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1/*
2 * NSA Security-Enhanced Linux (SELinux) security module
3 *
4 * This file contains the SELinux hook function implementations.
5 *
6 * Authors: Stephen Smalley, <sds@epoch.ncsc.mil>
7 * Chris Vance, <cvance@nai.com>
8 * Wayne Salamon, <wsalamon@nai.com>
9 * James Morris <jmorris@redhat.com>
10 *
11 * Copyright (C) 2001,2002 Networks Associates Technology, Inc.
12 * Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
13 * Eric Paris <eparis@redhat.com>
14 * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
15 * <dgoeddel@trustedcs.com>
16 * Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
17 * Paul Moore <paul@paul-moore.com>
18 * Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
19 * Yuichi Nakamura <ynakam@hitachisoft.jp>
20 *
21 * This program is free software; you can redistribute it and/or modify
22 * it under the terms of the GNU General Public License version 2,
23 * as published by the Free Software Foundation.
24 */
25
26#include <linux/init.h>
27#include <linux/kd.h>
28#include <linux/kernel.h>
29#include <linux/tracehook.h>
30#include <linux/errno.h>
31#include <linux/ext2_fs.h>
32#include <linux/sched.h>
33#include <linux/security.h>
34#include <linux/xattr.h>
35#include <linux/capability.h>
36#include <linux/unistd.h>
37#include <linux/mm.h>
38#include <linux/mman.h>
39#include <linux/slab.h>
40#include <linux/pagemap.h>
41#include <linux/proc_fs.h>
42#include <linux/swap.h>
43#include <linux/spinlock.h>
44#include <linux/syscalls.h>
45#include <linux/dcache.h>
46#include <linux/file.h>
47#include <linux/fdtable.h>
48#include <linux/namei.h>
49#include <linux/mount.h>
50#include <linux/netfilter_ipv4.h>
51#include <linux/netfilter_ipv6.h>
52#include <linux/tty.h>
53#include <net/icmp.h>
54#include <net/ip.h> /* for local_port_range[] */
55#include <net/tcp.h> /* struct or_callable used in sock_rcv_skb */
56#include <net/net_namespace.h>
57#include <net/netlabel.h>
58#include <linux/uaccess.h>
59#include <asm/ioctls.h>
60#include <linux/atomic.h>
61#include <linux/bitops.h>
62#include <linux/interrupt.h>
63#include <linux/netdevice.h> /* for network interface checks */
64#include <linux/netlink.h>
65#include <linux/tcp.h>
66#include <linux/udp.h>
67#include <linux/dccp.h>
68#include <linux/quota.h>
69#include <linux/un.h> /* for Unix socket types */
70#include <net/af_unix.h> /* for Unix socket types */
71#include <linux/parser.h>
72#include <linux/nfs_mount.h>
73#include <net/ipv6.h>
74#include <linux/hugetlb.h>
75#include <linux/personality.h>
76#include <linux/audit.h>
77#include <linux/string.h>
78#include <linux/selinux.h>
79#include <linux/mutex.h>
80#include <linux/posix-timers.h>
81#include <linux/syslog.h>
82#include <linux/user_namespace.h>
83
84#include "avc.h"
85#include "objsec.h"
86#include "netif.h"
87#include "netnode.h"
88#include "netport.h"
89#include "xfrm.h"
90#include "netlabel.h"
91#include "audit.h"
92
93#define NUM_SEL_MNT_OPTS 5
94
95extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
96extern struct security_operations *security_ops;
97
98/* SECMARK reference count */
99atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
100
101#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
102int selinux_enforcing;
103
104static int __init enforcing_setup(char *str)
105{
106 unsigned long enforcing;
107 if (!strict_strtoul(str, 0, &enforcing))
108 selinux_enforcing = enforcing ? 1 : 0;
109 return 1;
110}
111__setup("enforcing=", enforcing_setup);
112#endif
113
114#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
115int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
116
117static int __init selinux_enabled_setup(char *str)
118{
119 unsigned long enabled;
120 if (!strict_strtoul(str, 0, &enabled))
121 selinux_enabled = enabled ? 1 : 0;
122 return 1;
123}
124__setup("selinux=", selinux_enabled_setup);
125#else
126int selinux_enabled = 1;
127#endif
128
129static struct kmem_cache *sel_inode_cache;
130
131/**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled.
139 *
140 */
141static int selinux_secmark_enabled(void)
142{
143 return (atomic_read(&selinux_secmark_refcount) > 0);
144}
145
146/*
147 * initialise the security for the init task
148 */
149static void cred_init_security(void)
150{
151 struct cred *cred = (struct cred *) current->real_cred;
152 struct task_security_struct *tsec;
153
154 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
155 if (!tsec)
156 panic("SELinux: Failed to initialize initial task.\n");
157
158 tsec->osid = tsec->sid = SECINITSID_KERNEL;
159 cred->security = tsec;
160}
161
162/*
163 * get the security ID of a set of credentials
164 */
165static inline u32 cred_sid(const struct cred *cred)
166{
167 const struct task_security_struct *tsec;
168
169 tsec = cred->security;
170 return tsec->sid;
171}
172
173/*
174 * get the objective security ID of a task
175 */
176static inline u32 task_sid(const struct task_struct *task)
177{
178 u32 sid;
179
180 rcu_read_lock();
181 sid = cred_sid(__task_cred(task));
182 rcu_read_unlock();
183 return sid;
184}
185
186/*
187 * get the subjective security ID of the current task
188 */
189static inline u32 current_sid(void)
190{
191 const struct task_security_struct *tsec = current_security();
192
193 return tsec->sid;
194}
195
196/* Allocate and free functions for each kind of security blob. */
197
198static int inode_alloc_security(struct inode *inode)
199{
200 struct inode_security_struct *isec;
201 u32 sid = current_sid();
202
203 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
204 if (!isec)
205 return -ENOMEM;
206
207 mutex_init(&isec->lock);
208 INIT_LIST_HEAD(&isec->list);
209 isec->inode = inode;
210 isec->sid = SECINITSID_UNLABELED;
211 isec->sclass = SECCLASS_FILE;
212 isec->task_sid = sid;
213 inode->i_security = isec;
214
215 return 0;
216}
217
218static void inode_free_security(struct inode *inode)
219{
220 struct inode_security_struct *isec = inode->i_security;
221 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
222
223 spin_lock(&sbsec->isec_lock);
224 if (!list_empty(&isec->list))
225 list_del_init(&isec->list);
226 spin_unlock(&sbsec->isec_lock);
227
228 inode->i_security = NULL;
229 kmem_cache_free(sel_inode_cache, isec);
230}
231
232static int file_alloc_security(struct file *file)
233{
234 struct file_security_struct *fsec;
235 u32 sid = current_sid();
236
237 fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
238 if (!fsec)
239 return -ENOMEM;
240
241 fsec->sid = sid;
242 fsec->fown_sid = sid;
243 file->f_security = fsec;
244
245 return 0;
246}
247
248static void file_free_security(struct file *file)
249{
250 struct file_security_struct *fsec = file->f_security;
251 file->f_security = NULL;
252 kfree(fsec);
253}
254
255static int superblock_alloc_security(struct super_block *sb)
256{
257 struct superblock_security_struct *sbsec;
258
259 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
260 if (!sbsec)
261 return -ENOMEM;
262
263 mutex_init(&sbsec->lock);
264 INIT_LIST_HEAD(&sbsec->isec_head);
265 spin_lock_init(&sbsec->isec_lock);
266 sbsec->sb = sb;
267 sbsec->sid = SECINITSID_UNLABELED;
268 sbsec->def_sid = SECINITSID_FILE;
269 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
270 sb->s_security = sbsec;
271
272 return 0;
273}
274
275static void superblock_free_security(struct super_block *sb)
276{
277 struct superblock_security_struct *sbsec = sb->s_security;
278 sb->s_security = NULL;
279 kfree(sbsec);
280}
281
282/* The security server must be initialized before
283 any labeling or access decisions can be provided. */
284extern int ss_initialized;
285
286/* The file system's label must be initialized prior to use. */
287
288static const char *labeling_behaviors[6] = {
289 "uses xattr",
290 "uses transition SIDs",
291 "uses task SIDs",
292 "uses genfs_contexts",
293 "not configured for labeling",
294 "uses mountpoint labeling",
295};
296
297static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
298
299static inline int inode_doinit(struct inode *inode)
300{
301 return inode_doinit_with_dentry(inode, NULL);
302}
303
304enum {
305 Opt_error = -1,
306 Opt_context = 1,
307 Opt_fscontext = 2,
308 Opt_defcontext = 3,
309 Opt_rootcontext = 4,
310 Opt_labelsupport = 5,
311};
312
313static const match_table_t tokens = {
314 {Opt_context, CONTEXT_STR "%s"},
315 {Opt_fscontext, FSCONTEXT_STR "%s"},
316 {Opt_defcontext, DEFCONTEXT_STR "%s"},
317 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
318 {Opt_labelsupport, LABELSUPP_STR},
319 {Opt_error, NULL},
320};
321
322#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
323
324static int may_context_mount_sb_relabel(u32 sid,
325 struct superblock_security_struct *sbsec,
326 const struct cred *cred)
327{
328 const struct task_security_struct *tsec = cred->security;
329 int rc;
330
331 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
332 FILESYSTEM__RELABELFROM, NULL);
333 if (rc)
334 return rc;
335
336 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
337 FILESYSTEM__RELABELTO, NULL);
338 return rc;
339}
340
341static int may_context_mount_inode_relabel(u32 sid,
342 struct superblock_security_struct *sbsec,
343 const struct cred *cred)
344{
345 const struct task_security_struct *tsec = cred->security;
346 int rc;
347 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
348 FILESYSTEM__RELABELFROM, NULL);
349 if (rc)
350 return rc;
351
352 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
353 FILESYSTEM__ASSOCIATE, NULL);
354 return rc;
355}
356
357static int sb_finish_set_opts(struct super_block *sb)
358{
359 struct superblock_security_struct *sbsec = sb->s_security;
360 struct dentry *root = sb->s_root;
361 struct inode *root_inode = root->d_inode;
362 int rc = 0;
363
364 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
365 /* Make sure that the xattr handler exists and that no
366 error other than -ENODATA is returned by getxattr on
367 the root directory. -ENODATA is ok, as this may be
368 the first boot of the SELinux kernel before we have
369 assigned xattr values to the filesystem. */
370 if (!root_inode->i_op->getxattr) {
371 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
372 "xattr support\n", sb->s_id, sb->s_type->name);
373 rc = -EOPNOTSUPP;
374 goto out;
375 }
376 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
377 if (rc < 0 && rc != -ENODATA) {
378 if (rc == -EOPNOTSUPP)
379 printk(KERN_WARNING "SELinux: (dev %s, type "
380 "%s) has no security xattr handler\n",
381 sb->s_id, sb->s_type->name);
382 else
383 printk(KERN_WARNING "SELinux: (dev %s, type "
384 "%s) getxattr errno %d\n", sb->s_id,
385 sb->s_type->name, -rc);
386 goto out;
387 }
388 }
389
390 sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
391
392 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
393 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
394 sb->s_id, sb->s_type->name);
395 else
396 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
397 sb->s_id, sb->s_type->name,
398 labeling_behaviors[sbsec->behavior-1]);
399
400 if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
401 sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
402 sbsec->behavior == SECURITY_FS_USE_NONE ||
403 sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
404 sbsec->flags &= ~SE_SBLABELSUPP;
405
406 /* Special handling for sysfs. Is genfs but also has setxattr handler*/
407 if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
408 sbsec->flags |= SE_SBLABELSUPP;
409
410 /* Initialize the root inode. */
411 rc = inode_doinit_with_dentry(root_inode, root);
412
413 /* Initialize any other inodes associated with the superblock, e.g.
414 inodes created prior to initial policy load or inodes created
415 during get_sb by a pseudo filesystem that directly
416 populates itself. */
417 spin_lock(&sbsec->isec_lock);
418next_inode:
419 if (!list_empty(&sbsec->isec_head)) {
420 struct inode_security_struct *isec =
421 list_entry(sbsec->isec_head.next,
422 struct inode_security_struct, list);
423 struct inode *inode = isec->inode;
424 spin_unlock(&sbsec->isec_lock);
425 inode = igrab(inode);
426 if (inode) {
427 if (!IS_PRIVATE(inode))
428 inode_doinit(inode);
429 iput(inode);
430 }
431 spin_lock(&sbsec->isec_lock);
432 list_del_init(&isec->list);
433 goto next_inode;
434 }
435 spin_unlock(&sbsec->isec_lock);
436out:
437 return rc;
438}
439
440/*
441 * This function should allow an FS to ask what it's mount security
442 * options were so it can use those later for submounts, displaying
443 * mount options, or whatever.
444 */
445static int selinux_get_mnt_opts(const struct super_block *sb,
446 struct security_mnt_opts *opts)
447{
448 int rc = 0, i;
449 struct superblock_security_struct *sbsec = sb->s_security;
450 char *context = NULL;
451 u32 len;
452 char tmp;
453
454 security_init_mnt_opts(opts);
455
456 if (!(sbsec->flags & SE_SBINITIALIZED))
457 return -EINVAL;
458
459 if (!ss_initialized)
460 return -EINVAL;
461
462 tmp = sbsec->flags & SE_MNTMASK;
463 /* count the number of mount options for this sb */
464 for (i = 0; i < 8; i++) {
465 if (tmp & 0x01)
466 opts->num_mnt_opts++;
467 tmp >>= 1;
468 }
469 /* Check if the Label support flag is set */
470 if (sbsec->flags & SE_SBLABELSUPP)
471 opts->num_mnt_opts++;
472
473 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
474 if (!opts->mnt_opts) {
475 rc = -ENOMEM;
476 goto out_free;
477 }
478
479 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
480 if (!opts->mnt_opts_flags) {
481 rc = -ENOMEM;
482 goto out_free;
483 }
484
485 i = 0;
486 if (sbsec->flags & FSCONTEXT_MNT) {
487 rc = security_sid_to_context(sbsec->sid, &context, &len);
488 if (rc)
489 goto out_free;
490 opts->mnt_opts[i] = context;
491 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
492 }
493 if (sbsec->flags & CONTEXT_MNT) {
494 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
495 if (rc)
496 goto out_free;
497 opts->mnt_opts[i] = context;
498 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
499 }
500 if (sbsec->flags & DEFCONTEXT_MNT) {
501 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
502 if (rc)
503 goto out_free;
504 opts->mnt_opts[i] = context;
505 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
506 }
507 if (sbsec->flags & ROOTCONTEXT_MNT) {
508 struct inode *root = sbsec->sb->s_root->d_inode;
509 struct inode_security_struct *isec = root->i_security;
510
511 rc = security_sid_to_context(isec->sid, &context, &len);
512 if (rc)
513 goto out_free;
514 opts->mnt_opts[i] = context;
515 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
516 }
517 if (sbsec->flags & SE_SBLABELSUPP) {
518 opts->mnt_opts[i] = NULL;
519 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
520 }
521
522 BUG_ON(i != opts->num_mnt_opts);
523
524 return 0;
525
526out_free:
527 security_free_mnt_opts(opts);
528 return rc;
529}
530
531static int bad_option(struct superblock_security_struct *sbsec, char flag,
532 u32 old_sid, u32 new_sid)
533{
534 char mnt_flags = sbsec->flags & SE_MNTMASK;
535
536 /* check if the old mount command had the same options */
537 if (sbsec->flags & SE_SBINITIALIZED)
538 if (!(sbsec->flags & flag) ||
539 (old_sid != new_sid))
540 return 1;
541
542 /* check if we were passed the same options twice,
543 * aka someone passed context=a,context=b
544 */
545 if (!(sbsec->flags & SE_SBINITIALIZED))
546 if (mnt_flags & flag)
547 return 1;
548 return 0;
549}
550
551/*
552 * Allow filesystems with binary mount data to explicitly set mount point
553 * labeling information.
554 */
555static int selinux_set_mnt_opts(struct super_block *sb,
556 struct security_mnt_opts *opts)
557{
558 const struct cred *cred = current_cred();
559 int rc = 0, i;
560 struct superblock_security_struct *sbsec = sb->s_security;
561 const char *name = sb->s_type->name;
562 struct inode *inode = sbsec->sb->s_root->d_inode;
563 struct inode_security_struct *root_isec = inode->i_security;
564 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
565 u32 defcontext_sid = 0;
566 char **mount_options = opts->mnt_opts;
567 int *flags = opts->mnt_opts_flags;
568 int num_opts = opts->num_mnt_opts;
569
570 mutex_lock(&sbsec->lock);
571
572 if (!ss_initialized) {
573 if (!num_opts) {
574 /* Defer initialization until selinux_complete_init,
575 after the initial policy is loaded and the security
576 server is ready to handle calls. */
577 goto out;
578 }
579 rc = -EINVAL;
580 printk(KERN_WARNING "SELinux: Unable to set superblock options "
581 "before the security server is initialized\n");
582 goto out;
583 }
584
585 /*
586 * Binary mount data FS will come through this function twice. Once
587 * from an explicit call and once from the generic calls from the vfs.
588 * Since the generic VFS calls will not contain any security mount data
589 * we need to skip the double mount verification.
590 *
591 * This does open a hole in which we will not notice if the first
592 * mount using this sb set explict options and a second mount using
593 * this sb does not set any security options. (The first options
594 * will be used for both mounts)
595 */
596 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
597 && (num_opts == 0))
598 goto out;
599
600 /*
601 * parse the mount options, check if they are valid sids.
602 * also check if someone is trying to mount the same sb more
603 * than once with different security options.
604 */
605 for (i = 0; i < num_opts; i++) {
606 u32 sid;
607
608 if (flags[i] == SE_SBLABELSUPP)
609 continue;
610 rc = security_context_to_sid(mount_options[i],
611 strlen(mount_options[i]), &sid);
612 if (rc) {
613 printk(KERN_WARNING "SELinux: security_context_to_sid"
614 "(%s) failed for (dev %s, type %s) errno=%d\n",
615 mount_options[i], sb->s_id, name, rc);
616 goto out;
617 }
618 switch (flags[i]) {
619 case FSCONTEXT_MNT:
620 fscontext_sid = sid;
621
622 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
623 fscontext_sid))
624 goto out_double_mount;
625
626 sbsec->flags |= FSCONTEXT_MNT;
627 break;
628 case CONTEXT_MNT:
629 context_sid = sid;
630
631 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
632 context_sid))
633 goto out_double_mount;
634
635 sbsec->flags |= CONTEXT_MNT;
636 break;
637 case ROOTCONTEXT_MNT:
638 rootcontext_sid = sid;
639
640 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
641 rootcontext_sid))
642 goto out_double_mount;
643
644 sbsec->flags |= ROOTCONTEXT_MNT;
645
646 break;
647 case DEFCONTEXT_MNT:
648 defcontext_sid = sid;
649
650 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
651 defcontext_sid))
652 goto out_double_mount;
653
654 sbsec->flags |= DEFCONTEXT_MNT;
655
656 break;
657 default:
658 rc = -EINVAL;
659 goto out;
660 }
661 }
662
663 if (sbsec->flags & SE_SBINITIALIZED) {
664 /* previously mounted with options, but not on this attempt? */
665 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
666 goto out_double_mount;
667 rc = 0;
668 goto out;
669 }
670
671 if (strcmp(sb->s_type->name, "proc") == 0)
672 sbsec->flags |= SE_SBPROC;
673
674 /* Determine the labeling behavior to use for this filesystem type. */
675 rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
676 if (rc) {
677 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
678 __func__, sb->s_type->name, rc);
679 goto out;
680 }
681
682 /* sets the context of the superblock for the fs being mounted. */
683 if (fscontext_sid) {
684 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
685 if (rc)
686 goto out;
687
688 sbsec->sid = fscontext_sid;
689 }
690
691 /*
692 * Switch to using mount point labeling behavior.
693 * sets the label used on all file below the mountpoint, and will set
694 * the superblock context if not already set.
695 */
696 if (context_sid) {
697 if (!fscontext_sid) {
698 rc = may_context_mount_sb_relabel(context_sid, sbsec,
699 cred);
700 if (rc)
701 goto out;
702 sbsec->sid = context_sid;
703 } else {
704 rc = may_context_mount_inode_relabel(context_sid, sbsec,
705 cred);
706 if (rc)
707 goto out;
708 }
709 if (!rootcontext_sid)
710 rootcontext_sid = context_sid;
711
712 sbsec->mntpoint_sid = context_sid;
713 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
714 }
715
716 if (rootcontext_sid) {
717 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
718 cred);
719 if (rc)
720 goto out;
721
722 root_isec->sid = rootcontext_sid;
723 root_isec->initialized = 1;
724 }
725
726 if (defcontext_sid) {
727 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
728 rc = -EINVAL;
729 printk(KERN_WARNING "SELinux: defcontext option is "
730 "invalid for this filesystem type\n");
731 goto out;
732 }
733
734 if (defcontext_sid != sbsec->def_sid) {
735 rc = may_context_mount_inode_relabel(defcontext_sid,
736 sbsec, cred);
737 if (rc)
738 goto out;
739 }
740
741 sbsec->def_sid = defcontext_sid;
742 }
743
744 rc = sb_finish_set_opts(sb);
745out:
746 mutex_unlock(&sbsec->lock);
747 return rc;
748out_double_mount:
749 rc = -EINVAL;
750 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
751 "security settings for (dev %s, type %s)\n", sb->s_id, name);
752 goto out;
753}
754
755static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
756 struct super_block *newsb)
757{
758 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
759 struct superblock_security_struct *newsbsec = newsb->s_security;
760
761 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
762 int set_context = (oldsbsec->flags & CONTEXT_MNT);
763 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
764
765 /*
766 * if the parent was able to be mounted it clearly had no special lsm
767 * mount options. thus we can safely deal with this superblock later
768 */
769 if (!ss_initialized)
770 return;
771
772 /* how can we clone if the old one wasn't set up?? */
773 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
774
775 /* if fs is reusing a sb, just let its options stand... */
776 if (newsbsec->flags & SE_SBINITIALIZED)
777 return;
778
779 mutex_lock(&newsbsec->lock);
780
781 newsbsec->flags = oldsbsec->flags;
782
783 newsbsec->sid = oldsbsec->sid;
784 newsbsec->def_sid = oldsbsec->def_sid;
785 newsbsec->behavior = oldsbsec->behavior;
786
787 if (set_context) {
788 u32 sid = oldsbsec->mntpoint_sid;
789
790 if (!set_fscontext)
791 newsbsec->sid = sid;
792 if (!set_rootcontext) {
793 struct inode *newinode = newsb->s_root->d_inode;
794 struct inode_security_struct *newisec = newinode->i_security;
795 newisec->sid = sid;
796 }
797 newsbsec->mntpoint_sid = sid;
798 }
799 if (set_rootcontext) {
800 const struct inode *oldinode = oldsb->s_root->d_inode;
801 const struct inode_security_struct *oldisec = oldinode->i_security;
802 struct inode *newinode = newsb->s_root->d_inode;
803 struct inode_security_struct *newisec = newinode->i_security;
804
805 newisec->sid = oldisec->sid;
806 }
807
808 sb_finish_set_opts(newsb);
809 mutex_unlock(&newsbsec->lock);
810}
811
812static int selinux_parse_opts_str(char *options,
813 struct security_mnt_opts *opts)
814{
815 char *p;
816 char *context = NULL, *defcontext = NULL;
817 char *fscontext = NULL, *rootcontext = NULL;
818 int rc, num_mnt_opts = 0;
819
820 opts->num_mnt_opts = 0;
821
822 /* Standard string-based options. */
823 while ((p = strsep(&options, "|")) != NULL) {
824 int token;
825 substring_t args[MAX_OPT_ARGS];
826
827 if (!*p)
828 continue;
829
830 token = match_token(p, tokens, args);
831
832 switch (token) {
833 case Opt_context:
834 if (context || defcontext) {
835 rc = -EINVAL;
836 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
837 goto out_err;
838 }
839 context = match_strdup(&args[0]);
840 if (!context) {
841 rc = -ENOMEM;
842 goto out_err;
843 }
844 break;
845
846 case Opt_fscontext:
847 if (fscontext) {
848 rc = -EINVAL;
849 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
850 goto out_err;
851 }
852 fscontext = match_strdup(&args[0]);
853 if (!fscontext) {
854 rc = -ENOMEM;
855 goto out_err;
856 }
857 break;
858
859 case Opt_rootcontext:
860 if (rootcontext) {
861 rc = -EINVAL;
862 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
863 goto out_err;
864 }
865 rootcontext = match_strdup(&args[0]);
866 if (!rootcontext) {
867 rc = -ENOMEM;
868 goto out_err;
869 }
870 break;
871
872 case Opt_defcontext:
873 if (context || defcontext) {
874 rc = -EINVAL;
875 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
876 goto out_err;
877 }
878 defcontext = match_strdup(&args[0]);
879 if (!defcontext) {
880 rc = -ENOMEM;
881 goto out_err;
882 }
883 break;
884 case Opt_labelsupport:
885 break;
886 default:
887 rc = -EINVAL;
888 printk(KERN_WARNING "SELinux: unknown mount option\n");
889 goto out_err;
890
891 }
892 }
893
894 rc = -ENOMEM;
895 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
896 if (!opts->mnt_opts)
897 goto out_err;
898
899 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
900 if (!opts->mnt_opts_flags) {
901 kfree(opts->mnt_opts);
902 goto out_err;
903 }
904
905 if (fscontext) {
906 opts->mnt_opts[num_mnt_opts] = fscontext;
907 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
908 }
909 if (context) {
910 opts->mnt_opts[num_mnt_opts] = context;
911 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
912 }
913 if (rootcontext) {
914 opts->mnt_opts[num_mnt_opts] = rootcontext;
915 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
916 }
917 if (defcontext) {
918 opts->mnt_opts[num_mnt_opts] = defcontext;
919 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
920 }
921
922 opts->num_mnt_opts = num_mnt_opts;
923 return 0;
924
925out_err:
926 kfree(context);
927 kfree(defcontext);
928 kfree(fscontext);
929 kfree(rootcontext);
930 return rc;
931}
932/*
933 * string mount options parsing and call set the sbsec
934 */
935static int superblock_doinit(struct super_block *sb, void *data)
936{
937 int rc = 0;
938 char *options = data;
939 struct security_mnt_opts opts;
940
941 security_init_mnt_opts(&opts);
942
943 if (!data)
944 goto out;
945
946 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
947
948 rc = selinux_parse_opts_str(options, &opts);
949 if (rc)
950 goto out_err;
951
952out:
953 rc = selinux_set_mnt_opts(sb, &opts);
954
955out_err:
956 security_free_mnt_opts(&opts);
957 return rc;
958}
959
960static void selinux_write_opts(struct seq_file *m,
961 struct security_mnt_opts *opts)
962{
963 int i;
964 char *prefix;
965
966 for (i = 0; i < opts->num_mnt_opts; i++) {
967 char *has_comma;
968
969 if (opts->mnt_opts[i])
970 has_comma = strchr(opts->mnt_opts[i], ',');
971 else
972 has_comma = NULL;
973
974 switch (opts->mnt_opts_flags[i]) {
975 case CONTEXT_MNT:
976 prefix = CONTEXT_STR;
977 break;
978 case FSCONTEXT_MNT:
979 prefix = FSCONTEXT_STR;
980 break;
981 case ROOTCONTEXT_MNT:
982 prefix = ROOTCONTEXT_STR;
983 break;
984 case DEFCONTEXT_MNT:
985 prefix = DEFCONTEXT_STR;
986 break;
987 case SE_SBLABELSUPP:
988 seq_putc(m, ',');
989 seq_puts(m, LABELSUPP_STR);
990 continue;
991 default:
992 BUG();
993 return;
994 };
995 /* we need a comma before each option */
996 seq_putc(m, ',');
997 seq_puts(m, prefix);
998 if (has_comma)
999 seq_putc(m, '\"');
1000 seq_puts(m, opts->mnt_opts[i]);
1001 if (has_comma)
1002 seq_putc(m, '\"');
1003 }
1004}
1005
1006static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007{
1008 struct security_mnt_opts opts;
1009 int rc;
1010
1011 rc = selinux_get_mnt_opts(sb, &opts);
1012 if (rc) {
1013 /* before policy load we may get EINVAL, don't show anything */
1014 if (rc == -EINVAL)
1015 rc = 0;
1016 return rc;
1017 }
1018
1019 selinux_write_opts(m, &opts);
1020
1021 security_free_mnt_opts(&opts);
1022
1023 return rc;
1024}
1025
1026static inline u16 inode_mode_to_security_class(umode_t mode)
1027{
1028 switch (mode & S_IFMT) {
1029 case S_IFSOCK:
1030 return SECCLASS_SOCK_FILE;
1031 case S_IFLNK:
1032 return SECCLASS_LNK_FILE;
1033 case S_IFREG:
1034 return SECCLASS_FILE;
1035 case S_IFBLK:
1036 return SECCLASS_BLK_FILE;
1037 case S_IFDIR:
1038 return SECCLASS_DIR;
1039 case S_IFCHR:
1040 return SECCLASS_CHR_FILE;
1041 case S_IFIFO:
1042 return SECCLASS_FIFO_FILE;
1043
1044 }
1045
1046 return SECCLASS_FILE;
1047}
1048
1049static inline int default_protocol_stream(int protocol)
1050{
1051 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052}
1053
1054static inline int default_protocol_dgram(int protocol)
1055{
1056 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057}
1058
1059static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060{
1061 switch (family) {
1062 case PF_UNIX:
1063 switch (type) {
1064 case SOCK_STREAM:
1065 case SOCK_SEQPACKET:
1066 return SECCLASS_UNIX_STREAM_SOCKET;
1067 case SOCK_DGRAM:
1068 return SECCLASS_UNIX_DGRAM_SOCKET;
1069 }
1070 break;
1071 case PF_INET:
1072 case PF_INET6:
1073 switch (type) {
1074 case SOCK_STREAM:
1075 if (default_protocol_stream(protocol))
1076 return SECCLASS_TCP_SOCKET;
1077 else
1078 return SECCLASS_RAWIP_SOCKET;
1079 case SOCK_DGRAM:
1080 if (default_protocol_dgram(protocol))
1081 return SECCLASS_UDP_SOCKET;
1082 else
1083 return SECCLASS_RAWIP_SOCKET;
1084 case SOCK_DCCP:
1085 return SECCLASS_DCCP_SOCKET;
1086 default:
1087 return SECCLASS_RAWIP_SOCKET;
1088 }
1089 break;
1090 case PF_NETLINK:
1091 switch (protocol) {
1092 case NETLINK_ROUTE:
1093 return SECCLASS_NETLINK_ROUTE_SOCKET;
1094 case NETLINK_FIREWALL:
1095 return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096 case NETLINK_INET_DIAG:
1097 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098 case NETLINK_NFLOG:
1099 return SECCLASS_NETLINK_NFLOG_SOCKET;
1100 case NETLINK_XFRM:
1101 return SECCLASS_NETLINK_XFRM_SOCKET;
1102 case NETLINK_SELINUX:
1103 return SECCLASS_NETLINK_SELINUX_SOCKET;
1104 case NETLINK_AUDIT:
1105 return SECCLASS_NETLINK_AUDIT_SOCKET;
1106 case NETLINK_IP6_FW:
1107 return SECCLASS_NETLINK_IP6FW_SOCKET;
1108 case NETLINK_DNRTMSG:
1109 return SECCLASS_NETLINK_DNRT_SOCKET;
1110 case NETLINK_KOBJECT_UEVENT:
1111 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112 default:
1113 return SECCLASS_NETLINK_SOCKET;
1114 }
1115 case PF_PACKET:
1116 return SECCLASS_PACKET_SOCKET;
1117 case PF_KEY:
1118 return SECCLASS_KEY_SOCKET;
1119 case PF_APPLETALK:
1120 return SECCLASS_APPLETALK_SOCKET;
1121 }
1122
1123 return SECCLASS_SOCKET;
1124}
1125
1126#ifdef CONFIG_PROC_FS
1127static int selinux_proc_get_sid(struct dentry *dentry,
1128 u16 tclass,
1129 u32 *sid)
1130{
1131 int rc;
1132 char *buffer, *path;
1133
1134 buffer = (char *)__get_free_page(GFP_KERNEL);
1135 if (!buffer)
1136 return -ENOMEM;
1137
1138 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139 if (IS_ERR(path))
1140 rc = PTR_ERR(path);
1141 else {
1142 /* each process gets a /proc/PID/ entry. Strip off the
1143 * PID part to get a valid selinux labeling.
1144 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145 while (path[1] >= '0' && path[1] <= '9') {
1146 path[1] = '/';
1147 path++;
1148 }
1149 rc = security_genfs_sid("proc", path, tclass, sid);
1150 }
1151 free_page((unsigned long)buffer);
1152 return rc;
1153}
1154#else
1155static int selinux_proc_get_sid(struct dentry *dentry,
1156 u16 tclass,
1157 u32 *sid)
1158{
1159 return -EINVAL;
1160}
1161#endif
1162
1163/* The inode's security attributes must be initialized before first use. */
1164static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165{
1166 struct superblock_security_struct *sbsec = NULL;
1167 struct inode_security_struct *isec = inode->i_security;
1168 u32 sid;
1169 struct dentry *dentry;
1170#define INITCONTEXTLEN 255
1171 char *context = NULL;
1172 unsigned len = 0;
1173 int rc = 0;
1174
1175 if (isec->initialized)
1176 goto out;
1177
1178 mutex_lock(&isec->lock);
1179 if (isec->initialized)
1180 goto out_unlock;
1181
1182 sbsec = inode->i_sb->s_security;
1183 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184 /* Defer initialization until selinux_complete_init,
1185 after the initial policy is loaded and the security
1186 server is ready to handle calls. */
1187 spin_lock(&sbsec->isec_lock);
1188 if (list_empty(&isec->list))
1189 list_add(&isec->list, &sbsec->isec_head);
1190 spin_unlock(&sbsec->isec_lock);
1191 goto out_unlock;
1192 }
1193
1194 switch (sbsec->behavior) {
1195 case SECURITY_FS_USE_XATTR:
1196 if (!inode->i_op->getxattr) {
1197 isec->sid = sbsec->def_sid;
1198 break;
1199 }
1200
1201 /* Need a dentry, since the xattr API requires one.
1202 Life would be simpler if we could just pass the inode. */
1203 if (opt_dentry) {
1204 /* Called from d_instantiate or d_splice_alias. */
1205 dentry = dget(opt_dentry);
1206 } else {
1207 /* Called from selinux_complete_init, try to find a dentry. */
1208 dentry = d_find_alias(inode);
1209 }
1210 if (!dentry) {
1211 /*
1212 * this is can be hit on boot when a file is accessed
1213 * before the policy is loaded. When we load policy we
1214 * may find inodes that have no dentry on the
1215 * sbsec->isec_head list. No reason to complain as these
1216 * will get fixed up the next time we go through
1217 * inode_doinit with a dentry, before these inodes could
1218 * be used again by userspace.
1219 */
1220 goto out_unlock;
1221 }
1222
1223 len = INITCONTEXTLEN;
1224 context = kmalloc(len+1, GFP_NOFS);
1225 if (!context) {
1226 rc = -ENOMEM;
1227 dput(dentry);
1228 goto out_unlock;
1229 }
1230 context[len] = '\0';
1231 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232 context, len);
1233 if (rc == -ERANGE) {
1234 kfree(context);
1235
1236 /* Need a larger buffer. Query for the right size. */
1237 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238 NULL, 0);
1239 if (rc < 0) {
1240 dput(dentry);
1241 goto out_unlock;
1242 }
1243 len = rc;
1244 context = kmalloc(len+1, GFP_NOFS);
1245 if (!context) {
1246 rc = -ENOMEM;
1247 dput(dentry);
1248 goto out_unlock;
1249 }
1250 context[len] = '\0';
1251 rc = inode->i_op->getxattr(dentry,
1252 XATTR_NAME_SELINUX,
1253 context, len);
1254 }
1255 dput(dentry);
1256 if (rc < 0) {
1257 if (rc != -ENODATA) {
1258 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1259 "%d for dev=%s ino=%ld\n", __func__,
1260 -rc, inode->i_sb->s_id, inode->i_ino);
1261 kfree(context);
1262 goto out_unlock;
1263 }
1264 /* Map ENODATA to the default file SID */
1265 sid = sbsec->def_sid;
1266 rc = 0;
1267 } else {
1268 rc = security_context_to_sid_default(context, rc, &sid,
1269 sbsec->def_sid,
1270 GFP_NOFS);
1271 if (rc) {
1272 char *dev = inode->i_sb->s_id;
1273 unsigned long ino = inode->i_ino;
1274
1275 if (rc == -EINVAL) {
1276 if (printk_ratelimit())
1277 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278 "context=%s. This indicates you may need to relabel the inode or the "
1279 "filesystem in question.\n", ino, dev, context);
1280 } else {
1281 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1282 "returned %d for dev=%s ino=%ld\n",
1283 __func__, context, -rc, dev, ino);
1284 }
1285 kfree(context);
1286 /* Leave with the unlabeled SID */
1287 rc = 0;
1288 break;
1289 }
1290 }
1291 kfree(context);
1292 isec->sid = sid;
1293 break;
1294 case SECURITY_FS_USE_TASK:
1295 isec->sid = isec->task_sid;
1296 break;
1297 case SECURITY_FS_USE_TRANS:
1298 /* Default to the fs SID. */
1299 isec->sid = sbsec->sid;
1300
1301 /* Try to obtain a transition SID. */
1302 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304 isec->sclass, NULL, &sid);
1305 if (rc)
1306 goto out_unlock;
1307 isec->sid = sid;
1308 break;
1309 case SECURITY_FS_USE_MNTPOINT:
1310 isec->sid = sbsec->mntpoint_sid;
1311 break;
1312 default:
1313 /* Default to the fs superblock SID. */
1314 isec->sid = sbsec->sid;
1315
1316 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317 if (opt_dentry) {
1318 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319 rc = selinux_proc_get_sid(opt_dentry,
1320 isec->sclass,
1321 &sid);
1322 if (rc)
1323 goto out_unlock;
1324 isec->sid = sid;
1325 }
1326 }
1327 break;
1328 }
1329
1330 isec->initialized = 1;
1331
1332out_unlock:
1333 mutex_unlock(&isec->lock);
1334out:
1335 if (isec->sclass == SECCLASS_FILE)
1336 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337 return rc;
1338}
1339
1340/* Convert a Linux signal to an access vector. */
1341static inline u32 signal_to_av(int sig)
1342{
1343 u32 perm = 0;
1344
1345 switch (sig) {
1346 case SIGCHLD:
1347 /* Commonly granted from child to parent. */
1348 perm = PROCESS__SIGCHLD;
1349 break;
1350 case SIGKILL:
1351 /* Cannot be caught or ignored */
1352 perm = PROCESS__SIGKILL;
1353 break;
1354 case SIGSTOP:
1355 /* Cannot be caught or ignored */
1356 perm = PROCESS__SIGSTOP;
1357 break;
1358 default:
1359 /* All other signals. */
1360 perm = PROCESS__SIGNAL;
1361 break;
1362 }
1363
1364 return perm;
1365}
1366
1367/*
1368 * Check permission between a pair of credentials
1369 * fork check, ptrace check, etc.
1370 */
1371static int cred_has_perm(const struct cred *actor,
1372 const struct cred *target,
1373 u32 perms)
1374{
1375 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378}
1379
1380/*
1381 * Check permission between a pair of tasks, e.g. signal checks,
1382 * fork check, ptrace check, etc.
1383 * tsk1 is the actor and tsk2 is the target
1384 * - this uses the default subjective creds of tsk1
1385 */
1386static int task_has_perm(const struct task_struct *tsk1,
1387 const struct task_struct *tsk2,
1388 u32 perms)
1389{
1390 const struct task_security_struct *__tsec1, *__tsec2;
1391 u32 sid1, sid2;
1392
1393 rcu_read_lock();
1394 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1395 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1396 rcu_read_unlock();
1397 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398}
1399
1400/*
1401 * Check permission between current and another task, e.g. signal checks,
1402 * fork check, ptrace check, etc.
1403 * current is the actor and tsk2 is the target
1404 * - this uses current's subjective creds
1405 */
1406static int current_has_perm(const struct task_struct *tsk,
1407 u32 perms)
1408{
1409 u32 sid, tsid;
1410
1411 sid = current_sid();
1412 tsid = task_sid(tsk);
1413 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414}
1415
1416#if CAP_LAST_CAP > 63
1417#error Fix SELinux to handle capabilities > 63.
1418#endif
1419
1420/* Check whether a task is allowed to use a capability. */
1421static int task_has_capability(struct task_struct *tsk,
1422 const struct cred *cred,
1423 int cap, int audit)
1424{
1425 struct common_audit_data ad;
1426 struct av_decision avd;
1427 u16 sclass;
1428 u32 sid = cred_sid(cred);
1429 u32 av = CAP_TO_MASK(cap);
1430 int rc;
1431
1432 COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433 ad.tsk = tsk;
1434 ad.u.cap = cap;
1435
1436 switch (CAP_TO_INDEX(cap)) {
1437 case 0:
1438 sclass = SECCLASS_CAPABILITY;
1439 break;
1440 case 1:
1441 sclass = SECCLASS_CAPABILITY2;
1442 break;
1443 default:
1444 printk(KERN_ERR
1445 "SELinux: out of range capability %d\n", cap);
1446 BUG();
1447 return -EINVAL;
1448 }
1449
1450 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451 if (audit == SECURITY_CAP_AUDIT) {
1452 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453 if (rc2)
1454 return rc2;
1455 }
1456 return rc;
1457}
1458
1459/* Check whether a task is allowed to use a system operation. */
1460static int task_has_system(struct task_struct *tsk,
1461 u32 perms)
1462{
1463 u32 sid = task_sid(tsk);
1464
1465 return avc_has_perm(sid, SECINITSID_KERNEL,
1466 SECCLASS_SYSTEM, perms, NULL);
1467}
1468
1469/* Check whether a task has a particular permission to an inode.
1470 The 'adp' parameter is optional and allows other audit
1471 data to be passed (e.g. the dentry). */
1472static int inode_has_perm(const struct cred *cred,
1473 struct inode *inode,
1474 u32 perms,
1475 struct common_audit_data *adp,
1476 unsigned flags)
1477{
1478 struct inode_security_struct *isec;
1479 u32 sid;
1480
1481 validate_creds(cred);
1482
1483 if (unlikely(IS_PRIVATE(inode)))
1484 return 0;
1485
1486 sid = cred_sid(cred);
1487 isec = inode->i_security;
1488
1489 return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1490}
1491
1492static int inode_has_perm_noadp(const struct cred *cred,
1493 struct inode *inode,
1494 u32 perms,
1495 unsigned flags)
1496{
1497 struct common_audit_data ad;
1498
1499 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1500 ad.u.inode = inode;
1501 return inode_has_perm(cred, inode, perms, &ad, flags);
1502}
1503
1504/* Same as inode_has_perm, but pass explicit audit data containing
1505 the dentry to help the auditing code to more easily generate the
1506 pathname if needed. */
1507static inline int dentry_has_perm(const struct cred *cred,
1508 struct dentry *dentry,
1509 u32 av)
1510{
1511 struct inode *inode = dentry->d_inode;
1512 struct common_audit_data ad;
1513
1514 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1515 ad.u.dentry = dentry;
1516 return inode_has_perm(cred, inode, av, &ad, 0);
1517}
1518
1519/* Same as inode_has_perm, but pass explicit audit data containing
1520 the path to help the auditing code to more easily generate the
1521 pathname if needed. */
1522static inline int path_has_perm(const struct cred *cred,
1523 struct path *path,
1524 u32 av)
1525{
1526 struct inode *inode = path->dentry->d_inode;
1527 struct common_audit_data ad;
1528
1529 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1530 ad.u.path = *path;
1531 return inode_has_perm(cred, inode, av, &ad, 0);
1532}
1533
1534/* Check whether a task can use an open file descriptor to
1535 access an inode in a given way. Check access to the
1536 descriptor itself, and then use dentry_has_perm to
1537 check a particular permission to the file.
1538 Access to the descriptor is implicitly granted if it
1539 has the same SID as the process. If av is zero, then
1540 access to the file is not checked, e.g. for cases
1541 where only the descriptor is affected like seek. */
1542static int file_has_perm(const struct cred *cred,
1543 struct file *file,
1544 u32 av)
1545{
1546 struct file_security_struct *fsec = file->f_security;
1547 struct inode *inode = file->f_path.dentry->d_inode;
1548 struct common_audit_data ad;
1549 u32 sid = cred_sid(cred);
1550 int rc;
1551
1552 COMMON_AUDIT_DATA_INIT(&ad, PATH);
1553 ad.u.path = file->f_path;
1554
1555 if (sid != fsec->sid) {
1556 rc = avc_has_perm(sid, fsec->sid,
1557 SECCLASS_FD,
1558 FD__USE,
1559 &ad);
1560 if (rc)
1561 goto out;
1562 }
1563
1564 /* av is zero if only checking access to the descriptor. */
1565 rc = 0;
1566 if (av)
1567 rc = inode_has_perm(cred, inode, av, &ad, 0);
1568
1569out:
1570 return rc;
1571}
1572
1573/* Check whether a task can create a file. */
1574static int may_create(struct inode *dir,
1575 struct dentry *dentry,
1576 u16 tclass)
1577{
1578 const struct task_security_struct *tsec = current_security();
1579 struct inode_security_struct *dsec;
1580 struct superblock_security_struct *sbsec;
1581 u32 sid, newsid;
1582 struct common_audit_data ad;
1583 int rc;
1584
1585 dsec = dir->i_security;
1586 sbsec = dir->i_sb->s_security;
1587
1588 sid = tsec->sid;
1589 newsid = tsec->create_sid;
1590
1591 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1592 ad.u.dentry = dentry;
1593
1594 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1595 DIR__ADD_NAME | DIR__SEARCH,
1596 &ad);
1597 if (rc)
1598 return rc;
1599
1600 if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1601 rc = security_transition_sid(sid, dsec->sid, tclass,
1602 &dentry->d_name, &newsid);
1603 if (rc)
1604 return rc;
1605 }
1606
1607 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1608 if (rc)
1609 return rc;
1610
1611 return avc_has_perm(newsid, sbsec->sid,
1612 SECCLASS_FILESYSTEM,
1613 FILESYSTEM__ASSOCIATE, &ad);
1614}
1615
1616/* Check whether a task can create a key. */
1617static int may_create_key(u32 ksid,
1618 struct task_struct *ctx)
1619{
1620 u32 sid = task_sid(ctx);
1621
1622 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1623}
1624
1625#define MAY_LINK 0
1626#define MAY_UNLINK 1
1627#define MAY_RMDIR 2
1628
1629/* Check whether a task can link, unlink, or rmdir a file/directory. */
1630static int may_link(struct inode *dir,
1631 struct dentry *dentry,
1632 int kind)
1633
1634{
1635 struct inode_security_struct *dsec, *isec;
1636 struct common_audit_data ad;
1637 u32 sid = current_sid();
1638 u32 av;
1639 int rc;
1640
1641 dsec = dir->i_security;
1642 isec = dentry->d_inode->i_security;
1643
1644 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1645 ad.u.dentry = dentry;
1646
1647 av = DIR__SEARCH;
1648 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1649 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1650 if (rc)
1651 return rc;
1652
1653 switch (kind) {
1654 case MAY_LINK:
1655 av = FILE__LINK;
1656 break;
1657 case MAY_UNLINK:
1658 av = FILE__UNLINK;
1659 break;
1660 case MAY_RMDIR:
1661 av = DIR__RMDIR;
1662 break;
1663 default:
1664 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1665 __func__, kind);
1666 return 0;
1667 }
1668
1669 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1670 return rc;
1671}
1672
1673static inline int may_rename(struct inode *old_dir,
1674 struct dentry *old_dentry,
1675 struct inode *new_dir,
1676 struct dentry *new_dentry)
1677{
1678 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1679 struct common_audit_data ad;
1680 u32 sid = current_sid();
1681 u32 av;
1682 int old_is_dir, new_is_dir;
1683 int rc;
1684
1685 old_dsec = old_dir->i_security;
1686 old_isec = old_dentry->d_inode->i_security;
1687 old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1688 new_dsec = new_dir->i_security;
1689
1690 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1691
1692 ad.u.dentry = old_dentry;
1693 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1694 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1695 if (rc)
1696 return rc;
1697 rc = avc_has_perm(sid, old_isec->sid,
1698 old_isec->sclass, FILE__RENAME, &ad);
1699 if (rc)
1700 return rc;
1701 if (old_is_dir && new_dir != old_dir) {
1702 rc = avc_has_perm(sid, old_isec->sid,
1703 old_isec->sclass, DIR__REPARENT, &ad);
1704 if (rc)
1705 return rc;
1706 }
1707
1708 ad.u.dentry = new_dentry;
1709 av = DIR__ADD_NAME | DIR__SEARCH;
1710 if (new_dentry->d_inode)
1711 av |= DIR__REMOVE_NAME;
1712 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1713 if (rc)
1714 return rc;
1715 if (new_dentry->d_inode) {
1716 new_isec = new_dentry->d_inode->i_security;
1717 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1718 rc = avc_has_perm(sid, new_isec->sid,
1719 new_isec->sclass,
1720 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1721 if (rc)
1722 return rc;
1723 }
1724
1725 return 0;
1726}
1727
1728/* Check whether a task can perform a filesystem operation. */
1729static int superblock_has_perm(const struct cred *cred,
1730 struct super_block *sb,
1731 u32 perms,
1732 struct common_audit_data *ad)
1733{
1734 struct superblock_security_struct *sbsec;
1735 u32 sid = cred_sid(cred);
1736
1737 sbsec = sb->s_security;
1738 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1739}
1740
1741/* Convert a Linux mode and permission mask to an access vector. */
1742static inline u32 file_mask_to_av(int mode, int mask)
1743{
1744 u32 av = 0;
1745
1746 if ((mode & S_IFMT) != S_IFDIR) {
1747 if (mask & MAY_EXEC)
1748 av |= FILE__EXECUTE;
1749 if (mask & MAY_READ)
1750 av |= FILE__READ;
1751
1752 if (mask & MAY_APPEND)
1753 av |= FILE__APPEND;
1754 else if (mask & MAY_WRITE)
1755 av |= FILE__WRITE;
1756
1757 } else {
1758 if (mask & MAY_EXEC)
1759 av |= DIR__SEARCH;
1760 if (mask & MAY_WRITE)
1761 av |= DIR__WRITE;
1762 if (mask & MAY_READ)
1763 av |= DIR__READ;
1764 }
1765
1766 return av;
1767}
1768
1769/* Convert a Linux file to an access vector. */
1770static inline u32 file_to_av(struct file *file)
1771{
1772 u32 av = 0;
1773
1774 if (file->f_mode & FMODE_READ)
1775 av |= FILE__READ;
1776 if (file->f_mode & FMODE_WRITE) {
1777 if (file->f_flags & O_APPEND)
1778 av |= FILE__APPEND;
1779 else
1780 av |= FILE__WRITE;
1781 }
1782 if (!av) {
1783 /*
1784 * Special file opened with flags 3 for ioctl-only use.
1785 */
1786 av = FILE__IOCTL;
1787 }
1788
1789 return av;
1790}
1791
1792/*
1793 * Convert a file to an access vector and include the correct open
1794 * open permission.
1795 */
1796static inline u32 open_file_to_av(struct file *file)
1797{
1798 u32 av = file_to_av(file);
1799
1800 if (selinux_policycap_openperm)
1801 av |= FILE__OPEN;
1802
1803 return av;
1804}
1805
1806/* Hook functions begin here. */
1807
1808static int selinux_ptrace_access_check(struct task_struct *child,
1809 unsigned int mode)
1810{
1811 int rc;
1812
1813 rc = cap_ptrace_access_check(child, mode);
1814 if (rc)
1815 return rc;
1816
1817 if (mode == PTRACE_MODE_READ) {
1818 u32 sid = current_sid();
1819 u32 csid = task_sid(child);
1820 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1821 }
1822
1823 return current_has_perm(child, PROCESS__PTRACE);
1824}
1825
1826static int selinux_ptrace_traceme(struct task_struct *parent)
1827{
1828 int rc;
1829
1830 rc = cap_ptrace_traceme(parent);
1831 if (rc)
1832 return rc;
1833
1834 return task_has_perm(parent, current, PROCESS__PTRACE);
1835}
1836
1837static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1838 kernel_cap_t *inheritable, kernel_cap_t *permitted)
1839{
1840 int error;
1841
1842 error = current_has_perm(target, PROCESS__GETCAP);
1843 if (error)
1844 return error;
1845
1846 return cap_capget(target, effective, inheritable, permitted);
1847}
1848
1849static int selinux_capset(struct cred *new, const struct cred *old,
1850 const kernel_cap_t *effective,
1851 const kernel_cap_t *inheritable,
1852 const kernel_cap_t *permitted)
1853{
1854 int error;
1855
1856 error = cap_capset(new, old,
1857 effective, inheritable, permitted);
1858 if (error)
1859 return error;
1860
1861 return cred_has_perm(old, new, PROCESS__SETCAP);
1862}
1863
1864/*
1865 * (This comment used to live with the selinux_task_setuid hook,
1866 * which was removed).
1867 *
1868 * Since setuid only affects the current process, and since the SELinux
1869 * controls are not based on the Linux identity attributes, SELinux does not
1870 * need to control this operation. However, SELinux does control the use of
1871 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1872 */
1873
1874static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1875 struct user_namespace *ns, int cap, int audit)
1876{
1877 int rc;
1878
1879 rc = cap_capable(tsk, cred, ns, cap, audit);
1880 if (rc)
1881 return rc;
1882
1883 return task_has_capability(tsk, cred, cap, audit);
1884}
1885
1886static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1887{
1888 const struct cred *cred = current_cred();
1889 int rc = 0;
1890
1891 if (!sb)
1892 return 0;
1893
1894 switch (cmds) {
1895 case Q_SYNC:
1896 case Q_QUOTAON:
1897 case Q_QUOTAOFF:
1898 case Q_SETINFO:
1899 case Q_SETQUOTA:
1900 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1901 break;
1902 case Q_GETFMT:
1903 case Q_GETINFO:
1904 case Q_GETQUOTA:
1905 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1906 break;
1907 default:
1908 rc = 0; /* let the kernel handle invalid cmds */
1909 break;
1910 }
1911 return rc;
1912}
1913
1914static int selinux_quota_on(struct dentry *dentry)
1915{
1916 const struct cred *cred = current_cred();
1917
1918 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1919}
1920
1921static int selinux_syslog(int type)
1922{
1923 int rc;
1924
1925 switch (type) {
1926 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
1927 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1928 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1929 break;
1930 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1931 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
1932 /* Set level of messages printed to console */
1933 case SYSLOG_ACTION_CONSOLE_LEVEL:
1934 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1935 break;
1936 case SYSLOG_ACTION_CLOSE: /* Close log */
1937 case SYSLOG_ACTION_OPEN: /* Open log */
1938 case SYSLOG_ACTION_READ: /* Read from log */
1939 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
1940 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
1941 default:
1942 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1943 break;
1944 }
1945 return rc;
1946}
1947
1948/*
1949 * Check that a process has enough memory to allocate a new virtual
1950 * mapping. 0 means there is enough memory for the allocation to
1951 * succeed and -ENOMEM implies there is not.
1952 *
1953 * Do not audit the selinux permission check, as this is applied to all
1954 * processes that allocate mappings.
1955 */
1956static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1957{
1958 int rc, cap_sys_admin = 0;
1959
1960 rc = selinux_capable(current, current_cred(),
1961 &init_user_ns, CAP_SYS_ADMIN,
1962 SECURITY_CAP_NOAUDIT);
1963 if (rc == 0)
1964 cap_sys_admin = 1;
1965
1966 return __vm_enough_memory(mm, pages, cap_sys_admin);
1967}
1968
1969/* binprm security operations */
1970
1971static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1972{
1973 const struct task_security_struct *old_tsec;
1974 struct task_security_struct *new_tsec;
1975 struct inode_security_struct *isec;
1976 struct common_audit_data ad;
1977 struct inode *inode = bprm->file->f_path.dentry->d_inode;
1978 int rc;
1979
1980 rc = cap_bprm_set_creds(bprm);
1981 if (rc)
1982 return rc;
1983
1984 /* SELinux context only depends on initial program or script and not
1985 * the script interpreter */
1986 if (bprm->cred_prepared)
1987 return 0;
1988
1989 old_tsec = current_security();
1990 new_tsec = bprm->cred->security;
1991 isec = inode->i_security;
1992
1993 /* Default to the current task SID. */
1994 new_tsec->sid = old_tsec->sid;
1995 new_tsec->osid = old_tsec->sid;
1996
1997 /* Reset fs, key, and sock SIDs on execve. */
1998 new_tsec->create_sid = 0;
1999 new_tsec->keycreate_sid = 0;
2000 new_tsec->sockcreate_sid = 0;
2001
2002 if (old_tsec->exec_sid) {
2003 new_tsec->sid = old_tsec->exec_sid;
2004 /* Reset exec SID on execve. */
2005 new_tsec->exec_sid = 0;
2006 } else {
2007 /* Check for a default transition on this program. */
2008 rc = security_transition_sid(old_tsec->sid, isec->sid,
2009 SECCLASS_PROCESS, NULL,
2010 &new_tsec->sid);
2011 if (rc)
2012 return rc;
2013 }
2014
2015 COMMON_AUDIT_DATA_INIT(&ad, PATH);
2016 ad.u.path = bprm->file->f_path;
2017
2018 if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2019 new_tsec->sid = old_tsec->sid;
2020
2021 if (new_tsec->sid == old_tsec->sid) {
2022 rc = avc_has_perm(old_tsec->sid, isec->sid,
2023 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2024 if (rc)
2025 return rc;
2026 } else {
2027 /* Check permissions for the transition. */
2028 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2029 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2030 if (rc)
2031 return rc;
2032
2033 rc = avc_has_perm(new_tsec->sid, isec->sid,
2034 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2035 if (rc)
2036 return rc;
2037
2038 /* Check for shared state */
2039 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2040 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2041 SECCLASS_PROCESS, PROCESS__SHARE,
2042 NULL);
2043 if (rc)
2044 return -EPERM;
2045 }
2046
2047 /* Make sure that anyone attempting to ptrace over a task that
2048 * changes its SID has the appropriate permit */
2049 if (bprm->unsafe &
2050 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2051 struct task_struct *tracer;
2052 struct task_security_struct *sec;
2053 u32 ptsid = 0;
2054
2055 rcu_read_lock();
2056 tracer = ptrace_parent(current);
2057 if (likely(tracer != NULL)) {
2058 sec = __task_cred(tracer)->security;
2059 ptsid = sec->sid;
2060 }
2061 rcu_read_unlock();
2062
2063 if (ptsid != 0) {
2064 rc = avc_has_perm(ptsid, new_tsec->sid,
2065 SECCLASS_PROCESS,
2066 PROCESS__PTRACE, NULL);
2067 if (rc)
2068 return -EPERM;
2069 }
2070 }
2071
2072 /* Clear any possibly unsafe personality bits on exec: */
2073 bprm->per_clear |= PER_CLEAR_ON_SETID;
2074 }
2075
2076 return 0;
2077}
2078
2079static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2080{
2081 const struct task_security_struct *tsec = current_security();
2082 u32 sid, osid;
2083 int atsecure = 0;
2084
2085 sid = tsec->sid;
2086 osid = tsec->osid;
2087
2088 if (osid != sid) {
2089 /* Enable secure mode for SIDs transitions unless
2090 the noatsecure permission is granted between
2091 the two SIDs, i.e. ahp returns 0. */
2092 atsecure = avc_has_perm(osid, sid,
2093 SECCLASS_PROCESS,
2094 PROCESS__NOATSECURE, NULL);
2095 }
2096
2097 return (atsecure || cap_bprm_secureexec(bprm));
2098}
2099
2100extern struct vfsmount *selinuxfs_mount;
2101extern struct dentry *selinux_null;
2102
2103/* Derived from fs/exec.c:flush_old_files. */
2104static inline void flush_unauthorized_files(const struct cred *cred,
2105 struct files_struct *files)
2106{
2107 struct common_audit_data ad;
2108 struct file *file, *devnull = NULL;
2109 struct tty_struct *tty;
2110 struct fdtable *fdt;
2111 long j = -1;
2112 int drop_tty = 0;
2113
2114 tty = get_current_tty();
2115 if (tty) {
2116 spin_lock(&tty_files_lock);
2117 if (!list_empty(&tty->tty_files)) {
2118 struct tty_file_private *file_priv;
2119 struct inode *inode;
2120
2121 /* Revalidate access to controlling tty.
2122 Use inode_has_perm on the tty inode directly rather
2123 than using file_has_perm, as this particular open
2124 file may belong to another process and we are only
2125 interested in the inode-based check here. */
2126 file_priv = list_first_entry(&tty->tty_files,
2127 struct tty_file_private, list);
2128 file = file_priv->file;
2129 inode = file->f_path.dentry->d_inode;
2130 if (inode_has_perm_noadp(cred, inode,
2131 FILE__READ | FILE__WRITE, 0)) {
2132 drop_tty = 1;
2133 }
2134 }
2135 spin_unlock(&tty_files_lock);
2136 tty_kref_put(tty);
2137 }
2138 /* Reset controlling tty. */
2139 if (drop_tty)
2140 no_tty();
2141
2142 /* Revalidate access to inherited open files. */
2143
2144 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2145
2146 spin_lock(&files->file_lock);
2147 for (;;) {
2148 unsigned long set, i;
2149 int fd;
2150
2151 j++;
2152 i = j * __NFDBITS;
2153 fdt = files_fdtable(files);
2154 if (i >= fdt->max_fds)
2155 break;
2156 set = fdt->open_fds->fds_bits[j];
2157 if (!set)
2158 continue;
2159 spin_unlock(&files->file_lock);
2160 for ( ; set ; i++, set >>= 1) {
2161 if (set & 1) {
2162 file = fget(i);
2163 if (!file)
2164 continue;
2165 if (file_has_perm(cred,
2166 file,
2167 file_to_av(file))) {
2168 sys_close(i);
2169 fd = get_unused_fd();
2170 if (fd != i) {
2171 if (fd >= 0)
2172 put_unused_fd(fd);
2173 fput(file);
2174 continue;
2175 }
2176 if (devnull) {
2177 get_file(devnull);
2178 } else {
2179 devnull = dentry_open(
2180 dget(selinux_null),
2181 mntget(selinuxfs_mount),
2182 O_RDWR, cred);
2183 if (IS_ERR(devnull)) {
2184 devnull = NULL;
2185 put_unused_fd(fd);
2186 fput(file);
2187 continue;
2188 }
2189 }
2190 fd_install(fd, devnull);
2191 }
2192 fput(file);
2193 }
2194 }
2195 spin_lock(&files->file_lock);
2196
2197 }
2198 spin_unlock(&files->file_lock);
2199}
2200
2201/*
2202 * Prepare a process for imminent new credential changes due to exec
2203 */
2204static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2205{
2206 struct task_security_struct *new_tsec;
2207 struct rlimit *rlim, *initrlim;
2208 int rc, i;
2209
2210 new_tsec = bprm->cred->security;
2211 if (new_tsec->sid == new_tsec->osid)
2212 return;
2213
2214 /* Close files for which the new task SID is not authorized. */
2215 flush_unauthorized_files(bprm->cred, current->files);
2216
2217 /* Always clear parent death signal on SID transitions. */
2218 current->pdeath_signal = 0;
2219
2220 /* Check whether the new SID can inherit resource limits from the old
2221 * SID. If not, reset all soft limits to the lower of the current
2222 * task's hard limit and the init task's soft limit.
2223 *
2224 * Note that the setting of hard limits (even to lower them) can be
2225 * controlled by the setrlimit check. The inclusion of the init task's
2226 * soft limit into the computation is to avoid resetting soft limits
2227 * higher than the default soft limit for cases where the default is
2228 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2229 */
2230 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2231 PROCESS__RLIMITINH, NULL);
2232 if (rc) {
2233 /* protect against do_prlimit() */
2234 task_lock(current);
2235 for (i = 0; i < RLIM_NLIMITS; i++) {
2236 rlim = current->signal->rlim + i;
2237 initrlim = init_task.signal->rlim + i;
2238 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2239 }
2240 task_unlock(current);
2241 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2242 }
2243}
2244
2245/*
2246 * Clean up the process immediately after the installation of new credentials
2247 * due to exec
2248 */
2249static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2250{
2251 const struct task_security_struct *tsec = current_security();
2252 struct itimerval itimer;
2253 u32 osid, sid;
2254 int rc, i;
2255
2256 osid = tsec->osid;
2257 sid = tsec->sid;
2258
2259 if (sid == osid)
2260 return;
2261
2262 /* Check whether the new SID can inherit signal state from the old SID.
2263 * If not, clear itimers to avoid subsequent signal generation and
2264 * flush and unblock signals.
2265 *
2266 * This must occur _after_ the task SID has been updated so that any
2267 * kill done after the flush will be checked against the new SID.
2268 */
2269 rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2270 if (rc) {
2271 memset(&itimer, 0, sizeof itimer);
2272 for (i = 0; i < 3; i++)
2273 do_setitimer(i, &itimer, NULL);
2274 spin_lock_irq(¤t->sighand->siglock);
2275 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2276 __flush_signals(current);
2277 flush_signal_handlers(current, 1);
2278 sigemptyset(¤t->blocked);
2279 }
2280 spin_unlock_irq(¤t->sighand->siglock);
2281 }
2282
2283 /* Wake up the parent if it is waiting so that it can recheck
2284 * wait permission to the new task SID. */
2285 read_lock(&tasklist_lock);
2286 __wake_up_parent(current, current->real_parent);
2287 read_unlock(&tasklist_lock);
2288}
2289
2290/* superblock security operations */
2291
2292static int selinux_sb_alloc_security(struct super_block *sb)
2293{
2294 return superblock_alloc_security(sb);
2295}
2296
2297static void selinux_sb_free_security(struct super_block *sb)
2298{
2299 superblock_free_security(sb);
2300}
2301
2302static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2303{
2304 if (plen > olen)
2305 return 0;
2306
2307 return !memcmp(prefix, option, plen);
2308}
2309
2310static inline int selinux_option(char *option, int len)
2311{
2312 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2313 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2314 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2315 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2316 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2317}
2318
2319static inline void take_option(char **to, char *from, int *first, int len)
2320{
2321 if (!*first) {
2322 **to = ',';
2323 *to += 1;
2324 } else
2325 *first = 0;
2326 memcpy(*to, from, len);
2327 *to += len;
2328}
2329
2330static inline void take_selinux_option(char **to, char *from, int *first,
2331 int len)
2332{
2333 int current_size = 0;
2334
2335 if (!*first) {
2336 **to = '|';
2337 *to += 1;
2338 } else
2339 *first = 0;
2340
2341 while (current_size < len) {
2342 if (*from != '"') {
2343 **to = *from;
2344 *to += 1;
2345 }
2346 from += 1;
2347 current_size += 1;
2348 }
2349}
2350
2351static int selinux_sb_copy_data(char *orig, char *copy)
2352{
2353 int fnosec, fsec, rc = 0;
2354 char *in_save, *in_curr, *in_end;
2355 char *sec_curr, *nosec_save, *nosec;
2356 int open_quote = 0;
2357
2358 in_curr = orig;
2359 sec_curr = copy;
2360
2361 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2362 if (!nosec) {
2363 rc = -ENOMEM;
2364 goto out;
2365 }
2366
2367 nosec_save = nosec;
2368 fnosec = fsec = 1;
2369 in_save = in_end = orig;
2370
2371 do {
2372 if (*in_end == '"')
2373 open_quote = !open_quote;
2374 if ((*in_end == ',' && open_quote == 0) ||
2375 *in_end == '\0') {
2376 int len = in_end - in_curr;
2377
2378 if (selinux_option(in_curr, len))
2379 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2380 else
2381 take_option(&nosec, in_curr, &fnosec, len);
2382
2383 in_curr = in_end + 1;
2384 }
2385 } while (*in_end++);
2386
2387 strcpy(in_save, nosec_save);
2388 free_page((unsigned long)nosec_save);
2389out:
2390 return rc;
2391}
2392
2393static int selinux_sb_remount(struct super_block *sb, void *data)
2394{
2395 int rc, i, *flags;
2396 struct security_mnt_opts opts;
2397 char *secdata, **mount_options;
2398 struct superblock_security_struct *sbsec = sb->s_security;
2399
2400 if (!(sbsec->flags & SE_SBINITIALIZED))
2401 return 0;
2402
2403 if (!data)
2404 return 0;
2405
2406 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2407 return 0;
2408
2409 security_init_mnt_opts(&opts);
2410 secdata = alloc_secdata();
2411 if (!secdata)
2412 return -ENOMEM;
2413 rc = selinux_sb_copy_data(data, secdata);
2414 if (rc)
2415 goto out_free_secdata;
2416
2417 rc = selinux_parse_opts_str(secdata, &opts);
2418 if (rc)
2419 goto out_free_secdata;
2420
2421 mount_options = opts.mnt_opts;
2422 flags = opts.mnt_opts_flags;
2423
2424 for (i = 0; i < opts.num_mnt_opts; i++) {
2425 u32 sid;
2426 size_t len;
2427
2428 if (flags[i] == SE_SBLABELSUPP)
2429 continue;
2430 len = strlen(mount_options[i]);
2431 rc = security_context_to_sid(mount_options[i], len, &sid);
2432 if (rc) {
2433 printk(KERN_WARNING "SELinux: security_context_to_sid"
2434 "(%s) failed for (dev %s, type %s) errno=%d\n",
2435 mount_options[i], sb->s_id, sb->s_type->name, rc);
2436 goto out_free_opts;
2437 }
2438 rc = -EINVAL;
2439 switch (flags[i]) {
2440 case FSCONTEXT_MNT:
2441 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2442 goto out_bad_option;
2443 break;
2444 case CONTEXT_MNT:
2445 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2446 goto out_bad_option;
2447 break;
2448 case ROOTCONTEXT_MNT: {
2449 struct inode_security_struct *root_isec;
2450 root_isec = sb->s_root->d_inode->i_security;
2451
2452 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2453 goto out_bad_option;
2454 break;
2455 }
2456 case DEFCONTEXT_MNT:
2457 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2458 goto out_bad_option;
2459 break;
2460 default:
2461 goto out_free_opts;
2462 }
2463 }
2464
2465 rc = 0;
2466out_free_opts:
2467 security_free_mnt_opts(&opts);
2468out_free_secdata:
2469 free_secdata(secdata);
2470 return rc;
2471out_bad_option:
2472 printk(KERN_WARNING "SELinux: unable to change security options "
2473 "during remount (dev %s, type=%s)\n", sb->s_id,
2474 sb->s_type->name);
2475 goto out_free_opts;
2476}
2477
2478static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2479{
2480 const struct cred *cred = current_cred();
2481 struct common_audit_data ad;
2482 int rc;
2483
2484 rc = superblock_doinit(sb, data);
2485 if (rc)
2486 return rc;
2487
2488 /* Allow all mounts performed by the kernel */
2489 if (flags & MS_KERNMOUNT)
2490 return 0;
2491
2492 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2493 ad.u.dentry = sb->s_root;
2494 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2495}
2496
2497static int selinux_sb_statfs(struct dentry *dentry)
2498{
2499 const struct cred *cred = current_cred();
2500 struct common_audit_data ad;
2501
2502 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2503 ad.u.dentry = dentry->d_sb->s_root;
2504 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2505}
2506
2507static int selinux_mount(char *dev_name,
2508 struct path *path,
2509 char *type,
2510 unsigned long flags,
2511 void *data)
2512{
2513 const struct cred *cred = current_cred();
2514
2515 if (flags & MS_REMOUNT)
2516 return superblock_has_perm(cred, path->mnt->mnt_sb,
2517 FILESYSTEM__REMOUNT, NULL);
2518 else
2519 return path_has_perm(cred, path, FILE__MOUNTON);
2520}
2521
2522static int selinux_umount(struct vfsmount *mnt, int flags)
2523{
2524 const struct cred *cred = current_cred();
2525
2526 return superblock_has_perm(cred, mnt->mnt_sb,
2527 FILESYSTEM__UNMOUNT, NULL);
2528}
2529
2530/* inode security operations */
2531
2532static int selinux_inode_alloc_security(struct inode *inode)
2533{
2534 return inode_alloc_security(inode);
2535}
2536
2537static void selinux_inode_free_security(struct inode *inode)
2538{
2539 inode_free_security(inode);
2540}
2541
2542static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2543 const struct qstr *qstr, char **name,
2544 void **value, size_t *len)
2545{
2546 const struct task_security_struct *tsec = current_security();
2547 struct inode_security_struct *dsec;
2548 struct superblock_security_struct *sbsec;
2549 u32 sid, newsid, clen;
2550 int rc;
2551 char *namep = NULL, *context;
2552
2553 dsec = dir->i_security;
2554 sbsec = dir->i_sb->s_security;
2555
2556 sid = tsec->sid;
2557 newsid = tsec->create_sid;
2558
2559 if ((sbsec->flags & SE_SBINITIALIZED) &&
2560 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2561 newsid = sbsec->mntpoint_sid;
2562 else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2563 rc = security_transition_sid(sid, dsec->sid,
2564 inode_mode_to_security_class(inode->i_mode),
2565 qstr, &newsid);
2566 if (rc) {
2567 printk(KERN_WARNING "%s: "
2568 "security_transition_sid failed, rc=%d (dev=%s "
2569 "ino=%ld)\n",
2570 __func__,
2571 -rc, inode->i_sb->s_id, inode->i_ino);
2572 return rc;
2573 }
2574 }
2575
2576 /* Possibly defer initialization to selinux_complete_init. */
2577 if (sbsec->flags & SE_SBINITIALIZED) {
2578 struct inode_security_struct *isec = inode->i_security;
2579 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2580 isec->sid = newsid;
2581 isec->initialized = 1;
2582 }
2583
2584 if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2585 return -EOPNOTSUPP;
2586
2587 if (name) {
2588 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2589 if (!namep)
2590 return -ENOMEM;
2591 *name = namep;
2592 }
2593
2594 if (value && len) {
2595 rc = security_sid_to_context_force(newsid, &context, &clen);
2596 if (rc) {
2597 kfree(namep);
2598 return rc;
2599 }
2600 *value = context;
2601 *len = clen;
2602 }
2603
2604 return 0;
2605}
2606
2607static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2608{
2609 return may_create(dir, dentry, SECCLASS_FILE);
2610}
2611
2612static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2613{
2614 return may_link(dir, old_dentry, MAY_LINK);
2615}
2616
2617static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2618{
2619 return may_link(dir, dentry, MAY_UNLINK);
2620}
2621
2622static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2623{
2624 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2625}
2626
2627static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2628{
2629 return may_create(dir, dentry, SECCLASS_DIR);
2630}
2631
2632static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2633{
2634 return may_link(dir, dentry, MAY_RMDIR);
2635}
2636
2637static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2638{
2639 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2640}
2641
2642static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2643 struct inode *new_inode, struct dentry *new_dentry)
2644{
2645 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2646}
2647
2648static int selinux_inode_readlink(struct dentry *dentry)
2649{
2650 const struct cred *cred = current_cred();
2651
2652 return dentry_has_perm(cred, dentry, FILE__READ);
2653}
2654
2655static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2656{
2657 const struct cred *cred = current_cred();
2658
2659 return dentry_has_perm(cred, dentry, FILE__READ);
2660}
2661
2662static int selinux_inode_permission(struct inode *inode, int mask)
2663{
2664 const struct cred *cred = current_cred();
2665 struct common_audit_data ad;
2666 u32 perms;
2667 bool from_access;
2668 unsigned flags = mask & MAY_NOT_BLOCK;
2669
2670 from_access = mask & MAY_ACCESS;
2671 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2672
2673 /* No permission to check. Existence test. */
2674 if (!mask)
2675 return 0;
2676
2677 COMMON_AUDIT_DATA_INIT(&ad, INODE);
2678 ad.u.inode = inode;
2679
2680 if (from_access)
2681 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2682
2683 perms = file_mask_to_av(inode->i_mode, mask);
2684
2685 return inode_has_perm(cred, inode, perms, &ad, flags);
2686}
2687
2688static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2689{
2690 const struct cred *cred = current_cred();
2691 unsigned int ia_valid = iattr->ia_valid;
2692
2693 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2694 if (ia_valid & ATTR_FORCE) {
2695 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2696 ATTR_FORCE);
2697 if (!ia_valid)
2698 return 0;
2699 }
2700
2701 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2702 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2703 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2704
2705 return dentry_has_perm(cred, dentry, FILE__WRITE);
2706}
2707
2708static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2709{
2710 const struct cred *cred = current_cred();
2711 struct path path;
2712
2713 path.dentry = dentry;
2714 path.mnt = mnt;
2715
2716 return path_has_perm(cred, &path, FILE__GETATTR);
2717}
2718
2719static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2720{
2721 const struct cred *cred = current_cred();
2722
2723 if (!strncmp(name, XATTR_SECURITY_PREFIX,
2724 sizeof XATTR_SECURITY_PREFIX - 1)) {
2725 if (!strcmp(name, XATTR_NAME_CAPS)) {
2726 if (!capable(CAP_SETFCAP))
2727 return -EPERM;
2728 } else if (!capable(CAP_SYS_ADMIN)) {
2729 /* A different attribute in the security namespace.
2730 Restrict to administrator. */
2731 return -EPERM;
2732 }
2733 }
2734
2735 /* Not an attribute we recognize, so just check the
2736 ordinary setattr permission. */
2737 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2738}
2739
2740static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2741 const void *value, size_t size, int flags)
2742{
2743 struct inode *inode = dentry->d_inode;
2744 struct inode_security_struct *isec = inode->i_security;
2745 struct superblock_security_struct *sbsec;
2746 struct common_audit_data ad;
2747 u32 newsid, sid = current_sid();
2748 int rc = 0;
2749
2750 if (strcmp(name, XATTR_NAME_SELINUX))
2751 return selinux_inode_setotherxattr(dentry, name);
2752
2753 sbsec = inode->i_sb->s_security;
2754 if (!(sbsec->flags & SE_SBLABELSUPP))
2755 return -EOPNOTSUPP;
2756
2757 if (!inode_owner_or_capable(inode))
2758 return -EPERM;
2759
2760 COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2761 ad.u.dentry = dentry;
2762
2763 rc = avc_has_perm(sid, isec->sid, isec->sclass,
2764 FILE__RELABELFROM, &ad);
2765 if (rc)
2766 return rc;
2767
2768 rc = security_context_to_sid(value, size, &newsid);
2769 if (rc == -EINVAL) {
2770 if (!capable(CAP_MAC_ADMIN))
2771 return rc;
2772 rc = security_context_to_sid_force(value, size, &newsid);
2773 }
2774 if (rc)
2775 return rc;
2776
2777 rc = avc_has_perm(sid, newsid, isec->sclass,
2778 FILE__RELABELTO, &ad);
2779 if (rc)
2780 return rc;
2781
2782 rc = security_validate_transition(isec->sid, newsid, sid,
2783 isec->sclass);
2784 if (rc)
2785 return rc;
2786
2787 return avc_has_perm(newsid,
2788 sbsec->sid,
2789 SECCLASS_FILESYSTEM,
2790 FILESYSTEM__ASSOCIATE,
2791 &ad);
2792}
2793
2794static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2795 const void *value, size_t size,
2796 int flags)
2797{
2798 struct inode *inode = dentry->d_inode;
2799 struct inode_security_struct *isec = inode->i_security;
2800 u32 newsid;
2801 int rc;
2802
2803 if (strcmp(name, XATTR_NAME_SELINUX)) {
2804 /* Not an attribute we recognize, so nothing to do. */
2805 return;
2806 }
2807
2808 rc = security_context_to_sid_force(value, size, &newsid);
2809 if (rc) {
2810 printk(KERN_ERR "SELinux: unable to map context to SID"
2811 "for (%s, %lu), rc=%d\n",
2812 inode->i_sb->s_id, inode->i_ino, -rc);
2813 return;
2814 }
2815
2816 isec->sid = newsid;
2817 return;
2818}
2819
2820static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2821{
2822 const struct cred *cred = current_cred();
2823
2824 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2825}
2826
2827static int selinux_inode_listxattr(struct dentry *dentry)
2828{
2829 const struct cred *cred = current_cred();
2830
2831 return dentry_has_perm(cred, dentry, FILE__GETATTR);
2832}
2833
2834static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2835{
2836 if (strcmp(name, XATTR_NAME_SELINUX))
2837 return selinux_inode_setotherxattr(dentry, name);
2838
2839 /* No one is allowed to remove a SELinux security label.
2840 You can change the label, but all data must be labeled. */
2841 return -EACCES;
2842}
2843
2844/*
2845 * Copy the inode security context value to the user.
2846 *
2847 * Permission check is handled by selinux_inode_getxattr hook.
2848 */
2849static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2850{
2851 u32 size;
2852 int error;
2853 char *context = NULL;
2854 struct inode_security_struct *isec = inode->i_security;
2855
2856 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2857 return -EOPNOTSUPP;
2858
2859 /*
2860 * If the caller has CAP_MAC_ADMIN, then get the raw context
2861 * value even if it is not defined by current policy; otherwise,
2862 * use the in-core value under current policy.
2863 * Use the non-auditing forms of the permission checks since
2864 * getxattr may be called by unprivileged processes commonly
2865 * and lack of permission just means that we fall back to the
2866 * in-core context value, not a denial.
2867 */
2868 error = selinux_capable(current, current_cred(),
2869 &init_user_ns, CAP_MAC_ADMIN,
2870 SECURITY_CAP_NOAUDIT);
2871 if (!error)
2872 error = security_sid_to_context_force(isec->sid, &context,
2873 &size);
2874 else
2875 error = security_sid_to_context(isec->sid, &context, &size);
2876 if (error)
2877 return error;
2878 error = size;
2879 if (alloc) {
2880 *buffer = context;
2881 goto out_nofree;
2882 }
2883 kfree(context);
2884out_nofree:
2885 return error;
2886}
2887
2888static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2889 const void *value, size_t size, int flags)
2890{
2891 struct inode_security_struct *isec = inode->i_security;
2892 u32 newsid;
2893 int rc;
2894
2895 if (strcmp(name, XATTR_SELINUX_SUFFIX))
2896 return -EOPNOTSUPP;
2897
2898 if (!value || !size)
2899 return -EACCES;
2900
2901 rc = security_context_to_sid((void *)value, size, &newsid);
2902 if (rc)
2903 return rc;
2904
2905 isec->sid = newsid;
2906 isec->initialized = 1;
2907 return 0;
2908}
2909
2910static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2911{
2912 const int len = sizeof(XATTR_NAME_SELINUX);
2913 if (buffer && len <= buffer_size)
2914 memcpy(buffer, XATTR_NAME_SELINUX, len);
2915 return len;
2916}
2917
2918static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2919{
2920 struct inode_security_struct *isec = inode->i_security;
2921 *secid = isec->sid;
2922}
2923
2924/* file security operations */
2925
2926static int selinux_revalidate_file_permission(struct file *file, int mask)
2927{
2928 const struct cred *cred = current_cred();
2929 struct inode *inode = file->f_path.dentry->d_inode;
2930
2931 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2932 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2933 mask |= MAY_APPEND;
2934
2935 return file_has_perm(cred, file,
2936 file_mask_to_av(inode->i_mode, mask));
2937}
2938
2939static int selinux_file_permission(struct file *file, int mask)
2940{
2941 struct inode *inode = file->f_path.dentry->d_inode;
2942 struct file_security_struct *fsec = file->f_security;
2943 struct inode_security_struct *isec = inode->i_security;
2944 u32 sid = current_sid();
2945
2946 if (!mask)
2947 /* No permission to check. Existence test. */
2948 return 0;
2949
2950 if (sid == fsec->sid && fsec->isid == isec->sid &&
2951 fsec->pseqno == avc_policy_seqno())
2952 /* No change since dentry_open check. */
2953 return 0;
2954
2955 return selinux_revalidate_file_permission(file, mask);
2956}
2957
2958static int selinux_file_alloc_security(struct file *file)
2959{
2960 return file_alloc_security(file);
2961}
2962
2963static void selinux_file_free_security(struct file *file)
2964{
2965 file_free_security(file);
2966}
2967
2968static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2969 unsigned long arg)
2970{
2971 const struct cred *cred = current_cred();
2972 int error = 0;
2973
2974 switch (cmd) {
2975 case FIONREAD:
2976 /* fall through */
2977 case FIBMAP:
2978 /* fall through */
2979 case FIGETBSZ:
2980 /* fall through */
2981 case EXT2_IOC_GETFLAGS:
2982 /* fall through */
2983 case EXT2_IOC_GETVERSION:
2984 error = file_has_perm(cred, file, FILE__GETATTR);
2985 break;
2986
2987 case EXT2_IOC_SETFLAGS:
2988 /* fall through */
2989 case EXT2_IOC_SETVERSION:
2990 error = file_has_perm(cred, file, FILE__SETATTR);
2991 break;
2992
2993 /* sys_ioctl() checks */
2994 case FIONBIO:
2995 /* fall through */
2996 case FIOASYNC:
2997 error = file_has_perm(cred, file, 0);
2998 break;
2999
3000 case KDSKBENT:
3001 case KDSKBSENT:
3002 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
3003 SECURITY_CAP_AUDIT);
3004 break;
3005
3006 /* default case assumes that the command will go
3007 * to the file's ioctl() function.
3008 */
3009 default:
3010 error = file_has_perm(cred, file, FILE__IOCTL);
3011 }
3012 return error;
3013}
3014
3015static int default_noexec;
3016
3017static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3018{
3019 const struct cred *cred = current_cred();
3020 int rc = 0;
3021
3022 if (default_noexec &&
3023 (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3024 /*
3025 * We are making executable an anonymous mapping or a
3026 * private file mapping that will also be writable.
3027 * This has an additional check.
3028 */
3029 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3030 if (rc)
3031 goto error;
3032 }
3033
3034 if (file) {
3035 /* read access is always possible with a mapping */
3036 u32 av = FILE__READ;
3037
3038 /* write access only matters if the mapping is shared */
3039 if (shared && (prot & PROT_WRITE))
3040 av |= FILE__WRITE;
3041
3042 if (prot & PROT_EXEC)
3043 av |= FILE__EXECUTE;
3044
3045 return file_has_perm(cred, file, av);
3046 }
3047
3048error:
3049 return rc;
3050}
3051
3052static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3053 unsigned long prot, unsigned long flags,
3054 unsigned long addr, unsigned long addr_only)
3055{
3056 int rc = 0;
3057 u32 sid = current_sid();
3058
3059 /*
3060 * notice that we are intentionally putting the SELinux check before
3061 * the secondary cap_file_mmap check. This is such a likely attempt
3062 * at bad behaviour/exploit that we always want to get the AVC, even
3063 * if DAC would have also denied the operation.
3064 */
3065 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3066 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3067 MEMPROTECT__MMAP_ZERO, NULL);
3068 if (rc)
3069 return rc;
3070 }
3071
3072 /* do DAC check on address space usage */
3073 rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3074 if (rc || addr_only)
3075 return rc;
3076
3077 if (selinux_checkreqprot)
3078 prot = reqprot;
3079
3080 return file_map_prot_check(file, prot,
3081 (flags & MAP_TYPE) == MAP_SHARED);
3082}
3083
3084static int selinux_file_mprotect(struct vm_area_struct *vma,
3085 unsigned long reqprot,
3086 unsigned long prot)
3087{
3088 const struct cred *cred = current_cred();
3089
3090 if (selinux_checkreqprot)
3091 prot = reqprot;
3092
3093 if (default_noexec &&
3094 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3095 int rc = 0;
3096 if (vma->vm_start >= vma->vm_mm->start_brk &&
3097 vma->vm_end <= vma->vm_mm->brk) {
3098 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3099 } else if (!vma->vm_file &&
3100 vma->vm_start <= vma->vm_mm->start_stack &&
3101 vma->vm_end >= vma->vm_mm->start_stack) {
3102 rc = current_has_perm(current, PROCESS__EXECSTACK);
3103 } else if (vma->vm_file && vma->anon_vma) {
3104 /*
3105 * We are making executable a file mapping that has
3106 * had some COW done. Since pages might have been
3107 * written, check ability to execute the possibly
3108 * modified content. This typically should only
3109 * occur for text relocations.
3110 */
3111 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3112 }
3113 if (rc)
3114 return rc;
3115 }
3116
3117 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3118}
3119
3120static int selinux_file_lock(struct file *file, unsigned int cmd)
3121{
3122 const struct cred *cred = current_cred();
3123
3124 return file_has_perm(cred, file, FILE__LOCK);
3125}
3126
3127static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3128 unsigned long arg)
3129{
3130 const struct cred *cred = current_cred();
3131 int err = 0;
3132
3133 switch (cmd) {
3134 case F_SETFL:
3135 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3136 err = -EINVAL;
3137 break;
3138 }
3139
3140 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3141 err = file_has_perm(cred, file, FILE__WRITE);
3142 break;
3143 }
3144 /* fall through */
3145 case F_SETOWN:
3146 case F_SETSIG:
3147 case F_GETFL:
3148 case F_GETOWN:
3149 case F_GETSIG:
3150 /* Just check FD__USE permission */
3151 err = file_has_perm(cred, file, 0);
3152 break;
3153 case F_GETLK:
3154 case F_SETLK:
3155 case F_SETLKW:
3156#if BITS_PER_LONG == 32
3157 case F_GETLK64:
3158 case F_SETLK64:
3159 case F_SETLKW64:
3160#endif
3161 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3162 err = -EINVAL;
3163 break;
3164 }
3165 err = file_has_perm(cred, file, FILE__LOCK);
3166 break;
3167 }
3168
3169 return err;
3170}
3171
3172static int selinux_file_set_fowner(struct file *file)
3173{
3174 struct file_security_struct *fsec;
3175
3176 fsec = file->f_security;
3177 fsec->fown_sid = current_sid();
3178
3179 return 0;
3180}
3181
3182static int selinux_file_send_sigiotask(struct task_struct *tsk,
3183 struct fown_struct *fown, int signum)
3184{
3185 struct file *file;
3186 u32 sid = task_sid(tsk);
3187 u32 perm;
3188 struct file_security_struct *fsec;
3189
3190 /* struct fown_struct is never outside the context of a struct file */
3191 file = container_of(fown, struct file, f_owner);
3192
3193 fsec = file->f_security;
3194
3195 if (!signum)
3196 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3197 else
3198 perm = signal_to_av(signum);
3199
3200 return avc_has_perm(fsec->fown_sid, sid,
3201 SECCLASS_PROCESS, perm, NULL);
3202}
3203
3204static int selinux_file_receive(struct file *file)
3205{
3206 const struct cred *cred = current_cred();
3207
3208 return file_has_perm(cred, file, file_to_av(file));
3209}
3210
3211static int selinux_dentry_open(struct file *file, const struct cred *cred)
3212{
3213 struct file_security_struct *fsec;
3214 struct inode *inode;
3215 struct inode_security_struct *isec;
3216
3217 inode = file->f_path.dentry->d_inode;
3218 fsec = file->f_security;
3219 isec = inode->i_security;
3220 /*
3221 * Save inode label and policy sequence number
3222 * at open-time so that selinux_file_permission
3223 * can determine whether revalidation is necessary.
3224 * Task label is already saved in the file security
3225 * struct as its SID.
3226 */
3227 fsec->isid = isec->sid;
3228 fsec->pseqno = avc_policy_seqno();
3229 /*
3230 * Since the inode label or policy seqno may have changed
3231 * between the selinux_inode_permission check and the saving
3232 * of state above, recheck that access is still permitted.
3233 * Otherwise, access might never be revalidated against the
3234 * new inode label or new policy.
3235 * This check is not redundant - do not remove.
3236 */
3237 return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3238}
3239
3240/* task security operations */
3241
3242static int selinux_task_create(unsigned long clone_flags)
3243{
3244 return current_has_perm(current, PROCESS__FORK);
3245}
3246
3247/*
3248 * allocate the SELinux part of blank credentials
3249 */
3250static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3251{
3252 struct task_security_struct *tsec;
3253
3254 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3255 if (!tsec)
3256 return -ENOMEM;
3257
3258 cred->security = tsec;
3259 return 0;
3260}
3261
3262/*
3263 * detach and free the LSM part of a set of credentials
3264 */
3265static void selinux_cred_free(struct cred *cred)
3266{
3267 struct task_security_struct *tsec = cred->security;
3268
3269 /*
3270 * cred->security == NULL if security_cred_alloc_blank() or
3271 * security_prepare_creds() returned an error.
3272 */
3273 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3274 cred->security = (void *) 0x7UL;
3275 kfree(tsec);
3276}
3277
3278/*
3279 * prepare a new set of credentials for modification
3280 */
3281static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3282 gfp_t gfp)
3283{
3284 const struct task_security_struct *old_tsec;
3285 struct task_security_struct *tsec;
3286
3287 old_tsec = old->security;
3288
3289 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3290 if (!tsec)
3291 return -ENOMEM;
3292
3293 new->security = tsec;
3294 return 0;
3295}
3296
3297/*
3298 * transfer the SELinux data to a blank set of creds
3299 */
3300static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3301{
3302 const struct task_security_struct *old_tsec = old->security;
3303 struct task_security_struct *tsec = new->security;
3304
3305 *tsec = *old_tsec;
3306}
3307
3308/*
3309 * set the security data for a kernel service
3310 * - all the creation contexts are set to unlabelled
3311 */
3312static int selinux_kernel_act_as(struct cred *new, u32 secid)
3313{
3314 struct task_security_struct *tsec = new->security;
3315 u32 sid = current_sid();
3316 int ret;
3317
3318 ret = avc_has_perm(sid, secid,
3319 SECCLASS_KERNEL_SERVICE,
3320 KERNEL_SERVICE__USE_AS_OVERRIDE,
3321 NULL);
3322 if (ret == 0) {
3323 tsec->sid = secid;
3324 tsec->create_sid = 0;
3325 tsec->keycreate_sid = 0;
3326 tsec->sockcreate_sid = 0;
3327 }
3328 return ret;
3329}
3330
3331/*
3332 * set the file creation context in a security record to the same as the
3333 * objective context of the specified inode
3334 */
3335static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3336{
3337 struct inode_security_struct *isec = inode->i_security;
3338 struct task_security_struct *tsec = new->security;
3339 u32 sid = current_sid();
3340 int ret;
3341
3342 ret = avc_has_perm(sid, isec->sid,
3343 SECCLASS_KERNEL_SERVICE,
3344 KERNEL_SERVICE__CREATE_FILES_AS,
3345 NULL);
3346
3347 if (ret == 0)
3348 tsec->create_sid = isec->sid;
3349 return ret;
3350}
3351
3352static int selinux_kernel_module_request(char *kmod_name)
3353{
3354 u32 sid;
3355 struct common_audit_data ad;
3356
3357 sid = task_sid(current);
3358
3359 COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3360 ad.u.kmod_name = kmod_name;
3361
3362 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3363 SYSTEM__MODULE_REQUEST, &ad);
3364}
3365
3366static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3367{
3368 return current_has_perm(p, PROCESS__SETPGID);
3369}
3370
3371static int selinux_task_getpgid(struct task_struct *p)
3372{
3373 return current_has_perm(p, PROCESS__GETPGID);
3374}
3375
3376static int selinux_task_getsid(struct task_struct *p)
3377{
3378 return current_has_perm(p, PROCESS__GETSESSION);
3379}
3380
3381static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3382{
3383 *secid = task_sid(p);
3384}
3385
3386static int selinux_task_setnice(struct task_struct *p, int nice)
3387{
3388 int rc;
3389
3390 rc = cap_task_setnice(p, nice);
3391 if (rc)
3392 return rc;
3393
3394 return current_has_perm(p, PROCESS__SETSCHED);
3395}
3396
3397static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3398{
3399 int rc;
3400
3401 rc = cap_task_setioprio(p, ioprio);
3402 if (rc)
3403 return rc;
3404
3405 return current_has_perm(p, PROCESS__SETSCHED);
3406}
3407
3408static int selinux_task_getioprio(struct task_struct *p)
3409{
3410 return current_has_perm(p, PROCESS__GETSCHED);
3411}
3412
3413static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3414 struct rlimit *new_rlim)
3415{
3416 struct rlimit *old_rlim = p->signal->rlim + resource;
3417
3418 /* Control the ability to change the hard limit (whether
3419 lowering or raising it), so that the hard limit can
3420 later be used as a safe reset point for the soft limit
3421 upon context transitions. See selinux_bprm_committing_creds. */
3422 if (old_rlim->rlim_max != new_rlim->rlim_max)
3423 return current_has_perm(p, PROCESS__SETRLIMIT);
3424
3425 return 0;
3426}
3427
3428static int selinux_task_setscheduler(struct task_struct *p)
3429{
3430 int rc;
3431
3432 rc = cap_task_setscheduler(p);
3433 if (rc)
3434 return rc;
3435
3436 return current_has_perm(p, PROCESS__SETSCHED);
3437}
3438
3439static int selinux_task_getscheduler(struct task_struct *p)
3440{
3441 return current_has_perm(p, PROCESS__GETSCHED);
3442}
3443
3444static int selinux_task_movememory(struct task_struct *p)
3445{
3446 return current_has_perm(p, PROCESS__SETSCHED);
3447}
3448
3449static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3450 int sig, u32 secid)
3451{
3452 u32 perm;
3453 int rc;
3454
3455 if (!sig)
3456 perm = PROCESS__SIGNULL; /* null signal; existence test */
3457 else
3458 perm = signal_to_av(sig);
3459 if (secid)
3460 rc = avc_has_perm(secid, task_sid(p),
3461 SECCLASS_PROCESS, perm, NULL);
3462 else
3463 rc = current_has_perm(p, perm);
3464 return rc;
3465}
3466
3467static int selinux_task_wait(struct task_struct *p)
3468{
3469 return task_has_perm(p, current, PROCESS__SIGCHLD);
3470}
3471
3472static void selinux_task_to_inode(struct task_struct *p,
3473 struct inode *inode)
3474{
3475 struct inode_security_struct *isec = inode->i_security;
3476 u32 sid = task_sid(p);
3477
3478 isec->sid = sid;
3479 isec->initialized = 1;
3480}
3481
3482/* Returns error only if unable to parse addresses */
3483static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3484 struct common_audit_data *ad, u8 *proto)
3485{
3486 int offset, ihlen, ret = -EINVAL;
3487 struct iphdr _iph, *ih;
3488
3489 offset = skb_network_offset(skb);
3490 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3491 if (ih == NULL)
3492 goto out;
3493
3494 ihlen = ih->ihl * 4;
3495 if (ihlen < sizeof(_iph))
3496 goto out;
3497
3498 ad->u.net.v4info.saddr = ih->saddr;
3499 ad->u.net.v4info.daddr = ih->daddr;
3500 ret = 0;
3501
3502 if (proto)
3503 *proto = ih->protocol;
3504
3505 switch (ih->protocol) {
3506 case IPPROTO_TCP: {
3507 struct tcphdr _tcph, *th;
3508
3509 if (ntohs(ih->frag_off) & IP_OFFSET)
3510 break;
3511
3512 offset += ihlen;
3513 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3514 if (th == NULL)
3515 break;
3516
3517 ad->u.net.sport = th->source;
3518 ad->u.net.dport = th->dest;
3519 break;
3520 }
3521
3522 case IPPROTO_UDP: {
3523 struct udphdr _udph, *uh;
3524
3525 if (ntohs(ih->frag_off) & IP_OFFSET)
3526 break;
3527
3528 offset += ihlen;
3529 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3530 if (uh == NULL)
3531 break;
3532
3533 ad->u.net.sport = uh->source;
3534 ad->u.net.dport = uh->dest;
3535 break;
3536 }
3537
3538 case IPPROTO_DCCP: {
3539 struct dccp_hdr _dccph, *dh;
3540
3541 if (ntohs(ih->frag_off) & IP_OFFSET)
3542 break;
3543
3544 offset += ihlen;
3545 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3546 if (dh == NULL)
3547 break;
3548
3549 ad->u.net.sport = dh->dccph_sport;
3550 ad->u.net.dport = dh->dccph_dport;
3551 break;
3552 }
3553
3554 default:
3555 break;
3556 }
3557out:
3558 return ret;
3559}
3560
3561#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3562
3563/* Returns error only if unable to parse addresses */
3564static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3565 struct common_audit_data *ad, u8 *proto)
3566{
3567 u8 nexthdr;
3568 int ret = -EINVAL, offset;
3569 struct ipv6hdr _ipv6h, *ip6;
3570
3571 offset = skb_network_offset(skb);
3572 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3573 if (ip6 == NULL)
3574 goto out;
3575
3576 ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3577 ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3578 ret = 0;
3579
3580 nexthdr = ip6->nexthdr;
3581 offset += sizeof(_ipv6h);
3582 offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3583 if (offset < 0)
3584 goto out;
3585
3586 if (proto)
3587 *proto = nexthdr;
3588
3589 switch (nexthdr) {
3590 case IPPROTO_TCP: {
3591 struct tcphdr _tcph, *th;
3592
3593 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3594 if (th == NULL)
3595 break;
3596
3597 ad->u.net.sport = th->source;
3598 ad->u.net.dport = th->dest;
3599 break;
3600 }
3601
3602 case IPPROTO_UDP: {
3603 struct udphdr _udph, *uh;
3604
3605 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3606 if (uh == NULL)
3607 break;
3608
3609 ad->u.net.sport = uh->source;
3610 ad->u.net.dport = uh->dest;
3611 break;
3612 }
3613
3614 case IPPROTO_DCCP: {
3615 struct dccp_hdr _dccph, *dh;
3616
3617 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3618 if (dh == NULL)
3619 break;
3620
3621 ad->u.net.sport = dh->dccph_sport;
3622 ad->u.net.dport = dh->dccph_dport;
3623 break;
3624 }
3625
3626 /* includes fragments */
3627 default:
3628 break;
3629 }
3630out:
3631 return ret;
3632}
3633
3634#endif /* IPV6 */
3635
3636static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3637 char **_addrp, int src, u8 *proto)
3638{
3639 char *addrp;
3640 int ret;
3641
3642 switch (ad->u.net.family) {
3643 case PF_INET:
3644 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3645 if (ret)
3646 goto parse_error;
3647 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3648 &ad->u.net.v4info.daddr);
3649 goto okay;
3650
3651#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3652 case PF_INET6:
3653 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3654 if (ret)
3655 goto parse_error;
3656 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3657 &ad->u.net.v6info.daddr);
3658 goto okay;
3659#endif /* IPV6 */
3660 default:
3661 addrp = NULL;
3662 goto okay;
3663 }
3664
3665parse_error:
3666 printk(KERN_WARNING
3667 "SELinux: failure in selinux_parse_skb(),"
3668 " unable to parse packet\n");
3669 return ret;
3670
3671okay:
3672 if (_addrp)
3673 *_addrp = addrp;
3674 return 0;
3675}
3676
3677/**
3678 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3679 * @skb: the packet
3680 * @family: protocol family
3681 * @sid: the packet's peer label SID
3682 *
3683 * Description:
3684 * Check the various different forms of network peer labeling and determine
3685 * the peer label/SID for the packet; most of the magic actually occurs in
3686 * the security server function security_net_peersid_cmp(). The function
3687 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3688 * or -EACCES if @sid is invalid due to inconsistencies with the different
3689 * peer labels.
3690 *
3691 */
3692static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3693{
3694 int err;
3695 u32 xfrm_sid;
3696 u32 nlbl_sid;
3697 u32 nlbl_type;
3698
3699 selinux_skb_xfrm_sid(skb, &xfrm_sid);
3700 selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3701
3702 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3703 if (unlikely(err)) {
3704 printk(KERN_WARNING
3705 "SELinux: failure in selinux_skb_peerlbl_sid(),"
3706 " unable to determine packet's peer label\n");
3707 return -EACCES;
3708 }
3709
3710 return 0;
3711}
3712
3713/* socket security operations */
3714
3715static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3716 u16 secclass, u32 *socksid)
3717{
3718 if (tsec->sockcreate_sid > SECSID_NULL) {
3719 *socksid = tsec->sockcreate_sid;
3720 return 0;
3721 }
3722
3723 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3724 socksid);
3725}
3726
3727static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3728{
3729 struct sk_security_struct *sksec = sk->sk_security;
3730 struct common_audit_data ad;
3731 u32 tsid = task_sid(task);
3732
3733 if (sksec->sid == SECINITSID_KERNEL)
3734 return 0;
3735
3736 COMMON_AUDIT_DATA_INIT(&ad, NET);
3737 ad.u.net.sk = sk;
3738
3739 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3740}
3741
3742static int selinux_socket_create(int family, int type,
3743 int protocol, int kern)
3744{
3745 const struct task_security_struct *tsec = current_security();
3746 u32 newsid;
3747 u16 secclass;
3748 int rc;
3749
3750 if (kern)
3751 return 0;
3752
3753 secclass = socket_type_to_security_class(family, type, protocol);
3754 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3755 if (rc)
3756 return rc;
3757
3758 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3759}
3760
3761static int selinux_socket_post_create(struct socket *sock, int family,
3762 int type, int protocol, int kern)
3763{
3764 const struct task_security_struct *tsec = current_security();
3765 struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3766 struct sk_security_struct *sksec;
3767 int err = 0;
3768
3769 isec->sclass = socket_type_to_security_class(family, type, protocol);
3770
3771 if (kern)
3772 isec->sid = SECINITSID_KERNEL;
3773 else {
3774 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3775 if (err)
3776 return err;
3777 }
3778
3779 isec->initialized = 1;
3780
3781 if (sock->sk) {
3782 sksec = sock->sk->sk_security;
3783 sksec->sid = isec->sid;
3784 sksec->sclass = isec->sclass;
3785 err = selinux_netlbl_socket_post_create(sock->sk, family);
3786 }
3787
3788 return err;
3789}
3790
3791/* Range of port numbers used to automatically bind.
3792 Need to determine whether we should perform a name_bind
3793 permission check between the socket and the port number. */
3794
3795static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3796{
3797 struct sock *sk = sock->sk;
3798 u16 family;
3799 int err;
3800
3801 err = sock_has_perm(current, sk, SOCKET__BIND);
3802 if (err)
3803 goto out;
3804
3805 /*
3806 * If PF_INET or PF_INET6, check name_bind permission for the port.
3807 * Multiple address binding for SCTP is not supported yet: we just
3808 * check the first address now.
3809 */
3810 family = sk->sk_family;
3811 if (family == PF_INET || family == PF_INET6) {
3812 char *addrp;
3813 struct sk_security_struct *sksec = sk->sk_security;
3814 struct common_audit_data ad;
3815 struct sockaddr_in *addr4 = NULL;
3816 struct sockaddr_in6 *addr6 = NULL;
3817 unsigned short snum;
3818 u32 sid, node_perm;
3819
3820 if (family == PF_INET) {
3821 addr4 = (struct sockaddr_in *)address;
3822 snum = ntohs(addr4->sin_port);
3823 addrp = (char *)&addr4->sin_addr.s_addr;
3824 } else {
3825 addr6 = (struct sockaddr_in6 *)address;
3826 snum = ntohs(addr6->sin6_port);
3827 addrp = (char *)&addr6->sin6_addr.s6_addr;
3828 }
3829
3830 if (snum) {
3831 int low, high;
3832
3833 inet_get_local_port_range(&low, &high);
3834
3835 if (snum < max(PROT_SOCK, low) || snum > high) {
3836 err = sel_netport_sid(sk->sk_protocol,
3837 snum, &sid);
3838 if (err)
3839 goto out;
3840 COMMON_AUDIT_DATA_INIT(&ad, NET);
3841 ad.u.net.sport = htons(snum);
3842 ad.u.net.family = family;
3843 err = avc_has_perm(sksec->sid, sid,
3844 sksec->sclass,
3845 SOCKET__NAME_BIND, &ad);
3846 if (err)
3847 goto out;
3848 }
3849 }
3850
3851 switch (sksec->sclass) {
3852 case SECCLASS_TCP_SOCKET:
3853 node_perm = TCP_SOCKET__NODE_BIND;
3854 break;
3855
3856 case SECCLASS_UDP_SOCKET:
3857 node_perm = UDP_SOCKET__NODE_BIND;
3858 break;
3859
3860 case SECCLASS_DCCP_SOCKET:
3861 node_perm = DCCP_SOCKET__NODE_BIND;
3862 break;
3863
3864 default:
3865 node_perm = RAWIP_SOCKET__NODE_BIND;
3866 break;
3867 }
3868
3869 err = sel_netnode_sid(addrp, family, &sid);
3870 if (err)
3871 goto out;
3872
3873 COMMON_AUDIT_DATA_INIT(&ad, NET);
3874 ad.u.net.sport = htons(snum);
3875 ad.u.net.family = family;
3876
3877 if (family == PF_INET)
3878 ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3879 else
3880 ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3881
3882 err = avc_has_perm(sksec->sid, sid,
3883 sksec->sclass, node_perm, &ad);
3884 if (err)
3885 goto out;
3886 }
3887out:
3888 return err;
3889}
3890
3891static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3892{
3893 struct sock *sk = sock->sk;
3894 struct sk_security_struct *sksec = sk->sk_security;
3895 int err;
3896
3897 err = sock_has_perm(current, sk, SOCKET__CONNECT);
3898 if (err)
3899 return err;
3900
3901 /*
3902 * If a TCP or DCCP socket, check name_connect permission for the port.
3903 */
3904 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3905 sksec->sclass == SECCLASS_DCCP_SOCKET) {
3906 struct common_audit_data ad;
3907 struct sockaddr_in *addr4 = NULL;
3908 struct sockaddr_in6 *addr6 = NULL;
3909 unsigned short snum;
3910 u32 sid, perm;
3911
3912 if (sk->sk_family == PF_INET) {
3913 addr4 = (struct sockaddr_in *)address;
3914 if (addrlen < sizeof(struct sockaddr_in))
3915 return -EINVAL;
3916 snum = ntohs(addr4->sin_port);
3917 } else {
3918 addr6 = (struct sockaddr_in6 *)address;
3919 if (addrlen < SIN6_LEN_RFC2133)
3920 return -EINVAL;
3921 snum = ntohs(addr6->sin6_port);
3922 }
3923
3924 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3925 if (err)
3926 goto out;
3927
3928 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3929 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3930
3931 COMMON_AUDIT_DATA_INIT(&ad, NET);
3932 ad.u.net.dport = htons(snum);
3933 ad.u.net.family = sk->sk_family;
3934 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3935 if (err)
3936 goto out;
3937 }
3938
3939 err = selinux_netlbl_socket_connect(sk, address);
3940
3941out:
3942 return err;
3943}
3944
3945static int selinux_socket_listen(struct socket *sock, int backlog)
3946{
3947 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3948}
3949
3950static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3951{
3952 int err;
3953 struct inode_security_struct *isec;
3954 struct inode_security_struct *newisec;
3955
3956 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3957 if (err)
3958 return err;
3959
3960 newisec = SOCK_INODE(newsock)->i_security;
3961
3962 isec = SOCK_INODE(sock)->i_security;
3963 newisec->sclass = isec->sclass;
3964 newisec->sid = isec->sid;
3965 newisec->initialized = 1;
3966
3967 return 0;
3968}
3969
3970static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3971 int size)
3972{
3973 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3974}
3975
3976static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3977 int size, int flags)
3978{
3979 return sock_has_perm(current, sock->sk, SOCKET__READ);
3980}
3981
3982static int selinux_socket_getsockname(struct socket *sock)
3983{
3984 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3985}
3986
3987static int selinux_socket_getpeername(struct socket *sock)
3988{
3989 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3990}
3991
3992static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3993{
3994 int err;
3995
3996 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3997 if (err)
3998 return err;
3999
4000 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4001}
4002
4003static int selinux_socket_getsockopt(struct socket *sock, int level,
4004 int optname)
4005{
4006 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4007}
4008
4009static int selinux_socket_shutdown(struct socket *sock, int how)
4010{
4011 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4012}
4013
4014static int selinux_socket_unix_stream_connect(struct sock *sock,
4015 struct sock *other,
4016 struct sock *newsk)
4017{
4018 struct sk_security_struct *sksec_sock = sock->sk_security;
4019 struct sk_security_struct *sksec_other = other->sk_security;
4020 struct sk_security_struct *sksec_new = newsk->sk_security;
4021 struct common_audit_data ad;
4022 int err;
4023
4024 COMMON_AUDIT_DATA_INIT(&ad, NET);
4025 ad.u.net.sk = other;
4026
4027 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4028 sksec_other->sclass,
4029 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4030 if (err)
4031 return err;
4032
4033 /* server child socket */
4034 sksec_new->peer_sid = sksec_sock->sid;
4035 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4036 &sksec_new->sid);
4037 if (err)
4038 return err;
4039
4040 /* connecting socket */
4041 sksec_sock->peer_sid = sksec_new->sid;
4042
4043 return 0;
4044}
4045
4046static int selinux_socket_unix_may_send(struct socket *sock,
4047 struct socket *other)
4048{
4049 struct sk_security_struct *ssec = sock->sk->sk_security;
4050 struct sk_security_struct *osec = other->sk->sk_security;
4051 struct common_audit_data ad;
4052
4053 COMMON_AUDIT_DATA_INIT(&ad, NET);
4054 ad.u.net.sk = other->sk;
4055
4056 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4057 &ad);
4058}
4059
4060static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4061 u32 peer_sid,
4062 struct common_audit_data *ad)
4063{
4064 int err;
4065 u32 if_sid;
4066 u32 node_sid;
4067
4068 err = sel_netif_sid(ifindex, &if_sid);
4069 if (err)
4070 return err;
4071 err = avc_has_perm(peer_sid, if_sid,
4072 SECCLASS_NETIF, NETIF__INGRESS, ad);
4073 if (err)
4074 return err;
4075
4076 err = sel_netnode_sid(addrp, family, &node_sid);
4077 if (err)
4078 return err;
4079 return avc_has_perm(peer_sid, node_sid,
4080 SECCLASS_NODE, NODE__RECVFROM, ad);
4081}
4082
4083static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4084 u16 family)
4085{
4086 int err = 0;
4087 struct sk_security_struct *sksec = sk->sk_security;
4088 u32 sk_sid = sksec->sid;
4089 struct common_audit_data ad;
4090 char *addrp;
4091
4092 COMMON_AUDIT_DATA_INIT(&ad, NET);
4093 ad.u.net.netif = skb->skb_iif;
4094 ad.u.net.family = family;
4095 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4096 if (err)
4097 return err;
4098
4099 if (selinux_secmark_enabled()) {
4100 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4101 PACKET__RECV, &ad);
4102 if (err)
4103 return err;
4104 }
4105
4106 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4107 if (err)
4108 return err;
4109 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4110
4111 return err;
4112}
4113
4114static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4115{
4116 int err;
4117 struct sk_security_struct *sksec = sk->sk_security;
4118 u16 family = sk->sk_family;
4119 u32 sk_sid = sksec->sid;
4120 struct common_audit_data ad;
4121 char *addrp;
4122 u8 secmark_active;
4123 u8 peerlbl_active;
4124
4125 if (family != PF_INET && family != PF_INET6)
4126 return 0;
4127
4128 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4129 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4130 family = PF_INET;
4131
4132 /* If any sort of compatibility mode is enabled then handoff processing
4133 * to the selinux_sock_rcv_skb_compat() function to deal with the
4134 * special handling. We do this in an attempt to keep this function
4135 * as fast and as clean as possible. */
4136 if (!selinux_policycap_netpeer)
4137 return selinux_sock_rcv_skb_compat(sk, skb, family);
4138
4139 secmark_active = selinux_secmark_enabled();
4140 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4141 if (!secmark_active && !peerlbl_active)
4142 return 0;
4143
4144 COMMON_AUDIT_DATA_INIT(&ad, NET);
4145 ad.u.net.netif = skb->skb_iif;
4146 ad.u.net.family = family;
4147 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4148 if (err)
4149 return err;
4150
4151 if (peerlbl_active) {
4152 u32 peer_sid;
4153
4154 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4155 if (err)
4156 return err;
4157 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4158 peer_sid, &ad);
4159 if (err) {
4160 selinux_netlbl_err(skb, err, 0);
4161 return err;
4162 }
4163 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4164 PEER__RECV, &ad);
4165 if (err)
4166 selinux_netlbl_err(skb, err, 0);
4167 }
4168
4169 if (secmark_active) {
4170 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4171 PACKET__RECV, &ad);
4172 if (err)
4173 return err;
4174 }
4175
4176 return err;
4177}
4178
4179static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4180 int __user *optlen, unsigned len)
4181{
4182 int err = 0;
4183 char *scontext;
4184 u32 scontext_len;
4185 struct sk_security_struct *sksec = sock->sk->sk_security;
4186 u32 peer_sid = SECSID_NULL;
4187
4188 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4189 sksec->sclass == SECCLASS_TCP_SOCKET)
4190 peer_sid = sksec->peer_sid;
4191 if (peer_sid == SECSID_NULL)
4192 return -ENOPROTOOPT;
4193
4194 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4195 if (err)
4196 return err;
4197
4198 if (scontext_len > len) {
4199 err = -ERANGE;
4200 goto out_len;
4201 }
4202
4203 if (copy_to_user(optval, scontext, scontext_len))
4204 err = -EFAULT;
4205
4206out_len:
4207 if (put_user(scontext_len, optlen))
4208 err = -EFAULT;
4209 kfree(scontext);
4210 return err;
4211}
4212
4213static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4214{
4215 u32 peer_secid = SECSID_NULL;
4216 u16 family;
4217
4218 if (skb && skb->protocol == htons(ETH_P_IP))
4219 family = PF_INET;
4220 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4221 family = PF_INET6;
4222 else if (sock)
4223 family = sock->sk->sk_family;
4224 else
4225 goto out;
4226
4227 if (sock && family == PF_UNIX)
4228 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4229 else if (skb)
4230 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4231
4232out:
4233 *secid = peer_secid;
4234 if (peer_secid == SECSID_NULL)
4235 return -EINVAL;
4236 return 0;
4237}
4238
4239static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4240{
4241 struct sk_security_struct *sksec;
4242
4243 sksec = kzalloc(sizeof(*sksec), priority);
4244 if (!sksec)
4245 return -ENOMEM;
4246
4247 sksec->peer_sid = SECINITSID_UNLABELED;
4248 sksec->sid = SECINITSID_UNLABELED;
4249 selinux_netlbl_sk_security_reset(sksec);
4250 sk->sk_security = sksec;
4251
4252 return 0;
4253}
4254
4255static void selinux_sk_free_security(struct sock *sk)
4256{
4257 struct sk_security_struct *sksec = sk->sk_security;
4258
4259 sk->sk_security = NULL;
4260 selinux_netlbl_sk_security_free(sksec);
4261 kfree(sksec);
4262}
4263
4264static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4265{
4266 struct sk_security_struct *sksec = sk->sk_security;
4267 struct sk_security_struct *newsksec = newsk->sk_security;
4268
4269 newsksec->sid = sksec->sid;
4270 newsksec->peer_sid = sksec->peer_sid;
4271 newsksec->sclass = sksec->sclass;
4272
4273 selinux_netlbl_sk_security_reset(newsksec);
4274}
4275
4276static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4277{
4278 if (!sk)
4279 *secid = SECINITSID_ANY_SOCKET;
4280 else {
4281 struct sk_security_struct *sksec = sk->sk_security;
4282
4283 *secid = sksec->sid;
4284 }
4285}
4286
4287static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4288{
4289 struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4290 struct sk_security_struct *sksec = sk->sk_security;
4291
4292 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4293 sk->sk_family == PF_UNIX)
4294 isec->sid = sksec->sid;
4295 sksec->sclass = isec->sclass;
4296}
4297
4298static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4299 struct request_sock *req)
4300{
4301 struct sk_security_struct *sksec = sk->sk_security;
4302 int err;
4303 u16 family = sk->sk_family;
4304 u32 newsid;
4305 u32 peersid;
4306
4307 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4308 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4309 family = PF_INET;
4310
4311 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4312 if (err)
4313 return err;
4314 if (peersid == SECSID_NULL) {
4315 req->secid = sksec->sid;
4316 req->peer_secid = SECSID_NULL;
4317 } else {
4318 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4319 if (err)
4320 return err;
4321 req->secid = newsid;
4322 req->peer_secid = peersid;
4323 }
4324
4325 return selinux_netlbl_inet_conn_request(req, family);
4326}
4327
4328static void selinux_inet_csk_clone(struct sock *newsk,
4329 const struct request_sock *req)
4330{
4331 struct sk_security_struct *newsksec = newsk->sk_security;
4332
4333 newsksec->sid = req->secid;
4334 newsksec->peer_sid = req->peer_secid;
4335 /* NOTE: Ideally, we should also get the isec->sid for the
4336 new socket in sync, but we don't have the isec available yet.
4337 So we will wait until sock_graft to do it, by which
4338 time it will have been created and available. */
4339
4340 /* We don't need to take any sort of lock here as we are the only
4341 * thread with access to newsksec */
4342 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4343}
4344
4345static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4346{
4347 u16 family = sk->sk_family;
4348 struct sk_security_struct *sksec = sk->sk_security;
4349
4350 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4351 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4352 family = PF_INET;
4353
4354 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4355}
4356
4357static int selinux_secmark_relabel_packet(u32 sid)
4358{
4359 const struct task_security_struct *__tsec;
4360 u32 tsid;
4361
4362 __tsec = current_security();
4363 tsid = __tsec->sid;
4364
4365 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4366}
4367
4368static void selinux_secmark_refcount_inc(void)
4369{
4370 atomic_inc(&selinux_secmark_refcount);
4371}
4372
4373static void selinux_secmark_refcount_dec(void)
4374{
4375 atomic_dec(&selinux_secmark_refcount);
4376}
4377
4378static void selinux_req_classify_flow(const struct request_sock *req,
4379 struct flowi *fl)
4380{
4381 fl->flowi_secid = req->secid;
4382}
4383
4384static int selinux_tun_dev_create(void)
4385{
4386 u32 sid = current_sid();
4387
4388 /* we aren't taking into account the "sockcreate" SID since the socket
4389 * that is being created here is not a socket in the traditional sense,
4390 * instead it is a private sock, accessible only to the kernel, and
4391 * representing a wide range of network traffic spanning multiple
4392 * connections unlike traditional sockets - check the TUN driver to
4393 * get a better understanding of why this socket is special */
4394
4395 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4396 NULL);
4397}
4398
4399static void selinux_tun_dev_post_create(struct sock *sk)
4400{
4401 struct sk_security_struct *sksec = sk->sk_security;
4402
4403 /* we don't currently perform any NetLabel based labeling here and it
4404 * isn't clear that we would want to do so anyway; while we could apply
4405 * labeling without the support of the TUN user the resulting labeled
4406 * traffic from the other end of the connection would almost certainly
4407 * cause confusion to the TUN user that had no idea network labeling
4408 * protocols were being used */
4409
4410 /* see the comments in selinux_tun_dev_create() about why we don't use
4411 * the sockcreate SID here */
4412
4413 sksec->sid = current_sid();
4414 sksec->sclass = SECCLASS_TUN_SOCKET;
4415}
4416
4417static int selinux_tun_dev_attach(struct sock *sk)
4418{
4419 struct sk_security_struct *sksec = sk->sk_security;
4420 u32 sid = current_sid();
4421 int err;
4422
4423 err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4424 TUN_SOCKET__RELABELFROM, NULL);
4425 if (err)
4426 return err;
4427 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4428 TUN_SOCKET__RELABELTO, NULL);
4429 if (err)
4430 return err;
4431
4432 sksec->sid = sid;
4433
4434 return 0;
4435}
4436
4437static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4438{
4439 int err = 0;
4440 u32 perm;
4441 struct nlmsghdr *nlh;
4442 struct sk_security_struct *sksec = sk->sk_security;
4443
4444 if (skb->len < NLMSG_SPACE(0)) {
4445 err = -EINVAL;
4446 goto out;
4447 }
4448 nlh = nlmsg_hdr(skb);
4449
4450 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4451 if (err) {
4452 if (err == -EINVAL) {
4453 audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4454 "SELinux: unrecognized netlink message"
4455 " type=%hu for sclass=%hu\n",
4456 nlh->nlmsg_type, sksec->sclass);
4457 if (!selinux_enforcing || security_get_allow_unknown())
4458 err = 0;
4459 }
4460
4461 /* Ignore */
4462 if (err == -ENOENT)
4463 err = 0;
4464 goto out;
4465 }
4466
4467 err = sock_has_perm(current, sk, perm);
4468out:
4469 return err;
4470}
4471
4472#ifdef CONFIG_NETFILTER
4473
4474static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4475 u16 family)
4476{
4477 int err;
4478 char *addrp;
4479 u32 peer_sid;
4480 struct common_audit_data ad;
4481 u8 secmark_active;
4482 u8 netlbl_active;
4483 u8 peerlbl_active;
4484
4485 if (!selinux_policycap_netpeer)
4486 return NF_ACCEPT;
4487
4488 secmark_active = selinux_secmark_enabled();
4489 netlbl_active = netlbl_enabled();
4490 peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4491 if (!secmark_active && !peerlbl_active)
4492 return NF_ACCEPT;
4493
4494 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4495 return NF_DROP;
4496
4497 COMMON_AUDIT_DATA_INIT(&ad, NET);
4498 ad.u.net.netif = ifindex;
4499 ad.u.net.family = family;
4500 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4501 return NF_DROP;
4502
4503 if (peerlbl_active) {
4504 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4505 peer_sid, &ad);
4506 if (err) {
4507 selinux_netlbl_err(skb, err, 1);
4508 return NF_DROP;
4509 }
4510 }
4511
4512 if (secmark_active)
4513 if (avc_has_perm(peer_sid, skb->secmark,
4514 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4515 return NF_DROP;
4516
4517 if (netlbl_active)
4518 /* we do this in the FORWARD path and not the POST_ROUTING
4519 * path because we want to make sure we apply the necessary
4520 * labeling before IPsec is applied so we can leverage AH
4521 * protection */
4522 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4523 return NF_DROP;
4524
4525 return NF_ACCEPT;
4526}
4527
4528static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4529 struct sk_buff *skb,
4530 const struct net_device *in,
4531 const struct net_device *out,
4532 int (*okfn)(struct sk_buff *))
4533{
4534 return selinux_ip_forward(skb, in->ifindex, PF_INET);
4535}
4536
4537#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4538static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4539 struct sk_buff *skb,
4540 const struct net_device *in,
4541 const struct net_device *out,
4542 int (*okfn)(struct sk_buff *))
4543{
4544 return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4545}
4546#endif /* IPV6 */
4547
4548static unsigned int selinux_ip_output(struct sk_buff *skb,
4549 u16 family)
4550{
4551 u32 sid;
4552
4553 if (!netlbl_enabled())
4554 return NF_ACCEPT;
4555
4556 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4557 * because we want to make sure we apply the necessary labeling
4558 * before IPsec is applied so we can leverage AH protection */
4559 if (skb->sk) {
4560 struct sk_security_struct *sksec = skb->sk->sk_security;
4561 sid = sksec->sid;
4562 } else
4563 sid = SECINITSID_KERNEL;
4564 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4565 return NF_DROP;
4566
4567 return NF_ACCEPT;
4568}
4569
4570static unsigned int selinux_ipv4_output(unsigned int hooknum,
4571 struct sk_buff *skb,
4572 const struct net_device *in,
4573 const struct net_device *out,
4574 int (*okfn)(struct sk_buff *))
4575{
4576 return selinux_ip_output(skb, PF_INET);
4577}
4578
4579static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4580 int ifindex,
4581 u16 family)
4582{
4583 struct sock *sk = skb->sk;
4584 struct sk_security_struct *sksec;
4585 struct common_audit_data ad;
4586 char *addrp;
4587 u8 proto;
4588
4589 if (sk == NULL)
4590 return NF_ACCEPT;
4591 sksec = sk->sk_security;
4592
4593 COMMON_AUDIT_DATA_INIT(&ad, NET);
4594 ad.u.net.netif = ifindex;
4595 ad.u.net.family = family;
4596 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4597 return NF_DROP;
4598
4599 if (selinux_secmark_enabled())
4600 if (avc_has_perm(sksec->sid, skb->secmark,
4601 SECCLASS_PACKET, PACKET__SEND, &ad))
4602 return NF_DROP_ERR(-ECONNREFUSED);
4603
4604 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4605 return NF_DROP_ERR(-ECONNREFUSED);
4606
4607 return NF_ACCEPT;
4608}
4609
4610static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4611 u16 family)
4612{
4613 u32 secmark_perm;
4614 u32 peer_sid;
4615 struct sock *sk;
4616 struct common_audit_data ad;
4617 char *addrp;
4618 u8 secmark_active;
4619 u8 peerlbl_active;
4620
4621 /* If any sort of compatibility mode is enabled then handoff processing
4622 * to the selinux_ip_postroute_compat() function to deal with the
4623 * special handling. We do this in an attempt to keep this function
4624 * as fast and as clean as possible. */
4625 if (!selinux_policycap_netpeer)
4626 return selinux_ip_postroute_compat(skb, ifindex, family);
4627#ifdef CONFIG_XFRM
4628 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4629 * packet transformation so allow the packet to pass without any checks
4630 * since we'll have another chance to perform access control checks
4631 * when the packet is on it's final way out.
4632 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4633 * is NULL, in this case go ahead and apply access control. */
4634 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4635 return NF_ACCEPT;
4636#endif
4637 secmark_active = selinux_secmark_enabled();
4638 peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4639 if (!secmark_active && !peerlbl_active)
4640 return NF_ACCEPT;
4641
4642 /* if the packet is being forwarded then get the peer label from the
4643 * packet itself; otherwise check to see if it is from a local
4644 * application or the kernel, if from an application get the peer label
4645 * from the sending socket, otherwise use the kernel's sid */
4646 sk = skb->sk;
4647 if (sk == NULL) {
4648 if (skb->skb_iif) {
4649 secmark_perm = PACKET__FORWARD_OUT;
4650 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4651 return NF_DROP;
4652 } else {
4653 secmark_perm = PACKET__SEND;
4654 peer_sid = SECINITSID_KERNEL;
4655 }
4656 } else {
4657 struct sk_security_struct *sksec = sk->sk_security;
4658 peer_sid = sksec->sid;
4659 secmark_perm = PACKET__SEND;
4660 }
4661
4662 COMMON_AUDIT_DATA_INIT(&ad, NET);
4663 ad.u.net.netif = ifindex;
4664 ad.u.net.family = family;
4665 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4666 return NF_DROP;
4667
4668 if (secmark_active)
4669 if (avc_has_perm(peer_sid, skb->secmark,
4670 SECCLASS_PACKET, secmark_perm, &ad))
4671 return NF_DROP_ERR(-ECONNREFUSED);
4672
4673 if (peerlbl_active) {
4674 u32 if_sid;
4675 u32 node_sid;
4676
4677 if (sel_netif_sid(ifindex, &if_sid))
4678 return NF_DROP;
4679 if (avc_has_perm(peer_sid, if_sid,
4680 SECCLASS_NETIF, NETIF__EGRESS, &ad))
4681 return NF_DROP_ERR(-ECONNREFUSED);
4682
4683 if (sel_netnode_sid(addrp, family, &node_sid))
4684 return NF_DROP;
4685 if (avc_has_perm(peer_sid, node_sid,
4686 SECCLASS_NODE, NODE__SENDTO, &ad))
4687 return NF_DROP_ERR(-ECONNREFUSED);
4688 }
4689
4690 return NF_ACCEPT;
4691}
4692
4693static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4694 struct sk_buff *skb,
4695 const struct net_device *in,
4696 const struct net_device *out,
4697 int (*okfn)(struct sk_buff *))
4698{
4699 return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4700}
4701
4702#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4703static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4704 struct sk_buff *skb,
4705 const struct net_device *in,
4706 const struct net_device *out,
4707 int (*okfn)(struct sk_buff *))
4708{
4709 return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4710}
4711#endif /* IPV6 */
4712
4713#endif /* CONFIG_NETFILTER */
4714
4715static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4716{
4717 int err;
4718
4719 err = cap_netlink_send(sk, skb);
4720 if (err)
4721 return err;
4722
4723 return selinux_nlmsg_perm(sk, skb);
4724}
4725
4726static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4727{
4728 int err;
4729 struct common_audit_data ad;
4730 u32 sid;
4731
4732 err = cap_netlink_recv(skb, capability);
4733 if (err)
4734 return err;
4735
4736 COMMON_AUDIT_DATA_INIT(&ad, CAP);
4737 ad.u.cap = capability;
4738
4739 security_task_getsecid(current, &sid);
4740 return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4741 CAP_TO_MASK(capability), &ad);
4742}
4743
4744static int ipc_alloc_security(struct task_struct *task,
4745 struct kern_ipc_perm *perm,
4746 u16 sclass)
4747{
4748 struct ipc_security_struct *isec;
4749 u32 sid;
4750
4751 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4752 if (!isec)
4753 return -ENOMEM;
4754
4755 sid = task_sid(task);
4756 isec->sclass = sclass;
4757 isec->sid = sid;
4758 perm->security = isec;
4759
4760 return 0;
4761}
4762
4763static void ipc_free_security(struct kern_ipc_perm *perm)
4764{
4765 struct ipc_security_struct *isec = perm->security;
4766 perm->security = NULL;
4767 kfree(isec);
4768}
4769
4770static int msg_msg_alloc_security(struct msg_msg *msg)
4771{
4772 struct msg_security_struct *msec;
4773
4774 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4775 if (!msec)
4776 return -ENOMEM;
4777
4778 msec->sid = SECINITSID_UNLABELED;
4779 msg->security = msec;
4780
4781 return 0;
4782}
4783
4784static void msg_msg_free_security(struct msg_msg *msg)
4785{
4786 struct msg_security_struct *msec = msg->security;
4787
4788 msg->security = NULL;
4789 kfree(msec);
4790}
4791
4792static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4793 u32 perms)
4794{
4795 struct ipc_security_struct *isec;
4796 struct common_audit_data ad;
4797 u32 sid = current_sid();
4798
4799 isec = ipc_perms->security;
4800
4801 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4802 ad.u.ipc_id = ipc_perms->key;
4803
4804 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4805}
4806
4807static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4808{
4809 return msg_msg_alloc_security(msg);
4810}
4811
4812static void selinux_msg_msg_free_security(struct msg_msg *msg)
4813{
4814 msg_msg_free_security(msg);
4815}
4816
4817/* message queue security operations */
4818static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4819{
4820 struct ipc_security_struct *isec;
4821 struct common_audit_data ad;
4822 u32 sid = current_sid();
4823 int rc;
4824
4825 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4826 if (rc)
4827 return rc;
4828
4829 isec = msq->q_perm.security;
4830
4831 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832 ad.u.ipc_id = msq->q_perm.key;
4833
4834 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4835 MSGQ__CREATE, &ad);
4836 if (rc) {
4837 ipc_free_security(&msq->q_perm);
4838 return rc;
4839 }
4840 return 0;
4841}
4842
4843static void selinux_msg_queue_free_security(struct msg_queue *msq)
4844{
4845 ipc_free_security(&msq->q_perm);
4846}
4847
4848static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4849{
4850 struct ipc_security_struct *isec;
4851 struct common_audit_data ad;
4852 u32 sid = current_sid();
4853
4854 isec = msq->q_perm.security;
4855
4856 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4857 ad.u.ipc_id = msq->q_perm.key;
4858
4859 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4860 MSGQ__ASSOCIATE, &ad);
4861}
4862
4863static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4864{
4865 int err;
4866 int perms;
4867
4868 switch (cmd) {
4869 case IPC_INFO:
4870 case MSG_INFO:
4871 /* No specific object, just general system-wide information. */
4872 return task_has_system(current, SYSTEM__IPC_INFO);
4873 case IPC_STAT:
4874 case MSG_STAT:
4875 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4876 break;
4877 case IPC_SET:
4878 perms = MSGQ__SETATTR;
4879 break;
4880 case IPC_RMID:
4881 perms = MSGQ__DESTROY;
4882 break;
4883 default:
4884 return 0;
4885 }
4886
4887 err = ipc_has_perm(&msq->q_perm, perms);
4888 return err;
4889}
4890
4891static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4892{
4893 struct ipc_security_struct *isec;
4894 struct msg_security_struct *msec;
4895 struct common_audit_data ad;
4896 u32 sid = current_sid();
4897 int rc;
4898
4899 isec = msq->q_perm.security;
4900 msec = msg->security;
4901
4902 /*
4903 * First time through, need to assign label to the message
4904 */
4905 if (msec->sid == SECINITSID_UNLABELED) {
4906 /*
4907 * Compute new sid based on current process and
4908 * message queue this message will be stored in
4909 */
4910 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4911 NULL, &msec->sid);
4912 if (rc)
4913 return rc;
4914 }
4915
4916 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4917 ad.u.ipc_id = msq->q_perm.key;
4918
4919 /* Can this process write to the queue? */
4920 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4921 MSGQ__WRITE, &ad);
4922 if (!rc)
4923 /* Can this process send the message */
4924 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4925 MSG__SEND, &ad);
4926 if (!rc)
4927 /* Can the message be put in the queue? */
4928 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4929 MSGQ__ENQUEUE, &ad);
4930
4931 return rc;
4932}
4933
4934static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4935 struct task_struct *target,
4936 long type, int mode)
4937{
4938 struct ipc_security_struct *isec;
4939 struct msg_security_struct *msec;
4940 struct common_audit_data ad;
4941 u32 sid = task_sid(target);
4942 int rc;
4943
4944 isec = msq->q_perm.security;
4945 msec = msg->security;
4946
4947 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948 ad.u.ipc_id = msq->q_perm.key;
4949
4950 rc = avc_has_perm(sid, isec->sid,
4951 SECCLASS_MSGQ, MSGQ__READ, &ad);
4952 if (!rc)
4953 rc = avc_has_perm(sid, msec->sid,
4954 SECCLASS_MSG, MSG__RECEIVE, &ad);
4955 return rc;
4956}
4957
4958/* Shared Memory security operations */
4959static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4960{
4961 struct ipc_security_struct *isec;
4962 struct common_audit_data ad;
4963 u32 sid = current_sid();
4964 int rc;
4965
4966 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4967 if (rc)
4968 return rc;
4969
4970 isec = shp->shm_perm.security;
4971
4972 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973 ad.u.ipc_id = shp->shm_perm.key;
4974
4975 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4976 SHM__CREATE, &ad);
4977 if (rc) {
4978 ipc_free_security(&shp->shm_perm);
4979 return rc;
4980 }
4981 return 0;
4982}
4983
4984static void selinux_shm_free_security(struct shmid_kernel *shp)
4985{
4986 ipc_free_security(&shp->shm_perm);
4987}
4988
4989static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4990{
4991 struct ipc_security_struct *isec;
4992 struct common_audit_data ad;
4993 u32 sid = current_sid();
4994
4995 isec = shp->shm_perm.security;
4996
4997 COMMON_AUDIT_DATA_INIT(&ad, IPC);
4998 ad.u.ipc_id = shp->shm_perm.key;
4999
5000 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5001 SHM__ASSOCIATE, &ad);
5002}
5003
5004/* Note, at this point, shp is locked down */
5005static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5006{
5007 int perms;
5008 int err;
5009
5010 switch (cmd) {
5011 case IPC_INFO:
5012 case SHM_INFO:
5013 /* No specific object, just general system-wide information. */
5014 return task_has_system(current, SYSTEM__IPC_INFO);
5015 case IPC_STAT:
5016 case SHM_STAT:
5017 perms = SHM__GETATTR | SHM__ASSOCIATE;
5018 break;
5019 case IPC_SET:
5020 perms = SHM__SETATTR;
5021 break;
5022 case SHM_LOCK:
5023 case SHM_UNLOCK:
5024 perms = SHM__LOCK;
5025 break;
5026 case IPC_RMID:
5027 perms = SHM__DESTROY;
5028 break;
5029 default:
5030 return 0;
5031 }
5032
5033 err = ipc_has_perm(&shp->shm_perm, perms);
5034 return err;
5035}
5036
5037static int selinux_shm_shmat(struct shmid_kernel *shp,
5038 char __user *shmaddr, int shmflg)
5039{
5040 u32 perms;
5041
5042 if (shmflg & SHM_RDONLY)
5043 perms = SHM__READ;
5044 else
5045 perms = SHM__READ | SHM__WRITE;
5046
5047 return ipc_has_perm(&shp->shm_perm, perms);
5048}
5049
5050/* Semaphore security operations */
5051static int selinux_sem_alloc_security(struct sem_array *sma)
5052{
5053 struct ipc_security_struct *isec;
5054 struct common_audit_data ad;
5055 u32 sid = current_sid();
5056 int rc;
5057
5058 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5059 if (rc)
5060 return rc;
5061
5062 isec = sma->sem_perm.security;
5063
5064 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065 ad.u.ipc_id = sma->sem_perm.key;
5066
5067 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5068 SEM__CREATE, &ad);
5069 if (rc) {
5070 ipc_free_security(&sma->sem_perm);
5071 return rc;
5072 }
5073 return 0;
5074}
5075
5076static void selinux_sem_free_security(struct sem_array *sma)
5077{
5078 ipc_free_security(&sma->sem_perm);
5079}
5080
5081static int selinux_sem_associate(struct sem_array *sma, int semflg)
5082{
5083 struct ipc_security_struct *isec;
5084 struct common_audit_data ad;
5085 u32 sid = current_sid();
5086
5087 isec = sma->sem_perm.security;
5088
5089 COMMON_AUDIT_DATA_INIT(&ad, IPC);
5090 ad.u.ipc_id = sma->sem_perm.key;
5091
5092 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5093 SEM__ASSOCIATE, &ad);
5094}
5095
5096/* Note, at this point, sma is locked down */
5097static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5098{
5099 int err;
5100 u32 perms;
5101
5102 switch (cmd) {
5103 case IPC_INFO:
5104 case SEM_INFO:
5105 /* No specific object, just general system-wide information. */
5106 return task_has_system(current, SYSTEM__IPC_INFO);
5107 case GETPID:
5108 case GETNCNT:
5109 case GETZCNT:
5110 perms = SEM__GETATTR;
5111 break;
5112 case GETVAL:
5113 case GETALL:
5114 perms = SEM__READ;
5115 break;
5116 case SETVAL:
5117 case SETALL:
5118 perms = SEM__WRITE;
5119 break;
5120 case IPC_RMID:
5121 perms = SEM__DESTROY;
5122 break;
5123 case IPC_SET:
5124 perms = SEM__SETATTR;
5125 break;
5126 case IPC_STAT:
5127 case SEM_STAT:
5128 perms = SEM__GETATTR | SEM__ASSOCIATE;
5129 break;
5130 default:
5131 return 0;
5132 }
5133
5134 err = ipc_has_perm(&sma->sem_perm, perms);
5135 return err;
5136}
5137
5138static int selinux_sem_semop(struct sem_array *sma,
5139 struct sembuf *sops, unsigned nsops, int alter)
5140{
5141 u32 perms;
5142
5143 if (alter)
5144 perms = SEM__READ | SEM__WRITE;
5145 else
5146 perms = SEM__READ;
5147
5148 return ipc_has_perm(&sma->sem_perm, perms);
5149}
5150
5151static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5152{
5153 u32 av = 0;
5154
5155 av = 0;
5156 if (flag & S_IRUGO)
5157 av |= IPC__UNIX_READ;
5158 if (flag & S_IWUGO)
5159 av |= IPC__UNIX_WRITE;
5160
5161 if (av == 0)
5162 return 0;
5163
5164 return ipc_has_perm(ipcp, av);
5165}
5166
5167static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5168{
5169 struct ipc_security_struct *isec = ipcp->security;
5170 *secid = isec->sid;
5171}
5172
5173static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5174{
5175 if (inode)
5176 inode_doinit_with_dentry(inode, dentry);
5177}
5178
5179static int selinux_getprocattr(struct task_struct *p,
5180 char *name, char **value)
5181{
5182 const struct task_security_struct *__tsec;
5183 u32 sid;
5184 int error;
5185 unsigned len;
5186
5187 if (current != p) {
5188 error = current_has_perm(p, PROCESS__GETATTR);
5189 if (error)
5190 return error;
5191 }
5192
5193 rcu_read_lock();
5194 __tsec = __task_cred(p)->security;
5195
5196 if (!strcmp(name, "current"))
5197 sid = __tsec->sid;
5198 else if (!strcmp(name, "prev"))
5199 sid = __tsec->osid;
5200 else if (!strcmp(name, "exec"))
5201 sid = __tsec->exec_sid;
5202 else if (!strcmp(name, "fscreate"))
5203 sid = __tsec->create_sid;
5204 else if (!strcmp(name, "keycreate"))
5205 sid = __tsec->keycreate_sid;
5206 else if (!strcmp(name, "sockcreate"))
5207 sid = __tsec->sockcreate_sid;
5208 else
5209 goto invalid;
5210 rcu_read_unlock();
5211
5212 if (!sid)
5213 return 0;
5214
5215 error = security_sid_to_context(sid, value, &len);
5216 if (error)
5217 return error;
5218 return len;
5219
5220invalid:
5221 rcu_read_unlock();
5222 return -EINVAL;
5223}
5224
5225static int selinux_setprocattr(struct task_struct *p,
5226 char *name, void *value, size_t size)
5227{
5228 struct task_security_struct *tsec;
5229 struct task_struct *tracer;
5230 struct cred *new;
5231 u32 sid = 0, ptsid;
5232 int error;
5233 char *str = value;
5234
5235 if (current != p) {
5236 /* SELinux only allows a process to change its own
5237 security attributes. */
5238 return -EACCES;
5239 }
5240
5241 /*
5242 * Basic control over ability to set these attributes at all.
5243 * current == p, but we'll pass them separately in case the
5244 * above restriction is ever removed.
5245 */
5246 if (!strcmp(name, "exec"))
5247 error = current_has_perm(p, PROCESS__SETEXEC);
5248 else if (!strcmp(name, "fscreate"))
5249 error = current_has_perm(p, PROCESS__SETFSCREATE);
5250 else if (!strcmp(name, "keycreate"))
5251 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5252 else if (!strcmp(name, "sockcreate"))
5253 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5254 else if (!strcmp(name, "current"))
5255 error = current_has_perm(p, PROCESS__SETCURRENT);
5256 else
5257 error = -EINVAL;
5258 if (error)
5259 return error;
5260
5261 /* Obtain a SID for the context, if one was specified. */
5262 if (size && str[1] && str[1] != '\n') {
5263 if (str[size-1] == '\n') {
5264 str[size-1] = 0;
5265 size--;
5266 }
5267 error = security_context_to_sid(value, size, &sid);
5268 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5269 if (!capable(CAP_MAC_ADMIN))
5270 return error;
5271 error = security_context_to_sid_force(value, size,
5272 &sid);
5273 }
5274 if (error)
5275 return error;
5276 }
5277
5278 new = prepare_creds();
5279 if (!new)
5280 return -ENOMEM;
5281
5282 /* Permission checking based on the specified context is
5283 performed during the actual operation (execve,
5284 open/mkdir/...), when we know the full context of the
5285 operation. See selinux_bprm_set_creds for the execve
5286 checks and may_create for the file creation checks. The
5287 operation will then fail if the context is not permitted. */
5288 tsec = new->security;
5289 if (!strcmp(name, "exec")) {
5290 tsec->exec_sid = sid;
5291 } else if (!strcmp(name, "fscreate")) {
5292 tsec->create_sid = sid;
5293 } else if (!strcmp(name, "keycreate")) {
5294 error = may_create_key(sid, p);
5295 if (error)
5296 goto abort_change;
5297 tsec->keycreate_sid = sid;
5298 } else if (!strcmp(name, "sockcreate")) {
5299 tsec->sockcreate_sid = sid;
5300 } else if (!strcmp(name, "current")) {
5301 error = -EINVAL;
5302 if (sid == 0)
5303 goto abort_change;
5304
5305 /* Only allow single threaded processes to change context */
5306 error = -EPERM;
5307 if (!current_is_single_threaded()) {
5308 error = security_bounded_transition(tsec->sid, sid);
5309 if (error)
5310 goto abort_change;
5311 }
5312
5313 /* Check permissions for the transition. */
5314 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5315 PROCESS__DYNTRANSITION, NULL);
5316 if (error)
5317 goto abort_change;
5318
5319 /* Check for ptracing, and update the task SID if ok.
5320 Otherwise, leave SID unchanged and fail. */
5321 ptsid = 0;
5322 task_lock(p);
5323 tracer = ptrace_parent(p);
5324 if (tracer)
5325 ptsid = task_sid(tracer);
5326 task_unlock(p);
5327
5328 if (tracer) {
5329 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5330 PROCESS__PTRACE, NULL);
5331 if (error)
5332 goto abort_change;
5333 }
5334
5335 tsec->sid = sid;
5336 } else {
5337 error = -EINVAL;
5338 goto abort_change;
5339 }
5340
5341 commit_creds(new);
5342 return size;
5343
5344abort_change:
5345 abort_creds(new);
5346 return error;
5347}
5348
5349static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5350{
5351 return security_sid_to_context(secid, secdata, seclen);
5352}
5353
5354static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5355{
5356 return security_context_to_sid(secdata, seclen, secid);
5357}
5358
5359static void selinux_release_secctx(char *secdata, u32 seclen)
5360{
5361 kfree(secdata);
5362}
5363
5364/*
5365 * called with inode->i_mutex locked
5366 */
5367static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5368{
5369 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5370}
5371
5372/*
5373 * called with inode->i_mutex locked
5374 */
5375static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5376{
5377 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5378}
5379
5380static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5381{
5382 int len = 0;
5383 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5384 ctx, true);
5385 if (len < 0)
5386 return len;
5387 *ctxlen = len;
5388 return 0;
5389}
5390#ifdef CONFIG_KEYS
5391
5392static int selinux_key_alloc(struct key *k, const struct cred *cred,
5393 unsigned long flags)
5394{
5395 const struct task_security_struct *tsec;
5396 struct key_security_struct *ksec;
5397
5398 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5399 if (!ksec)
5400 return -ENOMEM;
5401
5402 tsec = cred->security;
5403 if (tsec->keycreate_sid)
5404 ksec->sid = tsec->keycreate_sid;
5405 else
5406 ksec->sid = tsec->sid;
5407
5408 k->security = ksec;
5409 return 0;
5410}
5411
5412static void selinux_key_free(struct key *k)
5413{
5414 struct key_security_struct *ksec = k->security;
5415
5416 k->security = NULL;
5417 kfree(ksec);
5418}
5419
5420static int selinux_key_permission(key_ref_t key_ref,
5421 const struct cred *cred,
5422 key_perm_t perm)
5423{
5424 struct key *key;
5425 struct key_security_struct *ksec;
5426 u32 sid;
5427
5428 /* if no specific permissions are requested, we skip the
5429 permission check. No serious, additional covert channels
5430 appear to be created. */
5431 if (perm == 0)
5432 return 0;
5433
5434 sid = cred_sid(cred);
5435
5436 key = key_ref_to_ptr(key_ref);
5437 ksec = key->security;
5438
5439 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5440}
5441
5442static int selinux_key_getsecurity(struct key *key, char **_buffer)
5443{
5444 struct key_security_struct *ksec = key->security;
5445 char *context = NULL;
5446 unsigned len;
5447 int rc;
5448
5449 rc = security_sid_to_context(ksec->sid, &context, &len);
5450 if (!rc)
5451 rc = len;
5452 *_buffer = context;
5453 return rc;
5454}
5455
5456#endif
5457
5458static struct security_operations selinux_ops = {
5459 .name = "selinux",
5460
5461 .ptrace_access_check = selinux_ptrace_access_check,
5462 .ptrace_traceme = selinux_ptrace_traceme,
5463 .capget = selinux_capget,
5464 .capset = selinux_capset,
5465 .capable = selinux_capable,
5466 .quotactl = selinux_quotactl,
5467 .quota_on = selinux_quota_on,
5468 .syslog = selinux_syslog,
5469 .vm_enough_memory = selinux_vm_enough_memory,
5470
5471 .netlink_send = selinux_netlink_send,
5472 .netlink_recv = selinux_netlink_recv,
5473
5474 .bprm_set_creds = selinux_bprm_set_creds,
5475 .bprm_committing_creds = selinux_bprm_committing_creds,
5476 .bprm_committed_creds = selinux_bprm_committed_creds,
5477 .bprm_secureexec = selinux_bprm_secureexec,
5478
5479 .sb_alloc_security = selinux_sb_alloc_security,
5480 .sb_free_security = selinux_sb_free_security,
5481 .sb_copy_data = selinux_sb_copy_data,
5482 .sb_remount = selinux_sb_remount,
5483 .sb_kern_mount = selinux_sb_kern_mount,
5484 .sb_show_options = selinux_sb_show_options,
5485 .sb_statfs = selinux_sb_statfs,
5486 .sb_mount = selinux_mount,
5487 .sb_umount = selinux_umount,
5488 .sb_set_mnt_opts = selinux_set_mnt_opts,
5489 .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts,
5490 .sb_parse_opts_str = selinux_parse_opts_str,
5491
5492
5493 .inode_alloc_security = selinux_inode_alloc_security,
5494 .inode_free_security = selinux_inode_free_security,
5495 .inode_init_security = selinux_inode_init_security,
5496 .inode_create = selinux_inode_create,
5497 .inode_link = selinux_inode_link,
5498 .inode_unlink = selinux_inode_unlink,
5499 .inode_symlink = selinux_inode_symlink,
5500 .inode_mkdir = selinux_inode_mkdir,
5501 .inode_rmdir = selinux_inode_rmdir,
5502 .inode_mknod = selinux_inode_mknod,
5503 .inode_rename = selinux_inode_rename,
5504 .inode_readlink = selinux_inode_readlink,
5505 .inode_follow_link = selinux_inode_follow_link,
5506 .inode_permission = selinux_inode_permission,
5507 .inode_setattr = selinux_inode_setattr,
5508 .inode_getattr = selinux_inode_getattr,
5509 .inode_setxattr = selinux_inode_setxattr,
5510 .inode_post_setxattr = selinux_inode_post_setxattr,
5511 .inode_getxattr = selinux_inode_getxattr,
5512 .inode_listxattr = selinux_inode_listxattr,
5513 .inode_removexattr = selinux_inode_removexattr,
5514 .inode_getsecurity = selinux_inode_getsecurity,
5515 .inode_setsecurity = selinux_inode_setsecurity,
5516 .inode_listsecurity = selinux_inode_listsecurity,
5517 .inode_getsecid = selinux_inode_getsecid,
5518
5519 .file_permission = selinux_file_permission,
5520 .file_alloc_security = selinux_file_alloc_security,
5521 .file_free_security = selinux_file_free_security,
5522 .file_ioctl = selinux_file_ioctl,
5523 .file_mmap = selinux_file_mmap,
5524 .file_mprotect = selinux_file_mprotect,
5525 .file_lock = selinux_file_lock,
5526 .file_fcntl = selinux_file_fcntl,
5527 .file_set_fowner = selinux_file_set_fowner,
5528 .file_send_sigiotask = selinux_file_send_sigiotask,
5529 .file_receive = selinux_file_receive,
5530
5531 .dentry_open = selinux_dentry_open,
5532
5533 .task_create = selinux_task_create,
5534 .cred_alloc_blank = selinux_cred_alloc_blank,
5535 .cred_free = selinux_cred_free,
5536 .cred_prepare = selinux_cred_prepare,
5537 .cred_transfer = selinux_cred_transfer,
5538 .kernel_act_as = selinux_kernel_act_as,
5539 .kernel_create_files_as = selinux_kernel_create_files_as,
5540 .kernel_module_request = selinux_kernel_module_request,
5541 .task_setpgid = selinux_task_setpgid,
5542 .task_getpgid = selinux_task_getpgid,
5543 .task_getsid = selinux_task_getsid,
5544 .task_getsecid = selinux_task_getsecid,
5545 .task_setnice = selinux_task_setnice,
5546 .task_setioprio = selinux_task_setioprio,
5547 .task_getioprio = selinux_task_getioprio,
5548 .task_setrlimit = selinux_task_setrlimit,
5549 .task_setscheduler = selinux_task_setscheduler,
5550 .task_getscheduler = selinux_task_getscheduler,
5551 .task_movememory = selinux_task_movememory,
5552 .task_kill = selinux_task_kill,
5553 .task_wait = selinux_task_wait,
5554 .task_to_inode = selinux_task_to_inode,
5555
5556 .ipc_permission = selinux_ipc_permission,
5557 .ipc_getsecid = selinux_ipc_getsecid,
5558
5559 .msg_msg_alloc_security = selinux_msg_msg_alloc_security,
5560 .msg_msg_free_security = selinux_msg_msg_free_security,
5561
5562 .msg_queue_alloc_security = selinux_msg_queue_alloc_security,
5563 .msg_queue_free_security = selinux_msg_queue_free_security,
5564 .msg_queue_associate = selinux_msg_queue_associate,
5565 .msg_queue_msgctl = selinux_msg_queue_msgctl,
5566 .msg_queue_msgsnd = selinux_msg_queue_msgsnd,
5567 .msg_queue_msgrcv = selinux_msg_queue_msgrcv,
5568
5569 .shm_alloc_security = selinux_shm_alloc_security,
5570 .shm_free_security = selinux_shm_free_security,
5571 .shm_associate = selinux_shm_associate,
5572 .shm_shmctl = selinux_shm_shmctl,
5573 .shm_shmat = selinux_shm_shmat,
5574
5575 .sem_alloc_security = selinux_sem_alloc_security,
5576 .sem_free_security = selinux_sem_free_security,
5577 .sem_associate = selinux_sem_associate,
5578 .sem_semctl = selinux_sem_semctl,
5579 .sem_semop = selinux_sem_semop,
5580
5581 .d_instantiate = selinux_d_instantiate,
5582
5583 .getprocattr = selinux_getprocattr,
5584 .setprocattr = selinux_setprocattr,
5585
5586 .secid_to_secctx = selinux_secid_to_secctx,
5587 .secctx_to_secid = selinux_secctx_to_secid,
5588 .release_secctx = selinux_release_secctx,
5589 .inode_notifysecctx = selinux_inode_notifysecctx,
5590 .inode_setsecctx = selinux_inode_setsecctx,
5591 .inode_getsecctx = selinux_inode_getsecctx,
5592
5593 .unix_stream_connect = selinux_socket_unix_stream_connect,
5594 .unix_may_send = selinux_socket_unix_may_send,
5595
5596 .socket_create = selinux_socket_create,
5597 .socket_post_create = selinux_socket_post_create,
5598 .socket_bind = selinux_socket_bind,
5599 .socket_connect = selinux_socket_connect,
5600 .socket_listen = selinux_socket_listen,
5601 .socket_accept = selinux_socket_accept,
5602 .socket_sendmsg = selinux_socket_sendmsg,
5603 .socket_recvmsg = selinux_socket_recvmsg,
5604 .socket_getsockname = selinux_socket_getsockname,
5605 .socket_getpeername = selinux_socket_getpeername,
5606 .socket_getsockopt = selinux_socket_getsockopt,
5607 .socket_setsockopt = selinux_socket_setsockopt,
5608 .socket_shutdown = selinux_socket_shutdown,
5609 .socket_sock_rcv_skb = selinux_socket_sock_rcv_skb,
5610 .socket_getpeersec_stream = selinux_socket_getpeersec_stream,
5611 .socket_getpeersec_dgram = selinux_socket_getpeersec_dgram,
5612 .sk_alloc_security = selinux_sk_alloc_security,
5613 .sk_free_security = selinux_sk_free_security,
5614 .sk_clone_security = selinux_sk_clone_security,
5615 .sk_getsecid = selinux_sk_getsecid,
5616 .sock_graft = selinux_sock_graft,
5617 .inet_conn_request = selinux_inet_conn_request,
5618 .inet_csk_clone = selinux_inet_csk_clone,
5619 .inet_conn_established = selinux_inet_conn_established,
5620 .secmark_relabel_packet = selinux_secmark_relabel_packet,
5621 .secmark_refcount_inc = selinux_secmark_refcount_inc,
5622 .secmark_refcount_dec = selinux_secmark_refcount_dec,
5623 .req_classify_flow = selinux_req_classify_flow,
5624 .tun_dev_create = selinux_tun_dev_create,
5625 .tun_dev_post_create = selinux_tun_dev_post_create,
5626 .tun_dev_attach = selinux_tun_dev_attach,
5627
5628#ifdef CONFIG_SECURITY_NETWORK_XFRM
5629 .xfrm_policy_alloc_security = selinux_xfrm_policy_alloc,
5630 .xfrm_policy_clone_security = selinux_xfrm_policy_clone,
5631 .xfrm_policy_free_security = selinux_xfrm_policy_free,
5632 .xfrm_policy_delete_security = selinux_xfrm_policy_delete,
5633 .xfrm_state_alloc_security = selinux_xfrm_state_alloc,
5634 .xfrm_state_free_security = selinux_xfrm_state_free,
5635 .xfrm_state_delete_security = selinux_xfrm_state_delete,
5636 .xfrm_policy_lookup = selinux_xfrm_policy_lookup,
5637 .xfrm_state_pol_flow_match = selinux_xfrm_state_pol_flow_match,
5638 .xfrm_decode_session = selinux_xfrm_decode_session,
5639#endif
5640
5641#ifdef CONFIG_KEYS
5642 .key_alloc = selinux_key_alloc,
5643 .key_free = selinux_key_free,
5644 .key_permission = selinux_key_permission,
5645 .key_getsecurity = selinux_key_getsecurity,
5646#endif
5647
5648#ifdef CONFIG_AUDIT
5649 .audit_rule_init = selinux_audit_rule_init,
5650 .audit_rule_known = selinux_audit_rule_known,
5651 .audit_rule_match = selinux_audit_rule_match,
5652 .audit_rule_free = selinux_audit_rule_free,
5653#endif
5654};
5655
5656static __init int selinux_init(void)
5657{
5658 if (!security_module_enable(&selinux_ops)) {
5659 selinux_enabled = 0;
5660 return 0;
5661 }
5662
5663 if (!selinux_enabled) {
5664 printk(KERN_INFO "SELinux: Disabled at boot.\n");
5665 return 0;
5666 }
5667
5668 printk(KERN_INFO "SELinux: Initializing.\n");
5669
5670 /* Set the security state for the initial task. */
5671 cred_init_security();
5672
5673 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5674
5675 sel_inode_cache = kmem_cache_create("selinux_inode_security",
5676 sizeof(struct inode_security_struct),
5677 0, SLAB_PANIC, NULL);
5678 avc_init();
5679
5680 if (register_security(&selinux_ops))
5681 panic("SELinux: Unable to register with kernel.\n");
5682
5683 if (selinux_enforcing)
5684 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
5685 else
5686 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
5687
5688 return 0;
5689}
5690
5691static void delayed_superblock_init(struct super_block *sb, void *unused)
5692{
5693 superblock_doinit(sb, NULL);
5694}
5695
5696void selinux_complete_init(void)
5697{
5698 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
5699
5700 /* Set up any superblocks initialized prior to the policy load. */
5701 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
5702 iterate_supers(delayed_superblock_init, NULL);
5703}
5704
5705/* SELinux requires early initialization in order to label
5706 all processes and objects when they are created. */
5707security_initcall(selinux_init);
5708
5709#if defined(CONFIG_NETFILTER)
5710
5711static struct nf_hook_ops selinux_ipv4_ops[] = {
5712 {
5713 .hook = selinux_ipv4_postroute,
5714 .owner = THIS_MODULE,
5715 .pf = PF_INET,
5716 .hooknum = NF_INET_POST_ROUTING,
5717 .priority = NF_IP_PRI_SELINUX_LAST,
5718 },
5719 {
5720 .hook = selinux_ipv4_forward,
5721 .owner = THIS_MODULE,
5722 .pf = PF_INET,
5723 .hooknum = NF_INET_FORWARD,
5724 .priority = NF_IP_PRI_SELINUX_FIRST,
5725 },
5726 {
5727 .hook = selinux_ipv4_output,
5728 .owner = THIS_MODULE,
5729 .pf = PF_INET,
5730 .hooknum = NF_INET_LOCAL_OUT,
5731 .priority = NF_IP_PRI_SELINUX_FIRST,
5732 }
5733};
5734
5735#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5736
5737static struct nf_hook_ops selinux_ipv6_ops[] = {
5738 {
5739 .hook = selinux_ipv6_postroute,
5740 .owner = THIS_MODULE,
5741 .pf = PF_INET6,
5742 .hooknum = NF_INET_POST_ROUTING,
5743 .priority = NF_IP6_PRI_SELINUX_LAST,
5744 },
5745 {
5746 .hook = selinux_ipv6_forward,
5747 .owner = THIS_MODULE,
5748 .pf = PF_INET6,
5749 .hooknum = NF_INET_FORWARD,
5750 .priority = NF_IP6_PRI_SELINUX_FIRST,
5751 }
5752};
5753
5754#endif /* IPV6 */
5755
5756static int __init selinux_nf_ip_init(void)
5757{
5758 int err = 0;
5759
5760 if (!selinux_enabled)
5761 goto out;
5762
5763 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
5764
5765 err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5766 if (err)
5767 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5768
5769#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5770 err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5771 if (err)
5772 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5773#endif /* IPV6 */
5774
5775out:
5776 return err;
5777}
5778
5779__initcall(selinux_nf_ip_init);
5780
5781#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5782static void selinux_nf_ip_exit(void)
5783{
5784 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
5785
5786 nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5787#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5788 nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5789#endif /* IPV6 */
5790}
5791#endif
5792
5793#else /* CONFIG_NETFILTER */
5794
5795#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796#define selinux_nf_ip_exit()
5797#endif
5798
5799#endif /* CONFIG_NETFILTER */
5800
5801#ifdef CONFIG_SECURITY_SELINUX_DISABLE
5802static int selinux_disabled;
5803
5804int selinux_disable(void)
5805{
5806 extern void exit_sel_fs(void);
5807
5808 if (ss_initialized) {
5809 /* Not permitted after initial policy load. */
5810 return -EINVAL;
5811 }
5812
5813 if (selinux_disabled) {
5814 /* Only do this once. */
5815 return -EINVAL;
5816 }
5817
5818 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
5819
5820 selinux_disabled = 1;
5821 selinux_enabled = 0;
5822
5823 reset_security_ops();
5824
5825 /* Try to destroy the avc node cache */
5826 avc_disable();
5827
5828 /* Unregister netfilter hooks. */
5829 selinux_nf_ip_exit();
5830
5831 /* Unregister selinuxfs. */
5832 exit_sel_fs();
5833
5834 return 0;
5835}
5836#endif
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/lsm_hooks.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/tcp.h> /* struct or_callable used in sock_rcv_skb */
55#include <net/inet_connection_sock.h>
56#include <net/net_namespace.h>
57#include <net/netlabel.h>
58#include <linux/uaccess.h>
59#include <asm/ioctls.h>
60#include <linux/atomic.h>
61#include <linux/bitops.h>
62#include <linux/interrupt.h>
63#include <linux/netdevice.h> /* for network interface checks */
64#include <net/netlink.h>
65#include <linux/tcp.h>
66#include <linux/udp.h>
67#include <linux/dccp.h>
68#include <linux/quota.h>
69#include <linux/un.h> /* for Unix socket types */
70#include <net/af_unix.h> /* for Unix socket types */
71#include <linux/parser.h>
72#include <linux/nfs_mount.h>
73#include <net/ipv6.h>
74#include <linux/hugetlb.h>
75#include <linux/personality.h>
76#include <linux/audit.h>
77#include <linux/string.h>
78#include <linux/selinux.h>
79#include <linux/mutex.h>
80#include <linux/posix-timers.h>
81#include <linux/syslog.h>
82#include <linux/user_namespace.h>
83#include <linux/export.h>
84#include <linux/msg.h>
85#include <linux/shm.h>
86
87#include "avc.h"
88#include "objsec.h"
89#include "netif.h"
90#include "netnode.h"
91#include "netport.h"
92#include "xfrm.h"
93#include "netlabel.h"
94#include "audit.h"
95#include "avc_ss.h"
96
97/* SECMARK reference count */
98static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
99
100#ifdef CONFIG_SECURITY_SELINUX_DEVELOP
101int selinux_enforcing;
102
103static int __init enforcing_setup(char *str)
104{
105 unsigned long enforcing;
106 if (!kstrtoul(str, 0, &enforcing))
107 selinux_enforcing = enforcing ? 1 : 0;
108 return 1;
109}
110__setup("enforcing=", enforcing_setup);
111#endif
112
113#ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
114int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
115
116static int __init selinux_enabled_setup(char *str)
117{
118 unsigned long enabled;
119 if (!kstrtoul(str, 0, &enabled))
120 selinux_enabled = enabled ? 1 : 0;
121 return 1;
122}
123__setup("selinux=", selinux_enabled_setup);
124#else
125int selinux_enabled = 1;
126#endif
127
128static struct kmem_cache *sel_inode_cache;
129static struct kmem_cache *file_security_cache;
130
131/**
132 * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
133 *
134 * Description:
135 * This function checks the SECMARK reference counter to see if any SECMARK
136 * targets are currently configured, if the reference counter is greater than
137 * zero SECMARK is considered to be enabled. Returns true (1) if SECMARK is
138 * enabled, false (0) if SECMARK is disabled. If the always_check_network
139 * policy capability is enabled, SECMARK is always considered enabled.
140 *
141 */
142static int selinux_secmark_enabled(void)
143{
144 return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
145}
146
147/**
148 * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
149 *
150 * Description:
151 * This function checks if NetLabel or labeled IPSEC is enabled. Returns true
152 * (1) if any are enabled or false (0) if neither are enabled. If the
153 * always_check_network policy capability is enabled, peer labeling
154 * is always considered enabled.
155 *
156 */
157static int selinux_peerlbl_enabled(void)
158{
159 return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
160}
161
162static int selinux_netcache_avc_callback(u32 event)
163{
164 if (event == AVC_CALLBACK_RESET) {
165 sel_netif_flush();
166 sel_netnode_flush();
167 sel_netport_flush();
168 synchronize_net();
169 }
170 return 0;
171}
172
173/*
174 * initialise the security for the init task
175 */
176static void cred_init_security(void)
177{
178 struct cred *cred = (struct cred *) current->real_cred;
179 struct task_security_struct *tsec;
180
181 tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
182 if (!tsec)
183 panic("SELinux: Failed to initialize initial task.\n");
184
185 tsec->osid = tsec->sid = SECINITSID_KERNEL;
186 cred->security = tsec;
187}
188
189/*
190 * get the security ID of a set of credentials
191 */
192static inline u32 cred_sid(const struct cred *cred)
193{
194 const struct task_security_struct *tsec;
195
196 tsec = cred->security;
197 return tsec->sid;
198}
199
200/*
201 * get the objective security ID of a task
202 */
203static inline u32 task_sid(const struct task_struct *task)
204{
205 u32 sid;
206
207 rcu_read_lock();
208 sid = cred_sid(__task_cred(task));
209 rcu_read_unlock();
210 return sid;
211}
212
213/*
214 * get the subjective security ID of the current task
215 */
216static inline u32 current_sid(void)
217{
218 const struct task_security_struct *tsec = current_security();
219
220 return tsec->sid;
221}
222
223/* Allocate and free functions for each kind of security blob. */
224
225static int inode_alloc_security(struct inode *inode)
226{
227 struct inode_security_struct *isec;
228 u32 sid = current_sid();
229
230 isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
231 if (!isec)
232 return -ENOMEM;
233
234 spin_lock_init(&isec->lock);
235 INIT_LIST_HEAD(&isec->list);
236 isec->inode = inode;
237 isec->sid = SECINITSID_UNLABELED;
238 isec->sclass = SECCLASS_FILE;
239 isec->task_sid = sid;
240 isec->initialized = LABEL_INVALID;
241 inode->i_security = isec;
242
243 return 0;
244}
245
246static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
247
248/*
249 * Try reloading inode security labels that have been marked as invalid. The
250 * @may_sleep parameter indicates when sleeping and thus reloading labels is
251 * allowed; when set to false, returns -ECHILD when the label is
252 * invalid. The @opt_dentry parameter should be set to a dentry of the inode;
253 * when no dentry is available, set it to NULL instead.
254 */
255static int __inode_security_revalidate(struct inode *inode,
256 struct dentry *opt_dentry,
257 bool may_sleep)
258{
259 struct inode_security_struct *isec = inode->i_security;
260
261 might_sleep_if(may_sleep);
262
263 if (ss_initialized && isec->initialized != LABEL_INITIALIZED) {
264 if (!may_sleep)
265 return -ECHILD;
266
267 /*
268 * Try reloading the inode security label. This will fail if
269 * @opt_dentry is NULL and no dentry for this inode can be
270 * found; in that case, continue using the old label.
271 */
272 inode_doinit_with_dentry(inode, opt_dentry);
273 }
274 return 0;
275}
276
277static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
278{
279 return inode->i_security;
280}
281
282static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
283{
284 int error;
285
286 error = __inode_security_revalidate(inode, NULL, !rcu);
287 if (error)
288 return ERR_PTR(error);
289 return inode->i_security;
290}
291
292/*
293 * Get the security label of an inode.
294 */
295static struct inode_security_struct *inode_security(struct inode *inode)
296{
297 __inode_security_revalidate(inode, NULL, true);
298 return inode->i_security;
299}
300
301static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
302{
303 struct inode *inode = d_backing_inode(dentry);
304
305 return inode->i_security;
306}
307
308/*
309 * Get the security label of a dentry's backing inode.
310 */
311static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
312{
313 struct inode *inode = d_backing_inode(dentry);
314
315 __inode_security_revalidate(inode, dentry, true);
316 return inode->i_security;
317}
318
319static void inode_free_rcu(struct rcu_head *head)
320{
321 struct inode_security_struct *isec;
322
323 isec = container_of(head, struct inode_security_struct, rcu);
324 kmem_cache_free(sel_inode_cache, isec);
325}
326
327static void inode_free_security(struct inode *inode)
328{
329 struct inode_security_struct *isec = inode->i_security;
330 struct superblock_security_struct *sbsec = inode->i_sb->s_security;
331
332 /*
333 * As not all inode security structures are in a list, we check for
334 * empty list outside of the lock to make sure that we won't waste
335 * time taking a lock doing nothing.
336 *
337 * The list_del_init() function can be safely called more than once.
338 * It should not be possible for this function to be called with
339 * concurrent list_add(), but for better safety against future changes
340 * in the code, we use list_empty_careful() here.
341 */
342 if (!list_empty_careful(&isec->list)) {
343 spin_lock(&sbsec->isec_lock);
344 list_del_init(&isec->list);
345 spin_unlock(&sbsec->isec_lock);
346 }
347
348 /*
349 * The inode may still be referenced in a path walk and
350 * a call to selinux_inode_permission() can be made
351 * after inode_free_security() is called. Ideally, the VFS
352 * wouldn't do this, but fixing that is a much harder
353 * job. For now, simply free the i_security via RCU, and
354 * leave the current inode->i_security pointer intact.
355 * The inode will be freed after the RCU grace period too.
356 */
357 call_rcu(&isec->rcu, inode_free_rcu);
358}
359
360static int file_alloc_security(struct file *file)
361{
362 struct file_security_struct *fsec;
363 u32 sid = current_sid();
364
365 fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
366 if (!fsec)
367 return -ENOMEM;
368
369 fsec->sid = sid;
370 fsec->fown_sid = sid;
371 file->f_security = fsec;
372
373 return 0;
374}
375
376static void file_free_security(struct file *file)
377{
378 struct file_security_struct *fsec = file->f_security;
379 file->f_security = NULL;
380 kmem_cache_free(file_security_cache, fsec);
381}
382
383static int superblock_alloc_security(struct super_block *sb)
384{
385 struct superblock_security_struct *sbsec;
386
387 sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
388 if (!sbsec)
389 return -ENOMEM;
390
391 mutex_init(&sbsec->lock);
392 INIT_LIST_HEAD(&sbsec->isec_head);
393 spin_lock_init(&sbsec->isec_lock);
394 sbsec->sb = sb;
395 sbsec->sid = SECINITSID_UNLABELED;
396 sbsec->def_sid = SECINITSID_FILE;
397 sbsec->mntpoint_sid = SECINITSID_UNLABELED;
398 sb->s_security = sbsec;
399
400 return 0;
401}
402
403static void superblock_free_security(struct super_block *sb)
404{
405 struct superblock_security_struct *sbsec = sb->s_security;
406 sb->s_security = NULL;
407 kfree(sbsec);
408}
409
410/* The file system's label must be initialized prior to use. */
411
412static const char *labeling_behaviors[7] = {
413 "uses xattr",
414 "uses transition SIDs",
415 "uses task SIDs",
416 "uses genfs_contexts",
417 "not configured for labeling",
418 "uses mountpoint labeling",
419 "uses native labeling",
420};
421
422static inline int inode_doinit(struct inode *inode)
423{
424 return inode_doinit_with_dentry(inode, NULL);
425}
426
427enum {
428 Opt_error = -1,
429 Opt_context = 1,
430 Opt_fscontext = 2,
431 Opt_defcontext = 3,
432 Opt_rootcontext = 4,
433 Opt_labelsupport = 5,
434 Opt_nextmntopt = 6,
435};
436
437#define NUM_SEL_MNT_OPTS (Opt_nextmntopt - 1)
438
439static const match_table_t tokens = {
440 {Opt_context, CONTEXT_STR "%s"},
441 {Opt_fscontext, FSCONTEXT_STR "%s"},
442 {Opt_defcontext, DEFCONTEXT_STR "%s"},
443 {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
444 {Opt_labelsupport, LABELSUPP_STR},
445 {Opt_error, NULL},
446};
447
448#define SEL_MOUNT_FAIL_MSG "SELinux: duplicate or incompatible mount options\n"
449
450static int may_context_mount_sb_relabel(u32 sid,
451 struct superblock_security_struct *sbsec,
452 const struct cred *cred)
453{
454 const struct task_security_struct *tsec = cred->security;
455 int rc;
456
457 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
458 FILESYSTEM__RELABELFROM, NULL);
459 if (rc)
460 return rc;
461
462 rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
463 FILESYSTEM__RELABELTO, NULL);
464 return rc;
465}
466
467static int may_context_mount_inode_relabel(u32 sid,
468 struct superblock_security_struct *sbsec,
469 const struct cred *cred)
470{
471 const struct task_security_struct *tsec = cred->security;
472 int rc;
473 rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
474 FILESYSTEM__RELABELFROM, NULL);
475 if (rc)
476 return rc;
477
478 rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
479 FILESYSTEM__ASSOCIATE, NULL);
480 return rc;
481}
482
483static int selinux_is_sblabel_mnt(struct super_block *sb)
484{
485 struct superblock_security_struct *sbsec = sb->s_security;
486
487 return sbsec->behavior == SECURITY_FS_USE_XATTR ||
488 sbsec->behavior == SECURITY_FS_USE_TRANS ||
489 sbsec->behavior == SECURITY_FS_USE_TASK ||
490 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
491 /* Special handling. Genfs but also in-core setxattr handler */
492 !strcmp(sb->s_type->name, "sysfs") ||
493 !strcmp(sb->s_type->name, "pstore") ||
494 !strcmp(sb->s_type->name, "debugfs") ||
495 !strcmp(sb->s_type->name, "rootfs");
496}
497
498static int sb_finish_set_opts(struct super_block *sb)
499{
500 struct superblock_security_struct *sbsec = sb->s_security;
501 struct dentry *root = sb->s_root;
502 struct inode *root_inode = d_backing_inode(root);
503 int rc = 0;
504
505 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
506 /* Make sure that the xattr handler exists and that no
507 error other than -ENODATA is returned by getxattr on
508 the root directory. -ENODATA is ok, as this may be
509 the first boot of the SELinux kernel before we have
510 assigned xattr values to the filesystem. */
511 if (!(root_inode->i_opflags & IOP_XATTR)) {
512 printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
513 "xattr support\n", sb->s_id, sb->s_type->name);
514 rc = -EOPNOTSUPP;
515 goto out;
516 }
517
518 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
519 if (rc < 0 && rc != -ENODATA) {
520 if (rc == -EOPNOTSUPP)
521 printk(KERN_WARNING "SELinux: (dev %s, type "
522 "%s) has no security xattr handler\n",
523 sb->s_id, sb->s_type->name);
524 else
525 printk(KERN_WARNING "SELinux: (dev %s, type "
526 "%s) getxattr errno %d\n", sb->s_id,
527 sb->s_type->name, -rc);
528 goto out;
529 }
530 }
531
532 if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
533 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
534 sb->s_id, sb->s_type->name);
535
536 sbsec->flags |= SE_SBINITIALIZED;
537 if (selinux_is_sblabel_mnt(sb))
538 sbsec->flags |= SBLABEL_MNT;
539
540 /* Initialize the root inode. */
541 rc = inode_doinit_with_dentry(root_inode, root);
542
543 /* Initialize any other inodes associated with the superblock, e.g.
544 inodes created prior to initial policy load or inodes created
545 during get_sb by a pseudo filesystem that directly
546 populates itself. */
547 spin_lock(&sbsec->isec_lock);
548next_inode:
549 if (!list_empty(&sbsec->isec_head)) {
550 struct inode_security_struct *isec =
551 list_entry(sbsec->isec_head.next,
552 struct inode_security_struct, list);
553 struct inode *inode = isec->inode;
554 list_del_init(&isec->list);
555 spin_unlock(&sbsec->isec_lock);
556 inode = igrab(inode);
557 if (inode) {
558 if (!IS_PRIVATE(inode))
559 inode_doinit(inode);
560 iput(inode);
561 }
562 spin_lock(&sbsec->isec_lock);
563 goto next_inode;
564 }
565 spin_unlock(&sbsec->isec_lock);
566out:
567 return rc;
568}
569
570/*
571 * This function should allow an FS to ask what it's mount security
572 * options were so it can use those later for submounts, displaying
573 * mount options, or whatever.
574 */
575static int selinux_get_mnt_opts(const struct super_block *sb,
576 struct security_mnt_opts *opts)
577{
578 int rc = 0, i;
579 struct superblock_security_struct *sbsec = sb->s_security;
580 char *context = NULL;
581 u32 len;
582 char tmp;
583
584 security_init_mnt_opts(opts);
585
586 if (!(sbsec->flags & SE_SBINITIALIZED))
587 return -EINVAL;
588
589 if (!ss_initialized)
590 return -EINVAL;
591
592 /* make sure we always check enough bits to cover the mask */
593 BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
594
595 tmp = sbsec->flags & SE_MNTMASK;
596 /* count the number of mount options for this sb */
597 for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
598 if (tmp & 0x01)
599 opts->num_mnt_opts++;
600 tmp >>= 1;
601 }
602 /* Check if the Label support flag is set */
603 if (sbsec->flags & SBLABEL_MNT)
604 opts->num_mnt_opts++;
605
606 opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
607 if (!opts->mnt_opts) {
608 rc = -ENOMEM;
609 goto out_free;
610 }
611
612 opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
613 if (!opts->mnt_opts_flags) {
614 rc = -ENOMEM;
615 goto out_free;
616 }
617
618 i = 0;
619 if (sbsec->flags & FSCONTEXT_MNT) {
620 rc = security_sid_to_context(sbsec->sid, &context, &len);
621 if (rc)
622 goto out_free;
623 opts->mnt_opts[i] = context;
624 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
625 }
626 if (sbsec->flags & CONTEXT_MNT) {
627 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
628 if (rc)
629 goto out_free;
630 opts->mnt_opts[i] = context;
631 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
632 }
633 if (sbsec->flags & DEFCONTEXT_MNT) {
634 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
635 if (rc)
636 goto out_free;
637 opts->mnt_opts[i] = context;
638 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
639 }
640 if (sbsec->flags & ROOTCONTEXT_MNT) {
641 struct dentry *root = sbsec->sb->s_root;
642 struct inode_security_struct *isec = backing_inode_security(root);
643
644 rc = security_sid_to_context(isec->sid, &context, &len);
645 if (rc)
646 goto out_free;
647 opts->mnt_opts[i] = context;
648 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
649 }
650 if (sbsec->flags & SBLABEL_MNT) {
651 opts->mnt_opts[i] = NULL;
652 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
653 }
654
655 BUG_ON(i != opts->num_mnt_opts);
656
657 return 0;
658
659out_free:
660 security_free_mnt_opts(opts);
661 return rc;
662}
663
664static int bad_option(struct superblock_security_struct *sbsec, char flag,
665 u32 old_sid, u32 new_sid)
666{
667 char mnt_flags = sbsec->flags & SE_MNTMASK;
668
669 /* check if the old mount command had the same options */
670 if (sbsec->flags & SE_SBINITIALIZED)
671 if (!(sbsec->flags & flag) ||
672 (old_sid != new_sid))
673 return 1;
674
675 /* check if we were passed the same options twice,
676 * aka someone passed context=a,context=b
677 */
678 if (!(sbsec->flags & SE_SBINITIALIZED))
679 if (mnt_flags & flag)
680 return 1;
681 return 0;
682}
683
684/*
685 * Allow filesystems with binary mount data to explicitly set mount point
686 * labeling information.
687 */
688static int selinux_set_mnt_opts(struct super_block *sb,
689 struct security_mnt_opts *opts,
690 unsigned long kern_flags,
691 unsigned long *set_kern_flags)
692{
693 const struct cred *cred = current_cred();
694 int rc = 0, i;
695 struct superblock_security_struct *sbsec = sb->s_security;
696 const char *name = sb->s_type->name;
697 struct dentry *root = sbsec->sb->s_root;
698 struct inode_security_struct *root_isec;
699 u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
700 u32 defcontext_sid = 0;
701 char **mount_options = opts->mnt_opts;
702 int *flags = opts->mnt_opts_flags;
703 int num_opts = opts->num_mnt_opts;
704
705 mutex_lock(&sbsec->lock);
706
707 if (!ss_initialized) {
708 if (!num_opts) {
709 /* Defer initialization until selinux_complete_init,
710 after the initial policy is loaded and the security
711 server is ready to handle calls. */
712 goto out;
713 }
714 rc = -EINVAL;
715 printk(KERN_WARNING "SELinux: Unable to set superblock options "
716 "before the security server is initialized\n");
717 goto out;
718 }
719 if (kern_flags && !set_kern_flags) {
720 /* Specifying internal flags without providing a place to
721 * place the results is not allowed */
722 rc = -EINVAL;
723 goto out;
724 }
725
726 /*
727 * Binary mount data FS will come through this function twice. Once
728 * from an explicit call and once from the generic calls from the vfs.
729 * Since the generic VFS calls will not contain any security mount data
730 * we need to skip the double mount verification.
731 *
732 * This does open a hole in which we will not notice if the first
733 * mount using this sb set explict options and a second mount using
734 * this sb does not set any security options. (The first options
735 * will be used for both mounts)
736 */
737 if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
738 && (num_opts == 0))
739 goto out;
740
741 root_isec = backing_inode_security_novalidate(root);
742
743 /*
744 * parse the mount options, check if they are valid sids.
745 * also check if someone is trying to mount the same sb more
746 * than once with different security options.
747 */
748 for (i = 0; i < num_opts; i++) {
749 u32 sid;
750
751 if (flags[i] == SBLABEL_MNT)
752 continue;
753 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
754 if (rc) {
755 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
756 "(%s) failed for (dev %s, type %s) errno=%d\n",
757 mount_options[i], sb->s_id, name, rc);
758 goto out;
759 }
760 switch (flags[i]) {
761 case FSCONTEXT_MNT:
762 fscontext_sid = sid;
763
764 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
765 fscontext_sid))
766 goto out_double_mount;
767
768 sbsec->flags |= FSCONTEXT_MNT;
769 break;
770 case CONTEXT_MNT:
771 context_sid = sid;
772
773 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
774 context_sid))
775 goto out_double_mount;
776
777 sbsec->flags |= CONTEXT_MNT;
778 break;
779 case ROOTCONTEXT_MNT:
780 rootcontext_sid = sid;
781
782 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
783 rootcontext_sid))
784 goto out_double_mount;
785
786 sbsec->flags |= ROOTCONTEXT_MNT;
787
788 break;
789 case DEFCONTEXT_MNT:
790 defcontext_sid = sid;
791
792 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
793 defcontext_sid))
794 goto out_double_mount;
795
796 sbsec->flags |= DEFCONTEXT_MNT;
797
798 break;
799 default:
800 rc = -EINVAL;
801 goto out;
802 }
803 }
804
805 if (sbsec->flags & SE_SBINITIALIZED) {
806 /* previously mounted with options, but not on this attempt? */
807 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
808 goto out_double_mount;
809 rc = 0;
810 goto out;
811 }
812
813 if (strcmp(sb->s_type->name, "proc") == 0)
814 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
815
816 if (!strcmp(sb->s_type->name, "debugfs") ||
817 !strcmp(sb->s_type->name, "sysfs") ||
818 !strcmp(sb->s_type->name, "pstore"))
819 sbsec->flags |= SE_SBGENFS;
820
821 if (!sbsec->behavior) {
822 /*
823 * Determine the labeling behavior to use for this
824 * filesystem type.
825 */
826 rc = security_fs_use(sb);
827 if (rc) {
828 printk(KERN_WARNING
829 "%s: security_fs_use(%s) returned %d\n",
830 __func__, sb->s_type->name, rc);
831 goto out;
832 }
833 }
834
835 /*
836 * If this is a user namespace mount, no contexts are allowed
837 * on the command line and security labels must be ignored.
838 */
839 if (sb->s_user_ns != &init_user_ns) {
840 if (context_sid || fscontext_sid || rootcontext_sid ||
841 defcontext_sid) {
842 rc = -EACCES;
843 goto out;
844 }
845 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
846 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
847 rc = security_transition_sid(current_sid(), current_sid(),
848 SECCLASS_FILE, NULL,
849 &sbsec->mntpoint_sid);
850 if (rc)
851 goto out;
852 }
853 goto out_set_opts;
854 }
855
856 /* sets the context of the superblock for the fs being mounted. */
857 if (fscontext_sid) {
858 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
859 if (rc)
860 goto out;
861
862 sbsec->sid = fscontext_sid;
863 }
864
865 /*
866 * Switch to using mount point labeling behavior.
867 * sets the label used on all file below the mountpoint, and will set
868 * the superblock context if not already set.
869 */
870 if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
871 sbsec->behavior = SECURITY_FS_USE_NATIVE;
872 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
873 }
874
875 if (context_sid) {
876 if (!fscontext_sid) {
877 rc = may_context_mount_sb_relabel(context_sid, sbsec,
878 cred);
879 if (rc)
880 goto out;
881 sbsec->sid = context_sid;
882 } else {
883 rc = may_context_mount_inode_relabel(context_sid, sbsec,
884 cred);
885 if (rc)
886 goto out;
887 }
888 if (!rootcontext_sid)
889 rootcontext_sid = context_sid;
890
891 sbsec->mntpoint_sid = context_sid;
892 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
893 }
894
895 if (rootcontext_sid) {
896 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
897 cred);
898 if (rc)
899 goto out;
900
901 root_isec->sid = rootcontext_sid;
902 root_isec->initialized = LABEL_INITIALIZED;
903 }
904
905 if (defcontext_sid) {
906 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
907 sbsec->behavior != SECURITY_FS_USE_NATIVE) {
908 rc = -EINVAL;
909 printk(KERN_WARNING "SELinux: defcontext option is "
910 "invalid for this filesystem type\n");
911 goto out;
912 }
913
914 if (defcontext_sid != sbsec->def_sid) {
915 rc = may_context_mount_inode_relabel(defcontext_sid,
916 sbsec, cred);
917 if (rc)
918 goto out;
919 }
920
921 sbsec->def_sid = defcontext_sid;
922 }
923
924out_set_opts:
925 rc = sb_finish_set_opts(sb);
926out:
927 mutex_unlock(&sbsec->lock);
928 return rc;
929out_double_mount:
930 rc = -EINVAL;
931 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, different "
932 "security settings for (dev %s, type %s)\n", sb->s_id, name);
933 goto out;
934}
935
936static int selinux_cmp_sb_context(const struct super_block *oldsb,
937 const struct super_block *newsb)
938{
939 struct superblock_security_struct *old = oldsb->s_security;
940 struct superblock_security_struct *new = newsb->s_security;
941 char oldflags = old->flags & SE_MNTMASK;
942 char newflags = new->flags & SE_MNTMASK;
943
944 if (oldflags != newflags)
945 goto mismatch;
946 if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
947 goto mismatch;
948 if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
949 goto mismatch;
950 if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
951 goto mismatch;
952 if (oldflags & ROOTCONTEXT_MNT) {
953 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
954 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
955 if (oldroot->sid != newroot->sid)
956 goto mismatch;
957 }
958 return 0;
959mismatch:
960 printk(KERN_WARNING "SELinux: mount invalid. Same superblock, "
961 "different security settings for (dev %s, "
962 "type %s)\n", newsb->s_id, newsb->s_type->name);
963 return -EBUSY;
964}
965
966static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
967 struct super_block *newsb)
968{
969 const struct superblock_security_struct *oldsbsec = oldsb->s_security;
970 struct superblock_security_struct *newsbsec = newsb->s_security;
971
972 int set_fscontext = (oldsbsec->flags & FSCONTEXT_MNT);
973 int set_context = (oldsbsec->flags & CONTEXT_MNT);
974 int set_rootcontext = (oldsbsec->flags & ROOTCONTEXT_MNT);
975
976 /*
977 * if the parent was able to be mounted it clearly had no special lsm
978 * mount options. thus we can safely deal with this superblock later
979 */
980 if (!ss_initialized)
981 return 0;
982
983 /* how can we clone if the old one wasn't set up?? */
984 BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
985
986 /* if fs is reusing a sb, make sure that the contexts match */
987 if (newsbsec->flags & SE_SBINITIALIZED)
988 return selinux_cmp_sb_context(oldsb, newsb);
989
990 mutex_lock(&newsbsec->lock);
991
992 newsbsec->flags = oldsbsec->flags;
993
994 newsbsec->sid = oldsbsec->sid;
995 newsbsec->def_sid = oldsbsec->def_sid;
996 newsbsec->behavior = oldsbsec->behavior;
997
998 if (set_context) {
999 u32 sid = oldsbsec->mntpoint_sid;
1000
1001 if (!set_fscontext)
1002 newsbsec->sid = sid;
1003 if (!set_rootcontext) {
1004 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1005 newisec->sid = sid;
1006 }
1007 newsbsec->mntpoint_sid = sid;
1008 }
1009 if (set_rootcontext) {
1010 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1011 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1012
1013 newisec->sid = oldisec->sid;
1014 }
1015
1016 sb_finish_set_opts(newsb);
1017 mutex_unlock(&newsbsec->lock);
1018 return 0;
1019}
1020
1021static int selinux_parse_opts_str(char *options,
1022 struct security_mnt_opts *opts)
1023{
1024 char *p;
1025 char *context = NULL, *defcontext = NULL;
1026 char *fscontext = NULL, *rootcontext = NULL;
1027 int rc, num_mnt_opts = 0;
1028
1029 opts->num_mnt_opts = 0;
1030
1031 /* Standard string-based options. */
1032 while ((p = strsep(&options, "|")) != NULL) {
1033 int token;
1034 substring_t args[MAX_OPT_ARGS];
1035
1036 if (!*p)
1037 continue;
1038
1039 token = match_token(p, tokens, args);
1040
1041 switch (token) {
1042 case Opt_context:
1043 if (context || defcontext) {
1044 rc = -EINVAL;
1045 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1046 goto out_err;
1047 }
1048 context = match_strdup(&args[0]);
1049 if (!context) {
1050 rc = -ENOMEM;
1051 goto out_err;
1052 }
1053 break;
1054
1055 case Opt_fscontext:
1056 if (fscontext) {
1057 rc = -EINVAL;
1058 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1059 goto out_err;
1060 }
1061 fscontext = match_strdup(&args[0]);
1062 if (!fscontext) {
1063 rc = -ENOMEM;
1064 goto out_err;
1065 }
1066 break;
1067
1068 case Opt_rootcontext:
1069 if (rootcontext) {
1070 rc = -EINVAL;
1071 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1072 goto out_err;
1073 }
1074 rootcontext = match_strdup(&args[0]);
1075 if (!rootcontext) {
1076 rc = -ENOMEM;
1077 goto out_err;
1078 }
1079 break;
1080
1081 case Opt_defcontext:
1082 if (context || defcontext) {
1083 rc = -EINVAL;
1084 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1085 goto out_err;
1086 }
1087 defcontext = match_strdup(&args[0]);
1088 if (!defcontext) {
1089 rc = -ENOMEM;
1090 goto out_err;
1091 }
1092 break;
1093 case Opt_labelsupport:
1094 break;
1095 default:
1096 rc = -EINVAL;
1097 printk(KERN_WARNING "SELinux: unknown mount option\n");
1098 goto out_err;
1099
1100 }
1101 }
1102
1103 rc = -ENOMEM;
1104 opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1105 if (!opts->mnt_opts)
1106 goto out_err;
1107
1108 opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1109 GFP_KERNEL);
1110 if (!opts->mnt_opts_flags) {
1111 kfree(opts->mnt_opts);
1112 goto out_err;
1113 }
1114
1115 if (fscontext) {
1116 opts->mnt_opts[num_mnt_opts] = fscontext;
1117 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1118 }
1119 if (context) {
1120 opts->mnt_opts[num_mnt_opts] = context;
1121 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1122 }
1123 if (rootcontext) {
1124 opts->mnt_opts[num_mnt_opts] = rootcontext;
1125 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1126 }
1127 if (defcontext) {
1128 opts->mnt_opts[num_mnt_opts] = defcontext;
1129 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1130 }
1131
1132 opts->num_mnt_opts = num_mnt_opts;
1133 return 0;
1134
1135out_err:
1136 kfree(context);
1137 kfree(defcontext);
1138 kfree(fscontext);
1139 kfree(rootcontext);
1140 return rc;
1141}
1142/*
1143 * string mount options parsing and call set the sbsec
1144 */
1145static int superblock_doinit(struct super_block *sb, void *data)
1146{
1147 int rc = 0;
1148 char *options = data;
1149 struct security_mnt_opts opts;
1150
1151 security_init_mnt_opts(&opts);
1152
1153 if (!data)
1154 goto out;
1155
1156 BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1157
1158 rc = selinux_parse_opts_str(options, &opts);
1159 if (rc)
1160 goto out_err;
1161
1162out:
1163 rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1164
1165out_err:
1166 security_free_mnt_opts(&opts);
1167 return rc;
1168}
1169
1170static void selinux_write_opts(struct seq_file *m,
1171 struct security_mnt_opts *opts)
1172{
1173 int i;
1174 char *prefix;
1175
1176 for (i = 0; i < opts->num_mnt_opts; i++) {
1177 char *has_comma;
1178
1179 if (opts->mnt_opts[i])
1180 has_comma = strchr(opts->mnt_opts[i], ',');
1181 else
1182 has_comma = NULL;
1183
1184 switch (opts->mnt_opts_flags[i]) {
1185 case CONTEXT_MNT:
1186 prefix = CONTEXT_STR;
1187 break;
1188 case FSCONTEXT_MNT:
1189 prefix = FSCONTEXT_STR;
1190 break;
1191 case ROOTCONTEXT_MNT:
1192 prefix = ROOTCONTEXT_STR;
1193 break;
1194 case DEFCONTEXT_MNT:
1195 prefix = DEFCONTEXT_STR;
1196 break;
1197 case SBLABEL_MNT:
1198 seq_putc(m, ',');
1199 seq_puts(m, LABELSUPP_STR);
1200 continue;
1201 default:
1202 BUG();
1203 return;
1204 };
1205 /* we need a comma before each option */
1206 seq_putc(m, ',');
1207 seq_puts(m, prefix);
1208 if (has_comma)
1209 seq_putc(m, '\"');
1210 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1211 if (has_comma)
1212 seq_putc(m, '\"');
1213 }
1214}
1215
1216static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1217{
1218 struct security_mnt_opts opts;
1219 int rc;
1220
1221 rc = selinux_get_mnt_opts(sb, &opts);
1222 if (rc) {
1223 /* before policy load we may get EINVAL, don't show anything */
1224 if (rc == -EINVAL)
1225 rc = 0;
1226 return rc;
1227 }
1228
1229 selinux_write_opts(m, &opts);
1230
1231 security_free_mnt_opts(&opts);
1232
1233 return rc;
1234}
1235
1236static inline u16 inode_mode_to_security_class(umode_t mode)
1237{
1238 switch (mode & S_IFMT) {
1239 case S_IFSOCK:
1240 return SECCLASS_SOCK_FILE;
1241 case S_IFLNK:
1242 return SECCLASS_LNK_FILE;
1243 case S_IFREG:
1244 return SECCLASS_FILE;
1245 case S_IFBLK:
1246 return SECCLASS_BLK_FILE;
1247 case S_IFDIR:
1248 return SECCLASS_DIR;
1249 case S_IFCHR:
1250 return SECCLASS_CHR_FILE;
1251 case S_IFIFO:
1252 return SECCLASS_FIFO_FILE;
1253
1254 }
1255
1256 return SECCLASS_FILE;
1257}
1258
1259static inline int default_protocol_stream(int protocol)
1260{
1261 return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1262}
1263
1264static inline int default_protocol_dgram(int protocol)
1265{
1266 return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1267}
1268
1269static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1270{
1271 switch (family) {
1272 case PF_UNIX:
1273 switch (type) {
1274 case SOCK_STREAM:
1275 case SOCK_SEQPACKET:
1276 return SECCLASS_UNIX_STREAM_SOCKET;
1277 case SOCK_DGRAM:
1278 return SECCLASS_UNIX_DGRAM_SOCKET;
1279 }
1280 break;
1281 case PF_INET:
1282 case PF_INET6:
1283 switch (type) {
1284 case SOCK_STREAM:
1285 if (default_protocol_stream(protocol))
1286 return SECCLASS_TCP_SOCKET;
1287 else
1288 return SECCLASS_RAWIP_SOCKET;
1289 case SOCK_DGRAM:
1290 if (default_protocol_dgram(protocol))
1291 return SECCLASS_UDP_SOCKET;
1292 else
1293 return SECCLASS_RAWIP_SOCKET;
1294 case SOCK_DCCP:
1295 return SECCLASS_DCCP_SOCKET;
1296 default:
1297 return SECCLASS_RAWIP_SOCKET;
1298 }
1299 break;
1300 case PF_NETLINK:
1301 switch (protocol) {
1302 case NETLINK_ROUTE:
1303 return SECCLASS_NETLINK_ROUTE_SOCKET;
1304 case NETLINK_SOCK_DIAG:
1305 return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1306 case NETLINK_NFLOG:
1307 return SECCLASS_NETLINK_NFLOG_SOCKET;
1308 case NETLINK_XFRM:
1309 return SECCLASS_NETLINK_XFRM_SOCKET;
1310 case NETLINK_SELINUX:
1311 return SECCLASS_NETLINK_SELINUX_SOCKET;
1312 case NETLINK_ISCSI:
1313 return SECCLASS_NETLINK_ISCSI_SOCKET;
1314 case NETLINK_AUDIT:
1315 return SECCLASS_NETLINK_AUDIT_SOCKET;
1316 case NETLINK_FIB_LOOKUP:
1317 return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1318 case NETLINK_CONNECTOR:
1319 return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1320 case NETLINK_NETFILTER:
1321 return SECCLASS_NETLINK_NETFILTER_SOCKET;
1322 case NETLINK_DNRTMSG:
1323 return SECCLASS_NETLINK_DNRT_SOCKET;
1324 case NETLINK_KOBJECT_UEVENT:
1325 return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1326 case NETLINK_GENERIC:
1327 return SECCLASS_NETLINK_GENERIC_SOCKET;
1328 case NETLINK_SCSITRANSPORT:
1329 return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1330 case NETLINK_RDMA:
1331 return SECCLASS_NETLINK_RDMA_SOCKET;
1332 case NETLINK_CRYPTO:
1333 return SECCLASS_NETLINK_CRYPTO_SOCKET;
1334 default:
1335 return SECCLASS_NETLINK_SOCKET;
1336 }
1337 case PF_PACKET:
1338 return SECCLASS_PACKET_SOCKET;
1339 case PF_KEY:
1340 return SECCLASS_KEY_SOCKET;
1341 case PF_APPLETALK:
1342 return SECCLASS_APPLETALK_SOCKET;
1343 }
1344
1345 return SECCLASS_SOCKET;
1346}
1347
1348static int selinux_genfs_get_sid(struct dentry *dentry,
1349 u16 tclass,
1350 u16 flags,
1351 u32 *sid)
1352{
1353 int rc;
1354 struct super_block *sb = dentry->d_sb;
1355 char *buffer, *path;
1356
1357 buffer = (char *)__get_free_page(GFP_KERNEL);
1358 if (!buffer)
1359 return -ENOMEM;
1360
1361 path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1362 if (IS_ERR(path))
1363 rc = PTR_ERR(path);
1364 else {
1365 if (flags & SE_SBPROC) {
1366 /* each process gets a /proc/PID/ entry. Strip off the
1367 * PID part to get a valid selinux labeling.
1368 * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1369 while (path[1] >= '0' && path[1] <= '9') {
1370 path[1] = '/';
1371 path++;
1372 }
1373 }
1374 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
1375 }
1376 free_page((unsigned long)buffer);
1377 return rc;
1378}
1379
1380/* The inode's security attributes must be initialized before first use. */
1381static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1382{
1383 struct superblock_security_struct *sbsec = NULL;
1384 struct inode_security_struct *isec = inode->i_security;
1385 u32 task_sid, sid = 0;
1386 u16 sclass;
1387 struct dentry *dentry;
1388#define INITCONTEXTLEN 255
1389 char *context = NULL;
1390 unsigned len = 0;
1391 int rc = 0;
1392
1393 if (isec->initialized == LABEL_INITIALIZED)
1394 return 0;
1395
1396 spin_lock(&isec->lock);
1397 if (isec->initialized == LABEL_INITIALIZED)
1398 goto out_unlock;
1399
1400 if (isec->sclass == SECCLASS_FILE)
1401 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1402
1403 sbsec = inode->i_sb->s_security;
1404 if (!(sbsec->flags & SE_SBINITIALIZED)) {
1405 /* Defer initialization until selinux_complete_init,
1406 after the initial policy is loaded and the security
1407 server is ready to handle calls. */
1408 spin_lock(&sbsec->isec_lock);
1409 if (list_empty(&isec->list))
1410 list_add(&isec->list, &sbsec->isec_head);
1411 spin_unlock(&sbsec->isec_lock);
1412 goto out_unlock;
1413 }
1414
1415 sclass = isec->sclass;
1416 task_sid = isec->task_sid;
1417 sid = isec->sid;
1418 isec->initialized = LABEL_PENDING;
1419 spin_unlock(&isec->lock);
1420
1421 switch (sbsec->behavior) {
1422 case SECURITY_FS_USE_NATIVE:
1423 break;
1424 case SECURITY_FS_USE_XATTR:
1425 if (!(inode->i_opflags & IOP_XATTR)) {
1426 sid = sbsec->def_sid;
1427 break;
1428 }
1429 /* Need a dentry, since the xattr API requires one.
1430 Life would be simpler if we could just pass the inode. */
1431 if (opt_dentry) {
1432 /* Called from d_instantiate or d_splice_alias. */
1433 dentry = dget(opt_dentry);
1434 } else {
1435 /* Called from selinux_complete_init, try to find a dentry. */
1436 dentry = d_find_alias(inode);
1437 }
1438 if (!dentry) {
1439 /*
1440 * this is can be hit on boot when a file is accessed
1441 * before the policy is loaded. When we load policy we
1442 * may find inodes that have no dentry on the
1443 * sbsec->isec_head list. No reason to complain as these
1444 * will get fixed up the next time we go through
1445 * inode_doinit with a dentry, before these inodes could
1446 * be used again by userspace.
1447 */
1448 goto out;
1449 }
1450
1451 len = INITCONTEXTLEN;
1452 context = kmalloc(len+1, GFP_NOFS);
1453 if (!context) {
1454 rc = -ENOMEM;
1455 dput(dentry);
1456 goto out;
1457 }
1458 context[len] = '\0';
1459 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1460 if (rc == -ERANGE) {
1461 kfree(context);
1462
1463 /* Need a larger buffer. Query for the right size. */
1464 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1465 if (rc < 0) {
1466 dput(dentry);
1467 goto out;
1468 }
1469 len = rc;
1470 context = kmalloc(len+1, GFP_NOFS);
1471 if (!context) {
1472 rc = -ENOMEM;
1473 dput(dentry);
1474 goto out;
1475 }
1476 context[len] = '\0';
1477 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1478 }
1479 dput(dentry);
1480 if (rc < 0) {
1481 if (rc != -ENODATA) {
1482 printk(KERN_WARNING "SELinux: %s: getxattr returned "
1483 "%d for dev=%s ino=%ld\n", __func__,
1484 -rc, inode->i_sb->s_id, inode->i_ino);
1485 kfree(context);
1486 goto out;
1487 }
1488 /* Map ENODATA to the default file SID */
1489 sid = sbsec->def_sid;
1490 rc = 0;
1491 } else {
1492 rc = security_context_to_sid_default(context, rc, &sid,
1493 sbsec->def_sid,
1494 GFP_NOFS);
1495 if (rc) {
1496 char *dev = inode->i_sb->s_id;
1497 unsigned long ino = inode->i_ino;
1498
1499 if (rc == -EINVAL) {
1500 if (printk_ratelimit())
1501 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1502 "context=%s. This indicates you may need to relabel the inode or the "
1503 "filesystem in question.\n", ino, dev, context);
1504 } else {
1505 printk(KERN_WARNING "SELinux: %s: context_to_sid(%s) "
1506 "returned %d for dev=%s ino=%ld\n",
1507 __func__, context, -rc, dev, ino);
1508 }
1509 kfree(context);
1510 /* Leave with the unlabeled SID */
1511 rc = 0;
1512 break;
1513 }
1514 }
1515 kfree(context);
1516 break;
1517 case SECURITY_FS_USE_TASK:
1518 sid = task_sid;
1519 break;
1520 case SECURITY_FS_USE_TRANS:
1521 /* Default to the fs SID. */
1522 sid = sbsec->sid;
1523
1524 /* Try to obtain a transition SID. */
1525 rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
1526 if (rc)
1527 goto out;
1528 break;
1529 case SECURITY_FS_USE_MNTPOINT:
1530 sid = sbsec->mntpoint_sid;
1531 break;
1532 default:
1533 /* Default to the fs superblock SID. */
1534 sid = sbsec->sid;
1535
1536 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1537 /* We must have a dentry to determine the label on
1538 * procfs inodes */
1539 if (opt_dentry)
1540 /* Called from d_instantiate or
1541 * d_splice_alias. */
1542 dentry = dget(opt_dentry);
1543 else
1544 /* Called from selinux_complete_init, try to
1545 * find a dentry. */
1546 dentry = d_find_alias(inode);
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 dput(dentry);
1561 if (rc)
1562 goto out;
1563 }
1564 break;
1565 }
1566
1567out:
1568 spin_lock(&isec->lock);
1569 if (isec->initialized == LABEL_PENDING) {
1570 if (!sid || rc) {
1571 isec->initialized = LABEL_INVALID;
1572 goto out_unlock;
1573 }
1574
1575 isec->initialized = LABEL_INITIALIZED;
1576 isec->sid = sid;
1577 }
1578
1579out_unlock:
1580 spin_unlock(&isec->lock);
1581 return rc;
1582}
1583
1584/* Convert a Linux signal to an access vector. */
1585static inline u32 signal_to_av(int sig)
1586{
1587 u32 perm = 0;
1588
1589 switch (sig) {
1590 case SIGCHLD:
1591 /* Commonly granted from child to parent. */
1592 perm = PROCESS__SIGCHLD;
1593 break;
1594 case SIGKILL:
1595 /* Cannot be caught or ignored */
1596 perm = PROCESS__SIGKILL;
1597 break;
1598 case SIGSTOP:
1599 /* Cannot be caught or ignored */
1600 perm = PROCESS__SIGSTOP;
1601 break;
1602 default:
1603 /* All other signals. */
1604 perm = PROCESS__SIGNAL;
1605 break;
1606 }
1607
1608 return perm;
1609}
1610
1611/*
1612 * Check permission between a pair of credentials
1613 * fork check, ptrace check, etc.
1614 */
1615static int cred_has_perm(const struct cred *actor,
1616 const struct cred *target,
1617 u32 perms)
1618{
1619 u32 asid = cred_sid(actor), tsid = cred_sid(target);
1620
1621 return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1622}
1623
1624/*
1625 * Check permission between a pair of tasks, e.g. signal checks,
1626 * fork check, ptrace check, etc.
1627 * tsk1 is the actor and tsk2 is the target
1628 * - this uses the default subjective creds of tsk1
1629 */
1630static int task_has_perm(const struct task_struct *tsk1,
1631 const struct task_struct *tsk2,
1632 u32 perms)
1633{
1634 const struct task_security_struct *__tsec1, *__tsec2;
1635 u32 sid1, sid2;
1636
1637 rcu_read_lock();
1638 __tsec1 = __task_cred(tsk1)->security; sid1 = __tsec1->sid;
1639 __tsec2 = __task_cred(tsk2)->security; sid2 = __tsec2->sid;
1640 rcu_read_unlock();
1641 return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1642}
1643
1644/*
1645 * Check permission between current and another task, e.g. signal checks,
1646 * fork check, ptrace check, etc.
1647 * current is the actor and tsk2 is the target
1648 * - this uses current's subjective creds
1649 */
1650static int current_has_perm(const struct task_struct *tsk,
1651 u32 perms)
1652{
1653 u32 sid, tsid;
1654
1655 sid = current_sid();
1656 tsid = task_sid(tsk);
1657 return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1658}
1659
1660#if CAP_LAST_CAP > 63
1661#error Fix SELinux to handle capabilities > 63.
1662#endif
1663
1664/* Check whether a task is allowed to use a capability. */
1665static int cred_has_capability(const struct cred *cred,
1666 int cap, int audit, bool initns)
1667{
1668 struct common_audit_data ad;
1669 struct av_decision avd;
1670 u16 sclass;
1671 u32 sid = cred_sid(cred);
1672 u32 av = CAP_TO_MASK(cap);
1673 int rc;
1674
1675 ad.type = LSM_AUDIT_DATA_CAP;
1676 ad.u.cap = cap;
1677
1678 switch (CAP_TO_INDEX(cap)) {
1679 case 0:
1680 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1681 break;
1682 case 1:
1683 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1684 break;
1685 default:
1686 printk(KERN_ERR
1687 "SELinux: out of range capability %d\n", cap);
1688 BUG();
1689 return -EINVAL;
1690 }
1691
1692 rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1693 if (audit == SECURITY_CAP_AUDIT) {
1694 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1695 if (rc2)
1696 return rc2;
1697 }
1698 return rc;
1699}
1700
1701/* Check whether a task is allowed to use a system operation. */
1702static int task_has_system(struct task_struct *tsk,
1703 u32 perms)
1704{
1705 u32 sid = task_sid(tsk);
1706
1707 return avc_has_perm(sid, SECINITSID_KERNEL,
1708 SECCLASS_SYSTEM, perms, NULL);
1709}
1710
1711/* Check whether a task has a particular permission to an inode.
1712 The 'adp' parameter is optional and allows other audit
1713 data to be passed (e.g. the dentry). */
1714static int inode_has_perm(const struct cred *cred,
1715 struct inode *inode,
1716 u32 perms,
1717 struct common_audit_data *adp)
1718{
1719 struct inode_security_struct *isec;
1720 u32 sid;
1721
1722 validate_creds(cred);
1723
1724 if (unlikely(IS_PRIVATE(inode)))
1725 return 0;
1726
1727 sid = cred_sid(cred);
1728 isec = inode->i_security;
1729
1730 return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1731}
1732
1733/* Same as inode_has_perm, but pass explicit audit data containing
1734 the dentry to help the auditing code to more easily generate the
1735 pathname if needed. */
1736static inline int dentry_has_perm(const struct cred *cred,
1737 struct dentry *dentry,
1738 u32 av)
1739{
1740 struct inode *inode = d_backing_inode(dentry);
1741 struct common_audit_data ad;
1742
1743 ad.type = LSM_AUDIT_DATA_DENTRY;
1744 ad.u.dentry = dentry;
1745 __inode_security_revalidate(inode, dentry, true);
1746 return inode_has_perm(cred, inode, av, &ad);
1747}
1748
1749/* Same as inode_has_perm, but pass explicit audit data containing
1750 the path to help the auditing code to more easily generate the
1751 pathname if needed. */
1752static inline int path_has_perm(const struct cred *cred,
1753 const struct path *path,
1754 u32 av)
1755{
1756 struct inode *inode = d_backing_inode(path->dentry);
1757 struct common_audit_data ad;
1758
1759 ad.type = LSM_AUDIT_DATA_PATH;
1760 ad.u.path = *path;
1761 __inode_security_revalidate(inode, path->dentry, true);
1762 return inode_has_perm(cred, inode, av, &ad);
1763}
1764
1765/* Same as path_has_perm, but uses the inode from the file struct. */
1766static inline int file_path_has_perm(const struct cred *cred,
1767 struct file *file,
1768 u32 av)
1769{
1770 struct common_audit_data ad;
1771
1772 ad.type = LSM_AUDIT_DATA_FILE;
1773 ad.u.file = file;
1774 return inode_has_perm(cred, file_inode(file), av, &ad);
1775}
1776
1777/* Check whether a task can use an open file descriptor to
1778 access an inode in a given way. Check access to the
1779 descriptor itself, and then use dentry_has_perm to
1780 check a particular permission to the file.
1781 Access to the descriptor is implicitly granted if it
1782 has the same SID as the process. If av is zero, then
1783 access to the file is not checked, e.g. for cases
1784 where only the descriptor is affected like seek. */
1785static int file_has_perm(const struct cred *cred,
1786 struct file *file,
1787 u32 av)
1788{
1789 struct file_security_struct *fsec = file->f_security;
1790 struct inode *inode = file_inode(file);
1791 struct common_audit_data ad;
1792 u32 sid = cred_sid(cred);
1793 int rc;
1794
1795 ad.type = LSM_AUDIT_DATA_FILE;
1796 ad.u.file = file;
1797
1798 if (sid != fsec->sid) {
1799 rc = avc_has_perm(sid, fsec->sid,
1800 SECCLASS_FD,
1801 FD__USE,
1802 &ad);
1803 if (rc)
1804 goto out;
1805 }
1806
1807 /* av is zero if only checking access to the descriptor. */
1808 rc = 0;
1809 if (av)
1810 rc = inode_has_perm(cred, inode, av, &ad);
1811
1812out:
1813 return rc;
1814}
1815
1816/*
1817 * Determine the label for an inode that might be unioned.
1818 */
1819static int
1820selinux_determine_inode_label(const struct task_security_struct *tsec,
1821 struct inode *dir,
1822 const struct qstr *name, u16 tclass,
1823 u32 *_new_isid)
1824{
1825 const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1826
1827 if ((sbsec->flags & SE_SBINITIALIZED) &&
1828 (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1829 *_new_isid = sbsec->mntpoint_sid;
1830 } else if ((sbsec->flags & SBLABEL_MNT) &&
1831 tsec->create_sid) {
1832 *_new_isid = tsec->create_sid;
1833 } else {
1834 const struct inode_security_struct *dsec = inode_security(dir);
1835 return security_transition_sid(tsec->sid, dsec->sid, tclass,
1836 name, _new_isid);
1837 }
1838
1839 return 0;
1840}
1841
1842/* Check whether a task can create a file. */
1843static int may_create(struct inode *dir,
1844 struct dentry *dentry,
1845 u16 tclass)
1846{
1847 const struct task_security_struct *tsec = current_security();
1848 struct inode_security_struct *dsec;
1849 struct superblock_security_struct *sbsec;
1850 u32 sid, newsid;
1851 struct common_audit_data ad;
1852 int rc;
1853
1854 dsec = inode_security(dir);
1855 sbsec = dir->i_sb->s_security;
1856
1857 sid = tsec->sid;
1858
1859 ad.type = LSM_AUDIT_DATA_DENTRY;
1860 ad.u.dentry = dentry;
1861
1862 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1863 DIR__ADD_NAME | DIR__SEARCH,
1864 &ad);
1865 if (rc)
1866 return rc;
1867
1868 rc = selinux_determine_inode_label(current_security(), dir,
1869 &dentry->d_name, tclass, &newsid);
1870 if (rc)
1871 return rc;
1872
1873 rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1874 if (rc)
1875 return rc;
1876
1877 return avc_has_perm(newsid, sbsec->sid,
1878 SECCLASS_FILESYSTEM,
1879 FILESYSTEM__ASSOCIATE, &ad);
1880}
1881
1882/* Check whether a task can create a key. */
1883static int may_create_key(u32 ksid,
1884 struct task_struct *ctx)
1885{
1886 u32 sid = task_sid(ctx);
1887
1888 return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1889}
1890
1891#define MAY_LINK 0
1892#define MAY_UNLINK 1
1893#define MAY_RMDIR 2
1894
1895/* Check whether a task can link, unlink, or rmdir a file/directory. */
1896static int may_link(struct inode *dir,
1897 struct dentry *dentry,
1898 int kind)
1899
1900{
1901 struct inode_security_struct *dsec, *isec;
1902 struct common_audit_data ad;
1903 u32 sid = current_sid();
1904 u32 av;
1905 int rc;
1906
1907 dsec = inode_security(dir);
1908 isec = backing_inode_security(dentry);
1909
1910 ad.type = LSM_AUDIT_DATA_DENTRY;
1911 ad.u.dentry = dentry;
1912
1913 av = DIR__SEARCH;
1914 av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1915 rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1916 if (rc)
1917 return rc;
1918
1919 switch (kind) {
1920 case MAY_LINK:
1921 av = FILE__LINK;
1922 break;
1923 case MAY_UNLINK:
1924 av = FILE__UNLINK;
1925 break;
1926 case MAY_RMDIR:
1927 av = DIR__RMDIR;
1928 break;
1929 default:
1930 printk(KERN_WARNING "SELinux: %s: unrecognized kind %d\n",
1931 __func__, kind);
1932 return 0;
1933 }
1934
1935 rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1936 return rc;
1937}
1938
1939static inline int may_rename(struct inode *old_dir,
1940 struct dentry *old_dentry,
1941 struct inode *new_dir,
1942 struct dentry *new_dentry)
1943{
1944 struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1945 struct common_audit_data ad;
1946 u32 sid = current_sid();
1947 u32 av;
1948 int old_is_dir, new_is_dir;
1949 int rc;
1950
1951 old_dsec = inode_security(old_dir);
1952 old_isec = backing_inode_security(old_dentry);
1953 old_is_dir = d_is_dir(old_dentry);
1954 new_dsec = inode_security(new_dir);
1955
1956 ad.type = LSM_AUDIT_DATA_DENTRY;
1957
1958 ad.u.dentry = old_dentry;
1959 rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1960 DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1961 if (rc)
1962 return rc;
1963 rc = avc_has_perm(sid, old_isec->sid,
1964 old_isec->sclass, FILE__RENAME, &ad);
1965 if (rc)
1966 return rc;
1967 if (old_is_dir && new_dir != old_dir) {
1968 rc = avc_has_perm(sid, old_isec->sid,
1969 old_isec->sclass, DIR__REPARENT, &ad);
1970 if (rc)
1971 return rc;
1972 }
1973
1974 ad.u.dentry = new_dentry;
1975 av = DIR__ADD_NAME | DIR__SEARCH;
1976 if (d_is_positive(new_dentry))
1977 av |= DIR__REMOVE_NAME;
1978 rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1979 if (rc)
1980 return rc;
1981 if (d_is_positive(new_dentry)) {
1982 new_isec = backing_inode_security(new_dentry);
1983 new_is_dir = d_is_dir(new_dentry);
1984 rc = avc_has_perm(sid, new_isec->sid,
1985 new_isec->sclass,
1986 (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1987 if (rc)
1988 return rc;
1989 }
1990
1991 return 0;
1992}
1993
1994/* Check whether a task can perform a filesystem operation. */
1995static int superblock_has_perm(const struct cred *cred,
1996 struct super_block *sb,
1997 u32 perms,
1998 struct common_audit_data *ad)
1999{
2000 struct superblock_security_struct *sbsec;
2001 u32 sid = cred_sid(cred);
2002
2003 sbsec = sb->s_security;
2004 return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2005}
2006
2007/* Convert a Linux mode and permission mask to an access vector. */
2008static inline u32 file_mask_to_av(int mode, int mask)
2009{
2010 u32 av = 0;
2011
2012 if (!S_ISDIR(mode)) {
2013 if (mask & MAY_EXEC)
2014 av |= FILE__EXECUTE;
2015 if (mask & MAY_READ)
2016 av |= FILE__READ;
2017
2018 if (mask & MAY_APPEND)
2019 av |= FILE__APPEND;
2020 else if (mask & MAY_WRITE)
2021 av |= FILE__WRITE;
2022
2023 } else {
2024 if (mask & MAY_EXEC)
2025 av |= DIR__SEARCH;
2026 if (mask & MAY_WRITE)
2027 av |= DIR__WRITE;
2028 if (mask & MAY_READ)
2029 av |= DIR__READ;
2030 }
2031
2032 return av;
2033}
2034
2035/* Convert a Linux file to an access vector. */
2036static inline u32 file_to_av(struct file *file)
2037{
2038 u32 av = 0;
2039
2040 if (file->f_mode & FMODE_READ)
2041 av |= FILE__READ;
2042 if (file->f_mode & FMODE_WRITE) {
2043 if (file->f_flags & O_APPEND)
2044 av |= FILE__APPEND;
2045 else
2046 av |= FILE__WRITE;
2047 }
2048 if (!av) {
2049 /*
2050 * Special file opened with flags 3 for ioctl-only use.
2051 */
2052 av = FILE__IOCTL;
2053 }
2054
2055 return av;
2056}
2057
2058/*
2059 * Convert a file to an access vector and include the correct open
2060 * open permission.
2061 */
2062static inline u32 open_file_to_av(struct file *file)
2063{
2064 u32 av = file_to_av(file);
2065
2066 if (selinux_policycap_openperm)
2067 av |= FILE__OPEN;
2068
2069 return av;
2070}
2071
2072/* Hook functions begin here. */
2073
2074static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2075{
2076 u32 mysid = current_sid();
2077 u32 mgrsid = task_sid(mgr);
2078
2079 return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
2080 BINDER__SET_CONTEXT_MGR, NULL);
2081}
2082
2083static int selinux_binder_transaction(struct task_struct *from,
2084 struct task_struct *to)
2085{
2086 u32 mysid = current_sid();
2087 u32 fromsid = task_sid(from);
2088 u32 tosid = task_sid(to);
2089 int rc;
2090
2091 if (mysid != fromsid) {
2092 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2093 BINDER__IMPERSONATE, NULL);
2094 if (rc)
2095 return rc;
2096 }
2097
2098 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2099 NULL);
2100}
2101
2102static int selinux_binder_transfer_binder(struct task_struct *from,
2103 struct task_struct *to)
2104{
2105 u32 fromsid = task_sid(from);
2106 u32 tosid = task_sid(to);
2107
2108 return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2109 NULL);
2110}
2111
2112static int selinux_binder_transfer_file(struct task_struct *from,
2113 struct task_struct *to,
2114 struct file *file)
2115{
2116 u32 sid = task_sid(to);
2117 struct file_security_struct *fsec = file->f_security;
2118 struct dentry *dentry = file->f_path.dentry;
2119 struct inode_security_struct *isec;
2120 struct common_audit_data ad;
2121 int rc;
2122
2123 ad.type = LSM_AUDIT_DATA_PATH;
2124 ad.u.path = file->f_path;
2125
2126 if (sid != fsec->sid) {
2127 rc = avc_has_perm(sid, fsec->sid,
2128 SECCLASS_FD,
2129 FD__USE,
2130 &ad);
2131 if (rc)
2132 return rc;
2133 }
2134
2135 if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2136 return 0;
2137
2138 isec = backing_inode_security(dentry);
2139 return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2140 &ad);
2141}
2142
2143static int selinux_ptrace_access_check(struct task_struct *child,
2144 unsigned int mode)
2145{
2146 if (mode & PTRACE_MODE_READ) {
2147 u32 sid = current_sid();
2148 u32 csid = task_sid(child);
2149 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2150 }
2151
2152 return current_has_perm(child, PROCESS__PTRACE);
2153}
2154
2155static int selinux_ptrace_traceme(struct task_struct *parent)
2156{
2157 return task_has_perm(parent, current, PROCESS__PTRACE);
2158}
2159
2160static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2161 kernel_cap_t *inheritable, kernel_cap_t *permitted)
2162{
2163 return current_has_perm(target, PROCESS__GETCAP);
2164}
2165
2166static int selinux_capset(struct cred *new, const struct cred *old,
2167 const kernel_cap_t *effective,
2168 const kernel_cap_t *inheritable,
2169 const kernel_cap_t *permitted)
2170{
2171 return cred_has_perm(old, new, PROCESS__SETCAP);
2172}
2173
2174/*
2175 * (This comment used to live with the selinux_task_setuid hook,
2176 * which was removed).
2177 *
2178 * Since setuid only affects the current process, and since the SELinux
2179 * controls are not based on the Linux identity attributes, SELinux does not
2180 * need to control this operation. However, SELinux does control the use of
2181 * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2182 */
2183
2184static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2185 int cap, int audit)
2186{
2187 return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2188}
2189
2190static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2191{
2192 const struct cred *cred = current_cred();
2193 int rc = 0;
2194
2195 if (!sb)
2196 return 0;
2197
2198 switch (cmds) {
2199 case Q_SYNC:
2200 case Q_QUOTAON:
2201 case Q_QUOTAOFF:
2202 case Q_SETINFO:
2203 case Q_SETQUOTA:
2204 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2205 break;
2206 case Q_GETFMT:
2207 case Q_GETINFO:
2208 case Q_GETQUOTA:
2209 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2210 break;
2211 default:
2212 rc = 0; /* let the kernel handle invalid cmds */
2213 break;
2214 }
2215 return rc;
2216}
2217
2218static int selinux_quota_on(struct dentry *dentry)
2219{
2220 const struct cred *cred = current_cred();
2221
2222 return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2223}
2224
2225static int selinux_syslog(int type)
2226{
2227 int rc;
2228
2229 switch (type) {
2230 case SYSLOG_ACTION_READ_ALL: /* Read last kernel messages */
2231 case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2232 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2233 break;
2234 case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2235 case SYSLOG_ACTION_CONSOLE_ON: /* Enable logging to console */
2236 /* Set level of messages printed to console */
2237 case SYSLOG_ACTION_CONSOLE_LEVEL:
2238 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2239 break;
2240 case SYSLOG_ACTION_CLOSE: /* Close log */
2241 case SYSLOG_ACTION_OPEN: /* Open log */
2242 case SYSLOG_ACTION_READ: /* Read from log */
2243 case SYSLOG_ACTION_READ_CLEAR: /* Read/clear last kernel messages */
2244 case SYSLOG_ACTION_CLEAR: /* Clear ring buffer */
2245 default:
2246 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2247 break;
2248 }
2249 return rc;
2250}
2251
2252/*
2253 * Check that a process has enough memory to allocate a new virtual
2254 * mapping. 0 means there is enough memory for the allocation to
2255 * succeed and -ENOMEM implies there is not.
2256 *
2257 * Do not audit the selinux permission check, as this is applied to all
2258 * processes that allocate mappings.
2259 */
2260static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2261{
2262 int rc, cap_sys_admin = 0;
2263
2264 rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2265 SECURITY_CAP_NOAUDIT, true);
2266 if (rc == 0)
2267 cap_sys_admin = 1;
2268
2269 return cap_sys_admin;
2270}
2271
2272/* binprm security operations */
2273
2274static u32 ptrace_parent_sid(struct task_struct *task)
2275{
2276 u32 sid = 0;
2277 struct task_struct *tracer;
2278
2279 rcu_read_lock();
2280 tracer = ptrace_parent(task);
2281 if (tracer)
2282 sid = task_sid(tracer);
2283 rcu_read_unlock();
2284
2285 return sid;
2286}
2287
2288static int check_nnp_nosuid(const struct linux_binprm *bprm,
2289 const struct task_security_struct *old_tsec,
2290 const struct task_security_struct *new_tsec)
2291{
2292 int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2293 int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2294 int rc;
2295
2296 if (!nnp && !nosuid)
2297 return 0; /* neither NNP nor nosuid */
2298
2299 if (new_tsec->sid == old_tsec->sid)
2300 return 0; /* No change in credentials */
2301
2302 /*
2303 * The only transitions we permit under NNP or nosuid
2304 * are transitions to bounded SIDs, i.e. SIDs that are
2305 * guaranteed to only be allowed a subset of the permissions
2306 * of the current SID.
2307 */
2308 rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2309 if (rc) {
2310 /*
2311 * On failure, preserve the errno values for NNP vs nosuid.
2312 * NNP: Operation not permitted for caller.
2313 * nosuid: Permission denied to file.
2314 */
2315 if (nnp)
2316 return -EPERM;
2317 else
2318 return -EACCES;
2319 }
2320 return 0;
2321}
2322
2323static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2324{
2325 const struct task_security_struct *old_tsec;
2326 struct task_security_struct *new_tsec;
2327 struct inode_security_struct *isec;
2328 struct common_audit_data ad;
2329 struct inode *inode = file_inode(bprm->file);
2330 int rc;
2331
2332 /* SELinux context only depends on initial program or script and not
2333 * the script interpreter */
2334 if (bprm->cred_prepared)
2335 return 0;
2336
2337 old_tsec = current_security();
2338 new_tsec = bprm->cred->security;
2339 isec = inode_security(inode);
2340
2341 /* Default to the current task SID. */
2342 new_tsec->sid = old_tsec->sid;
2343 new_tsec->osid = old_tsec->sid;
2344
2345 /* Reset fs, key, and sock SIDs on execve. */
2346 new_tsec->create_sid = 0;
2347 new_tsec->keycreate_sid = 0;
2348 new_tsec->sockcreate_sid = 0;
2349
2350 if (old_tsec->exec_sid) {
2351 new_tsec->sid = old_tsec->exec_sid;
2352 /* Reset exec SID on execve. */
2353 new_tsec->exec_sid = 0;
2354
2355 /* Fail on NNP or nosuid if not an allowed transition. */
2356 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2357 if (rc)
2358 return rc;
2359 } else {
2360 /* Check for a default transition on this program. */
2361 rc = security_transition_sid(old_tsec->sid, isec->sid,
2362 SECCLASS_PROCESS, NULL,
2363 &new_tsec->sid);
2364 if (rc)
2365 return rc;
2366
2367 /*
2368 * Fallback to old SID on NNP or nosuid if not an allowed
2369 * transition.
2370 */
2371 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2372 if (rc)
2373 new_tsec->sid = old_tsec->sid;
2374 }
2375
2376 ad.type = LSM_AUDIT_DATA_FILE;
2377 ad.u.file = bprm->file;
2378
2379 if (new_tsec->sid == old_tsec->sid) {
2380 rc = avc_has_perm(old_tsec->sid, isec->sid,
2381 SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2382 if (rc)
2383 return rc;
2384 } else {
2385 /* Check permissions for the transition. */
2386 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2387 SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2388 if (rc)
2389 return rc;
2390
2391 rc = avc_has_perm(new_tsec->sid, isec->sid,
2392 SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2393 if (rc)
2394 return rc;
2395
2396 /* Check for shared state */
2397 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2398 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2399 SECCLASS_PROCESS, PROCESS__SHARE,
2400 NULL);
2401 if (rc)
2402 return -EPERM;
2403 }
2404
2405 /* Make sure that anyone attempting to ptrace over a task that
2406 * changes its SID has the appropriate permit */
2407 if (bprm->unsafe &
2408 (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2409 u32 ptsid = ptrace_parent_sid(current);
2410 if (ptsid != 0) {
2411 rc = avc_has_perm(ptsid, new_tsec->sid,
2412 SECCLASS_PROCESS,
2413 PROCESS__PTRACE, NULL);
2414 if (rc)
2415 return -EPERM;
2416 }
2417 }
2418
2419 /* Clear any possibly unsafe personality bits on exec: */
2420 bprm->per_clear |= PER_CLEAR_ON_SETID;
2421 }
2422
2423 return 0;
2424}
2425
2426static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2427{
2428 const struct task_security_struct *tsec = current_security();
2429 u32 sid, osid;
2430 int atsecure = 0;
2431
2432 sid = tsec->sid;
2433 osid = tsec->osid;
2434
2435 if (osid != sid) {
2436 /* Enable secure mode for SIDs transitions unless
2437 the noatsecure permission is granted between
2438 the two SIDs, i.e. ahp returns 0. */
2439 atsecure = avc_has_perm(osid, sid,
2440 SECCLASS_PROCESS,
2441 PROCESS__NOATSECURE, NULL);
2442 }
2443
2444 return !!atsecure;
2445}
2446
2447static int match_file(const void *p, struct file *file, unsigned fd)
2448{
2449 return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2450}
2451
2452/* Derived from fs/exec.c:flush_old_files. */
2453static inline void flush_unauthorized_files(const struct cred *cred,
2454 struct files_struct *files)
2455{
2456 struct file *file, *devnull = NULL;
2457 struct tty_struct *tty;
2458 int drop_tty = 0;
2459 unsigned n;
2460
2461 tty = get_current_tty();
2462 if (tty) {
2463 spin_lock(&tty->files_lock);
2464 if (!list_empty(&tty->tty_files)) {
2465 struct tty_file_private *file_priv;
2466
2467 /* Revalidate access to controlling tty.
2468 Use file_path_has_perm on the tty path directly
2469 rather than using file_has_perm, as this particular
2470 open file may belong to another process and we are
2471 only interested in the inode-based check here. */
2472 file_priv = list_first_entry(&tty->tty_files,
2473 struct tty_file_private, list);
2474 file = file_priv->file;
2475 if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2476 drop_tty = 1;
2477 }
2478 spin_unlock(&tty->files_lock);
2479 tty_kref_put(tty);
2480 }
2481 /* Reset controlling tty. */
2482 if (drop_tty)
2483 no_tty();
2484
2485 /* Revalidate access to inherited open files. */
2486 n = iterate_fd(files, 0, match_file, cred);
2487 if (!n) /* none found? */
2488 return;
2489
2490 devnull = dentry_open(&selinux_null, O_RDWR, cred);
2491 if (IS_ERR(devnull))
2492 devnull = NULL;
2493 /* replace all the matching ones with this */
2494 do {
2495 replace_fd(n - 1, devnull, 0);
2496 } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2497 if (devnull)
2498 fput(devnull);
2499}
2500
2501/*
2502 * Prepare a process for imminent new credential changes due to exec
2503 */
2504static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2505{
2506 struct task_security_struct *new_tsec;
2507 struct rlimit *rlim, *initrlim;
2508 int rc, i;
2509
2510 new_tsec = bprm->cred->security;
2511 if (new_tsec->sid == new_tsec->osid)
2512 return;
2513
2514 /* Close files for which the new task SID is not authorized. */
2515 flush_unauthorized_files(bprm->cred, current->files);
2516
2517 /* Always clear parent death signal on SID transitions. */
2518 current->pdeath_signal = 0;
2519
2520 /* Check whether the new SID can inherit resource limits from the old
2521 * SID. If not, reset all soft limits to the lower of the current
2522 * task's hard limit and the init task's soft limit.
2523 *
2524 * Note that the setting of hard limits (even to lower them) can be
2525 * controlled by the setrlimit check. The inclusion of the init task's
2526 * soft limit into the computation is to avoid resetting soft limits
2527 * higher than the default soft limit for cases where the default is
2528 * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2529 */
2530 rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2531 PROCESS__RLIMITINH, NULL);
2532 if (rc) {
2533 /* protect against do_prlimit() */
2534 task_lock(current);
2535 for (i = 0; i < RLIM_NLIMITS; i++) {
2536 rlim = current->signal->rlim + i;
2537 initrlim = init_task.signal->rlim + i;
2538 rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2539 }
2540 task_unlock(current);
2541 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2542 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2543 }
2544}
2545
2546/*
2547 * Clean up the process immediately after the installation of new credentials
2548 * due to exec
2549 */
2550static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2551{
2552 const struct task_security_struct *tsec = current_security();
2553 struct itimerval itimer;
2554 u32 osid, sid;
2555 int rc, i;
2556
2557 osid = tsec->osid;
2558 sid = tsec->sid;
2559
2560 if (sid == osid)
2561 return;
2562
2563 /* Check whether the new SID can inherit signal state from the old SID.
2564 * If not, clear itimers to avoid subsequent signal generation and
2565 * flush and unblock signals.
2566 *
2567 * This must occur _after_ the task SID has been updated so that any
2568 * kill done after the flush will be checked against the new SID.
2569 */
2570 rc = avc_has_perm(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 match_prefix(char *prefix, int plen, char *option, int olen)
2608{
2609 if (plen > olen)
2610 return 0;
2611
2612 return !memcmp(prefix, option, plen);
2613}
2614
2615static inline int selinux_option(char *option, int len)
2616{
2617 return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2618 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2619 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2620 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2621 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2622}
2623
2624static inline void take_option(char **to, char *from, int *first, int len)
2625{
2626 if (!*first) {
2627 **to = ',';
2628 *to += 1;
2629 } else
2630 *first = 0;
2631 memcpy(*to, from, len);
2632 *to += len;
2633}
2634
2635static inline void take_selinux_option(char **to, char *from, int *first,
2636 int len)
2637{
2638 int current_size = 0;
2639
2640 if (!*first) {
2641 **to = '|';
2642 *to += 1;
2643 } else
2644 *first = 0;
2645
2646 while (current_size < len) {
2647 if (*from != '"') {
2648 **to = *from;
2649 *to += 1;
2650 }
2651 from += 1;
2652 current_size += 1;
2653 }
2654}
2655
2656static int selinux_sb_copy_data(char *orig, char *copy)
2657{
2658 int fnosec, fsec, rc = 0;
2659 char *in_save, *in_curr, *in_end;
2660 char *sec_curr, *nosec_save, *nosec;
2661 int open_quote = 0;
2662
2663 in_curr = orig;
2664 sec_curr = copy;
2665
2666 nosec = (char *)get_zeroed_page(GFP_KERNEL);
2667 if (!nosec) {
2668 rc = -ENOMEM;
2669 goto out;
2670 }
2671
2672 nosec_save = nosec;
2673 fnosec = fsec = 1;
2674 in_save = in_end = orig;
2675
2676 do {
2677 if (*in_end == '"')
2678 open_quote = !open_quote;
2679 if ((*in_end == ',' && open_quote == 0) ||
2680 *in_end == '\0') {
2681 int len = in_end - in_curr;
2682
2683 if (selinux_option(in_curr, len))
2684 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2685 else
2686 take_option(&nosec, in_curr, &fnosec, len);
2687
2688 in_curr = in_end + 1;
2689 }
2690 } while (*in_end++);
2691
2692 strcpy(in_save, nosec_save);
2693 free_page((unsigned long)nosec_save);
2694out:
2695 return rc;
2696}
2697
2698static int selinux_sb_remount(struct super_block *sb, void *data)
2699{
2700 int rc, i, *flags;
2701 struct security_mnt_opts opts;
2702 char *secdata, **mount_options;
2703 struct superblock_security_struct *sbsec = sb->s_security;
2704
2705 if (!(sbsec->flags & SE_SBINITIALIZED))
2706 return 0;
2707
2708 if (!data)
2709 return 0;
2710
2711 if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2712 return 0;
2713
2714 security_init_mnt_opts(&opts);
2715 secdata = alloc_secdata();
2716 if (!secdata)
2717 return -ENOMEM;
2718 rc = selinux_sb_copy_data(data, secdata);
2719 if (rc)
2720 goto out_free_secdata;
2721
2722 rc = selinux_parse_opts_str(secdata, &opts);
2723 if (rc)
2724 goto out_free_secdata;
2725
2726 mount_options = opts.mnt_opts;
2727 flags = opts.mnt_opts_flags;
2728
2729 for (i = 0; i < opts.num_mnt_opts; i++) {
2730 u32 sid;
2731
2732 if (flags[i] == SBLABEL_MNT)
2733 continue;
2734 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2735 if (rc) {
2736 printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2737 "(%s) failed for (dev %s, type %s) errno=%d\n",
2738 mount_options[i], sb->s_id, sb->s_type->name, rc);
2739 goto out_free_opts;
2740 }
2741 rc = -EINVAL;
2742 switch (flags[i]) {
2743 case FSCONTEXT_MNT:
2744 if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2745 goto out_bad_option;
2746 break;
2747 case CONTEXT_MNT:
2748 if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2749 goto out_bad_option;
2750 break;
2751 case ROOTCONTEXT_MNT: {
2752 struct inode_security_struct *root_isec;
2753 root_isec = backing_inode_security(sb->s_root);
2754
2755 if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2756 goto out_bad_option;
2757 break;
2758 }
2759 case DEFCONTEXT_MNT:
2760 if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2761 goto out_bad_option;
2762 break;
2763 default:
2764 goto out_free_opts;
2765 }
2766 }
2767
2768 rc = 0;
2769out_free_opts:
2770 security_free_mnt_opts(&opts);
2771out_free_secdata:
2772 free_secdata(secdata);
2773 return rc;
2774out_bad_option:
2775 printk(KERN_WARNING "SELinux: unable to change security options "
2776 "during remount (dev %s, type=%s)\n", sb->s_id,
2777 sb->s_type->name);
2778 goto out_free_opts;
2779}
2780
2781static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2782{
2783 const struct cred *cred = current_cred();
2784 struct common_audit_data ad;
2785 int rc;
2786
2787 rc = superblock_doinit(sb, data);
2788 if (rc)
2789 return rc;
2790
2791 /* Allow all mounts performed by the kernel */
2792 if (flags & MS_KERNMOUNT)
2793 return 0;
2794
2795 ad.type = LSM_AUDIT_DATA_DENTRY;
2796 ad.u.dentry = sb->s_root;
2797 return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2798}
2799
2800static int selinux_sb_statfs(struct dentry *dentry)
2801{
2802 const struct cred *cred = current_cred();
2803 struct common_audit_data ad;
2804
2805 ad.type = LSM_AUDIT_DATA_DENTRY;
2806 ad.u.dentry = dentry->d_sb->s_root;
2807 return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2808}
2809
2810static int selinux_mount(const char *dev_name,
2811 const struct path *path,
2812 const char *type,
2813 unsigned long flags,
2814 void *data)
2815{
2816 const struct cred *cred = current_cred();
2817
2818 if (flags & MS_REMOUNT)
2819 return superblock_has_perm(cred, path->dentry->d_sb,
2820 FILESYSTEM__REMOUNT, NULL);
2821 else
2822 return path_has_perm(cred, path, FILE__MOUNTON);
2823}
2824
2825static int selinux_umount(struct vfsmount *mnt, int flags)
2826{
2827 const struct cred *cred = current_cred();
2828
2829 return superblock_has_perm(cred, mnt->mnt_sb,
2830 FILESYSTEM__UNMOUNT, NULL);
2831}
2832
2833/* inode security operations */
2834
2835static int selinux_inode_alloc_security(struct inode *inode)
2836{
2837 return inode_alloc_security(inode);
2838}
2839
2840static void selinux_inode_free_security(struct inode *inode)
2841{
2842 inode_free_security(inode);
2843}
2844
2845static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2846 const struct qstr *name, void **ctx,
2847 u32 *ctxlen)
2848{
2849 u32 newsid;
2850 int rc;
2851
2852 rc = selinux_determine_inode_label(current_security(),
2853 d_inode(dentry->d_parent), name,
2854 inode_mode_to_security_class(mode),
2855 &newsid);
2856 if (rc)
2857 return rc;
2858
2859 return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2860}
2861
2862static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2863 struct qstr *name,
2864 const struct cred *old,
2865 struct cred *new)
2866{
2867 u32 newsid;
2868 int rc;
2869 struct task_security_struct *tsec;
2870
2871 rc = selinux_determine_inode_label(old->security,
2872 d_inode(dentry->d_parent), name,
2873 inode_mode_to_security_class(mode),
2874 &newsid);
2875 if (rc)
2876 return rc;
2877
2878 tsec = new->security;
2879 tsec->create_sid = newsid;
2880 return 0;
2881}
2882
2883static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2884 const struct qstr *qstr,
2885 const char **name,
2886 void **value, size_t *len)
2887{
2888 const struct task_security_struct *tsec = current_security();
2889 struct superblock_security_struct *sbsec;
2890 u32 sid, newsid, clen;
2891 int rc;
2892 char *context;
2893
2894 sbsec = dir->i_sb->s_security;
2895
2896 sid = tsec->sid;
2897 newsid = tsec->create_sid;
2898
2899 rc = selinux_determine_inode_label(current_security(),
2900 dir, qstr,
2901 inode_mode_to_security_class(inode->i_mode),
2902 &newsid);
2903 if (rc)
2904 return rc;
2905
2906 /* Possibly defer initialization to selinux_complete_init. */
2907 if (sbsec->flags & SE_SBINITIALIZED) {
2908 struct inode_security_struct *isec = inode->i_security;
2909 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2910 isec->sid = newsid;
2911 isec->initialized = LABEL_INITIALIZED;
2912 }
2913
2914 if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2915 return -EOPNOTSUPP;
2916
2917 if (name)
2918 *name = XATTR_SELINUX_SUFFIX;
2919
2920 if (value && len) {
2921 rc = security_sid_to_context_force(newsid, &context, &clen);
2922 if (rc)
2923 return rc;
2924 *value = context;
2925 *len = clen;
2926 }
2927
2928 return 0;
2929}
2930
2931static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2932{
2933 return may_create(dir, dentry, SECCLASS_FILE);
2934}
2935
2936static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2937{
2938 return may_link(dir, old_dentry, MAY_LINK);
2939}
2940
2941static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2942{
2943 return may_link(dir, dentry, MAY_UNLINK);
2944}
2945
2946static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2947{
2948 return may_create(dir, dentry, SECCLASS_LNK_FILE);
2949}
2950
2951static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2952{
2953 return may_create(dir, dentry, SECCLASS_DIR);
2954}
2955
2956static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2957{
2958 return may_link(dir, dentry, MAY_RMDIR);
2959}
2960
2961static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2962{
2963 return may_create(dir, dentry, inode_mode_to_security_class(mode));
2964}
2965
2966static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2967 struct inode *new_inode, struct dentry *new_dentry)
2968{
2969 return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2970}
2971
2972static int selinux_inode_readlink(struct dentry *dentry)
2973{
2974 const struct cred *cred = current_cred();
2975
2976 return dentry_has_perm(cred, dentry, FILE__READ);
2977}
2978
2979static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2980 bool rcu)
2981{
2982 const struct cred *cred = current_cred();
2983 struct common_audit_data ad;
2984 struct inode_security_struct *isec;
2985 u32 sid;
2986
2987 validate_creds(cred);
2988
2989 ad.type = LSM_AUDIT_DATA_DENTRY;
2990 ad.u.dentry = dentry;
2991 sid = cred_sid(cred);
2992 isec = inode_security_rcu(inode, rcu);
2993 if (IS_ERR(isec))
2994 return PTR_ERR(isec);
2995
2996 return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
2997 rcu ? MAY_NOT_BLOCK : 0);
2998}
2999
3000static noinline int audit_inode_permission(struct inode *inode,
3001 u32 perms, u32 audited, u32 denied,
3002 int result,
3003 unsigned flags)
3004{
3005 struct common_audit_data ad;
3006 struct inode_security_struct *isec = inode->i_security;
3007 int rc;
3008
3009 ad.type = LSM_AUDIT_DATA_INODE;
3010 ad.u.inode = inode;
3011
3012 rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3013 audited, denied, result, &ad, flags);
3014 if (rc)
3015 return rc;
3016 return 0;
3017}
3018
3019static int selinux_inode_permission(struct inode *inode, int mask)
3020{
3021 const struct cred *cred = current_cred();
3022 u32 perms;
3023 bool from_access;
3024 unsigned flags = mask & MAY_NOT_BLOCK;
3025 struct inode_security_struct *isec;
3026 u32 sid;
3027 struct av_decision avd;
3028 int rc, rc2;
3029 u32 audited, denied;
3030
3031 from_access = mask & MAY_ACCESS;
3032 mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3033
3034 /* No permission to check. Existence test. */
3035 if (!mask)
3036 return 0;
3037
3038 validate_creds(cred);
3039
3040 if (unlikely(IS_PRIVATE(inode)))
3041 return 0;
3042
3043 perms = file_mask_to_av(inode->i_mode, mask);
3044
3045 sid = cred_sid(cred);
3046 isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3047 if (IS_ERR(isec))
3048 return PTR_ERR(isec);
3049
3050 rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
3051 audited = avc_audit_required(perms, &avd, rc,
3052 from_access ? FILE__AUDIT_ACCESS : 0,
3053 &denied);
3054 if (likely(!audited))
3055 return rc;
3056
3057 rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3058 if (rc2)
3059 return rc2;
3060 return rc;
3061}
3062
3063static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3064{
3065 const struct cred *cred = current_cred();
3066 unsigned int ia_valid = iattr->ia_valid;
3067 __u32 av = FILE__WRITE;
3068
3069 /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3070 if (ia_valid & ATTR_FORCE) {
3071 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3072 ATTR_FORCE);
3073 if (!ia_valid)
3074 return 0;
3075 }
3076
3077 if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3078 ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3079 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3080
3081 if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
3082 && !(ia_valid & ATTR_FILE))
3083 av |= FILE__OPEN;
3084
3085 return dentry_has_perm(cred, dentry, av);
3086}
3087
3088static int selinux_inode_getattr(const struct path *path)
3089{
3090 return path_has_perm(current_cred(), path, FILE__GETATTR);
3091}
3092
3093static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3094{
3095 const struct cred *cred = current_cred();
3096
3097 if (!strncmp(name, XATTR_SECURITY_PREFIX,
3098 sizeof XATTR_SECURITY_PREFIX - 1)) {
3099 if (!strcmp(name, XATTR_NAME_CAPS)) {
3100 if (!capable(CAP_SETFCAP))
3101 return -EPERM;
3102 } else if (!capable(CAP_SYS_ADMIN)) {
3103 /* A different attribute in the security namespace.
3104 Restrict to administrator. */
3105 return -EPERM;
3106 }
3107 }
3108
3109 /* Not an attribute we recognize, so just check the
3110 ordinary setattr permission. */
3111 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3112}
3113
3114static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115 const void *value, size_t size, int flags)
3116{
3117 struct inode *inode = d_backing_inode(dentry);
3118 struct inode_security_struct *isec;
3119 struct superblock_security_struct *sbsec;
3120 struct common_audit_data ad;
3121 u32 newsid, sid = current_sid();
3122 int rc = 0;
3123
3124 if (strcmp(name, XATTR_NAME_SELINUX))
3125 return selinux_inode_setotherxattr(dentry, name);
3126
3127 sbsec = inode->i_sb->s_security;
3128 if (!(sbsec->flags & SBLABEL_MNT))
3129 return -EOPNOTSUPP;
3130
3131 if (!inode_owner_or_capable(inode))
3132 return -EPERM;
3133
3134 ad.type = LSM_AUDIT_DATA_DENTRY;
3135 ad.u.dentry = dentry;
3136
3137 isec = backing_inode_security(dentry);
3138 rc = avc_has_perm(sid, isec->sid, isec->sclass,
3139 FILE__RELABELFROM, &ad);
3140 if (rc)
3141 return rc;
3142
3143 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3144 if (rc == -EINVAL) {
3145 if (!capable(CAP_MAC_ADMIN)) {
3146 struct audit_buffer *ab;
3147 size_t audit_size;
3148 const char *str;
3149
3150 /* We strip a nul only if it is at the end, otherwise the
3151 * context contains a nul and we should audit that */
3152 if (value) {
3153 str = value;
3154 if (str[size - 1] == '\0')
3155 audit_size = size - 1;
3156 else
3157 audit_size = size;
3158 } else {
3159 str = "";
3160 audit_size = 0;
3161 }
3162 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3163 audit_log_format(ab, "op=setxattr invalid_context=");
3164 audit_log_n_untrustedstring(ab, value, audit_size);
3165 audit_log_end(ab);
3166
3167 return rc;
3168 }
3169 rc = security_context_to_sid_force(value, size, &newsid);
3170 }
3171 if (rc)
3172 return rc;
3173
3174 rc = avc_has_perm(sid, newsid, isec->sclass,
3175 FILE__RELABELTO, &ad);
3176 if (rc)
3177 return rc;
3178
3179 rc = security_validate_transition(isec->sid, newsid, sid,
3180 isec->sclass);
3181 if (rc)
3182 return rc;
3183
3184 return avc_has_perm(newsid,
3185 sbsec->sid,
3186 SECCLASS_FILESYSTEM,
3187 FILESYSTEM__ASSOCIATE,
3188 &ad);
3189}
3190
3191static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3192 const void *value, size_t size,
3193 int flags)
3194{
3195 struct inode *inode = d_backing_inode(dentry);
3196 struct inode_security_struct *isec;
3197 u32 newsid;
3198 int rc;
3199
3200 if (strcmp(name, XATTR_NAME_SELINUX)) {
3201 /* Not an attribute we recognize, so nothing to do. */
3202 return;
3203 }
3204
3205 rc = security_context_to_sid_force(value, size, &newsid);
3206 if (rc) {
3207 printk(KERN_ERR "SELinux: unable to map context to SID"
3208 "for (%s, %lu), rc=%d\n",
3209 inode->i_sb->s_id, inode->i_ino, -rc);
3210 return;
3211 }
3212
3213 isec = backing_inode_security(dentry);
3214 spin_lock(&isec->lock);
3215 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3216 isec->sid = newsid;
3217 isec->initialized = LABEL_INITIALIZED;
3218 spin_unlock(&isec->lock);
3219
3220 return;
3221}
3222
3223static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3224{
3225 const struct cred *cred = current_cred();
3226
3227 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3228}
3229
3230static int selinux_inode_listxattr(struct dentry *dentry)
3231{
3232 const struct cred *cred = current_cred();
3233
3234 return dentry_has_perm(cred, dentry, FILE__GETATTR);
3235}
3236
3237static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3238{
3239 if (strcmp(name, XATTR_NAME_SELINUX))
3240 return selinux_inode_setotherxattr(dentry, name);
3241
3242 /* No one is allowed to remove a SELinux security label.
3243 You can change the label, but all data must be labeled. */
3244 return -EACCES;
3245}
3246
3247/*
3248 * Copy the inode security context value to the user.
3249 *
3250 * Permission check is handled by selinux_inode_getxattr hook.
3251 */
3252static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3253{
3254 u32 size;
3255 int error;
3256 char *context = NULL;
3257 struct inode_security_struct *isec;
3258
3259 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3260 return -EOPNOTSUPP;
3261
3262 /*
3263 * If the caller has CAP_MAC_ADMIN, then get the raw context
3264 * value even if it is not defined by current policy; otherwise,
3265 * use the in-core value under current policy.
3266 * Use the non-auditing forms of the permission checks since
3267 * getxattr may be called by unprivileged processes commonly
3268 * and lack of permission just means that we fall back to the
3269 * in-core context value, not a denial.
3270 */
3271 error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3272 SECURITY_CAP_NOAUDIT);
3273 if (!error)
3274 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
3275 SECURITY_CAP_NOAUDIT, true);
3276 isec = inode_security(inode);
3277 if (!error)
3278 error = security_sid_to_context_force(isec->sid, &context,
3279 &size);
3280 else
3281 error = security_sid_to_context(isec->sid, &context, &size);
3282 if (error)
3283 return error;
3284 error = size;
3285 if (alloc) {
3286 *buffer = context;
3287 goto out_nofree;
3288 }
3289 kfree(context);
3290out_nofree:
3291 return error;
3292}
3293
3294static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3295 const void *value, size_t size, int flags)
3296{
3297 struct inode_security_struct *isec = inode_security_novalidate(inode);
3298 u32 newsid;
3299 int rc;
3300
3301 if (strcmp(name, XATTR_SELINUX_SUFFIX))
3302 return -EOPNOTSUPP;
3303
3304 if (!value || !size)
3305 return -EACCES;
3306
3307 rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3308 if (rc)
3309 return rc;
3310
3311 spin_lock(&isec->lock);
3312 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3313 isec->sid = newsid;
3314 isec->initialized = LABEL_INITIALIZED;
3315 spin_unlock(&isec->lock);
3316 return 0;
3317}
3318
3319static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3320{
3321 const int len = sizeof(XATTR_NAME_SELINUX);
3322 if (buffer && len <= buffer_size)
3323 memcpy(buffer, XATTR_NAME_SELINUX, len);
3324 return len;
3325}
3326
3327static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3328{
3329 struct inode_security_struct *isec = inode_security_novalidate(inode);
3330 *secid = isec->sid;
3331}
3332
3333static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3334{
3335 u32 sid;
3336 struct task_security_struct *tsec;
3337 struct cred *new_creds = *new;
3338
3339 if (new_creds == NULL) {
3340 new_creds = prepare_creds();
3341 if (!new_creds)
3342 return -ENOMEM;
3343 }
3344
3345 tsec = new_creds->security;
3346 /* Get label from overlay inode and set it in create_sid */
3347 selinux_inode_getsecid(d_inode(src), &sid);
3348 tsec->create_sid = sid;
3349 *new = new_creds;
3350 return 0;
3351}
3352
3353static int selinux_inode_copy_up_xattr(const char *name)
3354{
3355 /* The copy_up hook above sets the initial context on an inode, but we
3356 * don't then want to overwrite it by blindly copying all the lower
3357 * xattrs up. Instead, we have to filter out SELinux-related xattrs.
3358 */
3359 if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3360 return 1; /* Discard */
3361 /*
3362 * Any other attribute apart from SELINUX is not claimed, supported
3363 * by selinux.
3364 */
3365 return -EOPNOTSUPP;
3366}
3367
3368/* file security operations */
3369
3370static int selinux_revalidate_file_permission(struct file *file, int mask)
3371{
3372 const struct cred *cred = current_cred();
3373 struct inode *inode = file_inode(file);
3374
3375 /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3376 if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3377 mask |= MAY_APPEND;
3378
3379 return file_has_perm(cred, file,
3380 file_mask_to_av(inode->i_mode, mask));
3381}
3382
3383static int selinux_file_permission(struct file *file, int mask)
3384{
3385 struct inode *inode = file_inode(file);
3386 struct file_security_struct *fsec = file->f_security;
3387 struct inode_security_struct *isec;
3388 u32 sid = current_sid();
3389
3390 if (!mask)
3391 /* No permission to check. Existence test. */
3392 return 0;
3393
3394 isec = inode_security(inode);
3395 if (sid == fsec->sid && fsec->isid == isec->sid &&
3396 fsec->pseqno == avc_policy_seqno())
3397 /* No change since file_open check. */
3398 return 0;
3399
3400 return selinux_revalidate_file_permission(file, mask);
3401}
3402
3403static int selinux_file_alloc_security(struct file *file)
3404{
3405 return file_alloc_security(file);
3406}
3407
3408static void selinux_file_free_security(struct file *file)
3409{
3410 file_free_security(file);
3411}
3412
3413/*
3414 * Check whether a task has the ioctl permission and cmd
3415 * operation to an inode.
3416 */
3417static int ioctl_has_perm(const struct cred *cred, struct file *file,
3418 u32 requested, u16 cmd)
3419{
3420 struct common_audit_data ad;
3421 struct file_security_struct *fsec = file->f_security;
3422 struct inode *inode = file_inode(file);
3423 struct inode_security_struct *isec;
3424 struct lsm_ioctlop_audit ioctl;
3425 u32 ssid = cred_sid(cred);
3426 int rc;
3427 u8 driver = cmd >> 8;
3428 u8 xperm = cmd & 0xff;
3429
3430 ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3431 ad.u.op = &ioctl;
3432 ad.u.op->cmd = cmd;
3433 ad.u.op->path = file->f_path;
3434
3435 if (ssid != fsec->sid) {
3436 rc = avc_has_perm(ssid, fsec->sid,
3437 SECCLASS_FD,
3438 FD__USE,
3439 &ad);
3440 if (rc)
3441 goto out;
3442 }
3443
3444 if (unlikely(IS_PRIVATE(inode)))
3445 return 0;
3446
3447 isec = inode_security(inode);
3448 rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3449 requested, driver, xperm, &ad);
3450out:
3451 return rc;
3452}
3453
3454static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3455 unsigned long arg)
3456{
3457 const struct cred *cred = current_cred();
3458 int error = 0;
3459
3460 switch (cmd) {
3461 case FIONREAD:
3462 /* fall through */
3463 case FIBMAP:
3464 /* fall through */
3465 case FIGETBSZ:
3466 /* fall through */
3467 case FS_IOC_GETFLAGS:
3468 /* fall through */
3469 case FS_IOC_GETVERSION:
3470 error = file_has_perm(cred, file, FILE__GETATTR);
3471 break;
3472
3473 case FS_IOC_SETFLAGS:
3474 /* fall through */
3475 case FS_IOC_SETVERSION:
3476 error = file_has_perm(cred, file, FILE__SETATTR);
3477 break;
3478
3479 /* sys_ioctl() checks */
3480 case FIONBIO:
3481 /* fall through */
3482 case FIOASYNC:
3483 error = file_has_perm(cred, file, 0);
3484 break;
3485
3486 case KDSKBENT:
3487 case KDSKBSENT:
3488 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3489 SECURITY_CAP_AUDIT, true);
3490 break;
3491
3492 /* default case assumes that the command will go
3493 * to the file's ioctl() function.
3494 */
3495 default:
3496 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3497 }
3498 return error;
3499}
3500
3501static int default_noexec;
3502
3503static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3504{
3505 const struct cred *cred = current_cred();
3506 int rc = 0;
3507
3508 if (default_noexec &&
3509 (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3510 (!shared && (prot & PROT_WRITE)))) {
3511 /*
3512 * We are making executable an anonymous mapping or a
3513 * private file mapping that will also be writable.
3514 * This has an additional check.
3515 */
3516 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3517 if (rc)
3518 goto error;
3519 }
3520
3521 if (file) {
3522 /* read access is always possible with a mapping */
3523 u32 av = FILE__READ;
3524
3525 /* write access only matters if the mapping is shared */
3526 if (shared && (prot & PROT_WRITE))
3527 av |= FILE__WRITE;
3528
3529 if (prot & PROT_EXEC)
3530 av |= FILE__EXECUTE;
3531
3532 return file_has_perm(cred, file, av);
3533 }
3534
3535error:
3536 return rc;
3537}
3538
3539static int selinux_mmap_addr(unsigned long addr)
3540{
3541 int rc = 0;
3542
3543 if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3544 u32 sid = current_sid();
3545 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3546 MEMPROTECT__MMAP_ZERO, NULL);
3547 }
3548
3549 return rc;
3550}
3551
3552static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3553 unsigned long prot, unsigned long flags)
3554{
3555 if (selinux_checkreqprot)
3556 prot = reqprot;
3557
3558 return file_map_prot_check(file, prot,
3559 (flags & MAP_TYPE) == MAP_SHARED);
3560}
3561
3562static int selinux_file_mprotect(struct vm_area_struct *vma,
3563 unsigned long reqprot,
3564 unsigned long prot)
3565{
3566 const struct cred *cred = current_cred();
3567
3568 if (selinux_checkreqprot)
3569 prot = reqprot;
3570
3571 if (default_noexec &&
3572 (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3573 int rc = 0;
3574 if (vma->vm_start >= vma->vm_mm->start_brk &&
3575 vma->vm_end <= vma->vm_mm->brk) {
3576 rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3577 } else if (!vma->vm_file &&
3578 ((vma->vm_start <= vma->vm_mm->start_stack &&
3579 vma->vm_end >= vma->vm_mm->start_stack) ||
3580 vma_is_stack_for_current(vma))) {
3581 rc = current_has_perm(current, PROCESS__EXECSTACK);
3582 } else if (vma->vm_file && vma->anon_vma) {
3583 /*
3584 * We are making executable a file mapping that has
3585 * had some COW done. Since pages might have been
3586 * written, check ability to execute the possibly
3587 * modified content. This typically should only
3588 * occur for text relocations.
3589 */
3590 rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3591 }
3592 if (rc)
3593 return rc;
3594 }
3595
3596 return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3597}
3598
3599static int selinux_file_lock(struct file *file, unsigned int cmd)
3600{
3601 const struct cred *cred = current_cred();
3602
3603 return file_has_perm(cred, file, FILE__LOCK);
3604}
3605
3606static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3607 unsigned long arg)
3608{
3609 const struct cred *cred = current_cred();
3610 int err = 0;
3611
3612 switch (cmd) {
3613 case F_SETFL:
3614 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3615 err = file_has_perm(cred, file, FILE__WRITE);
3616 break;
3617 }
3618 /* fall through */
3619 case F_SETOWN:
3620 case F_SETSIG:
3621 case F_GETFL:
3622 case F_GETOWN:
3623 case F_GETSIG:
3624 case F_GETOWNER_UIDS:
3625 /* Just check FD__USE permission */
3626 err = file_has_perm(cred, file, 0);
3627 break;
3628 case F_GETLK:
3629 case F_SETLK:
3630 case F_SETLKW:
3631 case F_OFD_GETLK:
3632 case F_OFD_SETLK:
3633 case F_OFD_SETLKW:
3634#if BITS_PER_LONG == 32
3635 case F_GETLK64:
3636 case F_SETLK64:
3637 case F_SETLKW64:
3638#endif
3639 err = file_has_perm(cred, file, FILE__LOCK);
3640 break;
3641 }
3642
3643 return err;
3644}
3645
3646static void selinux_file_set_fowner(struct file *file)
3647{
3648 struct file_security_struct *fsec;
3649
3650 fsec = file->f_security;
3651 fsec->fown_sid = current_sid();
3652}
3653
3654static int selinux_file_send_sigiotask(struct task_struct *tsk,
3655 struct fown_struct *fown, int signum)
3656{
3657 struct file *file;
3658 u32 sid = task_sid(tsk);
3659 u32 perm;
3660 struct file_security_struct *fsec;
3661
3662 /* struct fown_struct is never outside the context of a struct file */
3663 file = container_of(fown, struct file, f_owner);
3664
3665 fsec = file->f_security;
3666
3667 if (!signum)
3668 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3669 else
3670 perm = signal_to_av(signum);
3671
3672 return avc_has_perm(fsec->fown_sid, sid,
3673 SECCLASS_PROCESS, perm, NULL);
3674}
3675
3676static int selinux_file_receive(struct file *file)
3677{
3678 const struct cred *cred = current_cred();
3679
3680 return file_has_perm(cred, file, file_to_av(file));
3681}
3682
3683static int selinux_file_open(struct file *file, const struct cred *cred)
3684{
3685 struct file_security_struct *fsec;
3686 struct inode_security_struct *isec;
3687
3688 fsec = file->f_security;
3689 isec = inode_security(file_inode(file));
3690 /*
3691 * Save inode label and policy sequence number
3692 * at open-time so that selinux_file_permission
3693 * can determine whether revalidation is necessary.
3694 * Task label is already saved in the file security
3695 * struct as its SID.
3696 */
3697 fsec->isid = isec->sid;
3698 fsec->pseqno = avc_policy_seqno();
3699 /*
3700 * Since the inode label or policy seqno may have changed
3701 * between the selinux_inode_permission check and the saving
3702 * of state above, recheck that access is still permitted.
3703 * Otherwise, access might never be revalidated against the
3704 * new inode label or new policy.
3705 * This check is not redundant - do not remove.
3706 */
3707 return file_path_has_perm(cred, file, open_file_to_av(file));
3708}
3709
3710/* task security operations */
3711
3712static int selinux_task_create(unsigned long clone_flags)
3713{
3714 return current_has_perm(current, PROCESS__FORK);
3715}
3716
3717/*
3718 * allocate the SELinux part of blank credentials
3719 */
3720static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3721{
3722 struct task_security_struct *tsec;
3723
3724 tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3725 if (!tsec)
3726 return -ENOMEM;
3727
3728 cred->security = tsec;
3729 return 0;
3730}
3731
3732/*
3733 * detach and free the LSM part of a set of credentials
3734 */
3735static void selinux_cred_free(struct cred *cred)
3736{
3737 struct task_security_struct *tsec = cred->security;
3738
3739 /*
3740 * cred->security == NULL if security_cred_alloc_blank() or
3741 * security_prepare_creds() returned an error.
3742 */
3743 BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3744 cred->security = (void *) 0x7UL;
3745 kfree(tsec);
3746}
3747
3748/*
3749 * prepare a new set of credentials for modification
3750 */
3751static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3752 gfp_t gfp)
3753{
3754 const struct task_security_struct *old_tsec;
3755 struct task_security_struct *tsec;
3756
3757 old_tsec = old->security;
3758
3759 tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3760 if (!tsec)
3761 return -ENOMEM;
3762
3763 new->security = tsec;
3764 return 0;
3765}
3766
3767/*
3768 * transfer the SELinux data to a blank set of creds
3769 */
3770static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3771{
3772 const struct task_security_struct *old_tsec = old->security;
3773 struct task_security_struct *tsec = new->security;
3774
3775 *tsec = *old_tsec;
3776}
3777
3778/*
3779 * set the security data for a kernel service
3780 * - all the creation contexts are set to unlabelled
3781 */
3782static int selinux_kernel_act_as(struct cred *new, u32 secid)
3783{
3784 struct task_security_struct *tsec = new->security;
3785 u32 sid = current_sid();
3786 int ret;
3787
3788 ret = avc_has_perm(sid, secid,
3789 SECCLASS_KERNEL_SERVICE,
3790 KERNEL_SERVICE__USE_AS_OVERRIDE,
3791 NULL);
3792 if (ret == 0) {
3793 tsec->sid = secid;
3794 tsec->create_sid = 0;
3795 tsec->keycreate_sid = 0;
3796 tsec->sockcreate_sid = 0;
3797 }
3798 return ret;
3799}
3800
3801/*
3802 * set the file creation context in a security record to the same as the
3803 * objective context of the specified inode
3804 */
3805static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3806{
3807 struct inode_security_struct *isec = inode_security(inode);
3808 struct task_security_struct *tsec = new->security;
3809 u32 sid = current_sid();
3810 int ret;
3811
3812 ret = avc_has_perm(sid, isec->sid,
3813 SECCLASS_KERNEL_SERVICE,
3814 KERNEL_SERVICE__CREATE_FILES_AS,
3815 NULL);
3816
3817 if (ret == 0)
3818 tsec->create_sid = isec->sid;
3819 return ret;
3820}
3821
3822static int selinux_kernel_module_request(char *kmod_name)
3823{
3824 u32 sid;
3825 struct common_audit_data ad;
3826
3827 sid = task_sid(current);
3828
3829 ad.type = LSM_AUDIT_DATA_KMOD;
3830 ad.u.kmod_name = kmod_name;
3831
3832 return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3833 SYSTEM__MODULE_REQUEST, &ad);
3834}
3835
3836static int selinux_kernel_module_from_file(struct file *file)
3837{
3838 struct common_audit_data ad;
3839 struct inode_security_struct *isec;
3840 struct file_security_struct *fsec;
3841 u32 sid = current_sid();
3842 int rc;
3843
3844 /* init_module */
3845 if (file == NULL)
3846 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
3847 SYSTEM__MODULE_LOAD, NULL);
3848
3849 /* finit_module */
3850
3851 ad.type = LSM_AUDIT_DATA_FILE;
3852 ad.u.file = file;
3853
3854 fsec = file->f_security;
3855 if (sid != fsec->sid) {
3856 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3857 if (rc)
3858 return rc;
3859 }
3860
3861 isec = inode_security(file_inode(file));
3862 return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
3863 SYSTEM__MODULE_LOAD, &ad);
3864}
3865
3866static int selinux_kernel_read_file(struct file *file,
3867 enum kernel_read_file_id id)
3868{
3869 int rc = 0;
3870
3871 switch (id) {
3872 case READING_MODULE:
3873 rc = selinux_kernel_module_from_file(file);
3874 break;
3875 default:
3876 break;
3877 }
3878
3879 return rc;
3880}
3881
3882static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3883{
3884 return current_has_perm(p, PROCESS__SETPGID);
3885}
3886
3887static int selinux_task_getpgid(struct task_struct *p)
3888{
3889 return current_has_perm(p, PROCESS__GETPGID);
3890}
3891
3892static int selinux_task_getsid(struct task_struct *p)
3893{
3894 return current_has_perm(p, PROCESS__GETSESSION);
3895}
3896
3897static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3898{
3899 *secid = task_sid(p);
3900}
3901
3902static int selinux_task_setnice(struct task_struct *p, int nice)
3903{
3904 return current_has_perm(p, PROCESS__SETSCHED);
3905}
3906
3907static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3908{
3909 return current_has_perm(p, PROCESS__SETSCHED);
3910}
3911
3912static int selinux_task_getioprio(struct task_struct *p)
3913{
3914 return current_has_perm(p, PROCESS__GETSCHED);
3915}
3916
3917static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3918 struct rlimit *new_rlim)
3919{
3920 struct rlimit *old_rlim = p->signal->rlim + resource;
3921
3922 /* Control the ability to change the hard limit (whether
3923 lowering or raising it), so that the hard limit can
3924 later be used as a safe reset point for the soft limit
3925 upon context transitions. See selinux_bprm_committing_creds. */
3926 if (old_rlim->rlim_max != new_rlim->rlim_max)
3927 return current_has_perm(p, PROCESS__SETRLIMIT);
3928
3929 return 0;
3930}
3931
3932static int selinux_task_setscheduler(struct task_struct *p)
3933{
3934 return current_has_perm(p, PROCESS__SETSCHED);
3935}
3936
3937static int selinux_task_getscheduler(struct task_struct *p)
3938{
3939 return current_has_perm(p, PROCESS__GETSCHED);
3940}
3941
3942static int selinux_task_movememory(struct task_struct *p)
3943{
3944 return current_has_perm(p, PROCESS__SETSCHED);
3945}
3946
3947static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3948 int sig, u32 secid)
3949{
3950 u32 perm;
3951 int rc;
3952
3953 if (!sig)
3954 perm = PROCESS__SIGNULL; /* null signal; existence test */
3955 else
3956 perm = signal_to_av(sig);
3957 if (secid)
3958 rc = avc_has_perm(secid, task_sid(p),
3959 SECCLASS_PROCESS, perm, NULL);
3960 else
3961 rc = current_has_perm(p, perm);
3962 return rc;
3963}
3964
3965static int selinux_task_wait(struct task_struct *p)
3966{
3967 return task_has_perm(p, current, PROCESS__SIGCHLD);
3968}
3969
3970static void selinux_task_to_inode(struct task_struct *p,
3971 struct inode *inode)
3972{
3973 struct inode_security_struct *isec = inode->i_security;
3974 u32 sid = task_sid(p);
3975
3976 spin_lock(&isec->lock);
3977 isec->sclass = inode_mode_to_security_class(inode->i_mode);
3978 isec->sid = sid;
3979 isec->initialized = LABEL_INITIALIZED;
3980 spin_unlock(&isec->lock);
3981}
3982
3983/* Returns error only if unable to parse addresses */
3984static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3985 struct common_audit_data *ad, u8 *proto)
3986{
3987 int offset, ihlen, ret = -EINVAL;
3988 struct iphdr _iph, *ih;
3989
3990 offset = skb_network_offset(skb);
3991 ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3992 if (ih == NULL)
3993 goto out;
3994
3995 ihlen = ih->ihl * 4;
3996 if (ihlen < sizeof(_iph))
3997 goto out;
3998
3999 ad->u.net->v4info.saddr = ih->saddr;
4000 ad->u.net->v4info.daddr = ih->daddr;
4001 ret = 0;
4002
4003 if (proto)
4004 *proto = ih->protocol;
4005
4006 switch (ih->protocol) {
4007 case IPPROTO_TCP: {
4008 struct tcphdr _tcph, *th;
4009
4010 if (ntohs(ih->frag_off) & IP_OFFSET)
4011 break;
4012
4013 offset += ihlen;
4014 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4015 if (th == NULL)
4016 break;
4017
4018 ad->u.net->sport = th->source;
4019 ad->u.net->dport = th->dest;
4020 break;
4021 }
4022
4023 case IPPROTO_UDP: {
4024 struct udphdr _udph, *uh;
4025
4026 if (ntohs(ih->frag_off) & IP_OFFSET)
4027 break;
4028
4029 offset += ihlen;
4030 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4031 if (uh == NULL)
4032 break;
4033
4034 ad->u.net->sport = uh->source;
4035 ad->u.net->dport = uh->dest;
4036 break;
4037 }
4038
4039 case IPPROTO_DCCP: {
4040 struct dccp_hdr _dccph, *dh;
4041
4042 if (ntohs(ih->frag_off) & IP_OFFSET)
4043 break;
4044
4045 offset += ihlen;
4046 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4047 if (dh == NULL)
4048 break;
4049
4050 ad->u.net->sport = dh->dccph_sport;
4051 ad->u.net->dport = dh->dccph_dport;
4052 break;
4053 }
4054
4055 default:
4056 break;
4057 }
4058out:
4059 return ret;
4060}
4061
4062#if IS_ENABLED(CONFIG_IPV6)
4063
4064/* Returns error only if unable to parse addresses */
4065static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4066 struct common_audit_data *ad, u8 *proto)
4067{
4068 u8 nexthdr;
4069 int ret = -EINVAL, offset;
4070 struct ipv6hdr _ipv6h, *ip6;
4071 __be16 frag_off;
4072
4073 offset = skb_network_offset(skb);
4074 ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4075 if (ip6 == NULL)
4076 goto out;
4077
4078 ad->u.net->v6info.saddr = ip6->saddr;
4079 ad->u.net->v6info.daddr = ip6->daddr;
4080 ret = 0;
4081
4082 nexthdr = ip6->nexthdr;
4083 offset += sizeof(_ipv6h);
4084 offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4085 if (offset < 0)
4086 goto out;
4087
4088 if (proto)
4089 *proto = nexthdr;
4090
4091 switch (nexthdr) {
4092 case IPPROTO_TCP: {
4093 struct tcphdr _tcph, *th;
4094
4095 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4096 if (th == NULL)
4097 break;
4098
4099 ad->u.net->sport = th->source;
4100 ad->u.net->dport = th->dest;
4101 break;
4102 }
4103
4104 case IPPROTO_UDP: {
4105 struct udphdr _udph, *uh;
4106
4107 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4108 if (uh == NULL)
4109 break;
4110
4111 ad->u.net->sport = uh->source;
4112 ad->u.net->dport = uh->dest;
4113 break;
4114 }
4115
4116 case IPPROTO_DCCP: {
4117 struct dccp_hdr _dccph, *dh;
4118
4119 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4120 if (dh == NULL)
4121 break;
4122
4123 ad->u.net->sport = dh->dccph_sport;
4124 ad->u.net->dport = dh->dccph_dport;
4125 break;
4126 }
4127
4128 /* includes fragments */
4129 default:
4130 break;
4131 }
4132out:
4133 return ret;
4134}
4135
4136#endif /* IPV6 */
4137
4138static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4139 char **_addrp, int src, u8 *proto)
4140{
4141 char *addrp;
4142 int ret;
4143
4144 switch (ad->u.net->family) {
4145 case PF_INET:
4146 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4147 if (ret)
4148 goto parse_error;
4149 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4150 &ad->u.net->v4info.daddr);
4151 goto okay;
4152
4153#if IS_ENABLED(CONFIG_IPV6)
4154 case PF_INET6:
4155 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4156 if (ret)
4157 goto parse_error;
4158 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4159 &ad->u.net->v6info.daddr);
4160 goto okay;
4161#endif /* IPV6 */
4162 default:
4163 addrp = NULL;
4164 goto okay;
4165 }
4166
4167parse_error:
4168 printk(KERN_WARNING
4169 "SELinux: failure in selinux_parse_skb(),"
4170 " unable to parse packet\n");
4171 return ret;
4172
4173okay:
4174 if (_addrp)
4175 *_addrp = addrp;
4176 return 0;
4177}
4178
4179/**
4180 * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4181 * @skb: the packet
4182 * @family: protocol family
4183 * @sid: the packet's peer label SID
4184 *
4185 * Description:
4186 * Check the various different forms of network peer labeling and determine
4187 * the peer label/SID for the packet; most of the magic actually occurs in
4188 * the security server function security_net_peersid_cmp(). The function
4189 * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4190 * or -EACCES if @sid is invalid due to inconsistencies with the different
4191 * peer labels.
4192 *
4193 */
4194static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4195{
4196 int err;
4197 u32 xfrm_sid;
4198 u32 nlbl_sid;
4199 u32 nlbl_type;
4200
4201 err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4202 if (unlikely(err))
4203 return -EACCES;
4204 err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4205 if (unlikely(err))
4206 return -EACCES;
4207
4208 err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
4209 if (unlikely(err)) {
4210 printk(KERN_WARNING
4211 "SELinux: failure in selinux_skb_peerlbl_sid(),"
4212 " unable to determine packet's peer label\n");
4213 return -EACCES;
4214 }
4215
4216 return 0;
4217}
4218
4219/**
4220 * selinux_conn_sid - Determine the child socket label for a connection
4221 * @sk_sid: the parent socket's SID
4222 * @skb_sid: the packet's SID
4223 * @conn_sid: the resulting connection SID
4224 *
4225 * If @skb_sid is valid then the user:role:type information from @sk_sid is
4226 * combined with the MLS information from @skb_sid in order to create
4227 * @conn_sid. If @skb_sid is not valid then then @conn_sid is simply a copy
4228 * of @sk_sid. Returns zero on success, negative values on failure.
4229 *
4230 */
4231static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4232{
4233 int err = 0;
4234
4235 if (skb_sid != SECSID_NULL)
4236 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
4237 else
4238 *conn_sid = sk_sid;
4239
4240 return err;
4241}
4242
4243/* socket security operations */
4244
4245static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4246 u16 secclass, u32 *socksid)
4247{
4248 if (tsec->sockcreate_sid > SECSID_NULL) {
4249 *socksid = tsec->sockcreate_sid;
4250 return 0;
4251 }
4252
4253 return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4254 socksid);
4255}
4256
4257static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4258{
4259 struct sk_security_struct *sksec = sk->sk_security;
4260 struct common_audit_data ad;
4261 struct lsm_network_audit net = {0,};
4262 u32 tsid = task_sid(task);
4263
4264 if (sksec->sid == SECINITSID_KERNEL)
4265 return 0;
4266
4267 ad.type = LSM_AUDIT_DATA_NET;
4268 ad.u.net = &net;
4269 ad.u.net->sk = sk;
4270
4271 return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4272}
4273
4274static int selinux_socket_create(int family, int type,
4275 int protocol, int kern)
4276{
4277 const struct task_security_struct *tsec = current_security();
4278 u32 newsid;
4279 u16 secclass;
4280 int rc;
4281
4282 if (kern)
4283 return 0;
4284
4285 secclass = socket_type_to_security_class(family, type, protocol);
4286 rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4287 if (rc)
4288 return rc;
4289
4290 return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4291}
4292
4293static int selinux_socket_post_create(struct socket *sock, int family,
4294 int type, int protocol, int kern)
4295{
4296 const struct task_security_struct *tsec = current_security();
4297 struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4298 struct sk_security_struct *sksec;
4299 u16 sclass = socket_type_to_security_class(family, type, protocol);
4300 u32 sid = SECINITSID_KERNEL;
4301 int err = 0;
4302
4303 if (!kern) {
4304 err = socket_sockcreate_sid(tsec, sclass, &sid);
4305 if (err)
4306 return err;
4307 }
4308
4309 isec->sclass = sclass;
4310 isec->sid = sid;
4311 isec->initialized = LABEL_INITIALIZED;
4312
4313 if (sock->sk) {
4314 sksec = sock->sk->sk_security;
4315 sksec->sclass = sclass;
4316 sksec->sid = sid;
4317 err = selinux_netlbl_socket_post_create(sock->sk, family);
4318 }
4319
4320 return err;
4321}
4322
4323/* Range of port numbers used to automatically bind.
4324 Need to determine whether we should perform a name_bind
4325 permission check between the socket and the port number. */
4326
4327static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4328{
4329 struct sock *sk = sock->sk;
4330 u16 family;
4331 int err;
4332
4333 err = sock_has_perm(current, sk, SOCKET__BIND);
4334 if (err)
4335 goto out;
4336
4337 /*
4338 * If PF_INET or PF_INET6, check name_bind permission for the port.
4339 * Multiple address binding for SCTP is not supported yet: we just
4340 * check the first address now.
4341 */
4342 family = sk->sk_family;
4343 if (family == PF_INET || family == PF_INET6) {
4344 char *addrp;
4345 struct sk_security_struct *sksec = sk->sk_security;
4346 struct common_audit_data ad;
4347 struct lsm_network_audit net = {0,};
4348 struct sockaddr_in *addr4 = NULL;
4349 struct sockaddr_in6 *addr6 = NULL;
4350 unsigned short snum;
4351 u32 sid, node_perm;
4352
4353 if (family == PF_INET) {
4354 addr4 = (struct sockaddr_in *)address;
4355 snum = ntohs(addr4->sin_port);
4356 addrp = (char *)&addr4->sin_addr.s_addr;
4357 } else {
4358 addr6 = (struct sockaddr_in6 *)address;
4359 snum = ntohs(addr6->sin6_port);
4360 addrp = (char *)&addr6->sin6_addr.s6_addr;
4361 }
4362
4363 if (snum) {
4364 int low, high;
4365
4366 inet_get_local_port_range(sock_net(sk), &low, &high);
4367
4368 if (snum < max(PROT_SOCK, low) || snum > high) {
4369 err = sel_netport_sid(sk->sk_protocol,
4370 snum, &sid);
4371 if (err)
4372 goto out;
4373 ad.type = LSM_AUDIT_DATA_NET;
4374 ad.u.net = &net;
4375 ad.u.net->sport = htons(snum);
4376 ad.u.net->family = family;
4377 err = avc_has_perm(sksec->sid, sid,
4378 sksec->sclass,
4379 SOCKET__NAME_BIND, &ad);
4380 if (err)
4381 goto out;
4382 }
4383 }
4384
4385 switch (sksec->sclass) {
4386 case SECCLASS_TCP_SOCKET:
4387 node_perm = TCP_SOCKET__NODE_BIND;
4388 break;
4389
4390 case SECCLASS_UDP_SOCKET:
4391 node_perm = UDP_SOCKET__NODE_BIND;
4392 break;
4393
4394 case SECCLASS_DCCP_SOCKET:
4395 node_perm = DCCP_SOCKET__NODE_BIND;
4396 break;
4397
4398 default:
4399 node_perm = RAWIP_SOCKET__NODE_BIND;
4400 break;
4401 }
4402
4403 err = sel_netnode_sid(addrp, family, &sid);
4404 if (err)
4405 goto out;
4406
4407 ad.type = LSM_AUDIT_DATA_NET;
4408 ad.u.net = &net;
4409 ad.u.net->sport = htons(snum);
4410 ad.u.net->family = family;
4411
4412 if (family == PF_INET)
4413 ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4414 else
4415 ad.u.net->v6info.saddr = addr6->sin6_addr;
4416
4417 err = avc_has_perm(sksec->sid, sid,
4418 sksec->sclass, node_perm, &ad);
4419 if (err)
4420 goto out;
4421 }
4422out:
4423 return err;
4424}
4425
4426static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4427{
4428 struct sock *sk = sock->sk;
4429 struct sk_security_struct *sksec = sk->sk_security;
4430 int err;
4431
4432 err = sock_has_perm(current, sk, SOCKET__CONNECT);
4433 if (err)
4434 return err;
4435
4436 /*
4437 * If a TCP or DCCP socket, check name_connect permission for the port.
4438 */
4439 if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4440 sksec->sclass == SECCLASS_DCCP_SOCKET) {
4441 struct common_audit_data ad;
4442 struct lsm_network_audit net = {0,};
4443 struct sockaddr_in *addr4 = NULL;
4444 struct sockaddr_in6 *addr6 = NULL;
4445 unsigned short snum;
4446 u32 sid, perm;
4447
4448 if (sk->sk_family == PF_INET) {
4449 addr4 = (struct sockaddr_in *)address;
4450 if (addrlen < sizeof(struct sockaddr_in))
4451 return -EINVAL;
4452 snum = ntohs(addr4->sin_port);
4453 } else {
4454 addr6 = (struct sockaddr_in6 *)address;
4455 if (addrlen < SIN6_LEN_RFC2133)
4456 return -EINVAL;
4457 snum = ntohs(addr6->sin6_port);
4458 }
4459
4460 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4461 if (err)
4462 goto out;
4463
4464 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4465 TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4466
4467 ad.type = LSM_AUDIT_DATA_NET;
4468 ad.u.net = &net;
4469 ad.u.net->dport = htons(snum);
4470 ad.u.net->family = sk->sk_family;
4471 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4472 if (err)
4473 goto out;
4474 }
4475
4476 err = selinux_netlbl_socket_connect(sk, address);
4477
4478out:
4479 return err;
4480}
4481
4482static int selinux_socket_listen(struct socket *sock, int backlog)
4483{
4484 return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4485}
4486
4487static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4488{
4489 int err;
4490 struct inode_security_struct *isec;
4491 struct inode_security_struct *newisec;
4492 u16 sclass;
4493 u32 sid;
4494
4495 err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4496 if (err)
4497 return err;
4498
4499 isec = inode_security_novalidate(SOCK_INODE(sock));
4500 spin_lock(&isec->lock);
4501 sclass = isec->sclass;
4502 sid = isec->sid;
4503 spin_unlock(&isec->lock);
4504
4505 newisec = inode_security_novalidate(SOCK_INODE(newsock));
4506 newisec->sclass = sclass;
4507 newisec->sid = sid;
4508 newisec->initialized = LABEL_INITIALIZED;
4509
4510 return 0;
4511}
4512
4513static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4514 int size)
4515{
4516 return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4517}
4518
4519static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4520 int size, int flags)
4521{
4522 return sock_has_perm(current, sock->sk, SOCKET__READ);
4523}
4524
4525static int selinux_socket_getsockname(struct socket *sock)
4526{
4527 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4528}
4529
4530static int selinux_socket_getpeername(struct socket *sock)
4531{
4532 return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4533}
4534
4535static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4536{
4537 int err;
4538
4539 err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4540 if (err)
4541 return err;
4542
4543 return selinux_netlbl_socket_setsockopt(sock, level, optname);
4544}
4545
4546static int selinux_socket_getsockopt(struct socket *sock, int level,
4547 int optname)
4548{
4549 return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4550}
4551
4552static int selinux_socket_shutdown(struct socket *sock, int how)
4553{
4554 return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4555}
4556
4557static int selinux_socket_unix_stream_connect(struct sock *sock,
4558 struct sock *other,
4559 struct sock *newsk)
4560{
4561 struct sk_security_struct *sksec_sock = sock->sk_security;
4562 struct sk_security_struct *sksec_other = other->sk_security;
4563 struct sk_security_struct *sksec_new = newsk->sk_security;
4564 struct common_audit_data ad;
4565 struct lsm_network_audit net = {0,};
4566 int err;
4567
4568 ad.type = LSM_AUDIT_DATA_NET;
4569 ad.u.net = &net;
4570 ad.u.net->sk = other;
4571
4572 err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4573 sksec_other->sclass,
4574 UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4575 if (err)
4576 return err;
4577
4578 /* server child socket */
4579 sksec_new->peer_sid = sksec_sock->sid;
4580 err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4581 &sksec_new->sid);
4582 if (err)
4583 return err;
4584
4585 /* connecting socket */
4586 sksec_sock->peer_sid = sksec_new->sid;
4587
4588 return 0;
4589}
4590
4591static int selinux_socket_unix_may_send(struct socket *sock,
4592 struct socket *other)
4593{
4594 struct sk_security_struct *ssec = sock->sk->sk_security;
4595 struct sk_security_struct *osec = other->sk->sk_security;
4596 struct common_audit_data ad;
4597 struct lsm_network_audit net = {0,};
4598
4599 ad.type = LSM_AUDIT_DATA_NET;
4600 ad.u.net = &net;
4601 ad.u.net->sk = other->sk;
4602
4603 return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4604 &ad);
4605}
4606
4607static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4608 char *addrp, u16 family, u32 peer_sid,
4609 struct common_audit_data *ad)
4610{
4611 int err;
4612 u32 if_sid;
4613 u32 node_sid;
4614
4615 err = sel_netif_sid(ns, ifindex, &if_sid);
4616 if (err)
4617 return err;
4618 err = avc_has_perm(peer_sid, if_sid,
4619 SECCLASS_NETIF, NETIF__INGRESS, ad);
4620 if (err)
4621 return err;
4622
4623 err = sel_netnode_sid(addrp, family, &node_sid);
4624 if (err)
4625 return err;
4626 return avc_has_perm(peer_sid, node_sid,
4627 SECCLASS_NODE, NODE__RECVFROM, ad);
4628}
4629
4630static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4631 u16 family)
4632{
4633 int err = 0;
4634 struct sk_security_struct *sksec = sk->sk_security;
4635 u32 sk_sid = sksec->sid;
4636 struct common_audit_data ad;
4637 struct lsm_network_audit net = {0,};
4638 char *addrp;
4639
4640 ad.type = LSM_AUDIT_DATA_NET;
4641 ad.u.net = &net;
4642 ad.u.net->netif = skb->skb_iif;
4643 ad.u.net->family = family;
4644 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4645 if (err)
4646 return err;
4647
4648 if (selinux_secmark_enabled()) {
4649 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4650 PACKET__RECV, &ad);
4651 if (err)
4652 return err;
4653 }
4654
4655 err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4656 if (err)
4657 return err;
4658 err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4659
4660 return err;
4661}
4662
4663static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4664{
4665 int err;
4666 struct sk_security_struct *sksec = sk->sk_security;
4667 u16 family = sk->sk_family;
4668 u32 sk_sid = sksec->sid;
4669 struct common_audit_data ad;
4670 struct lsm_network_audit net = {0,};
4671 char *addrp;
4672 u8 secmark_active;
4673 u8 peerlbl_active;
4674
4675 if (family != PF_INET && family != PF_INET6)
4676 return 0;
4677
4678 /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4679 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4680 family = PF_INET;
4681
4682 /* If any sort of compatibility mode is enabled then handoff processing
4683 * to the selinux_sock_rcv_skb_compat() function to deal with the
4684 * special handling. We do this in an attempt to keep this function
4685 * as fast and as clean as possible. */
4686 if (!selinux_policycap_netpeer)
4687 return selinux_sock_rcv_skb_compat(sk, skb, family);
4688
4689 secmark_active = selinux_secmark_enabled();
4690 peerlbl_active = selinux_peerlbl_enabled();
4691 if (!secmark_active && !peerlbl_active)
4692 return 0;
4693
4694 ad.type = LSM_AUDIT_DATA_NET;
4695 ad.u.net = &net;
4696 ad.u.net->netif = skb->skb_iif;
4697 ad.u.net->family = family;
4698 err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4699 if (err)
4700 return err;
4701
4702 if (peerlbl_active) {
4703 u32 peer_sid;
4704
4705 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4706 if (err)
4707 return err;
4708 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4709 addrp, family, peer_sid, &ad);
4710 if (err) {
4711 selinux_netlbl_err(skb, family, err, 0);
4712 return err;
4713 }
4714 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4715 PEER__RECV, &ad);
4716 if (err) {
4717 selinux_netlbl_err(skb, family, err, 0);
4718 return err;
4719 }
4720 }
4721
4722 if (secmark_active) {
4723 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4724 PACKET__RECV, &ad);
4725 if (err)
4726 return err;
4727 }
4728
4729 return err;
4730}
4731
4732static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4733 int __user *optlen, unsigned len)
4734{
4735 int err = 0;
4736 char *scontext;
4737 u32 scontext_len;
4738 struct sk_security_struct *sksec = sock->sk->sk_security;
4739 u32 peer_sid = SECSID_NULL;
4740
4741 if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4742 sksec->sclass == SECCLASS_TCP_SOCKET)
4743 peer_sid = sksec->peer_sid;
4744 if (peer_sid == SECSID_NULL)
4745 return -ENOPROTOOPT;
4746
4747 err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4748 if (err)
4749 return err;
4750
4751 if (scontext_len > len) {
4752 err = -ERANGE;
4753 goto out_len;
4754 }
4755
4756 if (copy_to_user(optval, scontext, scontext_len))
4757 err = -EFAULT;
4758
4759out_len:
4760 if (put_user(scontext_len, optlen))
4761 err = -EFAULT;
4762 kfree(scontext);
4763 return err;
4764}
4765
4766static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4767{
4768 u32 peer_secid = SECSID_NULL;
4769 u16 family;
4770 struct inode_security_struct *isec;
4771
4772 if (skb && skb->protocol == htons(ETH_P_IP))
4773 family = PF_INET;
4774 else if (skb && skb->protocol == htons(ETH_P_IPV6))
4775 family = PF_INET6;
4776 else if (sock)
4777 family = sock->sk->sk_family;
4778 else
4779 goto out;
4780
4781 if (sock && family == PF_UNIX) {
4782 isec = inode_security_novalidate(SOCK_INODE(sock));
4783 peer_secid = isec->sid;
4784 } else if (skb)
4785 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4786
4787out:
4788 *secid = peer_secid;
4789 if (peer_secid == SECSID_NULL)
4790 return -EINVAL;
4791 return 0;
4792}
4793
4794static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4795{
4796 struct sk_security_struct *sksec;
4797
4798 sksec = kzalloc(sizeof(*sksec), priority);
4799 if (!sksec)
4800 return -ENOMEM;
4801
4802 sksec->peer_sid = SECINITSID_UNLABELED;
4803 sksec->sid = SECINITSID_UNLABELED;
4804 sksec->sclass = SECCLASS_SOCKET;
4805 selinux_netlbl_sk_security_reset(sksec);
4806 sk->sk_security = sksec;
4807
4808 return 0;
4809}
4810
4811static void selinux_sk_free_security(struct sock *sk)
4812{
4813 struct sk_security_struct *sksec = sk->sk_security;
4814
4815 sk->sk_security = NULL;
4816 selinux_netlbl_sk_security_free(sksec);
4817 kfree(sksec);
4818}
4819
4820static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4821{
4822 struct sk_security_struct *sksec = sk->sk_security;
4823 struct sk_security_struct *newsksec = newsk->sk_security;
4824
4825 newsksec->sid = sksec->sid;
4826 newsksec->peer_sid = sksec->peer_sid;
4827 newsksec->sclass = sksec->sclass;
4828
4829 selinux_netlbl_sk_security_reset(newsksec);
4830}
4831
4832static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4833{
4834 if (!sk)
4835 *secid = SECINITSID_ANY_SOCKET;
4836 else {
4837 struct sk_security_struct *sksec = sk->sk_security;
4838
4839 *secid = sksec->sid;
4840 }
4841}
4842
4843static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4844{
4845 struct inode_security_struct *isec =
4846 inode_security_novalidate(SOCK_INODE(parent));
4847 struct sk_security_struct *sksec = sk->sk_security;
4848
4849 if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4850 sk->sk_family == PF_UNIX)
4851 isec->sid = sksec->sid;
4852 sksec->sclass = isec->sclass;
4853}
4854
4855static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4856 struct request_sock *req)
4857{
4858 struct sk_security_struct *sksec = sk->sk_security;
4859 int err;
4860 u16 family = req->rsk_ops->family;
4861 u32 connsid;
4862 u32 peersid;
4863
4864 err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4865 if (err)
4866 return err;
4867 err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4868 if (err)
4869 return err;
4870 req->secid = connsid;
4871 req->peer_secid = peersid;
4872
4873 return selinux_netlbl_inet_conn_request(req, family);
4874}
4875
4876static void selinux_inet_csk_clone(struct sock *newsk,
4877 const struct request_sock *req)
4878{
4879 struct sk_security_struct *newsksec = newsk->sk_security;
4880
4881 newsksec->sid = req->secid;
4882 newsksec->peer_sid = req->peer_secid;
4883 /* NOTE: Ideally, we should also get the isec->sid for the
4884 new socket in sync, but we don't have the isec available yet.
4885 So we will wait until sock_graft to do it, by which
4886 time it will have been created and available. */
4887
4888 /* We don't need to take any sort of lock here as we are the only
4889 * thread with access to newsksec */
4890 selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4891}
4892
4893static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4894{
4895 u16 family = sk->sk_family;
4896 struct sk_security_struct *sksec = sk->sk_security;
4897
4898 /* handle mapped IPv4 packets arriving via IPv6 sockets */
4899 if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4900 family = PF_INET;
4901
4902 selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4903}
4904
4905static int selinux_secmark_relabel_packet(u32 sid)
4906{
4907 const struct task_security_struct *__tsec;
4908 u32 tsid;
4909
4910 __tsec = current_security();
4911 tsid = __tsec->sid;
4912
4913 return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4914}
4915
4916static void selinux_secmark_refcount_inc(void)
4917{
4918 atomic_inc(&selinux_secmark_refcount);
4919}
4920
4921static void selinux_secmark_refcount_dec(void)
4922{
4923 atomic_dec(&selinux_secmark_refcount);
4924}
4925
4926static void selinux_req_classify_flow(const struct request_sock *req,
4927 struct flowi *fl)
4928{
4929 fl->flowi_secid = req->secid;
4930}
4931
4932static int selinux_tun_dev_alloc_security(void **security)
4933{
4934 struct tun_security_struct *tunsec;
4935
4936 tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4937 if (!tunsec)
4938 return -ENOMEM;
4939 tunsec->sid = current_sid();
4940
4941 *security = tunsec;
4942 return 0;
4943}
4944
4945static void selinux_tun_dev_free_security(void *security)
4946{
4947 kfree(security);
4948}
4949
4950static int selinux_tun_dev_create(void)
4951{
4952 u32 sid = current_sid();
4953
4954 /* we aren't taking into account the "sockcreate" SID since the socket
4955 * that is being created here is not a socket in the traditional sense,
4956 * instead it is a private sock, accessible only to the kernel, and
4957 * representing a wide range of network traffic spanning multiple
4958 * connections unlike traditional sockets - check the TUN driver to
4959 * get a better understanding of why this socket is special */
4960
4961 return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4962 NULL);
4963}
4964
4965static int selinux_tun_dev_attach_queue(void *security)
4966{
4967 struct tun_security_struct *tunsec = security;
4968
4969 return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4970 TUN_SOCKET__ATTACH_QUEUE, NULL);
4971}
4972
4973static int selinux_tun_dev_attach(struct sock *sk, void *security)
4974{
4975 struct tun_security_struct *tunsec = security;
4976 struct sk_security_struct *sksec = sk->sk_security;
4977
4978 /* we don't currently perform any NetLabel based labeling here and it
4979 * isn't clear that we would want to do so anyway; while we could apply
4980 * labeling without the support of the TUN user the resulting labeled
4981 * traffic from the other end of the connection would almost certainly
4982 * cause confusion to the TUN user that had no idea network labeling
4983 * protocols were being used */
4984
4985 sksec->sid = tunsec->sid;
4986 sksec->sclass = SECCLASS_TUN_SOCKET;
4987
4988 return 0;
4989}
4990
4991static int selinux_tun_dev_open(void *security)
4992{
4993 struct tun_security_struct *tunsec = security;
4994 u32 sid = current_sid();
4995 int err;
4996
4997 err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4998 TUN_SOCKET__RELABELFROM, NULL);
4999 if (err)
5000 return err;
5001 err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5002 TUN_SOCKET__RELABELTO, NULL);
5003 if (err)
5004 return err;
5005 tunsec->sid = sid;
5006
5007 return 0;
5008}
5009
5010static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5011{
5012 int err = 0;
5013 u32 perm;
5014 struct nlmsghdr *nlh;
5015 struct sk_security_struct *sksec = sk->sk_security;
5016
5017 if (skb->len < NLMSG_HDRLEN) {
5018 err = -EINVAL;
5019 goto out;
5020 }
5021 nlh = nlmsg_hdr(skb);
5022
5023 err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5024 if (err) {
5025 if (err == -EINVAL) {
5026 pr_warn_ratelimited("SELinux: unrecognized netlink"
5027 " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5028 " pig=%d comm=%s\n",
5029 sk->sk_protocol, nlh->nlmsg_type,
5030 secclass_map[sksec->sclass - 1].name,
5031 task_pid_nr(current), current->comm);
5032 if (!selinux_enforcing || security_get_allow_unknown())
5033 err = 0;
5034 }
5035
5036 /* Ignore */
5037 if (err == -ENOENT)
5038 err = 0;
5039 goto out;
5040 }
5041
5042 err = sock_has_perm(current, sk, perm);
5043out:
5044 return err;
5045}
5046
5047#ifdef CONFIG_NETFILTER
5048
5049static unsigned int selinux_ip_forward(struct sk_buff *skb,
5050 const struct net_device *indev,
5051 u16 family)
5052{
5053 int err;
5054 char *addrp;
5055 u32 peer_sid;
5056 struct common_audit_data ad;
5057 struct lsm_network_audit net = {0,};
5058 u8 secmark_active;
5059 u8 netlbl_active;
5060 u8 peerlbl_active;
5061
5062 if (!selinux_policycap_netpeer)
5063 return NF_ACCEPT;
5064
5065 secmark_active = selinux_secmark_enabled();
5066 netlbl_active = netlbl_enabled();
5067 peerlbl_active = selinux_peerlbl_enabled();
5068 if (!secmark_active && !peerlbl_active)
5069 return NF_ACCEPT;
5070
5071 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5072 return NF_DROP;
5073
5074 ad.type = LSM_AUDIT_DATA_NET;
5075 ad.u.net = &net;
5076 ad.u.net->netif = indev->ifindex;
5077 ad.u.net->family = family;
5078 if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5079 return NF_DROP;
5080
5081 if (peerlbl_active) {
5082 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5083 addrp, family, peer_sid, &ad);
5084 if (err) {
5085 selinux_netlbl_err(skb, family, err, 1);
5086 return NF_DROP;
5087 }
5088 }
5089
5090 if (secmark_active)
5091 if (avc_has_perm(peer_sid, skb->secmark,
5092 SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5093 return NF_DROP;
5094
5095 if (netlbl_active)
5096 /* we do this in the FORWARD path and not the POST_ROUTING
5097 * path because we want to make sure we apply the necessary
5098 * labeling before IPsec is applied so we can leverage AH
5099 * protection */
5100 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5101 return NF_DROP;
5102
5103 return NF_ACCEPT;
5104}
5105
5106static unsigned int selinux_ipv4_forward(void *priv,
5107 struct sk_buff *skb,
5108 const struct nf_hook_state *state)
5109{
5110 return selinux_ip_forward(skb, state->in, PF_INET);
5111}
5112
5113#if IS_ENABLED(CONFIG_IPV6)
5114static unsigned int selinux_ipv6_forward(void *priv,
5115 struct sk_buff *skb,
5116 const struct nf_hook_state *state)
5117{
5118 return selinux_ip_forward(skb, state->in, PF_INET6);
5119}
5120#endif /* IPV6 */
5121
5122static unsigned int selinux_ip_output(struct sk_buff *skb,
5123 u16 family)
5124{
5125 struct sock *sk;
5126 u32 sid;
5127
5128 if (!netlbl_enabled())
5129 return NF_ACCEPT;
5130
5131 /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5132 * because we want to make sure we apply the necessary labeling
5133 * before IPsec is applied so we can leverage AH protection */
5134 sk = skb->sk;
5135 if (sk) {
5136 struct sk_security_struct *sksec;
5137
5138 if (sk_listener(sk))
5139 /* if the socket is the listening state then this
5140 * packet is a SYN-ACK packet which means it needs to
5141 * be labeled based on the connection/request_sock and
5142 * not the parent socket. unfortunately, we can't
5143 * lookup the request_sock yet as it isn't queued on
5144 * the parent socket until after the SYN-ACK is sent.
5145 * the "solution" is to simply pass the packet as-is
5146 * as any IP option based labeling should be copied
5147 * from the initial connection request (in the IP
5148 * layer). it is far from ideal, but until we get a
5149 * security label in the packet itself this is the
5150 * best we can do. */
5151 return NF_ACCEPT;
5152
5153 /* standard practice, label using the parent socket */
5154 sksec = sk->sk_security;
5155 sid = sksec->sid;
5156 } else
5157 sid = SECINITSID_KERNEL;
5158 if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5159 return NF_DROP;
5160
5161 return NF_ACCEPT;
5162}
5163
5164static unsigned int selinux_ipv4_output(void *priv,
5165 struct sk_buff *skb,
5166 const struct nf_hook_state *state)
5167{
5168 return selinux_ip_output(skb, PF_INET);
5169}
5170
5171#if IS_ENABLED(CONFIG_IPV6)
5172static unsigned int selinux_ipv6_output(void *priv,
5173 struct sk_buff *skb,
5174 const struct nf_hook_state *state)
5175{
5176 return selinux_ip_output(skb, PF_INET6);
5177}
5178#endif /* IPV6 */
5179
5180static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5181 int ifindex,
5182 u16 family)
5183{
5184 struct sock *sk = skb_to_full_sk(skb);
5185 struct sk_security_struct *sksec;
5186 struct common_audit_data ad;
5187 struct lsm_network_audit net = {0,};
5188 char *addrp;
5189 u8 proto;
5190
5191 if (sk == NULL)
5192 return NF_ACCEPT;
5193 sksec = sk->sk_security;
5194
5195 ad.type = LSM_AUDIT_DATA_NET;
5196 ad.u.net = &net;
5197 ad.u.net->netif = ifindex;
5198 ad.u.net->family = family;
5199 if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5200 return NF_DROP;
5201
5202 if (selinux_secmark_enabled())
5203 if (avc_has_perm(sksec->sid, skb->secmark,
5204 SECCLASS_PACKET, PACKET__SEND, &ad))
5205 return NF_DROP_ERR(-ECONNREFUSED);
5206
5207 if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5208 return NF_DROP_ERR(-ECONNREFUSED);
5209
5210 return NF_ACCEPT;
5211}
5212
5213static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5214 const struct net_device *outdev,
5215 u16 family)
5216{
5217 u32 secmark_perm;
5218 u32 peer_sid;
5219 int ifindex = outdev->ifindex;
5220 struct sock *sk;
5221 struct common_audit_data ad;
5222 struct lsm_network_audit net = {0,};
5223 char *addrp;
5224 u8 secmark_active;
5225 u8 peerlbl_active;
5226
5227 /* If any sort of compatibility mode is enabled then handoff processing
5228 * to the selinux_ip_postroute_compat() function to deal with the
5229 * special handling. We do this in an attempt to keep this function
5230 * as fast and as clean as possible. */
5231 if (!selinux_policycap_netpeer)
5232 return selinux_ip_postroute_compat(skb, ifindex, family);
5233
5234 secmark_active = selinux_secmark_enabled();
5235 peerlbl_active = selinux_peerlbl_enabled();
5236 if (!secmark_active && !peerlbl_active)
5237 return NF_ACCEPT;
5238
5239 sk = skb_to_full_sk(skb);
5240
5241#ifdef CONFIG_XFRM
5242 /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5243 * packet transformation so allow the packet to pass without any checks
5244 * since we'll have another chance to perform access control checks
5245 * when the packet is on it's final way out.
5246 * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5247 * is NULL, in this case go ahead and apply access control.
5248 * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5249 * TCP listening state we cannot wait until the XFRM processing
5250 * is done as we will miss out on the SA label if we do;
5251 * unfortunately, this means more work, but it is only once per
5252 * connection. */
5253 if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5254 !(sk && sk_listener(sk)))
5255 return NF_ACCEPT;
5256#endif
5257
5258 if (sk == NULL) {
5259 /* Without an associated socket the packet is either coming
5260 * from the kernel or it is being forwarded; check the packet
5261 * to determine which and if the packet is being forwarded
5262 * query the packet directly to determine the security label. */
5263 if (skb->skb_iif) {
5264 secmark_perm = PACKET__FORWARD_OUT;
5265 if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5266 return NF_DROP;
5267 } else {
5268 secmark_perm = PACKET__SEND;
5269 peer_sid = SECINITSID_KERNEL;
5270 }
5271 } else if (sk_listener(sk)) {
5272 /* Locally generated packet but the associated socket is in the
5273 * listening state which means this is a SYN-ACK packet. In
5274 * this particular case the correct security label is assigned
5275 * to the connection/request_sock but unfortunately we can't
5276 * query the request_sock as it isn't queued on the parent
5277 * socket until after the SYN-ACK packet is sent; the only
5278 * viable choice is to regenerate the label like we do in
5279 * selinux_inet_conn_request(). See also selinux_ip_output()
5280 * for similar problems. */
5281 u32 skb_sid;
5282 struct sk_security_struct *sksec;
5283
5284 sksec = sk->sk_security;
5285 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5286 return NF_DROP;
5287 /* At this point, if the returned skb peerlbl is SECSID_NULL
5288 * and the packet has been through at least one XFRM
5289 * transformation then we must be dealing with the "final"
5290 * form of labeled IPsec packet; since we've already applied
5291 * all of our access controls on this packet we can safely
5292 * pass the packet. */
5293 if (skb_sid == SECSID_NULL) {
5294 switch (family) {
5295 case PF_INET:
5296 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5297 return NF_ACCEPT;
5298 break;
5299 case PF_INET6:
5300 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5301 return NF_ACCEPT;
5302 break;
5303 default:
5304 return NF_DROP_ERR(-ECONNREFUSED);
5305 }
5306 }
5307 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5308 return NF_DROP;
5309 secmark_perm = PACKET__SEND;
5310 } else {
5311 /* Locally generated packet, fetch the security label from the
5312 * associated socket. */
5313 struct sk_security_struct *sksec = sk->sk_security;
5314 peer_sid = sksec->sid;
5315 secmark_perm = PACKET__SEND;
5316 }
5317
5318 ad.type = LSM_AUDIT_DATA_NET;
5319 ad.u.net = &net;
5320 ad.u.net->netif = ifindex;
5321 ad.u.net->family = family;
5322 if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5323 return NF_DROP;
5324
5325 if (secmark_active)
5326 if (avc_has_perm(peer_sid, skb->secmark,
5327 SECCLASS_PACKET, secmark_perm, &ad))
5328 return NF_DROP_ERR(-ECONNREFUSED);
5329
5330 if (peerlbl_active) {
5331 u32 if_sid;
5332 u32 node_sid;
5333
5334 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5335 return NF_DROP;
5336 if (avc_has_perm(peer_sid, if_sid,
5337 SECCLASS_NETIF, NETIF__EGRESS, &ad))
5338 return NF_DROP_ERR(-ECONNREFUSED);
5339
5340 if (sel_netnode_sid(addrp, family, &node_sid))
5341 return NF_DROP;
5342 if (avc_has_perm(peer_sid, node_sid,
5343 SECCLASS_NODE, NODE__SENDTO, &ad))
5344 return NF_DROP_ERR(-ECONNREFUSED);
5345 }
5346
5347 return NF_ACCEPT;
5348}
5349
5350static unsigned int selinux_ipv4_postroute(void *priv,
5351 struct sk_buff *skb,
5352 const struct nf_hook_state *state)
5353{
5354 return selinux_ip_postroute(skb, state->out, PF_INET);
5355}
5356
5357#if IS_ENABLED(CONFIG_IPV6)
5358static unsigned int selinux_ipv6_postroute(void *priv,
5359 struct sk_buff *skb,
5360 const struct nf_hook_state *state)
5361{
5362 return selinux_ip_postroute(skb, state->out, PF_INET6);
5363}
5364#endif /* IPV6 */
5365
5366#endif /* CONFIG_NETFILTER */
5367
5368static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5369{
5370 return selinux_nlmsg_perm(sk, skb);
5371}
5372
5373static int ipc_alloc_security(struct task_struct *task,
5374 struct kern_ipc_perm *perm,
5375 u16 sclass)
5376{
5377 struct ipc_security_struct *isec;
5378 u32 sid;
5379
5380 isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5381 if (!isec)
5382 return -ENOMEM;
5383
5384 sid = task_sid(task);
5385 isec->sclass = sclass;
5386 isec->sid = sid;
5387 perm->security = isec;
5388
5389 return 0;
5390}
5391
5392static void ipc_free_security(struct kern_ipc_perm *perm)
5393{
5394 struct ipc_security_struct *isec = perm->security;
5395 perm->security = NULL;
5396 kfree(isec);
5397}
5398
5399static int msg_msg_alloc_security(struct msg_msg *msg)
5400{
5401 struct msg_security_struct *msec;
5402
5403 msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5404 if (!msec)
5405 return -ENOMEM;
5406
5407 msec->sid = SECINITSID_UNLABELED;
5408 msg->security = msec;
5409
5410 return 0;
5411}
5412
5413static void msg_msg_free_security(struct msg_msg *msg)
5414{
5415 struct msg_security_struct *msec = msg->security;
5416
5417 msg->security = NULL;
5418 kfree(msec);
5419}
5420
5421static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5422 u32 perms)
5423{
5424 struct ipc_security_struct *isec;
5425 struct common_audit_data ad;
5426 u32 sid = current_sid();
5427
5428 isec = ipc_perms->security;
5429
5430 ad.type = LSM_AUDIT_DATA_IPC;
5431 ad.u.ipc_id = ipc_perms->key;
5432
5433 return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5434}
5435
5436static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5437{
5438 return msg_msg_alloc_security(msg);
5439}
5440
5441static void selinux_msg_msg_free_security(struct msg_msg *msg)
5442{
5443 msg_msg_free_security(msg);
5444}
5445
5446/* message queue security operations */
5447static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5448{
5449 struct ipc_security_struct *isec;
5450 struct common_audit_data ad;
5451 u32 sid = current_sid();
5452 int rc;
5453
5454 rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5455 if (rc)
5456 return rc;
5457
5458 isec = msq->q_perm.security;
5459
5460 ad.type = LSM_AUDIT_DATA_IPC;
5461 ad.u.ipc_id = msq->q_perm.key;
5462
5463 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5464 MSGQ__CREATE, &ad);
5465 if (rc) {
5466 ipc_free_security(&msq->q_perm);
5467 return rc;
5468 }
5469 return 0;
5470}
5471
5472static void selinux_msg_queue_free_security(struct msg_queue *msq)
5473{
5474 ipc_free_security(&msq->q_perm);
5475}
5476
5477static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5478{
5479 struct ipc_security_struct *isec;
5480 struct common_audit_data ad;
5481 u32 sid = current_sid();
5482
5483 isec = msq->q_perm.security;
5484
5485 ad.type = LSM_AUDIT_DATA_IPC;
5486 ad.u.ipc_id = msq->q_perm.key;
5487
5488 return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5489 MSGQ__ASSOCIATE, &ad);
5490}
5491
5492static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5493{
5494 int err;
5495 int perms;
5496
5497 switch (cmd) {
5498 case IPC_INFO:
5499 case MSG_INFO:
5500 /* No specific object, just general system-wide information. */
5501 return task_has_system(current, SYSTEM__IPC_INFO);
5502 case IPC_STAT:
5503 case MSG_STAT:
5504 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5505 break;
5506 case IPC_SET:
5507 perms = MSGQ__SETATTR;
5508 break;
5509 case IPC_RMID:
5510 perms = MSGQ__DESTROY;
5511 break;
5512 default:
5513 return 0;
5514 }
5515
5516 err = ipc_has_perm(&msq->q_perm, perms);
5517 return err;
5518}
5519
5520static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5521{
5522 struct ipc_security_struct *isec;
5523 struct msg_security_struct *msec;
5524 struct common_audit_data ad;
5525 u32 sid = current_sid();
5526 int rc;
5527
5528 isec = msq->q_perm.security;
5529 msec = msg->security;
5530
5531 /*
5532 * First time through, need to assign label to the message
5533 */
5534 if (msec->sid == SECINITSID_UNLABELED) {
5535 /*
5536 * Compute new sid based on current process and
5537 * message queue this message will be stored in
5538 */
5539 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5540 NULL, &msec->sid);
5541 if (rc)
5542 return rc;
5543 }
5544
5545 ad.type = LSM_AUDIT_DATA_IPC;
5546 ad.u.ipc_id = msq->q_perm.key;
5547
5548 /* Can this process write to the queue? */
5549 rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5550 MSGQ__WRITE, &ad);
5551 if (!rc)
5552 /* Can this process send the message */
5553 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5554 MSG__SEND, &ad);
5555 if (!rc)
5556 /* Can the message be put in the queue? */
5557 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5558 MSGQ__ENQUEUE, &ad);
5559
5560 return rc;
5561}
5562
5563static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5564 struct task_struct *target,
5565 long type, int mode)
5566{
5567 struct ipc_security_struct *isec;
5568 struct msg_security_struct *msec;
5569 struct common_audit_data ad;
5570 u32 sid = task_sid(target);
5571 int rc;
5572
5573 isec = msq->q_perm.security;
5574 msec = msg->security;
5575
5576 ad.type = LSM_AUDIT_DATA_IPC;
5577 ad.u.ipc_id = msq->q_perm.key;
5578
5579 rc = avc_has_perm(sid, isec->sid,
5580 SECCLASS_MSGQ, MSGQ__READ, &ad);
5581 if (!rc)
5582 rc = avc_has_perm(sid, msec->sid,
5583 SECCLASS_MSG, MSG__RECEIVE, &ad);
5584 return rc;
5585}
5586
5587/* Shared Memory security operations */
5588static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5589{
5590 struct ipc_security_struct *isec;
5591 struct common_audit_data ad;
5592 u32 sid = current_sid();
5593 int rc;
5594
5595 rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5596 if (rc)
5597 return rc;
5598
5599 isec = shp->shm_perm.security;
5600
5601 ad.type = LSM_AUDIT_DATA_IPC;
5602 ad.u.ipc_id = shp->shm_perm.key;
5603
5604 rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5605 SHM__CREATE, &ad);
5606 if (rc) {
5607 ipc_free_security(&shp->shm_perm);
5608 return rc;
5609 }
5610 return 0;
5611}
5612
5613static void selinux_shm_free_security(struct shmid_kernel *shp)
5614{
5615 ipc_free_security(&shp->shm_perm);
5616}
5617
5618static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5619{
5620 struct ipc_security_struct *isec;
5621 struct common_audit_data ad;
5622 u32 sid = current_sid();
5623
5624 isec = shp->shm_perm.security;
5625
5626 ad.type = LSM_AUDIT_DATA_IPC;
5627 ad.u.ipc_id = shp->shm_perm.key;
5628
5629 return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5630 SHM__ASSOCIATE, &ad);
5631}
5632
5633/* Note, at this point, shp is locked down */
5634static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5635{
5636 int perms;
5637 int err;
5638
5639 switch (cmd) {
5640 case IPC_INFO:
5641 case SHM_INFO:
5642 /* No specific object, just general system-wide information. */
5643 return task_has_system(current, SYSTEM__IPC_INFO);
5644 case IPC_STAT:
5645 case SHM_STAT:
5646 perms = SHM__GETATTR | SHM__ASSOCIATE;
5647 break;
5648 case IPC_SET:
5649 perms = SHM__SETATTR;
5650 break;
5651 case SHM_LOCK:
5652 case SHM_UNLOCK:
5653 perms = SHM__LOCK;
5654 break;
5655 case IPC_RMID:
5656 perms = SHM__DESTROY;
5657 break;
5658 default:
5659 return 0;
5660 }
5661
5662 err = ipc_has_perm(&shp->shm_perm, perms);
5663 return err;
5664}
5665
5666static int selinux_shm_shmat(struct shmid_kernel *shp,
5667 char __user *shmaddr, int shmflg)
5668{
5669 u32 perms;
5670
5671 if (shmflg & SHM_RDONLY)
5672 perms = SHM__READ;
5673 else
5674 perms = SHM__READ | SHM__WRITE;
5675
5676 return ipc_has_perm(&shp->shm_perm, perms);
5677}
5678
5679/* Semaphore security operations */
5680static int selinux_sem_alloc_security(struct sem_array *sma)
5681{
5682 struct ipc_security_struct *isec;
5683 struct common_audit_data ad;
5684 u32 sid = current_sid();
5685 int rc;
5686
5687 rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5688 if (rc)
5689 return rc;
5690
5691 isec = sma->sem_perm.security;
5692
5693 ad.type = LSM_AUDIT_DATA_IPC;
5694 ad.u.ipc_id = sma->sem_perm.key;
5695
5696 rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5697 SEM__CREATE, &ad);
5698 if (rc) {
5699 ipc_free_security(&sma->sem_perm);
5700 return rc;
5701 }
5702 return 0;
5703}
5704
5705static void selinux_sem_free_security(struct sem_array *sma)
5706{
5707 ipc_free_security(&sma->sem_perm);
5708}
5709
5710static int selinux_sem_associate(struct sem_array *sma, int semflg)
5711{
5712 struct ipc_security_struct *isec;
5713 struct common_audit_data ad;
5714 u32 sid = current_sid();
5715
5716 isec = sma->sem_perm.security;
5717
5718 ad.type = LSM_AUDIT_DATA_IPC;
5719 ad.u.ipc_id = sma->sem_perm.key;
5720
5721 return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5722 SEM__ASSOCIATE, &ad);
5723}
5724
5725/* Note, at this point, sma is locked down */
5726static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5727{
5728 int err;
5729 u32 perms;
5730
5731 switch (cmd) {
5732 case IPC_INFO:
5733 case SEM_INFO:
5734 /* No specific object, just general system-wide information. */
5735 return task_has_system(current, SYSTEM__IPC_INFO);
5736 case GETPID:
5737 case GETNCNT:
5738 case GETZCNT:
5739 perms = SEM__GETATTR;
5740 break;
5741 case GETVAL:
5742 case GETALL:
5743 perms = SEM__READ;
5744 break;
5745 case SETVAL:
5746 case SETALL:
5747 perms = SEM__WRITE;
5748 break;
5749 case IPC_RMID:
5750 perms = SEM__DESTROY;
5751 break;
5752 case IPC_SET:
5753 perms = SEM__SETATTR;
5754 break;
5755 case IPC_STAT:
5756 case SEM_STAT:
5757 perms = SEM__GETATTR | SEM__ASSOCIATE;
5758 break;
5759 default:
5760 return 0;
5761 }
5762
5763 err = ipc_has_perm(&sma->sem_perm, perms);
5764 return err;
5765}
5766
5767static int selinux_sem_semop(struct sem_array *sma,
5768 struct sembuf *sops, unsigned nsops, int alter)
5769{
5770 u32 perms;
5771
5772 if (alter)
5773 perms = SEM__READ | SEM__WRITE;
5774 else
5775 perms = SEM__READ;
5776
5777 return ipc_has_perm(&sma->sem_perm, perms);
5778}
5779
5780static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5781{
5782 u32 av = 0;
5783
5784 av = 0;
5785 if (flag & S_IRUGO)
5786 av |= IPC__UNIX_READ;
5787 if (flag & S_IWUGO)
5788 av |= IPC__UNIX_WRITE;
5789
5790 if (av == 0)
5791 return 0;
5792
5793 return ipc_has_perm(ipcp, av);
5794}
5795
5796static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5797{
5798 struct ipc_security_struct *isec = ipcp->security;
5799 *secid = isec->sid;
5800}
5801
5802static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5803{
5804 if (inode)
5805 inode_doinit_with_dentry(inode, dentry);
5806}
5807
5808static int selinux_getprocattr(struct task_struct *p,
5809 char *name, char **value)
5810{
5811 const struct task_security_struct *__tsec;
5812 u32 sid;
5813 int error;
5814 unsigned len;
5815
5816 if (current != p) {
5817 error = current_has_perm(p, PROCESS__GETATTR);
5818 if (error)
5819 return error;
5820 }
5821
5822 rcu_read_lock();
5823 __tsec = __task_cred(p)->security;
5824
5825 if (!strcmp(name, "current"))
5826 sid = __tsec->sid;
5827 else if (!strcmp(name, "prev"))
5828 sid = __tsec->osid;
5829 else if (!strcmp(name, "exec"))
5830 sid = __tsec->exec_sid;
5831 else if (!strcmp(name, "fscreate"))
5832 sid = __tsec->create_sid;
5833 else if (!strcmp(name, "keycreate"))
5834 sid = __tsec->keycreate_sid;
5835 else if (!strcmp(name, "sockcreate"))
5836 sid = __tsec->sockcreate_sid;
5837 else
5838 goto invalid;
5839 rcu_read_unlock();
5840
5841 if (!sid)
5842 return 0;
5843
5844 error = security_sid_to_context(sid, value, &len);
5845 if (error)
5846 return error;
5847 return len;
5848
5849invalid:
5850 rcu_read_unlock();
5851 return -EINVAL;
5852}
5853
5854static int selinux_setprocattr(struct task_struct *p,
5855 char *name, void *value, size_t size)
5856{
5857 struct task_security_struct *tsec;
5858 struct cred *new;
5859 u32 sid = 0, ptsid;
5860 int error;
5861 char *str = value;
5862
5863 if (current != p) {
5864 /* SELinux only allows a process to change its own
5865 security attributes. */
5866 return -EACCES;
5867 }
5868
5869 /*
5870 * Basic control over ability to set these attributes at all.
5871 * current == p, but we'll pass them separately in case the
5872 * above restriction is ever removed.
5873 */
5874 if (!strcmp(name, "exec"))
5875 error = current_has_perm(p, PROCESS__SETEXEC);
5876 else if (!strcmp(name, "fscreate"))
5877 error = current_has_perm(p, PROCESS__SETFSCREATE);
5878 else if (!strcmp(name, "keycreate"))
5879 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5880 else if (!strcmp(name, "sockcreate"))
5881 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5882 else if (!strcmp(name, "current"))
5883 error = current_has_perm(p, PROCESS__SETCURRENT);
5884 else
5885 error = -EINVAL;
5886 if (error)
5887 return error;
5888
5889 /* Obtain a SID for the context, if one was specified. */
5890 if (size && str[0] && str[0] != '\n') {
5891 if (str[size-1] == '\n') {
5892 str[size-1] = 0;
5893 size--;
5894 }
5895 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5896 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5897 if (!capable(CAP_MAC_ADMIN)) {
5898 struct audit_buffer *ab;
5899 size_t audit_size;
5900
5901 /* We strip a nul only if it is at the end, otherwise the
5902 * context contains a nul and we should audit that */
5903 if (str[size - 1] == '\0')
5904 audit_size = size - 1;
5905 else
5906 audit_size = size;
5907 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5908 audit_log_format(ab, "op=fscreate invalid_context=");
5909 audit_log_n_untrustedstring(ab, value, audit_size);
5910 audit_log_end(ab);
5911
5912 return error;
5913 }
5914 error = security_context_to_sid_force(value, size,
5915 &sid);
5916 }
5917 if (error)
5918 return error;
5919 }
5920
5921 new = prepare_creds();
5922 if (!new)
5923 return -ENOMEM;
5924
5925 /* Permission checking based on the specified context is
5926 performed during the actual operation (execve,
5927 open/mkdir/...), when we know the full context of the
5928 operation. See selinux_bprm_set_creds for the execve
5929 checks and may_create for the file creation checks. The
5930 operation will then fail if the context is not permitted. */
5931 tsec = new->security;
5932 if (!strcmp(name, "exec")) {
5933 tsec->exec_sid = sid;
5934 } else if (!strcmp(name, "fscreate")) {
5935 tsec->create_sid = sid;
5936 } else if (!strcmp(name, "keycreate")) {
5937 error = may_create_key(sid, p);
5938 if (error)
5939 goto abort_change;
5940 tsec->keycreate_sid = sid;
5941 } else if (!strcmp(name, "sockcreate")) {
5942 tsec->sockcreate_sid = sid;
5943 } else if (!strcmp(name, "current")) {
5944 error = -EINVAL;
5945 if (sid == 0)
5946 goto abort_change;
5947
5948 /* Only allow single threaded processes to change context */
5949 error = -EPERM;
5950 if (!current_is_single_threaded()) {
5951 error = security_bounded_transition(tsec->sid, sid);
5952 if (error)
5953 goto abort_change;
5954 }
5955
5956 /* Check permissions for the transition. */
5957 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5958 PROCESS__DYNTRANSITION, NULL);
5959 if (error)
5960 goto abort_change;
5961
5962 /* Check for ptracing, and update the task SID if ok.
5963 Otherwise, leave SID unchanged and fail. */
5964 ptsid = ptrace_parent_sid(p);
5965 if (ptsid != 0) {
5966 error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5967 PROCESS__PTRACE, NULL);
5968 if (error)
5969 goto abort_change;
5970 }
5971
5972 tsec->sid = sid;
5973 } else {
5974 error = -EINVAL;
5975 goto abort_change;
5976 }
5977
5978 commit_creds(new);
5979 return size;
5980
5981abort_change:
5982 abort_creds(new);
5983 return error;
5984}
5985
5986static int selinux_ismaclabel(const char *name)
5987{
5988 return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5989}
5990
5991static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5992{
5993 return security_sid_to_context(secid, secdata, seclen);
5994}
5995
5996static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5997{
5998 return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5999}
6000
6001static void selinux_release_secctx(char *secdata, u32 seclen)
6002{
6003 kfree(secdata);
6004}
6005
6006static void selinux_inode_invalidate_secctx(struct inode *inode)
6007{
6008 struct inode_security_struct *isec = inode->i_security;
6009
6010 spin_lock(&isec->lock);
6011 isec->initialized = LABEL_INVALID;
6012 spin_unlock(&isec->lock);
6013}
6014
6015/*
6016 * called with inode->i_mutex locked
6017 */
6018static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6019{
6020 return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6021}
6022
6023/*
6024 * called with inode->i_mutex locked
6025 */
6026static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6027{
6028 return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6029}
6030
6031static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6032{
6033 int len = 0;
6034 len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6035 ctx, true);
6036 if (len < 0)
6037 return len;
6038 *ctxlen = len;
6039 return 0;
6040}
6041#ifdef CONFIG_KEYS
6042
6043static int selinux_key_alloc(struct key *k, const struct cred *cred,
6044 unsigned long flags)
6045{
6046 const struct task_security_struct *tsec;
6047 struct key_security_struct *ksec;
6048
6049 ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6050 if (!ksec)
6051 return -ENOMEM;
6052
6053 tsec = cred->security;
6054 if (tsec->keycreate_sid)
6055 ksec->sid = tsec->keycreate_sid;
6056 else
6057 ksec->sid = tsec->sid;
6058
6059 k->security = ksec;
6060 return 0;
6061}
6062
6063static void selinux_key_free(struct key *k)
6064{
6065 struct key_security_struct *ksec = k->security;
6066
6067 k->security = NULL;
6068 kfree(ksec);
6069}
6070
6071static int selinux_key_permission(key_ref_t key_ref,
6072 const struct cred *cred,
6073 unsigned perm)
6074{
6075 struct key *key;
6076 struct key_security_struct *ksec;
6077 u32 sid;
6078
6079 /* if no specific permissions are requested, we skip the
6080 permission check. No serious, additional covert channels
6081 appear to be created. */
6082 if (perm == 0)
6083 return 0;
6084
6085 sid = cred_sid(cred);
6086
6087 key = key_ref_to_ptr(key_ref);
6088 ksec = key->security;
6089
6090 return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6091}
6092
6093static int selinux_key_getsecurity(struct key *key, char **_buffer)
6094{
6095 struct key_security_struct *ksec = key->security;
6096 char *context = NULL;
6097 unsigned len;
6098 int rc;
6099
6100 rc = security_sid_to_context(ksec->sid, &context, &len);
6101 if (!rc)
6102 rc = len;
6103 *_buffer = context;
6104 return rc;
6105}
6106
6107#endif
6108
6109static struct security_hook_list selinux_hooks[] = {
6110 LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6111 LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6112 LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6113 LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6114
6115 LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6116 LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6117 LSM_HOOK_INIT(capget, selinux_capget),
6118 LSM_HOOK_INIT(capset, selinux_capset),
6119 LSM_HOOK_INIT(capable, selinux_capable),
6120 LSM_HOOK_INIT(quotactl, selinux_quotactl),
6121 LSM_HOOK_INIT(quota_on, selinux_quota_on),
6122 LSM_HOOK_INIT(syslog, selinux_syslog),
6123 LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6124
6125 LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6126
6127 LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6128 LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6129 LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6130 LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
6131
6132 LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6133 LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6134 LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6135 LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6136 LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6137 LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6138 LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6139 LSM_HOOK_INIT(sb_mount, selinux_mount),
6140 LSM_HOOK_INIT(sb_umount, selinux_umount),
6141 LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6142 LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6143 LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6144
6145 LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6146 LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6147
6148 LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6149 LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6150 LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6151 LSM_HOOK_INIT(inode_create, selinux_inode_create),
6152 LSM_HOOK_INIT(inode_link, selinux_inode_link),
6153 LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6154 LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6155 LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6156 LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6157 LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6158 LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6159 LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6160 LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6161 LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6162 LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6163 LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6164 LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6165 LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6166 LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6167 LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6168 LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6169 LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6170 LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6171 LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6172 LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6173 LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6174 LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6175
6176 LSM_HOOK_INIT(file_permission, selinux_file_permission),
6177 LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6178 LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6179 LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6180 LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6181 LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6182 LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6183 LSM_HOOK_INIT(file_lock, selinux_file_lock),
6184 LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6185 LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6186 LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6187 LSM_HOOK_INIT(file_receive, selinux_file_receive),
6188
6189 LSM_HOOK_INIT(file_open, selinux_file_open),
6190
6191 LSM_HOOK_INIT(task_create, selinux_task_create),
6192 LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6193 LSM_HOOK_INIT(cred_free, selinux_cred_free),
6194 LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6195 LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6196 LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6197 LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6198 LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6199 LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6200 LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6201 LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6202 LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6203 LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6204 LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6205 LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6206 LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6207 LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6208 LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6209 LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6210 LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6211 LSM_HOOK_INIT(task_kill, selinux_task_kill),
6212 LSM_HOOK_INIT(task_wait, selinux_task_wait),
6213 LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6214
6215 LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6216 LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6217
6218 LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6219 LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6220
6221 LSM_HOOK_INIT(msg_queue_alloc_security,
6222 selinux_msg_queue_alloc_security),
6223 LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6224 LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6225 LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6226 LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6227 LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6228
6229 LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6230 LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6231 LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6232 LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6233 LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6234
6235 LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6236 LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6237 LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6238 LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6239 LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6240
6241 LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6242
6243 LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6244 LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6245
6246 LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6247 LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6248 LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6249 LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6250 LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6251 LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6252 LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6253 LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6254
6255 LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6256 LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6257
6258 LSM_HOOK_INIT(socket_create, selinux_socket_create),
6259 LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6260 LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6261 LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6262 LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6263 LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6264 LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6265 LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6266 LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6267 LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6268 LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6269 LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6270 LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6271 LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6272 LSM_HOOK_INIT(socket_getpeersec_stream,
6273 selinux_socket_getpeersec_stream),
6274 LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6275 LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6276 LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6277 LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6278 LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6279 LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6280 LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6281 LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6282 LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6283 LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6284 LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6285 LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6286 LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6287 LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6288 LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6289 LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6290 LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6291 LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6292 LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6293
6294#ifdef CONFIG_SECURITY_NETWORK_XFRM
6295 LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6296 LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6297 LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6298 LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6299 LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6300 LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6301 selinux_xfrm_state_alloc_acquire),
6302 LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6303 LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6304 LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6305 LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6306 selinux_xfrm_state_pol_flow_match),
6307 LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6308#endif
6309
6310#ifdef CONFIG_KEYS
6311 LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6312 LSM_HOOK_INIT(key_free, selinux_key_free),
6313 LSM_HOOK_INIT(key_permission, selinux_key_permission),
6314 LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6315#endif
6316
6317#ifdef CONFIG_AUDIT
6318 LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6319 LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6320 LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6321 LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6322#endif
6323};
6324
6325static __init int selinux_init(void)
6326{
6327 if (!security_module_enable("selinux")) {
6328 selinux_enabled = 0;
6329 return 0;
6330 }
6331
6332 if (!selinux_enabled) {
6333 printk(KERN_INFO "SELinux: Disabled at boot.\n");
6334 return 0;
6335 }
6336
6337 printk(KERN_INFO "SELinux: Initializing.\n");
6338
6339 /* Set the security state for the initial task. */
6340 cred_init_security();
6341
6342 default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6343
6344 sel_inode_cache = kmem_cache_create("selinux_inode_security",
6345 sizeof(struct inode_security_struct),
6346 0, SLAB_PANIC, NULL);
6347 file_security_cache = kmem_cache_create("selinux_file_security",
6348 sizeof(struct file_security_struct),
6349 0, SLAB_PANIC, NULL);
6350 avc_init();
6351
6352 security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6353
6354 if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6355 panic("SELinux: Unable to register AVC netcache callback\n");
6356
6357 if (selinux_enforcing)
6358 printk(KERN_DEBUG "SELinux: Starting in enforcing mode\n");
6359 else
6360 printk(KERN_DEBUG "SELinux: Starting in permissive mode\n");
6361
6362 return 0;
6363}
6364
6365static void delayed_superblock_init(struct super_block *sb, void *unused)
6366{
6367 superblock_doinit(sb, NULL);
6368}
6369
6370void selinux_complete_init(void)
6371{
6372 printk(KERN_DEBUG "SELinux: Completing initialization.\n");
6373
6374 /* Set up any superblocks initialized prior to the policy load. */
6375 printk(KERN_DEBUG "SELinux: Setting up existing superblocks.\n");
6376 iterate_supers(delayed_superblock_init, NULL);
6377}
6378
6379/* SELinux requires early initialization in order to label
6380 all processes and objects when they are created. */
6381security_initcall(selinux_init);
6382
6383#if defined(CONFIG_NETFILTER)
6384
6385static struct nf_hook_ops selinux_nf_ops[] = {
6386 {
6387 .hook = selinux_ipv4_postroute,
6388 .pf = NFPROTO_IPV4,
6389 .hooknum = NF_INET_POST_ROUTING,
6390 .priority = NF_IP_PRI_SELINUX_LAST,
6391 },
6392 {
6393 .hook = selinux_ipv4_forward,
6394 .pf = NFPROTO_IPV4,
6395 .hooknum = NF_INET_FORWARD,
6396 .priority = NF_IP_PRI_SELINUX_FIRST,
6397 },
6398 {
6399 .hook = selinux_ipv4_output,
6400 .pf = NFPROTO_IPV4,
6401 .hooknum = NF_INET_LOCAL_OUT,
6402 .priority = NF_IP_PRI_SELINUX_FIRST,
6403 },
6404#if IS_ENABLED(CONFIG_IPV6)
6405 {
6406 .hook = selinux_ipv6_postroute,
6407 .pf = NFPROTO_IPV6,
6408 .hooknum = NF_INET_POST_ROUTING,
6409 .priority = NF_IP6_PRI_SELINUX_LAST,
6410 },
6411 {
6412 .hook = selinux_ipv6_forward,
6413 .pf = NFPROTO_IPV6,
6414 .hooknum = NF_INET_FORWARD,
6415 .priority = NF_IP6_PRI_SELINUX_FIRST,
6416 },
6417 {
6418 .hook = selinux_ipv6_output,
6419 .pf = NFPROTO_IPV6,
6420 .hooknum = NF_INET_LOCAL_OUT,
6421 .priority = NF_IP6_PRI_SELINUX_FIRST,
6422 },
6423#endif /* IPV6 */
6424};
6425
6426static int __init selinux_nf_ip_init(void)
6427{
6428 int err;
6429
6430 if (!selinux_enabled)
6431 return 0;
6432
6433 printk(KERN_DEBUG "SELinux: Registering netfilter hooks\n");
6434
6435 err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6436 if (err)
6437 panic("SELinux: nf_register_hooks: error %d\n", err);
6438
6439 return 0;
6440}
6441
6442__initcall(selinux_nf_ip_init);
6443
6444#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6445static void selinux_nf_ip_exit(void)
6446{
6447 printk(KERN_DEBUG "SELinux: Unregistering netfilter hooks\n");
6448
6449 nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6450}
6451#endif
6452
6453#else /* CONFIG_NETFILTER */
6454
6455#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6456#define selinux_nf_ip_exit()
6457#endif
6458
6459#endif /* CONFIG_NETFILTER */
6460
6461#ifdef CONFIG_SECURITY_SELINUX_DISABLE
6462static int selinux_disabled;
6463
6464int selinux_disable(void)
6465{
6466 if (ss_initialized) {
6467 /* Not permitted after initial policy load. */
6468 return -EINVAL;
6469 }
6470
6471 if (selinux_disabled) {
6472 /* Only do this once. */
6473 return -EINVAL;
6474 }
6475
6476 printk(KERN_INFO "SELinux: Disabled at runtime.\n");
6477
6478 selinux_disabled = 1;
6479 selinux_enabled = 0;
6480
6481 security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6482
6483 /* Try to destroy the avc node cache */
6484 avc_disable();
6485
6486 /* Unregister netfilter hooks. */
6487 selinux_nf_ip_exit();
6488
6489 /* Unregister selinuxfs. */
6490 exit_sel_fs();
6491
6492 return 0;
6493}
6494#endif