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