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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/audit.h>
21#include <linux/user_namespace.h>
22#include <linux/netfilter_ipv4.h>
23#include <linux/netfilter_ipv6.h>
24#include <net/sock.h>
25#include <uapi/linux/mount.h>
26
27#include "include/apparmor.h"
28#include "include/apparmorfs.h"
29#include "include/audit.h"
30#include "include/capability.h"
31#include "include/cred.h"
32#include "include/file.h"
33#include "include/ipc.h"
34#include "include/net.h"
35#include "include/path.h"
36#include "include/label.h"
37#include "include/policy.h"
38#include "include/policy_ns.h"
39#include "include/procattr.h"
40#include "include/mount.h"
41#include "include/secid.h"
42
43/* Flag indicating whether initialization completed */
44int apparmor_initialized;
45
46DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
47
48
49/*
50 * LSM hook functions
51 */
52
53/*
54 * put the associated labels
55 */
56static void apparmor_cred_free(struct cred *cred)
57{
58 aa_put_label(cred_label(cred));
59 set_cred_label(cred, NULL);
60}
61
62/*
63 * allocate the apparmor part of blank credentials
64 */
65static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
66{
67 set_cred_label(cred, NULL);
68 return 0;
69}
70
71/*
72 * prepare new cred label for modification by prepare_cred block
73 */
74static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
75 gfp_t gfp)
76{
77 set_cred_label(new, aa_get_newest_label(cred_label(old)));
78 return 0;
79}
80
81/*
82 * transfer the apparmor data to a blank set of creds
83 */
84static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
85{
86 set_cred_label(new, aa_get_newest_label(cred_label(old)));
87}
88
89static void apparmor_task_free(struct task_struct *task)
90{
91
92 aa_free_task_ctx(task_ctx(task));
93}
94
95static int apparmor_task_alloc(struct task_struct *task,
96 unsigned long clone_flags)
97{
98 struct aa_task_ctx *new = task_ctx(task);
99
100 aa_dup_task_ctx(new, task_ctx(current));
101
102 return 0;
103}
104
105static int apparmor_ptrace_access_check(struct task_struct *child,
106 unsigned int mode)
107{
108 struct aa_label *tracer, *tracee;
109 int error;
110
111 tracer = __begin_current_label_crit_section();
112 tracee = aa_get_task_label(child);
113 error = aa_may_ptrace(tracer, tracee,
114 (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
115 : AA_PTRACE_TRACE);
116 aa_put_label(tracee);
117 __end_current_label_crit_section(tracer);
118
119 return error;
120}
121
122static int apparmor_ptrace_traceme(struct task_struct *parent)
123{
124 struct aa_label *tracer, *tracee;
125 int error;
126
127 tracee = __begin_current_label_crit_section();
128 tracer = aa_get_task_label(parent);
129 error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
130 aa_put_label(tracer);
131 __end_current_label_crit_section(tracee);
132
133 return error;
134}
135
136/* Derived from security/commoncap.c:cap_capget */
137static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
138 kernel_cap_t *inheritable, kernel_cap_t *permitted)
139{
140 struct aa_label *label;
141 const struct cred *cred;
142
143 rcu_read_lock();
144 cred = __task_cred(target);
145 label = aa_get_newest_cred_label(cred);
146
147 /*
148 * cap_capget is stacked ahead of this and will
149 * initialize effective and permitted.
150 */
151 if (!unconfined(label)) {
152 struct aa_profile *profile;
153 struct label_it i;
154
155 label_for_each_confined(i, label, profile) {
156 if (COMPLAIN_MODE(profile))
157 continue;
158 *effective = cap_intersect(*effective,
159 profile->caps.allow);
160 *permitted = cap_intersect(*permitted,
161 profile->caps.allow);
162 }
163 }
164 rcu_read_unlock();
165 aa_put_label(label);
166
167 return 0;
168}
169
170static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
171 int cap, unsigned int opts)
172{
173 struct aa_label *label;
174 int error = 0;
175
176 label = aa_get_newest_cred_label(cred);
177 if (!unconfined(label))
178 error = aa_capable(label, cap, opts);
179 aa_put_label(label);
180
181 return error;
182}
183
184/**
185 * common_perm - basic common permission check wrapper fn for paths
186 * @op: operation being checked
187 * @path: path to check permission of (NOT NULL)
188 * @mask: requested permissions mask
189 * @cond: conditional info for the permission request (NOT NULL)
190 *
191 * Returns: %0 else error code if error or permission denied
192 */
193static int common_perm(const char *op, const struct path *path, u32 mask,
194 struct path_cond *cond)
195{
196 struct aa_label *label;
197 int error = 0;
198
199 label = __begin_current_label_crit_section();
200 if (!unconfined(label))
201 error = aa_path_perm(op, label, path, 0, mask, cond);
202 __end_current_label_crit_section(label);
203
204 return error;
205}
206
207/**
208 * common_perm_cond - common permission wrapper around inode cond
209 * @op: operation being checked
210 * @path: location to check (NOT NULL)
211 * @mask: requested permissions mask
212 *
213 * Returns: %0 else error code if error or permission denied
214 */
215static int common_perm_cond(const char *op, const struct path *path, u32 mask)
216{
217 struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
218 d_backing_inode(path->dentry)->i_mode
219 };
220
221 if (!path_mediated_fs(path->dentry))
222 return 0;
223
224 return common_perm(op, path, mask, &cond);
225}
226
227/**
228 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
229 * @op: operation being checked
230 * @dir: directory of the dentry (NOT NULL)
231 * @dentry: dentry to check (NOT NULL)
232 * @mask: requested permissions mask
233 * @cond: conditional info for the permission request (NOT NULL)
234 *
235 * Returns: %0 else error code if error or permission denied
236 */
237static int common_perm_dir_dentry(const char *op, const struct path *dir,
238 struct dentry *dentry, u32 mask,
239 struct path_cond *cond)
240{
241 struct path path = { .mnt = dir->mnt, .dentry = dentry };
242
243 return common_perm(op, &path, mask, cond);
244}
245
246/**
247 * common_perm_rm - common permission wrapper for operations doing rm
248 * @op: operation being checked
249 * @dir: directory that the dentry is in (NOT NULL)
250 * @dentry: dentry being rm'd (NOT NULL)
251 * @mask: requested permission mask
252 *
253 * Returns: %0 else error code if error or permission denied
254 */
255static int common_perm_rm(const char *op, const struct path *dir,
256 struct dentry *dentry, u32 mask)
257{
258 struct inode *inode = d_backing_inode(dentry);
259 struct path_cond cond = { };
260
261 if (!inode || !path_mediated_fs(dentry))
262 return 0;
263
264 cond.uid = inode->i_uid;
265 cond.mode = inode->i_mode;
266
267 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
268}
269
270/**
271 * common_perm_create - common permission wrapper for operations doing create
272 * @op: operation being checked
273 * @dir: directory that dentry will be created in (NOT NULL)
274 * @dentry: dentry to create (NOT NULL)
275 * @mask: request permission mask
276 * @mode: created file mode
277 *
278 * Returns: %0 else error code if error or permission denied
279 */
280static int common_perm_create(const char *op, const struct path *dir,
281 struct dentry *dentry, u32 mask, umode_t mode)
282{
283 struct path_cond cond = { current_fsuid(), mode };
284
285 if (!path_mediated_fs(dir->dentry))
286 return 0;
287
288 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
289}
290
291static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
292{
293 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
294}
295
296static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
297 umode_t mode)
298{
299 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
300 S_IFDIR);
301}
302
303static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
304{
305 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
306}
307
308static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
309 umode_t mode, unsigned int dev)
310{
311 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
312}
313
314static int apparmor_path_truncate(const struct path *path)
315{
316 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
317}
318
319static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
320 const char *old_name)
321{
322 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
323 S_IFLNK);
324}
325
326static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
327 struct dentry *new_dentry)
328{
329 struct aa_label *label;
330 int error = 0;
331
332 if (!path_mediated_fs(old_dentry))
333 return 0;
334
335 label = begin_current_label_crit_section();
336 if (!unconfined(label))
337 error = aa_path_link(label, old_dentry, new_dir, new_dentry);
338 end_current_label_crit_section(label);
339
340 return error;
341}
342
343static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
344 const struct path *new_dir, struct dentry *new_dentry)
345{
346 struct aa_label *label;
347 int error = 0;
348
349 if (!path_mediated_fs(old_dentry))
350 return 0;
351
352 label = begin_current_label_crit_section();
353 if (!unconfined(label)) {
354 struct path old_path = { .mnt = old_dir->mnt,
355 .dentry = old_dentry };
356 struct path new_path = { .mnt = new_dir->mnt,
357 .dentry = new_dentry };
358 struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
359 d_backing_inode(old_dentry)->i_mode
360 };
361
362 error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
363 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
364 AA_MAY_SETATTR | AA_MAY_DELETE,
365 &cond);
366 if (!error)
367 error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
368 0, MAY_WRITE | AA_MAY_SETATTR |
369 AA_MAY_CREATE, &cond);
370
371 }
372 end_current_label_crit_section(label);
373
374 return error;
375}
376
377static int apparmor_path_chmod(const struct path *path, umode_t mode)
378{
379 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
380}
381
382static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
383{
384 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
385}
386
387static int apparmor_inode_getattr(const struct path *path)
388{
389 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
390}
391
392static int apparmor_file_open(struct file *file)
393{
394 struct aa_file_ctx *fctx = file_ctx(file);
395 struct aa_label *label;
396 int error = 0;
397
398 if (!path_mediated_fs(file->f_path.dentry))
399 return 0;
400
401 /* If in exec, permission is handled by bprm hooks.
402 * Cache permissions granted by the previous exec check, with
403 * implicit read and executable mmap which are required to
404 * actually execute the image.
405 */
406 if (current->in_execve) {
407 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
408 return 0;
409 }
410
411 label = aa_get_newest_cred_label(file->f_cred);
412 if (!unconfined(label)) {
413 struct inode *inode = file_inode(file);
414 struct path_cond cond = { inode->i_uid, inode->i_mode };
415
416 error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
417 aa_map_file_to_perms(file), &cond);
418 /* todo cache full allowed permissions set and state */
419 fctx->allow = aa_map_file_to_perms(file);
420 }
421 aa_put_label(label);
422
423 return error;
424}
425
426static int apparmor_file_alloc_security(struct file *file)
427{
428 struct aa_file_ctx *ctx = file_ctx(file);
429 struct aa_label *label = begin_current_label_crit_section();
430
431 spin_lock_init(&ctx->lock);
432 rcu_assign_pointer(ctx->label, aa_get_label(label));
433 end_current_label_crit_section(label);
434 return 0;
435}
436
437static void apparmor_file_free_security(struct file *file)
438{
439 struct aa_file_ctx *ctx = file_ctx(file);
440
441 if (ctx)
442 aa_put_label(rcu_access_pointer(ctx->label));
443}
444
445static int common_file_perm(const char *op, struct file *file, u32 mask)
446{
447 struct aa_label *label;
448 int error = 0;
449
450 /* don't reaudit files closed during inheritance */
451 if (file->f_path.dentry == aa_null.dentry)
452 return -EACCES;
453
454 label = __begin_current_label_crit_section();
455 error = aa_file_perm(op, label, file, mask);
456 __end_current_label_crit_section(label);
457
458 return error;
459}
460
461static int apparmor_file_receive(struct file *file)
462{
463 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
464}
465
466static int apparmor_file_permission(struct file *file, int mask)
467{
468 return common_file_perm(OP_FPERM, file, mask);
469}
470
471static int apparmor_file_lock(struct file *file, unsigned int cmd)
472{
473 u32 mask = AA_MAY_LOCK;
474
475 if (cmd == F_WRLCK)
476 mask |= MAY_WRITE;
477
478 return common_file_perm(OP_FLOCK, file, mask);
479}
480
481static int common_mmap(const char *op, struct file *file, unsigned long prot,
482 unsigned long flags)
483{
484 int mask = 0;
485
486 if (!file || !file_ctx(file))
487 return 0;
488
489 if (prot & PROT_READ)
490 mask |= MAY_READ;
491 /*
492 * Private mappings don't require write perms since they don't
493 * write back to the files
494 */
495 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
496 mask |= MAY_WRITE;
497 if (prot & PROT_EXEC)
498 mask |= AA_EXEC_MMAP;
499
500 return common_file_perm(op, file, mask);
501}
502
503static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
504 unsigned long prot, unsigned long flags)
505{
506 return common_mmap(OP_FMMAP, file, prot, flags);
507}
508
509static int apparmor_file_mprotect(struct vm_area_struct *vma,
510 unsigned long reqprot, unsigned long prot)
511{
512 return common_mmap(OP_FMPROT, vma->vm_file, prot,
513 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
514}
515
516static int apparmor_sb_mount(const char *dev_name, const struct path *path,
517 const char *type, unsigned long flags, void *data)
518{
519 struct aa_label *label;
520 int error = 0;
521
522 /* Discard magic */
523 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
524 flags &= ~MS_MGC_MSK;
525
526 flags &= ~AA_MS_IGNORE_MASK;
527
528 label = __begin_current_label_crit_section();
529 if (!unconfined(label)) {
530 if (flags & MS_REMOUNT)
531 error = aa_remount(label, path, flags, data);
532 else if (flags & MS_BIND)
533 error = aa_bind_mount(label, path, dev_name, flags);
534 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
535 MS_UNBINDABLE))
536 error = aa_mount_change_type(label, path, flags);
537 else if (flags & MS_MOVE)
538 error = aa_move_mount(label, path, dev_name);
539 else
540 error = aa_new_mount(label, dev_name, path, type,
541 flags, data);
542 }
543 __end_current_label_crit_section(label);
544
545 return error;
546}
547
548static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
549{
550 struct aa_label *label;
551 int error = 0;
552
553 label = __begin_current_label_crit_section();
554 if (!unconfined(label))
555 error = aa_umount(label, mnt, flags);
556 __end_current_label_crit_section(label);
557
558 return error;
559}
560
561static int apparmor_sb_pivotroot(const struct path *old_path,
562 const struct path *new_path)
563{
564 struct aa_label *label;
565 int error = 0;
566
567 label = aa_get_current_label();
568 if (!unconfined(label))
569 error = aa_pivotroot(label, old_path, new_path);
570 aa_put_label(label);
571
572 return error;
573}
574
575static int apparmor_getprocattr(struct task_struct *task, char *name,
576 char **value)
577{
578 int error = -ENOENT;
579 /* released below */
580 const struct cred *cred = get_task_cred(task);
581 struct aa_task_ctx *ctx = task_ctx(current);
582 struct aa_label *label = NULL;
583
584 if (strcmp(name, "current") == 0)
585 label = aa_get_newest_label(cred_label(cred));
586 else if (strcmp(name, "prev") == 0 && ctx->previous)
587 label = aa_get_newest_label(ctx->previous);
588 else if (strcmp(name, "exec") == 0 && ctx->onexec)
589 label = aa_get_newest_label(ctx->onexec);
590 else
591 error = -EINVAL;
592
593 if (label)
594 error = aa_getprocattr(label, value);
595
596 aa_put_label(label);
597 put_cred(cred);
598
599 return error;
600}
601
602static int apparmor_setprocattr(const char *name, void *value,
603 size_t size)
604{
605 char *command, *largs = NULL, *args = value;
606 size_t arg_size;
607 int error;
608 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
609
610 if (size == 0)
611 return -EINVAL;
612
613 /* AppArmor requires that the buffer must be null terminated atm */
614 if (args[size - 1] != '\0') {
615 /* null terminate */
616 largs = args = kmalloc(size + 1, GFP_KERNEL);
617 if (!args)
618 return -ENOMEM;
619 memcpy(args, value, size);
620 args[size] = '\0';
621 }
622
623 error = -EINVAL;
624 args = strim(args);
625 command = strsep(&args, " ");
626 if (!args)
627 goto out;
628 args = skip_spaces(args);
629 if (!*args)
630 goto out;
631
632 arg_size = size - (args - (largs ? largs : (char *) value));
633 if (strcmp(name, "current") == 0) {
634 if (strcmp(command, "changehat") == 0) {
635 error = aa_setprocattr_changehat(args, arg_size,
636 AA_CHANGE_NOFLAGS);
637 } else if (strcmp(command, "permhat") == 0) {
638 error = aa_setprocattr_changehat(args, arg_size,
639 AA_CHANGE_TEST);
640 } else if (strcmp(command, "changeprofile") == 0) {
641 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
642 } else if (strcmp(command, "permprofile") == 0) {
643 error = aa_change_profile(args, AA_CHANGE_TEST);
644 } else if (strcmp(command, "stack") == 0) {
645 error = aa_change_profile(args, AA_CHANGE_STACK);
646 } else
647 goto fail;
648 } else if (strcmp(name, "exec") == 0) {
649 if (strcmp(command, "exec") == 0)
650 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
651 else if (strcmp(command, "stack") == 0)
652 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
653 AA_CHANGE_STACK));
654 else
655 goto fail;
656 } else
657 /* only support the "current" and "exec" process attributes */
658 goto fail;
659
660 if (!error)
661 error = size;
662out:
663 kfree(largs);
664 return error;
665
666fail:
667 aad(&sa)->label = begin_current_label_crit_section();
668 aad(&sa)->info = name;
669 aad(&sa)->error = error = -EINVAL;
670 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
671 end_current_label_crit_section(aad(&sa)->label);
672 goto out;
673}
674
675/**
676 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
677 * @bprm: binprm for the exec (NOT NULL)
678 */
679static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
680{
681 struct aa_label *label = aa_current_raw_label();
682 struct aa_label *new_label = cred_label(bprm->cred);
683
684 /* bail out if unconfined or not changing profile */
685 if ((new_label->proxy == label->proxy) ||
686 (unconfined(new_label)))
687 return;
688
689 aa_inherit_files(bprm->cred, current->files);
690
691 current->pdeath_signal = 0;
692
693 /* reset soft limits and set hard limits for the new label */
694 __aa_transition_rlimits(label, new_label);
695}
696
697/**
698 * apparmor_bprm_committed_cred - do cleanup after new creds committed
699 * @bprm: binprm for the exec (NOT NULL)
700 */
701static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
702{
703 /* clear out temporary/transitional state from the context */
704 aa_clear_task_ctx_trans(task_ctx(current));
705
706 return;
707}
708
709static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
710{
711 struct aa_label *label = aa_get_task_label(p);
712 *secid = label->secid;
713 aa_put_label(label);
714}
715
716static int apparmor_task_setrlimit(struct task_struct *task,
717 unsigned int resource, struct rlimit *new_rlim)
718{
719 struct aa_label *label = __begin_current_label_crit_section();
720 int error = 0;
721
722 if (!unconfined(label))
723 error = aa_task_setrlimit(label, task, resource, new_rlim);
724 __end_current_label_crit_section(label);
725
726 return error;
727}
728
729static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
730 int sig, const struct cred *cred)
731{
732 struct aa_label *cl, *tl;
733 int error;
734
735 if (cred) {
736 /*
737 * Dealing with USB IO specific behavior
738 */
739 cl = aa_get_newest_cred_label(cred);
740 tl = aa_get_task_label(target);
741 error = aa_may_signal(cl, tl, sig);
742 aa_put_label(cl);
743 aa_put_label(tl);
744 return error;
745 }
746
747 cl = __begin_current_label_crit_section();
748 tl = aa_get_task_label(target);
749 error = aa_may_signal(cl, tl, sig);
750 aa_put_label(tl);
751 __end_current_label_crit_section(cl);
752
753 return error;
754}
755
756/**
757 * apparmor_sk_alloc_security - allocate and attach the sk_security field
758 */
759static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
760{
761 struct aa_sk_ctx *ctx;
762
763 ctx = kzalloc(sizeof(*ctx), flags);
764 if (!ctx)
765 return -ENOMEM;
766
767 SK_CTX(sk) = ctx;
768
769 return 0;
770}
771
772/**
773 * apparmor_sk_free_security - free the sk_security field
774 */
775static void apparmor_sk_free_security(struct sock *sk)
776{
777 struct aa_sk_ctx *ctx = SK_CTX(sk);
778
779 SK_CTX(sk) = NULL;
780 aa_put_label(ctx->label);
781 aa_put_label(ctx->peer);
782 kfree(ctx);
783}
784
785/**
786 * apparmor_clone_security - clone the sk_security field
787 */
788static void apparmor_sk_clone_security(const struct sock *sk,
789 struct sock *newsk)
790{
791 struct aa_sk_ctx *ctx = SK_CTX(sk);
792 struct aa_sk_ctx *new = SK_CTX(newsk);
793
794 new->label = aa_get_label(ctx->label);
795 new->peer = aa_get_label(ctx->peer);
796}
797
798/**
799 * apparmor_socket_create - check perms before creating a new socket
800 */
801static int apparmor_socket_create(int family, int type, int protocol, int kern)
802{
803 struct aa_label *label;
804 int error = 0;
805
806 AA_BUG(in_interrupt());
807
808 label = begin_current_label_crit_section();
809 if (!(kern || unconfined(label)))
810 error = af_select(family,
811 create_perm(label, family, type, protocol),
812 aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
813 family, type, protocol));
814 end_current_label_crit_section(label);
815
816 return error;
817}
818
819/**
820 * apparmor_socket_post_create - setup the per-socket security struct
821 *
822 * Note:
823 * - kernel sockets currently labeled unconfined but we may want to
824 * move to a special kernel label
825 * - socket may not have sk here if created with sock_create_lite or
826 * sock_alloc. These should be accept cases which will be handled in
827 * sock_graft.
828 */
829static int apparmor_socket_post_create(struct socket *sock, int family,
830 int type, int protocol, int kern)
831{
832 struct aa_label *label;
833
834 if (kern) {
835 struct aa_ns *ns = aa_get_current_ns();
836
837 label = aa_get_label(ns_unconfined(ns));
838 aa_put_ns(ns);
839 } else
840 label = aa_get_current_label();
841
842 if (sock->sk) {
843 struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
844
845 aa_put_label(ctx->label);
846 ctx->label = aa_get_label(label);
847 }
848 aa_put_label(label);
849
850 return 0;
851}
852
853/**
854 * apparmor_socket_bind - check perms before bind addr to socket
855 */
856static int apparmor_socket_bind(struct socket *sock,
857 struct sockaddr *address, int addrlen)
858{
859 AA_BUG(!sock);
860 AA_BUG(!sock->sk);
861 AA_BUG(!address);
862 AA_BUG(in_interrupt());
863
864 return af_select(sock->sk->sk_family,
865 bind_perm(sock, address, addrlen),
866 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
867}
868
869/**
870 * apparmor_socket_connect - check perms before connecting @sock to @address
871 */
872static int apparmor_socket_connect(struct socket *sock,
873 struct sockaddr *address, int addrlen)
874{
875 AA_BUG(!sock);
876 AA_BUG(!sock->sk);
877 AA_BUG(!address);
878 AA_BUG(in_interrupt());
879
880 return af_select(sock->sk->sk_family,
881 connect_perm(sock, address, addrlen),
882 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
883}
884
885/**
886 * apparmor_socket_list - check perms before allowing listen
887 */
888static int apparmor_socket_listen(struct socket *sock, int backlog)
889{
890 AA_BUG(!sock);
891 AA_BUG(!sock->sk);
892 AA_BUG(in_interrupt());
893
894 return af_select(sock->sk->sk_family,
895 listen_perm(sock, backlog),
896 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
897}
898
899/**
900 * apparmor_socket_accept - check perms before accepting a new connection.
901 *
902 * Note: while @newsock is created and has some information, the accept
903 * has not been done.
904 */
905static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
906{
907 AA_BUG(!sock);
908 AA_BUG(!sock->sk);
909 AA_BUG(!newsock);
910 AA_BUG(in_interrupt());
911
912 return af_select(sock->sk->sk_family,
913 accept_perm(sock, newsock),
914 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
915}
916
917static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
918 struct msghdr *msg, int size)
919{
920 AA_BUG(!sock);
921 AA_BUG(!sock->sk);
922 AA_BUG(!msg);
923 AA_BUG(in_interrupt());
924
925 return af_select(sock->sk->sk_family,
926 msg_perm(op, request, sock, msg, size),
927 aa_sk_perm(op, request, sock->sk));
928}
929
930/**
931 * apparmor_socket_sendmsg - check perms before sending msg to another socket
932 */
933static int apparmor_socket_sendmsg(struct socket *sock,
934 struct msghdr *msg, int size)
935{
936 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
937}
938
939/**
940 * apparmor_socket_recvmsg - check perms before receiving a message
941 */
942static int apparmor_socket_recvmsg(struct socket *sock,
943 struct msghdr *msg, int size, int flags)
944{
945 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
946}
947
948/* revaliation, get/set attr, shutdown */
949static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
950{
951 AA_BUG(!sock);
952 AA_BUG(!sock->sk);
953 AA_BUG(in_interrupt());
954
955 return af_select(sock->sk->sk_family,
956 sock_perm(op, request, sock),
957 aa_sk_perm(op, request, sock->sk));
958}
959
960/**
961 * apparmor_socket_getsockname - check perms before getting the local address
962 */
963static int apparmor_socket_getsockname(struct socket *sock)
964{
965 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
966}
967
968/**
969 * apparmor_socket_getpeername - check perms before getting remote address
970 */
971static int apparmor_socket_getpeername(struct socket *sock)
972{
973 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
974}
975
976/* revaliation, get/set attr, opt */
977static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
978 int level, int optname)
979{
980 AA_BUG(!sock);
981 AA_BUG(!sock->sk);
982 AA_BUG(in_interrupt());
983
984 return af_select(sock->sk->sk_family,
985 opt_perm(op, request, sock, level, optname),
986 aa_sk_perm(op, request, sock->sk));
987}
988
989/**
990 * apparmor_getsockopt - check perms before getting socket options
991 */
992static int apparmor_socket_getsockopt(struct socket *sock, int level,
993 int optname)
994{
995 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
996 level, optname);
997}
998
999/**
1000 * apparmor_setsockopt - check perms before setting socket options
1001 */
1002static int apparmor_socket_setsockopt(struct socket *sock, int level,
1003 int optname)
1004{
1005 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1006 level, optname);
1007}
1008
1009/**
1010 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1011 */
1012static int apparmor_socket_shutdown(struct socket *sock, int how)
1013{
1014 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1015}
1016
1017#ifdef CONFIG_NETWORK_SECMARK
1018/**
1019 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1020 *
1021 * Note: can not sleep may be called with locks held
1022 *
1023 * dont want protocol specific in __skb_recv_datagram()
1024 * to deny an incoming connection socket_sock_rcv_skb()
1025 */
1026static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1027{
1028 struct aa_sk_ctx *ctx = SK_CTX(sk);
1029
1030 if (!skb->secmark)
1031 return 0;
1032
1033 return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1034 skb->secmark, sk);
1035}
1036#endif
1037
1038
1039static struct aa_label *sk_peer_label(struct sock *sk)
1040{
1041 struct aa_sk_ctx *ctx = SK_CTX(sk);
1042
1043 if (ctx->peer)
1044 return ctx->peer;
1045
1046 return ERR_PTR(-ENOPROTOOPT);
1047}
1048
1049/**
1050 * apparmor_socket_getpeersec_stream - get security context of peer
1051 *
1052 * Note: for tcp only valid if using ipsec or cipso on lan
1053 */
1054static int apparmor_socket_getpeersec_stream(struct socket *sock,
1055 char __user *optval,
1056 int __user *optlen,
1057 unsigned int len)
1058{
1059 char *name;
1060 int slen, error = 0;
1061 struct aa_label *label;
1062 struct aa_label *peer;
1063
1064 label = begin_current_label_crit_section();
1065 peer = sk_peer_label(sock->sk);
1066 if (IS_ERR(peer)) {
1067 error = PTR_ERR(peer);
1068 goto done;
1069 }
1070 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1071 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1072 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1073 /* don't include terminating \0 in slen, it breaks some apps */
1074 if (slen < 0) {
1075 error = -ENOMEM;
1076 } else {
1077 if (slen > len) {
1078 error = -ERANGE;
1079 } else if (copy_to_user(optval, name, slen)) {
1080 error = -EFAULT;
1081 goto out;
1082 }
1083 if (put_user(slen, optlen))
1084 error = -EFAULT;
1085out:
1086 kfree(name);
1087
1088 }
1089
1090done:
1091 end_current_label_crit_section(label);
1092
1093 return error;
1094}
1095
1096/**
1097 * apparmor_socket_getpeersec_dgram - get security label of packet
1098 * @sock: the peer socket
1099 * @skb: packet data
1100 * @secid: pointer to where to put the secid of the packet
1101 *
1102 * Sets the netlabel socket state on sk from parent
1103 */
1104static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1105 struct sk_buff *skb, u32 *secid)
1106
1107{
1108 /* TODO: requires secid support */
1109 return -ENOPROTOOPT;
1110}
1111
1112/**
1113 * apparmor_sock_graft - Initialize newly created socket
1114 * @sk: child sock
1115 * @parent: parent socket
1116 *
1117 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1118 * just set sk security information off of current creating process label
1119 * Labeling of sk for accept case - probably should be sock based
1120 * instead of task, because of the case where an implicitly labeled
1121 * socket is shared by different tasks.
1122 */
1123static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1124{
1125 struct aa_sk_ctx *ctx = SK_CTX(sk);
1126
1127 if (!ctx->label)
1128 ctx->label = aa_get_current_label();
1129}
1130
1131#ifdef CONFIG_NETWORK_SECMARK
1132static int apparmor_inet_conn_request(struct sock *sk, struct sk_buff *skb,
1133 struct request_sock *req)
1134{
1135 struct aa_sk_ctx *ctx = SK_CTX(sk);
1136
1137 if (!skb->secmark)
1138 return 0;
1139
1140 return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1141 skb->secmark, sk);
1142}
1143#endif
1144
1145/*
1146 * The cred blob is a pointer to, not an instance of, an aa_task_ctx.
1147 */
1148struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
1149 .lbs_cred = sizeof(struct aa_task_ctx *),
1150 .lbs_file = sizeof(struct aa_file_ctx),
1151 .lbs_task = sizeof(struct aa_task_ctx),
1152};
1153
1154static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1155 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1156 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1157 LSM_HOOK_INIT(capget, apparmor_capget),
1158 LSM_HOOK_INIT(capable, apparmor_capable),
1159
1160 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1161 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1162 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1163
1164 LSM_HOOK_INIT(path_link, apparmor_path_link),
1165 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1166 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1167 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1168 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1169 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1170 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1171 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1172 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1173 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1174 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1175
1176 LSM_HOOK_INIT(file_open, apparmor_file_open),
1177 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1178 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1179 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1180 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1181 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1182 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1183 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1184
1185 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1186 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1187
1188 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1189 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1190 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1191
1192 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1193 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1194 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1195 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1196 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1197 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1198 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1199 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1200 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1201 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1202 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1203 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1204 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1205#ifdef CONFIG_NETWORK_SECMARK
1206 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1207#endif
1208 LSM_HOOK_INIT(socket_getpeersec_stream,
1209 apparmor_socket_getpeersec_stream),
1210 LSM_HOOK_INIT(socket_getpeersec_dgram,
1211 apparmor_socket_getpeersec_dgram),
1212 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1213#ifdef CONFIG_NETWORK_SECMARK
1214 LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1215#endif
1216
1217 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1218 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1219 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1220 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1221
1222 LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
1223 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1224 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1225
1226 LSM_HOOK_INIT(task_free, apparmor_task_free),
1227 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1228 LSM_HOOK_INIT(task_getsecid, apparmor_task_getsecid),
1229 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1230 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1231
1232#ifdef CONFIG_AUDIT
1233 LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1234 LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1235 LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1236 LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1237#endif
1238
1239 LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1240 LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1241 LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1242};
1243
1244/*
1245 * AppArmor sysfs module parameters
1246 */
1247
1248static int param_set_aabool(const char *val, const struct kernel_param *kp);
1249static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1250#define param_check_aabool param_check_bool
1251static const struct kernel_param_ops param_ops_aabool = {
1252 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1253 .set = param_set_aabool,
1254 .get = param_get_aabool
1255};
1256
1257static int param_set_aauint(const char *val, const struct kernel_param *kp);
1258static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1259#define param_check_aauint param_check_uint
1260static const struct kernel_param_ops param_ops_aauint = {
1261 .set = param_set_aauint,
1262 .get = param_get_aauint
1263};
1264
1265static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1266static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1267#define param_check_aalockpolicy param_check_bool
1268static const struct kernel_param_ops param_ops_aalockpolicy = {
1269 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1270 .set = param_set_aalockpolicy,
1271 .get = param_get_aalockpolicy
1272};
1273
1274static int param_set_audit(const char *val, const struct kernel_param *kp);
1275static int param_get_audit(char *buffer, const struct kernel_param *kp);
1276
1277static int param_set_mode(const char *val, const struct kernel_param *kp);
1278static int param_get_mode(char *buffer, const struct kernel_param *kp);
1279
1280/* Flag values, also controllable via /sys/module/apparmor/parameters
1281 * We define special types as we want to do additional mediation.
1282 */
1283
1284/* AppArmor global enforcement switch - complain, enforce, kill */
1285enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1286module_param_call(mode, param_set_mode, param_get_mode,
1287 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1288
1289/* whether policy verification hashing is enabled */
1290bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1291#ifdef CONFIG_SECURITY_APPARMOR_HASH
1292module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1293#endif
1294
1295/* Debug mode */
1296bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1297module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1298
1299/* Audit mode */
1300enum audit_mode aa_g_audit;
1301module_param_call(audit, param_set_audit, param_get_audit,
1302 &aa_g_audit, S_IRUSR | S_IWUSR);
1303
1304/* Determines if audit header is included in audited messages. This
1305 * provides more context if the audit daemon is not running
1306 */
1307bool aa_g_audit_header = true;
1308module_param_named(audit_header, aa_g_audit_header, aabool,
1309 S_IRUSR | S_IWUSR);
1310
1311/* lock out loading/removal of policy
1312 * TODO: add in at boot loading of policy, which is the only way to
1313 * load policy, if lock_policy is set
1314 */
1315bool aa_g_lock_policy;
1316module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1317 S_IRUSR | S_IWUSR);
1318
1319/* Syscall logging mode */
1320bool aa_g_logsyscall;
1321module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1322
1323/* Maximum pathname length before accesses will start getting rejected */
1324unsigned int aa_g_path_max = 2 * PATH_MAX;
1325module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1326
1327/* Determines how paranoid loading of policy is and how much verification
1328 * on the loaded policy is done.
1329 * DEPRECATED: read only as strict checking of load is always done now
1330 * that none root users (user namespaces) can load policy.
1331 */
1332bool aa_g_paranoid_load = true;
1333module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1334
1335static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1336static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1337#define param_check_aaintbool param_check_int
1338static const struct kernel_param_ops param_ops_aaintbool = {
1339 .set = param_set_aaintbool,
1340 .get = param_get_aaintbool
1341};
1342/* Boot time disable flag */
1343static int apparmor_enabled __lsm_ro_after_init = 1;
1344module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1345
1346static int __init apparmor_enabled_setup(char *str)
1347{
1348 unsigned long enabled;
1349 int error = kstrtoul(str, 0, &enabled);
1350 if (!error)
1351 apparmor_enabled = enabled ? 1 : 0;
1352 return 1;
1353}
1354
1355__setup("apparmor=", apparmor_enabled_setup);
1356
1357/* set global flag turning off the ability to load policy */
1358static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1359{
1360 if (!apparmor_enabled)
1361 return -EINVAL;
1362 if (apparmor_initialized && !policy_admin_capable(NULL))
1363 return -EPERM;
1364 return param_set_bool(val, kp);
1365}
1366
1367static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1368{
1369 if (!apparmor_enabled)
1370 return -EINVAL;
1371 if (apparmor_initialized && !policy_view_capable(NULL))
1372 return -EPERM;
1373 return param_get_bool(buffer, kp);
1374}
1375
1376static int param_set_aabool(const char *val, const struct kernel_param *kp)
1377{
1378 if (!apparmor_enabled)
1379 return -EINVAL;
1380 if (apparmor_initialized && !policy_admin_capable(NULL))
1381 return -EPERM;
1382 return param_set_bool(val, kp);
1383}
1384
1385static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1386{
1387 if (!apparmor_enabled)
1388 return -EINVAL;
1389 if (apparmor_initialized && !policy_view_capable(NULL))
1390 return -EPERM;
1391 return param_get_bool(buffer, kp);
1392}
1393
1394static int param_set_aauint(const char *val, const struct kernel_param *kp)
1395{
1396 int error;
1397
1398 if (!apparmor_enabled)
1399 return -EINVAL;
1400 /* file is ro but enforce 2nd line check */
1401 if (apparmor_initialized)
1402 return -EPERM;
1403
1404 error = param_set_uint(val, kp);
1405 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1406
1407 return error;
1408}
1409
1410static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1411{
1412 if (!apparmor_enabled)
1413 return -EINVAL;
1414 if (apparmor_initialized && !policy_view_capable(NULL))
1415 return -EPERM;
1416 return param_get_uint(buffer, kp);
1417}
1418
1419/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1420static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1421{
1422 struct kernel_param kp_local;
1423 bool value;
1424 int error;
1425
1426 if (apparmor_initialized)
1427 return -EPERM;
1428
1429 /* Create local copy, with arg pointing to bool type. */
1430 value = !!*((int *)kp->arg);
1431 memcpy(&kp_local, kp, sizeof(kp_local));
1432 kp_local.arg = &value;
1433
1434 error = param_set_bool(val, &kp_local);
1435 if (!error)
1436 *((int *)kp->arg) = *((bool *)kp_local.arg);
1437 return error;
1438}
1439
1440/*
1441 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1442 * 1/0, this converts the "int that is actually bool" back to bool for
1443 * display in the /sys filesystem, while keeping it "int" for the LSM
1444 * infrastructure.
1445 */
1446static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1447{
1448 struct kernel_param kp_local;
1449 bool value;
1450
1451 /* Create local copy, with arg pointing to bool type. */
1452 value = !!*((int *)kp->arg);
1453 memcpy(&kp_local, kp, sizeof(kp_local));
1454 kp_local.arg = &value;
1455
1456 return param_get_bool(buffer, &kp_local);
1457}
1458
1459static int param_get_audit(char *buffer, const struct kernel_param *kp)
1460{
1461 if (!apparmor_enabled)
1462 return -EINVAL;
1463 if (apparmor_initialized && !policy_view_capable(NULL))
1464 return -EPERM;
1465 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1466}
1467
1468static int param_set_audit(const char *val, const struct kernel_param *kp)
1469{
1470 int i;
1471
1472 if (!apparmor_enabled)
1473 return -EINVAL;
1474 if (!val)
1475 return -EINVAL;
1476 if (apparmor_initialized && !policy_admin_capable(NULL))
1477 return -EPERM;
1478
1479 i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1480 if (i < 0)
1481 return -EINVAL;
1482
1483 aa_g_audit = i;
1484 return 0;
1485}
1486
1487static int param_get_mode(char *buffer, const struct kernel_param *kp)
1488{
1489 if (!apparmor_enabled)
1490 return -EINVAL;
1491 if (apparmor_initialized && !policy_view_capable(NULL))
1492 return -EPERM;
1493
1494 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1495}
1496
1497static int param_set_mode(const char *val, const struct kernel_param *kp)
1498{
1499 int i;
1500
1501 if (!apparmor_enabled)
1502 return -EINVAL;
1503 if (!val)
1504 return -EINVAL;
1505 if (apparmor_initialized && !policy_admin_capable(NULL))
1506 return -EPERM;
1507
1508 i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1509 val);
1510 if (i < 0)
1511 return -EINVAL;
1512
1513 aa_g_profile_mode = i;
1514 return 0;
1515}
1516
1517/*
1518 * AppArmor init functions
1519 */
1520
1521/**
1522 * set_init_ctx - set a task context and profile on the first task.
1523 *
1524 * TODO: allow setting an alternate profile than unconfined
1525 */
1526static int __init set_init_ctx(void)
1527{
1528 struct cred *cred = (struct cred *)current->real_cred;
1529
1530 set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1531
1532 return 0;
1533}
1534
1535static void destroy_buffers(void)
1536{
1537 u32 i, j;
1538
1539 for_each_possible_cpu(i) {
1540 for_each_cpu_buffer(j) {
1541 kfree(per_cpu(aa_buffers, i).buf[j]);
1542 per_cpu(aa_buffers, i).buf[j] = NULL;
1543 }
1544 }
1545}
1546
1547static int __init alloc_buffers(void)
1548{
1549 u32 i, j;
1550
1551 for_each_possible_cpu(i) {
1552 for_each_cpu_buffer(j) {
1553 char *buffer;
1554
1555 if (cpu_to_node(i) > num_online_nodes())
1556 /* fallback to kmalloc for offline nodes */
1557 buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
1558 else
1559 buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
1560 cpu_to_node(i));
1561 if (!buffer) {
1562 destroy_buffers();
1563 return -ENOMEM;
1564 }
1565 per_cpu(aa_buffers, i).buf[j] = buffer;
1566 }
1567 }
1568
1569 return 0;
1570}
1571
1572#ifdef CONFIG_SYSCTL
1573static int apparmor_dointvec(struct ctl_table *table, int write,
1574 void __user *buffer, size_t *lenp, loff_t *ppos)
1575{
1576 if (!policy_admin_capable(NULL))
1577 return -EPERM;
1578 if (!apparmor_enabled)
1579 return -EINVAL;
1580
1581 return proc_dointvec(table, write, buffer, lenp, ppos);
1582}
1583
1584static struct ctl_path apparmor_sysctl_path[] = {
1585 { .procname = "kernel", },
1586 { }
1587};
1588
1589static struct ctl_table apparmor_sysctl_table[] = {
1590 {
1591 .procname = "unprivileged_userns_apparmor_policy",
1592 .data = &unprivileged_userns_apparmor_policy,
1593 .maxlen = sizeof(int),
1594 .mode = 0600,
1595 .proc_handler = apparmor_dointvec,
1596 },
1597 { }
1598};
1599
1600static int __init apparmor_init_sysctl(void)
1601{
1602 return register_sysctl_paths(apparmor_sysctl_path,
1603 apparmor_sysctl_table) ? 0 : -ENOMEM;
1604}
1605#else
1606static inline int apparmor_init_sysctl(void)
1607{
1608 return 0;
1609}
1610#endif /* CONFIG_SYSCTL */
1611
1612#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
1613static unsigned int apparmor_ip_postroute(void *priv,
1614 struct sk_buff *skb,
1615 const struct nf_hook_state *state)
1616{
1617 struct aa_sk_ctx *ctx;
1618 struct sock *sk;
1619
1620 if (!skb->secmark)
1621 return NF_ACCEPT;
1622
1623 sk = skb_to_full_sk(skb);
1624 if (sk == NULL)
1625 return NF_ACCEPT;
1626
1627 ctx = SK_CTX(sk);
1628 if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
1629 skb->secmark, sk))
1630 return NF_ACCEPT;
1631
1632 return NF_DROP_ERR(-ECONNREFUSED);
1633
1634}
1635
1636static unsigned int apparmor_ipv4_postroute(void *priv,
1637 struct sk_buff *skb,
1638 const struct nf_hook_state *state)
1639{
1640 return apparmor_ip_postroute(priv, skb, state);
1641}
1642
1643#if IS_ENABLED(CONFIG_IPV6)
1644static unsigned int apparmor_ipv6_postroute(void *priv,
1645 struct sk_buff *skb,
1646 const struct nf_hook_state *state)
1647{
1648 return apparmor_ip_postroute(priv, skb, state);
1649}
1650#endif
1651
1652static const struct nf_hook_ops apparmor_nf_ops[] = {
1653 {
1654 .hook = apparmor_ipv4_postroute,
1655 .pf = NFPROTO_IPV4,
1656 .hooknum = NF_INET_POST_ROUTING,
1657 .priority = NF_IP_PRI_SELINUX_FIRST,
1658 },
1659#if IS_ENABLED(CONFIG_IPV6)
1660 {
1661 .hook = apparmor_ipv6_postroute,
1662 .pf = NFPROTO_IPV6,
1663 .hooknum = NF_INET_POST_ROUTING,
1664 .priority = NF_IP6_PRI_SELINUX_FIRST,
1665 },
1666#endif
1667};
1668
1669static int __net_init apparmor_nf_register(struct net *net)
1670{
1671 int ret;
1672
1673 ret = nf_register_net_hooks(net, apparmor_nf_ops,
1674 ARRAY_SIZE(apparmor_nf_ops));
1675 return ret;
1676}
1677
1678static void __net_exit apparmor_nf_unregister(struct net *net)
1679{
1680 nf_unregister_net_hooks(net, apparmor_nf_ops,
1681 ARRAY_SIZE(apparmor_nf_ops));
1682}
1683
1684static struct pernet_operations apparmor_net_ops = {
1685 .init = apparmor_nf_register,
1686 .exit = apparmor_nf_unregister,
1687};
1688
1689static int __init apparmor_nf_ip_init(void)
1690{
1691 int err;
1692
1693 if (!apparmor_enabled)
1694 return 0;
1695
1696 err = register_pernet_subsys(&apparmor_net_ops);
1697 if (err)
1698 panic("Apparmor: register_pernet_subsys: error %d\n", err);
1699
1700 return 0;
1701}
1702__initcall(apparmor_nf_ip_init);
1703#endif
1704
1705static int __init apparmor_init(void)
1706{
1707 int error;
1708
1709 aa_secids_init();
1710
1711 error = aa_setup_dfa_engine();
1712 if (error) {
1713 AA_ERROR("Unable to setup dfa engine\n");
1714 goto alloc_out;
1715 }
1716
1717 error = aa_alloc_root_ns();
1718 if (error) {
1719 AA_ERROR("Unable to allocate default profile namespace\n");
1720 goto alloc_out;
1721 }
1722
1723 error = apparmor_init_sysctl();
1724 if (error) {
1725 AA_ERROR("Unable to register sysctls\n");
1726 goto alloc_out;
1727
1728 }
1729
1730 error = alloc_buffers();
1731 if (error) {
1732 AA_ERROR("Unable to allocate work buffers\n");
1733 goto buffers_out;
1734 }
1735
1736 error = set_init_ctx();
1737 if (error) {
1738 AA_ERROR("Failed to set context on init task\n");
1739 aa_free_root_ns();
1740 goto buffers_out;
1741 }
1742 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1743 "apparmor");
1744
1745 /* Report that AppArmor successfully initialized */
1746 apparmor_initialized = 1;
1747 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1748 aa_info_message("AppArmor initialized: complain mode enabled");
1749 else if (aa_g_profile_mode == APPARMOR_KILL)
1750 aa_info_message("AppArmor initialized: kill mode enabled");
1751 else
1752 aa_info_message("AppArmor initialized");
1753
1754 return error;
1755
1756buffers_out:
1757 destroy_buffers();
1758
1759alloc_out:
1760 aa_destroy_aafs();
1761 aa_teardown_dfa_engine();
1762
1763 apparmor_enabled = false;
1764 return error;
1765}
1766
1767DEFINE_LSM(apparmor) = {
1768 .name = "apparmor",
1769 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
1770 .enabled = &apparmor_enabled,
1771 .blobs = &apparmor_blob_sizes,
1772 .init = apparmor_init,
1773};
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/audit.h>
21#include <linux/user_namespace.h>
22#include <linux/netfilter_ipv4.h>
23#include <linux/netfilter_ipv6.h>
24#include <linux/zstd.h>
25#include <net/sock.h>
26#include <uapi/linux/mount.h>
27#include <uapi/linux/lsm.h>
28
29#include "include/apparmor.h"
30#include "include/apparmorfs.h"
31#include "include/audit.h"
32#include "include/capability.h"
33#include "include/cred.h"
34#include "include/file.h"
35#include "include/ipc.h"
36#include "include/net.h"
37#include "include/path.h"
38#include "include/label.h"
39#include "include/policy.h"
40#include "include/policy_ns.h"
41#include "include/procattr.h"
42#include "include/mount.h"
43#include "include/secid.h"
44
45/* Flag indicating whether initialization completed */
46int apparmor_initialized;
47
48union aa_buffer {
49 struct list_head list;
50 DECLARE_FLEX_ARRAY(char, buffer);
51};
52
53struct aa_local_cache {
54 unsigned int hold;
55 unsigned int count;
56 struct list_head head;
57};
58
59#define RESERVE_COUNT 2
60static int reserve_count = RESERVE_COUNT;
61static int buffer_count;
62
63static LIST_HEAD(aa_global_buffers);
64static DEFINE_SPINLOCK(aa_buffers_lock);
65static DEFINE_PER_CPU(struct aa_local_cache, aa_local_buffers);
66
67/*
68 * LSM hook functions
69 */
70
71/*
72 * put the associated labels
73 */
74static void apparmor_cred_free(struct cred *cred)
75{
76 aa_put_label(cred_label(cred));
77 set_cred_label(cred, NULL);
78}
79
80/*
81 * allocate the apparmor part of blank credentials
82 */
83static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
84{
85 set_cred_label(cred, NULL);
86 return 0;
87}
88
89/*
90 * prepare new cred label for modification by prepare_cred block
91 */
92static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
93 gfp_t gfp)
94{
95 set_cred_label(new, aa_get_newest_label(cred_label(old)));
96 return 0;
97}
98
99/*
100 * transfer the apparmor data to a blank set of creds
101 */
102static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
103{
104 set_cred_label(new, aa_get_newest_label(cred_label(old)));
105}
106
107static void apparmor_task_free(struct task_struct *task)
108{
109
110 aa_free_task_ctx(task_ctx(task));
111}
112
113static int apparmor_task_alloc(struct task_struct *task,
114 unsigned long clone_flags)
115{
116 struct aa_task_ctx *new = task_ctx(task);
117
118 aa_dup_task_ctx(new, task_ctx(current));
119
120 return 0;
121}
122
123static int apparmor_ptrace_access_check(struct task_struct *child,
124 unsigned int mode)
125{
126 struct aa_label *tracer, *tracee;
127 const struct cred *cred;
128 int error;
129
130 cred = get_task_cred(child);
131 tracee = cred_label(cred); /* ref count on cred */
132 tracer = __begin_current_label_crit_section();
133 error = aa_may_ptrace(current_cred(), tracer, cred, tracee,
134 (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
135 : AA_PTRACE_TRACE);
136 __end_current_label_crit_section(tracer);
137 put_cred(cred);
138
139 return error;
140}
141
142static int apparmor_ptrace_traceme(struct task_struct *parent)
143{
144 struct aa_label *tracer, *tracee;
145 const struct cred *cred;
146 int error;
147
148 tracee = __begin_current_label_crit_section();
149 cred = get_task_cred(parent);
150 tracer = cred_label(cred); /* ref count on cred */
151 error = aa_may_ptrace(cred, tracer, current_cred(), tracee,
152 AA_PTRACE_TRACE);
153 put_cred(cred);
154 __end_current_label_crit_section(tracee);
155
156 return error;
157}
158
159/* Derived from security/commoncap.c:cap_capget */
160static int apparmor_capget(const struct task_struct *target, kernel_cap_t *effective,
161 kernel_cap_t *inheritable, kernel_cap_t *permitted)
162{
163 struct aa_label *label;
164 const struct cred *cred;
165
166 rcu_read_lock();
167 cred = __task_cred(target);
168 label = aa_get_newest_cred_label(cred);
169
170 /*
171 * cap_capget is stacked ahead of this and will
172 * initialize effective and permitted.
173 */
174 if (!unconfined(label)) {
175 struct aa_profile *profile;
176 struct label_it i;
177
178 label_for_each_confined(i, label, profile) {
179 struct aa_ruleset *rules;
180 if (COMPLAIN_MODE(profile))
181 continue;
182 rules = list_first_entry(&profile->rules,
183 typeof(*rules), list);
184 *effective = cap_intersect(*effective,
185 rules->caps.allow);
186 *permitted = cap_intersect(*permitted,
187 rules->caps.allow);
188 }
189 }
190 rcu_read_unlock();
191 aa_put_label(label);
192
193 return 0;
194}
195
196static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
197 int cap, unsigned int opts)
198{
199 struct aa_label *label;
200 int error = 0;
201
202 label = aa_get_newest_cred_label(cred);
203 if (!unconfined(label))
204 error = aa_capable(cred, label, cap, opts);
205 aa_put_label(label);
206
207 return error;
208}
209
210/**
211 * common_perm - basic common permission check wrapper fn for paths
212 * @op: operation being checked
213 * @path: path to check permission of (NOT NULL)
214 * @mask: requested permissions mask
215 * @cond: conditional info for the permission request (NOT NULL)
216 *
217 * Returns: %0 else error code if error or permission denied
218 */
219static int common_perm(const char *op, const struct path *path, u32 mask,
220 struct path_cond *cond)
221{
222 struct aa_label *label;
223 int error = 0;
224
225 label = __begin_current_label_crit_section();
226 if (!unconfined(label))
227 error = aa_path_perm(op, current_cred(), label, path, 0, mask,
228 cond);
229 __end_current_label_crit_section(label);
230
231 return error;
232}
233
234/**
235 * common_perm_cond - common permission wrapper around inode cond
236 * @op: operation being checked
237 * @path: location to check (NOT NULL)
238 * @mask: requested permissions mask
239 *
240 * Returns: %0 else error code if error or permission denied
241 */
242static int common_perm_cond(const char *op, const struct path *path, u32 mask)
243{
244 vfsuid_t vfsuid = i_uid_into_vfsuid(mnt_idmap(path->mnt),
245 d_backing_inode(path->dentry));
246 struct path_cond cond = {
247 vfsuid_into_kuid(vfsuid),
248 d_backing_inode(path->dentry)->i_mode
249 };
250
251 if (!path_mediated_fs(path->dentry))
252 return 0;
253
254 return common_perm(op, path, mask, &cond);
255}
256
257/**
258 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
259 * @op: operation being checked
260 * @dir: directory of the dentry (NOT NULL)
261 * @dentry: dentry to check (NOT NULL)
262 * @mask: requested permissions mask
263 * @cond: conditional info for the permission request (NOT NULL)
264 *
265 * Returns: %0 else error code if error or permission denied
266 */
267static int common_perm_dir_dentry(const char *op, const struct path *dir,
268 struct dentry *dentry, u32 mask,
269 struct path_cond *cond)
270{
271 struct path path = { .mnt = dir->mnt, .dentry = dentry };
272
273 return common_perm(op, &path, mask, cond);
274}
275
276/**
277 * common_perm_rm - common permission wrapper for operations doing rm
278 * @op: operation being checked
279 * @dir: directory that the dentry is in (NOT NULL)
280 * @dentry: dentry being rm'd (NOT NULL)
281 * @mask: requested permission mask
282 *
283 * Returns: %0 else error code if error or permission denied
284 */
285static int common_perm_rm(const char *op, const struct path *dir,
286 struct dentry *dentry, u32 mask)
287{
288 struct inode *inode = d_backing_inode(dentry);
289 struct path_cond cond = { };
290 vfsuid_t vfsuid;
291
292 if (!inode || !path_mediated_fs(dentry))
293 return 0;
294
295 vfsuid = i_uid_into_vfsuid(mnt_idmap(dir->mnt), inode);
296 cond.uid = vfsuid_into_kuid(vfsuid);
297 cond.mode = inode->i_mode;
298
299 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
300}
301
302/**
303 * common_perm_create - common permission wrapper for operations doing create
304 * @op: operation being checked
305 * @dir: directory that dentry will be created in (NOT NULL)
306 * @dentry: dentry to create (NOT NULL)
307 * @mask: request permission mask
308 * @mode: created file mode
309 *
310 * Returns: %0 else error code if error or permission denied
311 */
312static int common_perm_create(const char *op, const struct path *dir,
313 struct dentry *dentry, u32 mask, umode_t mode)
314{
315 struct path_cond cond = { current_fsuid(), mode };
316
317 if (!path_mediated_fs(dir->dentry))
318 return 0;
319
320 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
321}
322
323static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
324{
325 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
326}
327
328static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
329 umode_t mode)
330{
331 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
332 S_IFDIR);
333}
334
335static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
336{
337 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
338}
339
340static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
341 umode_t mode, unsigned int dev)
342{
343 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
344}
345
346static int apparmor_path_truncate(const struct path *path)
347{
348 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
349}
350
351static int apparmor_file_truncate(struct file *file)
352{
353 return apparmor_path_truncate(&file->f_path);
354}
355
356static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
357 const char *old_name)
358{
359 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
360 S_IFLNK);
361}
362
363static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
364 struct dentry *new_dentry)
365{
366 struct aa_label *label;
367 int error = 0;
368
369 if (!path_mediated_fs(old_dentry))
370 return 0;
371
372 label = begin_current_label_crit_section();
373 if (!unconfined(label))
374 error = aa_path_link(current_cred(), label, old_dentry, new_dir,
375 new_dentry);
376 end_current_label_crit_section(label);
377
378 return error;
379}
380
381static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
382 const struct path *new_dir, struct dentry *new_dentry,
383 const unsigned int flags)
384{
385 struct aa_label *label;
386 int error = 0;
387
388 if (!path_mediated_fs(old_dentry))
389 return 0;
390 if ((flags & RENAME_EXCHANGE) && !path_mediated_fs(new_dentry))
391 return 0;
392
393 label = begin_current_label_crit_section();
394 if (!unconfined(label)) {
395 struct mnt_idmap *idmap = mnt_idmap(old_dir->mnt);
396 vfsuid_t vfsuid;
397 struct path old_path = { .mnt = old_dir->mnt,
398 .dentry = old_dentry };
399 struct path new_path = { .mnt = new_dir->mnt,
400 .dentry = new_dentry };
401 struct path_cond cond = {
402 .mode = d_backing_inode(old_dentry)->i_mode
403 };
404 vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(old_dentry));
405 cond.uid = vfsuid_into_kuid(vfsuid);
406
407 if (flags & RENAME_EXCHANGE) {
408 struct path_cond cond_exchange = {
409 .mode = d_backing_inode(new_dentry)->i_mode,
410 };
411 vfsuid = i_uid_into_vfsuid(idmap, d_backing_inode(old_dentry));
412 cond_exchange.uid = vfsuid_into_kuid(vfsuid);
413
414 error = aa_path_perm(OP_RENAME_SRC, current_cred(),
415 label, &new_path, 0,
416 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
417 AA_MAY_SETATTR | AA_MAY_DELETE,
418 &cond_exchange);
419 if (!error)
420 error = aa_path_perm(OP_RENAME_DEST, current_cred(),
421 label, &old_path,
422 0, MAY_WRITE | AA_MAY_SETATTR |
423 AA_MAY_CREATE, &cond_exchange);
424 }
425
426 if (!error)
427 error = aa_path_perm(OP_RENAME_SRC, current_cred(),
428 label, &old_path, 0,
429 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
430 AA_MAY_SETATTR | AA_MAY_DELETE,
431 &cond);
432 if (!error)
433 error = aa_path_perm(OP_RENAME_DEST, current_cred(),
434 label, &new_path,
435 0, MAY_WRITE | AA_MAY_SETATTR |
436 AA_MAY_CREATE, &cond);
437
438 }
439 end_current_label_crit_section(label);
440
441 return error;
442}
443
444static int apparmor_path_chmod(const struct path *path, umode_t mode)
445{
446 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
447}
448
449static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
450{
451 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
452}
453
454static int apparmor_inode_getattr(const struct path *path)
455{
456 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
457}
458
459static int apparmor_file_open(struct file *file)
460{
461 struct aa_file_ctx *fctx = file_ctx(file);
462 struct aa_label *label;
463 int error = 0;
464 bool needput;
465
466 if (!path_mediated_fs(file->f_path.dentry))
467 return 0;
468
469 /* If in exec, permission is handled by bprm hooks.
470 * Cache permissions granted by the previous exec check, with
471 * implicit read and executable mmap which are required to
472 * actually execute the image.
473 *
474 * Illogically, FMODE_EXEC is in f_flags, not f_mode.
475 */
476 if (file->f_flags & __FMODE_EXEC) {
477 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
478 return 0;
479 }
480
481 label = aa_get_newest_cred_label_condref(file->f_cred, &needput);
482 if (!unconfined(label)) {
483 struct mnt_idmap *idmap = file_mnt_idmap(file);
484 struct inode *inode = file_inode(file);
485 vfsuid_t vfsuid;
486 struct path_cond cond = {
487 .mode = inode->i_mode,
488 };
489 vfsuid = i_uid_into_vfsuid(idmap, inode);
490 cond.uid = vfsuid_into_kuid(vfsuid);
491
492 error = aa_path_perm(OP_OPEN, file->f_cred,
493 label, &file->f_path, 0,
494 aa_map_file_to_perms(file), &cond);
495 /* todo cache full allowed permissions set and state */
496 fctx->allow = aa_map_file_to_perms(file);
497 }
498 aa_put_label_condref(label, needput);
499
500 return error;
501}
502
503static int apparmor_file_alloc_security(struct file *file)
504{
505 struct aa_file_ctx *ctx = file_ctx(file);
506 struct aa_label *label = begin_current_label_crit_section();
507
508 spin_lock_init(&ctx->lock);
509 rcu_assign_pointer(ctx->label, aa_get_label(label));
510 end_current_label_crit_section(label);
511 return 0;
512}
513
514static void apparmor_file_free_security(struct file *file)
515{
516 struct aa_file_ctx *ctx = file_ctx(file);
517
518 if (ctx)
519 aa_put_label(rcu_access_pointer(ctx->label));
520}
521
522static int common_file_perm(const char *op, struct file *file, u32 mask,
523 bool in_atomic)
524{
525 struct aa_label *label;
526 int error = 0;
527
528 /* don't reaudit files closed during inheritance */
529 if (file->f_path.dentry == aa_null.dentry)
530 return -EACCES;
531
532 label = __begin_current_label_crit_section();
533 error = aa_file_perm(op, current_cred(), label, file, mask, in_atomic);
534 __end_current_label_crit_section(label);
535
536 return error;
537}
538
539static int apparmor_file_receive(struct file *file)
540{
541 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
542 false);
543}
544
545static int apparmor_file_permission(struct file *file, int mask)
546{
547 return common_file_perm(OP_FPERM, file, mask, false);
548}
549
550static int apparmor_file_lock(struct file *file, unsigned int cmd)
551{
552 u32 mask = AA_MAY_LOCK;
553
554 if (cmd == F_WRLCK)
555 mask |= MAY_WRITE;
556
557 return common_file_perm(OP_FLOCK, file, mask, false);
558}
559
560static int common_mmap(const char *op, struct file *file, unsigned long prot,
561 unsigned long flags, bool in_atomic)
562{
563 int mask = 0;
564
565 if (!file || !file_ctx(file))
566 return 0;
567
568 if (prot & PROT_READ)
569 mask |= MAY_READ;
570 /*
571 * Private mappings don't require write perms since they don't
572 * write back to the files
573 */
574 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
575 mask |= MAY_WRITE;
576 if (prot & PROT_EXEC)
577 mask |= AA_EXEC_MMAP;
578
579 return common_file_perm(op, file, mask, in_atomic);
580}
581
582static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
583 unsigned long prot, unsigned long flags)
584{
585 return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
586}
587
588static int apparmor_file_mprotect(struct vm_area_struct *vma,
589 unsigned long reqprot, unsigned long prot)
590{
591 return common_mmap(OP_FMPROT, vma->vm_file, prot,
592 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
593 false);
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 = list_first_entry(&profile->rules, typeof(*rules), list);
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 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING,
668 OP_URING_OVERRIDE);
669
670 ad.uring.target = cred_label(new);
671 label = __begin_current_label_crit_section();
672 error = fn_for_each(label, profile,
673 profile_uring(profile, AA_MAY_OVERRIDE_CRED,
674 cred_label(new), CAP_SYS_ADMIN, &ad));
675 __end_current_label_crit_section(label);
676
677 return error;
678}
679
680/**
681 * apparmor_uring_sqpoll - check if a io_uring polling thread can be created
682 *
683 * Check to see if the current task is allowed to create a new io_uring
684 * kernel polling thread.
685 */
686static int apparmor_uring_sqpoll(void)
687{
688 struct aa_profile *profile;
689 struct aa_label *label;
690 int error;
691 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_IO_URING,
692 OP_URING_SQPOLL);
693
694 label = __begin_current_label_crit_section();
695 error = fn_for_each(label, profile,
696 profile_uring(profile, AA_MAY_CREATE_SQPOLL,
697 NULL, CAP_SYS_ADMIN, &ad));
698 __end_current_label_crit_section(label);
699
700 return error;
701}
702#endif /* CONFIG_IO_URING */
703
704static int apparmor_sb_mount(const char *dev_name, const struct path *path,
705 const char *type, unsigned long flags, void *data)
706{
707 struct aa_label *label;
708 int error = 0;
709
710 /* Discard magic */
711 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
712 flags &= ~MS_MGC_MSK;
713
714 flags &= ~AA_MS_IGNORE_MASK;
715
716 label = __begin_current_label_crit_section();
717 if (!unconfined(label)) {
718 if (flags & MS_REMOUNT)
719 error = aa_remount(current_cred(), label, path, flags,
720 data);
721 else if (flags & MS_BIND)
722 error = aa_bind_mount(current_cred(), label, path,
723 dev_name, flags);
724 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
725 MS_UNBINDABLE))
726 error = aa_mount_change_type(current_cred(), label,
727 path, flags);
728 else if (flags & MS_MOVE)
729 error = aa_move_mount_old(current_cred(), label, path,
730 dev_name);
731 else
732 error = aa_new_mount(current_cred(), label, dev_name,
733 path, type, flags, data);
734 }
735 __end_current_label_crit_section(label);
736
737 return error;
738}
739
740static int apparmor_move_mount(const struct path *from_path,
741 const struct path *to_path)
742{
743 struct aa_label *label;
744 int error = 0;
745
746 label = __begin_current_label_crit_section();
747 if (!unconfined(label))
748 error = aa_move_mount(current_cred(), label, from_path,
749 to_path);
750 __end_current_label_crit_section(label);
751
752 return error;
753}
754
755static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
756{
757 struct aa_label *label;
758 int error = 0;
759
760 label = __begin_current_label_crit_section();
761 if (!unconfined(label))
762 error = aa_umount(current_cred(), label, mnt, flags);
763 __end_current_label_crit_section(label);
764
765 return error;
766}
767
768static int apparmor_sb_pivotroot(const struct path *old_path,
769 const struct path *new_path)
770{
771 struct aa_label *label;
772 int error = 0;
773
774 label = aa_get_current_label();
775 if (!unconfined(label))
776 error = aa_pivotroot(current_cred(), label, old_path, new_path);
777 aa_put_label(label);
778
779 return error;
780}
781
782static int apparmor_getselfattr(unsigned int attr, struct lsm_ctx __user *lx,
783 u32 *size, u32 flags)
784{
785 int error = -ENOENT;
786 struct aa_task_ctx *ctx = task_ctx(current);
787 struct aa_label *label = NULL;
788 char *value = NULL;
789
790 switch (attr) {
791 case LSM_ATTR_CURRENT:
792 label = aa_get_newest_label(cred_label(current_cred()));
793 break;
794 case LSM_ATTR_PREV:
795 if (ctx->previous)
796 label = aa_get_newest_label(ctx->previous);
797 break;
798 case LSM_ATTR_EXEC:
799 if (ctx->onexec)
800 label = aa_get_newest_label(ctx->onexec);
801 break;
802 default:
803 error = -EOPNOTSUPP;
804 break;
805 }
806
807 if (label) {
808 error = aa_getprocattr(label, &value, false);
809 if (error > 0)
810 error = lsm_fill_user_ctx(lx, size, value, error,
811 LSM_ID_APPARMOR, 0);
812 kfree(value);
813 }
814
815 aa_put_label(label);
816
817 if (error < 0)
818 return error;
819 return 1;
820}
821
822static int apparmor_getprocattr(struct task_struct *task, const char *name,
823 char **value)
824{
825 int error = -ENOENT;
826 /* released below */
827 const struct cred *cred = get_task_cred(task);
828 struct aa_task_ctx *ctx = task_ctx(current);
829 struct aa_label *label = NULL;
830
831 if (strcmp(name, "current") == 0)
832 label = aa_get_newest_label(cred_label(cred));
833 else if (strcmp(name, "prev") == 0 && ctx->previous)
834 label = aa_get_newest_label(ctx->previous);
835 else if (strcmp(name, "exec") == 0 && ctx->onexec)
836 label = aa_get_newest_label(ctx->onexec);
837 else
838 error = -EINVAL;
839
840 if (label)
841 error = aa_getprocattr(label, value, true);
842
843 aa_put_label(label);
844 put_cred(cred);
845
846 return error;
847}
848
849static int do_setattr(u64 attr, void *value, size_t size)
850{
851 char *command, *largs = NULL, *args = value;
852 size_t arg_size;
853 int error;
854 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_NONE, AA_CLASS_NONE,
855 OP_SETPROCATTR);
856
857 if (size == 0)
858 return -EINVAL;
859
860 /* AppArmor requires that the buffer must be null terminated atm */
861 if (args[size - 1] != '\0') {
862 /* null terminate */
863 largs = args = kmalloc(size + 1, GFP_KERNEL);
864 if (!args)
865 return -ENOMEM;
866 memcpy(args, value, size);
867 args[size] = '\0';
868 }
869
870 error = -EINVAL;
871 args = strim(args);
872 command = strsep(&args, " ");
873 if (!args)
874 goto out;
875 args = skip_spaces(args);
876 if (!*args)
877 goto out;
878
879 arg_size = size - (args - (largs ? largs : (char *) value));
880 if (attr == LSM_ATTR_CURRENT) {
881 if (strcmp(command, "changehat") == 0) {
882 error = aa_setprocattr_changehat(args, arg_size,
883 AA_CHANGE_NOFLAGS);
884 } else if (strcmp(command, "permhat") == 0) {
885 error = aa_setprocattr_changehat(args, arg_size,
886 AA_CHANGE_TEST);
887 } else if (strcmp(command, "changeprofile") == 0) {
888 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
889 } else if (strcmp(command, "permprofile") == 0) {
890 error = aa_change_profile(args, AA_CHANGE_TEST);
891 } else if (strcmp(command, "stack") == 0) {
892 error = aa_change_profile(args, AA_CHANGE_STACK);
893 } else
894 goto fail;
895 } else if (attr == LSM_ATTR_EXEC) {
896 if (strcmp(command, "exec") == 0)
897 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
898 else if (strcmp(command, "stack") == 0)
899 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
900 AA_CHANGE_STACK));
901 else
902 goto fail;
903 } else
904 /* only support the "current" and "exec" process attributes */
905 goto fail;
906
907 if (!error)
908 error = size;
909out:
910 kfree(largs);
911 return error;
912
913fail:
914 ad.subj_label = begin_current_label_crit_section();
915 if (attr == LSM_ATTR_CURRENT)
916 ad.info = "current";
917 else if (attr == LSM_ATTR_EXEC)
918 ad.info = "exec";
919 else
920 ad.info = "invalid";
921 ad.error = error = -EINVAL;
922 aa_audit_msg(AUDIT_APPARMOR_DENIED, &ad, NULL);
923 end_current_label_crit_section(ad.subj_label);
924 goto out;
925}
926
927static int apparmor_setselfattr(unsigned int attr, struct lsm_ctx *ctx,
928 u32 size, u32 flags)
929{
930 int rc;
931
932 if (attr != LSM_ATTR_CURRENT && attr != LSM_ATTR_EXEC)
933 return -EOPNOTSUPP;
934
935 rc = do_setattr(attr, ctx->ctx, ctx->ctx_len);
936 if (rc > 0)
937 return 0;
938 return rc;
939}
940
941static int apparmor_setprocattr(const char *name, void *value,
942 size_t size)
943{
944 int attr = lsm_name_to_attr(name);
945
946 if (attr)
947 return do_setattr(attr, value, size);
948 return -EINVAL;
949}
950
951/**
952 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
953 * @bprm: binprm for the exec (NOT NULL)
954 */
955static void apparmor_bprm_committing_creds(const struct linux_binprm *bprm)
956{
957 struct aa_label *label = aa_current_raw_label();
958 struct aa_label *new_label = cred_label(bprm->cred);
959
960 /* bail out if unconfined or not changing profile */
961 if ((new_label->proxy == label->proxy) ||
962 (unconfined(new_label)))
963 return;
964
965 aa_inherit_files(bprm->cred, current->files);
966
967 current->pdeath_signal = 0;
968
969 /* reset soft limits and set hard limits for the new label */
970 __aa_transition_rlimits(label, new_label);
971}
972
973/**
974 * apparmor_bprm_committed_creds() - do cleanup after new creds committed
975 * @bprm: binprm for the exec (NOT NULL)
976 */
977static void apparmor_bprm_committed_creds(const struct linux_binprm *bprm)
978{
979 /* clear out temporary/transitional state from the context */
980 aa_clear_task_ctx_trans(task_ctx(current));
981
982 return;
983}
984
985static void apparmor_current_getlsmprop_subj(struct lsm_prop *prop)
986{
987 struct aa_label *label = __begin_current_label_crit_section();
988
989 prop->apparmor.label = label;
990 __end_current_label_crit_section(label);
991}
992
993static void apparmor_task_getlsmprop_obj(struct task_struct *p,
994 struct lsm_prop *prop)
995{
996 struct aa_label *label = aa_get_task_label(p);
997
998 prop->apparmor.label = label;
999 aa_put_label(label);
1000}
1001
1002static int apparmor_task_setrlimit(struct task_struct *task,
1003 unsigned int resource, struct rlimit *new_rlim)
1004{
1005 struct aa_label *label = __begin_current_label_crit_section();
1006 int error = 0;
1007
1008 if (!unconfined(label))
1009 error = aa_task_setrlimit(current_cred(), label, task,
1010 resource, new_rlim);
1011 __end_current_label_crit_section(label);
1012
1013 return error;
1014}
1015
1016static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
1017 int sig, const struct cred *cred)
1018{
1019 const struct cred *tc;
1020 struct aa_label *cl, *tl;
1021 int error;
1022
1023 tc = get_task_cred(target);
1024 tl = aa_get_newest_cred_label(tc);
1025 if (cred) {
1026 /*
1027 * Dealing with USB IO specific behavior
1028 */
1029 cl = aa_get_newest_cred_label(cred);
1030 error = aa_may_signal(cred, cl, tc, tl, sig);
1031 aa_put_label(cl);
1032 } else {
1033 cl = __begin_current_label_crit_section();
1034 error = aa_may_signal(current_cred(), cl, tc, tl, sig);
1035 __end_current_label_crit_section(cl);
1036 }
1037 aa_put_label(tl);
1038 put_cred(tc);
1039
1040 return error;
1041}
1042
1043static int apparmor_userns_create(const struct cred *cred)
1044{
1045 struct aa_label *label;
1046 struct aa_profile *profile;
1047 int error = 0;
1048 DEFINE_AUDIT_DATA(ad, LSM_AUDIT_DATA_TASK, AA_CLASS_NS,
1049 OP_USERNS_CREATE);
1050
1051 ad.subj_cred = current_cred();
1052
1053 label = begin_current_label_crit_section();
1054 if (!unconfined(label)) {
1055 error = fn_for_each(label, profile,
1056 aa_profile_ns_perm(profile, &ad,
1057 AA_USERNS_CREATE));
1058 }
1059 end_current_label_crit_section(label);
1060
1061 return error;
1062}
1063
1064static void apparmor_sk_free_security(struct sock *sk)
1065{
1066 struct aa_sk_ctx *ctx = aa_sock(sk);
1067
1068 aa_put_label(ctx->label);
1069 aa_put_label(ctx->peer);
1070}
1071
1072/**
1073 * apparmor_sk_clone_security - clone the sk_security field
1074 * @sk: sock to have security cloned
1075 * @newsk: sock getting clone
1076 */
1077static void apparmor_sk_clone_security(const struct sock *sk,
1078 struct sock *newsk)
1079{
1080 struct aa_sk_ctx *ctx = aa_sock(sk);
1081 struct aa_sk_ctx *new = aa_sock(newsk);
1082
1083 if (new->label)
1084 aa_put_label(new->label);
1085 new->label = aa_get_label(ctx->label);
1086
1087 if (new->peer)
1088 aa_put_label(new->peer);
1089 new->peer = aa_get_label(ctx->peer);
1090}
1091
1092static int apparmor_socket_create(int family, int type, int protocol, int kern)
1093{
1094 struct aa_label *label;
1095 int error = 0;
1096
1097 AA_BUG(in_interrupt());
1098
1099 label = begin_current_label_crit_section();
1100 if (!(kern || unconfined(label)))
1101 error = af_select(family,
1102 create_perm(label, family, type, protocol),
1103 aa_af_perm(current_cred(), label,
1104 OP_CREATE, AA_MAY_CREATE,
1105 family, type, protocol));
1106 end_current_label_crit_section(label);
1107
1108 return error;
1109}
1110
1111/**
1112 * apparmor_socket_post_create - setup the per-socket security struct
1113 * @sock: socket that is being setup
1114 * @family: family of socket being created
1115 * @type: type of the socket
1116 * @protocol: protocol of the socket
1117 * @kern: socket is a special kernel socket
1118 *
1119 * Note:
1120 * - kernel sockets labeled kernel_t used to use unconfined
1121 * - socket may not have sk here if created with sock_create_lite or
1122 * sock_alloc. These should be accept cases which will be handled in
1123 * sock_graft.
1124 */
1125static int apparmor_socket_post_create(struct socket *sock, int family,
1126 int type, int protocol, int kern)
1127{
1128 struct aa_label *label;
1129
1130 if (kern) {
1131 label = aa_get_label(kernel_t);
1132 } else
1133 label = aa_get_current_label();
1134
1135 if (sock->sk) {
1136 struct aa_sk_ctx *ctx = aa_sock(sock->sk);
1137
1138 aa_put_label(ctx->label);
1139 ctx->label = aa_get_label(label);
1140 }
1141 aa_put_label(label);
1142
1143 return 0;
1144}
1145
1146static int apparmor_socket_bind(struct socket *sock,
1147 struct sockaddr *address, int addrlen)
1148{
1149 AA_BUG(!sock);
1150 AA_BUG(!sock->sk);
1151 AA_BUG(!address);
1152 AA_BUG(in_interrupt());
1153
1154 return af_select(sock->sk->sk_family,
1155 bind_perm(sock, address, addrlen),
1156 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
1157}
1158
1159static int apparmor_socket_connect(struct socket *sock,
1160 struct sockaddr *address, int addrlen)
1161{
1162 AA_BUG(!sock);
1163 AA_BUG(!sock->sk);
1164 AA_BUG(!address);
1165 AA_BUG(in_interrupt());
1166
1167 return af_select(sock->sk->sk_family,
1168 connect_perm(sock, address, addrlen),
1169 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
1170}
1171
1172static int apparmor_socket_listen(struct socket *sock, int backlog)
1173{
1174 AA_BUG(!sock);
1175 AA_BUG(!sock->sk);
1176 AA_BUG(in_interrupt());
1177
1178 return af_select(sock->sk->sk_family,
1179 listen_perm(sock, backlog),
1180 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
1181}
1182
1183/*
1184 * Note: while @newsock is created and has some information, the accept
1185 * has not been done.
1186 */
1187static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
1188{
1189 AA_BUG(!sock);
1190 AA_BUG(!sock->sk);
1191 AA_BUG(!newsock);
1192 AA_BUG(in_interrupt());
1193
1194 return af_select(sock->sk->sk_family,
1195 accept_perm(sock, newsock),
1196 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
1197}
1198
1199static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
1200 struct msghdr *msg, int size)
1201{
1202 AA_BUG(!sock);
1203 AA_BUG(!sock->sk);
1204 AA_BUG(!msg);
1205 AA_BUG(in_interrupt());
1206
1207 return af_select(sock->sk->sk_family,
1208 msg_perm(op, request, sock, msg, size),
1209 aa_sk_perm(op, request, sock->sk));
1210}
1211
1212static int apparmor_socket_sendmsg(struct socket *sock,
1213 struct msghdr *msg, int size)
1214{
1215 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
1216}
1217
1218static int apparmor_socket_recvmsg(struct socket *sock,
1219 struct msghdr *msg, int size, int flags)
1220{
1221 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
1222}
1223
1224/* revaliation, get/set attr, shutdown */
1225static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
1226{
1227 AA_BUG(!sock);
1228 AA_BUG(!sock->sk);
1229 AA_BUG(in_interrupt());
1230
1231 return af_select(sock->sk->sk_family,
1232 sock_perm(op, request, sock),
1233 aa_sk_perm(op, request, sock->sk));
1234}
1235
1236static int apparmor_socket_getsockname(struct socket *sock)
1237{
1238 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
1239}
1240
1241static int apparmor_socket_getpeername(struct socket *sock)
1242{
1243 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
1244}
1245
1246/* revaliation, get/set attr, opt */
1247static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
1248 int level, int optname)
1249{
1250 AA_BUG(!sock);
1251 AA_BUG(!sock->sk);
1252 AA_BUG(in_interrupt());
1253
1254 return af_select(sock->sk->sk_family,
1255 opt_perm(op, request, sock, level, optname),
1256 aa_sk_perm(op, request, sock->sk));
1257}
1258
1259static int apparmor_socket_getsockopt(struct socket *sock, int level,
1260 int optname)
1261{
1262 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
1263 level, optname);
1264}
1265
1266static int apparmor_socket_setsockopt(struct socket *sock, int level,
1267 int optname)
1268{
1269 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1270 level, optname);
1271}
1272
1273static int apparmor_socket_shutdown(struct socket *sock, int how)
1274{
1275 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1276}
1277
1278#ifdef CONFIG_NETWORK_SECMARK
1279/**
1280 * apparmor_socket_sock_rcv_skb - check perms before associating skb to sk
1281 * @sk: sk to associate @skb with
1282 * @skb: skb to check for perms
1283 *
1284 * Note: can not sleep may be called with locks held
1285 *
1286 * dont want protocol specific in __skb_recv_datagram()
1287 * to deny an incoming connection socket_sock_rcv_skb()
1288 */
1289static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1290{
1291 struct aa_sk_ctx *ctx = aa_sock(sk);
1292
1293 if (!skb->secmark)
1294 return 0;
1295
1296 /*
1297 * If reach here before socket_post_create hook is called, in which
1298 * case label is null, drop the packet.
1299 */
1300 if (!ctx->label)
1301 return -EACCES;
1302
1303 return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1304 skb->secmark, sk);
1305}
1306#endif
1307
1308
1309static struct aa_label *sk_peer_label(struct sock *sk)
1310{
1311 struct aa_sk_ctx *ctx = aa_sock(sk);
1312
1313 if (ctx->peer)
1314 return ctx->peer;
1315
1316 return ERR_PTR(-ENOPROTOOPT);
1317}
1318
1319/**
1320 * apparmor_socket_getpeersec_stream - get security context of peer
1321 * @sock: socket that we are trying to get the peer context of
1322 * @optval: output - buffer to copy peer name to
1323 * @optlen: output - size of copied name in @optval
1324 * @len: size of @optval buffer
1325 * Returns: 0 on success, -errno of failure
1326 *
1327 * Note: for tcp only valid if using ipsec or cipso on lan
1328 */
1329static int apparmor_socket_getpeersec_stream(struct socket *sock,
1330 sockptr_t optval, sockptr_t optlen,
1331 unsigned int len)
1332{
1333 char *name = NULL;
1334 int slen, error = 0;
1335 struct aa_label *label;
1336 struct aa_label *peer;
1337
1338 label = begin_current_label_crit_section();
1339 peer = sk_peer_label(sock->sk);
1340 if (IS_ERR(peer)) {
1341 error = PTR_ERR(peer);
1342 goto done;
1343 }
1344 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1345 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1346 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1347 /* don't include terminating \0 in slen, it breaks some apps */
1348 if (slen < 0) {
1349 error = -ENOMEM;
1350 goto done;
1351 }
1352 if (slen > len) {
1353 error = -ERANGE;
1354 goto done_len;
1355 }
1356
1357 if (copy_to_sockptr(optval, name, slen))
1358 error = -EFAULT;
1359done_len:
1360 if (copy_to_sockptr(optlen, &slen, sizeof(slen)))
1361 error = -EFAULT;
1362done:
1363 end_current_label_crit_section(label);
1364 kfree(name);
1365 return error;
1366}
1367
1368/**
1369 * apparmor_socket_getpeersec_dgram - get security label of packet
1370 * @sock: the peer socket
1371 * @skb: packet data
1372 * @secid: pointer to where to put the secid of the packet
1373 *
1374 * Sets the netlabel socket state on sk from parent
1375 */
1376static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1377 struct sk_buff *skb, u32 *secid)
1378
1379{
1380 /* TODO: requires secid support */
1381 return -ENOPROTOOPT;
1382}
1383
1384/**
1385 * apparmor_sock_graft - Initialize newly created socket
1386 * @sk: child sock
1387 * @parent: parent socket
1388 *
1389 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1390 * just set sk security information off of current creating process label
1391 * Labeling of sk for accept case - probably should be sock based
1392 * instead of task, because of the case where an implicitly labeled
1393 * socket is shared by different tasks.
1394 */
1395static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1396{
1397 struct aa_sk_ctx *ctx = aa_sock(sk);
1398
1399 if (!ctx->label)
1400 ctx->label = aa_get_current_label();
1401}
1402
1403#ifdef CONFIG_NETWORK_SECMARK
1404static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
1405 struct request_sock *req)
1406{
1407 struct aa_sk_ctx *ctx = aa_sock(sk);
1408
1409 if (!skb->secmark)
1410 return 0;
1411
1412 return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1413 skb->secmark, sk);
1414}
1415#endif
1416
1417/*
1418 * The cred blob is a pointer to, not an instance of, an aa_label.
1419 */
1420struct lsm_blob_sizes apparmor_blob_sizes __ro_after_init = {
1421 .lbs_cred = sizeof(struct aa_label *),
1422 .lbs_file = sizeof(struct aa_file_ctx),
1423 .lbs_task = sizeof(struct aa_task_ctx),
1424 .lbs_sock = sizeof(struct aa_sk_ctx),
1425};
1426
1427static const struct lsm_id apparmor_lsmid = {
1428 .name = "apparmor",
1429 .id = LSM_ID_APPARMOR,
1430};
1431
1432static struct security_hook_list apparmor_hooks[] __ro_after_init = {
1433 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1434 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1435 LSM_HOOK_INIT(capget, apparmor_capget),
1436 LSM_HOOK_INIT(capable, apparmor_capable),
1437
1438 LSM_HOOK_INIT(move_mount, apparmor_move_mount),
1439 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1440 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1441 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1442
1443 LSM_HOOK_INIT(path_link, apparmor_path_link),
1444 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1445 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1446 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1447 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1448 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1449 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1450 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1451 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1452 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1453 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1454
1455 LSM_HOOK_INIT(file_open, apparmor_file_open),
1456 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1457 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1458 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1459 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1460 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1461 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1462 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1463 LSM_HOOK_INIT(file_truncate, apparmor_file_truncate),
1464
1465 LSM_HOOK_INIT(getselfattr, apparmor_getselfattr),
1466 LSM_HOOK_INIT(setselfattr, apparmor_setselfattr),
1467 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1468 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1469
1470 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1471 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1472
1473 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1474 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1475 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1476 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1477 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1478 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1479 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1480 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1481 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1482 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1483 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1484 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1485 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1486#ifdef CONFIG_NETWORK_SECMARK
1487 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1488#endif
1489 LSM_HOOK_INIT(socket_getpeersec_stream,
1490 apparmor_socket_getpeersec_stream),
1491 LSM_HOOK_INIT(socket_getpeersec_dgram,
1492 apparmor_socket_getpeersec_dgram),
1493 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1494#ifdef CONFIG_NETWORK_SECMARK
1495 LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1496#endif
1497
1498 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1499 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1500 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1501 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1502
1503 LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
1504 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1505 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1506
1507 LSM_HOOK_INIT(task_free, apparmor_task_free),
1508 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1509 LSM_HOOK_INIT(current_getlsmprop_subj,
1510 apparmor_current_getlsmprop_subj),
1511 LSM_HOOK_INIT(task_getlsmprop_obj, apparmor_task_getlsmprop_obj),
1512 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1513 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1514 LSM_HOOK_INIT(userns_create, apparmor_userns_create),
1515
1516#ifdef CONFIG_AUDIT
1517 LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1518 LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1519 LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1520 LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1521#endif
1522
1523 LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1524 LSM_HOOK_INIT(lsmprop_to_secctx, apparmor_lsmprop_to_secctx),
1525 LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1526 LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1527
1528#ifdef CONFIG_IO_URING
1529 LSM_HOOK_INIT(uring_override_creds, apparmor_uring_override_creds),
1530 LSM_HOOK_INIT(uring_sqpoll, apparmor_uring_sqpoll),
1531#endif
1532};
1533
1534/*
1535 * AppArmor sysfs module parameters
1536 */
1537
1538static int param_set_aabool(const char *val, const struct kernel_param *kp);
1539static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1540#define param_check_aabool param_check_bool
1541static const struct kernel_param_ops param_ops_aabool = {
1542 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1543 .set = param_set_aabool,
1544 .get = param_get_aabool
1545};
1546
1547static int param_set_aauint(const char *val, const struct kernel_param *kp);
1548static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1549#define param_check_aauint param_check_uint
1550static const struct kernel_param_ops param_ops_aauint = {
1551 .set = param_set_aauint,
1552 .get = param_get_aauint
1553};
1554
1555static int param_set_aacompressionlevel(const char *val,
1556 const struct kernel_param *kp);
1557static int param_get_aacompressionlevel(char *buffer,
1558 const struct kernel_param *kp);
1559#define param_check_aacompressionlevel param_check_int
1560static const struct kernel_param_ops param_ops_aacompressionlevel = {
1561 .set = param_set_aacompressionlevel,
1562 .get = param_get_aacompressionlevel
1563};
1564
1565static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1566static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1567#define param_check_aalockpolicy param_check_bool
1568static const struct kernel_param_ops param_ops_aalockpolicy = {
1569 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1570 .set = param_set_aalockpolicy,
1571 .get = param_get_aalockpolicy
1572};
1573
1574static int param_set_audit(const char *val, const struct kernel_param *kp);
1575static int param_get_audit(char *buffer, const struct kernel_param *kp);
1576
1577static int param_set_mode(const char *val, const struct kernel_param *kp);
1578static int param_get_mode(char *buffer, const struct kernel_param *kp);
1579
1580/* Flag values, also controllable via /sys/module/apparmor/parameters
1581 * We define special types as we want to do additional mediation.
1582 */
1583
1584/* AppArmor global enforcement switch - complain, enforce, kill */
1585enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1586module_param_call(mode, param_set_mode, param_get_mode,
1587 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1588
1589/* whether policy verification hashing is enabled */
1590bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1591#ifdef CONFIG_SECURITY_APPARMOR_HASH
1592module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1593#endif
1594
1595/* whether policy exactly as loaded is retained for debug and checkpointing */
1596bool aa_g_export_binary = IS_ENABLED(CONFIG_SECURITY_APPARMOR_EXPORT_BINARY);
1597#ifdef CONFIG_SECURITY_APPARMOR_EXPORT_BINARY
1598module_param_named(export_binary, aa_g_export_binary, aabool, 0600);
1599#endif
1600
1601/* policy loaddata compression level */
1602int aa_g_rawdata_compression_level = AA_DEFAULT_CLEVEL;
1603module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
1604 aacompressionlevel, 0400);
1605
1606/* Debug mode */
1607bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1608module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1609
1610/* Audit mode */
1611enum audit_mode aa_g_audit;
1612module_param_call(audit, param_set_audit, param_get_audit,
1613 &aa_g_audit, S_IRUSR | S_IWUSR);
1614
1615/* Determines if audit header is included in audited messages. This
1616 * provides more context if the audit daemon is not running
1617 */
1618bool aa_g_audit_header = true;
1619module_param_named(audit_header, aa_g_audit_header, aabool,
1620 S_IRUSR | S_IWUSR);
1621
1622/* lock out loading/removal of policy
1623 * TODO: add in at boot loading of policy, which is the only way to
1624 * load policy, if lock_policy is set
1625 */
1626bool aa_g_lock_policy;
1627module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1628 S_IRUSR | S_IWUSR);
1629
1630/* Syscall logging mode */
1631bool aa_g_logsyscall;
1632module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1633
1634/* Maximum pathname length before accesses will start getting rejected */
1635unsigned int aa_g_path_max = 2 * PATH_MAX;
1636module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1637
1638/* Determines how paranoid loading of policy is and how much verification
1639 * on the loaded policy is done.
1640 * DEPRECATED: read only as strict checking of load is always done now
1641 * that none root users (user namespaces) can load policy.
1642 */
1643bool aa_g_paranoid_load = IS_ENABLED(CONFIG_SECURITY_APPARMOR_PARANOID_LOAD);
1644module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1645
1646static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1647static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1648#define param_check_aaintbool param_check_int
1649static const struct kernel_param_ops param_ops_aaintbool = {
1650 .set = param_set_aaintbool,
1651 .get = param_get_aaintbool
1652};
1653/* Boot time disable flag */
1654static int apparmor_enabled __ro_after_init = 1;
1655module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1656
1657static int __init apparmor_enabled_setup(char *str)
1658{
1659 unsigned long enabled;
1660 int error = kstrtoul(str, 0, &enabled);
1661 if (!error)
1662 apparmor_enabled = enabled ? 1 : 0;
1663 return 1;
1664}
1665
1666__setup("apparmor=", apparmor_enabled_setup);
1667
1668/* set global flag turning off the ability to load policy */
1669static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1670{
1671 if (!apparmor_enabled)
1672 return -EINVAL;
1673 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1674 return -EPERM;
1675 return param_set_bool(val, kp);
1676}
1677
1678static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1679{
1680 if (!apparmor_enabled)
1681 return -EINVAL;
1682 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1683 return -EPERM;
1684 return param_get_bool(buffer, kp);
1685}
1686
1687static int param_set_aabool(const char *val, const struct kernel_param *kp)
1688{
1689 if (!apparmor_enabled)
1690 return -EINVAL;
1691 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1692 return -EPERM;
1693 return param_set_bool(val, kp);
1694}
1695
1696static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1697{
1698 if (!apparmor_enabled)
1699 return -EINVAL;
1700 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1701 return -EPERM;
1702 return param_get_bool(buffer, kp);
1703}
1704
1705static int param_set_aauint(const char *val, const struct kernel_param *kp)
1706{
1707 int error;
1708
1709 if (!apparmor_enabled)
1710 return -EINVAL;
1711 /* file is ro but enforce 2nd line check */
1712 if (apparmor_initialized)
1713 return -EPERM;
1714
1715 error = param_set_uint(val, kp);
1716 aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
1717 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1718
1719 return error;
1720}
1721
1722static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1723{
1724 if (!apparmor_enabled)
1725 return -EINVAL;
1726 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1727 return -EPERM;
1728 return param_get_uint(buffer, kp);
1729}
1730
1731/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1732static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1733{
1734 struct kernel_param kp_local;
1735 bool value;
1736 int error;
1737
1738 if (apparmor_initialized)
1739 return -EPERM;
1740
1741 /* Create local copy, with arg pointing to bool type. */
1742 value = !!*((int *)kp->arg);
1743 memcpy(&kp_local, kp, sizeof(kp_local));
1744 kp_local.arg = &value;
1745
1746 error = param_set_bool(val, &kp_local);
1747 if (!error)
1748 *((int *)kp->arg) = *((bool *)kp_local.arg);
1749 return error;
1750}
1751
1752/*
1753 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1754 * 1/0, this converts the "int that is actually bool" back to bool for
1755 * display in the /sys filesystem, while keeping it "int" for the LSM
1756 * infrastructure.
1757 */
1758static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1759{
1760 struct kernel_param kp_local;
1761 bool value;
1762
1763 /* Create local copy, with arg pointing to bool type. */
1764 value = !!*((int *)kp->arg);
1765 memcpy(&kp_local, kp, sizeof(kp_local));
1766 kp_local.arg = &value;
1767
1768 return param_get_bool(buffer, &kp_local);
1769}
1770
1771static int param_set_aacompressionlevel(const char *val,
1772 const struct kernel_param *kp)
1773{
1774 int error;
1775
1776 if (!apparmor_enabled)
1777 return -EINVAL;
1778 if (apparmor_initialized)
1779 return -EPERM;
1780
1781 error = param_set_int(val, kp);
1782
1783 aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
1784 AA_MIN_CLEVEL, AA_MAX_CLEVEL);
1785 pr_info("AppArmor: policy rawdata compression level set to %d\n",
1786 aa_g_rawdata_compression_level);
1787
1788 return error;
1789}
1790
1791static int param_get_aacompressionlevel(char *buffer,
1792 const struct kernel_param *kp)
1793{
1794 if (!apparmor_enabled)
1795 return -EINVAL;
1796 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1797 return -EPERM;
1798 return param_get_int(buffer, kp);
1799}
1800
1801static int param_get_audit(char *buffer, const struct kernel_param *kp)
1802{
1803 if (!apparmor_enabled)
1804 return -EINVAL;
1805 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1806 return -EPERM;
1807 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1808}
1809
1810static int param_set_audit(const char *val, const struct kernel_param *kp)
1811{
1812 int i;
1813
1814 if (!apparmor_enabled)
1815 return -EINVAL;
1816 if (!val)
1817 return -EINVAL;
1818 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1819 return -EPERM;
1820
1821 i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1822 if (i < 0)
1823 return -EINVAL;
1824
1825 aa_g_audit = i;
1826 return 0;
1827}
1828
1829static int param_get_mode(char *buffer, const struct kernel_param *kp)
1830{
1831 if (!apparmor_enabled)
1832 return -EINVAL;
1833 if (apparmor_initialized && !aa_current_policy_view_capable(NULL))
1834 return -EPERM;
1835
1836 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1837}
1838
1839static int param_set_mode(const char *val, const struct kernel_param *kp)
1840{
1841 int i;
1842
1843 if (!apparmor_enabled)
1844 return -EINVAL;
1845 if (!val)
1846 return -EINVAL;
1847 if (apparmor_initialized && !aa_current_policy_admin_capable(NULL))
1848 return -EPERM;
1849
1850 i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1851 val);
1852 if (i < 0)
1853 return -EINVAL;
1854
1855 aa_g_profile_mode = i;
1856 return 0;
1857}
1858
1859char *aa_get_buffer(bool in_atomic)
1860{
1861 union aa_buffer *aa_buf;
1862 struct aa_local_cache *cache;
1863 bool try_again = true;
1864 gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1865
1866 /* use per cpu cached buffers first */
1867 cache = get_cpu_ptr(&aa_local_buffers);
1868 if (!list_empty(&cache->head)) {
1869 aa_buf = list_first_entry(&cache->head, union aa_buffer, list);
1870 list_del(&aa_buf->list);
1871 cache->hold--;
1872 cache->count--;
1873 put_cpu_ptr(&aa_local_buffers);
1874 return &aa_buf->buffer[0];
1875 }
1876 put_cpu_ptr(&aa_local_buffers);
1877
1878 if (!spin_trylock(&aa_buffers_lock)) {
1879 cache = get_cpu_ptr(&aa_local_buffers);
1880 cache->hold += 1;
1881 put_cpu_ptr(&aa_local_buffers);
1882 spin_lock(&aa_buffers_lock);
1883 } else {
1884 cache = get_cpu_ptr(&aa_local_buffers);
1885 put_cpu_ptr(&aa_local_buffers);
1886 }
1887retry:
1888 if (buffer_count > reserve_count ||
1889 (in_atomic && !list_empty(&aa_global_buffers))) {
1890 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1891 list);
1892 list_del(&aa_buf->list);
1893 buffer_count--;
1894 spin_unlock(&aa_buffers_lock);
1895 return aa_buf->buffer;
1896 }
1897 if (in_atomic) {
1898 /*
1899 * out of reserve buffers and in atomic context so increase
1900 * how many buffers to keep in reserve
1901 */
1902 reserve_count++;
1903 flags = GFP_ATOMIC;
1904 }
1905 spin_unlock(&aa_buffers_lock);
1906
1907 if (!in_atomic)
1908 might_sleep();
1909 aa_buf = kmalloc(aa_g_path_max, flags);
1910 if (!aa_buf) {
1911 if (try_again) {
1912 try_again = false;
1913 spin_lock(&aa_buffers_lock);
1914 goto retry;
1915 }
1916 pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
1917 return NULL;
1918 }
1919 return aa_buf->buffer;
1920}
1921
1922void aa_put_buffer(char *buf)
1923{
1924 union aa_buffer *aa_buf;
1925 struct aa_local_cache *cache;
1926
1927 if (!buf)
1928 return;
1929 aa_buf = container_of(buf, union aa_buffer, buffer[0]);
1930
1931 cache = get_cpu_ptr(&aa_local_buffers);
1932 if (!cache->hold) {
1933 put_cpu_ptr(&aa_local_buffers);
1934
1935 if (spin_trylock(&aa_buffers_lock)) {
1936 /* put back on global list */
1937 list_add(&aa_buf->list, &aa_global_buffers);
1938 buffer_count++;
1939 spin_unlock(&aa_buffers_lock);
1940 cache = get_cpu_ptr(&aa_local_buffers);
1941 put_cpu_ptr(&aa_local_buffers);
1942 return;
1943 }
1944 /* contention on global list, fallback to percpu */
1945 cache = get_cpu_ptr(&aa_local_buffers);
1946 cache->hold += 1;
1947 }
1948
1949 /* cache in percpu list */
1950 list_add(&aa_buf->list, &cache->head);
1951 cache->count++;
1952 put_cpu_ptr(&aa_local_buffers);
1953}
1954
1955/*
1956 * AppArmor init functions
1957 */
1958
1959/**
1960 * set_init_ctx - set a task context and profile on the first task.
1961 *
1962 * TODO: allow setting an alternate profile than unconfined
1963 */
1964static int __init set_init_ctx(void)
1965{
1966 struct cred *cred = (__force struct cred *)current->real_cred;
1967
1968 set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1969
1970 return 0;
1971}
1972
1973static void destroy_buffers(void)
1974{
1975 union aa_buffer *aa_buf;
1976
1977 spin_lock(&aa_buffers_lock);
1978 while (!list_empty(&aa_global_buffers)) {
1979 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1980 list);
1981 list_del(&aa_buf->list);
1982 spin_unlock(&aa_buffers_lock);
1983 kfree(aa_buf);
1984 spin_lock(&aa_buffers_lock);
1985 }
1986 spin_unlock(&aa_buffers_lock);
1987}
1988
1989static int __init alloc_buffers(void)
1990{
1991 union aa_buffer *aa_buf;
1992 int i, num;
1993
1994 /*
1995 * per cpu set of cached allocated buffers used to help reduce
1996 * lock contention
1997 */
1998 for_each_possible_cpu(i) {
1999 per_cpu(aa_local_buffers, i).hold = 0;
2000 per_cpu(aa_local_buffers, i).count = 0;
2001 INIT_LIST_HEAD(&per_cpu(aa_local_buffers, i).head);
2002 }
2003 /*
2004 * A function may require two buffers at once. Usually the buffers are
2005 * used for a short period of time and are shared. On UP kernel buffers
2006 * two should be enough, with more CPUs it is possible that more
2007 * buffers will be used simultaneously. The preallocated pool may grow.
2008 * This preallocation has also the side-effect that AppArmor will be
2009 * disabled early at boot if aa_g_path_max is extremly high.
2010 */
2011 if (num_online_cpus() > 1)
2012 num = 4 + RESERVE_COUNT;
2013 else
2014 num = 2 + RESERVE_COUNT;
2015
2016 for (i = 0; i < num; i++) {
2017
2018 aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
2019 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
2020 if (!aa_buf) {
2021 destroy_buffers();
2022 return -ENOMEM;
2023 }
2024 aa_put_buffer(aa_buf->buffer);
2025 }
2026 return 0;
2027}
2028
2029#ifdef CONFIG_SYSCTL
2030static int apparmor_dointvec(const struct ctl_table *table, int write,
2031 void *buffer, size_t *lenp, loff_t *ppos)
2032{
2033 if (!aa_current_policy_admin_capable(NULL))
2034 return -EPERM;
2035 if (!apparmor_enabled)
2036 return -EINVAL;
2037
2038 return proc_dointvec(table, write, buffer, lenp, ppos);
2039}
2040
2041static struct ctl_table apparmor_sysctl_table[] = {
2042#ifdef CONFIG_USER_NS
2043 {
2044 .procname = "unprivileged_userns_apparmor_policy",
2045 .data = &unprivileged_userns_apparmor_policy,
2046 .maxlen = sizeof(int),
2047 .mode = 0600,
2048 .proc_handler = apparmor_dointvec,
2049 },
2050#endif /* CONFIG_USER_NS */
2051 {
2052 .procname = "apparmor_display_secid_mode",
2053 .data = &apparmor_display_secid_mode,
2054 .maxlen = sizeof(int),
2055 .mode = 0600,
2056 .proc_handler = apparmor_dointvec,
2057 },
2058 {
2059 .procname = "apparmor_restrict_unprivileged_unconfined",
2060 .data = &aa_unprivileged_unconfined_restricted,
2061 .maxlen = sizeof(int),
2062 .mode = 0600,
2063 .proc_handler = apparmor_dointvec,
2064 },
2065};
2066
2067static int __init apparmor_init_sysctl(void)
2068{
2069 return register_sysctl("kernel", apparmor_sysctl_table) ? 0 : -ENOMEM;
2070}
2071#else
2072static inline int apparmor_init_sysctl(void)
2073{
2074 return 0;
2075}
2076#endif /* CONFIG_SYSCTL */
2077
2078#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
2079static unsigned int apparmor_ip_postroute(void *priv,
2080 struct sk_buff *skb,
2081 const struct nf_hook_state *state)
2082{
2083 struct aa_sk_ctx *ctx;
2084 struct sock *sk;
2085
2086 if (!skb->secmark)
2087 return NF_ACCEPT;
2088
2089 sk = skb_to_full_sk(skb);
2090 if (sk == NULL)
2091 return NF_ACCEPT;
2092
2093 ctx = aa_sock(sk);
2094 if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
2095 skb->secmark, sk))
2096 return NF_ACCEPT;
2097
2098 return NF_DROP_ERR(-ECONNREFUSED);
2099
2100}
2101
2102static const struct nf_hook_ops apparmor_nf_ops[] = {
2103 {
2104 .hook = apparmor_ip_postroute,
2105 .pf = NFPROTO_IPV4,
2106 .hooknum = NF_INET_POST_ROUTING,
2107 .priority = NF_IP_PRI_SELINUX_FIRST,
2108 },
2109#if IS_ENABLED(CONFIG_IPV6)
2110 {
2111 .hook = apparmor_ip_postroute,
2112 .pf = NFPROTO_IPV6,
2113 .hooknum = NF_INET_POST_ROUTING,
2114 .priority = NF_IP6_PRI_SELINUX_FIRST,
2115 },
2116#endif
2117};
2118
2119static int __net_init apparmor_nf_register(struct net *net)
2120{
2121 return nf_register_net_hooks(net, apparmor_nf_ops,
2122 ARRAY_SIZE(apparmor_nf_ops));
2123}
2124
2125static void __net_exit apparmor_nf_unregister(struct net *net)
2126{
2127 nf_unregister_net_hooks(net, apparmor_nf_ops,
2128 ARRAY_SIZE(apparmor_nf_ops));
2129}
2130
2131static struct pernet_operations apparmor_net_ops = {
2132 .init = apparmor_nf_register,
2133 .exit = apparmor_nf_unregister,
2134};
2135
2136static int __init apparmor_nf_ip_init(void)
2137{
2138 int err;
2139
2140 if (!apparmor_enabled)
2141 return 0;
2142
2143 err = register_pernet_subsys(&apparmor_net_ops);
2144 if (err)
2145 panic("Apparmor: register_pernet_subsys: error %d\n", err);
2146
2147 return 0;
2148}
2149__initcall(apparmor_nf_ip_init);
2150#endif
2151
2152static char nulldfa_src[] = {
2153 #include "nulldfa.in"
2154};
2155static struct aa_dfa *nulldfa;
2156
2157static char stacksplitdfa_src[] = {
2158 #include "stacksplitdfa.in"
2159};
2160struct aa_dfa *stacksplitdfa;
2161struct aa_policydb *nullpdb;
2162
2163static int __init aa_setup_dfa_engine(void)
2164{
2165 int error = -ENOMEM;
2166
2167 nullpdb = aa_alloc_pdb(GFP_KERNEL);
2168 if (!nullpdb)
2169 return -ENOMEM;
2170
2171 nulldfa = aa_dfa_unpack(nulldfa_src, sizeof(nulldfa_src),
2172 TO_ACCEPT1_FLAG(YYTD_DATA32) |
2173 TO_ACCEPT2_FLAG(YYTD_DATA32));
2174 if (IS_ERR(nulldfa)) {
2175 error = PTR_ERR(nulldfa);
2176 goto fail;
2177 }
2178 nullpdb->dfa = aa_get_dfa(nulldfa);
2179 nullpdb->perms = kcalloc(2, sizeof(struct aa_perms), GFP_KERNEL);
2180 if (!nullpdb->perms)
2181 goto fail;
2182 nullpdb->size = 2;
2183
2184 stacksplitdfa = aa_dfa_unpack(stacksplitdfa_src,
2185 sizeof(stacksplitdfa_src),
2186 TO_ACCEPT1_FLAG(YYTD_DATA32) |
2187 TO_ACCEPT2_FLAG(YYTD_DATA32));
2188 if (IS_ERR(stacksplitdfa)) {
2189 error = PTR_ERR(stacksplitdfa);
2190 goto fail;
2191 }
2192
2193 return 0;
2194
2195fail:
2196 aa_put_pdb(nullpdb);
2197 aa_put_dfa(nulldfa);
2198 nullpdb = NULL;
2199 nulldfa = NULL;
2200 stacksplitdfa = NULL;
2201
2202 return error;
2203}
2204
2205static void __init aa_teardown_dfa_engine(void)
2206{
2207 aa_put_dfa(stacksplitdfa);
2208 aa_put_dfa(nulldfa);
2209 aa_put_pdb(nullpdb);
2210 nullpdb = NULL;
2211 stacksplitdfa = NULL;
2212 nulldfa = NULL;
2213}
2214
2215static int __init apparmor_init(void)
2216{
2217 int error;
2218
2219 error = aa_setup_dfa_engine();
2220 if (error) {
2221 AA_ERROR("Unable to setup dfa engine\n");
2222 goto alloc_out;
2223 }
2224
2225 error = aa_alloc_root_ns();
2226 if (error) {
2227 AA_ERROR("Unable to allocate default profile namespace\n");
2228 goto alloc_out;
2229 }
2230
2231 error = apparmor_init_sysctl();
2232 if (error) {
2233 AA_ERROR("Unable to register sysctls\n");
2234 goto alloc_out;
2235
2236 }
2237
2238 error = alloc_buffers();
2239 if (error) {
2240 AA_ERROR("Unable to allocate work buffers\n");
2241 goto alloc_out;
2242 }
2243
2244 error = set_init_ctx();
2245 if (error) {
2246 AA_ERROR("Failed to set context on init task\n");
2247 aa_free_root_ns();
2248 goto buffers_out;
2249 }
2250 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
2251 &apparmor_lsmid);
2252
2253 /* Report that AppArmor successfully initialized */
2254 apparmor_initialized = 1;
2255 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
2256 aa_info_message("AppArmor initialized: complain mode enabled");
2257 else if (aa_g_profile_mode == APPARMOR_KILL)
2258 aa_info_message("AppArmor initialized: kill mode enabled");
2259 else
2260 aa_info_message("AppArmor initialized");
2261
2262 return error;
2263
2264buffers_out:
2265 destroy_buffers();
2266alloc_out:
2267 aa_destroy_aafs();
2268 aa_teardown_dfa_engine();
2269
2270 apparmor_enabled = false;
2271 return error;
2272}
2273
2274DEFINE_LSM(apparmor) = {
2275 .name = "apparmor",
2276 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
2277 .enabled = &apparmor_enabled,
2278 .blobs = &apparmor_blob_sizes,
2279 .init = apparmor_init,
2280};