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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor LSM hooks.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#include <linux/lsm_hooks.h>
12#include <linux/moduleparam.h>
13#include <linux/mm.h>
14#include <linux/mman.h>
15#include <linux/mount.h>
16#include <linux/namei.h>
17#include <linux/ptrace.h>
18#include <linux/ctype.h>
19#include <linux/sysctl.h>
20#include <linux/sysfs.h>
21#include <linux/audit.h>
22#include <linux/user_namespace.h>
23#include <linux/netfilter_ipv4.h>
24#include <linux/netfilter_ipv6.h>
25#include <linux/zstd.h>
26#include <net/sock.h>
27#include <uapi/linux/mount.h>
28#include <uapi/linux/lsm.h>
29
30#include "include/af_unix.h"
31#include "include/af_inet.h"
32#include "include/apparmor.h"
33#include "include/apparmorfs.h"
34#include "include/audit.h"
35#include "include/capability.h"
36#include "include/cred.h"
37#include "include/crypto.h"
38#include "include/file.h"
39#include "include/ipc.h"
40#include "include/net.h"
41#include "include/path.h"
42#include "include/label.h"
43#include "include/policy.h"
44#include "include/policy_ns.h"
45#include "include/procattr.h"
46#include "include/mount.h"
47#include "include/secid.h"
48
49/* Flag indicating whether initialization completed */
50int apparmor_initialized;
51
52union aa_buffer {
53 struct list_head list;
54 DECLARE_FLEX_ARRAY(char, buffer);
55};
56
57struct aa_local_cache {
58 unsigned int hold;
59 unsigned int count;
60 struct list_head head;
61};
62
63#define RESERVE_COUNT 2
64static int reserve_count = RESERVE_COUNT;
65static int buffer_count;
66
67static LIST_HEAD(aa_global_buffers);
68static DEFINE_SPINLOCK(aa_buffers_lock);
69static DEFINE_PER_CPU(struct aa_local_cache, aa_local_buffers);
70
71/*
72 * LSM hook functions
73 */
74
75/*
76 * put the associated labels
77 */
78static void apparmor_cred_free(struct cred *cred)
79{
80 aa_put_label(cred_label(cred));
81 set_cred_label(cred, NULL);
82}
83
84/*
85 * allocate the apparmor part of blank credentials
86 */
87static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
88{
89 set_cred_label(cred, NULL);
90 return 0;
91}
92
93/*
94 * prepare new cred label for modification by prepare_cred block
95 */
96static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
97 gfp_t gfp)
98{
99 set_cred_label(new, aa_get_newest_label(cred_label(old)));
100 return 0;
101}
102
103/*
104 * transfer the apparmor data to a blank set of creds
105 */
106static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
107{
108 set_cred_label(new, aa_get_newest_label(cred_label(old)));
109}
110
111static void apparmor_task_free(struct task_struct *task)
112{
113
114 aa_free_task_ctx(task_ctx(task));
115}
116
117static int apparmor_task_alloc(struct task_struct *task,
118 u64 clone_flags)
119{
120 struct aa_task_ctx *new = task_ctx(task);
121
122 aa_dup_task_ctx(new, task_ctx(current));
123
124 return 0;
125}
126
127static int apparmor_ptrace_access_check(struct task_struct *child,
128 unsigned int mode)
129{
130 struct aa_label *tracer, *tracee;
131 const struct cred *cred;
132 int error;
133 bool needput;
134
135 cred = get_task_cred(child);
136 tracee = cred_label(cred); /* ref count on cred */
137 tracer = __begin_current_label_crit_section(&needput);
138 error = aa_may_ptrace(current_cred(), tracer, cred, tracee,
139 (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
140 : AA_PTRACE_TRACE);
141 __end_current_label_crit_section(tracer, needput);
142 put_cred(cred);
143
144 return error;
145}
146
147static int apparmor_ptrace_traceme(struct task_struct *parent)
148{
149 struct aa_label *tracer, *tracee;
150 const struct cred *cred;
151 int error;
152 bool needput;
153
154 tracee = __begin_current_label_crit_section(&needput);
155 cred = get_task_cred(parent);
156 tracer = cred_label(cred); /* ref count on cred */
157 error = aa_may_ptrace(cred, tracer, current_cred(), tracee,
158 AA_PTRACE_TRACE);
159 put_cred(cred);
160 __end_current_label_crit_section(tracee, needput);
161
162 return error;
163}
164
165/* Derived from security/commoncap.c:cap_capget */
166static int apparmor_capget(const struct task_struct *target, kernel_cap_t *effective,
167 kernel_cap_t *inheritable, kernel_cap_t *permitted)
168{
169 struct aa_label *label;
170 const struct cred *cred;
171
172 rcu_read_lock();
173 cred = __task_cred(target);
174 label = aa_get_newest_cred_label(cred);
175
176 /*
177 * cap_capget is stacked ahead of this and will
178 * initialize effective and permitted.
179 */
180 if (!unconfined(label)) {
181 struct aa_profile *profile;
182 struct label_it i;
183
184 label_for_each_confined(i, label, profile) {
185 kernel_cap_t allowed;
186
187 allowed = aa_profile_capget(profile);
188 *effective = cap_intersect(*effective, allowed);
189 *permitted = cap_intersect(*permitted, allowed);
190 }
191 }
192 rcu_read_unlock();
193 aa_put_label(label);
194
195 return 0;
196}
197
198static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
199 int cap, unsigned int opts)
200{
201 struct aa_label *label;
202 int error = 0;
203
204 label = aa_get_newest_cred_label(cred);
205 if (!unconfined(label))
206 error = aa_capable(cred, label, cap, opts);
207 aa_put_label(label);
208
209 return error;
210}
211
212/**
213 * common_perm - basic common permission check wrapper fn for paths
214 * @op: operation being checked
215 * @path: path to check permission of (NOT NULL)
216 * @mask: requested permissions mask
217 * @cond: conditional info for the permission request (NOT NULL)
218 *
219 * Returns: %0 else error code if error or permission denied
220 */
221static int common_perm(const char *op, const struct path *path, u32 mask,
222 struct path_cond *cond)
223{
224 struct aa_label *label;
225 int error = 0;
226 bool needput;
227
228 label = __begin_current_label_crit_section(&needput);
229 if (!unconfined(label))
230 error = aa_path_perm(op, current_cred(), label, path, 0, mask,
231 cond);
232 __end_current_label_crit_section(label, needput);
233
234 return error;
235}
236
237/**
238 * common_perm_cond - common permission wrapper around inode cond
239 * @op: operation being checked
240 * @path: location to check (NOT NULL)
241 * @mask: requested permissions mask
242 *
243 * Returns: %0 else error code if error or permission denied
244 */
245static int common_perm_cond(const char *op, const struct path *path, u32 mask)
246{
247 vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_idmap(path->mnt),
248 d_backing_inode(path->dentry));
249 struct path_cond cond = {
250 vfsuid_into_kuid(vfsuid),
251 d_backing_inode(path->dentry)->i_mode
252 };
253
254 if (!path_mediated_fs(path->dentry))
255 return 0;
256
257 return common_perm(op, path, mask, &cond);
258}
259
260/**
261 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
262 * @op: operation being checked
263 * @dir: directory of the dentry (NOT NULL)
264 * @dentry: dentry to check (NOT NULL)
265 * @mask: requested permissions mask
266 * @cond: conditional info for the permission request (NOT NULL)
267 *
268 * Returns: %0 else error code if error or permission denied
269 */
270static int common_perm_dir_dentry(const char *op, const struct path *dir,
271 struct dentry *dentry, u32 mask,
272 struct path_cond *cond)
273{
274 struct path path = { .mnt = dir->mnt, .dentry = dentry };
275
276 return common_perm(op, &path, mask, cond);
277}
278
279/**
280 * common_perm_rm - common permission wrapper for operations doing rm
281 * @op: operation being checked
282 * @dir: directory that the dentry is in (NOT NULL)
283 * @dentry: dentry being rm'd (NOT NULL)
284 * @mask: requested permission mask
285 *
286 * Returns: %0 else error code if error or permission denied
287 */
288static int common_perm_rm(const char *op, const struct path *dir,
289 struct dentry *dentry, u32 mask)
290{
291 struct inode *inode = d_backing_inode(dentry);
292 struct path_cond cond = { };
293 vfsuid_t vfsuid;
294
295 if (!inode || !path_mediated_fs(dentry))
296 return 0;
297
298 vfsuid = i_uid_into_vfsuid(mnt_idmap(dir->mnt), inode);
299 cond.uid = vfsuid_into_kuid(vfsuid);
300 cond.mode = inode->i_mode;
301
302 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
303}
304
305/**
306 * common_perm_create - common permission wrapper for operations doing create
307 * @op: operation being checked
308 * @dir: directory that dentry will be created in (NOT NULL)
309 * @dentry: dentry to create (NOT NULL)
310 * @mask: request permission mask
311 * @mode: created file mode
312 *
313 * Returns: %0 else error code if error or permission denied
314 */
315static int common_perm_create(const char *op, const struct path *dir,
316 struct dentry *dentry, u32 mask, umode_t mode)
317{
318 struct path_cond cond = { current_fsuid(), mode };
319
320 if (!path_mediated_fs(dir->dentry))
321 return 0;
322
323 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
324}
325
326static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
327{
328 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
329}
330
331static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
332 umode_t mode)
333{
334 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
335 S_IFDIR);
336}
337
338static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
339{
340 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
341}
342
343static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
344 umode_t mode, unsigned int dev)
345{
346 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
347}
348
349static int apparmor_path_truncate(const struct path *path)
350{
351 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
352}
353
354static int apparmor_file_truncate(struct file *file)
355{
356 return apparmor_path_truncate(&file->f_path);
357}
358
359static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
360 const char *old_name)
361{
362 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
363 S_IFLNK);
364}
365
366static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
367 struct dentry *new_dentry)
368{
369 struct aa_label *label;
370 int error = 0;
371 bool needput;
372
373 if (!path_mediated_fs(old_dentry))
374 return 0;
375
376 label = begin_current_label_crit_section(&needput);
377 if (!unconfined(label))
378 error = aa_path_link(current_cred(), label, old_dentry, new_dir,
379 new_dentry);
380 end_current_label_crit_section(label, needput);
381
382 return error;
383}
384
385static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
386 const struct path *new_dir, struct dentry *new_dentry,
387 const unsigned int flags)
388{
389 struct aa_label *label;
390 int error = 0;
391 bool needput;
392
393 if (!path_mediated_fs(old_dentry))
394 return 0;
395 if ((flags & RENAME_EXCHANGE) && !path_mediated_fs(new_dentry))
396 return 0;
397
398 label = begin_current_label_crit_section(&needput);
399 if (!unconfined(label)) {
400 const struct mnt_idmap *idmap = mnt_idmap(old_dir->mnt);
401 vfsuid_t vfsuid;
402 struct path old_path = { .mnt = old_dir->mnt,
403 .dentry = old_dentry };
404 struct path new_path = { .mnt = new_dir->mnt,
405 .dentry = new_dentry };
406 struct path_cond cond = {
407 .mode = d_backing_inode(old_dentry)->i_mode
408 };
409 vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(old_dentry));
410 cond.uid = vfsuid_into_kuid(vfsuid);
411
412 if (flags & RENAME_EXCHANGE) {
413 struct path_cond cond_exchange = {
414 .mode = d_backing_inode(new_dentry)->i_mode,
415 };
416 vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(new_dentry));
417 cond_exchange.uid = vfsuid_into_kuid(vfsuid);
418
419 error = aa_path_perm(OP_RENAME_SRC, current_cred(),
420 label, &new_path, 0,
421 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
422 AA_MAY_SETATTR | AA_MAY_DELETE,
423 &cond_exchange);
424 if (!error)
425 error = aa_path_perm(OP_RENAME_DEST, current_cred(),
426 label, &old_path,
427 0, MAY_WRITE | AA_MAY_SETATTR |
428 AA_MAY_CREATE, &cond_exchange);
429 }
430
431 if (!error)
432 error = aa_path_perm(OP_RENAME_SRC, current_cred(),
433 label, &old_path, 0,
434 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
435 AA_MAY_SETATTR | AA_MAY_DELETE,
436 &cond);
437 if (!error)
438 error = aa_path_perm(OP_RENAME_DEST, current_cred(),
439 label, &new_path,
440 0, MAY_WRITE | AA_MAY_SETATTR |
441 AA_MAY_CREATE, &cond);
442
443 }
444 end_current_label_crit_section(label, needput);
445
446 return error;
447}
448
449static int apparmor_path_chmod(const struct path *path, umode_t mode)
450{
451 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
452}
453
454static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
455{
456 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
457}
458
459static int apparmor_inode_getattr(const struct path *path)
460{
461 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
462}
463
464static int apparmor_file_open(struct file *file)
465{
466 struct aa_file_ctx *fctx = file_ctx(file);
467 struct aa_label *label;
468 int error = 0;
469 bool needput;
470
471 if (!path_mediated_fs(file->f_path.dentry))
472 return 0;
473
474 /* If in exec, permission is handled by bprm hooks.
475 * Cache permissions granted by the previous exec check, with
476 * implicit read and executable mmap which are required to
477 * actually execute the image.
478 *
479 * Illogically, FMODE_EXEC is in f_flags, not f_mode.
480 */
481 if (file->f_flags & __FMODE_EXEC) {
482 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
483 return 0;
484 }
485
486 label = aa_get_newest_cred_label_condref(file->f_cred, &needput);
487 if (!unconfined(label)) {
488 const struct mnt_idmap *idmap = file_mnt_idmap(file);
489 struct inode *inode = file_inode(file);
490 vfsuid_t vfsuid;
491 struct path_cond cond = {
492 .mode = inode->i_mode,
493 };
494 vfsuid = i_uid_into_vfsuid(idmap, inode);
495 cond.uid = vfsuid_into_kuid(vfsuid);
496
497 error = aa_path_perm(OP_OPEN, file->f_cred,
498 label, &file->f_path, 0,
499 aa_map_file_to_perms(file), &cond);
500 /* todo cache full allowed permissions set and state */
501 fctx->allow = aa_map_file_to_perms(file);
502 }
503 aa_put_label_condref(label, needput);
504
505 return error;
506}
507
508static int apparmor_file_alloc_security(struct file *file)
509{
510 struct aa_file_ctx *ctx = file_ctx(file);
511 bool needput;
512 struct aa_label *label = begin_current_label_crit_section(&needput);
513
514 spin_lock_init(&ctx->lock);
515 rcu_assign_pointer(ctx->label, aa_get_label(label));
516 end_current_label_crit_section(label, needput);
517 return 0;
518}
519
520static void apparmor_file_free_security(struct file *file)
521{
522 struct aa_file_ctx *ctx = file_ctx(file);
523
524 if (ctx)
525 aa_put_label(rcu_access_pointer(ctx->label));
526}
527
528static int common_file_perm(const char *op, struct file *file, u32 mask)
529{
530 struct aa_label *label;
531 bool needput;
532 int error = 0;
533
534 label = begin_current_label_crit_section(&needput);
535 error = aa_file_perm(op, current_cred(), label, file, mask, false);
536 end_current_label_crit_section(label, needput);
537
538 return error;
539}
540
541static int apparmor_file_receive(struct file *file)
542{
543 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
544}
545
546static int apparmor_file_permission(struct file *file, int mask)
547{
548 return common_file_perm(OP_FPERM, file, mask);
549}
550
551static int apparmor_file_lock(struct file *file, unsigned int cmd)
552{
553 u32 mask = AA_MAY_LOCK;
554
555 if (cmd == F_WRLCK)
556 mask |= MAY_WRITE;
557
558 return common_file_perm(OP_FLOCK, file, mask);
559}
560
561static int common_mmap(const char *op, struct file *file, unsigned long prot,
562 unsigned long flags)
563{
564 int mask = 0;
565
566 if (!file || !file_ctx(file))
567 return 0;
568
569 if (prot & PROT_READ)
570 mask |= MAY_READ;
571 /*
572 * Private mappings don't require write perms since they don't
573 * write back to the files
574 */
575 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
576 mask |= MAY_WRITE;
577 if (prot & PROT_EXEC)
578 mask |= AA_EXEC_MMAP;
579
580 return common_file_perm(op, file, mask);
581}
582
583static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
584 unsigned long prot, unsigned long flags)
585{
586 return common_mmap(OP_FMMAP, file, prot, flags);
587}
588
589static int apparmor_file_mprotect(struct vm_area_struct *vma,
590 unsigned long reqprot, unsigned long prot)
591{
592 return common_mmap(OP_FMPROT, vma->vm_file, prot,
593 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
594}
595
596#ifdef CONFIG_IO_URING
597static const char *audit_uring_mask(u32 mask)
598{
599 if (mask & AA_MAY_CREATE_SQPOLL)
600 return "sqpoll";
601 if (mask & AA_MAY_OVERRIDE_CRED)
602 return "override_creds";
603 return "";
604}
605
606static void audit_uring_cb(struct audit_buffer *ab, void *va)
607{
608 struct apparmor_audit_data *ad = aad_of_va(va);
609
610 if (ad->request & AA_URING_PERM_MASK) {
611 audit_log_format(ab, " requested=\"%s\"",
612 audit_uring_mask(ad->request));
613 if (ad->denied & AA_URING_PERM_MASK) {
614 audit_log_format(ab, " denied=\"%s\"",
615 audit_uring_mask(ad->denied));
616 }
617 }
618 if (ad->uring.target) {
619 audit_log_format(ab, " tcontext=");
620 aa_label_xaudit(ab, labels_ns(ad->subj_label),
621 ad->uring.target,
622 FLAGS_NONE, GFP_ATOMIC);
623 }
624}
625
626static int profile_uring(struct aa_profile *profile, u32 request,
627 struct aa_label *new, int cap,
628 struct apparmor_audit_data *ad)
629{
630 unsigned int state;
631 struct aa_ruleset *rules;
632 int error = 0;
633
634 AA_BUG(!profile);
635
636 rules = profile->label.rules[0];
637 state = RULE_MEDIATES(rules, AA_CLASS_IO_URING);
638 if (state) {
639 struct aa_perms perms = { };
640
641 if (new) {
642 aa_label_match(profile, rules, new, state,
643 false, request, &perms);
644 } else {
645 perms = *aa_lookup_perms(rules->policy, state);
646 }
647 aa_apply_modes_to_perms(profile, &perms);
648 error = aa_check_perms(profile, &perms, request, ad,
649 audit_uring_cb);
650 }
651
652 return error;
653}
654
655/**
656 * apparmor_uring_override_creds - check the requested cred override
657 * @new: the target creds
658 *
659 * Check to see if the current task is allowed to override it's credentials
660 * to service an io_uring operation.
661 */
662static int apparmor_uring_override_creds(const struct cred *new)
663{
664 struct aa_profile *profile;
665 struct aa_label *label;
666 int error;
667 bool needput;
668 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING,
669 OP_URING_OVERRIDE);
670
671 ad.uring.target = cred_label(new);
672 label = __begin_current_label_crit_section(&needput);
673 error = fn_for_each(label, profile,
674 profile_uring(profile, AA_MAY_OVERRIDE_CRED,
675 cred_label(new), CAP_SYS_ADMIN, &ad));
676 __end_current_label_crit_section(label, needput);
677
678 return error;
679}
680
681/**
682 * apparmor_uring_sqpoll - check if a io_uring polling thread can be created
683 *
684 * Check to see if the current task is allowed to create a new io_uring
685 * kernel polling thread.
686 */
687static int apparmor_uring_sqpoll(void)
688{
689 struct aa_profile *profile;
690 struct aa_label *label;
691 int error;
692 bool needput;
693 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING,
694 OP_URING_SQPOLL);
695
696 label = __begin_current_label_crit_section(&needput);
697 error = fn_for_each(label, profile,
698 profile_uring(profile, AA_MAY_CREATE_SQPOLL,
699 NULL, CAP_SYS_ADMIN, &ad));
700 __end_current_label_crit_section(label, needput);
701
702 return error;
703}
704#endif /* CONFIG_IO_URING */
705
706static int apparmor_sb_mount(const char *dev_name, const struct path *path,
707 const char *type, unsigned long flags, void *data)
708{
709 struct aa_label *label;
710 int error = 0;
711 bool needput;
712
713 /* Discard magic */
714 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
715 flags &= ~MS_MGC_MSK;
716
717 flags &= ~AA_MS_IGNORE_MASK;
718
719 label = __begin_current_label_crit_section(&needput);
720 if (!unconfined(label)) {
721 if (flags & MS_REMOUNT)
722 error = aa_remount(current_cred(), label, path, flags,
723 data);
724 else if (flags & MS_BIND)
725 error = aa_bind_mount(current_cred(), label, path,
726 dev_name, flags);
727 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
728 MS_UNBINDABLE))
729 error = aa_mount_change_type(current_cred(), label,
730 path, flags);
731 else if (flags & MS_MOVE)
732 error = aa_move_mount_old(current_cred(), label, path,
733 dev_name);
734 else
735 error = aa_new_mount(current_cred(), label, dev_name,
736 path, type, flags, data);
737 }
738 __end_current_label_crit_section(label, needput);
739
740 return error;
741}
742
743static int apparmor_move_mount(const struct path *from_path,
744 const struct path *to_path)
745{
746 struct aa_label *label;
747 int error = 0;
748 bool needput;
749
750 label = __begin_current_label_crit_section(&needput);
751 if (!unconfined(label))
752 error = aa_move_mount(current_cred(), label, from_path,
753 to_path);
754 __end_current_label_crit_section(label, needput);
755
756 return error;
757}
758
759static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
760{
761 struct aa_label *label;
762 int error = 0;
763 bool needput;
764
765 label = __begin_current_label_crit_section(&needput);
766 if (!unconfined(label))
767 error = aa_umount(current_cred(), label, mnt, flags);
768 __end_current_label_crit_section(label, needput);
769
770 return error;
771}
772
773static int apparmor_sb_pivotroot(const struct path *old_path,
774 const struct path *new_path)
775{
776 struct aa_label *label;
777 int error = 0;
778
779 label = aa_get_current_label();
780 if (!unconfined(label))
781 error = aa_pivotroot(current_cred(), label, old_path, new_path);
782 aa_put_label(label);
783
784 return error;
785}
786
787static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx,
788 u32 *size, u32 flags)
789{
790 int error = -ENOENT;
791 struct aa_task_ctx *ctx = task_ctx(current);
792 struct aa_label *label = NULL;
793 char *value = NULL;
794
795 switch (attr) {
796 case LSM_ATTR_CURRENT:
797 label = aa_get_newest_label(cred_label(current_cred()));
798 break;
799 case LSM_ATTR_PREV:
800 if (ctx->previous)
801 label = aa_get_newest_label(ctx->previous);
802 break;
803 case LSM_ATTR_EXEC:
804 if (ctx->onexec)
805 label = aa_get_newest_label(ctx->onexec);
806 break;
807 default:
808 error = -EOPNOTSUPP;
809 break;
810 }
811
812 if (label) {
813 error = aa_getprocattr(label, &value, false);
814 if (error > 0)
815 error = lsm_fill_user_ctx(lx, size, value, error,
816 LSM_ID_APPARMOR, 0);
817 kfree(value);
818 }
819
820 aa_put_label(label);
821
822 if (error < 0)
823 return error;
824 return 1;
825}
826
827static int apparmor_getprocattr(struct task_struct *task, const char *name,
828 char **value)
829{
830 int error = -ENOENT;
831 struct aa_label *label = NULL;
832
833 rcu_read_lock();
834 if (strcmp(name, "current") == 0)
835 label = aa_get_newest_cred_label(__task_cred(task));
836 else if (strcmp(name, "prev") == 0 && task_ctx(task)->previous)
837 label = aa_get_newest_label(task_ctx(task)->previous);
838 else if (strcmp(name, "exec") == 0 && task_ctx(task)->onexec)
839 label = aa_get_newest_label(task_ctx(task)->onexec);
840 else
841 error = -EINVAL;
842 rcu_read_unlock();
843
844 if (label)
845 error = aa_getprocattr(label, value, true);
846
847 aa_put_label(label);
848
849 return error;
850}
851
852static int do_setattr(u64 attr, void *value, size_t size)
853{
854 char *command, *largs = NULL, *args = value;
855 size_t arg_size;
856 int error;
857 bool needput;
858 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE,
859 OP_SETPROCATTR);
860
861 if (size == 0)
862 return -EINVAL;
863
864 /* AppArmor requires that the buffer must be null terminated atm */
865 if (args[size - 1] != '\0') {
866 largs = args = kmemdup_nul(value, size, GFP_KERNEL);
867 if (!args)
868 return -ENOMEM;
869 }
870
871 error = -EINVAL;
872 args = strim(args);
873 command = strsep(&args, " ");
874 if (!args)
875 goto out;
876 args = skip_spaces(args);
877 if (!*args)
878 goto out;
879
880 arg_size = size - (args - (largs ? largs : (char *) value));
881 if (attr == LSM_ATTR_CURRENT) {
882 if (strcmp(command, "changehat") == 0) {
883 error = aa_setprocattr_changehat(args, arg_size,
884 AA_CHANGE_NOFLAGS);
885 } else if (strcmp(command, "permhat") == 0) {
886 error = aa_setprocattr_changehat(args, arg_size,
887 AA_CHANGE_TEST);
888 } else if (strcmp(command, "changeprofile") == 0) {
889 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
890 } else if (strcmp(command, "permprofile") == 0) {
891 error = aa_change_profile(args, AA_CHANGE_TEST);
892 } else if (strcmp(command, "stack") == 0) {
893 error = aa_change_profile(args, AA_CHANGE_STACK);
894 } else
895 goto fail;
896 } else if (attr == LSM_ATTR_EXEC) {
897 if (strcmp(command, "exec") == 0)
898 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
899 else if (strcmp(command, "stack") == 0)
900 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
901 AA_CHANGE_STACK));
902 else
903 goto fail;
904 } else
905 /* only support the "current" and "exec" process attributes */
906 goto fail;
907
908 if (!error)
909 error = size;
910out:
911 kfree(largs);
912 return error;
913
914fail:
915 ad.subj_label = begin_current_label_crit_section(&needput);
916 if (attr == LSM_ATTR_CURRENT)
917 ad.info = "current";
918 else if (attr == LSM_ATTR_EXEC)
919 ad.info = "exec";
920 else
921 ad.info = "invalid";
922 ad.error = error = -EINVAL;
923 aa_audit_msg(AUDIT_APPARMOR_DENIED, &ad, NULL);
924 end_current_label_crit_section(ad.subj_label, needput);
925 goto out;
926}
927
928static int apparmor_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
929 u32 size, u32 flags)
930{
931 int rc;
932
933 if (attr != LSM_ATTR_CURRENT && attr != LSM_ATTR_EXEC)
934 return -EOPNOTSUPP;
935
936 rc = do_setattr(attr, ctx->ctx, ctx->ctx_len);
937 if (rc > 0)
938 return 0;
939 return rc;
940}
941
942static int apparmor_setprocattr(const char *name, void *value,
943 size_t size)
944{
945 int attr = lsm_name_to_attr(name);
946
947 if (attr)
948 return do_setattr(attr, value, size);
949 return -EINVAL;
950}
951
952/**
953 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
954 * @bprm: binprm for the exec (NOT NULL)
955 */
956static void apparmor_bprm_committing_creds(const struct linux_binprm *bprm)
957{
958 struct aa_label *label = aa_current_raw_label();
959 struct aa_label *new_label = cred_label(bprm->cred);
960
961 /* bail out if unconfined or not changing profile */
962 if ((new_label->proxy == label->proxy) ||
963 (unconfined(new_label)))
964 return;
965
966 aa_inherit_files(bprm->cred, current->files);
967
968 current->pdeath_signal = 0;
969
970 /* reset soft limits and set hard limits for the new label */
971 __aa_transition_rlimits(label, new_label);
972}
973
974/**
975 * apparmor_bprm_committed_creds() - do cleanup after new creds committed
976 * @bprm: binprm for the exec (NOT NULL)
977 */
978static void apparmor_bprm_committed_creds(const struct linux_binprm *bprm)
979{
980 /* clear out temporary/transitional state from the context */
981 aa_clear_task_ctx_trans(task_ctx(current));
982
983 return;
984}
985
986static void apparmor_current_getlsmprop_subj(struct lsm_prop *prop)
987{
988 struct aa_label *label;
989 bool needput;
990
991 label = __begin_current_label_crit_section(&needput);
992 prop->apparmor.label = label;
993 __end_current_label_crit_section(label, needput);
994}
995
996static void apparmor_task_getlsmprop_obj(struct task_struct *p,
997 struct lsm_prop *prop)
998{
999 struct aa_label *label = aa_get_task_label(p);
1000
1001 prop->apparmor.label = label;
1002 aa_put_label(label);
1003}
1004
1005static int apparmor_task_setrlimit(struct task_struct *task,
1006 unsigned int resource, struct rlimit *new_rlim)
1007{
1008 struct aa_label *label;
1009 int error = 0;
1010 bool needput;
1011
1012 label = __begin_current_label_crit_section(&needput);
1013
1014 if (!unconfined(label))
1015 error = aa_task_setrlimit(current_cred(), label, task,
1016 resource, new_rlim);
1017 __end_current_label_crit_section(label, needput);
1018
1019 return error;
1020}
1021
1022static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
1023 int sig, const struct cred *cred)
1024{
1025 const struct cred *tc;
1026 struct aa_label *cl, *tl;
1027 int error;
1028 bool needput;
1029
1030 tc = get_task_cred(target);
1031 tl = aa_get_newest_cred_label(tc);
1032 if (cred) {
1033 /*
1034 * Dealing with USB IO specific behavior
1035 */
1036 cl = aa_get_newest_cred_label(cred);
1037 error = aa_may_signal(cred, cl, tc, tl, sig);
1038 aa_put_label(cl);
1039 } else {
1040 cl = __begin_current_label_crit_section(&needput);
1041 error = aa_may_signal(current_cred(), cl, tc, tl, sig);
1042 __end_current_label_crit_section(cl, needput);
1043 }
1044 aa_put_label(tl);
1045 put_cred(tc);
1046
1047 return error;
1048}
1049
1050static int apparmor_userns_create(const struct cred *cred)
1051{
1052 struct aa_label *label;
1053 struct aa_profile *profile;
1054 int error = 0;
1055 bool needput;
1056 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_TASK, AA_CLASS_NS,
1057 OP_USERNS_CREATE);
1058
1059 ad.subj_cred = current_cred();
1060
1061 label = begin_current_label_crit_section(&needput);
1062 if (!unconfined(label)) {
1063 error = fn_for_each(label, profile,
1064 aa_profile_ns_perm(profile, &ad,
1065 AA_USERNS_CREATE));
1066 }
1067 end_current_label_crit_section(label, needput);
1068
1069 return error;
1070}
1071
1072static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t gfp)
1073{
1074 struct aa_sk_ctx *ctx = aa_sock(sk);
1075 struct aa_label *label;
1076 bool needput;
1077
1078 label = __begin_current_label_crit_section(&needput);
1079 //spin_lock_init(&ctx->lock);
1080 rcu_assign_pointer(ctx->label, aa_get_label(label));
1081 rcu_assign_pointer(ctx->peer, NULL);
1082 rcu_assign_pointer(ctx->peer_lastupdate, NULL);
1083 __end_current_label_crit_section(label, needput);
1084 return 0;
1085}
1086
1087static void apparmor_sk_free_security(struct sock *sk)
1088{
1089 struct aa_sk_ctx *ctx = aa_sock(sk);
1090
1091 /* dead these won't be updated any more */
1092 aa_put_label(rcu_dereference_protected(ctx->label, true));
1093 aa_put_label(rcu_dereference_protected(ctx->peer, true));
1094 aa_put_label(rcu_dereference_protected(ctx->peer_lastupdate, true));
1095}
1096
1097/**
1098 * apparmor_sk_clone_security - clone the sk_security field
1099 * @sk: sock to have security cloned
1100 * @newsk: sock getting clone
1101 */
1102static void apparmor_sk_clone_security(const struct sock *sk,
1103 struct sock *newsk)
1104{
1105 struct aa_sk_ctx *ctx = aa_sock(sk);
1106 struct aa_sk_ctx *new = aa_sock(newsk);
1107
1108 /* not actually in use yet */
1109 if (rcu_access_pointer(ctx->label) != rcu_access_pointer(new->label)) {
1110 aa_put_label(rcu_dereference_protected(new->label, true));
1111 rcu_assign_pointer(new->label, aa_get_label_rcu(&ctx->label));
1112 }
1113
1114 if (rcu_access_pointer(ctx->peer) != rcu_access_pointer(new->peer)) {
1115 aa_put_label(rcu_dereference_protected(new->peer, true));
1116 rcu_assign_pointer(new->peer, aa_get_label_rcu(&ctx->peer));
1117 }
1118
1119 if (rcu_access_pointer(ctx->peer_lastupdate) != rcu_access_pointer(new->peer_lastupdate)) {
1120 aa_put_label(rcu_dereference_protected(new->peer_lastupdate, true));
1121 rcu_assign_pointer(new->peer_lastupdate,
1122 aa_get_label_rcu(&ctx->peer_lastupdate));
1123 }
1124}
1125
1126static int unix_connect_perm(const struct cred *cred, struct aa_label *label,
1127 struct sock *sk, struct sock *peer_sk)
1128{
1129 struct aa_sk_ctx *peer_ctx = aa_sock(peer_sk);
1130 int error;
1131
1132 error = aa_unix_peer_perm(cred, label, OP_CONNECT,
1133 (AA_MAY_CONNECT | AA_MAY_SEND | AA_MAY_RECEIVE),
1134 sk, peer_sk,
1135 rcu_dereference_protected(peer_ctx->label,
1136 lockdep_is_held(&unix_sk(peer_sk)->lock)));
1137 if (!is_unix_fs(peer_sk)) {
1138 last_error(error,
1139 aa_unix_peer_perm(cred,
1140 rcu_dereference_protected(peer_ctx->label,
1141 lockdep_is_held(&unix_sk(peer_sk)->lock)),
1142 OP_CONNECT,
1143 (AA_MAY_ACCEPT | AA_MAY_SEND | AA_MAY_RECEIVE),
1144 peer_sk, sk, label));
1145 }
1146
1147 return error;
1148}
1149
1150/* lockdep check in unix_connect_perm - push sks here to check */
1151static void unix_connect_peers(struct aa_sk_ctx *sk_ctx,
1152 struct aa_sk_ctx *peer_ctx)
1153{
1154 /* Cross reference the peer labels for SO_PEERSEC */
1155 struct aa_label *label = rcu_dereference_protected(sk_ctx->label, true);
1156
1157 aa_get_label(label);
1158 aa_put_label(rcu_dereference_protected(peer_ctx->peer,
1159 true));
1160 rcu_assign_pointer(peer_ctx->peer, label); /* transfer cnt */
1161
1162 label = aa_get_label(rcu_dereference_protected(peer_ctx->label,
1163 true));
1164 //spin_unlock(&peer_ctx->lock);
1165
1166 //spin_lock(&sk_ctx->lock);
1167 aa_put_label(rcu_dereference_protected(sk_ctx->peer,
1168 true));
1169 aa_put_label(rcu_dereference_protected(sk_ctx->peer_lastupdate,
1170 true));
1171
1172 rcu_assign_pointer(sk_ctx->peer, aa_get_label(label));
1173 rcu_assign_pointer(sk_ctx->peer_lastupdate, label); /* transfer cnt */
1174 //spin_unlock(&sk_ctx->lock);
1175}
1176
1177/**
1178 * apparmor_unix_stream_connect - check perms before making unix domain conn
1179 * @sk: sk attempting to connect
1180 * @peer_sk: sk that is accepting the connection
1181 * @newsk: new sk created for this connection
1182 * peer is locked when this hook is called
1183 *
1184 * Return:
1185 * 0 if connection is permitted
1186 * error code on denial or failure
1187 */
1188static int apparmor_unix_stream_connect(struct sock *sk, struct sock *peer_sk,
1189 struct sock *newsk)
1190{
1191 struct aa_sk_ctx *sk_ctx = aa_sock(sk);
1192 struct aa_sk_ctx *peer_ctx = aa_sock(peer_sk);
1193 struct aa_sk_ctx *new_ctx = aa_sock(newsk);
1194 struct aa_label *label;
1195 int error;
1196 bool needput;
1197
1198 label = __begin_current_label_crit_section(&needput);
1199 error = unix_connect_perm(current_cred(), label, sk, peer_sk);
1200 __end_current_label_crit_section(label, needput);
1201
1202 if (error)
1203 return error;
1204
1205 /* newsk doesn't go through post_create, but does go through
1206 * security_sk_alloc()
1207 */
1208 rcu_assign_pointer(new_ctx->label,
1209 aa_get_label(rcu_dereference_protected(peer_ctx->label,
1210 true)));
1211
1212 /* Cross reference the peer labels for SO_PEERSEC */
1213 unix_connect_peers(sk_ctx, new_ctx);
1214
1215 return 0;
1216}
1217
1218/**
1219 * apparmor_unix_may_send - check perms before conn or sending unix dgrams
1220 * @sock: socket sending the message
1221 * @peer: socket message is being send to
1222 *
1223 * Performs bidirectional permission checks for Unix domain socket communication:
1224 * 1. Verifies sender has AA_MAY_SEND to target socket
1225 * 2. Verifies receiver has AA_MAY_RECEIVE from source socket
1226 *
1227 * sock and peer are locked when this hook is called
1228 * called by: dgram_connect peer setup but path not copied to newsk
1229 *
1230 * Return:
1231 * 0 if transmission is permitted
1232 * error code on denial or failure
1233 */
1234static int apparmor_unix_may_send(struct socket *sock, struct socket *peer)
1235{
1236 struct aa_sk_ctx *peer_ctx = aa_sock(peer->sk);
1237 struct aa_label *label;
1238 int error;
1239 bool needput;
1240
1241 label = __begin_current_label_crit_section(&needput);
1242 error = xcheck(aa_unix_peer_perm(current_cred(),
1243 label, OP_SENDMSG, AA_MAY_SEND,
1244 sock->sk, peer->sk,
1245 rcu_dereference_protected(peer_ctx->label,
1246 true)),
1247 aa_unix_peer_perm(peer->file ? peer->file->f_cred : NULL,
1248 rcu_dereference_protected(peer_ctx->label,
1249 true),
1250 OP_SENDMSG, AA_MAY_RECEIVE, peer->sk,
1251 sock->sk, label));
1252 __end_current_label_crit_section(label, needput);
1253
1254 return error;
1255}
1256
1257static int apparmor_socket_create(int family, int type, int protocol, int kern)
1258{
1259 struct aa_label *label;
1260 int error = 0;
1261 bool needput;
1262
1263 AA_BUG(in_interrupt());
1264
1265 if (kern)
1266 return 0;
1267
1268 label = begin_current_label_crit_section(&needput);
1269 if (!unconfined(label)) {
1270 switch (family) {
1271 case PF_UNIX:
1272 error = aa_unix_create_perm(label, family, type,
1273 protocol);
1274 break;
1275 case PF_INET:
1276 case PF_INET6:
1277 error = aa_inet_create_perm(label, family, type,
1278 protocol);
1279 break;
1280 default:
1281 error = aa_af_perm(current_cred(), label, OP_CREATE,
1282 AA_MAY_CREATE, family, type,
1283 protocol);
1284 }
1285 }
1286 end_current_label_crit_section(label, needput);
1287
1288 return error;
1289}
1290
1291/**
1292 * apparmor_socket_post_create - setup the per-socket security struct
1293 * @sock: socket that is being setup
1294 * @family: family of socket being created
1295 * @type: type of the socket
1296 * @protocol: protocol of the socket
1297 * @kern: socket is a special kernel socket
1298 *
1299 * Note:
1300 * - kernel sockets labeled kernel_t used to use unconfined
1301 * - socket may not have sk here if created with sock_create_lite or
1302 * sock_alloc. These should be accept cases which will be handled in
1303 * sock_graft.
1304 */
1305static int apparmor_socket_post_create(struct socket *sock, int family,
1306 int type, int protocol, int kern)
1307{
1308 struct aa_label *label;
1309
1310 if (kern) {
1311 label = aa_get_label(kernel_t);
1312 } else
1313 label = aa_get_current_label();
1314
1315 if (sock->sk) {
1316 struct aa_sk_ctx *ctx = aa_sock(sock->sk);
1317
1318 /* still not live */
1319 aa_put_label(rcu_dereference_protected(ctx->label, true));
1320 rcu_assign_pointer(ctx->label, aa_get_label(label));
1321 }
1322 aa_put_label(label);
1323
1324 return 0;
1325}
1326
1327static int apparmor_socket_socketpair(struct socket *socka,
1328 struct socket *sockb)
1329{
1330 struct aa_sk_ctx *a_ctx = aa_sock(socka->sk);
1331 struct aa_sk_ctx *b_ctx = aa_sock(sockb->sk);
1332 struct aa_label *label;
1333 bool needput;
1334
1335 /* socks not live yet - initial values set in sk_alloc */
1336 label = begin_current_label_crit_section(&needput);
1337 if (rcu_access_pointer(a_ctx->label) != label) {
1338 AA_BUG("a_ctx != label");
1339 aa_put_label(rcu_dereference_protected(a_ctx->label, true));
1340 rcu_assign_pointer(a_ctx->label, aa_get_label(label));
1341 }
1342 if (rcu_access_pointer(b_ctx->label) != label) {
1343 AA_BUG("b_ctx != label");
1344 aa_put_label(rcu_dereference_protected(b_ctx->label, true));
1345 rcu_assign_pointer(b_ctx->label, aa_get_label(label));
1346 }
1347
1348 if (socka->sk->sk_family == PF_UNIX) {
1349 /* unix socket pairs by-pass unix_stream_connect */
1350 unix_connect_peers(a_ctx, b_ctx);
1351 }
1352 end_current_label_crit_section(label, needput);
1353
1354 return 0;
1355}
1356
1357/**
1358 * apparmor_socket_bind - check perms before bind addr to socket
1359 * @sock: socket to bind the address to (must be non-NULL)
1360 * @address: address that is being bound (must be non-NULL)
1361 * @addrlen: length of @address
1362 *
1363 * Performs security checks before allowing a socket to bind to an address.
1364 * Handles Unix domain sockets specially through aa_unix_bind_perm().
1365 * For other socket families, uses generic permission check via aa_sk_perm().
1366 *
1367 * Return:
1368 * 0 if binding is permitted
1369 * error code on denial or invalid parameters
1370 */
1371static int apparmor_socket_bind(struct socket *sock,
1372 struct sockaddr *address, int addrlen)
1373{
1374 AA_BUG(!sock);
1375 AA_BUG(!sock->sk);
1376 AA_BUG(!address);
1377 AA_BUG(in_interrupt());
1378
1379 switch (sock->sk->sk_family) {
1380 case PF_UNIX:
1381 return aa_unix_bind_perm(sock, address, addrlen);
1382 case PF_INET:
1383 case PF_INET6:
1384 return aa_inet_bind_perm(sock, address, addrlen);
1385 }
1386 return aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk);
1387}
1388
1389static int apparmor_socket_connect(struct socket *sock,
1390 struct sockaddr *address, int addrlen)
1391{
1392 AA_BUG(!sock);
1393 AA_BUG(!sock->sk);
1394 AA_BUG(!address);
1395 AA_BUG(in_interrupt());
1396
1397 /* PF_UNIX goes through unix_stream_connect && unix_may_send */
1398 switch (sock->sk->sk_family) {
1399 case PF_UNIX:
1400 return 0;
1401 case PF_INET:
1402 case PF_INET6:
1403 return aa_inet_connect_perm(sock, address, addrlen);
1404 }
1405 return aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk);
1406}
1407
1408static int apparmor_socket_listen(struct socket *sock, int backlog)
1409{
1410 AA_BUG(!sock);
1411 AA_BUG(!sock->sk);
1412 AA_BUG(in_interrupt());
1413
1414 switch (sock->sk->sk_family) {
1415 case PF_UNIX:
1416 return aa_unix_listen_perm(sock, backlog);
1417 case PF_INET:
1418 case PF_INET6:
1419 return aa_inet_listen_perm(sock, backlog);
1420 }
1421 return aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk);
1422}
1423
1424/*
1425 * Note: while @newsock is created and has some information, the accept
1426 * has not been done.
1427 */
1428static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
1429{
1430 AA_BUG(!sock);
1431 AA_BUG(!sock->sk);
1432 AA_BUG(!newsock);
1433 AA_BUG(in_interrupt());
1434
1435 switch (sock->sk->sk_family) {
1436 case PF_UNIX:
1437 return aa_unix_accept_perm(sock, newsock);
1438 case PF_INET:
1439 case PF_INET6:
1440 return aa_inet_accept_perm(sock, newsock);
1441 }
1442 return aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk);
1443}
1444
1445static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
1446 struct msghdr *msg, int size)
1447{
1448 AA_BUG(!sock);
1449 AA_BUG(!sock->sk);
1450 AA_BUG(!msg);
1451 AA_BUG(in_interrupt());
1452
1453 /* PF_UNIX goes through unix_may_send */
1454 switch (sock->sk->sk_family) {
1455 case PF_UNIX:
1456 return 0;
1457 case PF_INET:
1458 case PF_INET6:
1459 return aa_inet_msg_perm(op, request, sock, msg, size);
1460 }
1461
1462 return aa_sk_perm(op, request, sock->sk);
1463}
1464
1465static int apparmor_socket_sendmsg(struct socket *sock,
1466 struct msghdr *msg, int size)
1467{
1468 int error = aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
1469
1470 if (error)
1471 return error;
1472
1473 /* TCP fast open carries connect() semantics in sendmsg(); mediate
1474 * the implicit connect so it cannot bypass the connect permission.
1475 */
1476 if ((msg->msg_flags & MSG_FASTOPEN) && msg->msg_name &&
1477 (sk_is_tcp(sock->sk) ||
1478 (sk_is_inet(sock->sk) && sock->sk->sk_type == SOCK_STREAM &&
1479 sock->sk->sk_protocol == IPPROTO_MPTCP)))
1480 error = aa_sock_msg_perm(OP_CONNECT, AA_MAY_CONNECT, sock,
1481 msg, size);
1482
1483 return error;
1484}
1485
1486static int apparmor_socket_recvmsg(struct socket *sock,
1487 struct msghdr *msg, int size, int flags)
1488{
1489 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
1490}
1491
1492/* revaliation, get/set attr, shutdown */
1493static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
1494{
1495 AA_BUG(!sock);
1496 AA_BUG(!sock->sk);
1497 AA_BUG(in_interrupt());
1498
1499 switch (sock->sk->sk_family) {
1500 case PF_UNIX:
1501 return aa_unix_sock_perm(op, request, sock);
1502 case PF_INET:
1503 case PF_INET6:
1504 return aa_inet_sock_perm(op, request, sock);
1505 }
1506 return aa_sk_perm(op, request, sock->sk);
1507}
1508
1509static int apparmor_socket_getsockname(struct socket *sock)
1510{
1511 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
1512}
1513
1514static int apparmor_socket_getpeername(struct socket *sock)
1515{
1516 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
1517}
1518
1519/* revaliation, get/set attr, opt */
1520static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
1521 int level, int optname)
1522{
1523 AA_BUG(!sock);
1524 AA_BUG(!sock->sk);
1525 AA_BUG(in_interrupt());
1526
1527 switch (sock->sk->sk_family) {
1528 case PF_UNIX:
1529 return aa_unix_opt_perm(op, request, sock, level, optname);
1530 case PF_INET:
1531 case PF_INET6:
1532 return aa_inet_opt_perm(op, request, sock, level, optname);
1533 }
1534 return aa_sk_perm(op, request, sock->sk);
1535}
1536
1537static int apparmor_socket_getsockopt(struct socket *sock, int level,
1538 int optname)
1539{
1540 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
1541 level, optname);
1542}
1543
1544static int apparmor_socket_setsockopt(struct socket *sock, int level,
1545 int optname)
1546{
1547 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1548 level, optname);
1549}
1550
1551static int apparmor_socket_shutdown(struct socket *sock, int how)
1552{
1553 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1554}
1555
1556static struct aa_label *sk_peer_get_label(struct sock *sk)
1557{
1558 struct aa_sk_ctx *ctx = aa_sock(sk);
1559
1560 if (rcu_access_pointer(ctx->peer))
1561 return aa_get_label_rcu(&ctx->peer);
1562
1563 return ERR_PTR(-ENOPROTOOPT);
1564}
1565
1566/**
1567 * apparmor_socket_getpeersec_stream - get security context of peer
1568 * @sock: socket that we are trying to get the peer context of
1569 * @optval: output - buffer to copy peer name to
1570 * @optlen: output - size of copied name in @optval
1571 * @len: size of @optval buffer
1572 * Returns: 0 on success, -errno of failure
1573 *
1574 * Note: for tcp only valid if using ipsec or cipso on lan
1575 */
1576static int apparmor_socket_getpeersec_stream(struct socket *sock,
1577 sockptr_t optval, sockptr_t optlen,
1578 unsigned int len)
1579{
1580 char *name = NULL;
1581 int slen, error = 0;
1582 struct aa_label *label;
1583 struct aa_label *peer;
1584 bool needput;
1585
1586 peer = sk_peer_get_label(sock->sk);
1587 if (IS_ERR(peer)) {
1588 error = PTR_ERR(peer);
1589 goto done;
1590 }
1591 label = begin_current_label_crit_section(&needput);
1592 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1593 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1594 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1595 /* don't include terminating \0 in slen, it breaks some apps */
1596 if (slen < 0) {
1597 error = -ENOMEM;
1598 goto done_put;
1599 }
1600 if (slen > len) {
1601 error = -ERANGE;
1602 goto done_len;
1603 }
1604
1605 if (copy_to_sockptr(optval, name, slen))
1606 error = -EFAULT;
1607done_len:
1608 if (copy_to_sockptr(optlen, &slen, sizeof(slen)))
1609 error = -EFAULT;
1610
1611done_put:
1612 end_current_label_crit_section(label, needput);
1613 aa_put_label(peer);
1614done:
1615 kfree(name);
1616 return error;
1617}
1618
1619/**
1620 * apparmor_socket_getpeersec_dgram - get security label of packet
1621 * @sock: the peer socket
1622 * @skb: packet data
1623 * @secid: pointer to where to put the secid of the packet
1624 *
1625 * Sets the netlabel socket state on sk from parent
1626 */
1627static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1628 struct sk_buff *skb, u32 *secid)
1629
1630{
1631 /* TODO: requires secid support */
1632 return -ENOPROTOOPT;
1633}
1634
1635/**
1636 * apparmor_sock_graft - Initialize newly created socket
1637 * @sk: child sock
1638 * @parent: parent socket
1639 *
1640 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1641 * just set sk security information off of current creating process label
1642 * Labeling of sk for accept case - probably should be sock based
1643 * instead of task, because of the case where an implicitly labeled
1644 * socket is shared by different tasks.
1645 */
1646static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1647{
1648 struct aa_sk_ctx *ctx = aa_sock(sk);
1649
1650 /* setup - not live */
1651 if (!rcu_access_pointer(ctx->label))
1652 rcu_assign_pointer(ctx->label, aa_get_current_label());
1653}
1654
1655#ifdef CONFIG_NETWORK_SECMARK
1656/**
1657 * apparmor_socket_sock_rcv_skb - check perms before associating skb to sk
1658 * @sk: sk to associate @skb with
1659 * @skb: skb to check for perms
1660 *
1661 * Note: can not sleep may be called with locks held
1662 *
1663 * don't want protocol specific in __skb_recv_datagram()
1664 * to deny an incoming connection socket_sock_rcv_skb()
1665 */
1666static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1667{
1668 struct aa_sk_ctx *ctx = aa_sock(sk);
1669 int error;
1670
1671 if (!skb->secmark)
1672 return 0;
1673
1674 /*
1675 * If reach here before socket_post_create hook is called, in which
1676 * case label is null, drop the packet.
1677 */
1678 if (!rcu_access_pointer(ctx->label))
1679 return -EACCES;
1680
1681 rcu_read_lock();
1682 error = apparmor_secmark_check(rcu_dereference(ctx->label), OP_RECVMSG,
1683 AA_MAY_RECEIVE, skb->secmark, sk);
1684 rcu_read_unlock();
1685
1686 return error;
1687}
1688
1689static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
1690 struct request_sock *req)
1691{
1692 struct aa_sk_ctx *ctx = aa_sock(sk);
1693 int error;
1694
1695 if (!skb->secmark)
1696 return 0;
1697
1698 rcu_read_lock();
1699 error = apparmor_secmark_check(rcu_dereference(ctx->label), OP_CONNECT,
1700 AA_MAY_CONNECT, skb->secmark, sk);
1701 rcu_read_unlock();
1702
1703 return error;
1704}
1705#endif
1706
1707#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
1708static unsigned int apparmor_ip_postroute(void *priv,
1709 struct sk_buff *skb,
1710 const struct nf_hook_state *state)
1711{
1712 struct aa_sk_ctx *ctx;
1713 struct sock *sk;
1714 int error;
1715
1716 if (!skb->secmark)
1717 return NF_ACCEPT;
1718
1719 sk = skb_to_full_sk(skb);
1720 if (sk == NULL)
1721 return NF_ACCEPT;
1722
1723 ctx = aa_sock(sk);
1724 rcu_read_lock();
1725 error = apparmor_secmark_check(rcu_dereference(ctx->label), OP_SENDMSG,
1726 AA_MAY_SEND, skb->secmark, sk);
1727 rcu_read_unlock();
1728 if (!error)
1729 return NF_ACCEPT;
1730
1731 return NF_DROP_ERR(-ECONNREFUSED);
1732}
1733
1734static const struct nf_hook_ops apparmor_nf_ops[] = {
1735 {
1736 .hook = apparmor_ip_postroute,
1737 .pf = NFPROTO_IPV4,
1738 .hooknum = NF_INET_POST_ROUTING,
1739 .priority = NF_IP_PRI_SELINUX_FIRST,
1740 },
1741#if IS_ENABLED(CONFIG_IPV6)
1742 {
1743 .hook = apparmor_ip_postroute,
1744 .pf = NFPROTO_IPV6,
1745 .hooknum = NF_INET_POST_ROUTING,
1746 .priority = NF_IP6_PRI_SELINUX_FIRST,
1747 },
1748#endif
1749};
1750#endif
1751
1752/*
1753 * The cred blob is a pointer to, not an instance of, an aa_label.
1754 */
1755struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = {
1756 .lbs_cred = sizeof(struct aa_label *),
1757 .lbs_file = sizeof(struct aa_file_ctx),
1758 .lbs_task = sizeof(struct aa_task_ctx),
1759 .lbs_sock = sizeof(struct aa_sk_ctx),
1760};
1761
1762static const struct lsm_id apparmor_lsmid = {
1763 .name = "apparmor",
1764 .id = LSM_ID_APPARMOR,
1765};
1766
1767static struct security_hook_list apparmor_hooks[] __ro_after_init = {
1768 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1769 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1770 LSM_HOOK_INIT(capget, apparmor_capget),
1771 LSM_HOOK_INIT(capable, apparmor_capable),
1772
1773 LSM_HOOK_INIT(move_mount, apparmor_move_mount),
1774 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1775 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1776 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1777
1778 LSM_HOOK_INIT(path_link, apparmor_path_link),
1779 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1780 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1781 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1782 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1783 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1784 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1785 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1786 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1787 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1788 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1789
1790 LSM_HOOK_INIT(file_open, apparmor_file_open),
1791 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1792 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1793 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1794 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1795 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1796 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1797 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1798 LSM_HOOK_INIT(file_truncate, apparmor_file_truncate),
1799
1800 LSM_HOOK_INIT(getselfattr, apparmor_getselfattr),
1801 LSM_HOOK_INIT(setselfattr, apparmor_setselfattr),
1802 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1803 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1804
1805 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1806 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1807 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1808
1809 LSM_HOOK_INIT(unix_stream_connect, apparmor_unix_stream_connect),
1810 LSM_HOOK_INIT(unix_may_send, apparmor_unix_may_send),
1811
1812 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1813 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1814 LSM_HOOK_INIT(socket_socketpair, apparmor_socket_socketpair),
1815 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1816 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1817 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1818 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1819 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1820 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1821 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1822 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1823 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1824 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1825 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1826#ifdef CONFIG_NETWORK_SECMARK
1827 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1828#endif
1829 LSM_HOOK_INIT(socket_getpeersec_stream,
1830 apparmor_socket_getpeersec_stream),
1831 LSM_HOOK_INIT(socket_getpeersec_dgram,
1832 apparmor_socket_getpeersec_dgram),
1833 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1834#ifdef CONFIG_NETWORK_SECMARK
1835 LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1836#endif
1837
1838 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1839 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1840 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1841 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1842
1843 LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
1844 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1845 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1846
1847 LSM_HOOK_INIT(task_free, apparmor_task_free),
1848 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1849 LSM_HOOK_INIT(current_getlsmprop_subj,
1850 apparmor_current_getlsmprop_subj),
1851 LSM_HOOK_INIT(task_getlsmprop_obj, apparmor_task_getlsmprop_obj),
1852 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1853 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1854 LSM_HOOK_INIT(userns_create, apparmor_userns_create),
1855
1856#ifdef CONFIG_AUDIT
1857 LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1858 LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1859 LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1860 LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1861#endif
1862
1863 LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1864 LSM_HOOK_INIT(lsmprop_to_secctx, apparmor_lsmprop_to_secctx),
1865 LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1866 LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1867
1868#ifdef CONFIG_IO_URING
1869 LSM_HOOK_INIT(uring_override_creds, apparmor_uring_override_creds),
1870 LSM_HOOK_INIT(uring_sqpoll, apparmor_uring_sqpoll),
1871#endif
1872};
1873
1874/*
1875 * AppArmor sysfs module parameters
1876 */
1877
1878static int param_set_aabool(const char *val, const struct kernel_param *kp);
1879static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1880#define param_check_aabool param_check_bool
1881static const struct kernel_param_ops param_ops_aabool = {
1882 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1883 .set = param_set_aabool,
1884 .get = param_get_aabool
1885};
1886
1887static int param_set_aauint(const char *val, const struct kernel_param *kp);
1888static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1889#define param_check_aauint param_check_uint
1890static const struct kernel_param_ops param_ops_aauint = {
1891 .set = param_set_aauint,
1892 .get = param_get_aauint
1893};
1894
1895static int param_set_aacompressionlevel(const char *val,
1896 const struct kernel_param *kp);
1897static int param_get_aacompressionlevel(char *buffer,
1898 const struct kernel_param *kp);
1899#define param_check_aacompressionlevel param_check_int
1900static const struct kernel_param_ops param_ops_aacompressionlevel = {
1901 .set = param_set_aacompressionlevel,
1902 .get = param_get_aacompressionlevel
1903};
1904
1905static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1906static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1907#define param_check_aalockpolicy param_check_bool
1908static const struct kernel_param_ops param_ops_aalockpolicy = {
1909 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1910 .set = param_set_aalockpolicy,
1911 .get = param_get_aalockpolicy
1912};
1913
1914static int param_set_debug(const char *val, const struct kernel_param *kp);
1915static int param_get_debug(char *buffer, const struct kernel_param *kp);
1916
1917static int param_set_audit(const char *val, const struct kernel_param *kp);
1918static int param_get_audit(char *buffer, const struct kernel_param *kp);
1919
1920static int param_set_mode(const char *val, const struct kernel_param *kp);
1921static int param_get_mode(char *buffer, const struct kernel_param *kp);
1922
1923/* Flag values, also controllable via /sys/module/apparmor/parameters
1924 * We define special types as we want to do additional mediation.
1925 */
1926
1927/* AppArmor global enforcement switch - complain, enforce, kill */
1928enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1929module_param_call(mode, param_set_mode, param_get_mode,
1930 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1931
1932/* whether policy verification hashing is enabled */
1933bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1934#ifdef CONFIG_SECURITY_APPARMOR_HASH
1935module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1936#endif
1937
1938/* whether policy exactly as loaded is retained for debug and checkpointing */
1939bool aa_g_export_binary = IS_ENABLED(CONFIG_SECURITY_APPARMOR_EXPORT_BINARY);
1940#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
1941module_param_named(export_binary, aa_g_export_binary, aabool, 0600);
1942#endif
1943
1944/* policy loaddata compression level */
1945int aa_g_rawdata_compression_level = AA_DEFAULT_CLEVEL;
1946module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
1947 aacompressionlevel, 0400);
1948
1949/* Debug mode */
1950int aa_g_debug;
1951module_param_call(debug, param_set_debug, param_get_debug,
1952 &aa_g_debug, 0600);
1953
1954/* Audit mode */
1955enum audit_mode aa_g_audit;
1956module_param_call(audit, param_set_audit, param_get_audit,
1957 &aa_g_audit, S_IRUSR | S_IWUSR);
1958
1959/* Determines if audit header is included in audited messages. This
1960 * provides more context if the audit daemon is not running
1961 */
1962bool aa_g_audit_header = true;
1963module_param_named(audit_header, aa_g_audit_header, aabool,
1964 S_IRUSR | S_IWUSR);
1965
1966/* lock out loading/removal of policy
1967 * TODO: add in at boot loading of policy, which is the only way to
1968 * load policy, if lock_policy is set
1969 */
1970bool aa_g_lock_policy;
1971module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1972 S_IRUSR | S_IWUSR);
1973
1974/* Syscall logging mode */
1975bool aa_g_logsyscall;
1976module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1977
1978/* Maximum pathname length before accesses will start getting rejected */
1979unsigned int aa_g_path_max = 2 * PATH_MAX;
1980module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1981
1982/* Determines how paranoid loading of policy is and how much verification
1983 * on the loaded policy is done.
1984 * DEPRECATED: read only as strict checking of load is always done now
1985 * that none root users (user namespaces) can load policy.
1986 */
1987bool aa_g_paranoid_load = IS_ENABLED(CONFIG_SECURITY_APPARMOR_PARANOID_LOAD);
1988module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1989
1990static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1991static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1992#define param_check_aaintbool param_check_int
1993static const struct kernel_param_ops param_ops_aaintbool = {
1994 .set = param_set_aaintbool,
1995 .get = param_get_aaintbool
1996};
1997/* Boot time disable flag */
1998static int apparmor_enabled __ro_after_init = 1;
1999module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
2000
2001static int __init apparmor_enabled_setup(char *str)
2002{
2003 unsigned long enabled;
2004 int error = kstrtoul(str, 0, &enabled);
2005 if (!error)
2006 apparmor_enabled = enabled ? 1 : 0;
2007 return 1;
2008}
2009
2010__setup("apparmor=", apparmor_enabled_setup);
2011
2012/* set global flag turning off the ability to load policy */
2013static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
2014{
2015 if (!apparmor_enabled)
2016 return -EINVAL;
2017 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
2018 return -EPERM;
2019 return param_set_bool(val, kp);
2020}
2021
2022static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
2023{
2024 if (!apparmor_enabled)
2025 return -EINVAL;
2026 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2027 return -EPERM;
2028 return param_get_bool(buffer, kp);
2029}
2030
2031static int param_set_aabool(const char *val, const struct kernel_param *kp)
2032{
2033 if (!apparmor_enabled)
2034 return -EINVAL;
2035 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
2036 return -EPERM;
2037 return param_set_bool(val, kp);
2038}
2039
2040static int param_get_aabool(char *buffer, const struct kernel_param *kp)
2041{
2042 if (!apparmor_enabled)
2043 return -EINVAL;
2044 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2045 return -EPERM;
2046 return param_get_bool(buffer, kp);
2047}
2048
2049static int param_set_aauint(const char *val, const struct kernel_param *kp)
2050{
2051 int error;
2052
2053 if (!apparmor_enabled)
2054 return -EINVAL;
2055 /* file is ro but enforce 2nd line check */
2056 if (apparmor_initialized)
2057 return -EPERM;
2058
2059 error = param_set_uint(val, kp);
2060 aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
2061 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
2062
2063 return error;
2064}
2065
2066static int param_get_aauint(char *buffer, const struct kernel_param *kp)
2067{
2068 if (!apparmor_enabled)
2069 return -EINVAL;
2070 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2071 return -EPERM;
2072 return param_get_uint(buffer, kp);
2073}
2074
2075/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
2076static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
2077{
2078 struct kernel_param kp_local;
2079 bool value;
2080 int error;
2081
2082 if (apparmor_initialized)
2083 return -EPERM;
2084
2085 /* Create local copy, with arg pointing to bool type. */
2086 value = !!*((int *)kp->arg);
2087 memcpy(&kp_local, kp, sizeof(kp_local));
2088 kp_local.arg = &value;
2089
2090 error = param_set_bool(val, &kp_local);
2091 if (!error)
2092 *((int *)kp->arg) = *((bool *)kp_local.arg);
2093 return error;
2094}
2095
2096/*
2097 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
2098 * 1/0, this converts the "int that is actually bool" back to bool for
2099 * display in the /sys filesystem, while keeping it "int" for the LSM
2100 * infrastructure.
2101 */
2102static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
2103{
2104 struct kernel_param kp_local;
2105 bool value;
2106
2107 /* Create local copy, with arg pointing to bool type. */
2108 value = !!*((int *)kp->arg);
2109 memcpy(&kp_local, kp, sizeof(kp_local));
2110 kp_local.arg = &value;
2111
2112 return param_get_bool(buffer, &kp_local);
2113}
2114
2115static int param_set_aacompressionlevel(const char *val,
2116 const struct kernel_param *kp)
2117{
2118 int error;
2119
2120 if (!apparmor_enabled)
2121 return -EINVAL;
2122 if (apparmor_initialized)
2123 return -EPERM;
2124
2125 error = param_set_int(val, kp);
2126
2127 aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
2128 AA_MIN_CLEVEL, AA_MAX_CLEVEL);
2129 pr_info("AppArmor: policy rawdata compression level set to %d\n",
2130 aa_g_rawdata_compression_level);
2131
2132 return error;
2133}
2134
2135static int param_get_aacompressionlevel(char *buffer,
2136 const struct kernel_param *kp)
2137{
2138 if (!apparmor_enabled)
2139 return -EINVAL;
2140 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2141 return -EPERM;
2142 return param_get_int(buffer, kp);
2143}
2144
2145static int param_get_debug(char *buffer, const struct kernel_param *kp)
2146{
2147 if (!apparmor_enabled)
2148 return -EINVAL;
2149 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2150 return -EPERM;
2151 return aa_print_debug_params(buffer);
2152}
2153
2154static int param_set_debug(const char *val, const struct kernel_param *kp)
2155{
2156 int i;
2157
2158 if (!apparmor_enabled)
2159 return -EINVAL;
2160 if (!val)
2161 return -EINVAL;
2162 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
2163 return -EPERM;
2164
2165 i = aa_parse_debug_params(val);
2166 if (i == DEBUG_PARSE_ERROR)
2167 return -EINVAL;
2168
2169 aa_g_debug = i;
2170 return 0;
2171}
2172
2173static int param_get_audit(char *buffer, const struct kernel_param *kp)
2174{
2175 if (!apparmor_enabled)
2176 return -EINVAL;
2177 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2178 return -EPERM;
2179 return sysfs_emit(buffer, "%s\n", audit_mode_names[aa_g_audit]);
2180}
2181
2182static int param_set_audit(const char *val, const struct kernel_param *kp)
2183{
2184 int i;
2185
2186 if (!apparmor_enabled)
2187 return -EINVAL;
2188 if (!val)
2189 return -EINVAL;
2190 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
2191 return -EPERM;
2192
2193 i = match_string(audit_mode_names, AUDIT_MODE_NAMES_COUNT, val);
2194 if (i < 0)
2195 return -EINVAL;
2196
2197 aa_g_audit = i;
2198 return 0;
2199}
2200
2201static int param_get_mode(char *buffer, const struct kernel_param *kp)
2202{
2203 if (!apparmor_enabled)
2204 return -EINVAL;
2205 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
2206 return -EPERM;
2207 return sysfs_emit(buffer, "%s\n", aa_profile_mode_names[aa_g_profile_mode]);
2208}
2209
2210static int param_set_mode(const char *val, const struct kernel_param *kp)
2211{
2212 int i;
2213
2214 if (!apparmor_enabled)
2215 return -EINVAL;
2216 if (!val)
2217 return -EINVAL;
2218 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
2219 return -EPERM;
2220
2221 i = match_string(aa_profile_mode_names, PROFILE_MODE_NAMES_COUNT,
2222 val);
2223 if (i < 0)
2224 return -EINVAL;
2225
2226 aa_g_profile_mode = i;
2227 return 0;
2228}
2229
2230/* arbitrary cap on how long to hold buffer because contention was
2231 * encountered before trying to put it back into the global pool
2232 */
2233#define MAX_HOLD_COUNT 64
2234
2235/* the hold count is a heuristic for lock contention, and can be
2236 * incremented async to actual buffer alloc/free. Because buffers
2237 * may be put back onto a percpu cache different than the ->hold was
2238 * added to the counts can be out of sync. Guard against underflow
2239 * and overflow
2240 */
2241static void cache_hold_inc(unsigned int *hold)
2242{
2243 if (*hold < MAX_HOLD_COUNT)
2244 (*hold)++;
2245}
2246
2247char *aa_get_buffer(bool in_atomic)
2248{
2249 union aa_buffer *aa_buf;
2250 struct aa_local_cache *cache;
2251 bool try_again = true;
2252 gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
2253
2254 /* use per cpu cached buffers first */
2255 cache = get_cpu_ptr(&aa_local_buffers);
2256 if (!list_empty(&cache->head)) {
2257 aa_buf = list_first_entry(&cache->head, union aa_buffer, list);
2258 list_del(&aa_buf->list);
2259 if (cache->hold)
2260 cache->hold--;
2261 cache->count--;
2262 put_cpu_ptr(&aa_local_buffers);
2263 return &aa_buf->buffer[0];
2264 }
2265 /* exit percpu as spinlocks may sleep on realtime kernels */
2266 put_cpu_ptr(&aa_local_buffers);
2267
2268 if (!spin_trylock(&aa_buffers_lock)) {
2269 /* had contention on lock so increase hold count. Doesn't
2270 * really matter if recorded before or after the spin lock
2271 * as there is no way to guarantee the buffer will be put
2272 * back on the same percpu cache. Instead rely on holds
2273 * roughly averaging out over time.
2274 */
2275 cache = get_cpu_ptr(&aa_local_buffers);
2276 cache_hold_inc(&cache->hold);
2277 put_cpu_ptr(&aa_local_buffers);
2278 spin_lock(&aa_buffers_lock);
2279 }
2280retry:
2281 if (buffer_count > reserve_count ||
2282 (in_atomic && !list_empty(&aa_global_buffers))) {
2283 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
2284 list);
2285 list_del(&aa_buf->list);
2286 buffer_count--;
2287 spin_unlock(&aa_buffers_lock);
2288 return aa_buf->buffer;
2289 }
2290 if (in_atomic) {
2291 /*
2292 * out of reserve buffers and in atomic context so increase
2293 * how many buffers to keep in reserve
2294 */
2295 reserve_count++;
2296 flags = GFP_ATOMIC;
2297 }
2298 spin_unlock(&aa_buffers_lock);
2299
2300 if (!in_atomic)
2301 might_sleep();
2302 aa_buf = kmalloc(aa_g_path_max, flags);
2303 if (!aa_buf) {
2304 if (try_again) {
2305 try_again = false;
2306 spin_lock(&aa_buffers_lock);
2307 goto retry;
2308 }
2309 pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
2310 return NULL;
2311 }
2312 return aa_buf->buffer;
2313}
2314
2315void aa_put_buffer(char *buf)
2316{
2317 union aa_buffer *aa_buf;
2318 struct aa_local_cache *cache;
2319
2320 if (!buf)
2321 return;
2322 aa_buf = container_of(buf, union aa_buffer, buffer[0]);
2323
2324 cache = get_cpu_ptr(&aa_local_buffers);
2325 if (!cache->hold) {
2326 put_cpu_ptr(&aa_local_buffers);
2327
2328 if (spin_trylock(&aa_buffers_lock)) {
2329 /* put back on global list */
2330 list_add(&aa_buf->list, &aa_global_buffers);
2331 buffer_count++;
2332 spin_unlock(&aa_buffers_lock);
2333 return;
2334 }
2335 /* contention on global list, fallback to percpu */
2336 cache = get_cpu_ptr(&aa_local_buffers);
2337 cache_hold_inc(&cache->hold);
2338 }
2339
2340 /* cache in percpu list */
2341 list_add(&aa_buf->list, &cache->head);
2342 cache->count++;
2343 put_cpu_ptr(&aa_local_buffers);
2344}
2345
2346/*
2347 * AppArmor init functions
2348 */
2349
2350/**
2351 * set_init_ctx - set a task context and profile on the first task.
2352 *
2353 * TODO: allow setting an alternate profile than unconfined
2354 */
2355static int __init set_init_ctx(void)
2356{
2357 struct cred *cred = (__force struct cred *)current->real_cred;
2358
2359 set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
2360
2361 return 0;
2362}
2363
2364static void destroy_buffers(void)
2365{
2366 union aa_buffer *aa_buf;
2367
2368 spin_lock(&aa_buffers_lock);
2369 while (!list_empty(&aa_global_buffers)) {
2370 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
2371 list);
2372 list_del(&aa_buf->list);
2373 spin_unlock(&aa_buffers_lock);
2374 kfree(aa_buf);
2375 spin_lock(&aa_buffers_lock);
2376 }
2377 spin_unlock(&aa_buffers_lock);
2378}
2379
2380static int __init alloc_buffers(void)
2381{
2382 union aa_buffer *aa_buf;
2383 int i, num;
2384
2385 /*
2386 * per cpu set of cached allocated buffers used to help reduce
2387 * lock contention
2388 */
2389 for_each_possible_cpu(i) {
2390 per_cpu(aa_local_buffers, i).hold = 0;
2391 per_cpu(aa_local_buffers, i).count = 0;
2392 INIT_LIST_HEAD(&per_cpu(aa_local_buffers, i).head);
2393 }
2394 /*
2395 * A function may require two buffers at once. Usually the buffers are
2396 * used for a short period of time and are shared. On UP kernel buffers
2397 * two should be enough, with more CPUs it is possible that more
2398 * buffers will be used simultaneously. The preallocated pool may grow.
2399 * This preallocation has also the side-effect that AppArmor will be
2400 * disabled early at boot if aa_g_path_max is extremely high.
2401 */
2402 if (num_online_cpus() > 1)
2403 num = 4 + RESERVE_COUNT;
2404 else
2405 num = 2 + RESERVE_COUNT;
2406
2407 for (i = 0; i < num; i++) {
2408
2409 aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
2410 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
2411 if (!aa_buf) {
2412 destroy_buffers();
2413 return -ENOMEM;
2414 }
2415 aa_put_buffer(aa_buf->buffer);
2416 }
2417 return 0;
2418}
2419
2420#ifdef CONFIG_SYSCTL
2421static int apparmor_dointvec(const struct ctl_table *table, int write,
2422 void *buffer, size_t *lenp, loff_t *ppos)
2423{
2424 if (!aa_current_policy_admin_capable(NULL))
2425 return -EPERM;
2426 if (!apparmor_enabled)
2427 return -EINVAL;
2428
2429 return proc_dointvec(table, write, buffer, lenp, ppos);
2430}
2431
2432static const struct ctl_table apparmor_sysctl_table[] = {
2433#ifdef CONFIG_USER_NS
2434 {
2435 .procname = "unprivileged_userns_apparmor_policy",
2436 .data = &unprivileged_userns_apparmor_policy,
2437 .maxlen = sizeof(int),
2438 .mode = 0600,
2439 .proc_handler = apparmor_dointvec,
2440 },
2441#endif /* CONFIG_USER_NS */
2442 {
2443 .procname = "apparmor_display_secid_mode",
2444 .data = &apparmor_display_secid_mode,
2445 .maxlen = sizeof(int),
2446 .mode = 0600,
2447 .proc_handler = apparmor_dointvec,
2448 },
2449 {
2450 .procname = "apparmor_restrict_unprivileged_unconfined",
2451 .data = &aa_unprivileged_unconfined_restricted,
2452 .maxlen = sizeof(int),
2453 .mode = 0600,
2454 .proc_handler = apparmor_dointvec,
2455 },
2456};
2457
2458static int __init apparmor_init_sysctl(void)
2459{
2460 return register_sysctl("kernel", apparmor_sysctl_table) ? 0 : -ENOMEM;
2461}
2462#else
2463static inline int apparmor_init_sysctl(void)
2464{
2465 return 0;
2466}
2467#endif /* CONFIG_SYSCTL */
2468
2469
2470#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
2471static int __net_init apparmor_nf_register(struct net *net)
2472{
2473 return nf_register_net_hooks(net, apparmor_nf_ops,
2474 ARRAY_SIZE(apparmor_nf_ops));
2475}
2476
2477static void __net_exit apparmor_nf_unregister(struct net *net)
2478{
2479 nf_unregister_net_hooks(net, apparmor_nf_ops,
2480 ARRAY_SIZE(apparmor_nf_ops));
2481}
2482
2483static struct pernet_operations apparmor_net_ops = {
2484 .init = apparmor_nf_register,
2485 .exit = apparmor_nf_unregister,
2486};
2487
2488static int __init apparmor_nf_ip_init(void)
2489{
2490 int err;
2491
2492 if (!apparmor_enabled)
2493 return 0;
2494
2495 err = register_pernet_subsys(&apparmor_net_ops);
2496 if (err)
2497 panic("Apparmor: register_pernet_subsys: error %d\n", err);
2498
2499 return 0;
2500}
2501#endif
2502
2503static const char nulldfa_src[] __aligned(8) = {
2504 #include "nulldfa.in"
2505};
2506static struct aa_dfa *nulldfa __ro_after_init;
2507
2508static char stacksplitdfa_src[] __aligned(8) = {
2509 #include "stacksplitdfa.in"
2510};
2511struct aa_dfa *stacksplitdfa __ro_after_init;
2512struct aa_policydb *nullpdb __ro_after_init;
2513
2514static int __init aa_setup_dfa_engine(void)
2515{
2516 int error = -ENOMEM;
2517
2518 nullpdb = aa_alloc_pdb(GFP_KERNEL);
2519 if (!nullpdb)
2520 return -ENOMEM;
2521
2522 nulldfa = aa_dfa_unpack(nulldfa_src, sizeof(nulldfa_src),
2523 TO_ACCEPT1_FLAG(YYTD_DATA32) |
2524 TO_ACCEPT2_FLAG(YYTD_DATA32));
2525 if (IS_ERR(nulldfa)) {
2526 error = PTR_ERR(nulldfa);
2527 nulldfa = NULL;
2528 goto fail;
2529 }
2530 nullpdb->dfa = aa_get_dfa(nulldfa);
2531 nullpdb->perms = kzalloc_objs(struct aa_perms, 2);
2532 if (!nullpdb->perms)
2533 goto fail;
2534 nullpdb->size = 2;
2535
2536 stacksplitdfa = aa_dfa_unpack(stacksplitdfa_src,
2537 sizeof(stacksplitdfa_src),
2538 TO_ACCEPT1_FLAG(YYTD_DATA32) |
2539 TO_ACCEPT2_FLAG(YYTD_DATA32));
2540 if (IS_ERR(stacksplitdfa)) {
2541 error = PTR_ERR(stacksplitdfa);
2542 goto fail;
2543 }
2544
2545 return 0;
2546
2547fail:
2548 aa_put_pdb(nullpdb);
2549 aa_put_dfa(nulldfa);
2550 nullpdb = NULL;
2551 nulldfa = NULL;
2552 stacksplitdfa = NULL;
2553
2554 return error;
2555}
2556
2557static void __init aa_teardown_dfa_engine(void)
2558{
2559 aa_put_dfa(stacksplitdfa);
2560 aa_put_dfa(nulldfa);
2561 aa_put_pdb(nullpdb);
2562 nullpdb = NULL;
2563 stacksplitdfa = NULL;
2564 nulldfa = NULL;
2565}
2566
2567static int __init apparmor_init(void)
2568{
2569 int error;
2570
2571 error = aa_setup_dfa_engine();
2572 if (error) {
2573 AA_ERROR("Unable to setup dfa engine\n");
2574 goto alloc_out;
2575 }
2576
2577 error = aa_alloc_root_ns();
2578 if (error) {
2579 AA_ERROR("Unable to allocate default profile namespace\n");
2580 goto alloc_out;
2581 }
2582
2583 error = apparmor_init_sysctl();
2584 if (error) {
2585 AA_ERROR("Unable to register sysctls\n");
2586 goto alloc_out;
2587
2588 }
2589
2590 error = alloc_buffers();
2591 if (error) {
2592 AA_ERROR("Unable to allocate work buffers\n");
2593 goto alloc_out;
2594 }
2595
2596 error = set_init_ctx();
2597 if (error) {
2598 AA_ERROR("Failed to set context on init task\n");
2599 aa_free_root_ns();
2600 goto buffers_out;
2601 }
2602 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
2603 &apparmor_lsmid);
2604
2605 /* Inform the audit system that secctx is used */
2606 audit_cfg_lsm(&apparmor_lsmid, AUDIT_CFG_LSM_SECCTX_SUBJECT);
2607
2608 /* Report that AppArmor successfully initialized */
2609 apparmor_initialized = 1;
2610 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
2611 aa_info_message("AppArmor initialized: complain mode enabled");
2612 else if (aa_g_profile_mode == APPARMOR_KILL)
2613 aa_info_message("AppArmor initialized: kill mode enabled");
2614 else
2615 aa_info_message("AppArmor initialized");
2616
2617 return error;
2618
2619buffers_out:
2620 destroy_buffers();
2621alloc_out:
2622 aa_destroy_aafs();
2623 aa_teardown_dfa_engine();
2624
2625 apparmor_enabled = false;
2626 return error;
2627}
2628
2629DEFINE_LSM(apparmor) = {
2630 .id = &apparmor_lsmid,
2631 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
2632 .enabled = &apparmor_enabled,
2633 .blobs = &apparmor_blob_sizes,
2634 .init = apparmor_init,
2635 .initcall_fs = aa_create_aafs,
2636#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
2637 .initcall_device = apparmor_nf_ip_init,
2638#endif
2639#ifdef CONFIG_SECURITY_APPARMOR_HASH
2640 .initcall_late = init_profile_hash,
2641#endif
2642};