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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/security.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/context.h"
33#include "include/file.h"
34#include "include/ipc.h"
35#include "include/path.h"
36#include "include/policy.h"
37#include "include/procattr.h"
38
39/* Flag indicating whether initialization completed */
40int apparmor_initialized __initdata;
41
42/*
43 * LSM hook functions
44 */
45
46/*
47 * free the associated aa_task_cxt and put its profiles
48 */
49static void apparmor_cred_free(struct cred *cred)
50{
51 aa_free_task_context(cred_cxt(cred));
52 cred_cxt(cred) = NULL;
53}
54
55/*
56 * allocate the apparmor part of blank credentials
57 */
58static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
59{
60 /* freed by apparmor_cred_free */
61 struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
62 if (!cxt)
63 return -ENOMEM;
64
65 cred_cxt(cred) = cxt;
66 return 0;
67}
68
69/*
70 * prepare new aa_task_cxt for modification by prepare_cred block
71 */
72static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
73 gfp_t gfp)
74{
75 /* freed by apparmor_cred_free */
76 struct aa_task_cxt *cxt = aa_alloc_task_context(gfp);
77 if (!cxt)
78 return -ENOMEM;
79
80 aa_dup_task_context(cxt, cred_cxt(old));
81 cred_cxt(new) = cxt;
82 return 0;
83}
84
85/*
86 * transfer the apparmor data to a blank set of creds
87 */
88static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
89{
90 const struct aa_task_cxt *old_cxt = cred_cxt(old);
91 struct aa_task_cxt *new_cxt = cred_cxt(new);
92
93 aa_dup_task_context(new_cxt, old_cxt);
94}
95
96static int apparmor_ptrace_access_check(struct task_struct *child,
97 unsigned int mode)
98{
99 int error = cap_ptrace_access_check(child, mode);
100 if (error)
101 return error;
102
103 return aa_ptrace(current, child, mode);
104}
105
106static int apparmor_ptrace_traceme(struct task_struct *parent)
107{
108 int error = cap_ptrace_traceme(parent);
109 if (error)
110 return error;
111
112 return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
113}
114
115/* Derived from security/commoncap.c:cap_capget */
116static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
117 kernel_cap_t *inheritable, kernel_cap_t *permitted)
118{
119 struct aa_profile *profile;
120 const struct cred *cred;
121
122 rcu_read_lock();
123 cred = __task_cred(target);
124 profile = aa_cred_profile(cred);
125
126 *effective = cred->cap_effective;
127 *inheritable = cred->cap_inheritable;
128 *permitted = cred->cap_permitted;
129
130 if (!unconfined(profile) && !COMPLAIN_MODE(profile)) {
131 *effective = cap_intersect(*effective, profile->caps.allow);
132 *permitted = cap_intersect(*permitted, profile->caps.allow);
133 }
134 rcu_read_unlock();
135
136 return 0;
137}
138
139static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
140 int cap, int audit)
141{
142 struct aa_profile *profile;
143 /* cap_capable returns 0 on success, else -EPERM */
144 int error = cap_capable(cred, ns, cap, audit);
145 if (!error) {
146 profile = aa_cred_profile(cred);
147 if (!unconfined(profile))
148 error = aa_capable(profile, cap, audit);
149 }
150 return error;
151}
152
153/**
154 * common_perm - basic common permission check wrapper fn for paths
155 * @op: operation being checked
156 * @path: path to check permission of (NOT NULL)
157 * @mask: requested permissions mask
158 * @cond: conditional info for the permission request (NOT NULL)
159 *
160 * Returns: %0 else error code if error or permission denied
161 */
162static int common_perm(int op, struct path *path, u32 mask,
163 struct path_cond *cond)
164{
165 struct aa_profile *profile;
166 int error = 0;
167
168 profile = __aa_current_profile();
169 if (!unconfined(profile))
170 error = aa_path_perm(op, profile, path, 0, mask, cond);
171
172 return error;
173}
174
175/**
176 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
177 * @op: operation being checked
178 * @dir: directory of the dentry (NOT NULL)
179 * @dentry: dentry to check (NOT NULL)
180 * @mask: requested permissions mask
181 * @cond: conditional info for the permission request (NOT NULL)
182 *
183 * Returns: %0 else error code if error or permission denied
184 */
185static int common_perm_dir_dentry(int op, struct path *dir,
186 struct dentry *dentry, u32 mask,
187 struct path_cond *cond)
188{
189 struct path path = { dir->mnt, dentry };
190
191 return common_perm(op, &path, mask, cond);
192}
193
194/**
195 * common_perm_mnt_dentry - common permission wrapper when mnt, dentry
196 * @op: operation being checked
197 * @mnt: mount point of dentry (NOT NULL)
198 * @dentry: dentry to check (NOT NULL)
199 * @mask: requested permissions mask
200 *
201 * Returns: %0 else error code if error or permission denied
202 */
203static int common_perm_mnt_dentry(int op, struct vfsmount *mnt,
204 struct dentry *dentry, u32 mask)
205{
206 struct path path = { mnt, dentry };
207 struct path_cond cond = { dentry->d_inode->i_uid,
208 dentry->d_inode->i_mode
209 };
210
211 return common_perm(op, &path, mask, &cond);
212}
213
214/**
215 * common_perm_rm - common permission wrapper for operations doing rm
216 * @op: operation being checked
217 * @dir: directory that the dentry is in (NOT NULL)
218 * @dentry: dentry being rm'd (NOT NULL)
219 * @mask: requested permission mask
220 *
221 * Returns: %0 else error code if error or permission denied
222 */
223static int common_perm_rm(int op, struct path *dir,
224 struct dentry *dentry, u32 mask)
225{
226 struct inode *inode = dentry->d_inode;
227 struct path_cond cond = { };
228
229 if (!inode || !dir->mnt || !mediated_filesystem(inode))
230 return 0;
231
232 cond.uid = inode->i_uid;
233 cond.mode = inode->i_mode;
234
235 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
236}
237
238/**
239 * common_perm_create - common permission wrapper for operations doing create
240 * @op: operation being checked
241 * @dir: directory that dentry will be created in (NOT NULL)
242 * @dentry: dentry to create (NOT NULL)
243 * @mask: request permission mask
244 * @mode: created file mode
245 *
246 * Returns: %0 else error code if error or permission denied
247 */
248static int common_perm_create(int op, struct path *dir, struct dentry *dentry,
249 u32 mask, umode_t mode)
250{
251 struct path_cond cond = { current_fsuid(), mode };
252
253 if (!dir->mnt || !mediated_filesystem(dir->dentry->d_inode))
254 return 0;
255
256 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
257}
258
259static int apparmor_path_unlink(struct path *dir, struct dentry *dentry)
260{
261 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
262}
263
264static int apparmor_path_mkdir(struct path *dir, struct dentry *dentry,
265 umode_t mode)
266{
267 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
268 S_IFDIR);
269}
270
271static int apparmor_path_rmdir(struct path *dir, struct dentry *dentry)
272{
273 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
274}
275
276static int apparmor_path_mknod(struct path *dir, struct dentry *dentry,
277 umode_t mode, unsigned int dev)
278{
279 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
280}
281
282static int apparmor_path_truncate(struct path *path)
283{
284 struct path_cond cond = { path->dentry->d_inode->i_uid,
285 path->dentry->d_inode->i_mode
286 };
287
288 if (!path->mnt || !mediated_filesystem(path->dentry->d_inode))
289 return 0;
290
291 return common_perm(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE,
292 &cond);
293}
294
295static int apparmor_path_symlink(struct path *dir, struct dentry *dentry,
296 const char *old_name)
297{
298 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
299 S_IFLNK);
300}
301
302static int apparmor_path_link(struct dentry *old_dentry, struct path *new_dir,
303 struct dentry *new_dentry)
304{
305 struct aa_profile *profile;
306 int error = 0;
307
308 if (!mediated_filesystem(old_dentry->d_inode))
309 return 0;
310
311 profile = aa_current_profile();
312 if (!unconfined(profile))
313 error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
314 return error;
315}
316
317static int apparmor_path_rename(struct path *old_dir, struct dentry *old_dentry,
318 struct path *new_dir, struct dentry *new_dentry)
319{
320 struct aa_profile *profile;
321 int error = 0;
322
323 if (!mediated_filesystem(old_dentry->d_inode))
324 return 0;
325
326 profile = aa_current_profile();
327 if (!unconfined(profile)) {
328 struct path old_path = { old_dir->mnt, old_dentry };
329 struct path new_path = { new_dir->mnt, new_dentry };
330 struct path_cond cond = { old_dentry->d_inode->i_uid,
331 old_dentry->d_inode->i_mode
332 };
333
334 error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
335 MAY_READ | AA_MAY_META_READ | MAY_WRITE |
336 AA_MAY_META_WRITE | AA_MAY_DELETE,
337 &cond);
338 if (!error)
339 error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
340 0, MAY_WRITE | AA_MAY_META_WRITE |
341 AA_MAY_CREATE, &cond);
342
343 }
344 return error;
345}
346
347static int apparmor_path_chmod(struct path *path, umode_t mode)
348{
349 if (!mediated_filesystem(path->dentry->d_inode))
350 return 0;
351
352 return common_perm_mnt_dentry(OP_CHMOD, path->mnt, path->dentry, AA_MAY_CHMOD);
353}
354
355static int apparmor_path_chown(struct path *path, kuid_t uid, kgid_t gid)
356{
357 struct path_cond cond = { path->dentry->d_inode->i_uid,
358 path->dentry->d_inode->i_mode
359 };
360
361 if (!mediated_filesystem(path->dentry->d_inode))
362 return 0;
363
364 return common_perm(OP_CHOWN, path, AA_MAY_CHOWN, &cond);
365}
366
367static int apparmor_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
368{
369 if (!mediated_filesystem(dentry->d_inode))
370 return 0;
371
372 return common_perm_mnt_dentry(OP_GETATTR, mnt, dentry,
373 AA_MAY_META_READ);
374}
375
376static int apparmor_file_open(struct file *file, const struct cred *cred)
377{
378 struct aa_file_cxt *fcxt = file->f_security;
379 struct aa_profile *profile;
380 int error = 0;
381
382 if (!mediated_filesystem(file_inode(file)))
383 return 0;
384
385 /* If in exec, permission is handled by bprm hooks.
386 * Cache permissions granted by the previous exec check, with
387 * implicit read and executable mmap which are required to
388 * actually execute the image.
389 */
390 if (current->in_execve) {
391 fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
392 return 0;
393 }
394
395 profile = aa_cred_profile(cred);
396 if (!unconfined(profile)) {
397 struct inode *inode = file_inode(file);
398 struct path_cond cond = { inode->i_uid, inode->i_mode };
399
400 error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
401 aa_map_file_to_perms(file), &cond);
402 /* todo cache full allowed permissions set and state */
403 fcxt->allow = aa_map_file_to_perms(file);
404 }
405
406 return error;
407}
408
409static int apparmor_file_alloc_security(struct file *file)
410{
411 /* freed by apparmor_file_free_security */
412 file->f_security = aa_alloc_file_context(GFP_KERNEL);
413 if (!file->f_security)
414 return -ENOMEM;
415 return 0;
416
417}
418
419static void apparmor_file_free_security(struct file *file)
420{
421 struct aa_file_cxt *cxt = file->f_security;
422
423 aa_free_file_context(cxt);
424}
425
426static int common_file_perm(int op, struct file *file, u32 mask)
427{
428 struct aa_file_cxt *fcxt = file->f_security;
429 struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
430 int error = 0;
431
432 BUG_ON(!fprofile);
433
434 if (!file->f_path.mnt ||
435 !mediated_filesystem(file_inode(file)))
436 return 0;
437
438 profile = __aa_current_profile();
439
440 /* revalidate access, if task is unconfined, or the cached cred
441 * doesn't match or if the request is for more permissions than
442 * was granted.
443 *
444 * Note: the test for !unconfined(fprofile) is to handle file
445 * delegation from unconfined tasks
446 */
447 if (!unconfined(profile) && !unconfined(fprofile) &&
448 ((fprofile != profile) || (mask & ~fcxt->allow)))
449 error = aa_file_perm(op, profile, file, mask);
450
451 return error;
452}
453
454static int apparmor_file_permission(struct file *file, int mask)
455{
456 return common_file_perm(OP_FPERM, file, mask);
457}
458
459static int apparmor_file_lock(struct file *file, unsigned int cmd)
460{
461 u32 mask = AA_MAY_LOCK;
462
463 if (cmd == F_WRLCK)
464 mask |= MAY_WRITE;
465
466 return common_file_perm(OP_FLOCK, file, mask);
467}
468
469static int common_mmap(int op, struct file *file, unsigned long prot,
470 unsigned long flags)
471{
472 int mask = 0;
473
474 if (!file || !file->f_security)
475 return 0;
476
477 if (prot & PROT_READ)
478 mask |= MAY_READ;
479 /*
480 * Private mappings don't require write perms since they don't
481 * write back to the files
482 */
483 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
484 mask |= MAY_WRITE;
485 if (prot & PROT_EXEC)
486 mask |= AA_EXEC_MMAP;
487
488 return common_file_perm(op, file, mask);
489}
490
491static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
492 unsigned long prot, unsigned long flags)
493{
494 return common_mmap(OP_FMMAP, file, prot, flags);
495}
496
497static int apparmor_file_mprotect(struct vm_area_struct *vma,
498 unsigned long reqprot, unsigned long prot)
499{
500 return common_mmap(OP_FMPROT, vma->vm_file, prot,
501 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
502}
503
504static int apparmor_getprocattr(struct task_struct *task, char *name,
505 char **value)
506{
507 int error = -ENOENT;
508 /* released below */
509 const struct cred *cred = get_task_cred(task);
510 struct aa_task_cxt *cxt = cred_cxt(cred);
511 struct aa_profile *profile = NULL;
512
513 if (strcmp(name, "current") == 0)
514 profile = aa_get_newest_profile(cxt->profile);
515 else if (strcmp(name, "prev") == 0 && cxt->previous)
516 profile = aa_get_newest_profile(cxt->previous);
517 else if (strcmp(name, "exec") == 0 && cxt->onexec)
518 profile = aa_get_newest_profile(cxt->onexec);
519 else
520 error = -EINVAL;
521
522 if (profile)
523 error = aa_getprocattr(profile, value);
524
525 aa_put_profile(profile);
526 put_cred(cred);
527
528 return error;
529}
530
531static int apparmor_setprocattr(struct task_struct *task, char *name,
532 void *value, size_t size)
533{
534 struct common_audit_data sa;
535 struct apparmor_audit_data aad = {0,};
536 char *command, *args = value;
537 size_t arg_size;
538 int error;
539
540 if (size == 0)
541 return -EINVAL;
542 /* args points to a PAGE_SIZE buffer, AppArmor requires that
543 * the buffer must be null terminated or have size <= PAGE_SIZE -1
544 * so that AppArmor can null terminate them
545 */
546 if (args[size - 1] != '\0') {
547 if (size == PAGE_SIZE)
548 return -EINVAL;
549 args[size] = '\0';
550 }
551
552 /* task can only write its own attributes */
553 if (current != task)
554 return -EACCES;
555
556 args = value;
557 args = strim(args);
558 command = strsep(&args, " ");
559 if (!args)
560 return -EINVAL;
561 args = skip_spaces(args);
562 if (!*args)
563 return -EINVAL;
564
565 arg_size = size - (args - (char *) value);
566 if (strcmp(name, "current") == 0) {
567 if (strcmp(command, "changehat") == 0) {
568 error = aa_setprocattr_changehat(args, arg_size,
569 !AA_DO_TEST);
570 } else if (strcmp(command, "permhat") == 0) {
571 error = aa_setprocattr_changehat(args, arg_size,
572 AA_DO_TEST);
573 } else if (strcmp(command, "changeprofile") == 0) {
574 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
575 !AA_DO_TEST);
576 } else if (strcmp(command, "permprofile") == 0) {
577 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
578 AA_DO_TEST);
579 } else
580 goto fail;
581 } else if (strcmp(name, "exec") == 0) {
582 if (strcmp(command, "exec") == 0)
583 error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
584 !AA_DO_TEST);
585 else
586 goto fail;
587 } else
588 /* only support the "current" and "exec" process attributes */
589 return -EINVAL;
590
591 if (!error)
592 error = size;
593 return error;
594
595fail:
596 sa.type = LSM_AUDIT_DATA_NONE;
597 sa.aad = &aad;
598 aad.profile = aa_current_profile();
599 aad.op = OP_SETPROCATTR;
600 aad.info = name;
601 aad.error = -EINVAL;
602 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
603 return -EINVAL;
604}
605
606static int apparmor_task_setrlimit(struct task_struct *task,
607 unsigned int resource, struct rlimit *new_rlim)
608{
609 struct aa_profile *profile = __aa_current_profile();
610 int error = 0;
611
612 if (!unconfined(profile))
613 error = aa_task_setrlimit(profile, task, resource, new_rlim);
614
615 return error;
616}
617
618static struct security_operations apparmor_ops = {
619 .name = "apparmor",
620
621 .ptrace_access_check = apparmor_ptrace_access_check,
622 .ptrace_traceme = apparmor_ptrace_traceme,
623 .capget = apparmor_capget,
624 .capable = apparmor_capable,
625
626 .path_link = apparmor_path_link,
627 .path_unlink = apparmor_path_unlink,
628 .path_symlink = apparmor_path_symlink,
629 .path_mkdir = apparmor_path_mkdir,
630 .path_rmdir = apparmor_path_rmdir,
631 .path_mknod = apparmor_path_mknod,
632 .path_rename = apparmor_path_rename,
633 .path_chmod = apparmor_path_chmod,
634 .path_chown = apparmor_path_chown,
635 .path_truncate = apparmor_path_truncate,
636 .inode_getattr = apparmor_inode_getattr,
637
638 .file_open = apparmor_file_open,
639 .file_permission = apparmor_file_permission,
640 .file_alloc_security = apparmor_file_alloc_security,
641 .file_free_security = apparmor_file_free_security,
642 .mmap_file = apparmor_mmap_file,
643 .mmap_addr = cap_mmap_addr,
644 .file_mprotect = apparmor_file_mprotect,
645 .file_lock = apparmor_file_lock,
646
647 .getprocattr = apparmor_getprocattr,
648 .setprocattr = apparmor_setprocattr,
649
650 .cred_alloc_blank = apparmor_cred_alloc_blank,
651 .cred_free = apparmor_cred_free,
652 .cred_prepare = apparmor_cred_prepare,
653 .cred_transfer = apparmor_cred_transfer,
654
655 .bprm_set_creds = apparmor_bprm_set_creds,
656 .bprm_committing_creds = apparmor_bprm_committing_creds,
657 .bprm_committed_creds = apparmor_bprm_committed_creds,
658 .bprm_secureexec = apparmor_bprm_secureexec,
659
660 .task_setrlimit = apparmor_task_setrlimit,
661};
662
663/*
664 * AppArmor sysfs module parameters
665 */
666
667static int param_set_aabool(const char *val, const struct kernel_param *kp);
668static int param_get_aabool(char *buffer, const struct kernel_param *kp);
669#define param_check_aabool param_check_bool
670static struct kernel_param_ops param_ops_aabool = {
671 .flags = KERNEL_PARAM_FL_NOARG,
672 .set = param_set_aabool,
673 .get = param_get_aabool
674};
675
676static int param_set_aauint(const char *val, const struct kernel_param *kp);
677static int param_get_aauint(char *buffer, const struct kernel_param *kp);
678#define param_check_aauint param_check_uint
679static struct kernel_param_ops param_ops_aauint = {
680 .set = param_set_aauint,
681 .get = param_get_aauint
682};
683
684static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
685static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
686#define param_check_aalockpolicy param_check_bool
687static struct kernel_param_ops param_ops_aalockpolicy = {
688 .flags = KERNEL_PARAM_FL_NOARG,
689 .set = param_set_aalockpolicy,
690 .get = param_get_aalockpolicy
691};
692
693static int param_set_audit(const char *val, struct kernel_param *kp);
694static int param_get_audit(char *buffer, struct kernel_param *kp);
695
696static int param_set_mode(const char *val, struct kernel_param *kp);
697static int param_get_mode(char *buffer, struct kernel_param *kp);
698
699/* Flag values, also controllable via /sys/module/apparmor/parameters
700 * We define special types as we want to do additional mediation.
701 */
702
703/* AppArmor global enforcement switch - complain, enforce, kill */
704enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
705module_param_call(mode, param_set_mode, param_get_mode,
706 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
707
708/* Debug mode */
709bool aa_g_debug;
710module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
711
712/* Audit mode */
713enum audit_mode aa_g_audit;
714module_param_call(audit, param_set_audit, param_get_audit,
715 &aa_g_audit, S_IRUSR | S_IWUSR);
716
717/* Determines if audit header is included in audited messages. This
718 * provides more context if the audit daemon is not running
719 */
720bool aa_g_audit_header = 1;
721module_param_named(audit_header, aa_g_audit_header, aabool,
722 S_IRUSR | S_IWUSR);
723
724/* lock out loading/removal of policy
725 * TODO: add in at boot loading of policy, which is the only way to
726 * load policy, if lock_policy is set
727 */
728bool aa_g_lock_policy;
729module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
730 S_IRUSR | S_IWUSR);
731
732/* Syscall logging mode */
733bool aa_g_logsyscall;
734module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
735
736/* Maximum pathname length before accesses will start getting rejected */
737unsigned int aa_g_path_max = 2 * PATH_MAX;
738module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
739
740/* Determines how paranoid loading of policy is and how much verification
741 * on the loaded policy is done.
742 */
743bool aa_g_paranoid_load = 1;
744module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
745 S_IRUSR | S_IWUSR);
746
747/* Boot time disable flag */
748static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
749module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
750
751static int __init apparmor_enabled_setup(char *str)
752{
753 unsigned long enabled;
754 int error = kstrtoul(str, 0, &enabled);
755 if (!error)
756 apparmor_enabled = enabled ? 1 : 0;
757 return 1;
758}
759
760__setup("apparmor=", apparmor_enabled_setup);
761
762/* set global flag turning off the ability to load policy */
763static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
764{
765 if (!capable(CAP_MAC_ADMIN))
766 return -EPERM;
767 if (aa_g_lock_policy)
768 return -EACCES;
769 return param_set_bool(val, kp);
770}
771
772static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
773{
774 if (!capable(CAP_MAC_ADMIN))
775 return -EPERM;
776 return param_get_bool(buffer, kp);
777}
778
779static int param_set_aabool(const char *val, const struct kernel_param *kp)
780{
781 if (!capable(CAP_MAC_ADMIN))
782 return -EPERM;
783 return param_set_bool(val, kp);
784}
785
786static int param_get_aabool(char *buffer, const struct kernel_param *kp)
787{
788 if (!capable(CAP_MAC_ADMIN))
789 return -EPERM;
790 return param_get_bool(buffer, kp);
791}
792
793static int param_set_aauint(const char *val, const struct kernel_param *kp)
794{
795 if (!capable(CAP_MAC_ADMIN))
796 return -EPERM;
797 return param_set_uint(val, kp);
798}
799
800static int param_get_aauint(char *buffer, const struct kernel_param *kp)
801{
802 if (!capable(CAP_MAC_ADMIN))
803 return -EPERM;
804 return param_get_uint(buffer, kp);
805}
806
807static int param_get_audit(char *buffer, struct kernel_param *kp)
808{
809 if (!capable(CAP_MAC_ADMIN))
810 return -EPERM;
811
812 if (!apparmor_enabled)
813 return -EINVAL;
814
815 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
816}
817
818static int param_set_audit(const char *val, struct kernel_param *kp)
819{
820 int i;
821 if (!capable(CAP_MAC_ADMIN))
822 return -EPERM;
823
824 if (!apparmor_enabled)
825 return -EINVAL;
826
827 if (!val)
828 return -EINVAL;
829
830 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
831 if (strcmp(val, audit_mode_names[i]) == 0) {
832 aa_g_audit = i;
833 return 0;
834 }
835 }
836
837 return -EINVAL;
838}
839
840static int param_get_mode(char *buffer, struct kernel_param *kp)
841{
842 if (!capable(CAP_MAC_ADMIN))
843 return -EPERM;
844
845 if (!apparmor_enabled)
846 return -EINVAL;
847
848 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
849}
850
851static int param_set_mode(const char *val, struct kernel_param *kp)
852{
853 int i;
854 if (!capable(CAP_MAC_ADMIN))
855 return -EPERM;
856
857 if (!apparmor_enabled)
858 return -EINVAL;
859
860 if (!val)
861 return -EINVAL;
862
863 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
864 if (strcmp(val, aa_profile_mode_names[i]) == 0) {
865 aa_g_profile_mode = i;
866 return 0;
867 }
868 }
869
870 return -EINVAL;
871}
872
873/*
874 * AppArmor init functions
875 */
876
877/**
878 * set_init_cxt - set a task context and profile on the first task.
879 *
880 * TODO: allow setting an alternate profile than unconfined
881 */
882static int __init set_init_cxt(void)
883{
884 struct cred *cred = (struct cred *)current->real_cred;
885 struct aa_task_cxt *cxt;
886
887 cxt = aa_alloc_task_context(GFP_KERNEL);
888 if (!cxt)
889 return -ENOMEM;
890
891 cxt->profile = aa_get_profile(root_ns->unconfined);
892 cred_cxt(cred) = cxt;
893
894 return 0;
895}
896
897static int __init apparmor_init(void)
898{
899 int error;
900
901 if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
902 aa_info_message("AppArmor disabled by boot time parameter");
903 apparmor_enabled = 0;
904 return 0;
905 }
906
907 error = aa_alloc_root_ns();
908 if (error) {
909 AA_ERROR("Unable to allocate default profile namespace\n");
910 goto alloc_out;
911 }
912
913 error = set_init_cxt();
914 if (error) {
915 AA_ERROR("Failed to set context on init task\n");
916 goto register_security_out;
917 }
918
919 error = register_security(&apparmor_ops);
920 if (error) {
921 struct cred *cred = (struct cred *)current->real_cred;
922 aa_free_task_context(cred_cxt(cred));
923 cred_cxt(cred) = NULL;
924 AA_ERROR("Unable to register AppArmor\n");
925 goto register_security_out;
926 }
927
928 /* Report that AppArmor successfully initialized */
929 apparmor_initialized = 1;
930 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
931 aa_info_message("AppArmor initialized: complain mode enabled");
932 else if (aa_g_profile_mode == APPARMOR_KILL)
933 aa_info_message("AppArmor initialized: kill mode enabled");
934 else
935 aa_info_message("AppArmor initialized");
936
937 return error;
938
939register_security_out:
940 aa_free_root_ns();
941
942alloc_out:
943 aa_destroy_aafs();
944
945 apparmor_enabled = 0;
946 return error;
947}
948
949security_initcall(apparmor_init);
1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * AppArmor security module
4 *
5 * This file contains AppArmor LSM hooks.
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11#include <linux/lsm_hooks.h>
12#include <linux/moduleparam.h>
13#include <linux/mm.h>
14#include <linux/mman.h>
15#include <linux/mount.h>
16#include <linux/namei.h>
17#include <linux/ptrace.h>
18#include <linux/ctype.h>
19#include <linux/sysctl.h>
20#include <linux/audit.h>
21#include <linux/user_namespace.h>
22#include <linux/netfilter_ipv4.h>
23#include <linux/netfilter_ipv6.h>
24#include <linux/zlib.h>
25#include <net/sock.h>
26#include <uapi/linux/mount.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#include "include/secid.h"
43
44/* Flag indicating whether initialization completed */
45int apparmor_initialized;
46
47union aa_buffer {
48 struct list_head list;
49 char buffer[1];
50};
51
52#define RESERVE_COUNT 2
53static int reserve_count = RESERVE_COUNT;
54static int buffer_count;
55
56static LIST_HEAD(aa_global_buffers);
57static DEFINE_SPINLOCK(aa_buffers_lock);
58
59/*
60 * LSM hook functions
61 */
62
63/*
64 * put the associated labels
65 */
66static void apparmor_cred_free(struct cred *cred)
67{
68 aa_put_label(cred_label(cred));
69 set_cred_label(cred, NULL);
70}
71
72/*
73 * allocate the apparmor part of blank credentials
74 */
75static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
76{
77 set_cred_label(cred, NULL);
78 return 0;
79}
80
81/*
82 * prepare new cred label for modification by prepare_cred block
83 */
84static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
85 gfp_t gfp)
86{
87 set_cred_label(new, aa_get_newest_label(cred_label(old)));
88 return 0;
89}
90
91/*
92 * transfer the apparmor data to a blank set of creds
93 */
94static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
95{
96 set_cred_label(new, aa_get_newest_label(cred_label(old)));
97}
98
99static void apparmor_task_free(struct task_struct *task)
100{
101
102 aa_free_task_ctx(task_ctx(task));
103}
104
105static int apparmor_task_alloc(struct task_struct *task,
106 unsigned long clone_flags)
107{
108 struct aa_task_ctx *new = task_ctx(task);
109
110 aa_dup_task_ctx(new, task_ctx(current));
111
112 return 0;
113}
114
115static int apparmor_ptrace_access_check(struct task_struct *child,
116 unsigned int mode)
117{
118 struct aa_label *tracer, *tracee;
119 int error;
120
121 tracer = __begin_current_label_crit_section();
122 tracee = aa_get_task_label(child);
123 error = aa_may_ptrace(tracer, tracee,
124 (mode & PTRACE_MODE_READ) ? AA_PTRACE_READ
125 : AA_PTRACE_TRACE);
126 aa_put_label(tracee);
127 __end_current_label_crit_section(tracer);
128
129 return error;
130}
131
132static int apparmor_ptrace_traceme(struct task_struct *parent)
133{
134 struct aa_label *tracer, *tracee;
135 int error;
136
137 tracee = __begin_current_label_crit_section();
138 tracer = aa_get_task_label(parent);
139 error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
140 aa_put_label(tracer);
141 __end_current_label_crit_section(tracee);
142
143 return error;
144}
145
146/* Derived from security/commoncap.c:cap_capget */
147static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
148 kernel_cap_t *inheritable, kernel_cap_t *permitted)
149{
150 struct aa_label *label;
151 const struct cred *cred;
152
153 rcu_read_lock();
154 cred = __task_cred(target);
155 label = aa_get_newest_cred_label(cred);
156
157 /*
158 * cap_capget is stacked ahead of this and will
159 * initialize effective and permitted.
160 */
161 if (!unconfined(label)) {
162 struct aa_profile *profile;
163 struct label_it i;
164
165 label_for_each_confined(i, label, profile) {
166 if (COMPLAIN_MODE(profile))
167 continue;
168 *effective = cap_intersect(*effective,
169 profile->caps.allow);
170 *permitted = cap_intersect(*permitted,
171 profile->caps.allow);
172 }
173 }
174 rcu_read_unlock();
175 aa_put_label(label);
176
177 return 0;
178}
179
180static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
181 int cap, unsigned int opts)
182{
183 struct aa_label *label;
184 int error = 0;
185
186 label = aa_get_newest_cred_label(cred);
187 if (!unconfined(label))
188 error = aa_capable(label, cap, opts);
189 aa_put_label(label);
190
191 return error;
192}
193
194/**
195 * common_perm - basic common permission check wrapper fn for paths
196 * @op: operation being checked
197 * @path: path to check permission of (NOT NULL)
198 * @mask: requested permissions mask
199 * @cond: conditional info for the permission request (NOT NULL)
200 *
201 * Returns: %0 else error code if error or permission denied
202 */
203static int common_perm(const char *op, const struct path *path, u32 mask,
204 struct path_cond *cond)
205{
206 struct aa_label *label;
207 int error = 0;
208
209 label = __begin_current_label_crit_section();
210 if (!unconfined(label))
211 error = aa_path_perm(op, label, path, 0, mask, cond);
212 __end_current_label_crit_section(label);
213
214 return error;
215}
216
217/**
218 * common_perm_cond - common permission wrapper around inode cond
219 * @op: operation being checked
220 * @path: location to check (NOT NULL)
221 * @mask: requested permissions mask
222 *
223 * Returns: %0 else error code if error or permission denied
224 */
225static int common_perm_cond(const char *op, const struct path *path, u32 mask)
226{
227 struct user_namespace *mnt_userns = mnt_user_ns(path->mnt);
228 struct path_cond cond = {
229 i_uid_into_mnt(mnt_userns, d_backing_inode(path->dentry)),
230 d_backing_inode(path->dentry)->i_mode
231 };
232
233 if (!path_mediated_fs(path->dentry))
234 return 0;
235
236 return common_perm(op, path, mask, &cond);
237}
238
239/**
240 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
241 * @op: operation being checked
242 * @dir: directory of the dentry (NOT NULL)
243 * @dentry: dentry to check (NOT NULL)
244 * @mask: requested permissions mask
245 * @cond: conditional info for the permission request (NOT NULL)
246 *
247 * Returns: %0 else error code if error or permission denied
248 */
249static int common_perm_dir_dentry(const char *op, const struct path *dir,
250 struct dentry *dentry, u32 mask,
251 struct path_cond *cond)
252{
253 struct path path = { .mnt = dir->mnt, .dentry = dentry };
254
255 return common_perm(op, &path, mask, cond);
256}
257
258/**
259 * common_perm_rm - common permission wrapper for operations doing rm
260 * @op: operation being checked
261 * @dir: directory that the dentry is in (NOT NULL)
262 * @dentry: dentry being rm'd (NOT NULL)
263 * @mask: requested permission mask
264 *
265 * Returns: %0 else error code if error or permission denied
266 */
267static int common_perm_rm(const char *op, const struct path *dir,
268 struct dentry *dentry, u32 mask)
269{
270 struct inode *inode = d_backing_inode(dentry);
271 struct user_namespace *mnt_userns = mnt_user_ns(dir->mnt);
272 struct path_cond cond = { };
273
274 if (!inode || !path_mediated_fs(dentry))
275 return 0;
276
277 cond.uid = i_uid_into_mnt(mnt_userns, inode);
278 cond.mode = inode->i_mode;
279
280 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
281}
282
283/**
284 * common_perm_create - common permission wrapper for operations doing create
285 * @op: operation being checked
286 * @dir: directory that dentry will be created in (NOT NULL)
287 * @dentry: dentry to create (NOT NULL)
288 * @mask: request permission mask
289 * @mode: created file mode
290 *
291 * Returns: %0 else error code if error or permission denied
292 */
293static int common_perm_create(const char *op, const struct path *dir,
294 struct dentry *dentry, u32 mask, umode_t mode)
295{
296 struct path_cond cond = { current_fsuid(), mode };
297
298 if (!path_mediated_fs(dir->dentry))
299 return 0;
300
301 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
302}
303
304static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
305{
306 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
307}
308
309static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
310 umode_t mode)
311{
312 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
313 S_IFDIR);
314}
315
316static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
317{
318 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
319}
320
321static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
322 umode_t mode, unsigned int dev)
323{
324 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
325}
326
327static int apparmor_path_truncate(const struct path *path)
328{
329 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
330}
331
332static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
333 const char *old_name)
334{
335 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
336 S_IFLNK);
337}
338
339static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
340 struct dentry *new_dentry)
341{
342 struct aa_label *label;
343 int error = 0;
344
345 if (!path_mediated_fs(old_dentry))
346 return 0;
347
348 label = begin_current_label_crit_section();
349 if (!unconfined(label))
350 error = aa_path_link(label, old_dentry, new_dir, new_dentry);
351 end_current_label_crit_section(label);
352
353 return error;
354}
355
356static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
357 const struct path *new_dir, struct dentry *new_dentry)
358{
359 struct aa_label *label;
360 int error = 0;
361
362 if (!path_mediated_fs(old_dentry))
363 return 0;
364
365 label = begin_current_label_crit_section();
366 if (!unconfined(label)) {
367 struct user_namespace *mnt_userns = mnt_user_ns(old_dir->mnt);
368 struct path old_path = { .mnt = old_dir->mnt,
369 .dentry = old_dentry };
370 struct path new_path = { .mnt = new_dir->mnt,
371 .dentry = new_dentry };
372 struct path_cond cond = {
373 i_uid_into_mnt(mnt_userns, d_backing_inode(old_dentry)),
374 d_backing_inode(old_dentry)->i_mode
375 };
376
377 error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
378 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
379 AA_MAY_SETATTR | AA_MAY_DELETE,
380 &cond);
381 if (!error)
382 error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
383 0, MAY_WRITE | AA_MAY_SETATTR |
384 AA_MAY_CREATE, &cond);
385
386 }
387 end_current_label_crit_section(label);
388
389 return error;
390}
391
392static int apparmor_path_chmod(const struct path *path, umode_t mode)
393{
394 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
395}
396
397static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
398{
399 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
400}
401
402static int apparmor_inode_getattr(const struct path *path)
403{
404 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
405}
406
407static int apparmor_file_open(struct file *file)
408{
409 struct aa_file_ctx *fctx = file_ctx(file);
410 struct aa_label *label;
411 int error = 0;
412
413 if (!path_mediated_fs(file->f_path.dentry))
414 return 0;
415
416 /* If in exec, permission is handled by bprm hooks.
417 * Cache permissions granted by the previous exec check, with
418 * implicit read and executable mmap which are required to
419 * actually execute the image.
420 */
421 if (current->in_execve) {
422 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
423 return 0;
424 }
425
426 label = aa_get_newest_cred_label(file->f_cred);
427 if (!unconfined(label)) {
428 struct user_namespace *mnt_userns = file_mnt_user_ns(file);
429 struct inode *inode = file_inode(file);
430 struct path_cond cond = {
431 i_uid_into_mnt(mnt_userns, inode),
432 inode->i_mode
433 };
434
435 error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
436 aa_map_file_to_perms(file), &cond);
437 /* todo cache full allowed permissions set and state */
438 fctx->allow = aa_map_file_to_perms(file);
439 }
440 aa_put_label(label);
441
442 return error;
443}
444
445static int apparmor_file_alloc_security(struct file *file)
446{
447 struct aa_file_ctx *ctx = file_ctx(file);
448 struct aa_label *label = begin_current_label_crit_section();
449
450 spin_lock_init(&ctx->lock);
451 rcu_assign_pointer(ctx->label, aa_get_label(label));
452 end_current_label_crit_section(label);
453 return 0;
454}
455
456static void apparmor_file_free_security(struct file *file)
457{
458 struct aa_file_ctx *ctx = file_ctx(file);
459
460 if (ctx)
461 aa_put_label(rcu_access_pointer(ctx->label));
462}
463
464static int common_file_perm(const char *op, struct file *file, u32 mask,
465 bool in_atomic)
466{
467 struct aa_label *label;
468 int error = 0;
469
470 /* don't reaudit files closed during inheritance */
471 if (file->f_path.dentry == aa_null.dentry)
472 return -EACCES;
473
474 label = __begin_current_label_crit_section();
475 error = aa_file_perm(op, label, file, mask, in_atomic);
476 __end_current_label_crit_section(label);
477
478 return error;
479}
480
481static int apparmor_file_receive(struct file *file)
482{
483 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file),
484 false);
485}
486
487static int apparmor_file_permission(struct file *file, int mask)
488{
489 return common_file_perm(OP_FPERM, file, mask, false);
490}
491
492static int apparmor_file_lock(struct file *file, unsigned int cmd)
493{
494 u32 mask = AA_MAY_LOCK;
495
496 if (cmd == F_WRLCK)
497 mask |= MAY_WRITE;
498
499 return common_file_perm(OP_FLOCK, file, mask, false);
500}
501
502static int common_mmap(const char *op, struct file *file, unsigned long prot,
503 unsigned long flags, bool in_atomic)
504{
505 int mask = 0;
506
507 if (!file || !file_ctx(file))
508 return 0;
509
510 if (prot & PROT_READ)
511 mask |= MAY_READ;
512 /*
513 * Private mappings don't require write perms since they don't
514 * write back to the files
515 */
516 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
517 mask |= MAY_WRITE;
518 if (prot & PROT_EXEC)
519 mask |= AA_EXEC_MMAP;
520
521 return common_file_perm(op, file, mask, in_atomic);
522}
523
524static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
525 unsigned long prot, unsigned long flags)
526{
527 return common_mmap(OP_FMMAP, file, prot, flags, GFP_ATOMIC);
528}
529
530static int apparmor_file_mprotect(struct vm_area_struct *vma,
531 unsigned long reqprot, unsigned long prot)
532{
533 return common_mmap(OP_FMPROT, vma->vm_file, prot,
534 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0,
535 false);
536}
537
538static int apparmor_sb_mount(const char *dev_name, const struct path *path,
539 const char *type, unsigned long flags, void *data)
540{
541 struct aa_label *label;
542 int error = 0;
543
544 /* Discard magic */
545 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
546 flags &= ~MS_MGC_MSK;
547
548 flags &= ~AA_MS_IGNORE_MASK;
549
550 label = __begin_current_label_crit_section();
551 if (!unconfined(label)) {
552 if (flags & MS_REMOUNT)
553 error = aa_remount(label, path, flags, data);
554 else if (flags & MS_BIND)
555 error = aa_bind_mount(label, path, dev_name, flags);
556 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
557 MS_UNBINDABLE))
558 error = aa_mount_change_type(label, path, flags);
559 else if (flags & MS_MOVE)
560 error = aa_move_mount(label, path, dev_name);
561 else
562 error = aa_new_mount(label, dev_name, path, type,
563 flags, data);
564 }
565 __end_current_label_crit_section(label);
566
567 return error;
568}
569
570static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
571{
572 struct aa_label *label;
573 int error = 0;
574
575 label = __begin_current_label_crit_section();
576 if (!unconfined(label))
577 error = aa_umount(label, mnt, flags);
578 __end_current_label_crit_section(label);
579
580 return error;
581}
582
583static int apparmor_sb_pivotroot(const struct path *old_path,
584 const struct path *new_path)
585{
586 struct aa_label *label;
587 int error = 0;
588
589 label = aa_get_current_label();
590 if (!unconfined(label))
591 error = aa_pivotroot(label, old_path, new_path);
592 aa_put_label(label);
593
594 return error;
595}
596
597static int apparmor_getprocattr(struct task_struct *task, char *name,
598 char **value)
599{
600 int error = -ENOENT;
601 /* released below */
602 const struct cred *cred = get_task_cred(task);
603 struct aa_task_ctx *ctx = task_ctx(current);
604 struct aa_label *label = NULL;
605
606 if (strcmp(name, "current") == 0)
607 label = aa_get_newest_label(cred_label(cred));
608 else if (strcmp(name, "prev") == 0 && ctx->previous)
609 label = aa_get_newest_label(ctx->previous);
610 else if (strcmp(name, "exec") == 0 && ctx->onexec)
611 label = aa_get_newest_label(ctx->onexec);
612 else
613 error = -EINVAL;
614
615 if (label)
616 error = aa_getprocattr(label, value);
617
618 aa_put_label(label);
619 put_cred(cred);
620
621 return error;
622}
623
624static int apparmor_setprocattr(const char *name, void *value,
625 size_t size)
626{
627 char *command, *largs = NULL, *args = value;
628 size_t arg_size;
629 int error;
630 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
631
632 if (size == 0)
633 return -EINVAL;
634
635 /* AppArmor requires that the buffer must be null terminated atm */
636 if (args[size - 1] != '\0') {
637 /* null terminate */
638 largs = args = kmalloc(size + 1, GFP_KERNEL);
639 if (!args)
640 return -ENOMEM;
641 memcpy(args, value, size);
642 args[size] = '\0';
643 }
644
645 error = -EINVAL;
646 args = strim(args);
647 command = strsep(&args, " ");
648 if (!args)
649 goto out;
650 args = skip_spaces(args);
651 if (!*args)
652 goto out;
653
654 arg_size = size - (args - (largs ? largs : (char *) value));
655 if (strcmp(name, "current") == 0) {
656 if (strcmp(command, "changehat") == 0) {
657 error = aa_setprocattr_changehat(args, arg_size,
658 AA_CHANGE_NOFLAGS);
659 } else if (strcmp(command, "permhat") == 0) {
660 error = aa_setprocattr_changehat(args, arg_size,
661 AA_CHANGE_TEST);
662 } else if (strcmp(command, "changeprofile") == 0) {
663 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
664 } else if (strcmp(command, "permprofile") == 0) {
665 error = aa_change_profile(args, AA_CHANGE_TEST);
666 } else if (strcmp(command, "stack") == 0) {
667 error = aa_change_profile(args, AA_CHANGE_STACK);
668 } else
669 goto fail;
670 } else if (strcmp(name, "exec") == 0) {
671 if (strcmp(command, "exec") == 0)
672 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
673 else if (strcmp(command, "stack") == 0)
674 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
675 AA_CHANGE_STACK));
676 else
677 goto fail;
678 } else
679 /* only support the "current" and "exec" process attributes */
680 goto fail;
681
682 if (!error)
683 error = size;
684out:
685 kfree(largs);
686 return error;
687
688fail:
689 aad(&sa)->label = begin_current_label_crit_section();
690 aad(&sa)->info = name;
691 aad(&sa)->error = error = -EINVAL;
692 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
693 end_current_label_crit_section(aad(&sa)->label);
694 goto out;
695}
696
697/**
698 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
699 * @bprm: binprm for the exec (NOT NULL)
700 */
701static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
702{
703 struct aa_label *label = aa_current_raw_label();
704 struct aa_label *new_label = cred_label(bprm->cred);
705
706 /* bail out if unconfined or not changing profile */
707 if ((new_label->proxy == label->proxy) ||
708 (unconfined(new_label)))
709 return;
710
711 aa_inherit_files(bprm->cred, current->files);
712
713 current->pdeath_signal = 0;
714
715 /* reset soft limits and set hard limits for the new label */
716 __aa_transition_rlimits(label, new_label);
717}
718
719/**
720 * apparmor_bprm_committed_cred - do cleanup after new creds committed
721 * @bprm: binprm for the exec (NOT NULL)
722 */
723static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
724{
725 /* clear out temporary/transitional state from the context */
726 aa_clear_task_ctx_trans(task_ctx(current));
727
728 return;
729}
730
731static void apparmor_task_getsecid(struct task_struct *p, u32 *secid)
732{
733 struct aa_label *label = aa_get_task_label(p);
734 *secid = label->secid;
735 aa_put_label(label);
736}
737
738static int apparmor_task_setrlimit(struct task_struct *task,
739 unsigned int resource, struct rlimit *new_rlim)
740{
741 struct aa_label *label = __begin_current_label_crit_section();
742 int error = 0;
743
744 if (!unconfined(label))
745 error = aa_task_setrlimit(label, task, resource, new_rlim);
746 __end_current_label_crit_section(label);
747
748 return error;
749}
750
751static int apparmor_task_kill(struct task_struct *target, struct kernel_siginfo *info,
752 int sig, const struct cred *cred)
753{
754 struct aa_label *cl, *tl;
755 int error;
756
757 if (cred) {
758 /*
759 * Dealing with USB IO specific behavior
760 */
761 cl = aa_get_newest_cred_label(cred);
762 tl = aa_get_task_label(target);
763 error = aa_may_signal(cl, tl, sig);
764 aa_put_label(cl);
765 aa_put_label(tl);
766 return error;
767 }
768
769 cl = __begin_current_label_crit_section();
770 tl = aa_get_task_label(target);
771 error = aa_may_signal(cl, tl, sig);
772 aa_put_label(tl);
773 __end_current_label_crit_section(cl);
774
775 return error;
776}
777
778/**
779 * apparmor_sk_alloc_security - allocate and attach the sk_security field
780 */
781static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
782{
783 struct aa_sk_ctx *ctx;
784
785 ctx = kzalloc(sizeof(*ctx), flags);
786 if (!ctx)
787 return -ENOMEM;
788
789 SK_CTX(sk) = ctx;
790
791 return 0;
792}
793
794/**
795 * apparmor_sk_free_security - free the sk_security field
796 */
797static void apparmor_sk_free_security(struct sock *sk)
798{
799 struct aa_sk_ctx *ctx = SK_CTX(sk);
800
801 SK_CTX(sk) = NULL;
802 aa_put_label(ctx->label);
803 aa_put_label(ctx->peer);
804 kfree(ctx);
805}
806
807/**
808 * apparmor_clone_security - clone the sk_security field
809 */
810static void apparmor_sk_clone_security(const struct sock *sk,
811 struct sock *newsk)
812{
813 struct aa_sk_ctx *ctx = SK_CTX(sk);
814 struct aa_sk_ctx *new = SK_CTX(newsk);
815
816 if (new->label)
817 aa_put_label(new->label);
818 new->label = aa_get_label(ctx->label);
819
820 if (new->peer)
821 aa_put_label(new->peer);
822 new->peer = aa_get_label(ctx->peer);
823}
824
825/**
826 * apparmor_socket_create - check perms before creating a new socket
827 */
828static int apparmor_socket_create(int family, int type, int protocol, int kern)
829{
830 struct aa_label *label;
831 int error = 0;
832
833 AA_BUG(in_interrupt());
834
835 label = begin_current_label_crit_section();
836 if (!(kern || unconfined(label)))
837 error = af_select(family,
838 create_perm(label, family, type, protocol),
839 aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
840 family, type, protocol));
841 end_current_label_crit_section(label);
842
843 return error;
844}
845
846/**
847 * apparmor_socket_post_create - setup the per-socket security struct
848 *
849 * Note:
850 * - kernel sockets currently labeled unconfined but we may want to
851 * move to a special kernel label
852 * - socket may not have sk here if created with sock_create_lite or
853 * sock_alloc. These should be accept cases which will be handled in
854 * sock_graft.
855 */
856static int apparmor_socket_post_create(struct socket *sock, int family,
857 int type, int protocol, int kern)
858{
859 struct aa_label *label;
860
861 if (kern) {
862 struct aa_ns *ns = aa_get_current_ns();
863
864 label = aa_get_label(ns_unconfined(ns));
865 aa_put_ns(ns);
866 } else
867 label = aa_get_current_label();
868
869 if (sock->sk) {
870 struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
871
872 aa_put_label(ctx->label);
873 ctx->label = aa_get_label(label);
874 }
875 aa_put_label(label);
876
877 return 0;
878}
879
880/**
881 * apparmor_socket_bind - check perms before bind addr to socket
882 */
883static int apparmor_socket_bind(struct socket *sock,
884 struct sockaddr *address, int addrlen)
885{
886 AA_BUG(!sock);
887 AA_BUG(!sock->sk);
888 AA_BUG(!address);
889 AA_BUG(in_interrupt());
890
891 return af_select(sock->sk->sk_family,
892 bind_perm(sock, address, addrlen),
893 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
894}
895
896/**
897 * apparmor_socket_connect - check perms before connecting @sock to @address
898 */
899static int apparmor_socket_connect(struct socket *sock,
900 struct sockaddr *address, int addrlen)
901{
902 AA_BUG(!sock);
903 AA_BUG(!sock->sk);
904 AA_BUG(!address);
905 AA_BUG(in_interrupt());
906
907 return af_select(sock->sk->sk_family,
908 connect_perm(sock, address, addrlen),
909 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
910}
911
912/**
913 * apparmor_socket_list - check perms before allowing listen
914 */
915static int apparmor_socket_listen(struct socket *sock, int backlog)
916{
917 AA_BUG(!sock);
918 AA_BUG(!sock->sk);
919 AA_BUG(in_interrupt());
920
921 return af_select(sock->sk->sk_family,
922 listen_perm(sock, backlog),
923 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
924}
925
926/**
927 * apparmor_socket_accept - check perms before accepting a new connection.
928 *
929 * Note: while @newsock is created and has some information, the accept
930 * has not been done.
931 */
932static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
933{
934 AA_BUG(!sock);
935 AA_BUG(!sock->sk);
936 AA_BUG(!newsock);
937 AA_BUG(in_interrupt());
938
939 return af_select(sock->sk->sk_family,
940 accept_perm(sock, newsock),
941 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
942}
943
944static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
945 struct msghdr *msg, int size)
946{
947 AA_BUG(!sock);
948 AA_BUG(!sock->sk);
949 AA_BUG(!msg);
950 AA_BUG(in_interrupt());
951
952 return af_select(sock->sk->sk_family,
953 msg_perm(op, request, sock, msg, size),
954 aa_sk_perm(op, request, sock->sk));
955}
956
957/**
958 * apparmor_socket_sendmsg - check perms before sending msg to another socket
959 */
960static int apparmor_socket_sendmsg(struct socket *sock,
961 struct msghdr *msg, int size)
962{
963 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
964}
965
966/**
967 * apparmor_socket_recvmsg - check perms before receiving a message
968 */
969static int apparmor_socket_recvmsg(struct socket *sock,
970 struct msghdr *msg, int size, int flags)
971{
972 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
973}
974
975/* revaliation, get/set attr, shutdown */
976static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
977{
978 AA_BUG(!sock);
979 AA_BUG(!sock->sk);
980 AA_BUG(in_interrupt());
981
982 return af_select(sock->sk->sk_family,
983 sock_perm(op, request, sock),
984 aa_sk_perm(op, request, sock->sk));
985}
986
987/**
988 * apparmor_socket_getsockname - check perms before getting the local address
989 */
990static int apparmor_socket_getsockname(struct socket *sock)
991{
992 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
993}
994
995/**
996 * apparmor_socket_getpeername - check perms before getting remote address
997 */
998static int apparmor_socket_getpeername(struct socket *sock)
999{
1000 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
1001}
1002
1003/* revaliation, get/set attr, opt */
1004static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
1005 int level, int optname)
1006{
1007 AA_BUG(!sock);
1008 AA_BUG(!sock->sk);
1009 AA_BUG(in_interrupt());
1010
1011 return af_select(sock->sk->sk_family,
1012 opt_perm(op, request, sock, level, optname),
1013 aa_sk_perm(op, request, sock->sk));
1014}
1015
1016/**
1017 * apparmor_getsockopt - check perms before getting socket options
1018 */
1019static int apparmor_socket_getsockopt(struct socket *sock, int level,
1020 int optname)
1021{
1022 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
1023 level, optname);
1024}
1025
1026/**
1027 * apparmor_setsockopt - check perms before setting socket options
1028 */
1029static int apparmor_socket_setsockopt(struct socket *sock, int level,
1030 int optname)
1031{
1032 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1033 level, optname);
1034}
1035
1036/**
1037 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1038 */
1039static int apparmor_socket_shutdown(struct socket *sock, int how)
1040{
1041 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1042}
1043
1044#ifdef CONFIG_NETWORK_SECMARK
1045/**
1046 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1047 *
1048 * Note: can not sleep may be called with locks held
1049 *
1050 * dont want protocol specific in __skb_recv_datagram()
1051 * to deny an incoming connection socket_sock_rcv_skb()
1052 */
1053static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1054{
1055 struct aa_sk_ctx *ctx = SK_CTX(sk);
1056
1057 if (!skb->secmark)
1058 return 0;
1059
1060 return apparmor_secmark_check(ctx->label, OP_RECVMSG, AA_MAY_RECEIVE,
1061 skb->secmark, sk);
1062}
1063#endif
1064
1065
1066static struct aa_label *sk_peer_label(struct sock *sk)
1067{
1068 struct aa_sk_ctx *ctx = SK_CTX(sk);
1069
1070 if (ctx->peer)
1071 return ctx->peer;
1072
1073 return ERR_PTR(-ENOPROTOOPT);
1074}
1075
1076/**
1077 * apparmor_socket_getpeersec_stream - get security context of peer
1078 *
1079 * Note: for tcp only valid if using ipsec or cipso on lan
1080 */
1081static int apparmor_socket_getpeersec_stream(struct socket *sock,
1082 char __user *optval,
1083 int __user *optlen,
1084 unsigned int len)
1085{
1086 char *name;
1087 int slen, error = 0;
1088 struct aa_label *label;
1089 struct aa_label *peer;
1090
1091 label = begin_current_label_crit_section();
1092 peer = sk_peer_label(sock->sk);
1093 if (IS_ERR(peer)) {
1094 error = PTR_ERR(peer);
1095 goto done;
1096 }
1097 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1098 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1099 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1100 /* don't include terminating \0 in slen, it breaks some apps */
1101 if (slen < 0) {
1102 error = -ENOMEM;
1103 } else {
1104 if (slen > len) {
1105 error = -ERANGE;
1106 } else if (copy_to_user(optval, name, slen)) {
1107 error = -EFAULT;
1108 goto out;
1109 }
1110 if (put_user(slen, optlen))
1111 error = -EFAULT;
1112out:
1113 kfree(name);
1114
1115 }
1116
1117done:
1118 end_current_label_crit_section(label);
1119
1120 return error;
1121}
1122
1123/**
1124 * apparmor_socket_getpeersec_dgram - get security label of packet
1125 * @sock: the peer socket
1126 * @skb: packet data
1127 * @secid: pointer to where to put the secid of the packet
1128 *
1129 * Sets the netlabel socket state on sk from parent
1130 */
1131static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1132 struct sk_buff *skb, u32 *secid)
1133
1134{
1135 /* TODO: requires secid support */
1136 return -ENOPROTOOPT;
1137}
1138
1139/**
1140 * apparmor_sock_graft - Initialize newly created socket
1141 * @sk: child sock
1142 * @parent: parent socket
1143 *
1144 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1145 * just set sk security information off of current creating process label
1146 * Labeling of sk for accept case - probably should be sock based
1147 * instead of task, because of the case where an implicitly labeled
1148 * socket is shared by different tasks.
1149 */
1150static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1151{
1152 struct aa_sk_ctx *ctx = SK_CTX(sk);
1153
1154 if (!ctx->label)
1155 ctx->label = aa_get_current_label();
1156}
1157
1158#ifdef CONFIG_NETWORK_SECMARK
1159static int apparmor_inet_conn_request(const struct sock *sk, struct sk_buff *skb,
1160 struct request_sock *req)
1161{
1162 struct aa_sk_ctx *ctx = SK_CTX(sk);
1163
1164 if (!skb->secmark)
1165 return 0;
1166
1167 return apparmor_secmark_check(ctx->label, OP_CONNECT, AA_MAY_CONNECT,
1168 skb->secmark, sk);
1169}
1170#endif
1171
1172/*
1173 * The cred blob is a pointer to, not an instance of, an aa_task_ctx.
1174 */
1175struct lsm_blob_sizes apparmor_blob_sizes __lsm_ro_after_init = {
1176 .lbs_cred = sizeof(struct aa_task_ctx *),
1177 .lbs_file = sizeof(struct aa_file_ctx),
1178 .lbs_task = sizeof(struct aa_task_ctx),
1179};
1180
1181static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1182 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1183 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1184 LSM_HOOK_INIT(capget, apparmor_capget),
1185 LSM_HOOK_INIT(capable, apparmor_capable),
1186
1187 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1188 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1189 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1190
1191 LSM_HOOK_INIT(path_link, apparmor_path_link),
1192 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1193 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1194 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1195 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1196 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1197 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1198 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1199 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1200 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1201 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1202
1203 LSM_HOOK_INIT(file_open, apparmor_file_open),
1204 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1205 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1206 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1207 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1208 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1209 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1210 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1211
1212 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1213 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1214
1215 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1216 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1217 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1218
1219 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1220 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1221 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1222 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1223 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1224 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1225 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1226 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1227 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1228 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1229 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1230 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1231 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1232#ifdef CONFIG_NETWORK_SECMARK
1233 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1234#endif
1235 LSM_HOOK_INIT(socket_getpeersec_stream,
1236 apparmor_socket_getpeersec_stream),
1237 LSM_HOOK_INIT(socket_getpeersec_dgram,
1238 apparmor_socket_getpeersec_dgram),
1239 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1240#ifdef CONFIG_NETWORK_SECMARK
1241 LSM_HOOK_INIT(inet_conn_request, apparmor_inet_conn_request),
1242#endif
1243
1244 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1245 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1246 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1247 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1248
1249 LSM_HOOK_INIT(bprm_creds_for_exec, apparmor_bprm_creds_for_exec),
1250 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1251 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1252
1253 LSM_HOOK_INIT(task_free, apparmor_task_free),
1254 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1255 LSM_HOOK_INIT(task_getsecid_subj, apparmor_task_getsecid),
1256 LSM_HOOK_INIT(task_getsecid_obj, apparmor_task_getsecid),
1257 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1258 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1259
1260#ifdef CONFIG_AUDIT
1261 LSM_HOOK_INIT(audit_rule_init, aa_audit_rule_init),
1262 LSM_HOOK_INIT(audit_rule_known, aa_audit_rule_known),
1263 LSM_HOOK_INIT(audit_rule_match, aa_audit_rule_match),
1264 LSM_HOOK_INIT(audit_rule_free, aa_audit_rule_free),
1265#endif
1266
1267 LSM_HOOK_INIT(secid_to_secctx, apparmor_secid_to_secctx),
1268 LSM_HOOK_INIT(secctx_to_secid, apparmor_secctx_to_secid),
1269 LSM_HOOK_INIT(release_secctx, apparmor_release_secctx),
1270};
1271
1272/*
1273 * AppArmor sysfs module parameters
1274 */
1275
1276static int param_set_aabool(const char *val, const struct kernel_param *kp);
1277static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1278#define param_check_aabool param_check_bool
1279static const struct kernel_param_ops param_ops_aabool = {
1280 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1281 .set = param_set_aabool,
1282 .get = param_get_aabool
1283};
1284
1285static int param_set_aauint(const char *val, const struct kernel_param *kp);
1286static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1287#define param_check_aauint param_check_uint
1288static const struct kernel_param_ops param_ops_aauint = {
1289 .set = param_set_aauint,
1290 .get = param_get_aauint
1291};
1292
1293static int param_set_aacompressionlevel(const char *val,
1294 const struct kernel_param *kp);
1295static int param_get_aacompressionlevel(char *buffer,
1296 const struct kernel_param *kp);
1297#define param_check_aacompressionlevel param_check_int
1298static const struct kernel_param_ops param_ops_aacompressionlevel = {
1299 .set = param_set_aacompressionlevel,
1300 .get = param_get_aacompressionlevel
1301};
1302
1303static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1304static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1305#define param_check_aalockpolicy param_check_bool
1306static const struct kernel_param_ops param_ops_aalockpolicy = {
1307 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1308 .set = param_set_aalockpolicy,
1309 .get = param_get_aalockpolicy
1310};
1311
1312static int param_set_audit(const char *val, const struct kernel_param *kp);
1313static int param_get_audit(char *buffer, const struct kernel_param *kp);
1314
1315static int param_set_mode(const char *val, const struct kernel_param *kp);
1316static int param_get_mode(char *buffer, const struct kernel_param *kp);
1317
1318/* Flag values, also controllable via /sys/module/apparmor/parameters
1319 * We define special types as we want to do additional mediation.
1320 */
1321
1322/* AppArmor global enforcement switch - complain, enforce, kill */
1323enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1324module_param_call(mode, param_set_mode, param_get_mode,
1325 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1326
1327/* whether policy verification hashing is enabled */
1328bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1329#ifdef CONFIG_SECURITY_APPARMOR_HASH
1330module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1331#endif
1332
1333/* policy loaddata compression level */
1334int aa_g_rawdata_compression_level = Z_DEFAULT_COMPRESSION;
1335module_param_named(rawdata_compression_level, aa_g_rawdata_compression_level,
1336 aacompressionlevel, 0400);
1337
1338/* Debug mode */
1339bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1340module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1341
1342/* Audit mode */
1343enum audit_mode aa_g_audit;
1344module_param_call(audit, param_set_audit, param_get_audit,
1345 &aa_g_audit, S_IRUSR | S_IWUSR);
1346
1347/* Determines if audit header is included in audited messages. This
1348 * provides more context if the audit daemon is not running
1349 */
1350bool aa_g_audit_header = true;
1351module_param_named(audit_header, aa_g_audit_header, aabool,
1352 S_IRUSR | S_IWUSR);
1353
1354/* lock out loading/removal of policy
1355 * TODO: add in at boot loading of policy, which is the only way to
1356 * load policy, if lock_policy is set
1357 */
1358bool aa_g_lock_policy;
1359module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1360 S_IRUSR | S_IWUSR);
1361
1362/* Syscall logging mode */
1363bool aa_g_logsyscall;
1364module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1365
1366/* Maximum pathname length before accesses will start getting rejected */
1367unsigned int aa_g_path_max = 2 * PATH_MAX;
1368module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1369
1370/* Determines how paranoid loading of policy is and how much verification
1371 * on the loaded policy is done.
1372 * DEPRECATED: read only as strict checking of load is always done now
1373 * that none root users (user namespaces) can load policy.
1374 */
1375bool aa_g_paranoid_load = true;
1376module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1377
1378static int param_get_aaintbool(char *buffer, const struct kernel_param *kp);
1379static int param_set_aaintbool(const char *val, const struct kernel_param *kp);
1380#define param_check_aaintbool param_check_int
1381static const struct kernel_param_ops param_ops_aaintbool = {
1382 .set = param_set_aaintbool,
1383 .get = param_get_aaintbool
1384};
1385/* Boot time disable flag */
1386static int apparmor_enabled __lsm_ro_after_init = 1;
1387module_param_named(enabled, apparmor_enabled, aaintbool, 0444);
1388
1389static int __init apparmor_enabled_setup(char *str)
1390{
1391 unsigned long enabled;
1392 int error = kstrtoul(str, 0, &enabled);
1393 if (!error)
1394 apparmor_enabled = enabled ? 1 : 0;
1395 return 1;
1396}
1397
1398__setup("apparmor=", apparmor_enabled_setup);
1399
1400/* set global flag turning off the ability to load policy */
1401static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1402{
1403 if (!apparmor_enabled)
1404 return -EINVAL;
1405 if (apparmor_initialized && !policy_admin_capable(NULL))
1406 return -EPERM;
1407 return param_set_bool(val, kp);
1408}
1409
1410static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1411{
1412 if (!apparmor_enabled)
1413 return -EINVAL;
1414 if (apparmor_initialized && !policy_view_capable(NULL))
1415 return -EPERM;
1416 return param_get_bool(buffer, kp);
1417}
1418
1419static int param_set_aabool(const char *val, const struct kernel_param *kp)
1420{
1421 if (!apparmor_enabled)
1422 return -EINVAL;
1423 if (apparmor_initialized && !policy_admin_capable(NULL))
1424 return -EPERM;
1425 return param_set_bool(val, kp);
1426}
1427
1428static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1429{
1430 if (!apparmor_enabled)
1431 return -EINVAL;
1432 if (apparmor_initialized && !policy_view_capable(NULL))
1433 return -EPERM;
1434 return param_get_bool(buffer, kp);
1435}
1436
1437static int param_set_aauint(const char *val, const struct kernel_param *kp)
1438{
1439 int error;
1440
1441 if (!apparmor_enabled)
1442 return -EINVAL;
1443 /* file is ro but enforce 2nd line check */
1444 if (apparmor_initialized)
1445 return -EPERM;
1446
1447 error = param_set_uint(val, kp);
1448 aa_g_path_max = max_t(uint32_t, aa_g_path_max, sizeof(union aa_buffer));
1449 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1450
1451 return error;
1452}
1453
1454static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1455{
1456 if (!apparmor_enabled)
1457 return -EINVAL;
1458 if (apparmor_initialized && !policy_view_capable(NULL))
1459 return -EPERM;
1460 return param_get_uint(buffer, kp);
1461}
1462
1463/* Can only be set before AppArmor is initialized (i.e. on boot cmdline). */
1464static int param_set_aaintbool(const char *val, const struct kernel_param *kp)
1465{
1466 struct kernel_param kp_local;
1467 bool value;
1468 int error;
1469
1470 if (apparmor_initialized)
1471 return -EPERM;
1472
1473 /* Create local copy, with arg pointing to bool type. */
1474 value = !!*((int *)kp->arg);
1475 memcpy(&kp_local, kp, sizeof(kp_local));
1476 kp_local.arg = &value;
1477
1478 error = param_set_bool(val, &kp_local);
1479 if (!error)
1480 *((int *)kp->arg) = *((bool *)kp_local.arg);
1481 return error;
1482}
1483
1484/*
1485 * To avoid changing /sys/module/apparmor/parameters/enabled from Y/N to
1486 * 1/0, this converts the "int that is actually bool" back to bool for
1487 * display in the /sys filesystem, while keeping it "int" for the LSM
1488 * infrastructure.
1489 */
1490static int param_get_aaintbool(char *buffer, const struct kernel_param *kp)
1491{
1492 struct kernel_param kp_local;
1493 bool value;
1494
1495 /* Create local copy, with arg pointing to bool type. */
1496 value = !!*((int *)kp->arg);
1497 memcpy(&kp_local, kp, sizeof(kp_local));
1498 kp_local.arg = &value;
1499
1500 return param_get_bool(buffer, &kp_local);
1501}
1502
1503static int param_set_aacompressionlevel(const char *val,
1504 const struct kernel_param *kp)
1505{
1506 int error;
1507
1508 if (!apparmor_enabled)
1509 return -EINVAL;
1510 if (apparmor_initialized)
1511 return -EPERM;
1512
1513 error = param_set_int(val, kp);
1514
1515 aa_g_rawdata_compression_level = clamp(aa_g_rawdata_compression_level,
1516 Z_NO_COMPRESSION,
1517 Z_BEST_COMPRESSION);
1518 pr_info("AppArmor: policy rawdata compression level set to %u\n",
1519 aa_g_rawdata_compression_level);
1520
1521 return error;
1522}
1523
1524static int param_get_aacompressionlevel(char *buffer,
1525 const struct kernel_param *kp)
1526{
1527 if (!apparmor_enabled)
1528 return -EINVAL;
1529 if (apparmor_initialized && !policy_view_capable(NULL))
1530 return -EPERM;
1531 return param_get_int(buffer, kp);
1532}
1533
1534static int param_get_audit(char *buffer, const struct kernel_param *kp)
1535{
1536 if (!apparmor_enabled)
1537 return -EINVAL;
1538 if (apparmor_initialized && !policy_view_capable(NULL))
1539 return -EPERM;
1540 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1541}
1542
1543static int param_set_audit(const char *val, const struct kernel_param *kp)
1544{
1545 int i;
1546
1547 if (!apparmor_enabled)
1548 return -EINVAL;
1549 if (!val)
1550 return -EINVAL;
1551 if (apparmor_initialized && !policy_admin_capable(NULL))
1552 return -EPERM;
1553
1554 i = match_string(audit_mode_names, AUDIT_MAX_INDEX, val);
1555 if (i < 0)
1556 return -EINVAL;
1557
1558 aa_g_audit = i;
1559 return 0;
1560}
1561
1562static int param_get_mode(char *buffer, const struct kernel_param *kp)
1563{
1564 if (!apparmor_enabled)
1565 return -EINVAL;
1566 if (apparmor_initialized && !policy_view_capable(NULL))
1567 return -EPERM;
1568
1569 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1570}
1571
1572static int param_set_mode(const char *val, const struct kernel_param *kp)
1573{
1574 int i;
1575
1576 if (!apparmor_enabled)
1577 return -EINVAL;
1578 if (!val)
1579 return -EINVAL;
1580 if (apparmor_initialized && !policy_admin_capable(NULL))
1581 return -EPERM;
1582
1583 i = match_string(aa_profile_mode_names, APPARMOR_MODE_NAMES_MAX_INDEX,
1584 val);
1585 if (i < 0)
1586 return -EINVAL;
1587
1588 aa_g_profile_mode = i;
1589 return 0;
1590}
1591
1592char *aa_get_buffer(bool in_atomic)
1593{
1594 union aa_buffer *aa_buf;
1595 bool try_again = true;
1596 gfp_t flags = (GFP_KERNEL | __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1597
1598retry:
1599 spin_lock(&aa_buffers_lock);
1600 if (buffer_count > reserve_count ||
1601 (in_atomic && !list_empty(&aa_global_buffers))) {
1602 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1603 list);
1604 list_del(&aa_buf->list);
1605 buffer_count--;
1606 spin_unlock(&aa_buffers_lock);
1607 return &aa_buf->buffer[0];
1608 }
1609 if (in_atomic) {
1610 /*
1611 * out of reserve buffers and in atomic context so increase
1612 * how many buffers to keep in reserve
1613 */
1614 reserve_count++;
1615 flags = GFP_ATOMIC;
1616 }
1617 spin_unlock(&aa_buffers_lock);
1618
1619 if (!in_atomic)
1620 might_sleep();
1621 aa_buf = kmalloc(aa_g_path_max, flags);
1622 if (!aa_buf) {
1623 if (try_again) {
1624 try_again = false;
1625 goto retry;
1626 }
1627 pr_warn_once("AppArmor: Failed to allocate a memory buffer.\n");
1628 return NULL;
1629 }
1630 return &aa_buf->buffer[0];
1631}
1632
1633void aa_put_buffer(char *buf)
1634{
1635 union aa_buffer *aa_buf;
1636
1637 if (!buf)
1638 return;
1639 aa_buf = container_of(buf, union aa_buffer, buffer[0]);
1640
1641 spin_lock(&aa_buffers_lock);
1642 list_add(&aa_buf->list, &aa_global_buffers);
1643 buffer_count++;
1644 spin_unlock(&aa_buffers_lock);
1645}
1646
1647/*
1648 * AppArmor init functions
1649 */
1650
1651/**
1652 * set_init_ctx - set a task context and profile on the first task.
1653 *
1654 * TODO: allow setting an alternate profile than unconfined
1655 */
1656static int __init set_init_ctx(void)
1657{
1658 struct cred *cred = (__force struct cred *)current->real_cred;
1659
1660 set_cred_label(cred, aa_get_label(ns_unconfined(root_ns)));
1661
1662 return 0;
1663}
1664
1665static void destroy_buffers(void)
1666{
1667 union aa_buffer *aa_buf;
1668
1669 spin_lock(&aa_buffers_lock);
1670 while (!list_empty(&aa_global_buffers)) {
1671 aa_buf = list_first_entry(&aa_global_buffers, union aa_buffer,
1672 list);
1673 list_del(&aa_buf->list);
1674 spin_unlock(&aa_buffers_lock);
1675 kfree(aa_buf);
1676 spin_lock(&aa_buffers_lock);
1677 }
1678 spin_unlock(&aa_buffers_lock);
1679}
1680
1681static int __init alloc_buffers(void)
1682{
1683 union aa_buffer *aa_buf;
1684 int i, num;
1685
1686 /*
1687 * A function may require two buffers at once. Usually the buffers are
1688 * used for a short period of time and are shared. On UP kernel buffers
1689 * two should be enough, with more CPUs it is possible that more
1690 * buffers will be used simultaneously. The preallocated pool may grow.
1691 * This preallocation has also the side-effect that AppArmor will be
1692 * disabled early at boot if aa_g_path_max is extremly high.
1693 */
1694 if (num_online_cpus() > 1)
1695 num = 4 + RESERVE_COUNT;
1696 else
1697 num = 2 + RESERVE_COUNT;
1698
1699 for (i = 0; i < num; i++) {
1700
1701 aa_buf = kmalloc(aa_g_path_max, GFP_KERNEL |
1702 __GFP_RETRY_MAYFAIL | __GFP_NOWARN);
1703 if (!aa_buf) {
1704 destroy_buffers();
1705 return -ENOMEM;
1706 }
1707 aa_put_buffer(&aa_buf->buffer[0]);
1708 }
1709 return 0;
1710}
1711
1712#ifdef CONFIG_SYSCTL
1713static int apparmor_dointvec(struct ctl_table *table, int write,
1714 void *buffer, size_t *lenp, loff_t *ppos)
1715{
1716 if (!policy_admin_capable(NULL))
1717 return -EPERM;
1718 if (!apparmor_enabled)
1719 return -EINVAL;
1720
1721 return proc_dointvec(table, write, buffer, lenp, ppos);
1722}
1723
1724static struct ctl_path apparmor_sysctl_path[] = {
1725 { .procname = "kernel", },
1726 { }
1727};
1728
1729static struct ctl_table apparmor_sysctl_table[] = {
1730 {
1731 .procname = "unprivileged_userns_apparmor_policy",
1732 .data = &unprivileged_userns_apparmor_policy,
1733 .maxlen = sizeof(int),
1734 .mode = 0600,
1735 .proc_handler = apparmor_dointvec,
1736 },
1737 { }
1738};
1739
1740static int __init apparmor_init_sysctl(void)
1741{
1742 return register_sysctl_paths(apparmor_sysctl_path,
1743 apparmor_sysctl_table) ? 0 : -ENOMEM;
1744}
1745#else
1746static inline int apparmor_init_sysctl(void)
1747{
1748 return 0;
1749}
1750#endif /* CONFIG_SYSCTL */
1751
1752#if defined(CONFIG_NETFILTER) && defined(CONFIG_NETWORK_SECMARK)
1753static unsigned int apparmor_ip_postroute(void *priv,
1754 struct sk_buff *skb,
1755 const struct nf_hook_state *state)
1756{
1757 struct aa_sk_ctx *ctx;
1758 struct sock *sk;
1759
1760 if (!skb->secmark)
1761 return NF_ACCEPT;
1762
1763 sk = skb_to_full_sk(skb);
1764 if (sk == NULL)
1765 return NF_ACCEPT;
1766
1767 ctx = SK_CTX(sk);
1768 if (!apparmor_secmark_check(ctx->label, OP_SENDMSG, AA_MAY_SEND,
1769 skb->secmark, sk))
1770 return NF_ACCEPT;
1771
1772 return NF_DROP_ERR(-ECONNREFUSED);
1773
1774}
1775
1776static unsigned int apparmor_ipv4_postroute(void *priv,
1777 struct sk_buff *skb,
1778 const struct nf_hook_state *state)
1779{
1780 return apparmor_ip_postroute(priv, skb, state);
1781}
1782
1783#if IS_ENABLED(CONFIG_IPV6)
1784static unsigned int apparmor_ipv6_postroute(void *priv,
1785 struct sk_buff *skb,
1786 const struct nf_hook_state *state)
1787{
1788 return apparmor_ip_postroute(priv, skb, state);
1789}
1790#endif
1791
1792static const struct nf_hook_ops apparmor_nf_ops[] = {
1793 {
1794 .hook = apparmor_ipv4_postroute,
1795 .pf = NFPROTO_IPV4,
1796 .hooknum = NF_INET_POST_ROUTING,
1797 .priority = NF_IP_PRI_SELINUX_FIRST,
1798 },
1799#if IS_ENABLED(CONFIG_IPV6)
1800 {
1801 .hook = apparmor_ipv6_postroute,
1802 .pf = NFPROTO_IPV6,
1803 .hooknum = NF_INET_POST_ROUTING,
1804 .priority = NF_IP6_PRI_SELINUX_FIRST,
1805 },
1806#endif
1807};
1808
1809static int __net_init apparmor_nf_register(struct net *net)
1810{
1811 int ret;
1812
1813 ret = nf_register_net_hooks(net, apparmor_nf_ops,
1814 ARRAY_SIZE(apparmor_nf_ops));
1815 return ret;
1816}
1817
1818static void __net_exit apparmor_nf_unregister(struct net *net)
1819{
1820 nf_unregister_net_hooks(net, apparmor_nf_ops,
1821 ARRAY_SIZE(apparmor_nf_ops));
1822}
1823
1824static struct pernet_operations apparmor_net_ops = {
1825 .init = apparmor_nf_register,
1826 .exit = apparmor_nf_unregister,
1827};
1828
1829static int __init apparmor_nf_ip_init(void)
1830{
1831 int err;
1832
1833 if (!apparmor_enabled)
1834 return 0;
1835
1836 err = register_pernet_subsys(&apparmor_net_ops);
1837 if (err)
1838 panic("Apparmor: register_pernet_subsys: error %d\n", err);
1839
1840 return 0;
1841}
1842__initcall(apparmor_nf_ip_init);
1843#endif
1844
1845static int __init apparmor_init(void)
1846{
1847 int error;
1848
1849 aa_secids_init();
1850
1851 error = aa_setup_dfa_engine();
1852 if (error) {
1853 AA_ERROR("Unable to setup dfa engine\n");
1854 goto alloc_out;
1855 }
1856
1857 error = aa_alloc_root_ns();
1858 if (error) {
1859 AA_ERROR("Unable to allocate default profile namespace\n");
1860 goto alloc_out;
1861 }
1862
1863 error = apparmor_init_sysctl();
1864 if (error) {
1865 AA_ERROR("Unable to register sysctls\n");
1866 goto alloc_out;
1867
1868 }
1869
1870 error = alloc_buffers();
1871 if (error) {
1872 AA_ERROR("Unable to allocate work buffers\n");
1873 goto alloc_out;
1874 }
1875
1876 error = set_init_ctx();
1877 if (error) {
1878 AA_ERROR("Failed to set context on init task\n");
1879 aa_free_root_ns();
1880 goto buffers_out;
1881 }
1882 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1883 "apparmor");
1884
1885 /* Report that AppArmor successfully initialized */
1886 apparmor_initialized = 1;
1887 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1888 aa_info_message("AppArmor initialized: complain mode enabled");
1889 else if (aa_g_profile_mode == APPARMOR_KILL)
1890 aa_info_message("AppArmor initialized: kill mode enabled");
1891 else
1892 aa_info_message("AppArmor initialized");
1893
1894 return error;
1895
1896buffers_out:
1897 destroy_buffers();
1898alloc_out:
1899 aa_destroy_aafs();
1900 aa_teardown_dfa_engine();
1901
1902 apparmor_enabled = false;
1903 return error;
1904}
1905
1906DEFINE_LSM(apparmor) = {
1907 .name = "apparmor",
1908 .flags = LSM_FLAG_LEGACY_MAJOR | LSM_FLAG_EXCLUSIVE,
1909 .enabled = &apparmor_enabled,
1910 .blobs = &apparmor_blob_sizes,
1911 .init = apparmor_init,
1912};