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