
2412 return -ENOMEM;
2413 rc = selinux_sb_copy_data(data, secdata);
2414 if (rc)
2415 goto out_free_secdata;
2416
2417 rc = selinux_parse_opts_str(secdata, &opts);
2418 if (rc)
2419 goto out_free_secdata;
2420
2421 mount_options = opts.mnt_opts;
2422 flags = opts.mnt_opts_flags;
2423
2424 for (i = 0; i < opts.num_mnt_opts; i++) {
2425 u32 sid;
2426 size_t len;
2427
2428 if (flags[i] == SE_SBLABELSUPP)
2429 continue;
2430 len = strlen(mount_options[i]);
2431 rc = security_context_to_sid(mount_options[i], len, &sid);
2432 if (rc) {
2433 printk(KERN_WARNING "SELinux: security_context_to_sid"
2434 "(%s) failed for (dev %s, type %s) errno=%d\n",
2435 mount_options[i], sb->s_id, sb->s_type->name, rc);
2436 goto out_free_opts;
2437 }
2438 rc = -EINVAL;
2439 switch (flags[i]) {
2440 case FSCONTEXT_MNT:
2441 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2442 goto out_bad_option;
2443 break;
2444 case CONTEXT_MNT:
2445 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2446 goto out_bad_option;
2447 break;
2448 case ROOTCONTEXT_MNT: {
2449 struct inode_security_struct *root_isec;
2450 root_isec = sb->s_root->d_inode->i_security;
2451
2452 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2453 goto out_bad_option;
2454 break;
2455 }
2456 case DEFCONTEXT_MNT:
2457 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2458 goto out_bad_option;
2459 break;
2460 default:
2461 goto out_free_opts;
2462 }
2463 }
2464
2465 rc = 0;
2466out_free_opts:
2467 security_free_mnt_opts(&opts);
2468out_free_secdata:
2469 free_secdata(secdata);
2470 return rc;
2471out_bad_option:
2472 printk(KERN_WARNING "SELinux: unable to change security options "
2473 "during remount (dev %s, type=%s)\n", sb->s_id,
2474 sb->s_type->name);
2475 goto out_free_opts;
2476}
2477
2478static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2479{
2480 const struct cred *cred = current_cred();
2481 struct common_audit_data ad;
2482 int rc;
2483
2484 rc = superblock_doinit(sb, data);
2485 if (rc)
2486 return rc;
2487
2488 /* Allow all mounts performed by the kernel */
2489 if (flags & MS_KERNMOUNT)
2490 return 0;
2491
2492 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2493 ad.u.dentry = sb->s_root;
2494 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2495}
2496
2497static int selinux_sb_statfs(struct dentry *dentry)
2498{
2499 const struct cred *cred = current_cred();
2500 struct common_audit_data ad;
2501
2502 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2503 ad.u.dentry = dentry->d_sb->s_root;
2504 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2505}
2506
2507static int selinux_mount(char *dev_name,
2508 struct path *path,
2509 char *type,
2510 unsigned long flags,
2511 void *data)
2512{
2513 const struct cred *cred = current_cred();
2514
2515 if (flags & MS_REMOUNT)
2516 return superblock_has_perm(cred, path->mnt->mnt_sb,
2517 FILESYSTEM__REMOUNT, NULL);
2518 else
2519 return path_has_perm(cred, path, FILE__MOUNTON);
2520}
2521
2522static int selinux_umount(struct vfsmount *mnt, int flags)
2523{
2524 const struct cred *cred = current_cred();
2525
2526 return superblock_has_perm(cred, mnt->mnt_sb,
2527 FILESYSTEM__UNMOUNT, NULL);
2528}
2529
2530/* inode security operations */
2531
2532static int selinux_inode_alloc_security(struct inode *inode)
2533{
2534 return inode_alloc_security(inode);
2535}
2536
2537static void selinux_inode_free_security(struct inode *inode)
2538{
2539 inode_free_security(inode);
2540}
2541
2542static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543 const struct qstr *qstr, char **name,
2544 void **value, size_t *len)
2545{
2546 const struct task_security_struct *tsec = current_security();
2547 struct inode_security_struct *dsec;
2548 struct superblock_security_struct *sbsec;
2549 u32 sid, newsid, clen;
2550 int rc;
2551 char *namep = NULL, *context;
2552
2553 dsec = dir->i_security;
2554 sbsec = dir->i_sb->s_security;
2555
2556 sid = tsec->sid;
2557 newsid = tsec->create_sid;
2558
2559 if ((sbsec->flags & SE_SBINITIALIZED) &&
2560 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2561 newsid = sbsec->mntpoint_sid;
2562 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563 rc = security_transition_sid(sid, dsec->sid,
2564 inode_mode_to_security_class(inode->i_mode),
2565 qstr, &newsid);
2566 if (rc) {
2567 printk(KERN_WARNING "%s: "
2568 "security_transition_sid failed, rc=%d (dev=%s "
2569 "ino=%ld)\n",
2570 __func__,
2571 -rc, inode->i_sb->s_id, inode->i_ino);
2572 return rc;
2573 }
2574 }
2575
2576 /* Possibly defer initialization to selinux_complete_init. */
2577 if (sbsec->flags & SE_SBINITIALIZED) {
2578 struct inode_security_struct *isec = inode->i_security;
2579 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2580 isec->sid = newsid;
2581 isec->initialized = 1;
2582 }
2583
2584 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585 return -EOPNOTSUPP;
2586
2587 if (name) {
2588 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589 if (!namep)
2590 return -ENOMEM;
2591 *name = namep;
2592 }
2593
2594 if (value && len) {
2595 rc = security_sid_to_context_force(newsid, &context, &clen);
2596 if (rc) {
2597 kfree(namep);
2598 return rc;
2599 }
2600 *value = context;
2601 *len = clen;
2602 }
2603
2604 return 0;
2605}
2606
2607static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2608{
2609 return may_create(dir, dentry, SECCLASS_FILE);
2610}
2611
2612static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2613{
2614 return may_link(dir, old_dentry, MAY_LINK);
2615}
2616
2617static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2618{
2619 return may_link(dir, dentry, MAY_UNLINK);
2620}
2621
2622static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2623{
2624 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2625}
2626
2627static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2628{
2629 return may_create(dir, dentry, SECCLASS_DIR);
2630}
2631
2632static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2633{
2634 return may_link(dir, dentry, MAY_RMDIR);
2635}
2636
2637static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2638{
2639 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2640}
2641
2642static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643 struct inode *new_inode, struct dentry *new_dentry)
2644{
2645 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2646}
2647
2648static int selinux_inode_readlink(struct dentry *dentry)
2649{
2650 const struct cred *cred = current_cred();
2651
2652 return dentry_has_perm(cred, dentry, FILE__READ);
2653}
2654
2655static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2656{
2657 const struct cred *cred = current_cred();
2658
2659 return dentry_has_perm(cred, dentry, FILE__READ);
2660}
2661
2662static int selinux_inode_permission(struct inode *inode, int mask)
2663{
2664 const struct cred *cred = current_cred();
2665 struct common_audit_data ad;
2666 u32 perms;
2667 bool from_access;
2668 unsigned flags = mask & MAY_NOT_BLOCK;
2669
2670 from_access = mask & MAY_ACCESS;
2671 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2672
2673 /* No permission to check. Existence test. */
2674 if (!mask)
2675 return 0;
2676
2677 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2678 ad.u.inode = inode;
2679
2680 if (from_access)
2681 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2682
2683 perms = file_mask_to_av(inode->i_mode, mask);
2684
2685 return inode_has_perm(cred, inode, perms, &ad, flags);
2686}
2687
2688static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2689{
2690 const struct cred *cred = current_cred();
2691 unsigned int ia_valid = iattr->ia_valid;
2692
2693 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2694 if (ia_valid & ATTR_FORCE) {
2695 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2696 ATTR_FORCE);
2697 if (!ia_valid)
2698 return 0;
2699 }
2700
2701 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2702 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2703 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2704
2705 return dentry_has_perm(cred, dentry, FILE__WRITE);
2706}
2707
2708static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2709{
2710 const struct cred *cred = current_cred();
2711 struct path path;
2712
2713 path.dentry = dentry;
2714 path.mnt = mnt;
2715
2716 return path_has_perm(cred, &path, FILE__GETATTR);
2717}
2718
2719static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2720{
2721 const struct cred *cred = current_cred();
2722
2723 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2724 sizeof XATTR_SECURITY_PREFIX - 1)) {
2725 if (!strcmp(name, XATTR_NAME_CAPS)) {
2726 if (!capable(CAP_SETFCAP))
2727 return -EPERM;
2728 } else if (!capable(CAP_SYS_ADMIN)) {
2729 /* A different attribute in the security namespace.
2730 Restrict to administrator. */
2731 return -EPERM;
2732 }
2733 }
2734
2735 /* Not an attribute we recognize, so just check the
2736 ordinary setattr permission. */
2737 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2738}
2739
2740static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2741 const void *value, size_t size, int flags)
2742{
2743 struct inode *inode = dentry->d_inode;
2744 struct inode_security_struct *isec = inode->i_security;
2745 struct superblock_security_struct *sbsec;
2746 struct common_audit_data ad;
2747 u32 newsid, sid = current_sid();
2748 int rc = 0;
2749
2750 if (strcmp(name, XATTR_NAME_SELINUX))
2751 return selinux_inode_setotherxattr(dentry, name);
2752
2753 sbsec = inode->i_sb->s_security;
2754 if (!(sbsec->flags & SE_SBLABELSUPP))
2755 return -EOPNOTSUPP;
2756
2757 if (!inode_owner_or_capable(inode))
2758 return -EPERM;
2759
2760 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2761 ad.u.dentry = dentry;
2762
2763 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2764 FILE__RELABELFROM, &ad);
2765 if (rc)
2766 return rc;
2767
2768 rc = security_context_to_sid(value, size, &newsid);
2769 if (rc == -EINVAL) {
2770 if (!capable(CAP_MAC_ADMIN))
2771 return rc;
2772 rc = security_context_to_sid_force(value, size, &newsid);
2773 }
2774 if (rc)
2775 return rc;
2776
2777 rc = avc_has_perm(sid, newsid, isec->sclass,
2778 FILE__RELABELTO, &ad);
2779 if (rc)
2780 return rc;
2781
2782 rc = security_validate_transition(isec->sid, newsid, sid,
2783 isec->sclass);
2784 if (rc)
2785 return rc;
2786
2787 return avc_has_perm(newsid,
2788 sbsec->sid,
2789 SECCLASS_FILESYSTEM,
2790 FILESYSTEM__ASSOCIATE,
2791 &ad);
2792}
2793
2794static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2795 const void *value, size_t size,
2796 int flags)
2797{
2798 struct inode *inode = dentry->d_inode;
2799 struct inode_security_struct *isec = inode->i_security;
2800 u32 newsid;
2801 int rc;
2802
2803 if (strcmp(name, XATTR_NAME_SELINUX)) {
2804 /* Not an attribute we recognize, so nothing to do. */
2805 return;
2806 }
2807
2808 rc = security_context_to_sid_force(value, size, &newsid);
2809 if (rc) {
2810 printk(KERN_ERR "SELinux: unable to map context to SID"
2811 "for (%s, %lu), rc=%d\n",
2812 inode->i_sb->s_id, inode->i_ino, -rc);
2813 return;
2814 }
2815
2816 isec->sid = newsid;
2817 return;
2818}
2819
2820static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2821{
2822 const struct cred *cred = current_cred();
2823
2824 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2825}
2826
2827static int selinux_inode_listxattr(struct dentry *dentry)
2828{
2829 const struct cred *cred = current_cred();
2830
2831 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2832}
2833
2834static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2835{
2836 if (strcmp(name, XATTR_NAME_SELINUX))
2837 return selinux_inode_setotherxattr(dentry, name);
2838
2839 /* No one is allowed to remove a SELinux security label.
2840 You can change the label, but all data must be labeled. */
2841 return -EACCES;
2842}
2843
2844/*
2845 * Copy the inode security context value to the user.
2846 *
2847 * Permission check is handled by selinux_inode_getxattr hook.
2848 */
2849static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2850{
2851 u32 size;
2852 int error;
2853 char *context = NULL;
2854 struct inode_security_struct *isec = inode->i_security;
2855
2856 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2857 return -EOPNOTSUPP;
2858
2859 /*
2860 * If the caller has CAP_MAC_ADMIN, then get the raw context
2861 * value even if it is not defined by current policy; otherwise,
2862 * use the in-core value under current policy.
2863 * Use the non-auditing forms of the permission checks since
2864 * getxattr may be called by unprivileged processes commonly
2865 * and lack of permission just means that we fall back to the
2866 * in-core context value, not a denial.
2867 */
2868 error = selinux_capable(current, current_cred(),
2869 &init_user_ns, CAP_MAC_ADMIN,
2870 SECURITY_CAP_NOAUDIT);
2871 if (!error)
2872 error = security_sid_to_context_force(isec->sid, &context,
2873 &size);
2874 else
2875 error = security_sid_to_context(isec->sid, &context, &size);
2876 if (error)
2877 return error;
2878 error = size;
2879 if (alloc) {
2880 *buffer = context;
2881 goto out_nofree;
2882 }
2883 kfree(context);
2884out_nofree:
2885 return error;
2886}
2887
2888static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2889 const void *value, size_t size, int flags)
2890{
2891 struct inode_security_struct *isec = inode->i_security;
2892 u32 newsid;
2893 int rc;
2894
2895 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2896 return -EOPNOTSUPP;
2897
2898 if (!value || !size)
2899 return -EACCES;
2900
2901 rc = security_context_to_sid((void *)value, size, &newsid);
2902 if (rc)
2903 return rc;
2904
2905 isec->sid = newsid;
2906 isec->initialized = 1;
2907 return 0;
2908}
2909
2910static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2911{
2912 const int len = sizeof(XATTR_NAME_SELINUX);
2913 if (buffer && len <= buffer_size)
2914 memcpy(buffer, XATTR_NAME_SELINUX, len);
2915 return len;
2916}
2917
2918static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2919{
2920 struct inode_security_struct *isec = inode->i_security;
2921 *secid = isec->sid;
2922}
2923
2924/* file security operations */
2925
2926static int selinux_revalidate_file_permission(struct file *file, int mask)
2927{
2928 const struct cred *cred = current_cred();
2929 struct inode *inode = file->f_path.dentry->d_inode;
2930
2931 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2932 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2933 mask |= MAY_APPEND;
2934
2935 return file_has_perm(cred, file,
2936 file_mask_to_av(inode->i_mode, mask));
2937}
2938
2939static int selinux_file_permission(struct file *file, int mask)
2940{
2941 struct inode *inode = file->f_path.dentry->d_inode;
2942 struct file_security_struct *fsec = file->f_security;
2943 struct inode_security_struct *isec = inode->i_security;
2944 u32 sid = current_sid();
2945
2946 if (!mask)
2947 /* No permission to check. Existence test. */
2948 return 0;
2949
2950 if (sid == fsec->sid && fsec->isid == isec->sid &&
2951 fsec->pseqno == avc_policy_seqno())
2952 /* No change since dentry_open check. */
2953 return 0;
2954
2955 return selinux_revalidate_file_permission(file, mask);
2956}
2957
2958static int selinux_file_alloc_security(struct file *file)
2959{
2960 return file_alloc_security(file);
2961}
2962
2963static void selinux_file_free_security(struct file *file)
2964{
2965 file_free_security(file);
2966}
2967
2968static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2969 unsigned long arg)
2970{
2971 const struct cred *cred = current_cred();
2972 int error = 0;
2973
2974 switch (cmd) {
2975 case FIONREAD:
2976 /* fall through */
2977 case FIBMAP:
2978 /* fall through */
2979 case FIGETBSZ:
2980 /* fall through */
2981 case EXT2_IOC_GETFLAGS:
2982 /* fall through */
2983 case EXT2_IOC_GETVERSION:
2984 error = file_has_perm(cred, file, FILE__GETATTR);
2985 break;
2986
2987 case EXT2_IOC_SETFLAGS:
2988 /* fall through */
2989 case EXT2_IOC_SETVERSION:
2990 error = file_has_perm(cred, file, FILE__SETATTR);
2991 break;
2992
2993 /* sys_ioctl() checks */
2994 case FIONBIO:
2995 /* fall through */
2996 case FIOASYNC:
2997 error = file_has_perm(cred, file, 0);
2998 break;
2999
3000 case KDSKBENT:
3001 case KDSKBSENT:
3002 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3003 SECURITY_CAP_AUDIT);
3004 break;
3005
3006 /* default case assumes that the command will go
3007 * to the file's ioctl() function.
3008 */
3009 default:
3010 error = file_has_perm(cred, file, FILE__IOCTL);
3011 }
3012 return error;
3013}
3014
3015static int default_noexec;
3016
3017static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3018{
3019 const struct cred *cred = current_cred();
3020 int rc = 0;
3021
3022 if (default_noexec &&
3023 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3024 /*
3025 * We are making executable an anonymous mapping or a
3026 * private file mapping that will also be writable.
3027 * This has an additional check.
3028 */
3029 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3030 if (rc)
3031 goto error;
3032 }
3033
3034 if (file) {
3035 /* read access is always possible with a mapping */
3036 u32 av = FILE__READ;
3037
3038 /* write access only matters if the mapping is shared */
3039 if (shared && (prot & PROT_WRITE))
3040 av |= FILE__WRITE;
3041
3042 if (prot & PROT_EXEC)
3043 av |= FILE__EXECUTE;
3044
3045 return file_has_perm(cred, file, av);
3046 }
3047
3048error:
3049 return rc;
3050}
3051
3052static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3053 unsigned long prot, unsigned long flags,
3054 unsigned long addr, unsigned long addr_only)
3055{
3056 int rc = 0;
3057 u32 sid = current_sid();
3058
3059 /*
3060 * notice that we are intentionally putting the SELinux check before
3061 * the secondary cap_file_mmap check. This is such a likely attempt
3062 * at bad behaviour/exploit that we always want to get the AVC, even
3063 * if DAC would have also denied the operation.
3064 */
3065 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3066 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3067 MEMPROTECT__MMAP_ZERO, NULL);
3068 if (rc)
3069 return rc;
3070 }
3071
3072 /* do DAC check on address space usage */
3073 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3074 if (rc || addr_only)
3075 return rc;
3076
3077 if (selinux_checkreqprot)
3078 prot = reqprot;
3079
3080 return file_map_prot_check(file, prot,
3081 (flags & MAP_TYPE) == MAP_SHARED);
3082}
3083
3084static int selinux_file_mprotect(struct vm_area_struct *vma,
3085 unsigned long reqprot,
3086 unsigned long prot)
3087{
3088 const struct cred *cred = current_cred();
3089
3090 if (selinux_checkreqprot)
3091 prot = reqprot;
3092
3093 if (default_noexec &&
3094 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3095 int rc = 0;
3096 if (vma->vm_start >= vma->vm_mm->start_brk &&
3097 vma->vm_end <= vma->vm_mm->brk) {
3098 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3099 } else if (!vma->vm_file &&
3100 vma->vm_start <= vma->vm_mm->start_stack &&
3101 vma->vm_end >= vma->vm_mm->start_stack) {
3102 rc = current_has_perm(current, PROCESS__EXECSTACK);
3103 } else if (vma->vm_file && vma->anon_vma) {
3104 /*
3105 * We are making executable a file mapping that has
3106 * had some COW done. Since pages might have been
3107 * written, check ability to execute the possibly
3108 * modified content. This typically should only
3109 * occur for text relocations.
3110 */
3111 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3112 }
3113 if (rc)
3114 return rc;
3115 }
3116
3117 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3118}
3119
3120static int selinux_file_lock(struct file *file, unsigned int cmd)
3121{
3122 const struct cred *cred = current_cred();
3123
3124 return file_has_perm(cred, file, FILE__LOCK);
3125}
3126
3127static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3128 unsigned long arg)
3129{
3130 const struct cred *cred = current_cred();
3131 int err = 0;
3132
3133 switch (cmd) {
3134 case F_SETFL:
3135 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3136 err = -EINVAL;
3137 break;
3138 }
3139
3140 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3141 err = file_has_perm(cred, file, FILE__WRITE);
3142 break;
3143 }
3144 /* fall through */
3145 case F_SETOWN:
3146 case F_SETSIG:
3147 case F_GETFL:
3148 case F_GETOWN:
3149 case F_GETSIG:
3150 /* Just check FD__USE permission */
3151 err = file_has_perm(cred, file, 0);
3152 break;
3153 case F_GETLK:
3154 case F_SETLK:
3155 case F_SETLKW:
3156#if BITS_PER_LONG == 32
3157 case F_GETLK64:
3158 case F_SETLK64:
3159 case F_SETLKW64:
3160#endif
3161 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3162 err = -EINVAL;
3163 break;
3164 }
3165 err = file_has_perm(cred, file, FILE__LOCK);
3166 break;
3167 }
3168
3169 return err;
3170}
3171
3172static int selinux_file_set_fowner(struct file *file)
3173{
3174 struct file_security_struct *fsec;
3175
3176 fsec = file->f_security;
3177 fsec->fown_sid = current_sid();
3178
3179 return 0;
3180}
3181
3182static int selinux_file_send_sigiotask(struct task_struct *tsk,
3183 struct fown_struct *fown, int signum)
3184{
3185 struct file *file;
3186 u32 sid = task_sid(tsk);
3187 u32 perm;
3188 struct file_security_struct *fsec;
3189
3190 /* struct fown_struct is never outside the context of a struct file */
3191 file = container_of(fown, struct file, f_owner);
3192
3193 fsec = file->f_security;
3194
3195 if (!signum)
3196 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3197 else
3198 perm = signal_to_av(signum);
3199
3200 return avc_has_perm(fsec->fown_sid, sid,
3201 SECCLASS_PROCESS, perm, NULL);
3202}
3203
3204static int selinux_file_receive(struct file *file)
3205{
3206 const struct cred *cred = current_cred();
3207
3208 return file_has_perm(cred, file, file_to_av(file));
3209}
3210
3211static int selinux_dentry_open(struct file *file, const struct cred *cred)
3212{
3213 struct file_security_struct *fsec;
3214 struct inode *inode;
3215 struct inode_security_struct *isec;
3216
3217 inode = file->f_path.dentry->d_inode;
3218 fsec = file->f_security;
3219 isec = inode->i_security;
3220 /*
3221 * Save inode label and policy sequence number
3222 * at open-time so that selinux_file_permission
3223 * can determine whether revalidation is necessary.
3224 * Task label is already saved in the file security
3225 * struct as its SID.
3226 */
3227 fsec->isid = isec->sid;
3228 fsec->pseqno = avc_policy_seqno();
3229 /*
3230 * Since the inode label or policy seqno may have changed
3231 * between the selinux_inode_permission check and the saving
3232 * of state above, recheck that access is still permitted.
3233 * Otherwise, access might never be revalidated against the
3234 * new inode label or new policy.
3235 * This check is not redundant - do not remove.
3236 */
3237 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3238}
3239
3240/* task security operations */
3241
3242static int selinux_task_create(unsigned long clone_flags)
3243{
3244 return current_has_perm(current, PROCESS__FORK);
3245}
3246
3247/*
3248 * allocate the SELinux part of blank credentials
3249 */
3250static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3251{
3252 struct task_security_struct *tsec;
3253
3254 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3255 if (!tsec)
3256 return -ENOMEM;
3257
3258 cred->security = tsec;
3259 return 0;
3260}
3261
3262/*
3263 * detach and free the LSM part of a set of credentials
3264 */
3265static void selinux_cred_free(struct cred *cred)
3266{
3267 struct task_security_struct *tsec = cred->security;
3268
3269 /*
3270 * cred->security == NULL if security_cred_alloc_blank() or
3271 * security_prepare_creds() returned an error.
3272 */
3273 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3274 cred->security = (void *) 0x7UL;
3275 kfree(tsec);
3276}
3277
3278/*
3279 * prepare a new set of credentials for modification
3280 */
3281static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3282 gfp_t gfp)
3283{
3284 const struct task_security_struct *old_tsec;
3285 struct task_security_struct *tsec;
3286
3287 old_tsec = old->security;
3288
3289 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3290 if (!tsec)
3291 return -ENOMEM;
3292
3293 new->security = tsec;
3294 return 0;
3295}
3296
3297/*
3298 * transfer the SELinux data to a blank set of creds
3299 */
3300static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3301{
3302 const struct task_security_struct *old_tsec = old->security;
3303 struct task_security_struct *tsec = new->security;
3304
3305 *tsec = *old_tsec;
3306}
3307
3308/*
3309 * set the security data for a kernel service
3310 * - all the creation contexts are set to unlabelled
3311 */
3312static int selinux_kernel_act_as(struct cred *new, u32 secid)
3313{
3314 struct task_security_struct *tsec = new->security;
3315 u32 sid = current_sid();
3316 int ret;
3317
3318 ret = avc_has_perm(sid, secid,
3319 SECCLASS_KERNEL_SERVICE,
3320 KERNEL_SERVICE__USE_AS_OVERRIDE,
3321 NULL);
3322 if (ret == 0) {
3323 tsec->sid = secid;
3324 tsec->create_sid = 0;
3325 tsec->keycreate_sid = 0;
3326 tsec->sockcreate_sid = 0;
3327 }
3328 return ret;
3329}
3330
3331/*
3332 * set the file creation context in a security record to the same as the
3333 * objective context of the specified inode
3334 */
3335static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3336{
3337 struct inode_security_struct *isec = inode->i_security;
3338 struct task_security_struct *tsec = new->security;
3339 u32 sid = current_sid();
3340 int ret;
3341
3342 ret = avc_has_perm(sid, isec->sid,
3343 SECCLASS_KERNEL_SERVICE,
3344 KERNEL_SERVICE__CREATE_FILES_AS,
3345 NULL);
3346
3347 if (ret == 0)
3348 tsec->create_sid = isec->sid;
3349 return ret;
3350}
3351
3352static int selinux_kernel_module_request(char *kmod_name)
3353{
3354 u32 sid;
3355 struct common_audit_data ad;
3356
3357 sid = task_sid(current);
3358
3359 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3360 ad.u.kmod_name = kmod_name;
3361
3362 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3363 SYSTEM__MODULE_REQUEST, &ad);
3364}
3365
3366static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3367{
3368 return current_has_perm(p, PROCESS__SETPGID);
3369}
3370
3371static int selinux_task_getpgid(struct task_struct *p)
3372{
3373 return current_has_perm(p, PROCESS__GETPGID);
3374}
3375
3376static int selinux_task_getsid(struct task_struct *p)
3377{
3378 return current_has_perm(p, PROCESS__GETSESSION);
3379}
3380
3381static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3382{
3383 *secid = task_sid(p);
3384}
3385
3386static int selinux_task_setnice(struct task_struct *p, int nice)
3387{
3388 int rc;
3389
3390 rc = cap_task_setnice(p, nice);
3391 if (rc)
3392 return rc;
3393
3394 return current_has_perm(p, PROCESS__SETSCHED);
3395}
3396
3397static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3398{
3399 int rc;
3400
3401 rc = cap_task_setioprio(p, ioprio);
3402 if (rc)
3403 return rc;
3404
3405 return current_has_perm(p, PROCESS__SETSCHED);
3406}
3407
3408static int selinux_task_getioprio(struct task_struct *p)
3409{
3410 return current_has_perm(p, PROCESS__GETSCHED);
3411}
3412
3413static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3414 struct rlimit *new_rlim)
3415{
3416 struct rlimit *old_rlim = p->signal->rlim + resource;
3417
3418 /* Control the ability to change the hard limit (whether
3419 lowering or raising it), so that the hard limit can
3420 later be used as a safe reset point for the soft limit
3421 upon context transitions. See selinux_bprm_committing_creds. */
3422 if (old_rlim->rlim_max != new_rlim->rlim_max)
3423 return current_has_perm(p, PROCESS__SETRLIMIT);
3424
3425 return 0;
3426}
3427
3428static int selinux_task_setscheduler(struct task_struct *p)
3429{
3430 int rc;
3431
3432 rc = cap_task_setscheduler(p);
3433 if (rc)
3434 return rc;
3435
3436 return current_has_perm(p, PROCESS__SETSCHED);
3437}
3438
3439static int selinux_task_getscheduler(struct task_struct *p)
3440{
3441 return current_has_perm(p, PROCESS__GETSCHED);
3442}
3443
3444static int selinux_task_movememory(struct task_struct *p)
3445{
3446 return current_has_perm(p, PROCESS__SETSCHED);
3447}
3448
3449static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3450 int sig, u32 secid)
3451{
3452 u32 perm;
3453 int rc;
3454
3455 if (!sig)
3456 perm = PROCESS__SIGNULL; /* null signal; existence test */
3457 else
3458 perm = signal_to_av(sig);
3459 if (secid)
3460 rc = avc_has_perm(secid, task_sid(p),
3461 SECCLASS_PROCESS, perm, NULL);
3462 else
3463 rc = current_has_perm(p, perm);
3464 return rc;
3465}
3466
3467static int selinux_task_wait(struct task_struct *p)
3468{
3469 return task_has_perm(p, current, PROCESS__SIGCHLD);
3470}
3471
3472static void selinux_task_to_inode(struct task_struct *p,
3473 struct inode *inode)
3474{
3475 struct inode_security_struct *isec = inode->i_security;
3476 u32 sid = task_sid(p);
3477
3478 isec->sid = sid;
3479 isec->initialized = 1;
3480}
3481
3482/* Returns error only if unable to parse addresses */
3483static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3484 struct common_audit_data *ad, u8 *proto)
3485{
3486 int offset, ihlen, ret = -EINVAL;
3487 struct iphdr _iph, *ih;
3488
3489 offset = skb_network_offset(skb);
3490 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3491 if (ih == NULL)
3492 goto out;
3493
3494 ihlen = ih->ihl * 4;
3495 if (ihlen < sizeof(_iph))
3496 goto out;
3497
3498 ad->u.net.v4info.saddr = ih->saddr;
3499 ad->u.net.v4info.daddr = ih->daddr;
3500 ret = 0;
3501
3502 if (proto)
3503 *proto = ih->protocol;
3504
3505 switch (ih->protocol) {
3506 case IPPROTO_TCP: {
3507 struct tcphdr _tcph, *th;
3508
3509 if (ntohs(ih->frag_off) & IP_OFFSET)
3510 break;
3511
3512 offset += ihlen;
3513 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3514 if (th == NULL)
3515 break;
3516
3517 ad->u.net.sport = th->source;
3518 ad->u.net.dport = th->dest;
3519 break;
3520 }
3521
3522 case IPPROTO_UDP: {
3523 struct udphdr _udph, *uh;
3524
3525 if (ntohs(ih->frag_off) & IP_OFFSET)
3526 break;
3527
3528 offset += ihlen;
3529 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3530 if (uh == NULL)
3531 break;
3532
3533 ad->u.net.sport = uh->source;
3534 ad->u.net.dport = uh->dest;
3535 break;
3536 }
3537
3538 case IPPROTO_DCCP: {
3539 struct dccp_hdr _dccph, *dh;
3540
3541 if (ntohs(ih->frag_off) & IP_OFFSET)
3542 break;
3543
3544 offset += ihlen;
3545 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3546 if (dh == NULL)
3547 break;
3548
3549 ad->u.net.sport = dh->dccph_sport;
3550 ad->u.net.dport = dh->dccph_dport;
3551 break;
3552 }
3553
3554 default:
3555 break;
3556 }
3557out:
3558 return ret;
3559}
3560
3561#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3562
3563/* Returns error only if unable to parse addresses */
3564static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3565 struct common_audit_data *ad, u8 *proto)
3566{
3567 u8 nexthdr;
3568 int ret = -EINVAL, offset;
3569 struct ipv6hdr _ipv6h, *ip6;
3570
3571 offset = skb_network_offset(skb);
3572 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3573 if (ip6 == NULL)
3574 goto out;
3575
3576 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3577 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3578 ret = 0;
3579
3580 nexthdr = ip6->nexthdr;
3581 offset += sizeof(_ipv6h);
3582 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3583 if (offset < 0)
3584 goto out;
3585
3586 if (proto)
3587 *proto = nexthdr;
3588
3589 switch (nexthdr) {
3590 case IPPROTO_TCP: {
3591 struct tcphdr _tcph, *th;
3592
3593 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3594 if (th == NULL)
3595 break;
3596
3597 ad->u.net.sport = th->source;
3598 ad->u.net.dport = th->dest;
3599 break;
3600 }
3601
3602 case IPPROTO_UDP: {
3603 struct udphdr _udph, *uh;
3604
3605 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3606 if (uh == NULL)
3607 break;
3608
3609 ad->u.net.sport = uh->source;
3610 ad->u.net.dport = uh->dest;
3611 break;
3612 }
3613
3614 case IPPROTO_DCCP: {
3615 struct dccp_hdr _dccph, *dh;
3616
3617 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3618 if (dh == NULL)
3619 break;
3620
3621 ad->u.net.sport = dh->dccph_sport;
3622 ad->u.net.dport = dh->dccph_dport;
3623 break;
3624 }
3625
3626 /* includes fragments */
3627 default:
3628 break;
3629 }
3630out:
3631 return ret;
3632}
3633
3634#endif /* IPV6 */
3635
3636static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3637 char **_addrp, int src, u8 *proto)
3638{
3639 char *addrp;
3640 int ret;
3641
3642 switch (ad->u.net.family) {
3643 case PF_INET:
3644 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3645 if (ret)
3646 goto parse_error;
3647 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3648 &ad->u.net.v4info.daddr);
3649 goto okay;
3650
3651#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3652 case PF_INET6:
3653 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3654 if (ret)
3655 goto parse_error;
3656 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3657 &ad->u.net.v6info.daddr);
3658 goto okay;
3659#endif /* IPV6 */
3660 default:
3661 addrp = NULL;
3662 goto okay;
3663 }
3664
3665parse_error:
3666 printk(KERN_WARNING
3667 "SELinux: failure in selinux_parse_skb(),"
3668 " unable to parse packet\n");
3669 return ret;
3670
3671okay:
3672 if (_addrp)
3673 *_addrp = addrp;
3674 return 0;
3675}
3676
3677/**
3678 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3679 * @skb: the packet
3680 * @family: protocol family
3681 * @sid: the packet's peer label SID
3682 *
3683 * Description:
3684 * Check the various different forms of network peer labeling and determine
3685 * the peer label/SID for the packet; most of the magic actually occurs in
3686 * the security server function security_net_peersid_cmp(). The function
3687 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3688 * or -EACCES if @sid is invalid due to inconsistencies with the different
3689 * peer labels.
3690 *
3691 */
3692static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3693{
3694 int err;
3695 u32 xfrm_sid;
3696 u32 nlbl_sid;
3697 u32 nlbl_type;
3698
3699 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3700 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3701
3702 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3703 if (unlikely(err)) {
3704 printk(KERN_WARNING
3705 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3706 " unable to determine packet's peer label\n");
3707 return -EACCES;
3708 }
3709
3710 return 0;
3711}
3712
3713/* socket security operations */
3714
3715static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3716 u16 secclass, u32 *socksid)
3717{
3718 if (tsec->sockcreate_sid > SECSID_NULL) {
3719 *socksid = tsec->sockcreate_sid;
3720 return 0;
3721 }
3722
3723 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3724 socksid);
3725}
3726
3727static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3728{
3729 struct sk_security_struct *sksec = sk->sk_security;
3730 struct common_audit_data ad;
3731 u32 tsid = task_sid(task);
3732
3733 if (sksec->sid == SECINITSID_KERNEL)
3734 return 0;
3735
3736 COMMON_AUDIT_DATA_INIT(&ad, NET);
3737 ad.u.net.sk = sk;
3738
3739 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3740}
3741
3742static int selinux_socket_create(int family, int type,
3743 int protocol, int kern)
3744{
3745 const struct task_security_struct *tsec = current_security();
3746 u32 newsid;
3747 u16 secclass;
3748 int rc;
3749
3750 if (kern)
3751 return 0;
3752
3753 secclass = socket_type_to_security_class(family, type, protocol);
3754 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3755 if (rc)
3756 return rc;
3757
3758 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3759}
3760
3761static int selinux_socket_post_create(struct socket *sock, int family,
3762 int type, int protocol, int kern)
3763{
3764 const struct task_security_struct *tsec = current_security();
3765 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3766 struct sk_security_struct *sksec;
3767 int err = 0;
3768
3769 isec->sclass = socket_type_to_security_class(family, type, protocol);
3770
3771 if (kern)
3772 isec->sid = SECINITSID_KERNEL;
3773 else {
3774 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3775 if (err)
3776 return err;
3777 }
3778
3779 isec->initialized = 1;
3780
3781 if (sock->sk) {
3782 sksec = sock->sk->sk_security;
3783 sksec->sid = isec->sid;
3784 sksec->sclass = isec->sclass;
3785 err = selinux_netlbl_socket_post_create(sock->sk, family);
3786 }
3787
3788 return err;
3789}
3790
3791/* Range of port numbers used to automatically bind.
3792 Need to determine whether we should perform a name_bind
3793 permission check between the socket and the port number. */
3794
3795static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3796{
3797 struct sock *sk = sock->sk;
3798 u16 family;
3799 int err;
3800
3801 err = sock_has_perm(current, sk, SOCKET__BIND);
3802 if (err)
3803 goto out;
3804
3805 /*
3806 * If PF_INET or PF_INET6, check name_bind permission for the port.
3807 * Multiple address binding for SCTP is not supported yet: we just
3808 * check the first address now.
3809 */
3810 family = sk->sk_family;
3811 if (family == PF_INET || family == PF_INET6) {
3812 char *addrp;
3813 struct sk_security_struct *sksec = sk->sk_security;
3814 struct common_audit_data ad;
3815 struct sockaddr_in *addr4 = NULL;
3816 struct sockaddr_in6 *addr6 = NULL;
3817 unsigned short snum;
3818 u32 sid, node_perm;
3819
3820 if (family == PF_INET) {
3821 addr4 = (struct sockaddr_in *)address;
3822 snum = ntohs(addr4->sin_port);
3823 addrp = (char *)&addr4->sin_addr.s_addr;
3824 } else {
3825 addr6 = (struct sockaddr_in6 *)address;
3826 snum = ntohs(addr6->sin6_port);
3827 addrp = (char *)&addr6->sin6_addr.s6_addr;
3828 }
3829
3830 if (snum) {
3831 int low, high;
3832
3833 inet_get_local_port_range(&low, &high);
3834
3835 if (snum < max(PROT_SOCK, low) || snum > high) {
3836 err = sel_netport_sid(sk->sk_protocol,
3837 snum, &sid);
3838 if (err)
3839 goto out;
3840 COMMON_AUDIT_DATA_INIT(&ad, NET);
3841 ad.u.net.sport = htons(snum);
3842 ad.u.net.family = family;
3843 err = avc_has_perm(sksec->sid, sid,
3844 sksec->sclass,
3845 SOCKET__NAME_BIND, &ad);
3846 if (err)
3847 goto out;
3848 }
3849 }
3850
3851 switch (sksec->sclass) {
3852 case SECCLASS_TCP_SOCKET:
3853 node_perm = TCP_SOCKET__NODE_BIND;
3854 break;
3855
3856 case SECCLASS_UDP_SOCKET:
3857 node_perm = UDP_SOCKET__NODE_BIND;
3858 break;
3859
3860 case SECCLASS_DCCP_SOCKET:
3861 node_perm = DCCP_SOCKET__NODE_BIND;
3862 break;
3863
3864 default:
3865 node_perm = RAWIP_SOCKET__NODE_BIND;
3866 break;
3867 }
3868
3869 err = sel_netnode_sid(addrp, family, &sid);
3870 if (err)
3871 goto out;
3872
3873 COMMON_AUDIT_DATA_INIT(&ad, NET);
3874 ad.u.net.sport = htons(snum);
3875 ad.u.net.family = family;
3876
3877 if (family == PF_INET)
3878 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3879 else
3880 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3881
3882 err = avc_has_perm(sksec->sid, sid,
3883 sksec->sclass, node_perm, &ad);
3884 if (err)
3885 goto out;
3886 }
3887out:
3888 return err;
3889}
3890
3891static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3892{
3893 struct sock *sk = sock->sk;
3894 struct sk_security_struct *sksec = sk->sk_security;
3895 int err;
3896
3897 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3898 if (err)
3899 return err;
3900
3901 /*
3902 * If a TCP or DCCP socket, check name_connect permission for the port.
3903 */
3904 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3905 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3906 struct common_audit_data ad;
3907 struct sockaddr_in *addr4 = NULL;
3908 struct sockaddr_in6 *addr6 = NULL;
3909 unsigned short snum;
3910 u32 sid, perm;
3911
3912 if (sk->sk_family == PF_INET) {
3913 addr4 = (struct sockaddr_in *)address;
3914 if (addrlen < sizeof(struct sockaddr_in))
3915 return -EINVAL;
3916 snum = ntohs(addr4->sin_port);
3917 } else {
3918 addr6 = (struct sockaddr_in6 *)address;
3919 if (addrlen < SIN6_LEN_RFC2133)
3920 return -EINVAL;
3921 snum = ntohs(addr6->sin6_port);
3922 }
3923
3924 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3925 if (err)
3926 goto out;
3927
3928 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3929 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3930
3931 COMMON_AUDIT_DATA_INIT(&ad, NET);
3932 ad.u.net.dport = htons(snum);
3933 ad.u.net.family = sk->sk_family;
3934 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3935 if (err)
3936 goto out;
3937 }
3938
3939 err = selinux_netlbl_socket_connect(sk, address);
3940
3941out:
3942 return err;
3943}
3944
3945static int selinux_socket_listen(struct socket *sock, int backlog)
3946{
3947 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3948}
3949
3950static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3951{
3952 int err;
3953 struct inode_security_struct *isec;
3954 struct inode_security_struct *newisec;
3955
3956 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3957 if (err)
3958 return err;
3959
3960 newisec = SOCK_INODE(newsock)->i_security;
3961
3962 isec = SOCK_INODE(sock)->i_security;
3963 newisec->sclass = isec->sclass;
3964 newisec->sid = isec->sid;
3965 newisec->initialized = 1;
3966
3967 return 0;
3968}
3969
3970static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3971 int size)
3972{
3973 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3974}
3975
3976static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3977 int size, int flags)
3978{
3979 return sock_has_perm(current, sock->sk, SOCKET__READ);
3980}
3981
3982static int selinux_socket_getsockname(struct socket *sock)
3983{
3984 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3985}
3986
3987static int selinux_socket_getpeername(struct socket *sock)
3988{
3989 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3990}
3991
3992static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3993{
3994 int err;
3995
3996 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3997 if (err)
3998 return err;
3999
4000 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4001}
4002
4003static int selinux_socket_getsockopt(struct socket *sock, int level,
4004 int optname)
4005{
4006 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4007}
4008
4009static int selinux_socket_shutdown(struct socket *sock, int how)
4010{
4011 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4012}
4013
4014static int selinux_socket_unix_stream_connect(struct sock *sock,
4015 struct sock *other,
4016 struct sock *newsk)
4017{
4018 struct sk_security_struct *sksec_sock = sock->sk_security;
4019 struct sk_security_struct *sksec_other = other->sk_security;
4020 struct sk_security_struct *sksec_new = newsk->sk_security;
4021 struct common_audit_data ad;
4022 int err;
4023
4024 COMMON_AUDIT_DATA_INIT(&ad, NET);
4025 ad.u.net.sk = other;
4026
4027 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4028 sksec_other->sclass,
4029 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4030 if (err)
4031 return err;
4032
4033 /* server child socket */
4034 sksec_new->peer_sid = sksec_sock->sid;
4035 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4036 &sksec_new->sid);
4037 if (err)
4038 return err;
4039
4040 /* connecting socket */
4041 sksec_sock->peer_sid = sksec_new->sid;
4042
4043 return 0;
4044}
4045
4046static int selinux_socket_unix_may_send(struct socket *sock,
4047 struct socket *other)
4048{
4049 struct sk_security_struct *ssec = sock->sk->sk_security;
4050 struct sk_security_struct *osec = other->sk->sk_security;
4051 struct common_audit_data ad;
4052
4053 COMMON_AUDIT_DATA_INIT(&ad, NET);
4054 ad.u.net.sk = other->sk;
4055
4056 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4057 &ad);
4058}
4059
4060static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4061 u32 peer_sid,
4062 struct common_audit_data *ad)
4063{
4064 int err;
4065 u32 if_sid;
4066 u32 node_sid;
4067
4068 err = sel_netif_sid(ifindex, &if_sid);
4069 if (err)
4070 return err;
4071 err = avc_has_perm(peer_sid, if_sid,
4072 SECCLASS_NETIF, NETIF__INGRESS, ad);
4073 if (err)
4074 return err;
4075
4076 err = sel_netnode_sid(addrp, family, &node_sid);
4077 if (err)
4078 return err;
4079 return avc_has_perm(peer_sid, node_sid,
4080 SECCLASS_NODE, NODE__RECVFROM, ad);
4081}
4082
4083static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4084 u16 family)
4085{
4086 int err = 0;
4087 struct sk_security_struct *sksec = sk->sk_security;
4088 u32 sk_sid = sksec->sid;
4089 struct common_audit_data ad;
4090 char *addrp;
4091
4092 COMMON_AUDIT_DATA_INIT(&ad, NET);
4093 ad.u.net.netif = skb->skb_iif;
4094 ad.u.net.family = family;
4095 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4096 if (err)
4097 return err;
4098
4099 if (selinux_secmark_enabled()) {
4100 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4101 PACKET__RECV, &ad);
4102 if (err)
4103 return err;
4104 }
4105
4106 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4107 if (err)
4108 return err;
4109 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4110
4111 return err;
4112}
4113
4114static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4115{
4116 int err;
4117 struct sk_security_struct *sksec = sk->sk_security;
4118 u16 family = sk->sk_family;
4119 u32 sk_sid = sksec->sid;
4120 struct common_audit_data ad;
4121 char *addrp;
4122 u8 secmark_active;
4123 u8 peerlbl_active;
4124
4125 if (family != PF_INET && family != PF_INET6)
4126 return 0;
4127
4128 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4129 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4130 family = PF_INET;
4131
4132 /* If any sort of compatibility mode is enabled then handoff processing
4133 * to the selinux_sock_rcv_skb_compat() function to deal with the
4134 * special handling. We do this in an attempt to keep this function
4135 * as fast and as clean as possible. */
4136 if (!selinux_policycap_netpeer)
4137 return selinux_sock_rcv_skb_compat(sk, skb, family);
4138
4139 secmark_active = selinux_secmark_enabled();
4140 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4141 if (!secmark_active && !peerlbl_active)
4142 return 0;
4143
4144 COMMON_AUDIT_DATA_INIT(&ad, NET);
4145 ad.u.net.netif = skb->skb_iif;
4146 ad.u.net.family = family;
4147 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4148 if (err)
4149 return err;
4150
4151 if (peerlbl_active) {
4152 u32 peer_sid;
4153
4154 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4155 if (err)
4156 return err;
4157 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4158 peer_sid, &ad);
4159 if (err) {
4160 selinux_netlbl_err(skb, err, 0);
4161 return err;
4162 }
4163 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4164 PEER__RECV, &ad);
4165 if (err)
4166 selinux_netlbl_err(skb, err, 0);
4167 }
4168
4169 if (secmark_active) {
4170 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4171 PACKET__RECV, &ad);
4172 if (err)
4173 return err;
4174 }
4175
4176 return err;
4177}
4178
4179static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4180 int __user *optlen, unsigned len)
4181{
4182 int err = 0;
4183 char *scontext;
4184 u32 scontext_len;
4185 struct sk_security_struct *sksec = sock->sk->sk_security;
4186 u32 peer_sid = SECSID_NULL;
4187
4188 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4189 sksec->sclass == SECCLASS_TCP_SOCKET)
4190 peer_sid = sksec->peer_sid;
4191 if (peer_sid == SECSID_NULL)
4192 return -ENOPROTOOPT;
4193
4194 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4195 if (err)
4196 return err;
4197
4198 if (scontext_len > len) {
4199 err = -ERANGE;
4200 goto out_len;
4201 }
4202
4203 if (copy_to_user(optval, scontext, scontext_len))
4204 err = -EFAULT;
4205
4206out_len:
4207 if (put_user(scontext_len, optlen))
4208 err = -EFAULT;
4209 kfree(scontext);
4210 return err;
4211}
4212
4213static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4214{
4215 u32 peer_secid = SECSID_NULL;
4216 u16 family;
4217
4218 if (skb && skb->protocol == htons(ETH_P_IP))
4219 family = PF_INET;
4220 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4221 family = PF_INET6;
4222 else if (sock)
4223 family = sock->sk->sk_family;
4224 else
4225 goto out;
4226
4227 if (sock && family == PF_UNIX)
4228 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4229 else if (skb)
4230 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4231
4232out:
4233 *secid = peer_secid;
4234 if (peer_secid == SECSID_NULL)
4235 return -EINVAL;
4236 return 0;
4237}
4238
4239static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4240{
4241 struct sk_security_struct *sksec;
4242
4243 sksec = kzalloc(sizeof(*sksec), priority);
4244 if (!sksec)
4245 return -ENOMEM;
4246
4247 sksec->peer_sid = SECINITSID_UNLABELED;
4248 sksec->sid = SECINITSID_UNLABELED;
4249 selinux_netlbl_sk_security_reset(sksec);
4250 sk->sk_security = sksec;
4251
4252 return 0;
4253}
4254
4255static void selinux_sk_free_security(struct sock *sk)
4256{
4257 struct sk_security_struct *sksec = sk->sk_security;
4258
4259 sk->sk_security = NULL;
4260 selinux_netlbl_sk_security_free(sksec);
4261 kfree(sksec);
4262}
4263
4264static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4265{
4266 struct sk_security_struct *sksec = sk->sk_security;
4267 struct sk_security_struct *newsksec = newsk->sk_security;
4268
4269 newsksec->sid = sksec->sid;
4270 newsksec->peer_sid = sksec->peer_sid;
4271 newsksec->sclass = sksec->sclass;
4272
4273 selinux_netlbl_sk_security_reset(newsksec);
4274}
4275
4276static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4277{
4278 if (!sk)
4279 *secid = SECINITSID_ANY_SOCKET;
4280 else {
4281 struct sk_security_struct *sksec = sk->sk_security;
4282
4283 *secid = sksec->sid;
4284 }
4285}
4286
4287static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4288{
4289 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4290 struct sk_security_struct *sksec = sk->sk_security;
4291
4292 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4293 sk->sk_family == PF_UNIX)
4294 isec->sid = sksec->sid;
4295 sksec->sclass = isec->sclass;
4296}
4297
4298static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4299 struct request_sock *req)
4300{
4301 struct sk_security_struct *sksec = sk->sk_security;
4302 int err;
4303 u16 family = sk->sk_family;
4304 u32 newsid;
4305 u32 peersid;
4306
4307 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4308 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4309 family = PF_INET;
4310
4311 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4312 if (err)
4313 return err;
4314 if (peersid == SECSID_NULL) {
4315 req->secid = sksec->sid;
4316 req->peer_secid = SECSID_NULL;
4317 } else {
4318 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4319 if (err)
4320 return err;
4321 req->secid = newsid;
4322 req->peer_secid = peersid;
4323 }
4324
4325 return selinux_netlbl_inet_conn_request(req, family);
4326}
4327
4328static void selinux_inet_csk_clone(struct sock *newsk,
4329 const struct request_sock *req)
4330{
4331 struct sk_security_struct *newsksec = newsk->sk_security;
4332
4333 newsksec->sid = req->secid;
4334 newsksec->peer_sid = req->peer_secid;
4335 /* NOTE: Ideally, we should also get the isec->sid for the
4336 new socket in sync, but we don't have the isec available yet.
4337 So we will wait until sock_graft to do it, by which
4338 time it will have been created and available. */
4339
4340 /* We don't need to take any sort of lock here as we are the only
4341 * thread with access to newsksec */
4342 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4343}
4344
4345static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4346{
4347 u16 family = sk->sk_family;
4348 struct sk_security_struct *sksec = sk->sk_security;
4349
4350 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4351 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4352 family = PF_INET;
4353
4354 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4355}
4356
4357static int selinux_secmark_relabel_packet(u32 sid)
4358{
4359 const struct task_security_struct *__tsec;
4360 u32 tsid;
4361
4362 __tsec = current_security();
4363 tsid = __tsec->sid;
4364
4365 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4366}
4367
4368static void selinux_secmark_refcount_inc(void)
4369{
4370 atomic_inc(&selinux_secmark_refcount);
4371}
4372
4373static void selinux_secmark_refcount_dec(void)
4374{
4375 atomic_dec(&selinux_secmark_refcount);
4376}
4377
4378static void selinux_req_classify_flow(const struct request_sock *req,
4379 struct flowi *fl)
4380{
4381 fl->flowi_secid = req->secid;
4382}
4383
4384static int selinux_tun_dev_create(void)
4385{
4386 u32 sid = current_sid();
4387
4388 /* we aren't taking into account the "sockcreate" SID since the socket
4389 * that is being created here is not a socket in the traditional sense,
4390 * instead it is a private sock, accessible only to the kernel, and
4391 * representing a wide range of network traffic spanning multiple
4392 * connections unlike traditional sockets - check the TUN driver to
4393 * get a better understanding of why this socket is special */
4394
4395 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4396 NULL);
4397}
4398
4399static void selinux_tun_dev_post_create(struct sock *sk)
4400{
4401 struct sk_security_struct *sksec = sk->sk_security;
4402
4403 /* we don't currently perform any NetLabel based labeling here and it
4404 * isn't clear that we would want to do so anyway; while we could apply
4405 * labeling without the support of the TUN user the resulting labeled
4406 * traffic from the other end of the connection would almost certainly
4407 * cause confusion to the TUN user that had no idea network labeling
4408 * protocols were being used */
4409
4410 /* see the comments in selinux_tun_dev_create() about why we don't use
4411 * the sockcreate SID here */
4412
4413 sksec->sid = current_sid();
4414 sksec->sclass = SECCLASS_TUN_SOCKET;
4415}
4416
4417static int selinux_tun_dev_attach(struct sock *sk)
4418{
4419 struct sk_security_struct *sksec = sk->sk_security;
4420 u32 sid = current_sid();
4421 int err;
4422
4423 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4424 TUN_SOCKET__RELABELFROM, NULL);
4425 if (err)
4426 return err;
4427 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4428 TUN_SOCKET__RELABELTO, NULL);
4429 if (err)
4430 return err;
4431
4432 sksec->sid = sid;
4433
4434 return 0;
4435}
4436
4437static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4438{
4439 int err = 0;
4440 u32 perm;
4441 struct nlmsghdr *nlh;
4442 struct sk_security_struct *sksec = sk->sk_security;
4443
4444 if (skb->len < NLMSG_SPACE(0)) {
4445 err = -EINVAL;
4446 goto out;
4447 }
4448 nlh = nlmsg_hdr(skb);
4449
4450 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4451 if (err) {
4452 if (err == -EINVAL) {
4453 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4454 "SELinux: unrecognized netlink message"
4455 " type=%hu for sclass=%hu\n",
4456 nlh->nlmsg_type, sksec->sclass);
4457 if (!selinux_enforcing || security_get_allow_unknown())
4458 err = 0;
4459 }
4460
4461 /* Ignore */
4462 if (err == -ENOENT)
4463 err = 0;
4464 goto out;
4465 }
4466
4467 err = sock_has_perm(current, sk, perm);
4468out:
4469 return err;
4470}
4471
4472#ifdef CONFIG_NETFILTER
4473
4474static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4475 u16 family)
4476{
4477 int err;
4478 char *addrp;
4479 u32 peer_sid;
4480 struct common_audit_data ad;
4481 u8 secmark_active;
4482 u8 netlbl_active;
4483 u8 peerlbl_active;
4484
4485 if (!selinux_policycap_netpeer)
4486 return NF_ACCEPT;
4487
4488 secmark_active = selinux_secmark_enabled();
4489 netlbl_active = netlbl_enabled();
4490 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4491 if (!secmark_active && !peerlbl_active)
4492 return NF_ACCEPT;
4493
4494 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4495 return NF_DROP;
4496
4497 COMMON_AUDIT_DATA_INIT(&ad, NET);
4498 ad.u.net.netif = ifindex;
4499 ad.u.net.family = family;
4500 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4501 return NF_DROP;
4502
4503 if (peerlbl_active) {
4504 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4505 peer_sid, &ad);
4506 if (err) {
4507 selinux_netlbl_err(skb, err, 1);
4508 return NF_DROP;
4509 }
4510 }
4511
4512 if (secmark_active)
4513 if (avc_has_perm(peer_sid, skb->secmark,
4514 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4515 return NF_DROP;
4516
4517 if (netlbl_active)
4518 /* we do this in the FORWARD path and not the POST_ROUTING
4519 * path because we want to make sure we apply the necessary
4520 * labeling before IPsec is applied so we can leverage AH
4521 * protection */
4522 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4523 return NF_DROP;
4524
4525 return NF_ACCEPT;
4526}
4527
4528static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4529 struct sk_buff *skb,
4530 const struct net_device *in,
4531 const struct net_device *out,
4532 int (*okfn)(struct sk_buff *))
4533{
4534 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4535}
4536
4537#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4538static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4539 struct sk_buff *skb,
4540 const struct net_device *in,
4541 const struct net_device *out,
4542 int (*okfn)(struct sk_buff *))
4543{
4544 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4545}
4546#endif /* IPV6 */
4547
4548static unsigned int selinux_ip_output(struct sk_buff *skb,
4549 u16 family)
4550{
4551 u32 sid;
4552
4553 if (!netlbl_enabled())
4554 return NF_ACCEPT;
4555
4556 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4557 * because we want to make sure we apply the necessary labeling
4558 * before IPsec is applied so we can leverage AH protection */
4559 if (skb->sk) {
4560 struct sk_security_struct *sksec = skb->sk->sk_security;
4561 sid = sksec->sid;
4562 } else
4563 sid = SECINITSID_KERNEL;
4564 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4565 return NF_DROP;
4566
4567 return NF_ACCEPT;
4568}
4569
4570static unsigned int selinux_ipv4_output(unsigned int hooknum,
4571 struct sk_buff *skb,
4572 const struct net_device *in,
4573 const struct net_device *out,
4574 int (*okfn)(struct sk_buff *))
4575{
4576 return selinux_ip_output(skb, PF_INET);
4577}
4578
4579static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4580 int ifindex,
4581 u16 family)
4582{
4583 struct sock *sk = skb->sk;
4584 struct sk_security_struct *sksec;
4585 struct common_audit_data ad;
4586 char *addrp;
4587 u8 proto;
4588
4589 if (sk == NULL)
4590 return NF_ACCEPT;
4591 sksec = sk->sk_security;
4592
4593 COMMON_AUDIT_DATA_INIT(&ad, NET);
4594 ad.u.net.netif = ifindex;
4595 ad.u.net.family = family;
4596 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4597 return NF_DROP;
4598
4599 if (selinux_secmark_enabled())
4600 if (avc_has_perm(sksec->sid, skb->secmark,
4601 SECCLASS_PACKET, PACKET__SEND, &ad))
4602 return NF_DROP_ERR(-ECONNREFUSED);
4603
4604 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4605 return NF_DROP_ERR(-ECONNREFUSED);
4606
4607 return NF_ACCEPT;
4608}
4609
4610static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4611 u16 family)
4612{
4613 u32 secmark_perm;
4614 u32 peer_sid;
4615 struct sock *sk;
4616 struct common_audit_data ad;
4617 char *addrp;
4618 u8 secmark_active;
4619 u8 peerlbl_active;
4620
4621 /* If any sort of compatibility mode is enabled then handoff processing
4622 * to the selinux_ip_postroute_compat() function to deal with the
4623 * special handling. We do this in an attempt to keep this function
4624 * as fast and as clean as possible. */
4625 if (!selinux_policycap_netpeer)
4626 return selinux_ip_postroute_compat(skb, ifindex, family);
4627#ifdef CONFIG_XFRM
4628 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4629 * packet transformation so allow the packet to pass without any checks
4630 * since we'll have another chance to perform access control checks
4631 * when the packet is on it's final way out.
4632 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4633 * is NULL, in this case go ahead and apply access control. */
4634 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4635 return NF_ACCEPT;
4636#endif
4637 secmark_active = selinux_secmark_enabled();
4638 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4639 if (!secmark_active && !peerlbl_active)
4640 return NF_ACCEPT;
4641
4642 /* if the packet is being forwarded then get the peer label from the
4643 * packet itself; otherwise check to see if it is from a local
4644 * application or the kernel, if from an application get the peer label
4645 * from the sending socket, otherwise use the kernel's sid */
4646 sk = skb->sk;
4647 if (sk == NULL) {
4648 if (skb->skb_iif) {
4649 secmark_perm = PACKET__FORWARD_OUT;
4650 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4651 return NF_DROP;
4652 } else {
4653 secmark_perm = PACKET__SEND;
4654 peer_sid = SECINITSID_KERNEL;
4655 }
4656 } else {
4657 struct sk_security_struct *sksec = sk->sk_security;
4658 peer_sid = sksec->sid;
4659 secmark_perm = PACKET__SEND;
4660 }
4661
4662 COMMON_AUDIT_DATA_INIT(&ad, NET);
4663 ad.u.net.netif = ifindex;
4664 ad.u.net.family = family;
4665 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4666 return NF_DROP;
4667
4668 if (secmark_active)
4669 if (avc_has_perm(peer_sid, skb->secmark,
4670 SECCLASS_PACKET, secmark_perm, &ad))
4671 return NF_DROP_ERR(-ECONNREFUSED);
4672
4673 if (peerlbl_active) {
4674 u32 if_sid;
4675 u32 node_sid;
4676
4677 if (sel_netif_sid(ifindex, &if_sid))
4678 return NF_DROP;
4679 if (avc_has_perm(peer_sid, if_sid,
4680 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4681 return NF_DROP_ERR(-ECONNREFUSED);
4682
4683 if (sel_netnode_sid(addrp, family, &node_sid))
4684 return NF_DROP;
4685 if (avc_has_perm(peer_sid, node_sid,
4686 SECCLASS_NODE, NODE__SENDTO, &ad))
4687 return NF_DROP_ERR(-ECONNREFUSED);
4688 }
4689
4690 return NF_ACCEPT;
4691}
4692
4693static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4694 struct sk_buff *skb,
4695 const struct net_device *in,
4696 const struct net_device *out,
4697 int (*okfn)(struct sk_buff *))
4698{
4699 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4700}
4701
4702#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4703static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4704 struct sk_buff *skb,
4705 const struct net_device *in,
4706 const struct net_device *out,
4707 int (*okfn)(struct sk_buff *))
4708{
4709 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4710}
4711#endif /* IPV6 */
4712
4713#endif /* CONFIG_NETFILTER */
4714
4715static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4716{
4717 int err;
4718
4719 err = cap_netlink_send(sk, skb);
4720 if (err)
4721 return err;
4722
4723 return selinux_nlmsg_perm(sk, skb);
4724}
4725
4726static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4727{
4728 int err;
4729 struct common_audit_data ad;
4730 u32 sid;
4731
4732 err = cap_netlink_recv(skb, capability);
4733 if (err)
4734 return err;
4735
4736 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4737 ad.u.cap = capability;
4738
4739 security_task_getsecid(current, &sid);
4740 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4741 CAP_TO_MASK(capability), &ad);
4742}
4743
4744static int ipc_alloc_security(struct task_struct *task,
4745 struct kern_ipc_perm *perm,
4746 u16 sclass)
4747{
4748 struct ipc_security_struct *isec;
4749 u32 sid;
4750
4751 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4752 if (!isec)
4753 return -ENOMEM;
4754
4755 sid = task_sid(task);
4756 isec->sclass = sclass;
4757 isec->sid = sid;
4758 perm->security = isec;
4759
4760 return 0;
4761}
4762
4763static void ipc_free_security(struct kern_ipc_perm *perm)
4764{
4765 struct ipc_security_struct *isec = perm->security;
4766 perm->security = NULL;
4767 kfree(isec);
4768}
4769
4770static int msg_msg_alloc_security(struct msg_msg *msg)
4771{
4772 struct msg_security_struct *msec;
4773
4774 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4775 if (!msec)
4776 return -ENOMEM;
4777
4778 msec->sid = SECINITSID_UNLABELED;
4779 msg->security = msec;
4780
4781 return 0;
4782}
4783
4784static void msg_msg_free_security(struct msg_msg *msg)
4785{
4786 struct msg_security_struct *msec = msg->security;
4787
4788 msg->security = NULL;
4789 kfree(msec);
4790}
4791
4792static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4793 u32 perms)
4794{
4795 struct ipc_security_struct *isec;
4796 struct common_audit_data ad;
4797 u32 sid = current_sid();
4798
4799 isec = ipc_perms->security;
4800
4801 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4802 ad.u.ipc_id = ipc_perms->key;
4803
4804 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4805}
4806
4807static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4808{
4809 return msg_msg_alloc_security(msg);
4810}
4811
4812static void selinux_msg_msg_free_security(struct msg_msg *msg)
4813{
4814 msg_msg_free_security(msg);
4815}
4816
4817/* message queue security operations */
4818static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4819{
4820 struct ipc_security_struct *isec;
4821 struct common_audit_data ad;
4822 u32 sid = current_sid();
4823 int rc;
4824
4825 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4826 if (rc)
4827 return rc;
4828
4829 isec = msq->q_perm.security;
4830
4831 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832 ad.u.ipc_id = msq->q_perm.key;
4833
4834 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4835 MSGQ__CREATE, &ad);
4836 if (rc) {
4837 ipc_free_security(&msq->q_perm);
4838 return rc;
4839 }
4840 return 0;
4841}
4842
4843static void selinux_msg_queue_free_security(struct msg_queue *msq)
4844{
4845 ipc_free_security(&msq->q_perm);
4846}
4847
4848static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4849{
4850 struct ipc_security_struct *isec;
4851 struct common_audit_data ad;
4852 u32 sid = current_sid();
4853
4854 isec = msq->q_perm.security;
4855
4856 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4857 ad.u.ipc_id = msq->q_perm.key;
4858
4859 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4860 MSGQ__ASSOCIATE, &ad);
4861}
4862
4863static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4864{
4865 int err;
4866 int perms;
4867
4868 switch (cmd) {
4869 case IPC_INFO:
4870 case MSG_INFO:
4871 /* No specific object, just general system-wide information. */
4872 return task_has_system(current, SYSTEM__IPC_INFO);
4873 case IPC_STAT:
4874 case MSG_STAT:
4875 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4876 break;
4877 case IPC_SET:
4878 perms = MSGQ__SETATTR;
4879 break;
4880 case IPC_RMID:
4881 perms = MSGQ__DESTROY;
4882 break;
4883 default:
4884 return 0;
4885 }
4886
4887 err = ipc_has_perm(&msq->q_perm, perms);
4888 return err;
4889}
4890
4891static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4892{
4893 struct ipc_security_struct *isec;
4894 struct msg_security_struct *msec;
4895 struct common_audit_data ad;
4896 u32 sid = current_sid();
4897 int rc;
4898
4899 isec = msq->q_perm.security;
4900 msec = msg->security;
4901
4902 /*
4903 * First time through, need to assign label to the message
4904 */
4905 if (msec->sid == SECINITSID_UNLABELED) {
4906 /*
4907 * Compute new sid based on current process and
4908 * message queue this message will be stored in
4909 */
4910 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4911 NULL, &msec->sid);
4912 if (rc)
4913 return rc;
4914 }
4915
4916 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4917 ad.u.ipc_id = msq->q_perm.key;
4918
4919 /* Can this process write to the queue? */
4920 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4921 MSGQ__WRITE, &ad);
4922 if (!rc)
4923 /* Can this process send the message */
4924 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4925 MSG__SEND, &ad);
4926 if (!rc)
4927 /* Can the message be put in the queue? */
4928 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4929 MSGQ__ENQUEUE, &ad);
4930
4931 return rc;
4932}
4933
4934static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4935 struct task_struct *target,
4936 long type, int mode)
4937{
4938 struct ipc_security_struct *isec;
4939 struct msg_security_struct *msec;
4940 struct common_audit_data ad;
4941 u32 sid = task_sid(target);
4942 int rc;
4943
4944 isec = msq->q_perm.security;
4945 msec = msg->security;
4946
4947 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948 ad.u.ipc_id = msq->q_perm.key;
4949
4950 rc = avc_has_perm(sid, isec->sid,
4951 SECCLASS_MSGQ, MSGQ__READ, &ad);
4952 if (!rc)
4953 rc = avc_has_perm(sid, msec->sid,
4954 SECCLASS_MSG, MSG__RECEIVE, &ad);
4955 return rc;
4956}
4957
4958/* Shared Memory security operations */
4959static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4960{
4961 struct ipc_security_struct *isec;
4962 struct common_audit_data ad;
4963 u32 sid = current_sid();
4964 int rc;
4965
4966 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4967 if (rc)
4968 return rc;
4969
4970 isec = shp->shm_perm.security;
4971
4972 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973 ad.u.ipc_id = shp->shm_perm.key;
4974
4975 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4976 SHM__CREATE, &ad);
4977 if (rc) {
4978 ipc_free_security(&shp->shm_perm);
4979 return rc;
4980 }
4981 return 0;
4982}
4983
4984static void selinux_shm_free_security(struct shmid_kernel *shp)
4985{
4986 ipc_free_security(&shp->shm_perm);
4987}
4988
4989static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4990{
4991 struct ipc_security_struct *isec;
4992 struct common_audit_data ad;
4993 u32 sid = current_sid();
4994
4995 isec = shp->shm_perm.security;
4996
4997 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4998 ad.u.ipc_id = shp->shm_perm.key;
4999
5000 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5001 SHM__ASSOCIATE, &ad);
5002}
5003
5004/* Note, at this point, shp is locked down */
5005static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5006{
5007 int perms;
5008 int err;
5009
5010 switch (cmd) {
5011 case IPC_INFO:
5012 case SHM_INFO:
5013 /* No specific object, just general system-wide information. */
5014 return task_has_system(current, SYSTEM__IPC_INFO);
5015 case IPC_STAT:
5016 case SHM_STAT:
5017 perms = SHM__GETATTR | SHM__ASSOCIATE;
5018 break;
5019 case IPC_SET:
5020 perms = SHM__SETATTR;
5021 break;
5022 case SHM_LOCK:
5023 case SHM_UNLOCK:
5024 perms = SHM__LOCK;
5025 break;
5026 case IPC_RMID:
5027 perms = SHM__DESTROY;
5028 break;
5029 default:
5030 return 0;
5031 }
5032
5033 err = ipc_has_perm(&shp->shm_perm, perms);
5034 return err;
5035}
5036
5037static int selinux_shm_shmat(struct shmid_kernel *shp,
5038 char __user *shmaddr, int shmflg)
5039{
5040 u32 perms;
5041
5042 if (shmflg & SHM_RDONLY)
5043 perms = SHM__READ;
5044 else
5045 perms = SHM__READ | SHM__WRITE;
5046
5047 return ipc_has_perm(&shp->shm_perm, perms);
5048}
5049
5050/* Semaphore security operations */
5051static int selinux_sem_alloc_security(struct sem_array *sma)
5052{
5053 struct ipc_security_struct *isec;
5054 struct common_audit_data ad;
5055 u32 sid = current_sid();
5056 int rc;
5057
5058 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5059 if (rc)
5060 return rc;
5061
5062 isec = sma->sem_perm.security;
5063
5064 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065 ad.u.ipc_id = sma->sem_perm.key;
5066
5067 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5068 SEM__CREATE, &ad);
5069 if (rc) {
5070 ipc_free_security(&sma->sem_perm);
5071 return rc;
5072 }
5073 return 0;
5074}
5075
5076static void selinux_sem_free_security(struct sem_array *sma)
5077{
5078 ipc_free_security(&sma->sem_perm);
5079}
5080
5081static int selinux_sem_associate(struct sem_array *sma, int semflg)
5082{
5083 struct ipc_security_struct *isec;
5084 struct common_audit_data ad;
5085 u32 sid = current_sid();
5086
5087 isec = sma->sem_perm.security;
5088
5089 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5090 ad.u.ipc_id = sma->sem_perm.key;
5091
5092 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5093 SEM__ASSOCIATE, &ad);
5094}
5095
5096/* Note, at this point, sma is locked down */
5097static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5098{
5099 int err;
5100 u32 perms;
5101
5102 switch (cmd) {
5103 case IPC_INFO:
5104 case SEM_INFO:
5105 /* No specific object, just general system-wide information. */
5106 return task_has_system(current, SYSTEM__IPC_INFO);
5107 case GETPID:
5108 case GETNCNT:
5109 case GETZCNT:
5110 perms = SEM__GETATTR;
5111 break;
5112 case GETVAL:
5113 case GETALL:
5114 perms = SEM__READ;
5115 break;
5116 case SETVAL:
5117 case SETALL:
5118 perms = SEM__WRITE;
5119 break;
5120 case IPC_RMID:
5121 perms = SEM__DESTROY;
5122 break;
5123 case IPC_SET:
5124 perms = SEM__SETATTR;
5125 break;
5126 case IPC_STAT:
5127 case SEM_STAT:
5128 perms = SEM__GETATTR | SEM__ASSOCIATE;
5129 break;
5130 default:
5131 return 0;
5132 }
5133
5134 err = ipc_has_perm(&sma->sem_perm, perms);
5135 return err;
5136}
5137
5138static int selinux_sem_semop(struct sem_array *sma,
5139 struct sembuf *sops, unsigned nsops, int alter)
5140{
5141 u32 perms;
5142
5143 if (alter)
5144 perms = SEM__READ | SEM__WRITE;
5145 else
5146 perms = SEM__READ;
5147
5148 return ipc_has_perm(&sma->sem_perm, perms);
5149}
5150
5151static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5152{
5153 u32 av = 0;
5154
5155 av = 0;
5156 if (flag & S_IRUGO)
5157 av |= IPC__UNIX_READ;
5158 if (flag & S_IWUGO)
5159 av |= IPC__UNIX_WRITE;
5160
5161 if (av == 0)
5162 return 0;
5163
5164 return ipc_has_perm(ipcp, av);
5165}
5166
5167static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5168{
5169 struct ipc_security_struct *isec = ipcp->security;
5170 *secid = isec->sid;
5171}
5172
5173static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5174{
5175 if (inode)
5176 inode_doinit_with_dentry(inode, dentry);
5177}
5178
5179static int selinux_getprocattr(struct task_struct *p,
5180 char *name, char **value)
5181{
5182 const struct task_security_struct *__tsec;
5183 u32 sid;
5184 int error;
5185 unsigned len;
5186
5187 if (current != p) {
5188 error = current_has_perm(p, PROCESS__GETATTR);
5189 if (error)
5190 return error;
5191 }
5192
5193 rcu_read_lock();
5194 __tsec = __task_cred(p)->security;
5195
5196 if (!strcmp(name, "current"))
5197 sid = __tsec->sid;
5198 else if (!strcmp(name, "prev"))
5199 sid = __tsec->osid;
5200 else if (!strcmp(name, "exec"))
5201 sid = __tsec->exec_sid;
5202 else if (!strcmp(name, "fscreate"))
5203 sid = __tsec->create_sid;
5204 else if (!strcmp(name, "keycreate"))
5205 sid = __tsec->keycreate_sid;
5206 else if (!strcmp(name, "sockcreate"))
5207 sid = __tsec->sockcreate_sid;
5208 else
5209 goto invalid;
5210 rcu_read_unlock();
5211
5212 if (!sid)
5213 return 0;
5214
5215 error = security_sid_to_context(sid, value, &len);
5216 if (error)
5217 return error;
5218 return len;
5219
5220invalid:
5221 rcu_read_unlock();
5222 return -EINVAL;
5223}
5224
5225static int selinux_setprocattr(struct task_struct *p,
5226 char *name, void *value, size_t size)
5227{
5228 struct task_security_struct *tsec;
5229 struct task_struct *tracer;
5230 struct cred *new;
5231 u32 sid = 0, ptsid;
5232 int error;
5233 char *str = value;
5234
5235 if (current != p) {
5236 /* SELinux only allows a process to change its own
5237 security attributes. */
5238 return -EACCES;
5239 }
5240
5241 /*
5242 * Basic control over ability to set these attributes at all.
5243 * current == p, but we'll pass them separately in case the
5244 * above restriction is ever removed.
5245 */
5246 if (!strcmp(name, "exec"))
5247 error = current_has_perm(p, PROCESS__SETEXEC);
5248 else if (!strcmp(name, "fscreate"))
5249 error = current_has_perm(p, PROCESS__SETFSCREATE);
5250 else if (!strcmp(name, "keycreate"))
5251 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252 else if (!strcmp(name, "sockcreate"))
5253 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5254 else if (!strcmp(name, "current"))
5255 error = current_has_perm(p, PROCESS__SETCURRENT);
5256 else
5257 error = -EINVAL;
5258 if (error)
5259 return error;
5260
5261 /* Obtain a SID for the context, if one was specified. */
5262 if (size && str[1] && str[1] != '\n') {
5263 if (str[size-1] == '\n') {
5264 str[size-1] = 0;
5265 size--;
5266 }
5267 error = security_context_to_sid(value, size, &sid);
5268 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5269 if (!capable(CAP_MAC_ADMIN))
5270 return error;
5271 error = security_context_to_sid_force(value, size,
5272 &sid);
5273 }
5274 if (error)
5275 return error;
5276 }
5277
5278 new = prepare_creds();
5279 if (!new)
5280 return -ENOMEM;
5281
5282 /* Permission checking based on the specified context is
5283 performed during the actual operation (execve,
5284 open/mkdir/...), when we know the full context of the
5285 operation. See selinux_bprm_set_creds for the execve
5286 checks and may_create for the file creation checks. The
5287 operation will then fail if the context is not permitted. */
5288 tsec = new->security;
5289 if (!strcmp(name, "exec")) {
5290 tsec->exec_sid = sid;
5291 } else if (!strcmp(name, "fscreate")) {
5292 tsec->create_sid = sid;
5293 } else if (!strcmp(name, "keycreate")) {
5294 error = may_create_key(sid, p);
5295 if (error)
5296 goto abort_change;
5297 tsec->keycreate_sid = sid;
5298 } else if (!strcmp(name, "sockcreate")) {
5299 tsec->sockcreate_sid = sid;
5300 } else if (!strcmp(name, "current")) {
5301 error = -EINVAL;
5302 if (sid == 0)
5303 goto abort_change;
5304
5305 /* Only allow single threaded processes to change context */
5306 error = -EPERM;
5307 if (!current_is_single_threaded()) {
5308 error = security_bounded_transition(tsec->sid, sid);
5309 if (error)
5310 goto abort_change;
5311 }
5312
5313 /* Check permissions for the transition. */
5314 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315 PROCESS__DYNTRANSITION, NULL);
5316 if (error)
5317 goto abort_change;
5318
5319 /* Check for ptracing, and update the task SID if ok.
5320 Otherwise, leave SID unchanged and fail. */
5321 ptsid = 0;
5322 task_lock(p);
5323 tracer = ptrace_parent(p);
5324 if (tracer)
5325 ptsid = task_sid(tracer);
5326 task_unlock(p);
5327
5328 if (tracer) {
5329 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5330 PROCESS__PTRACE, NULL);
5331 if (error)
5332 goto abort_change;
5333 }
5334
5335 tsec->sid = sid;
5336 } else {
5337 error = -EINVAL;
5338 goto abort_change;
5339 }
5340
5341 commit_creds(new);
5342 return size;
5343
5344abort_change:
5345 abort_creds(new);
5346 return error;
5347}
5348
5349static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5350{
5351 return security_sid_to_context(secid, secdata, seclen);
5352}
5353
5354static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355{
5356 return security_context_to_sid(secdata, seclen, secid);
5357}
5358
5359static void selinux_release_secctx(char *secdata, u32 seclen)
5360{
5361 kfree(secdata);
5362}
5363
5364/*
5365 * called with inode->i_mutex locked
5366 */
5367static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5368{
5369 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5370}
5371
5372/*
5373 * called with inode->i_mutex locked
5374 */
5375static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5376{
5377 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5378}
5379
5380static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5381{
5382 int len = 0;
5383 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5384 ctx, true);
5385 if (len < 0)
5386 return len;
5387 *ctxlen = len;
5388 return 0;
5389}
5390#ifdef CONFIG_KEYS
5391
5392static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393 unsigned long flags)
5394{
5395 const struct task_security_struct *tsec;
5396 struct key_security_struct *ksec;
5397
5398 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5399 if (!ksec)
5400 return -ENOMEM;
5401
5402 tsec = cred->security;
5403 if (tsec->keycreate_sid)
5404 ksec->sid = tsec->keycreate_sid;
5405 else
5406 ksec->sid = tsec->sid;
5407
5408 k->security = ksec;
5409 return 0;
5410}
5411
5412static void selinux_key_free(struct key *k)
5413{
5414 struct key_security_struct *ksec = k->security;
5415
5416 k->security = NULL;
5417 kfree(ksec);
5418}
5419
5420static int selinux_key_permission(key_ref_t key_ref,
5421 const struct cred *cred,
5422 key_perm_t perm)
5423{
5424 struct key *key;
5425 struct key_security_struct *ksec;
5426 u32 sid;
5427
5428 /* if no specific permissions are requested, we skip the
5429 permission check. No serious, additional covert channels
5430 appear to be created. */
5431 if (perm == 0)
5432 return 0;
5433
5434 sid = cred_sid(cred);
5435
5436 key = key_ref_to_ptr(key_ref);
5437 ksec = key->security;
5438
5439 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440}
5441
5442static int selinux_key_getsecurity(struct key *key, char **_buffer)
5443{
5444 struct key_security_struct *ksec = key->security;
5445 char *context = NULL;
5446 unsigned len;
5447 int rc;
5448
5449 rc = security_sid_to_context(ksec->sid, &context, &len);
5450 if (!rc)
5451 rc = len;
5452 *_buffer = context;
5453 return rc;
5454}
5455
5456#endif
5457
5458static struct security_operations selinux_ops = {
5459 .name = "selinux",
5460
5461 .ptrace_access_check = selinux_ptrace_access_check,
5462 .ptrace_traceme = selinux_ptrace_traceme,
5463 .capget = selinux_capget,
5464 .capset = selinux_capset,
5465 .capable = selinux_capable,
5466 .quotactl = selinux_quotactl,
5467 .quota_on = selinux_quota_on,
5468 .syslog = selinux_syslog,
5469 .vm_enough_memory = selinux_vm_enough_memory,
5470
5471 .netlink_send = selinux_netlink_send,
5472 .netlink_recv = selinux_netlink_recv,
5473
5474 .bprm_set_creds = selinux_bprm_set_creds,
5475 .bprm_committing_creds = selinux_bprm_committing_creds,
5476 .bprm_committed_creds = selinux_bprm_committed_creds,
5477 .bprm_secureexec = selinux_bprm_secureexec,
5478
5479 .sb_alloc_security = selinux_sb_alloc_security,
5480 .sb_free_security = selinux_sb_free_security,
5481 .sb_copy_data = selinux_sb_copy_data,
5482 .sb_remount = selinux_sb_remount,
5483 .sb_kern_mount = selinux_sb_kern_mount,
5484 .sb_show_options = selinux_sb_show_options,
5485 .sb_statfs = selinux_sb_statfs,
5486 .sb_mount = selinux_mount,
5487 .sb_umount = selinux_umount,
5488 .sb_set_mnt_opts = selinux_set_mnt_opts,
5489 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5490 .sb_parse_opts_str = selinux_parse_opts_str,
5491
5492
5493 .inode_alloc_security = selinux_inode_alloc_security,
5494 .inode_free_security = selinux_inode_free_security,
5495 .inode_init_security = selinux_inode_init_security,
5496 .inode_create = selinux_inode_create,
5497 .inode_link = selinux_inode_link,
5498 .inode_unlink = selinux_inode_unlink,
5499 .inode_symlink = selinux_inode_symlink,
5500 .inode_mkdir = selinux_inode_mkdir,
5501 .inode_rmdir = selinux_inode_rmdir,
5502 .inode_mknod = selinux_inode_mknod,
5503 .inode_rename = selinux_inode_rename,
5504 .inode_readlink = selinux_inode_readlink,
5505 .inode_follow_link = selinux_inode_follow_link,
5506 .inode_permission = selinux_inode_permission,
5507 .inode_setattr = selinux_inode_setattr,
5508 .inode_getattr = selinux_inode_getattr,
5509 .inode_setxattr = selinux_inode_setxattr,
5510 .inode_post_setxattr = selinux_inode_post_setxattr,
5511 .inode_getxattr = selinux_inode_getxattr,
5512 .inode_listxattr = selinux_inode_listxattr,
5513 .inode_removexattr = selinux_inode_removexattr,
5514 .inode_getsecurity = selinux_inode_getsecurity,
5515 .inode_setsecurity = selinux_inode_setsecurity,
5516 .inode_listsecurity = selinux_inode_listsecurity,
5517 .inode_getsecid = selinux_inode_getsecid,
5518
5519 .file_permission = selinux_file_permission,
5520 .file_alloc_security = selinux_file_alloc_security,
5521 .file_free_security = selinux_file_free_security,
5522 .file_ioctl = selinux_file_ioctl,
5523 .file_mmap = selinux_file_mmap,
5524 .file_mprotect = selinux_file_mprotect,
5525 .file_lock = selinux_file_lock,
5526 .file_fcntl = selinux_file_fcntl,
5527 .file_set_fowner = selinux_file_set_fowner,
5528 .file_send_sigiotask = selinux_file_send_sigiotask,
5529 .file_receive = selinux_file_receive,
5530
5531 .dentry_open = selinux_dentry_open,
5532
5533 .task_create = selinux_task_create,
5534 .cred_alloc_blank = selinux_cred_alloc_blank,
5535 .cred_free = selinux_cred_free,
5536 .cred_prepare = selinux_cred_prepare,
5537 .cred_transfer = selinux_cred_transfer,
5538 .kernel_act_as = selinux_kernel_act_as,
5539 .kernel_create_files_as = selinux_kernel_create_files_as,
5540 .kernel_module_request = selinux_kernel_module_request,
5541 .task_setpgid = selinux_task_setpgid,
5542 .task_getpgid = selinux_task_getpgid,
5543 .task_getsid = selinux_task_getsid,
5544 .task_getsecid = selinux_task_getsecid,
5545 .task_setnice = selinux_task_setnice,
5546 .task_setioprio = selinux_task_setioprio,
5547 .task_getioprio = selinux_task_getioprio,
5548 .task_setrlimit = selinux_task_setrlimit,
5549 .task_setscheduler = selinux_task_setscheduler,
5550 .task_getscheduler = selinux_task_getscheduler,
5551 .task_movememory = selinux_task_movememory,
5552 .task_kill = selinux_task_kill,
5553 .task_wait = selinux_task_wait,
5554 .task_to_inode = selinux_task_to_inode,
5555
5556 .ipc_permission = selinux_ipc_permission,
5557 .ipc_getsecid = selinux_ipc_getsecid,
5558
5559 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5560 .msg_msg_free_security = selinux_msg_msg_free_security,
5561
5562 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5563 .msg_queue_free_security = selinux_msg_queue_free_security,
5564 .msg_queue_associate = selinux_msg_queue_associate,
5565 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5566 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5567 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5568
5569 .shm_alloc_security = selinux_shm_alloc_security,
5570 .shm_free_security = selinux_shm_free_security,
5571 .shm_associate = selinux_shm_associate,
5572 .shm_shmctl = selinux_shm_shmctl,
5573 .shm_shmat = selinux_shm_shmat,
5574
5575 .sem_alloc_security = selinux_sem_alloc_security,
5576 .sem_free_security = selinux_sem_free_security,
5577 .sem_associate = selinux_sem_associate,
5578 .sem_semctl = selinux_sem_semctl,
5579 .sem_semop = selinux_sem_semop,
5580
5581 .d_instantiate = selinux_d_instantiate,
5582
5583 .getprocattr = selinux_getprocattr,
5584 .setprocattr = selinux_setprocattr,
5585
5586 .secid_to_secctx = selinux_secid_to_secctx,
5587 .secctx_to_secid = selinux_secctx_to_secid,
5588 .release_secctx = selinux_release_secctx,
5589 .inode_notifysecctx = selinux_inode_notifysecctx,
5590 .inode_setsecctx = selinux_inode_setsecctx,
5591 .inode_getsecctx = selinux_inode_getsecctx,
5592
5593 .unix_stream_connect = selinux_socket_unix_stream_connect,
5594 .unix_may_send = selinux_socket_unix_may_send,
5595
5596 .socket_create = selinux_socket_create,
5597 .socket_post_create = selinux_socket_post_create,
5598 .socket_bind = selinux_socket_bind,
5599 .socket_connect = selinux_socket_connect,
5600 .socket_listen = selinux_socket_listen,
5601 .socket_accept = selinux_socket_accept,
5602 .socket_sendmsg = selinux_socket_sendmsg,
5603 .socket_recvmsg = selinux_socket_recvmsg,
5604 .socket_getsockname = selinux_socket_getsockname,
5605 .socket_getpeername = selinux_socket_getpeername,
5606 .socket_getsockopt = selinux_socket_getsockopt,
5607 .socket_setsockopt = selinux_socket_setsockopt,
5608 .socket_shutdown = selinux_socket_shutdown,
5609 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5610 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5611 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5612 .sk_alloc_security = selinux_sk_alloc_security,
5613 .sk_free_security = selinux_sk_free_security,
5614 .sk_clone_security = selinux_sk_clone_security,
5615 .sk_getsecid = selinux_sk_getsecid,
5616 .sock_graft = selinux_sock_graft,
5617 .inet_conn_request = selinux_inet_conn_request,
5618 .inet_csk_clone = selinux_inet_csk_clone,
5619 .inet_conn_established = selinux_inet_conn_established,
5620 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5621 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5622 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5623 .req_classify_flow = selinux_req_classify_flow,
5624 .tun_dev_create = selinux_tun_dev_create,
5625 .tun_dev_post_create = selinux_tun_dev_post_create,
5626 .tun_dev_attach = selinux_tun_dev_attach,
5627
5628#ifdef CONFIG_SECURITY_NETWORK_XFRM
5629 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5630 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5631 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5632 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5633 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5634 .xfrm_state_free_security = selinux_xfrm_state_free,
5635 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5636 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5637 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5638 .xfrm_decode_session = selinux_xfrm_decode_session,
5639#endif
5640
5641#ifdef CONFIG_KEYS
5642 .key_alloc = selinux_key_alloc,
5643 .key_free = selinux_key_free,
5644 .key_permission = selinux_key_permission,
5645 .key_getsecurity = selinux_key_getsecurity,
5646#endif
5647
5648#ifdef CONFIG_AUDIT
5649 .audit_rule_init = selinux_audit_rule_init,
5650 .audit_rule_known = selinux_audit_rule_known,
5651 .audit_rule_match = selinux_audit_rule_match,
5652 .audit_rule_free = selinux_audit_rule_free,
5653#endif
5654};
5655
5656static __init int selinux_init(void)
5657{
5658 if (!security_module_enable(&selinux_ops)) {
5659 selinux_enabled = 0;
5660 return 0;
5661 }
5662
5663 if (!selinux_enabled) {
5664 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5665 return 0;
5666 }
5667
5668 printk(KERN_INFO "SELinux: Initializing.\n");
5669
5670 /* Set the security state for the initial task. */
5671 cred_init_security();
5672
5673 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5674
5675 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5676 sizeof(struct inode_security_struct),
5677 0, SLAB_PANIC, NULL);
5678 avc_init();
5679
5680 if (register_security(&selinux_ops))
5681 panic("SELinux: Unable to register with kernel.\n");
5682
5683 if (selinux_enforcing)
5684 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5685 else
5686 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5687
5688 return 0;
5689}
5690
5691static void delayed_superblock_init(struct super_block *sb, void *unused)
5692{
5693 superblock_doinit(sb, NULL);
5694}
5695
5696void selinux_complete_init(void)
5697{
5698 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5699
5700 /* Set up any superblocks initialized prior to the policy load. */
5701 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5702 iterate_supers(delayed_superblock_init, NULL);
5703}
5704
5705/* SELinux requires early initialization in order to label
5706 all processes and objects when they are created. */
5707security_initcall(selinux_init);
5708
5709#if defined(CONFIG_NETFILTER)
5710
5711static struct nf_hook_ops selinux_ipv4_ops[] = {
5712 {
5713 .hook = selinux_ipv4_postroute,
5714 .owner = THIS_MODULE,
5715 .pf = PF_INET,
5716 .hooknum = NF_INET_POST_ROUTING,
5717 .priority = NF_IP_PRI_SELINUX_LAST,
5718 },
5719 {
5720 .hook = selinux_ipv4_forward,
5721 .owner = THIS_MODULE,
5722 .pf = PF_INET,
5723 .hooknum = NF_INET_FORWARD,
5724 .priority = NF_IP_PRI_SELINUX_FIRST,
5725 },
5726 {
5727 .hook = selinux_ipv4_output,
5728 .owner = THIS_MODULE,
5729 .pf = PF_INET,
5730 .hooknum = NF_INET_LOCAL_OUT,
5731 .priority = NF_IP_PRI_SELINUX_FIRST,
5732 }
5733};
5734
5735#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5736
5737static struct nf_hook_ops selinux_ipv6_ops[] = {
5738 {
5739 .hook = selinux_ipv6_postroute,
5740 .owner = THIS_MODULE,
5741 .pf = PF_INET6,
5742 .hooknum = NF_INET_POST_ROUTING,
5743 .priority = NF_IP6_PRI_SELINUX_LAST,
5744 },
5745 {
5746 .hook = selinux_ipv6_forward,
5747 .owner = THIS_MODULE,
5748 .pf = PF_INET6,
5749 .hooknum = NF_INET_FORWARD,
5750 .priority = NF_IP6_PRI_SELINUX_FIRST,
5751 }
5752};
5753
5754#endif /* IPV6 */
5755
5756static int __init selinux_nf_ip_init(void)
5757{
5758 int err = 0;
5759
5760 if (!selinux_enabled)
5761 goto out;
5762
5763 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5764
5765 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5766 if (err)
5767 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5768
5769#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5770 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5771 if (err)
5772 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5773#endif /* IPV6 */
5774
5775out:
5776 return err;
5777}
5778
5779__initcall(selinux_nf_ip_init);
5780
5781#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5782static void selinux_nf_ip_exit(void)
5783{
5784 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5785
5786 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5787#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5788 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5789#endif /* IPV6 */
5790}
5791#endif
5792
5793#else /* CONFIG_NETFILTER */
5794
5795#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796#define selinux_nf_ip_exit()
5797#endif
5798
5799#endif /* CONFIG_NETFILTER */
5800
5801#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5802static int selinux_disabled;
5803
5804int selinux_disable(void)
5805{
5806 extern void exit_sel_fs(void);
5807
5808 if (ss_initialized) {
5809 /* Not permitted after initial policy load. */
5810 return -EINVAL;
5811 }
5812
5813 if (selinux_disabled) {
5814 /* Only do this once. */
5815 return -EINVAL;
5816 }
5817
5818 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5819
5820 selinux_disabled = 1;
5821 selinux_enabled = 0;
5822
5823 reset_security_ops();
5824
5825 /* Try to destroy the avc node cache */
5826 avc_disable();
5827
5828 /* Unregister netfilter hooks. */
5829 selinux_nf_ip_exit();
5830
5831 /* Unregister selinuxfs. */
5832 exit_sel_fs();
5833
5834 return 0;
5835}
5836#endif