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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 <linux/kmemleak.h>
27 #include <net/sock.h>
28
29 #include "include/af_unix.h"
30 #include "include/apparmor.h"
31 #include "include/apparmorfs.h"
32 #include "include/audit.h"
33 #include "include/capability.h"
34 #include "include/context.h"
35 #include "include/file.h"
36 #include "include/ipc.h"
37 #include "include/net.h"
38 #include "include/path.h"
39 #include "include/label.h"
40 #include "include/policy.h"
41 #include "include/policy_ns.h"
42 #include "include/procattr.h"
43 #include "include/mount.h"
44
45 /* Flag indicating whether initialization completed */
46 int apparmor_initialized;
47
48 DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
49
50
51 /*
52 * LSM hook functions
53 */
54
55 /*
56 * free the associated aa_task_ctx and put its labels
57 */
58 static void apparmor_cred_free(struct cred *cred)
59 {
60 aa_free_task_context(cred_ctx(cred));
61 }
62
63 /*
64 * prepare new aa_task_ctx for modification by prepare_cred block
65 */
66 static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
67 gfp_t gfp)
68 {
69 aa_dup_task_context(cred_ctx(new), cred_ctx(old));
70 return 0;
71 }
72
73 /*
74 * transfer the apparmor data to a blank set of creds
75 */
76 static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
77 {
78 const struct aa_task_ctx *old_ctx = cred_ctx(old);
79 struct aa_task_ctx *new_ctx = cred_ctx(new);
80
81 aa_dup_task_context(new_ctx, old_ctx);
82 }
83
84 static int apparmor_ptrace_access_check(struct task_struct *child,
85 unsigned int mode)
86 {
87 struct aa_label *tracer, *tracee;
88 int error;
89
90 tracer = begin_current_label_crit_section();
91 tracee = aa_get_task_label(child);
92 error = aa_may_ptrace(tracer, tracee,
93 mode == PTRACE_MODE_READ ? AA_PTRACE_READ : AA_PTRACE_TRACE);
94 aa_put_label(tracee);
95 end_current_label_crit_section(tracer);
96
97 return error;
98 }
99
100 static int apparmor_ptrace_traceme(struct task_struct *parent)
101 {
102 struct aa_label *tracer, *tracee;
103 int error;
104
105 tracee = begin_current_label_crit_section();
106 tracer = aa_get_task_label(parent);
107 error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
108 aa_put_label(tracer);
109 end_current_label_crit_section(tracee);
110
111 return error;
112 }
113
114 /* Derived from security/commoncap.c:cap_capget */
115 static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
116 kernel_cap_t *inheritable, kernel_cap_t *permitted)
117 {
118 struct aa_label *label;
119 const struct cred *cred;
120
121 rcu_read_lock();
122 cred = __task_cred(target);
123 label = aa_get_newest_cred_label(cred);
124
125 /*
126 * cap_capget is stacked ahead of this and will
127 * initialize effective and permitted.
128 */
129 if (!unconfined(label)) {
130 struct aa_profile *profile;
131 struct label_it i;
132
133 label_for_each_confined(i, label, profile) {
134 if (COMPLAIN_MODE(profile))
135 continue;
136 *effective = cap_intersect(*effective,
137 profile->caps.allow);
138 *permitted = cap_intersect(*permitted,
139 profile->caps.allow);
140 }
141 }
142 rcu_read_unlock();
143 aa_put_label(label);
144
145 return 0;
146 }
147
148 static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
149 int cap, int audit)
150 {
151 struct aa_label *label;
152 int error = 0;
153
154 label = aa_get_newest_cred_label(cred);
155 if (!unconfined(label))
156 error = aa_capable(label, cap, audit);
157 aa_put_label(label);
158
159 return error;
160 }
161
162 /**
163 * common_perm - basic common permission check wrapper fn for paths
164 * @op: operation being checked
165 * @path: path to check permission of (NOT NULL)
166 * @mask: requested permissions mask
167 * @cond: conditional info for the permission request (NOT NULL)
168 *
169 * Returns: %0 else error code if error or permission denied
170 */
171 static int common_perm(const char *op, const struct path *path, u32 mask,
172 struct path_cond *cond)
173 {
174 struct aa_label *label;
175 int error = 0;
176
177 label = __begin_current_label_crit_section();
178 if (!unconfined(label))
179 error = aa_path_perm(op, label, path, 0, mask, cond);
180 __end_current_label_crit_section(label);
181
182 return error;
183 }
184
185 /**
186 * common_perm_cond - common permission wrapper around inode cond
187 * @op: operation being checked
188 * @path: location to check (NOT NULL)
189 * @mask: requested permissions mask
190 *
191 * Returns: %0 else error code if error or permission denied
192 */
193 static int common_perm_cond(const char *op, const struct path *path, u32 mask)
194 {
195 struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
196 d_backing_inode(path->dentry)->i_mode
197 };
198
199 if (!path_mediated_fs(path->dentry))
200 return 0;
201
202 return common_perm(op, path, mask, &cond);
203 }
204
205 /**
206 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
207 * @op: operation being checked
208 * @dir: directory of the dentry (NOT NULL)
209 * @dentry: dentry to check (NOT NULL)
210 * @mask: requested permissions mask
211 * @cond: conditional info for the permission request (NOT NULL)
212 *
213 * Returns: %0 else error code if error or permission denied
214 */
215 static int common_perm_dir_dentry(const char *op, const struct path *dir,
216 struct dentry *dentry, u32 mask,
217 struct path_cond *cond)
218 {
219 struct path path = { .mnt = dir->mnt, .dentry = dentry };
220
221 return common_perm(op, &path, mask, cond);
222 }
223
224 /**
225 * common_perm_rm - common permission wrapper for operations doing rm
226 * @op: operation being checked
227 * @dir: directory that the dentry is in (NOT NULL)
228 * @dentry: dentry being rm'd (NOT NULL)
229 * @mask: requested permission mask
230 *
231 * Returns: %0 else error code if error or permission denied
232 */
233 static int common_perm_rm(const char *op, const struct path *dir,
234 struct dentry *dentry, u32 mask)
235 {
236 struct inode *inode = d_backing_inode(dentry);
237 struct path_cond cond = { };
238
239 if (!inode || !path_mediated_fs(dentry))
240 return 0;
241
242 cond.uid = inode->i_uid;
243 cond.mode = inode->i_mode;
244
245 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
246 }
247
248 /**
249 * common_perm_create - common permission wrapper for operations doing create
250 * @op: operation being checked
251 * @dir: directory that dentry will be created in (NOT NULL)
252 * @dentry: dentry to create (NOT NULL)
253 * @mask: request permission mask
254 * @mode: created file mode
255 *
256 * Returns: %0 else error code if error or permission denied
257 */
258 static int common_perm_create(const char *op, const struct path *dir,
259 struct dentry *dentry, u32 mask, umode_t mode)
260 {
261 struct path_cond cond = { current_fsuid(), mode };
262
263 if (!path_mediated_fs(dir->dentry))
264 return 0;
265
266 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
267 }
268
269 static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
270 {
271 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
272 }
273
274 static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
275 umode_t mode)
276 {
277 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
278 S_IFDIR);
279 }
280
281 static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
282 {
283 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
284 }
285
286 static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
287 umode_t mode, unsigned int dev)
288 {
289 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
290 }
291
292 static int apparmor_path_truncate(const struct path *path)
293 {
294 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
295 }
296
297 static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
298 const char *old_name)
299 {
300 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
301 S_IFLNK);
302 }
303
304 static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
305 struct dentry *new_dentry)
306 {
307 struct aa_label *label;
308 int error = 0;
309
310 if (!path_mediated_fs(old_dentry))
311 return 0;
312
313 label = begin_current_label_crit_section();
314 if (!unconfined(label))
315 error = aa_path_link(label, old_dentry, new_dir, new_dentry);
316 end_current_label_crit_section(label);
317
318 return error;
319 }
320
321 static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
322 const struct path *new_dir, struct dentry *new_dentry)
323 {
324 struct aa_label *label;
325 int error = 0;
326
327 if (!path_mediated_fs(old_dentry))
328 return 0;
329
330 label = begin_current_label_crit_section();
331 if (!unconfined(label)) {
332 struct path old_path = { .mnt = old_dir->mnt,
333 .dentry = old_dentry };
334 struct path new_path = { .mnt = new_dir->mnt,
335 .dentry = new_dentry };
336 struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
337 d_backing_inode(old_dentry)->i_mode
338 };
339
340 error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
341 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
342 AA_MAY_SETATTR | AA_MAY_DELETE,
343 &cond);
344 if (!error)
345 error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
346 0, MAY_WRITE | AA_MAY_SETATTR |
347 AA_MAY_CREATE, &cond);
348
349 }
350 end_current_label_crit_section(label);
351
352 return error;
353 }
354
355 static int apparmor_path_chmod(const struct path *path, umode_t mode)
356 {
357 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
358 }
359
360 static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
361 {
362 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
363 }
364
365 static int apparmor_inode_getattr(const struct path *path)
366 {
367 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
368 }
369
370 static int apparmor_file_open(struct file *file, const struct cred *cred)
371 {
372 struct aa_file_ctx *fctx = file_ctx(file);
373 struct aa_label *label;
374 int error = 0;
375
376 if (!path_mediated_fs(file->f_path.dentry))
377 return 0;
378
379 /* If in exec, permission is handled by bprm hooks.
380 * Cache permissions granted by the previous exec check, with
381 * implicit read and executable mmap which are required to
382 * actually execute the image.
383 */
384 if (current->in_execve) {
385 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
386 return 0;
387 }
388
389 label = aa_get_newest_cred_label(cred);
390 if (!unconfined(label)) {
391 struct inode *inode = file_inode(file);
392 struct path_cond cond = { inode->i_uid, inode->i_mode };
393
394 error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
395 aa_map_file_to_perms(file), &cond);
396 /* todo cache full allowed permissions set and state */
397 fctx->allow = aa_map_file_to_perms(file);
398 }
399 aa_put_label(label);
400
401 return error;
402 }
403
404 static int apparmor_file_alloc_security(struct file *file)
405 {
406 int error = 0;
407
408 /* freed by apparmor_file_free_security */
409 struct aa_label *label = begin_current_label_crit_section();
410 file->f_security = aa_alloc_file_ctx(label, GFP_KERNEL);
411 if (!file_ctx(file))
412 error = -ENOMEM;
413 end_current_label_crit_section(label);
414
415 return error;
416 }
417
418 static void apparmor_file_free_security(struct file *file)
419 {
420 aa_free_file_ctx(file_ctx(file));
421 }
422
423 static int common_file_perm(const char *op, struct file *file, u32 mask)
424 {
425 struct aa_label *label;
426 int error = 0;
427
428 /* don't reaudit files closed during inheritance */
429 if (file->f_path.dentry == aa_null.dentry)
430 return -EACCES;
431
432 label = __begin_current_label_crit_section();
433 error = aa_file_perm(op, label, file, mask);
434 __end_current_label_crit_section(label);
435
436 return error;
437 }
438
439 static int apparmor_file_receive(struct file *file)
440 {
441 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
442 }
443
444 static int apparmor_file_permission(struct file *file, int mask)
445 {
446 return common_file_perm(OP_FPERM, file, mask);
447 }
448
449 static int apparmor_file_lock(struct file *file, unsigned int cmd)
450 {
451 u32 mask = AA_MAY_LOCK;
452
453 if (cmd == F_WRLCK)
454 mask |= MAY_WRITE;
455
456 return common_file_perm(OP_FLOCK, file, mask);
457 }
458
459 static int common_mmap(const char *op, struct file *file, unsigned long prot,
460 unsigned long flags)
461 {
462 int mask = 0;
463
464 if (!file || !file_ctx(file))
465 return 0;
466
467 if (prot & PROT_READ)
468 mask |= MAY_READ;
469 /*
470 * Private mappings don't require write perms since they don't
471 * write back to the files
472 */
473 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
474 mask |= MAY_WRITE;
475 if (prot & PROT_EXEC)
476 mask |= AA_EXEC_MMAP;
477
478 return common_file_perm(op, file, mask);
479 }
480
481 static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
482 unsigned long prot, unsigned long flags)
483 {
484 return common_mmap(OP_FMMAP, file, prot, flags);
485 }
486
487 static int apparmor_file_mprotect(struct vm_area_struct *vma,
488 unsigned long reqprot, unsigned long prot)
489 {
490 return common_mmap(OP_FMPROT, vma->vm_file, prot,
491 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
492 }
493
494 static int apparmor_sb_mount(const char *dev_name, const struct path *path,
495 const char *type, unsigned long flags, void *data)
496 {
497 struct aa_label *label;
498 int error = 0;
499
500 /* Discard magic */
501 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
502 flags &= ~MS_MGC_MSK;
503
504 flags &= ~AA_MS_IGNORE_MASK;
505
506 label = __begin_current_label_crit_section();
507 if (!unconfined(label)) {
508 if (flags & MS_REMOUNT)
509 error = aa_remount(label, path, flags, data);
510 else if (flags & MS_BIND)
511 error = aa_bind_mount(label, path, dev_name, flags);
512 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
513 MS_UNBINDABLE))
514 error = aa_mount_change_type(label, path, flags);
515 else if (flags & MS_MOVE)
516 error = aa_move_mount(label, path, dev_name);
517 else
518 error = aa_new_mount(label, dev_name, path, type,
519 flags, data);
520 }
521 __end_current_label_crit_section(label);
522
523 return error;
524 }
525
526 static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
527 {
528 struct aa_label *label;
529 int error = 0;
530
531 label = __begin_current_label_crit_section();
532 if (!unconfined(label))
533 error = aa_umount(label, mnt, flags);
534 __end_current_label_crit_section(label);
535
536 return error;
537 }
538
539 static int apparmor_sb_pivotroot(const struct path *old_path,
540 const struct path *new_path)
541 {
542 struct aa_label *label;
543 int error = 0;
544
545 label = aa_get_current_label();
546 if (!unconfined(label))
547 error = aa_pivotroot(label, old_path, new_path);
548 aa_put_label(label);
549
550 return error;
551 }
552
553 static int apparmor_getprocattr(struct task_struct *task, char *name,
554 char **value)
555 {
556 int error = -ENOENT;
557 /* released below */
558 const struct cred *cred = get_task_cred(task);
559 struct aa_task_ctx *ctx = cred_ctx(cred);
560 struct aa_label *label = NULL;
561
562 if (strcmp(name, "current") == 0)
563 label = aa_get_newest_label(ctx->label);
564 else if (strcmp(name, "prev") == 0 && ctx->previous)
565 label = aa_get_newest_label(ctx->previous);
566 else if (strcmp(name, "exec") == 0 && ctx->onexec)
567 label = aa_get_newest_label(ctx->onexec);
568 else
569 error = -EINVAL;
570
571 if (label)
572 error = aa_getprocattr(label, value);
573
574 aa_put_label(label);
575 put_cred(cred);
576
577 return error;
578 }
579
580 static int apparmor_setprocattr(const char *name, void *value,
581 size_t size)
582 {
583 char *command, *largs = NULL, *args = value;
584 size_t arg_size;
585 int error;
586 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
587
588 if (size == 0)
589 return -EINVAL;
590
591 /* AppArmor requires that the buffer must be null terminated atm */
592 if (args[size - 1] != '\0') {
593 /* null terminate */
594 largs = args = kmalloc(size + 1, GFP_KERNEL);
595 if (!args)
596 return -ENOMEM;
597 memcpy(args, value, size);
598 args[size] = '\0';
599 }
600
601 error = -EINVAL;
602 args = strim(args);
603 command = strsep(&args, " ");
604 if (!args)
605 goto out;
606 args = skip_spaces(args);
607 if (!*args)
608 goto out;
609
610 arg_size = size - (args - (largs ? largs : (char *) value));
611 if (strcmp(name, "current") == 0) {
612 if (strcmp(command, "changehat") == 0) {
613 error = aa_setprocattr_changehat(args, arg_size,
614 AA_CHANGE_NOFLAGS);
615 } else if (strcmp(command, "permhat") == 0) {
616 error = aa_setprocattr_changehat(args, arg_size,
617 AA_CHANGE_TEST);
618 } else if (strcmp(command, "changeprofile") == 0) {
619 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
620 } else if (strcmp(command, "permprofile") == 0) {
621 error = aa_change_profile(args, AA_CHANGE_TEST);
622 } else if (strcmp(command, "stack") == 0) {
623 error = aa_change_profile(args, AA_CHANGE_STACK);
624 } else
625 goto fail;
626 } else if (strcmp(name, "exec") == 0) {
627 if (strcmp(command, "exec") == 0)
628 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
629 else if (strcmp(command, "stack") == 0)
630 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
631 AA_CHANGE_STACK));
632 else
633 goto fail;
634 } else
635 /* only support the "current" and "exec" process attributes */
636 goto fail;
637
638 if (!error)
639 error = size;
640 out:
641 kfree(largs);
642 return error;
643
644 fail:
645 aad(&sa)->label = begin_current_label_crit_section();
646 aad(&sa)->info = name;
647 aad(&sa)->error = error = -EINVAL;
648 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
649 end_current_label_crit_section(aad(&sa)->label);
650 goto out;
651 }
652
653 /**
654 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
655 * @bprm: binprm for the exec (NOT NULL)
656 */
657 static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
658 {
659 struct aa_label *label = aa_current_raw_label();
660 struct aa_task_ctx *new_ctx = cred_ctx(bprm->cred);
661
662 /* bail out if unconfined or not changing profile */
663 if ((new_ctx->label->proxy == label->proxy) ||
664 (unconfined(new_ctx->label)))
665 return;
666
667 aa_inherit_files(bprm->cred, current->files);
668
669 current->pdeath_signal = 0;
670
671 /* reset soft limits and set hard limits for the new label */
672 __aa_transition_rlimits(label, new_ctx->label);
673 }
674
675 /**
676 * apparmor_bprm_committed_cred - do cleanup after new creds committed
677 * @bprm: binprm for the exec (NOT NULL)
678 */
679 static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
680 {
681 /* TODO: cleanup signals - ipc mediation */
682 return;
683 }
684
685 static int apparmor_task_setrlimit(struct task_struct *task,
686 unsigned int resource, struct rlimit *new_rlim)
687 {
688 struct aa_label *label = __begin_current_label_crit_section();
689 int error = 0;
690
691 if (!unconfined(label))
692 error = aa_task_setrlimit(label, task, resource, new_rlim);
693 __end_current_label_crit_section(label);
694
695 return error;
696 }
697
698 static int apparmor_task_kill(struct task_struct *target, struct siginfo *info,
699 int sig, u32 secid)
700 {
701 struct aa_label *cl, *tl;
702 int error;
703
704 if (secid)
705 /* TODO: after secid to label mapping is done.
706 * Dealing with USB IO specific behavior
707 */
708 return 0;
709 cl = __begin_current_label_crit_section();
710 tl = aa_get_task_label(target);
711 error = aa_may_signal(cl, tl, sig);
712 aa_put_label(tl);
713 __end_current_label_crit_section(cl);
714
715 return error;
716 }
717
718 /**
719 * apparmor_sk_alloc_security - allocate and attach the sk_security field
720 */
721 static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
722 {
723 struct aa_sk_ctx *ctx;
724
725 ctx = kzalloc(sizeof(*ctx), flags);
726 if (!ctx)
727 return -ENOMEM;
728
729 SK_CTX(sk) = ctx;
730
731 return 0;
732 }
733
734 /**
735 * apparmor_sk_free_security - free the sk_security field
736 */
737 static void apparmor_sk_free_security(struct sock *sk)
738 {
739 struct aa_sk_ctx *ctx = SK_CTX(sk);
740
741 SK_CTX(sk) = NULL;
742 aa_put_label(ctx->label);
743 aa_put_label(ctx->peer);
744 path_put(&ctx->path);
745 kfree(ctx);
746 }
747
748 /**
749 * apparmor_clone_security - clone the sk_security field
750 */
751 static void apparmor_sk_clone_security(const struct sock *sk,
752 struct sock *newsk)
753 {
754 struct aa_sk_ctx *ctx = SK_CTX(sk);
755 struct aa_sk_ctx *new = SK_CTX(newsk);
756
757 new->label = aa_get_label(ctx->label);
758 new->peer = aa_get_label(ctx->peer);
759 new->path = ctx->path;
760 path_get(&new->path);
761 }
762
763 static struct path *UNIX_FS_CONN_PATH(struct sock *sk, struct sock *newsk)
764 {
765 if (sk->sk_family == PF_UNIX && UNIX_FS(sk))
766 return &unix_sk(sk)->path;
767 else if (newsk->sk_family == PF_UNIX && UNIX_FS(newsk))
768 return &unix_sk(newsk)->path;
769 return NULL;
770 }
771
772 /**
773 * apparmor_unix_stream_connect - check perms before making unix domain conn
774 *
775 * peer is locked when this hook is called
776 */
777 static int apparmor_unix_stream_connect(struct sock *sk, struct sock *peer_sk,
778 struct sock *newsk)
779 {
780 struct aa_sk_ctx *sk_ctx = SK_CTX(sk);
781 struct aa_sk_ctx *peer_ctx = SK_CTX(peer_sk);
782 struct aa_sk_ctx *new_ctx = SK_CTX(newsk);
783 struct aa_label *label;
784 struct path *path;
785 int error;
786
787 label = __begin_current_label_crit_section();
788 error = aa_unix_peer_perm(label, OP_CONNECT,
789 (AA_MAY_CONNECT | AA_MAY_SEND | AA_MAY_RECEIVE),
790 sk, peer_sk, NULL);
791 if (!UNIX_FS(peer_sk)) {
792 last_error(error,
793 aa_unix_peer_perm(peer_ctx->label, OP_CONNECT,
794 (AA_MAY_ACCEPT | AA_MAY_SEND | AA_MAY_RECEIVE),
795 peer_sk, sk, label));
796 }
797 __end_current_label_crit_section(label);
798
799 if (error)
800 return error;
801
802 /* label newsk if it wasn't labeled in post_create. Normally this
803 * would be done in sock_graft, but because we are directly looking
804 * at the peer_sk to obtain peer_labeling for unix socks this
805 * does not work
806 */
807 if (!new_ctx->label)
808 new_ctx->label = aa_get_label(peer_ctx->label);
809
810 /* Cross reference the peer labels for SO_PEERSEC */
811 if (new_ctx->peer)
812 aa_put_label(new_ctx->peer);
813
814 if (sk_ctx->peer)
815 aa_put_label(sk_ctx->peer);
816
817 new_ctx->peer = aa_get_label(sk_ctx->label);
818 sk_ctx->peer = aa_get_label(peer_ctx->label);
819
820 path = UNIX_FS_CONN_PATH(sk, peer_sk);
821 if (path) {
822 new_ctx->path = *path;
823 sk_ctx->path = *path;
824 path_get(path);
825 path_get(path);
826 }
827 return 0;
828 }
829
830 /**
831 * apparmor_unix_may_send - check perms before conn or sending unix dgrams
832 *
833 * other is locked when this hook is called
834 *
835 * dgram connect calls may_send, peer setup but path not copied?????
836 */
837 static int apparmor_unix_may_send(struct socket *sock, struct socket *peer)
838 {
839 struct aa_sk_ctx *peer_ctx = SK_CTX(peer->sk);
840 struct aa_label *label;
841 int error;
842
843 label = __begin_current_label_crit_section();
844 error = xcheck(aa_unix_peer_perm(label, OP_SENDMSG, AA_MAY_SEND,
845 sock->sk, peer->sk, NULL),
846 aa_unix_peer_perm(peer_ctx->label, OP_SENDMSG,
847 AA_MAY_RECEIVE,
848 peer->sk, sock->sk, label));
849 __end_current_label_crit_section(label);
850
851 return error;
852 }
853
854 /**
855 * apparmor_socket_create - check perms before creating a new socket
856 */
857 static int apparmor_socket_create(int family, int type, int protocol, int kern)
858 {
859 struct aa_label *label;
860 int error = 0;
861
862 label = begin_current_label_crit_section();
863 if (!(kern || unconfined(label)))
864 error = aa_sock_create_perm(label, family, type, protocol);
865 end_current_label_crit_section(label);
866
867 return error;
868 }
869
870 /**
871 * apparmor_socket_post_create - setup the per-socket security struct
872 *
873 * Note:
874 * - kernel sockets currently labeled unconfined but we may want to
875 * move to a special kernel label
876 * - socket may not have sk here if created with sock_create_lite or
877 * sock_alloc. These should be accept cases which will be handled in
878 * sock_graft.
879 */
880 static int apparmor_socket_post_create(struct socket *sock, int family,
881 int type, int protocol, int kern)
882 {
883 struct aa_label *label;
884
885 if (kern) {
886 struct aa_ns *ns = aa_get_current_ns();
887
888 label = aa_get_label(ns_unconfined(ns));
889 aa_put_ns(ns);
890 } else
891 label = aa_get_current_label();
892
893 if (sock->sk) {
894 struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
895
896 aa_put_label(ctx->label);
897 ctx->label = aa_get_label(label);
898 }
899 aa_put_label(label);
900
901 return 0;
902 }
903
904 /**
905 * apparmor_socket_bind - check perms before bind addr to socket
906 */
907 static int apparmor_socket_bind(struct socket *sock,
908 struct sockaddr *address, int addrlen)
909 {
910 return aa_sock_bind_perm(sock, address, addrlen);
911 }
912
913 /**
914 * apparmor_socket_connect - check perms before connecting @sock to @address
915 */
916 static int apparmor_socket_connect(struct socket *sock,
917 struct sockaddr *address, int addrlen)
918 {
919 return aa_sock_connect_perm(sock, address, addrlen);
920 }
921
922 /**
923 * apparmor_socket_list - check perms before allowing listen
924 */
925 static int apparmor_socket_listen(struct socket *sock, int backlog)
926 {
927 return aa_sock_listen_perm(sock, backlog);
928 }
929
930 /**
931 * apparmor_socket_accept - check perms before accepting a new connection.
932 *
933 * Note: while @newsock is created and has some information, the accept
934 * has not been done.
935 */
936 static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
937 {
938 return aa_sock_accept_perm(sock, newsock);
939 }
940
941 /**
942 * apparmor_socket_sendmsg - check perms before sending msg to another socket
943 */
944 static int apparmor_socket_sendmsg(struct socket *sock,
945 struct msghdr *msg, int size)
946 {
947 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
948 }
949
950 /**
951 * apparmor_socket_recvmsg - check perms before receiving a message
952 */
953 static int apparmor_socket_recvmsg(struct socket *sock,
954 struct msghdr *msg, int size, int flags)
955 {
956 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
957 }
958
959 /**
960 * apparmor_socket_getsockname - check perms before getting the local address
961 */
962 static int apparmor_socket_getsockname(struct socket *sock)
963 {
964 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
965 }
966
967 /**
968 * apparmor_socket_getpeername - check perms before getting remote address
969 */
970 static int apparmor_socket_getpeername(struct socket *sock)
971 {
972 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
973 }
974
975 /**
976 * apparmor_getsockopt - check perms before getting socket options
977 */
978 static int apparmor_socket_getsockopt(struct socket *sock, int level,
979 int optname)
980 {
981 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
982 level, optname);
983 }
984
985 /**
986 * apparmor_setsockopt - check perms before setting socket options
987 */
988 static int apparmor_socket_setsockopt(struct socket *sock, int level,
989 int optname)
990 {
991 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
992 level, optname);
993 }
994
995 /**
996 * apparmor_socket_shutdown - check perms before shutting down @sock conn
997 */
998 static int apparmor_socket_shutdown(struct socket *sock, int how)
999 {
1000 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1001 }
1002
1003 /**
1004 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1005 *
1006 * Note: can not sleep may be called with locks held
1007 *
1008 * dont want protocol specific in __skb_recv_datagram()
1009 * to deny an incoming connection socket_sock_rcv_skb()
1010 */
1011 static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1012 {
1013 return 0;
1014 }
1015
1016
1017 static struct aa_label *sk_peer_label(struct sock *sk)
1018 {
1019 struct sock *peer_sk;
1020 struct aa_sk_ctx *ctx = SK_CTX(sk);
1021
1022 if (ctx->peer)
1023 return ctx->peer;
1024
1025 if (sk->sk_family != PF_UNIX)
1026 return ERR_PTR(-ENOPROTOOPT);
1027
1028 /* check for sockpair peering which does not go through
1029 * security_unix_stream_connect
1030 */
1031 peer_sk = unix_peer(sk);
1032 if (peer_sk) {
1033 ctx = SK_CTX(peer_sk);
1034 if (ctx->label)
1035 return ctx->label;
1036 }
1037
1038 return ERR_PTR(-ENOPROTOOPT);
1039 }
1040
1041 /**
1042 * apparmor_socket_getpeersec_stream - get security context of peer
1043 *
1044 * Note: for tcp only valid if using ipsec or cipso on lan
1045 */
1046 static int apparmor_socket_getpeersec_stream(struct socket *sock,
1047 char __user *optval,
1048 int __user *optlen,
1049 unsigned int len)
1050 {
1051 char *name;
1052 int slen, error = 0;
1053 struct aa_label *label;
1054 struct aa_label *peer;
1055
1056 label = begin_current_label_crit_section();
1057 peer = sk_peer_label(sock->sk);
1058 if (IS_ERR(peer)) {
1059 error = PTR_ERR(peer);
1060 goto done;
1061 }
1062 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1063 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1064 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1065 /* don't include terminating \0 in slen, it breaks some apps */
1066 if (slen < 0) {
1067 error = -ENOMEM;
1068 } else {
1069 if (slen > len) {
1070 error = -ERANGE;
1071 } else if (copy_to_user(optval, name, slen)) {
1072 error = -EFAULT;
1073 goto out;
1074 }
1075 if (put_user(slen, optlen))
1076 error = -EFAULT;
1077 out:
1078 kfree(name);
1079
1080 }
1081
1082 done:
1083 end_current_label_crit_section(label);
1084
1085 return error;
1086 }
1087
1088 /**
1089 * apparmor_socket_getpeersec_dgram - get security label of packet
1090 * @sock: the peer socket
1091 * @skb: packet data
1092 * @secid: pointer to where to put the secid of the packet
1093 *
1094 * Sets the netlabel socket state on sk from parent
1095 */
1096 static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1097 struct sk_buff *skb, u32 *secid)
1098
1099 {
1100 /* TODO: requires secid support */
1101 return -ENOPROTOOPT;
1102 }
1103
1104 /**
1105 * apparmor_sock_graft - Initialize newly created socket
1106 * @sk: child sock
1107 * @parent: parent socket
1108 *
1109 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1110 * just set sk security information off of current creating process label
1111 * Labeling of sk for accept case - probably should be sock based
1112 * instead of task, because of the case where an implicitly labeled
1113 * socket is shared by different tasks.
1114 */
1115 static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1116 {
1117 struct aa_sk_ctx *ctx = SK_CTX(sk);
1118
1119 if (!ctx->label)
1120 ctx->label = aa_get_current_label();
1121 }
1122
1123 struct lsm_blob_sizes apparmor_blob_sizes = {
1124 .lbs_cred = sizeof(struct aa_task_ctx),
1125 };
1126
1127 static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1128 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1129 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1130 LSM_HOOK_INIT(capget, apparmor_capget),
1131 LSM_HOOK_INIT(capable, apparmor_capable),
1132
1133 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1134 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1135 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1136
1137 LSM_HOOK_INIT(path_link, apparmor_path_link),
1138 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1139 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1140 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1141 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1142 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1143 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1144 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1145 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1146 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1147 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1148
1149 LSM_HOOK_INIT(file_open, apparmor_file_open),
1150 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1151 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1152 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1153 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1154 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1155 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1156 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1157
1158 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1159 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1160
1161 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1162 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1163 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1164
1165 LSM_HOOK_INIT(unix_stream_connect, apparmor_unix_stream_connect),
1166 LSM_HOOK_INIT(unix_may_send, apparmor_unix_may_send),
1167
1168 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1169 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1170 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1171 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1172 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1173 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1174 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1175 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1176 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1177 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1178 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1179 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1180 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1181 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1182 LSM_HOOK_INIT(socket_getpeersec_stream,
1183 apparmor_socket_getpeersec_stream),
1184 LSM_HOOK_INIT(socket_getpeersec_dgram,
1185 apparmor_socket_getpeersec_dgram),
1186 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1187
1188 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1189 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1190 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1191
1192 LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
1193 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1194 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1195
1196 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1197 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1198 };
1199
1200 /*
1201 * AppArmor sysfs module parameters
1202 */
1203
1204 static int param_set_aabool(const char *val, const struct kernel_param *kp);
1205 static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1206 #define param_check_aabool param_check_bool
1207 static const struct kernel_param_ops param_ops_aabool = {
1208 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1209 .set = param_set_aabool,
1210 .get = param_get_aabool
1211 };
1212
1213 static int param_set_aauint(const char *val, const struct kernel_param *kp);
1214 static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1215 #define param_check_aauint param_check_uint
1216 static const struct kernel_param_ops param_ops_aauint = {
1217 .set = param_set_aauint,
1218 .get = param_get_aauint
1219 };
1220
1221 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1222 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1223 #define param_check_aalockpolicy param_check_bool
1224 static const struct kernel_param_ops param_ops_aalockpolicy = {
1225 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1226 .set = param_set_aalockpolicy,
1227 .get = param_get_aalockpolicy
1228 };
1229
1230 static int param_set_audit(const char *val, const struct kernel_param *kp);
1231 static int param_get_audit(char *buffer, const struct kernel_param *kp);
1232
1233 static int param_set_mode(const char *val, const struct kernel_param *kp);
1234 static int param_get_mode(char *buffer, const struct kernel_param *kp);
1235
1236 /* Flag values, also controllable via /sys/module/apparmor/parameters
1237 * We define special types as we want to do additional mediation.
1238 */
1239
1240 /* AppArmor global enforcement switch - complain, enforce, kill */
1241 enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1242 module_param_call(mode, param_set_mode, param_get_mode,
1243 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1244
1245 /* whether policy verification hashing is enabled */
1246 bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1247 #ifdef CONFIG_SECURITY_APPARMOR_HASH
1248 module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1249 #endif
1250
1251 /* Debug mode */
1252 bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1253 module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1254
1255 /* Audit mode */
1256 enum audit_mode aa_g_audit;
1257 module_param_call(audit, param_set_audit, param_get_audit,
1258 &aa_g_audit, S_IRUSR | S_IWUSR);
1259
1260 /* Determines if audit header is included in audited messages. This
1261 * provides more context if the audit daemon is not running
1262 */
1263 bool aa_g_audit_header = true;
1264 module_param_named(audit_header, aa_g_audit_header, aabool,
1265 S_IRUSR | S_IWUSR);
1266
1267 /* lock out loading/removal of policy
1268 * TODO: add in at boot loading of policy, which is the only way to
1269 * load policy, if lock_policy is set
1270 */
1271 bool aa_g_lock_policy;
1272 module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1273 S_IRUSR | S_IWUSR);
1274
1275 /* Syscall logging mode */
1276 bool aa_g_logsyscall;
1277 module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1278
1279 /* Maximum pathname length before accesses will start getting rejected */
1280 unsigned int aa_g_path_max = 2 * PATH_MAX;
1281 module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1282
1283 /* Determines how paranoid loading of policy is and how much verification
1284 * on the loaded policy is done.
1285 * DEPRECATED: read only as strict checking of load is always done now
1286 * that none root users (user namespaces) can load policy.
1287 */
1288 bool aa_g_paranoid_load = true;
1289 module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1290
1291 /* Boot time disable flag */
1292 static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
1293 module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
1294
1295 static int __init apparmor_enabled_setup(char *str)
1296 {
1297 unsigned long enabled;
1298 int error = kstrtoul(str, 0, &enabled);
1299 if (!error)
1300 apparmor_enabled = enabled ? 1 : 0;
1301 return 1;
1302 }
1303
1304 __setup("apparmor=", apparmor_enabled_setup);
1305
1306 /* set global flag turning off the ability to load policy */
1307 static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1308 {
1309 if (!apparmor_enabled)
1310 return -EINVAL;
1311 if (apparmor_initialized && !policy_admin_capable(NULL))
1312 return -EPERM;
1313 return param_set_bool(val, kp);
1314 }
1315
1316 static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1317 {
1318 if (!apparmor_enabled)
1319 return -EINVAL;
1320 if (apparmor_initialized && !policy_view_capable(NULL))
1321 return -EPERM;
1322 return param_get_bool(buffer, kp);
1323 }
1324
1325 static int param_set_aabool(const char *val, const struct kernel_param *kp)
1326 {
1327 if (!apparmor_enabled)
1328 return -EINVAL;
1329 if (apparmor_initialized && !policy_admin_capable(NULL))
1330 return -EPERM;
1331 return param_set_bool(val, kp);
1332 }
1333
1334 static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1335 {
1336 if (!apparmor_enabled)
1337 return -EINVAL;
1338 if (apparmor_initialized && !policy_view_capable(NULL))
1339 return -EPERM;
1340 return param_get_bool(buffer, kp);
1341 }
1342
1343 static int param_set_aauint(const char *val, const struct kernel_param *kp)
1344 {
1345 int error;
1346
1347 if (!apparmor_enabled)
1348 return -EINVAL;
1349 /* file is ro but enforce 2nd line check */
1350 if (apparmor_initialized)
1351 return -EPERM;
1352
1353 error = param_set_uint(val, kp);
1354 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1355
1356 return error;
1357 }
1358
1359 static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1360 {
1361 if (!apparmor_enabled)
1362 return -EINVAL;
1363 if (apparmor_initialized && !policy_view_capable(NULL))
1364 return -EPERM;
1365 return param_get_uint(buffer, kp);
1366 }
1367
1368 static int param_get_audit(char *buffer, const struct kernel_param *kp)
1369 {
1370 if (!apparmor_enabled)
1371 return -EINVAL;
1372 if (apparmor_initialized && !policy_view_capable(NULL))
1373 return -EPERM;
1374 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1375 }
1376
1377 static int param_set_audit(const char *val, const struct kernel_param *kp)
1378 {
1379 int i;
1380
1381 if (!apparmor_enabled)
1382 return -EINVAL;
1383 if (!val)
1384 return -EINVAL;
1385 if (apparmor_initialized && !policy_admin_capable(NULL))
1386 return -EPERM;
1387
1388 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
1389 if (strcmp(val, audit_mode_names[i]) == 0) {
1390 aa_g_audit = i;
1391 return 0;
1392 }
1393 }
1394
1395 return -EINVAL;
1396 }
1397
1398 static int param_get_mode(char *buffer, const struct kernel_param *kp)
1399 {
1400 if (!apparmor_enabled)
1401 return -EINVAL;
1402 if (apparmor_initialized && !policy_view_capable(NULL))
1403 return -EPERM;
1404
1405 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1406 }
1407
1408 static int param_set_mode(const char *val, const struct kernel_param *kp)
1409 {
1410 int i;
1411
1412 if (!apparmor_enabled)
1413 return -EINVAL;
1414 if (!val)
1415 return -EINVAL;
1416 if (apparmor_initialized && !policy_admin_capable(NULL))
1417 return -EPERM;
1418
1419 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
1420 if (strcmp(val, aa_profile_mode_names[i]) == 0) {
1421 aa_g_profile_mode = i;
1422 return 0;
1423 }
1424 }
1425
1426 return -EINVAL;
1427 }
1428
1429 /*
1430 * AppArmor init functions
1431 */
1432
1433 /**
1434 * set_init_ctx - set a task context and profile on the first task.
1435 *
1436 * TODO: allow setting an alternate profile than unconfined
1437 */
1438 static int __init set_init_ctx(void)
1439 {
1440 struct cred *cred = (struct cred *)current->real_cred;
1441 struct aa_task_ctx *ctx;
1442
1443 lsm_early_cred(cred);
1444 ctx = apparmor_cred(cred);
1445
1446 ctx->label = aa_get_label(ns_unconfined(root_ns));
1447
1448 return 0;
1449 }
1450
1451 static void destroy_buffers(void)
1452 {
1453 u32 i, j;
1454
1455 for_each_possible_cpu(i) {
1456 for_each_cpu_buffer(j) {
1457 kfree(per_cpu(aa_buffers, i).buf[j]);
1458 per_cpu(aa_buffers, i).buf[j] = NULL;
1459 }
1460 }
1461 }
1462
1463 static int __init alloc_buffers(void)
1464 {
1465 u32 i, j;
1466
1467 for_each_possible_cpu(i) {
1468 for_each_cpu_buffer(j) {
1469 char *buffer;
1470
1471 if (cpu_to_node(i) > num_online_nodes())
1472 /* fallback to kmalloc for offline nodes */
1473 buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
1474 else
1475 buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
1476 cpu_to_node(i));
1477 if (!buffer) {
1478 destroy_buffers();
1479 return -ENOMEM;
1480 }
1481 per_cpu(aa_buffers, i).buf[j] = buffer;
1482 }
1483 }
1484
1485 return 0;
1486 }
1487
1488 #ifdef CONFIG_SYSCTL
1489 static int apparmor_dointvec(struct ctl_table *table, int write,
1490 void __user *buffer, size_t *lenp, loff_t *ppos)
1491 {
1492 if (!policy_admin_capable(NULL))
1493 return -EPERM;
1494 if (!apparmor_enabled)
1495 return -EINVAL;
1496
1497 return proc_dointvec(table, write, buffer, lenp, ppos);
1498 }
1499
1500 static struct ctl_path apparmor_sysctl_path[] = {
1501 { .procname = "kernel", },
1502 { }
1503 };
1504
1505 static struct ctl_table apparmor_sysctl_table[] = {
1506 {
1507 .procname = "unprivileged_userns_apparmor_policy",
1508 .data = &unprivileged_userns_apparmor_policy,
1509 .maxlen = sizeof(int),
1510 .mode = 0600,
1511 .proc_handler = apparmor_dointvec,
1512 },
1513 { }
1514 };
1515
1516 static int __init apparmor_init_sysctl(void)
1517 {
1518 return register_sysctl_paths(apparmor_sysctl_path,
1519 apparmor_sysctl_table) ? 0 : -ENOMEM;
1520 }
1521 #else
1522 static inline int apparmor_init_sysctl(void)
1523 {
1524 return 0;
1525 }
1526 #endif /* CONFIG_SYSCTL */
1527
1528 static int __init apparmor_init(void)
1529 {
1530 static int finish;
1531 int error;
1532
1533 if (!finish) {
1534 if (apparmor_enabled && security_module_enable("apparmor"))
1535 security_add_blobs(&apparmor_blob_sizes);
1536 else
1537 apparmor_enabled = false;
1538 finish = 1;
1539 return 0;
1540 }
1541
1542 if (!apparmor_enabled || !security_module_enable("apparmor")) {
1543 aa_info_message("AppArmor disabled by boot time parameter");
1544 apparmor_enabled = false;
1545 return 0;
1546 }
1547
1548 error = aa_setup_dfa_engine();
1549 if (error) {
1550 AA_ERROR("Unable to setup dfa engine\n");
1551 goto alloc_out;
1552 }
1553
1554 error = aa_alloc_root_ns();
1555 if (error) {
1556 AA_ERROR("Unable to allocate default profile namespace\n");
1557 goto alloc_out;
1558 }
1559
1560 error = apparmor_init_sysctl();
1561 if (error) {
1562 AA_ERROR("Unable to register sysctls\n");
1563 goto alloc_out;
1564
1565 }
1566
1567 error = alloc_buffers();
1568 if (error) {
1569 AA_ERROR("Unable to allocate work buffers\n");
1570 goto buffers_out;
1571 }
1572
1573 error = set_init_ctx();
1574 if (error) {
1575 AA_ERROR("Failed to set context on init task\n");
1576 aa_free_root_ns();
1577 goto buffers_out;
1578 }
1579 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1580 "apparmor");
1581
1582 /* Report that AppArmor successfully initialized */
1583 apparmor_initialized = 1;
1584 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1585 aa_info_message("AppArmor initialized: complain mode enabled");
1586 else if (aa_g_profile_mode == APPARMOR_KILL)
1587 aa_info_message("AppArmor initialized: kill mode enabled");
1588 else
1589 aa_info_message("AppArmor initialized");
1590
1591 return error;
1592
1593 buffers_out:
1594 destroy_buffers();
1595
1596 alloc_out:
1597 aa_destroy_aafs();
1598 aa_teardown_dfa_engine();
1599
1600 apparmor_enabled = false;
1601 return error;
1602 }
1603
1604 security_initcall(apparmor_init);