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Merge tag 'apparmor-pr-2018-04-10' of git://git.kernel.org/pub/scm/linux/kernel/git...
[thirdparty/kernel/stable.git] / security / apparmor / lsm.c
1 /*
2 * AppArmor security module
3 *
4 * This file contains AppArmor LSM hooks.
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
12 * License.
13 */
14
15 #include <linux/lsm_hooks.h>
16 #include <linux/moduleparam.h>
17 #include <linux/mm.h>
18 #include <linux/mman.h>
19 #include <linux/mount.h>
20 #include <linux/namei.h>
21 #include <linux/ptrace.h>
22 #include <linux/ctype.h>
23 #include <linux/sysctl.h>
24 #include <linux/audit.h>
25 #include <linux/user_namespace.h>
26 #include <net/sock.h>
27
28 #include "include/apparmor.h"
29 #include "include/apparmorfs.h"
30 #include "include/audit.h"
31 #include "include/capability.h"
32 #include "include/cred.h"
33 #include "include/file.h"
34 #include "include/ipc.h"
35 #include "include/net.h"
36 #include "include/path.h"
37 #include "include/label.h"
38 #include "include/policy.h"
39 #include "include/policy_ns.h"
40 #include "include/procattr.h"
41 #include "include/mount.h"
42
43 /* Flag indicating whether initialization completed */
44 int apparmor_initialized;
45
46 DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
47
48
49 /*
50 * LSM hook functions
51 */
52
53 /*
54 * put the associated labels
55 */
56 static void apparmor_cred_free(struct cred *cred)
57 {
58 aa_put_label(cred_label(cred));
59 cred_label(cred) = NULL;
60 }
61
62 /*
63 * allocate the apparmor part of blank credentials
64 */
65 static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
66 {
67 cred_label(cred) = NULL;
68 return 0;
69 }
70
71 /*
72 * prepare new cred label for modification by prepare_cred block
73 */
74 static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
75 gfp_t gfp)
76 {
77 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 */
84 static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
85 {
86 cred_label(new) = aa_get_newest_label(cred_label(old));
87 }
88
89 static void apparmor_task_free(struct task_struct *task)
90 {
91
92 aa_free_task_ctx(task_ctx(task));
93 task_ctx(task) = NULL;
94 }
95
96 static int apparmor_task_alloc(struct task_struct *task,
97 unsigned long clone_flags)
98 {
99 struct aa_task_ctx *new = aa_alloc_task_ctx(GFP_KERNEL);
100
101 if (!new)
102 return -ENOMEM;
103
104 aa_dup_task_ctx(new, task_ctx(current));
105 task_ctx(task) = new;
106
107 return 0;
108 }
109
110 static int apparmor_ptrace_access_check(struct task_struct *child,
111 unsigned int mode)
112 {
113 struct aa_label *tracer, *tracee;
114 int error;
115
116 tracer = begin_current_label_crit_section();
117 tracee = aa_get_task_label(child);
118 error = aa_may_ptrace(tracer, tracee,
119 mode == PTRACE_MODE_READ ? AA_PTRACE_READ : AA_PTRACE_TRACE);
120 aa_put_label(tracee);
121 end_current_label_crit_section(tracer);
122
123 return error;
124 }
125
126 static int apparmor_ptrace_traceme(struct task_struct *parent)
127 {
128 struct aa_label *tracer, *tracee;
129 int error;
130
131 tracee = begin_current_label_crit_section();
132 tracer = aa_get_task_label(parent);
133 error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
134 aa_put_label(tracer);
135 end_current_label_crit_section(tracee);
136
137 return error;
138 }
139
140 /* Derived from security/commoncap.c:cap_capget */
141 static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
142 kernel_cap_t *inheritable, kernel_cap_t *permitted)
143 {
144 struct aa_label *label;
145 const struct cred *cred;
146
147 rcu_read_lock();
148 cred = __task_cred(target);
149 label = aa_get_newest_cred_label(cred);
150
151 /*
152 * cap_capget is stacked ahead of this and will
153 * initialize effective and permitted.
154 */
155 if (!unconfined(label)) {
156 struct aa_profile *profile;
157 struct label_it i;
158
159 label_for_each_confined(i, label, profile) {
160 if (COMPLAIN_MODE(profile))
161 continue;
162 *effective = cap_intersect(*effective,
163 profile->caps.allow);
164 *permitted = cap_intersect(*permitted,
165 profile->caps.allow);
166 }
167 }
168 rcu_read_unlock();
169 aa_put_label(label);
170
171 return 0;
172 }
173
174 static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
175 int cap, int audit)
176 {
177 struct aa_label *label;
178 int error = 0;
179
180 label = aa_get_newest_cred_label(cred);
181 if (!unconfined(label))
182 error = aa_capable(label, cap, audit);
183 aa_put_label(label);
184
185 return error;
186 }
187
188 /**
189 * common_perm - basic common permission check wrapper fn for paths
190 * @op: operation being checked
191 * @path: path to check permission of (NOT NULL)
192 * @mask: requested permissions mask
193 * @cond: conditional info for the permission request (NOT NULL)
194 *
195 * Returns: %0 else error code if error or permission denied
196 */
197 static int common_perm(const char *op, const struct path *path, u32 mask,
198 struct path_cond *cond)
199 {
200 struct aa_label *label;
201 int error = 0;
202
203 label = __begin_current_label_crit_section();
204 if (!unconfined(label))
205 error = aa_path_perm(op, label, path, 0, mask, cond);
206 __end_current_label_crit_section(label);
207
208 return error;
209 }
210
211 /**
212 * common_perm_cond - common permission wrapper around inode cond
213 * @op: operation being checked
214 * @path: location to check (NOT NULL)
215 * @mask: requested permissions mask
216 *
217 * Returns: %0 else error code if error or permission denied
218 */
219 static int common_perm_cond(const char *op, const struct path *path, u32 mask)
220 {
221 struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
222 d_backing_inode(path->dentry)->i_mode
223 };
224
225 if (!path_mediated_fs(path->dentry))
226 return 0;
227
228 return common_perm(op, path, mask, &cond);
229 }
230
231 /**
232 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
233 * @op: operation being checked
234 * @dir: directory of the dentry (NOT NULL)
235 * @dentry: dentry to check (NOT NULL)
236 * @mask: requested permissions mask
237 * @cond: conditional info for the permission request (NOT NULL)
238 *
239 * Returns: %0 else error code if error or permission denied
240 */
241 static int common_perm_dir_dentry(const char *op, const struct path *dir,
242 struct dentry *dentry, u32 mask,
243 struct path_cond *cond)
244 {
245 struct path path = { .mnt = dir->mnt, .dentry = dentry };
246
247 return common_perm(op, &path, mask, cond);
248 }
249
250 /**
251 * common_perm_rm - common permission wrapper for operations doing rm
252 * @op: operation being checked
253 * @dir: directory that the dentry is in (NOT NULL)
254 * @dentry: dentry being rm'd (NOT NULL)
255 * @mask: requested permission mask
256 *
257 * Returns: %0 else error code if error or permission denied
258 */
259 static int common_perm_rm(const char *op, const struct path *dir,
260 struct dentry *dentry, u32 mask)
261 {
262 struct inode *inode = d_backing_inode(dentry);
263 struct path_cond cond = { };
264
265 if (!inode || !path_mediated_fs(dentry))
266 return 0;
267
268 cond.uid = inode->i_uid;
269 cond.mode = inode->i_mode;
270
271 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
272 }
273
274 /**
275 * common_perm_create - common permission wrapper for operations doing create
276 * @op: operation being checked
277 * @dir: directory that dentry will be created in (NOT NULL)
278 * @dentry: dentry to create (NOT NULL)
279 * @mask: request permission mask
280 * @mode: created file mode
281 *
282 * Returns: %0 else error code if error or permission denied
283 */
284 static int common_perm_create(const char *op, const struct path *dir,
285 struct dentry *dentry, u32 mask, umode_t mode)
286 {
287 struct path_cond cond = { current_fsuid(), mode };
288
289 if (!path_mediated_fs(dir->dentry))
290 return 0;
291
292 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
293 }
294
295 static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
296 {
297 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
298 }
299
300 static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
301 umode_t mode)
302 {
303 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
304 S_IFDIR);
305 }
306
307 static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
308 {
309 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
310 }
311
312 static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
313 umode_t mode, unsigned int dev)
314 {
315 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
316 }
317
318 static int apparmor_path_truncate(const struct path *path)
319 {
320 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
321 }
322
323 static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
324 const char *old_name)
325 {
326 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
327 S_IFLNK);
328 }
329
330 static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
331 struct dentry *new_dentry)
332 {
333 struct aa_label *label;
334 int error = 0;
335
336 if (!path_mediated_fs(old_dentry))
337 return 0;
338
339 label = begin_current_label_crit_section();
340 if (!unconfined(label))
341 error = aa_path_link(label, old_dentry, new_dir, new_dentry);
342 end_current_label_crit_section(label);
343
344 return error;
345 }
346
347 static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
348 const struct path *new_dir, struct dentry *new_dentry)
349 {
350 struct aa_label *label;
351 int error = 0;
352
353 if (!path_mediated_fs(old_dentry))
354 return 0;
355
356 label = begin_current_label_crit_section();
357 if (!unconfined(label)) {
358 struct path old_path = { .mnt = old_dir->mnt,
359 .dentry = old_dentry };
360 struct path new_path = { .mnt = new_dir->mnt,
361 .dentry = new_dentry };
362 struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
363 d_backing_inode(old_dentry)->i_mode
364 };
365
366 error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
367 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
368 AA_MAY_SETATTR | AA_MAY_DELETE,
369 &cond);
370 if (!error)
371 error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
372 0, MAY_WRITE | AA_MAY_SETATTR |
373 AA_MAY_CREATE, &cond);
374
375 }
376 end_current_label_crit_section(label);
377
378 return error;
379 }
380
381 static int apparmor_path_chmod(const struct path *path, umode_t mode)
382 {
383 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
384 }
385
386 static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
387 {
388 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
389 }
390
391 static int apparmor_inode_getattr(const struct path *path)
392 {
393 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
394 }
395
396 static int apparmor_file_open(struct file *file, const struct cred *cred)
397 {
398 struct aa_file_ctx *fctx = file_ctx(file);
399 struct aa_label *label;
400 int error = 0;
401
402 if (!path_mediated_fs(file->f_path.dentry))
403 return 0;
404
405 /* If in exec, permission is handled by bprm hooks.
406 * Cache permissions granted by the previous exec check, with
407 * implicit read and executable mmap which are required to
408 * actually execute the image.
409 */
410 if (current->in_execve) {
411 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
412 return 0;
413 }
414
415 label = aa_get_newest_cred_label(cred);
416 if (!unconfined(label)) {
417 struct inode *inode = file_inode(file);
418 struct path_cond cond = { inode->i_uid, inode->i_mode };
419
420 error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
421 aa_map_file_to_perms(file), &cond);
422 /* todo cache full allowed permissions set and state */
423 fctx->allow = aa_map_file_to_perms(file);
424 }
425 aa_put_label(label);
426
427 return error;
428 }
429
430 static int apparmor_file_alloc_security(struct file *file)
431 {
432 int error = 0;
433
434 /* freed by apparmor_file_free_security */
435 struct aa_label *label = begin_current_label_crit_section();
436 file->f_security = aa_alloc_file_ctx(label, GFP_KERNEL);
437 if (!file_ctx(file))
438 error = -ENOMEM;
439 end_current_label_crit_section(label);
440
441 return error;
442 }
443
444 static void apparmor_file_free_security(struct file *file)
445 {
446 aa_free_file_ctx(file_ctx(file));
447 }
448
449 static int common_file_perm(const char *op, struct file *file, u32 mask)
450 {
451 struct aa_label *label;
452 int error = 0;
453
454 /* don't reaudit files closed during inheritance */
455 if (file->f_path.dentry == aa_null.dentry)
456 return -EACCES;
457
458 label = __begin_current_label_crit_section();
459 error = aa_file_perm(op, label, file, mask);
460 __end_current_label_crit_section(label);
461
462 return error;
463 }
464
465 static int apparmor_file_receive(struct file *file)
466 {
467 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
468 }
469
470 static int apparmor_file_permission(struct file *file, int mask)
471 {
472 return common_file_perm(OP_FPERM, file, mask);
473 }
474
475 static int apparmor_file_lock(struct file *file, unsigned int cmd)
476 {
477 u32 mask = AA_MAY_LOCK;
478
479 if (cmd == F_WRLCK)
480 mask |= MAY_WRITE;
481
482 return common_file_perm(OP_FLOCK, file, mask);
483 }
484
485 static int common_mmap(const char *op, struct file *file, unsigned long prot,
486 unsigned long flags)
487 {
488 int mask = 0;
489
490 if (!file || !file_ctx(file))
491 return 0;
492
493 if (prot & PROT_READ)
494 mask |= MAY_READ;
495 /*
496 * Private mappings don't require write perms since they don't
497 * write back to the files
498 */
499 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
500 mask |= MAY_WRITE;
501 if (prot & PROT_EXEC)
502 mask |= AA_EXEC_MMAP;
503
504 return common_file_perm(op, file, mask);
505 }
506
507 static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
508 unsigned long prot, unsigned long flags)
509 {
510 return common_mmap(OP_FMMAP, file, prot, flags);
511 }
512
513 static int apparmor_file_mprotect(struct vm_area_struct *vma,
514 unsigned long reqprot, unsigned long prot)
515 {
516 return common_mmap(OP_FMPROT, vma->vm_file, prot,
517 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
518 }
519
520 static int apparmor_sb_mount(const char *dev_name, const struct path *path,
521 const char *type, unsigned long flags, void *data)
522 {
523 struct aa_label *label;
524 int error = 0;
525
526 /* Discard magic */
527 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
528 flags &= ~MS_MGC_MSK;
529
530 flags &= ~AA_MS_IGNORE_MASK;
531
532 label = __begin_current_label_crit_section();
533 if (!unconfined(label)) {
534 if (flags & MS_REMOUNT)
535 error = aa_remount(label, path, flags, data);
536 else if (flags & MS_BIND)
537 error = aa_bind_mount(label, path, dev_name, flags);
538 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
539 MS_UNBINDABLE))
540 error = aa_mount_change_type(label, path, flags);
541 else if (flags & MS_MOVE)
542 error = aa_move_mount(label, path, dev_name);
543 else
544 error = aa_new_mount(label, dev_name, path, type,
545 flags, data);
546 }
547 __end_current_label_crit_section(label);
548
549 return error;
550 }
551
552 static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
553 {
554 struct aa_label *label;
555 int error = 0;
556
557 label = __begin_current_label_crit_section();
558 if (!unconfined(label))
559 error = aa_umount(label, mnt, flags);
560 __end_current_label_crit_section(label);
561
562 return error;
563 }
564
565 static int apparmor_sb_pivotroot(const struct path *old_path,
566 const struct path *new_path)
567 {
568 struct aa_label *label;
569 int error = 0;
570
571 label = aa_get_current_label();
572 if (!unconfined(label))
573 error = aa_pivotroot(label, old_path, new_path);
574 aa_put_label(label);
575
576 return error;
577 }
578
579 static int apparmor_getprocattr(struct task_struct *task, char *name,
580 char **value)
581 {
582 int error = -ENOENT;
583 /* released below */
584 const struct cred *cred = get_task_cred(task);
585 struct aa_task_ctx *ctx = task_ctx(current);
586 struct aa_label *label = NULL;
587
588 if (strcmp(name, "current") == 0)
589 label = aa_get_newest_label(cred_label(cred));
590 else if (strcmp(name, "prev") == 0 && ctx->previous)
591 label = aa_get_newest_label(ctx->previous);
592 else if (strcmp(name, "exec") == 0 && ctx->onexec)
593 label = aa_get_newest_label(ctx->onexec);
594 else
595 error = -EINVAL;
596
597 if (label)
598 error = aa_getprocattr(label, value);
599
600 aa_put_label(label);
601 put_cred(cred);
602
603 return error;
604 }
605
606 static int apparmor_setprocattr(const char *name, void *value,
607 size_t size)
608 {
609 char *command, *largs = NULL, *args = value;
610 size_t arg_size;
611 int error;
612 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
613
614 if (size == 0)
615 return -EINVAL;
616
617 /* AppArmor requires that the buffer must be null terminated atm */
618 if (args[size - 1] != '\0') {
619 /* null terminate */
620 largs = args = kmalloc(size + 1, GFP_KERNEL);
621 if (!args)
622 return -ENOMEM;
623 memcpy(args, value, size);
624 args[size] = '\0';
625 }
626
627 error = -EINVAL;
628 args = strim(args);
629 command = strsep(&args, " ");
630 if (!args)
631 goto out;
632 args = skip_spaces(args);
633 if (!*args)
634 goto out;
635
636 arg_size = size - (args - (largs ? largs : (char *) value));
637 if (strcmp(name, "current") == 0) {
638 if (strcmp(command, "changehat") == 0) {
639 error = aa_setprocattr_changehat(args, arg_size,
640 AA_CHANGE_NOFLAGS);
641 } else if (strcmp(command, "permhat") == 0) {
642 error = aa_setprocattr_changehat(args, arg_size,
643 AA_CHANGE_TEST);
644 } else if (strcmp(command, "changeprofile") == 0) {
645 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
646 } else if (strcmp(command, "permprofile") == 0) {
647 error = aa_change_profile(args, AA_CHANGE_TEST);
648 } else if (strcmp(command, "stack") == 0) {
649 error = aa_change_profile(args, AA_CHANGE_STACK);
650 } else
651 goto fail;
652 } else if (strcmp(name, "exec") == 0) {
653 if (strcmp(command, "exec") == 0)
654 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
655 else if (strcmp(command, "stack") == 0)
656 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
657 AA_CHANGE_STACK));
658 else
659 goto fail;
660 } else
661 /* only support the "current" and "exec" process attributes */
662 goto fail;
663
664 if (!error)
665 error = size;
666 out:
667 kfree(largs);
668 return error;
669
670 fail:
671 aad(&sa)->label = begin_current_label_crit_section();
672 aad(&sa)->info = name;
673 aad(&sa)->error = error = -EINVAL;
674 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
675 end_current_label_crit_section(aad(&sa)->label);
676 goto out;
677 }
678
679 /**
680 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
681 * @bprm: binprm for the exec (NOT NULL)
682 */
683 static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
684 {
685 struct aa_label *label = aa_current_raw_label();
686 struct aa_label *new_label = cred_label(bprm->cred);
687
688 /* bail out if unconfined or not changing profile */
689 if ((new_label->proxy == label->proxy) ||
690 (unconfined(new_label)))
691 return;
692
693 aa_inherit_files(bprm->cred, current->files);
694
695 current->pdeath_signal = 0;
696
697 /* reset soft limits and set hard limits for the new label */
698 __aa_transition_rlimits(label, new_label);
699 }
700
701 /**
702 * apparmor_bprm_committed_cred - do cleanup after new creds committed
703 * @bprm: binprm for the exec (NOT NULL)
704 */
705 static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
706 {
707 /* clear out temporary/transitional state from the context */
708 aa_clear_task_ctx_trans(task_ctx(current));
709
710 return;
711 }
712
713 static int apparmor_task_setrlimit(struct task_struct *task,
714 unsigned int resource, struct rlimit *new_rlim)
715 {
716 struct aa_label *label = __begin_current_label_crit_section();
717 int error = 0;
718
719 if (!unconfined(label))
720 error = aa_task_setrlimit(label, task, resource, new_rlim);
721 __end_current_label_crit_section(label);
722
723 return error;
724 }
725
726 static int apparmor_task_kill(struct task_struct *target, struct siginfo *info,
727 int sig, const struct cred *cred)
728 {
729 struct aa_label *cl, *tl;
730 int error;
731
732 if (cred) {
733 /*
734 * Dealing with USB IO specific behavior
735 */
736 cl = aa_get_newest_cred_label(cred);
737 tl = aa_get_task_label(target);
738 error = aa_may_signal(cl, tl, sig);
739 aa_put_label(cl);
740 aa_put_label(tl);
741 return error;
742 }
743
744 cl = __begin_current_label_crit_section();
745 tl = aa_get_task_label(target);
746 error = aa_may_signal(cl, tl, sig);
747 aa_put_label(tl);
748 __end_current_label_crit_section(cl);
749
750 return error;
751 }
752
753 /**
754 * apparmor_sk_alloc_security - allocate and attach the sk_security field
755 */
756 static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
757 {
758 struct aa_sk_ctx *ctx;
759
760 ctx = kzalloc(sizeof(*ctx), flags);
761 if (!ctx)
762 return -ENOMEM;
763
764 SK_CTX(sk) = ctx;
765
766 return 0;
767 }
768
769 /**
770 * apparmor_sk_free_security - free the sk_security field
771 */
772 static void apparmor_sk_free_security(struct sock *sk)
773 {
774 struct aa_sk_ctx *ctx = SK_CTX(sk);
775
776 SK_CTX(sk) = NULL;
777 aa_put_label(ctx->label);
778 aa_put_label(ctx->peer);
779 kfree(ctx);
780 }
781
782 /**
783 * apparmor_clone_security - clone the sk_security field
784 */
785 static void apparmor_sk_clone_security(const struct sock *sk,
786 struct sock *newsk)
787 {
788 struct aa_sk_ctx *ctx = SK_CTX(sk);
789 struct aa_sk_ctx *new = SK_CTX(newsk);
790
791 new->label = aa_get_label(ctx->label);
792 new->peer = aa_get_label(ctx->peer);
793 }
794
795 /**
796 * apparmor_socket_create - check perms before creating a new socket
797 */
798 static int apparmor_socket_create(int family, int type, int protocol, int kern)
799 {
800 struct aa_label *label;
801 int error = 0;
802
803 AA_BUG(in_interrupt());
804
805 label = begin_current_label_crit_section();
806 if (!(kern || unconfined(label)))
807 error = af_select(family,
808 create_perm(label, family, type, protocol),
809 aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
810 family, type, protocol));
811 end_current_label_crit_section(label);
812
813 return error;
814 }
815
816 /**
817 * apparmor_socket_post_create - setup the per-socket security struct
818 *
819 * Note:
820 * - kernel sockets currently labeled unconfined but we may want to
821 * move to a special kernel label
822 * - socket may not have sk here if created with sock_create_lite or
823 * sock_alloc. These should be accept cases which will be handled in
824 * sock_graft.
825 */
826 static int apparmor_socket_post_create(struct socket *sock, int family,
827 int type, int protocol, int kern)
828 {
829 struct aa_label *label;
830
831 if (kern) {
832 struct aa_ns *ns = aa_get_current_ns();
833
834 label = aa_get_label(ns_unconfined(ns));
835 aa_put_ns(ns);
836 } else
837 label = aa_get_current_label();
838
839 if (sock->sk) {
840 struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
841
842 aa_put_label(ctx->label);
843 ctx->label = aa_get_label(label);
844 }
845 aa_put_label(label);
846
847 return 0;
848 }
849
850 /**
851 * apparmor_socket_bind - check perms before bind addr to socket
852 */
853 static int apparmor_socket_bind(struct socket *sock,
854 struct sockaddr *address, int addrlen)
855 {
856 AA_BUG(!sock);
857 AA_BUG(!sock->sk);
858 AA_BUG(!address);
859 AA_BUG(in_interrupt());
860
861 return af_select(sock->sk->sk_family,
862 bind_perm(sock, address, addrlen),
863 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
864 }
865
866 /**
867 * apparmor_socket_connect - check perms before connecting @sock to @address
868 */
869 static int apparmor_socket_connect(struct socket *sock,
870 struct sockaddr *address, int addrlen)
871 {
872 AA_BUG(!sock);
873 AA_BUG(!sock->sk);
874 AA_BUG(!address);
875 AA_BUG(in_interrupt());
876
877 return af_select(sock->sk->sk_family,
878 connect_perm(sock, address, addrlen),
879 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
880 }
881
882 /**
883 * apparmor_socket_list - check perms before allowing listen
884 */
885 static int apparmor_socket_listen(struct socket *sock, int backlog)
886 {
887 AA_BUG(!sock);
888 AA_BUG(!sock->sk);
889 AA_BUG(in_interrupt());
890
891 return af_select(sock->sk->sk_family,
892 listen_perm(sock, backlog),
893 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
894 }
895
896 /**
897 * apparmor_socket_accept - check perms before accepting a new connection.
898 *
899 * Note: while @newsock is created and has some information, the accept
900 * has not been done.
901 */
902 static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
903 {
904 AA_BUG(!sock);
905 AA_BUG(!sock->sk);
906 AA_BUG(!newsock);
907 AA_BUG(in_interrupt());
908
909 return af_select(sock->sk->sk_family,
910 accept_perm(sock, newsock),
911 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
912 }
913
914 static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
915 struct msghdr *msg, int size)
916 {
917 AA_BUG(!sock);
918 AA_BUG(!sock->sk);
919 AA_BUG(!msg);
920 AA_BUG(in_interrupt());
921
922 return af_select(sock->sk->sk_family,
923 msg_perm(op, request, sock, msg, size),
924 aa_sk_perm(op, request, sock->sk));
925 }
926
927 /**
928 * apparmor_socket_sendmsg - check perms before sending msg to another socket
929 */
930 static int apparmor_socket_sendmsg(struct socket *sock,
931 struct msghdr *msg, int size)
932 {
933 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
934 }
935
936 /**
937 * apparmor_socket_recvmsg - check perms before receiving a message
938 */
939 static int apparmor_socket_recvmsg(struct socket *sock,
940 struct msghdr *msg, int size, int flags)
941 {
942 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
943 }
944
945 /* revaliation, get/set attr, shutdown */
946 static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
947 {
948 AA_BUG(!sock);
949 AA_BUG(!sock->sk);
950 AA_BUG(in_interrupt());
951
952 return af_select(sock->sk->sk_family,
953 sock_perm(op, request, sock),
954 aa_sk_perm(op, request, sock->sk));
955 }
956
957 /**
958 * apparmor_socket_getsockname - check perms before getting the local address
959 */
960 static int apparmor_socket_getsockname(struct socket *sock)
961 {
962 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
963 }
964
965 /**
966 * apparmor_socket_getpeername - check perms before getting remote address
967 */
968 static int apparmor_socket_getpeername(struct socket *sock)
969 {
970 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
971 }
972
973 /* revaliation, get/set attr, opt */
974 static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
975 int level, int optname)
976 {
977 AA_BUG(!sock);
978 AA_BUG(!sock->sk);
979 AA_BUG(in_interrupt());
980
981 return af_select(sock->sk->sk_family,
982 opt_perm(op, request, sock, level, optname),
983 aa_sk_perm(op, request, sock->sk));
984 }
985
986 /**
987 * apparmor_getsockopt - check perms before getting socket options
988 */
989 static int apparmor_socket_getsockopt(struct socket *sock, int level,
990 int optname)
991 {
992 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
993 level, optname);
994 }
995
996 /**
997 * apparmor_setsockopt - check perms before setting socket options
998 */
999 static int apparmor_socket_setsockopt(struct socket *sock, int level,
1000 int optname)
1001 {
1002 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1003 level, optname);
1004 }
1005
1006 /**
1007 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1008 */
1009 static int apparmor_socket_shutdown(struct socket *sock, int how)
1010 {
1011 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1012 }
1013
1014 /**
1015 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1016 *
1017 * Note: can not sleep may be called with locks held
1018 *
1019 * dont want protocol specific in __skb_recv_datagram()
1020 * to deny an incoming connection socket_sock_rcv_skb()
1021 */
1022 static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1023 {
1024 return 0;
1025 }
1026
1027
1028 static struct aa_label *sk_peer_label(struct sock *sk)
1029 {
1030 struct aa_sk_ctx *ctx = SK_CTX(sk);
1031
1032 if (ctx->peer)
1033 return ctx->peer;
1034
1035 return ERR_PTR(-ENOPROTOOPT);
1036 }
1037
1038 /**
1039 * apparmor_socket_getpeersec_stream - get security context of peer
1040 *
1041 * Note: for tcp only valid if using ipsec or cipso on lan
1042 */
1043 static int apparmor_socket_getpeersec_stream(struct socket *sock,
1044 char __user *optval,
1045 int __user *optlen,
1046 unsigned int len)
1047 {
1048 char *name;
1049 int slen, error = 0;
1050 struct aa_label *label;
1051 struct aa_label *peer;
1052
1053 label = begin_current_label_crit_section();
1054 peer = sk_peer_label(sock->sk);
1055 if (IS_ERR(peer)) {
1056 error = PTR_ERR(peer);
1057 goto done;
1058 }
1059 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1060 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1061 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1062 /* don't include terminating \0 in slen, it breaks some apps */
1063 if (slen < 0) {
1064 error = -ENOMEM;
1065 } else {
1066 if (slen > len) {
1067 error = -ERANGE;
1068 } else if (copy_to_user(optval, name, slen)) {
1069 error = -EFAULT;
1070 goto out;
1071 }
1072 if (put_user(slen, optlen))
1073 error = -EFAULT;
1074 out:
1075 kfree(name);
1076
1077 }
1078
1079 done:
1080 end_current_label_crit_section(label);
1081
1082 return error;
1083 }
1084
1085 /**
1086 * apparmor_socket_getpeersec_dgram - get security label of packet
1087 * @sock: the peer socket
1088 * @skb: packet data
1089 * @secid: pointer to where to put the secid of the packet
1090 *
1091 * Sets the netlabel socket state on sk from parent
1092 */
1093 static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1094 struct sk_buff *skb, u32 *secid)
1095
1096 {
1097 /* TODO: requires secid support */
1098 return -ENOPROTOOPT;
1099 }
1100
1101 /**
1102 * apparmor_sock_graft - Initialize newly created socket
1103 * @sk: child sock
1104 * @parent: parent socket
1105 *
1106 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1107 * just set sk security information off of current creating process label
1108 * Labeling of sk for accept case - probably should be sock based
1109 * instead of task, because of the case where an implicitly labeled
1110 * socket is shared by different tasks.
1111 */
1112 static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1113 {
1114 struct aa_sk_ctx *ctx = SK_CTX(sk);
1115
1116 if (!ctx->label)
1117 ctx->label = aa_get_current_label();
1118 }
1119
1120 static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1121 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1122 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1123 LSM_HOOK_INIT(capget, apparmor_capget),
1124 LSM_HOOK_INIT(capable, apparmor_capable),
1125
1126 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1127 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1128 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1129
1130 LSM_HOOK_INIT(path_link, apparmor_path_link),
1131 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1132 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1133 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1134 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1135 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1136 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1137 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1138 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1139 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1140 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1141
1142 LSM_HOOK_INIT(file_open, apparmor_file_open),
1143 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1144 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1145 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1146 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1147 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1148 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1149 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1150
1151 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1152 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1153
1154 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1155 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1156 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1157
1158 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1159 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1160 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1161 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1162 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1163 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1164 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1165 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1166 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1167 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1168 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1169 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1170 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1171 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1172 LSM_HOOK_INIT(socket_getpeersec_stream,
1173 apparmor_socket_getpeersec_stream),
1174 LSM_HOOK_INIT(socket_getpeersec_dgram,
1175 apparmor_socket_getpeersec_dgram),
1176 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1177
1178 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1179 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1180 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1181 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1182
1183 LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
1184 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1185 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1186
1187 LSM_HOOK_INIT(task_free, apparmor_task_free),
1188 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1189 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1190 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1191 };
1192
1193 /*
1194 * AppArmor sysfs module parameters
1195 */
1196
1197 static int param_set_aabool(const char *val, const struct kernel_param *kp);
1198 static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1199 #define param_check_aabool param_check_bool
1200 static const struct kernel_param_ops param_ops_aabool = {
1201 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1202 .set = param_set_aabool,
1203 .get = param_get_aabool
1204 };
1205
1206 static int param_set_aauint(const char *val, const struct kernel_param *kp);
1207 static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1208 #define param_check_aauint param_check_uint
1209 static const struct kernel_param_ops param_ops_aauint = {
1210 .set = param_set_aauint,
1211 .get = param_get_aauint
1212 };
1213
1214 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1215 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1216 #define param_check_aalockpolicy param_check_bool
1217 static const struct kernel_param_ops param_ops_aalockpolicy = {
1218 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1219 .set = param_set_aalockpolicy,
1220 .get = param_get_aalockpolicy
1221 };
1222
1223 static int param_set_audit(const char *val, const struct kernel_param *kp);
1224 static int param_get_audit(char *buffer, const struct kernel_param *kp);
1225
1226 static int param_set_mode(const char *val, const struct kernel_param *kp);
1227 static int param_get_mode(char *buffer, const struct kernel_param *kp);
1228
1229 /* Flag values, also controllable via /sys/module/apparmor/parameters
1230 * We define special types as we want to do additional mediation.
1231 */
1232
1233 /* AppArmor global enforcement switch - complain, enforce, kill */
1234 enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1235 module_param_call(mode, param_set_mode, param_get_mode,
1236 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1237
1238 /* whether policy verification hashing is enabled */
1239 bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1240 #ifdef CONFIG_SECURITY_APPARMOR_HASH
1241 module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1242 #endif
1243
1244 /* Debug mode */
1245 bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1246 module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1247
1248 /* Audit mode */
1249 enum audit_mode aa_g_audit;
1250 module_param_call(audit, param_set_audit, param_get_audit,
1251 &aa_g_audit, S_IRUSR | S_IWUSR);
1252
1253 /* Determines if audit header is included in audited messages. This
1254 * provides more context if the audit daemon is not running
1255 */
1256 bool aa_g_audit_header = true;
1257 module_param_named(audit_header, aa_g_audit_header, aabool,
1258 S_IRUSR | S_IWUSR);
1259
1260 /* lock out loading/removal of policy
1261 * TODO: add in at boot loading of policy, which is the only way to
1262 * load policy, if lock_policy is set
1263 */
1264 bool aa_g_lock_policy;
1265 module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1266 S_IRUSR | S_IWUSR);
1267
1268 /* Syscall logging mode */
1269 bool aa_g_logsyscall;
1270 module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1271
1272 /* Maximum pathname length before accesses will start getting rejected */
1273 unsigned int aa_g_path_max = 2 * PATH_MAX;
1274 module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1275
1276 /* Determines how paranoid loading of policy is and how much verification
1277 * on the loaded policy is done.
1278 * DEPRECATED: read only as strict checking of load is always done now
1279 * that none root users (user namespaces) can load policy.
1280 */
1281 bool aa_g_paranoid_load = true;
1282 module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1283
1284 /* Boot time disable flag */
1285 static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
1286 module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
1287
1288 static int __init apparmor_enabled_setup(char *str)
1289 {
1290 unsigned long enabled;
1291 int error = kstrtoul(str, 0, &enabled);
1292 if (!error)
1293 apparmor_enabled = enabled ? 1 : 0;
1294 return 1;
1295 }
1296
1297 __setup("apparmor=", apparmor_enabled_setup);
1298
1299 /* set global flag turning off the ability to load policy */
1300 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1301 {
1302 if (!apparmor_enabled)
1303 return -EINVAL;
1304 if (apparmor_initialized && !policy_admin_capable(NULL))
1305 return -EPERM;
1306 return param_set_bool(val, kp);
1307 }
1308
1309 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1310 {
1311 if (!apparmor_enabled)
1312 return -EINVAL;
1313 if (apparmor_initialized && !policy_view_capable(NULL))
1314 return -EPERM;
1315 return param_get_bool(buffer, kp);
1316 }
1317
1318 static int param_set_aabool(const char *val, const struct kernel_param *kp)
1319 {
1320 if (!apparmor_enabled)
1321 return -EINVAL;
1322 if (apparmor_initialized && !policy_admin_capable(NULL))
1323 return -EPERM;
1324 return param_set_bool(val, kp);
1325 }
1326
1327 static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1328 {
1329 if (!apparmor_enabled)
1330 return -EINVAL;
1331 if (apparmor_initialized && !policy_view_capable(NULL))
1332 return -EPERM;
1333 return param_get_bool(buffer, kp);
1334 }
1335
1336 static int param_set_aauint(const char *val, const struct kernel_param *kp)
1337 {
1338 int error;
1339
1340 if (!apparmor_enabled)
1341 return -EINVAL;
1342 /* file is ro but enforce 2nd line check */
1343 if (apparmor_initialized)
1344 return -EPERM;
1345
1346 error = param_set_uint(val, kp);
1347 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1348
1349 return error;
1350 }
1351
1352 static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1353 {
1354 if (!apparmor_enabled)
1355 return -EINVAL;
1356 if (apparmor_initialized && !policy_view_capable(NULL))
1357 return -EPERM;
1358 return param_get_uint(buffer, kp);
1359 }
1360
1361 static int param_get_audit(char *buffer, const struct kernel_param *kp)
1362 {
1363 if (!apparmor_enabled)
1364 return -EINVAL;
1365 if (apparmor_initialized && !policy_view_capable(NULL))
1366 return -EPERM;
1367 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1368 }
1369
1370 static int param_set_audit(const char *val, const struct kernel_param *kp)
1371 {
1372 int i;
1373
1374 if (!apparmor_enabled)
1375 return -EINVAL;
1376 if (!val)
1377 return -EINVAL;
1378 if (apparmor_initialized && !policy_admin_capable(NULL))
1379 return -EPERM;
1380
1381 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
1382 if (strcmp(val, audit_mode_names[i]) == 0) {
1383 aa_g_audit = i;
1384 return 0;
1385 }
1386 }
1387
1388 return -EINVAL;
1389 }
1390
1391 static int param_get_mode(char *buffer, const struct kernel_param *kp)
1392 {
1393 if (!apparmor_enabled)
1394 return -EINVAL;
1395 if (apparmor_initialized && !policy_view_capable(NULL))
1396 return -EPERM;
1397
1398 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1399 }
1400
1401 static int param_set_mode(const char *val, const struct kernel_param *kp)
1402 {
1403 int i;
1404
1405 if (!apparmor_enabled)
1406 return -EINVAL;
1407 if (!val)
1408 return -EINVAL;
1409 if (apparmor_initialized && !policy_admin_capable(NULL))
1410 return -EPERM;
1411
1412 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
1413 if (strcmp(val, aa_profile_mode_names[i]) == 0) {
1414 aa_g_profile_mode = i;
1415 return 0;
1416 }
1417 }
1418
1419 return -EINVAL;
1420 }
1421
1422 /*
1423 * AppArmor init functions
1424 */
1425
1426 /**
1427 * set_init_ctx - set a task context and profile on the first task.
1428 *
1429 * TODO: allow setting an alternate profile than unconfined
1430 */
1431 static int __init set_init_ctx(void)
1432 {
1433 struct cred *cred = (struct cred *)current->real_cred;
1434 struct aa_task_ctx *ctx;
1435
1436 ctx = aa_alloc_task_ctx(GFP_KERNEL);
1437 if (!ctx)
1438 return -ENOMEM;
1439
1440 cred_label(cred) = aa_get_label(ns_unconfined(root_ns));
1441 task_ctx(current) = ctx;
1442
1443 return 0;
1444 }
1445
1446 static void destroy_buffers(void)
1447 {
1448 u32 i, j;
1449
1450 for_each_possible_cpu(i) {
1451 for_each_cpu_buffer(j) {
1452 kfree(per_cpu(aa_buffers, i).buf[j]);
1453 per_cpu(aa_buffers, i).buf[j] = NULL;
1454 }
1455 }
1456 }
1457
1458 static int __init alloc_buffers(void)
1459 {
1460 u32 i, j;
1461
1462 for_each_possible_cpu(i) {
1463 for_each_cpu_buffer(j) {
1464 char *buffer;
1465
1466 if (cpu_to_node(i) > num_online_nodes())
1467 /* fallback to kmalloc for offline nodes */
1468 buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
1469 else
1470 buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
1471 cpu_to_node(i));
1472 if (!buffer) {
1473 destroy_buffers();
1474 return -ENOMEM;
1475 }
1476 per_cpu(aa_buffers, i).buf[j] = buffer;
1477 }
1478 }
1479
1480 return 0;
1481 }
1482
1483 #ifdef CONFIG_SYSCTL
1484 static int apparmor_dointvec(struct ctl_table *table, int write,
1485 void __user *buffer, size_t *lenp, loff_t *ppos)
1486 {
1487 if (!policy_admin_capable(NULL))
1488 return -EPERM;
1489 if (!apparmor_enabled)
1490 return -EINVAL;
1491
1492 return proc_dointvec(table, write, buffer, lenp, ppos);
1493 }
1494
1495 static struct ctl_path apparmor_sysctl_path[] = {
1496 { .procname = "kernel", },
1497 { }
1498 };
1499
1500 static struct ctl_table apparmor_sysctl_table[] = {
1501 {
1502 .procname = "unprivileged_userns_apparmor_policy",
1503 .data = &unprivileged_userns_apparmor_policy,
1504 .maxlen = sizeof(int),
1505 .mode = 0600,
1506 .proc_handler = apparmor_dointvec,
1507 },
1508 { }
1509 };
1510
1511 static int __init apparmor_init_sysctl(void)
1512 {
1513 return register_sysctl_paths(apparmor_sysctl_path,
1514 apparmor_sysctl_table) ? 0 : -ENOMEM;
1515 }
1516 #else
1517 static inline int apparmor_init_sysctl(void)
1518 {
1519 return 0;
1520 }
1521 #endif /* CONFIG_SYSCTL */
1522
1523 static int __init apparmor_init(void)
1524 {
1525 int error;
1526
1527 if (!apparmor_enabled || !security_module_enable("apparmor")) {
1528 aa_info_message("AppArmor disabled by boot time parameter");
1529 apparmor_enabled = false;
1530 return 0;
1531 }
1532
1533 error = aa_setup_dfa_engine();
1534 if (error) {
1535 AA_ERROR("Unable to setup dfa engine\n");
1536 goto alloc_out;
1537 }
1538
1539 error = aa_alloc_root_ns();
1540 if (error) {
1541 AA_ERROR("Unable to allocate default profile namespace\n");
1542 goto alloc_out;
1543 }
1544
1545 error = apparmor_init_sysctl();
1546 if (error) {
1547 AA_ERROR("Unable to register sysctls\n");
1548 goto alloc_out;
1549
1550 }
1551
1552 error = alloc_buffers();
1553 if (error) {
1554 AA_ERROR("Unable to allocate work buffers\n");
1555 goto buffers_out;
1556 }
1557
1558 error = set_init_ctx();
1559 if (error) {
1560 AA_ERROR("Failed to set context on init task\n");
1561 aa_free_root_ns();
1562 goto buffers_out;
1563 }
1564 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1565 "apparmor");
1566
1567 /* Report that AppArmor successfully initialized */
1568 apparmor_initialized = 1;
1569 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1570 aa_info_message("AppArmor initialized: complain mode enabled");
1571 else if (aa_g_profile_mode == APPARMOR_KILL)
1572 aa_info_message("AppArmor initialized: kill mode enabled");
1573 else
1574 aa_info_message("AppArmor initialized");
1575
1576 return error;
1577
1578 buffers_out:
1579 destroy_buffers();
1580
1581 alloc_out:
1582 aa_destroy_aafs();
1583 aa_teardown_dfa_engine();
1584
1585 apparmor_enabled = false;
1586 return error;
1587 }
1588
1589 security_initcall(apparmor_init);