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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->security);
52 cred->security = 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->security = 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, old->security);
81 new->security = 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 = old->security;
91 struct aa_task_cxt *new_cxt = new->security;
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(current, 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, uid_t uid, gid_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->f_path.dentry->d_inode))
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->f_path.dentry->d_inode;
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->f_path.dentry->d_inode))
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 struct dentry *dentry;
473 int mask = 0;
474
475 if (!file || !file->f_security)
476 return 0;
477
478 if (prot & PROT_READ)
479 mask |= MAY_READ;
480 /*
481 * Private mappings don't require write perms since they don't
482 * write back to the files
483 */
484 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
485 mask |= MAY_WRITE;
486 if (prot & PROT_EXEC)
487 mask |= AA_EXEC_MMAP;
488
489 dentry = file->f_path.dentry;
490 return common_file_perm(op, file, mask);
491}
492
493static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
494 unsigned long prot, unsigned long flags)
495{
496 return common_mmap(OP_FMMAP, file, prot, flags);
497}
498
499static int apparmor_file_mprotect(struct vm_area_struct *vma,
500 unsigned long reqprot, unsigned long prot)
501{
502 return common_mmap(OP_FMPROT, vma->vm_file, prot,
503 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
504}
505
506static int apparmor_getprocattr(struct task_struct *task, char *name,
507 char **value)
508{
509 int error = -ENOENT;
510 struct aa_profile *profile;
511 /* released below */
512 const struct cred *cred = get_task_cred(task);
513 struct aa_task_cxt *cxt = cred->security;
514 profile = aa_cred_profile(cred);
515
516 if (strcmp(name, "current") == 0)
517 error = aa_getprocattr(aa_newest_version(cxt->profile),
518 value);
519 else if (strcmp(name, "prev") == 0 && cxt->previous)
520 error = aa_getprocattr(aa_newest_version(cxt->previous),
521 value);
522 else if (strcmp(name, "exec") == 0 && cxt->onexec)
523 error = aa_getprocattr(aa_newest_version(cxt->onexec),
524 value);
525 else
526 error = -EINVAL;
527
528 put_cred(cred);
529
530 return error;
531}
532
533static int apparmor_setprocattr(struct task_struct *task, char *name,
534 void *value, size_t size)
535{
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 if (strcmp(command, "permipc") == 0) {
580 error = aa_setprocattr_permipc(args);
581 } else {
582 struct common_audit_data sa;
583 struct apparmor_audit_data aad = {0,};
584 sa.type = LSM_AUDIT_DATA_NONE;
585 sa.aad = &aad;
586 aad.op = OP_SETPROCATTR;
587 aad.info = name;
588 aad.error = -EINVAL;
589 return aa_audit(AUDIT_APPARMOR_DENIED,
590 __aa_current_profile(), GFP_KERNEL,
591 &sa, NULL);
592 }
593 } else if (strcmp(name, "exec") == 0) {
594 error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
595 !AA_DO_TEST);
596 } else {
597 /* only support the "current" and "exec" process attributes */
598 return -EINVAL;
599 }
600 if (!error)
601 error = size;
602 return error;
603}
604
605static int apparmor_task_setrlimit(struct task_struct *task,
606 unsigned int resource, struct rlimit *new_rlim)
607{
608 struct aa_profile *profile = __aa_current_profile();
609 int error = 0;
610
611 if (!unconfined(profile))
612 error = aa_task_setrlimit(profile, task, resource, new_rlim);
613
614 return error;
615}
616
617static struct security_operations apparmor_ops = {
618 .name = "apparmor",
619
620 .ptrace_access_check = apparmor_ptrace_access_check,
621 .ptrace_traceme = apparmor_ptrace_traceme,
622 .capget = apparmor_capget,
623 .capable = apparmor_capable,
624
625 .path_link = apparmor_path_link,
626 .path_unlink = apparmor_path_unlink,
627 .path_symlink = apparmor_path_symlink,
628 .path_mkdir = apparmor_path_mkdir,
629 .path_rmdir = apparmor_path_rmdir,
630 .path_mknod = apparmor_path_mknod,
631 .path_rename = apparmor_path_rename,
632 .path_chmod = apparmor_path_chmod,
633 .path_chown = apparmor_path_chown,
634 .path_truncate = apparmor_path_truncate,
635 .inode_getattr = apparmor_inode_getattr,
636
637 .file_open = apparmor_file_open,
638 .file_permission = apparmor_file_permission,
639 .file_alloc_security = apparmor_file_alloc_security,
640 .file_free_security = apparmor_file_free_security,
641 .mmap_file = apparmor_mmap_file,
642 .mmap_addr = cap_mmap_addr,
643 .file_mprotect = apparmor_file_mprotect,
644 .file_lock = apparmor_file_lock,
645
646 .getprocattr = apparmor_getprocattr,
647 .setprocattr = apparmor_setprocattr,
648
649 .cred_alloc_blank = apparmor_cred_alloc_blank,
650 .cred_free = apparmor_cred_free,
651 .cred_prepare = apparmor_cred_prepare,
652 .cred_transfer = apparmor_cred_transfer,
653
654 .bprm_set_creds = apparmor_bprm_set_creds,
655 .bprm_committing_creds = apparmor_bprm_committing_creds,
656 .bprm_committed_creds = apparmor_bprm_committed_creds,
657 .bprm_secureexec = apparmor_bprm_secureexec,
658
659 .task_setrlimit = apparmor_task_setrlimit,
660};
661
662/*
663 * AppArmor sysfs module parameters
664 */
665
666static int param_set_aabool(const char *val, const struct kernel_param *kp);
667static int param_get_aabool(char *buffer, const struct kernel_param *kp);
668#define param_check_aabool param_check_bool
669static struct kernel_param_ops param_ops_aabool = {
670 .set = param_set_aabool,
671 .get = param_get_aabool
672};
673
674static int param_set_aauint(const char *val, const struct kernel_param *kp);
675static int param_get_aauint(char *buffer, const struct kernel_param *kp);
676#define param_check_aauint param_check_uint
677static struct kernel_param_ops param_ops_aauint = {
678 .set = param_set_aauint,
679 .get = param_get_aauint
680};
681
682static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
683static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
684#define param_check_aalockpolicy param_check_bool
685static struct kernel_param_ops param_ops_aalockpolicy = {
686 .set = param_set_aalockpolicy,
687 .get = param_get_aalockpolicy
688};
689
690static int param_set_audit(const char *val, struct kernel_param *kp);
691static int param_get_audit(char *buffer, struct kernel_param *kp);
692
693static int param_set_mode(const char *val, struct kernel_param *kp);
694static int param_get_mode(char *buffer, struct kernel_param *kp);
695
696/* Flag values, also controllable via /sys/module/apparmor/parameters
697 * We define special types as we want to do additional mediation.
698 */
699
700/* AppArmor global enforcement switch - complain, enforce, kill */
701enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
702module_param_call(mode, param_set_mode, param_get_mode,
703 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
704
705/* Debug mode */
706bool aa_g_debug;
707module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
708
709/* Audit mode */
710enum audit_mode aa_g_audit;
711module_param_call(audit, param_set_audit, param_get_audit,
712 &aa_g_audit, S_IRUSR | S_IWUSR);
713
714/* Determines if audit header is included in audited messages. This
715 * provides more context if the audit daemon is not running
716 */
717bool aa_g_audit_header = 1;
718module_param_named(audit_header, aa_g_audit_header, aabool,
719 S_IRUSR | S_IWUSR);
720
721/* lock out loading/removal of policy
722 * TODO: add in at boot loading of policy, which is the only way to
723 * load policy, if lock_policy is set
724 */
725bool aa_g_lock_policy;
726module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
727 S_IRUSR | S_IWUSR);
728
729/* Syscall logging mode */
730bool aa_g_logsyscall;
731module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
732
733/* Maximum pathname length before accesses will start getting rejected */
734unsigned int aa_g_path_max = 2 * PATH_MAX;
735module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
736
737/* Determines how paranoid loading of policy is and how much verification
738 * on the loaded policy is done.
739 */
740bool aa_g_paranoid_load = 1;
741module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
742 S_IRUSR | S_IWUSR);
743
744/* Boot time disable flag */
745static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
746module_param_named(enabled, apparmor_enabled, aabool, S_IRUSR);
747
748static int __init apparmor_enabled_setup(char *str)
749{
750 unsigned long enabled;
751 int error = strict_strtoul(str, 0, &enabled);
752 if (!error)
753 apparmor_enabled = enabled ? 1 : 0;
754 return 1;
755}
756
757__setup("apparmor=", apparmor_enabled_setup);
758
759/* set global flag turning off the ability to load policy */
760static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
761{
762 if (!capable(CAP_MAC_ADMIN))
763 return -EPERM;
764 if (aa_g_lock_policy)
765 return -EACCES;
766 return param_set_bool(val, kp);
767}
768
769static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
770{
771 if (!capable(CAP_MAC_ADMIN))
772 return -EPERM;
773 return param_get_bool(buffer, kp);
774}
775
776static int param_set_aabool(const char *val, const struct kernel_param *kp)
777{
778 if (!capable(CAP_MAC_ADMIN))
779 return -EPERM;
780 return param_set_bool(val, kp);
781}
782
783static int param_get_aabool(char *buffer, const struct kernel_param *kp)
784{
785 if (!capable(CAP_MAC_ADMIN))
786 return -EPERM;
787 return param_get_bool(buffer, kp);
788}
789
790static int param_set_aauint(const char *val, const struct kernel_param *kp)
791{
792 if (!capable(CAP_MAC_ADMIN))
793 return -EPERM;
794 return param_set_uint(val, kp);
795}
796
797static int param_get_aauint(char *buffer, const struct kernel_param *kp)
798{
799 if (!capable(CAP_MAC_ADMIN))
800 return -EPERM;
801 return param_get_uint(buffer, kp);
802}
803
804static int param_get_audit(char *buffer, struct kernel_param *kp)
805{
806 if (!capable(CAP_MAC_ADMIN))
807 return -EPERM;
808
809 if (!apparmor_enabled)
810 return -EINVAL;
811
812 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
813}
814
815static int param_set_audit(const char *val, struct kernel_param *kp)
816{
817 int i;
818 if (!capable(CAP_MAC_ADMIN))
819 return -EPERM;
820
821 if (!apparmor_enabled)
822 return -EINVAL;
823
824 if (!val)
825 return -EINVAL;
826
827 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
828 if (strcmp(val, audit_mode_names[i]) == 0) {
829 aa_g_audit = i;
830 return 0;
831 }
832 }
833
834 return -EINVAL;
835}
836
837static int param_get_mode(char *buffer, struct kernel_param *kp)
838{
839 if (!capable(CAP_MAC_ADMIN))
840 return -EPERM;
841
842 if (!apparmor_enabled)
843 return -EINVAL;
844
845 return sprintf(buffer, "%s", profile_mode_names[aa_g_profile_mode]);
846}
847
848static int param_set_mode(const char *val, struct kernel_param *kp)
849{
850 int i;
851 if (!capable(CAP_MAC_ADMIN))
852 return -EPERM;
853
854 if (!apparmor_enabled)
855 return -EINVAL;
856
857 if (!val)
858 return -EINVAL;
859
860 for (i = 0; i < APPARMOR_NAMES_MAX_INDEX; i++) {
861 if (strcmp(val, profile_mode_names[i]) == 0) {
862 aa_g_profile_mode = i;
863 return 0;
864 }
865 }
866
867 return -EINVAL;
868}
869
870/*
871 * AppArmor init functions
872 */
873
874/**
875 * set_init_cxt - set a task context and profile on the first task.
876 *
877 * TODO: allow setting an alternate profile than unconfined
878 */
879static int __init set_init_cxt(void)
880{
881 struct cred *cred = (struct cred *)current->real_cred;
882 struct aa_task_cxt *cxt;
883
884 cxt = aa_alloc_task_context(GFP_KERNEL);
885 if (!cxt)
886 return -ENOMEM;
887
888 cxt->profile = aa_get_profile(root_ns->unconfined);
889 cred->security = cxt;
890
891 return 0;
892}
893
894static int __init apparmor_init(void)
895{
896 int error;
897
898 if (!apparmor_enabled || !security_module_enable(&apparmor_ops)) {
899 aa_info_message("AppArmor disabled by boot time parameter");
900 apparmor_enabled = 0;
901 return 0;
902 }
903
904 error = aa_alloc_root_ns();
905 if (error) {
906 AA_ERROR("Unable to allocate default profile namespace\n");
907 goto alloc_out;
908 }
909
910 error = set_init_cxt();
911 if (error) {
912 AA_ERROR("Failed to set context on init task\n");
913 goto register_security_out;
914 }
915
916 error = register_security(&apparmor_ops);
917 if (error) {
918 AA_ERROR("Unable to register AppArmor\n");
919 goto set_init_cxt_out;
920 }
921
922 /* Report that AppArmor successfully initialized */
923 apparmor_initialized = 1;
924 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
925 aa_info_message("AppArmor initialized: complain mode enabled");
926 else if (aa_g_profile_mode == APPARMOR_KILL)
927 aa_info_message("AppArmor initialized: kill mode enabled");
928 else
929 aa_info_message("AppArmor initialized");
930
931 return error;
932
933set_init_cxt_out:
934 aa_free_task_context(current->real_cred->security);
935
936register_security_out:
937 aa_free_root_ns();
938
939alloc_out:
940 aa_destroy_aafs();
941
942 apparmor_enabled = 0;
943 return error;
944}
945
946security_initcall(apparmor_init);
1/*
2 * AppArmor security module
3 *
4 * This file contains AppArmor LSM hooks.
5 *
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
8 *
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation, version 2 of the
12 * License.
13 */
14
15#include <linux/lsm_hooks.h>
16#include <linux/moduleparam.h>
17#include <linux/mm.h>
18#include <linux/mman.h>
19#include <linux/mount.h>
20#include <linux/namei.h>
21#include <linux/ptrace.h>
22#include <linux/ctype.h>
23#include <linux/sysctl.h>
24#include <linux/audit.h>
25#include <linux/user_namespace.h>
26#include <net/sock.h>
27
28#include "include/apparmor.h"
29#include "include/apparmorfs.h"
30#include "include/audit.h"
31#include "include/capability.h"
32#include "include/cred.h"
33#include "include/file.h"
34#include "include/ipc.h"
35#include "include/net.h"
36#include "include/path.h"
37#include "include/label.h"
38#include "include/policy.h"
39#include "include/policy_ns.h"
40#include "include/procattr.h"
41#include "include/mount.h"
42
43/* Flag indicating whether initialization completed */
44int apparmor_initialized;
45
46DEFINE_PER_CPU(struct aa_buffers, aa_buffers);
47
48
49/*
50 * LSM hook functions
51 */
52
53/*
54 * put the associated labels
55 */
56static void apparmor_cred_free(struct cred *cred)
57{
58 aa_put_label(cred_label(cred));
59 cred_label(cred) = NULL;
60}
61
62/*
63 * allocate the apparmor part of blank credentials
64 */
65static int apparmor_cred_alloc_blank(struct cred *cred, gfp_t gfp)
66{
67 cred_label(cred) = NULL;
68 return 0;
69}
70
71/*
72 * prepare new cred label for modification by prepare_cred block
73 */
74static int apparmor_cred_prepare(struct cred *new, const struct cred *old,
75 gfp_t gfp)
76{
77 cred_label(new) = aa_get_newest_label(cred_label(old));
78 return 0;
79}
80
81/*
82 * transfer the apparmor data to a blank set of creds
83 */
84static void apparmor_cred_transfer(struct cred *new, const struct cred *old)
85{
86 cred_label(new) = aa_get_newest_label(cred_label(old));
87}
88
89static void apparmor_task_free(struct task_struct *task)
90{
91
92 aa_free_task_ctx(task_ctx(task));
93 task_ctx(task) = NULL;
94}
95
96static int apparmor_task_alloc(struct task_struct *task,
97 unsigned long clone_flags)
98{
99 struct aa_task_ctx *new = aa_alloc_task_ctx(GFP_KERNEL);
100
101 if (!new)
102 return -ENOMEM;
103
104 aa_dup_task_ctx(new, task_ctx(current));
105 task_ctx(task) = new;
106
107 return 0;
108}
109
110static int apparmor_ptrace_access_check(struct task_struct *child,
111 unsigned int mode)
112{
113 struct aa_label *tracer, *tracee;
114 int error;
115
116 tracer = begin_current_label_crit_section();
117 tracee = aa_get_task_label(child);
118 error = aa_may_ptrace(tracer, tracee,
119 mode == PTRACE_MODE_READ ? AA_PTRACE_READ : AA_PTRACE_TRACE);
120 aa_put_label(tracee);
121 end_current_label_crit_section(tracer);
122
123 return error;
124}
125
126static int apparmor_ptrace_traceme(struct task_struct *parent)
127{
128 struct aa_label *tracer, *tracee;
129 int error;
130
131 tracee = begin_current_label_crit_section();
132 tracer = aa_get_task_label(parent);
133 error = aa_may_ptrace(tracer, tracee, AA_PTRACE_TRACE);
134 aa_put_label(tracer);
135 end_current_label_crit_section(tracee);
136
137 return error;
138}
139
140/* Derived from security/commoncap.c:cap_capget */
141static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
142 kernel_cap_t *inheritable, kernel_cap_t *permitted)
143{
144 struct aa_label *label;
145 const struct cred *cred;
146
147 rcu_read_lock();
148 cred = __task_cred(target);
149 label = aa_get_newest_cred_label(cred);
150
151 /*
152 * cap_capget is stacked ahead of this and will
153 * initialize effective and permitted.
154 */
155 if (!unconfined(label)) {
156 struct aa_profile *profile;
157 struct label_it i;
158
159 label_for_each_confined(i, label, profile) {
160 if (COMPLAIN_MODE(profile))
161 continue;
162 *effective = cap_intersect(*effective,
163 profile->caps.allow);
164 *permitted = cap_intersect(*permitted,
165 profile->caps.allow);
166 }
167 }
168 rcu_read_unlock();
169 aa_put_label(label);
170
171 return 0;
172}
173
174static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
175 int cap, int audit)
176{
177 struct aa_label *label;
178 int error = 0;
179
180 label = aa_get_newest_cred_label(cred);
181 if (!unconfined(label))
182 error = aa_capable(label, cap, audit);
183 aa_put_label(label);
184
185 return error;
186}
187
188/**
189 * common_perm - basic common permission check wrapper fn for paths
190 * @op: operation being checked
191 * @path: path to check permission of (NOT NULL)
192 * @mask: requested permissions mask
193 * @cond: conditional info for the permission request (NOT NULL)
194 *
195 * Returns: %0 else error code if error or permission denied
196 */
197static int common_perm(const char *op, const struct path *path, u32 mask,
198 struct path_cond *cond)
199{
200 struct aa_label *label;
201 int error = 0;
202
203 label = __begin_current_label_crit_section();
204 if (!unconfined(label))
205 error = aa_path_perm(op, label, path, 0, mask, cond);
206 __end_current_label_crit_section(label);
207
208 return error;
209}
210
211/**
212 * common_perm_cond - common permission wrapper around inode cond
213 * @op: operation being checked
214 * @path: location to check (NOT NULL)
215 * @mask: requested permissions mask
216 *
217 * Returns: %0 else error code if error or permission denied
218 */
219static int common_perm_cond(const char *op, const struct path *path, u32 mask)
220{
221 struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
222 d_backing_inode(path->dentry)->i_mode
223 };
224
225 if (!path_mediated_fs(path->dentry))
226 return 0;
227
228 return common_perm(op, path, mask, &cond);
229}
230
231/**
232 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
233 * @op: operation being checked
234 * @dir: directory of the dentry (NOT NULL)
235 * @dentry: dentry to check (NOT NULL)
236 * @mask: requested permissions mask
237 * @cond: conditional info for the permission request (NOT NULL)
238 *
239 * Returns: %0 else error code if error or permission denied
240 */
241static int common_perm_dir_dentry(const char *op, const struct path *dir,
242 struct dentry *dentry, u32 mask,
243 struct path_cond *cond)
244{
245 struct path path = { .mnt = dir->mnt, .dentry = dentry };
246
247 return common_perm(op, &path, mask, cond);
248}
249
250/**
251 * common_perm_rm - common permission wrapper for operations doing rm
252 * @op: operation being checked
253 * @dir: directory that the dentry is in (NOT NULL)
254 * @dentry: dentry being rm'd (NOT NULL)
255 * @mask: requested permission mask
256 *
257 * Returns: %0 else error code if error or permission denied
258 */
259static int common_perm_rm(const char *op, const struct path *dir,
260 struct dentry *dentry, u32 mask)
261{
262 struct inode *inode = d_backing_inode(dentry);
263 struct path_cond cond = { };
264
265 if (!inode || !path_mediated_fs(dentry))
266 return 0;
267
268 cond.uid = inode->i_uid;
269 cond.mode = inode->i_mode;
270
271 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
272}
273
274/**
275 * common_perm_create - common permission wrapper for operations doing create
276 * @op: operation being checked
277 * @dir: directory that dentry will be created in (NOT NULL)
278 * @dentry: dentry to create (NOT NULL)
279 * @mask: request permission mask
280 * @mode: created file mode
281 *
282 * Returns: %0 else error code if error or permission denied
283 */
284static int common_perm_create(const char *op, const struct path *dir,
285 struct dentry *dentry, u32 mask, umode_t mode)
286{
287 struct path_cond cond = { current_fsuid(), mode };
288
289 if (!path_mediated_fs(dir->dentry))
290 return 0;
291
292 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
293}
294
295static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
296{
297 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
298}
299
300static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
301 umode_t mode)
302{
303 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
304 S_IFDIR);
305}
306
307static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
308{
309 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
310}
311
312static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
313 umode_t mode, unsigned int dev)
314{
315 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
316}
317
318static int apparmor_path_truncate(const struct path *path)
319{
320 return common_perm_cond(OP_TRUNC, path, MAY_WRITE | AA_MAY_SETATTR);
321}
322
323static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
324 const char *old_name)
325{
326 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
327 S_IFLNK);
328}
329
330static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
331 struct dentry *new_dentry)
332{
333 struct aa_label *label;
334 int error = 0;
335
336 if (!path_mediated_fs(old_dentry))
337 return 0;
338
339 label = begin_current_label_crit_section();
340 if (!unconfined(label))
341 error = aa_path_link(label, old_dentry, new_dir, new_dentry);
342 end_current_label_crit_section(label);
343
344 return error;
345}
346
347static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
348 const struct path *new_dir, struct dentry *new_dentry)
349{
350 struct aa_label *label;
351 int error = 0;
352
353 if (!path_mediated_fs(old_dentry))
354 return 0;
355
356 label = begin_current_label_crit_section();
357 if (!unconfined(label)) {
358 struct path old_path = { .mnt = old_dir->mnt,
359 .dentry = old_dentry };
360 struct path new_path = { .mnt = new_dir->mnt,
361 .dentry = new_dentry };
362 struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
363 d_backing_inode(old_dentry)->i_mode
364 };
365
366 error = aa_path_perm(OP_RENAME_SRC, label, &old_path, 0,
367 MAY_READ | AA_MAY_GETATTR | MAY_WRITE |
368 AA_MAY_SETATTR | AA_MAY_DELETE,
369 &cond);
370 if (!error)
371 error = aa_path_perm(OP_RENAME_DEST, label, &new_path,
372 0, MAY_WRITE | AA_MAY_SETATTR |
373 AA_MAY_CREATE, &cond);
374
375 }
376 end_current_label_crit_section(label);
377
378 return error;
379}
380
381static int apparmor_path_chmod(const struct path *path, umode_t mode)
382{
383 return common_perm_cond(OP_CHMOD, path, AA_MAY_CHMOD);
384}
385
386static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
387{
388 return common_perm_cond(OP_CHOWN, path, AA_MAY_CHOWN);
389}
390
391static int apparmor_inode_getattr(const struct path *path)
392{
393 return common_perm_cond(OP_GETATTR, path, AA_MAY_GETATTR);
394}
395
396static int apparmor_file_open(struct file *file, const struct cred *cred)
397{
398 struct aa_file_ctx *fctx = file_ctx(file);
399 struct aa_label *label;
400 int error = 0;
401
402 if (!path_mediated_fs(file->f_path.dentry))
403 return 0;
404
405 /* If in exec, permission is handled by bprm hooks.
406 * Cache permissions granted by the previous exec check, with
407 * implicit read and executable mmap which are required to
408 * actually execute the image.
409 */
410 if (current->in_execve) {
411 fctx->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
412 return 0;
413 }
414
415 label = aa_get_newest_cred_label(cred);
416 if (!unconfined(label)) {
417 struct inode *inode = file_inode(file);
418 struct path_cond cond = { inode->i_uid, inode->i_mode };
419
420 error = aa_path_perm(OP_OPEN, label, &file->f_path, 0,
421 aa_map_file_to_perms(file), &cond);
422 /* todo cache full allowed permissions set and state */
423 fctx->allow = aa_map_file_to_perms(file);
424 }
425 aa_put_label(label);
426
427 return error;
428}
429
430static int apparmor_file_alloc_security(struct file *file)
431{
432 int error = 0;
433
434 /* freed by apparmor_file_free_security */
435 struct aa_label *label = begin_current_label_crit_section();
436 file->f_security = aa_alloc_file_ctx(label, GFP_KERNEL);
437 if (!file_ctx(file))
438 error = -ENOMEM;
439 end_current_label_crit_section(label);
440
441 return error;
442}
443
444static void apparmor_file_free_security(struct file *file)
445{
446 aa_free_file_ctx(file_ctx(file));
447}
448
449static int common_file_perm(const char *op, struct file *file, u32 mask)
450{
451 struct aa_label *label;
452 int error = 0;
453
454 /* don't reaudit files closed during inheritance */
455 if (file->f_path.dentry == aa_null.dentry)
456 return -EACCES;
457
458 label = __begin_current_label_crit_section();
459 error = aa_file_perm(op, label, file, mask);
460 __end_current_label_crit_section(label);
461
462 return error;
463}
464
465static int apparmor_file_receive(struct file *file)
466{
467 return common_file_perm(OP_FRECEIVE, file, aa_map_file_to_perms(file));
468}
469
470static int apparmor_file_permission(struct file *file, int mask)
471{
472 return common_file_perm(OP_FPERM, file, mask);
473}
474
475static int apparmor_file_lock(struct file *file, unsigned int cmd)
476{
477 u32 mask = AA_MAY_LOCK;
478
479 if (cmd == F_WRLCK)
480 mask |= MAY_WRITE;
481
482 return common_file_perm(OP_FLOCK, file, mask);
483}
484
485static int common_mmap(const char *op, struct file *file, unsigned long prot,
486 unsigned long flags)
487{
488 int mask = 0;
489
490 if (!file || !file_ctx(file))
491 return 0;
492
493 if (prot & PROT_READ)
494 mask |= MAY_READ;
495 /*
496 * Private mappings don't require write perms since they don't
497 * write back to the files
498 */
499 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
500 mask |= MAY_WRITE;
501 if (prot & PROT_EXEC)
502 mask |= AA_EXEC_MMAP;
503
504 return common_file_perm(op, file, mask);
505}
506
507static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
508 unsigned long prot, unsigned long flags)
509{
510 return common_mmap(OP_FMMAP, file, prot, flags);
511}
512
513static int apparmor_file_mprotect(struct vm_area_struct *vma,
514 unsigned long reqprot, unsigned long prot)
515{
516 return common_mmap(OP_FMPROT, vma->vm_file, prot,
517 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
518}
519
520static int apparmor_sb_mount(const char *dev_name, const struct path *path,
521 const char *type, unsigned long flags, void *data)
522{
523 struct aa_label *label;
524 int error = 0;
525
526 /* Discard magic */
527 if ((flags & MS_MGC_MSK) == MS_MGC_VAL)
528 flags &= ~MS_MGC_MSK;
529
530 flags &= ~AA_MS_IGNORE_MASK;
531
532 label = __begin_current_label_crit_section();
533 if (!unconfined(label)) {
534 if (flags & MS_REMOUNT)
535 error = aa_remount(label, path, flags, data);
536 else if (flags & MS_BIND)
537 error = aa_bind_mount(label, path, dev_name, flags);
538 else if (flags & (MS_SHARED | MS_PRIVATE | MS_SLAVE |
539 MS_UNBINDABLE))
540 error = aa_mount_change_type(label, path, flags);
541 else if (flags & MS_MOVE)
542 error = aa_move_mount(label, path, dev_name);
543 else
544 error = aa_new_mount(label, dev_name, path, type,
545 flags, data);
546 }
547 __end_current_label_crit_section(label);
548
549 return error;
550}
551
552static int apparmor_sb_umount(struct vfsmount *mnt, int flags)
553{
554 struct aa_label *label;
555 int error = 0;
556
557 label = __begin_current_label_crit_section();
558 if (!unconfined(label))
559 error = aa_umount(label, mnt, flags);
560 __end_current_label_crit_section(label);
561
562 return error;
563}
564
565static int apparmor_sb_pivotroot(const struct path *old_path,
566 const struct path *new_path)
567{
568 struct aa_label *label;
569 int error = 0;
570
571 label = aa_get_current_label();
572 if (!unconfined(label))
573 error = aa_pivotroot(label, old_path, new_path);
574 aa_put_label(label);
575
576 return error;
577}
578
579static int apparmor_getprocattr(struct task_struct *task, char *name,
580 char **value)
581{
582 int error = -ENOENT;
583 /* released below */
584 const struct cred *cred = get_task_cred(task);
585 struct aa_task_ctx *ctx = task_ctx(current);
586 struct aa_label *label = NULL;
587
588 if (strcmp(name, "current") == 0)
589 label = aa_get_newest_label(cred_label(cred));
590 else if (strcmp(name, "prev") == 0 && ctx->previous)
591 label = aa_get_newest_label(ctx->previous);
592 else if (strcmp(name, "exec") == 0 && ctx->onexec)
593 label = aa_get_newest_label(ctx->onexec);
594 else
595 error = -EINVAL;
596
597 if (label)
598 error = aa_getprocattr(label, value);
599
600 aa_put_label(label);
601 put_cred(cred);
602
603 return error;
604}
605
606static int apparmor_setprocattr(const char *name, void *value,
607 size_t size)
608{
609 char *command, *largs = NULL, *args = value;
610 size_t arg_size;
611 int error;
612 DEFINE_AUDIT_DATA(sa, LSM_AUDIT_DATA_NONE, OP_SETPROCATTR);
613
614 if (size == 0)
615 return -EINVAL;
616
617 /* AppArmor requires that the buffer must be null terminated atm */
618 if (args[size - 1] != '\0') {
619 /* null terminate */
620 largs = args = kmalloc(size + 1, GFP_KERNEL);
621 if (!args)
622 return -ENOMEM;
623 memcpy(args, value, size);
624 args[size] = '\0';
625 }
626
627 error = -EINVAL;
628 args = strim(args);
629 command = strsep(&args, " ");
630 if (!args)
631 goto out;
632 args = skip_spaces(args);
633 if (!*args)
634 goto out;
635
636 arg_size = size - (args - (largs ? largs : (char *) value));
637 if (strcmp(name, "current") == 0) {
638 if (strcmp(command, "changehat") == 0) {
639 error = aa_setprocattr_changehat(args, arg_size,
640 AA_CHANGE_NOFLAGS);
641 } else if (strcmp(command, "permhat") == 0) {
642 error = aa_setprocattr_changehat(args, arg_size,
643 AA_CHANGE_TEST);
644 } else if (strcmp(command, "changeprofile") == 0) {
645 error = aa_change_profile(args, AA_CHANGE_NOFLAGS);
646 } else if (strcmp(command, "permprofile") == 0) {
647 error = aa_change_profile(args, AA_CHANGE_TEST);
648 } else if (strcmp(command, "stack") == 0) {
649 error = aa_change_profile(args, AA_CHANGE_STACK);
650 } else
651 goto fail;
652 } else if (strcmp(name, "exec") == 0) {
653 if (strcmp(command, "exec") == 0)
654 error = aa_change_profile(args, AA_CHANGE_ONEXEC);
655 else if (strcmp(command, "stack") == 0)
656 error = aa_change_profile(args, (AA_CHANGE_ONEXEC |
657 AA_CHANGE_STACK));
658 else
659 goto fail;
660 } else
661 /* only support the "current" and "exec" process attributes */
662 goto fail;
663
664 if (!error)
665 error = size;
666out:
667 kfree(largs);
668 return error;
669
670fail:
671 aad(&sa)->label = begin_current_label_crit_section();
672 aad(&sa)->info = name;
673 aad(&sa)->error = error = -EINVAL;
674 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
675 end_current_label_crit_section(aad(&sa)->label);
676 goto out;
677}
678
679/**
680 * apparmor_bprm_committing_creds - do task cleanup on committing new creds
681 * @bprm: binprm for the exec (NOT NULL)
682 */
683static void apparmor_bprm_committing_creds(struct linux_binprm *bprm)
684{
685 struct aa_label *label = aa_current_raw_label();
686 struct aa_label *new_label = cred_label(bprm->cred);
687
688 /* bail out if unconfined or not changing profile */
689 if ((new_label->proxy == label->proxy) ||
690 (unconfined(new_label)))
691 return;
692
693 aa_inherit_files(bprm->cred, current->files);
694
695 current->pdeath_signal = 0;
696
697 /* reset soft limits and set hard limits for the new label */
698 __aa_transition_rlimits(label, new_label);
699}
700
701/**
702 * apparmor_bprm_committed_cred - do cleanup after new creds committed
703 * @bprm: binprm for the exec (NOT NULL)
704 */
705static void apparmor_bprm_committed_creds(struct linux_binprm *bprm)
706{
707 /* clear out temporary/transitional state from the context */
708 aa_clear_task_ctx_trans(task_ctx(current));
709
710 return;
711}
712
713static int apparmor_task_setrlimit(struct task_struct *task,
714 unsigned int resource, struct rlimit *new_rlim)
715{
716 struct aa_label *label = __begin_current_label_crit_section();
717 int error = 0;
718
719 if (!unconfined(label))
720 error = aa_task_setrlimit(label, task, resource, new_rlim);
721 __end_current_label_crit_section(label);
722
723 return error;
724}
725
726static int apparmor_task_kill(struct task_struct *target, struct siginfo *info,
727 int sig, const struct cred *cred)
728{
729 struct aa_label *cl, *tl;
730 int error;
731
732 if (cred) {
733 /*
734 * Dealing with USB IO specific behavior
735 */
736 cl = aa_get_newest_cred_label(cred);
737 tl = aa_get_task_label(target);
738 error = aa_may_signal(cl, tl, sig);
739 aa_put_label(cl);
740 aa_put_label(tl);
741 return error;
742 }
743
744 cl = __begin_current_label_crit_section();
745 tl = aa_get_task_label(target);
746 error = aa_may_signal(cl, tl, sig);
747 aa_put_label(tl);
748 __end_current_label_crit_section(cl);
749
750 return error;
751}
752
753/**
754 * apparmor_sk_alloc_security - allocate and attach the sk_security field
755 */
756static int apparmor_sk_alloc_security(struct sock *sk, int family, gfp_t flags)
757{
758 struct aa_sk_ctx *ctx;
759
760 ctx = kzalloc(sizeof(*ctx), flags);
761 if (!ctx)
762 return -ENOMEM;
763
764 SK_CTX(sk) = ctx;
765
766 return 0;
767}
768
769/**
770 * apparmor_sk_free_security - free the sk_security field
771 */
772static void apparmor_sk_free_security(struct sock *sk)
773{
774 struct aa_sk_ctx *ctx = SK_CTX(sk);
775
776 SK_CTX(sk) = NULL;
777 aa_put_label(ctx->label);
778 aa_put_label(ctx->peer);
779 kfree(ctx);
780}
781
782/**
783 * apparmor_clone_security - clone the sk_security field
784 */
785static void apparmor_sk_clone_security(const struct sock *sk,
786 struct sock *newsk)
787{
788 struct aa_sk_ctx *ctx = SK_CTX(sk);
789 struct aa_sk_ctx *new = SK_CTX(newsk);
790
791 new->label = aa_get_label(ctx->label);
792 new->peer = aa_get_label(ctx->peer);
793}
794
795/**
796 * apparmor_socket_create - check perms before creating a new socket
797 */
798static int apparmor_socket_create(int family, int type, int protocol, int kern)
799{
800 struct aa_label *label;
801 int error = 0;
802
803 AA_BUG(in_interrupt());
804
805 label = begin_current_label_crit_section();
806 if (!(kern || unconfined(label)))
807 error = af_select(family,
808 create_perm(label, family, type, protocol),
809 aa_af_perm(label, OP_CREATE, AA_MAY_CREATE,
810 family, type, protocol));
811 end_current_label_crit_section(label);
812
813 return error;
814}
815
816/**
817 * apparmor_socket_post_create - setup the per-socket security struct
818 *
819 * Note:
820 * - kernel sockets currently labeled unconfined but we may want to
821 * move to a special kernel label
822 * - socket may not have sk here if created with sock_create_lite or
823 * sock_alloc. These should be accept cases which will be handled in
824 * sock_graft.
825 */
826static int apparmor_socket_post_create(struct socket *sock, int family,
827 int type, int protocol, int kern)
828{
829 struct aa_label *label;
830
831 if (kern) {
832 struct aa_ns *ns = aa_get_current_ns();
833
834 label = aa_get_label(ns_unconfined(ns));
835 aa_put_ns(ns);
836 } else
837 label = aa_get_current_label();
838
839 if (sock->sk) {
840 struct aa_sk_ctx *ctx = SK_CTX(sock->sk);
841
842 aa_put_label(ctx->label);
843 ctx->label = aa_get_label(label);
844 }
845 aa_put_label(label);
846
847 return 0;
848}
849
850/**
851 * apparmor_socket_bind - check perms before bind addr to socket
852 */
853static int apparmor_socket_bind(struct socket *sock,
854 struct sockaddr *address, int addrlen)
855{
856 AA_BUG(!sock);
857 AA_BUG(!sock->sk);
858 AA_BUG(!address);
859 AA_BUG(in_interrupt());
860
861 return af_select(sock->sk->sk_family,
862 bind_perm(sock, address, addrlen),
863 aa_sk_perm(OP_BIND, AA_MAY_BIND, sock->sk));
864}
865
866/**
867 * apparmor_socket_connect - check perms before connecting @sock to @address
868 */
869static int apparmor_socket_connect(struct socket *sock,
870 struct sockaddr *address, int addrlen)
871{
872 AA_BUG(!sock);
873 AA_BUG(!sock->sk);
874 AA_BUG(!address);
875 AA_BUG(in_interrupt());
876
877 return af_select(sock->sk->sk_family,
878 connect_perm(sock, address, addrlen),
879 aa_sk_perm(OP_CONNECT, AA_MAY_CONNECT, sock->sk));
880}
881
882/**
883 * apparmor_socket_list - check perms before allowing listen
884 */
885static int apparmor_socket_listen(struct socket *sock, int backlog)
886{
887 AA_BUG(!sock);
888 AA_BUG(!sock->sk);
889 AA_BUG(in_interrupt());
890
891 return af_select(sock->sk->sk_family,
892 listen_perm(sock, backlog),
893 aa_sk_perm(OP_LISTEN, AA_MAY_LISTEN, sock->sk));
894}
895
896/**
897 * apparmor_socket_accept - check perms before accepting a new connection.
898 *
899 * Note: while @newsock is created and has some information, the accept
900 * has not been done.
901 */
902static int apparmor_socket_accept(struct socket *sock, struct socket *newsock)
903{
904 AA_BUG(!sock);
905 AA_BUG(!sock->sk);
906 AA_BUG(!newsock);
907 AA_BUG(in_interrupt());
908
909 return af_select(sock->sk->sk_family,
910 accept_perm(sock, newsock),
911 aa_sk_perm(OP_ACCEPT, AA_MAY_ACCEPT, sock->sk));
912}
913
914static int aa_sock_msg_perm(const char *op, u32 request, struct socket *sock,
915 struct msghdr *msg, int size)
916{
917 AA_BUG(!sock);
918 AA_BUG(!sock->sk);
919 AA_BUG(!msg);
920 AA_BUG(in_interrupt());
921
922 return af_select(sock->sk->sk_family,
923 msg_perm(op, request, sock, msg, size),
924 aa_sk_perm(op, request, sock->sk));
925}
926
927/**
928 * apparmor_socket_sendmsg - check perms before sending msg to another socket
929 */
930static int apparmor_socket_sendmsg(struct socket *sock,
931 struct msghdr *msg, int size)
932{
933 return aa_sock_msg_perm(OP_SENDMSG, AA_MAY_SEND, sock, msg, size);
934}
935
936/**
937 * apparmor_socket_recvmsg - check perms before receiving a message
938 */
939static int apparmor_socket_recvmsg(struct socket *sock,
940 struct msghdr *msg, int size, int flags)
941{
942 return aa_sock_msg_perm(OP_RECVMSG, AA_MAY_RECEIVE, sock, msg, size);
943}
944
945/* revaliation, get/set attr, shutdown */
946static int aa_sock_perm(const char *op, u32 request, struct socket *sock)
947{
948 AA_BUG(!sock);
949 AA_BUG(!sock->sk);
950 AA_BUG(in_interrupt());
951
952 return af_select(sock->sk->sk_family,
953 sock_perm(op, request, sock),
954 aa_sk_perm(op, request, sock->sk));
955}
956
957/**
958 * apparmor_socket_getsockname - check perms before getting the local address
959 */
960static int apparmor_socket_getsockname(struct socket *sock)
961{
962 return aa_sock_perm(OP_GETSOCKNAME, AA_MAY_GETATTR, sock);
963}
964
965/**
966 * apparmor_socket_getpeername - check perms before getting remote address
967 */
968static int apparmor_socket_getpeername(struct socket *sock)
969{
970 return aa_sock_perm(OP_GETPEERNAME, AA_MAY_GETATTR, sock);
971}
972
973/* revaliation, get/set attr, opt */
974static int aa_sock_opt_perm(const char *op, u32 request, struct socket *sock,
975 int level, int optname)
976{
977 AA_BUG(!sock);
978 AA_BUG(!sock->sk);
979 AA_BUG(in_interrupt());
980
981 return af_select(sock->sk->sk_family,
982 opt_perm(op, request, sock, level, optname),
983 aa_sk_perm(op, request, sock->sk));
984}
985
986/**
987 * apparmor_getsockopt - check perms before getting socket options
988 */
989static int apparmor_socket_getsockopt(struct socket *sock, int level,
990 int optname)
991{
992 return aa_sock_opt_perm(OP_GETSOCKOPT, AA_MAY_GETOPT, sock,
993 level, optname);
994}
995
996/**
997 * apparmor_setsockopt - check perms before setting socket options
998 */
999static int apparmor_socket_setsockopt(struct socket *sock, int level,
1000 int optname)
1001{
1002 return aa_sock_opt_perm(OP_SETSOCKOPT, AA_MAY_SETOPT, sock,
1003 level, optname);
1004}
1005
1006/**
1007 * apparmor_socket_shutdown - check perms before shutting down @sock conn
1008 */
1009static int apparmor_socket_shutdown(struct socket *sock, int how)
1010{
1011 return aa_sock_perm(OP_SHUTDOWN, AA_MAY_SHUTDOWN, sock);
1012}
1013
1014/**
1015 * apparmor_socket_sock_recv_skb - check perms before associating skb to sk
1016 *
1017 * Note: can not sleep may be called with locks held
1018 *
1019 * dont want protocol specific in __skb_recv_datagram()
1020 * to deny an incoming connection socket_sock_rcv_skb()
1021 */
1022static int apparmor_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
1023{
1024 return 0;
1025}
1026
1027
1028static struct aa_label *sk_peer_label(struct sock *sk)
1029{
1030 struct aa_sk_ctx *ctx = SK_CTX(sk);
1031
1032 if (ctx->peer)
1033 return ctx->peer;
1034
1035 return ERR_PTR(-ENOPROTOOPT);
1036}
1037
1038/**
1039 * apparmor_socket_getpeersec_stream - get security context of peer
1040 *
1041 * Note: for tcp only valid if using ipsec or cipso on lan
1042 */
1043static int apparmor_socket_getpeersec_stream(struct socket *sock,
1044 char __user *optval,
1045 int __user *optlen,
1046 unsigned int len)
1047{
1048 char *name;
1049 int slen, error = 0;
1050 struct aa_label *label;
1051 struct aa_label *peer;
1052
1053 label = begin_current_label_crit_section();
1054 peer = sk_peer_label(sock->sk);
1055 if (IS_ERR(peer)) {
1056 error = PTR_ERR(peer);
1057 goto done;
1058 }
1059 slen = aa_label_asxprint(&name, labels_ns(label), peer,
1060 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS |
1061 FLAG_HIDDEN_UNCONFINED, GFP_KERNEL);
1062 /* don't include terminating \0 in slen, it breaks some apps */
1063 if (slen < 0) {
1064 error = -ENOMEM;
1065 } else {
1066 if (slen > len) {
1067 error = -ERANGE;
1068 } else if (copy_to_user(optval, name, slen)) {
1069 error = -EFAULT;
1070 goto out;
1071 }
1072 if (put_user(slen, optlen))
1073 error = -EFAULT;
1074out:
1075 kfree(name);
1076
1077 }
1078
1079done:
1080 end_current_label_crit_section(label);
1081
1082 return error;
1083}
1084
1085/**
1086 * apparmor_socket_getpeersec_dgram - get security label of packet
1087 * @sock: the peer socket
1088 * @skb: packet data
1089 * @secid: pointer to where to put the secid of the packet
1090 *
1091 * Sets the netlabel socket state on sk from parent
1092 */
1093static int apparmor_socket_getpeersec_dgram(struct socket *sock,
1094 struct sk_buff *skb, u32 *secid)
1095
1096{
1097 /* TODO: requires secid support */
1098 return -ENOPROTOOPT;
1099}
1100
1101/**
1102 * apparmor_sock_graft - Initialize newly created socket
1103 * @sk: child sock
1104 * @parent: parent socket
1105 *
1106 * Note: could set off of SOCK_CTX(parent) but need to track inode and we can
1107 * just set sk security information off of current creating process label
1108 * Labeling of sk for accept case - probably should be sock based
1109 * instead of task, because of the case where an implicitly labeled
1110 * socket is shared by different tasks.
1111 */
1112static void apparmor_sock_graft(struct sock *sk, struct socket *parent)
1113{
1114 struct aa_sk_ctx *ctx = SK_CTX(sk);
1115
1116 if (!ctx->label)
1117 ctx->label = aa_get_current_label();
1118}
1119
1120static struct security_hook_list apparmor_hooks[] __lsm_ro_after_init = {
1121 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
1122 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
1123 LSM_HOOK_INIT(capget, apparmor_capget),
1124 LSM_HOOK_INIT(capable, apparmor_capable),
1125
1126 LSM_HOOK_INIT(sb_mount, apparmor_sb_mount),
1127 LSM_HOOK_INIT(sb_umount, apparmor_sb_umount),
1128 LSM_HOOK_INIT(sb_pivotroot, apparmor_sb_pivotroot),
1129
1130 LSM_HOOK_INIT(path_link, apparmor_path_link),
1131 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
1132 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
1133 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
1134 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
1135 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
1136 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
1137 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
1138 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
1139 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
1140 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
1141
1142 LSM_HOOK_INIT(file_open, apparmor_file_open),
1143 LSM_HOOK_INIT(file_receive, apparmor_file_receive),
1144 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
1145 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
1146 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
1147 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
1148 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
1149 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
1150
1151 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
1152 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
1153
1154 LSM_HOOK_INIT(sk_alloc_security, apparmor_sk_alloc_security),
1155 LSM_HOOK_INIT(sk_free_security, apparmor_sk_free_security),
1156 LSM_HOOK_INIT(sk_clone_security, apparmor_sk_clone_security),
1157
1158 LSM_HOOK_INIT(socket_create, apparmor_socket_create),
1159 LSM_HOOK_INIT(socket_post_create, apparmor_socket_post_create),
1160 LSM_HOOK_INIT(socket_bind, apparmor_socket_bind),
1161 LSM_HOOK_INIT(socket_connect, apparmor_socket_connect),
1162 LSM_HOOK_INIT(socket_listen, apparmor_socket_listen),
1163 LSM_HOOK_INIT(socket_accept, apparmor_socket_accept),
1164 LSM_HOOK_INIT(socket_sendmsg, apparmor_socket_sendmsg),
1165 LSM_HOOK_INIT(socket_recvmsg, apparmor_socket_recvmsg),
1166 LSM_HOOK_INIT(socket_getsockname, apparmor_socket_getsockname),
1167 LSM_HOOK_INIT(socket_getpeername, apparmor_socket_getpeername),
1168 LSM_HOOK_INIT(socket_getsockopt, apparmor_socket_getsockopt),
1169 LSM_HOOK_INIT(socket_setsockopt, apparmor_socket_setsockopt),
1170 LSM_HOOK_INIT(socket_shutdown, apparmor_socket_shutdown),
1171 LSM_HOOK_INIT(socket_sock_rcv_skb, apparmor_socket_sock_rcv_skb),
1172 LSM_HOOK_INIT(socket_getpeersec_stream,
1173 apparmor_socket_getpeersec_stream),
1174 LSM_HOOK_INIT(socket_getpeersec_dgram,
1175 apparmor_socket_getpeersec_dgram),
1176 LSM_HOOK_INIT(sock_graft, apparmor_sock_graft),
1177
1178 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
1179 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
1180 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
1181 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
1182
1183 LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
1184 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
1185 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
1186
1187 LSM_HOOK_INIT(task_free, apparmor_task_free),
1188 LSM_HOOK_INIT(task_alloc, apparmor_task_alloc),
1189 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
1190 LSM_HOOK_INIT(task_kill, apparmor_task_kill),
1191};
1192
1193/*
1194 * AppArmor sysfs module parameters
1195 */
1196
1197static int param_set_aabool(const char *val, const struct kernel_param *kp);
1198static int param_get_aabool(char *buffer, const struct kernel_param *kp);
1199#define param_check_aabool param_check_bool
1200static const struct kernel_param_ops param_ops_aabool = {
1201 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1202 .set = param_set_aabool,
1203 .get = param_get_aabool
1204};
1205
1206static int param_set_aauint(const char *val, const struct kernel_param *kp);
1207static int param_get_aauint(char *buffer, const struct kernel_param *kp);
1208#define param_check_aauint param_check_uint
1209static const struct kernel_param_ops param_ops_aauint = {
1210 .set = param_set_aauint,
1211 .get = param_get_aauint
1212};
1213
1214static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
1215static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
1216#define param_check_aalockpolicy param_check_bool
1217static const struct kernel_param_ops param_ops_aalockpolicy = {
1218 .flags = KERNEL_PARAM_OPS_FL_NOARG,
1219 .set = param_set_aalockpolicy,
1220 .get = param_get_aalockpolicy
1221};
1222
1223static int param_set_audit(const char *val, const struct kernel_param *kp);
1224static int param_get_audit(char *buffer, const struct kernel_param *kp);
1225
1226static int param_set_mode(const char *val, const struct kernel_param *kp);
1227static int param_get_mode(char *buffer, const struct kernel_param *kp);
1228
1229/* Flag values, also controllable via /sys/module/apparmor/parameters
1230 * We define special types as we want to do additional mediation.
1231 */
1232
1233/* AppArmor global enforcement switch - complain, enforce, kill */
1234enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
1235module_param_call(mode, param_set_mode, param_get_mode,
1236 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
1237
1238/* whether policy verification hashing is enabled */
1239bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
1240#ifdef CONFIG_SECURITY_APPARMOR_HASH
1241module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
1242#endif
1243
1244/* Debug mode */
1245bool aa_g_debug = IS_ENABLED(CONFIG_SECURITY_APPARMOR_DEBUG_MESSAGES);
1246module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
1247
1248/* Audit mode */
1249enum audit_mode aa_g_audit;
1250module_param_call(audit, param_set_audit, param_get_audit,
1251 &aa_g_audit, S_IRUSR | S_IWUSR);
1252
1253/* Determines if audit header is included in audited messages. This
1254 * provides more context if the audit daemon is not running
1255 */
1256bool aa_g_audit_header = true;
1257module_param_named(audit_header, aa_g_audit_header, aabool,
1258 S_IRUSR | S_IWUSR);
1259
1260/* lock out loading/removal of policy
1261 * TODO: add in at boot loading of policy, which is the only way to
1262 * load policy, if lock_policy is set
1263 */
1264bool aa_g_lock_policy;
1265module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
1266 S_IRUSR | S_IWUSR);
1267
1268/* Syscall logging mode */
1269bool aa_g_logsyscall;
1270module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
1271
1272/* Maximum pathname length before accesses will start getting rejected */
1273unsigned int aa_g_path_max = 2 * PATH_MAX;
1274module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR);
1275
1276/* Determines how paranoid loading of policy is and how much verification
1277 * on the loaded policy is done.
1278 * DEPRECATED: read only as strict checking of load is always done now
1279 * that none root users (user namespaces) can load policy.
1280 */
1281bool aa_g_paranoid_load = true;
1282module_param_named(paranoid_load, aa_g_paranoid_load, aabool, S_IRUGO);
1283
1284/* Boot time disable flag */
1285static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
1286module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
1287
1288static int __init apparmor_enabled_setup(char *str)
1289{
1290 unsigned long enabled;
1291 int error = kstrtoul(str, 0, &enabled);
1292 if (!error)
1293 apparmor_enabled = enabled ? 1 : 0;
1294 return 1;
1295}
1296
1297__setup("apparmor=", apparmor_enabled_setup);
1298
1299/* set global flag turning off the ability to load policy */
1300static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
1301{
1302 if (!apparmor_enabled)
1303 return -EINVAL;
1304 if (apparmor_initialized && !policy_admin_capable(NULL))
1305 return -EPERM;
1306 return param_set_bool(val, kp);
1307}
1308
1309static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
1310{
1311 if (!apparmor_enabled)
1312 return -EINVAL;
1313 if (apparmor_initialized && !policy_view_capable(NULL))
1314 return -EPERM;
1315 return param_get_bool(buffer, kp);
1316}
1317
1318static int param_set_aabool(const char *val, const struct kernel_param *kp)
1319{
1320 if (!apparmor_enabled)
1321 return -EINVAL;
1322 if (apparmor_initialized && !policy_admin_capable(NULL))
1323 return -EPERM;
1324 return param_set_bool(val, kp);
1325}
1326
1327static int param_get_aabool(char *buffer, const struct kernel_param *kp)
1328{
1329 if (!apparmor_enabled)
1330 return -EINVAL;
1331 if (apparmor_initialized && !policy_view_capable(NULL))
1332 return -EPERM;
1333 return param_get_bool(buffer, kp);
1334}
1335
1336static int param_set_aauint(const char *val, const struct kernel_param *kp)
1337{
1338 int error;
1339
1340 if (!apparmor_enabled)
1341 return -EINVAL;
1342 /* file is ro but enforce 2nd line check */
1343 if (apparmor_initialized)
1344 return -EPERM;
1345
1346 error = param_set_uint(val, kp);
1347 pr_info("AppArmor: buffer size set to %d bytes\n", aa_g_path_max);
1348
1349 return error;
1350}
1351
1352static int param_get_aauint(char *buffer, const struct kernel_param *kp)
1353{
1354 if (!apparmor_enabled)
1355 return -EINVAL;
1356 if (apparmor_initialized && !policy_view_capable(NULL))
1357 return -EPERM;
1358 return param_get_uint(buffer, kp);
1359}
1360
1361static int param_get_audit(char *buffer, const struct kernel_param *kp)
1362{
1363 if (!apparmor_enabled)
1364 return -EINVAL;
1365 if (apparmor_initialized && !policy_view_capable(NULL))
1366 return -EPERM;
1367 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
1368}
1369
1370static int param_set_audit(const char *val, const struct kernel_param *kp)
1371{
1372 int i;
1373
1374 if (!apparmor_enabled)
1375 return -EINVAL;
1376 if (!val)
1377 return -EINVAL;
1378 if (apparmor_initialized && !policy_admin_capable(NULL))
1379 return -EPERM;
1380
1381 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
1382 if (strcmp(val, audit_mode_names[i]) == 0) {
1383 aa_g_audit = i;
1384 return 0;
1385 }
1386 }
1387
1388 return -EINVAL;
1389}
1390
1391static int param_get_mode(char *buffer, const struct kernel_param *kp)
1392{
1393 if (!apparmor_enabled)
1394 return -EINVAL;
1395 if (apparmor_initialized && !policy_view_capable(NULL))
1396 return -EPERM;
1397
1398 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
1399}
1400
1401static int param_set_mode(const char *val, const struct kernel_param *kp)
1402{
1403 int i;
1404
1405 if (!apparmor_enabled)
1406 return -EINVAL;
1407 if (!val)
1408 return -EINVAL;
1409 if (apparmor_initialized && !policy_admin_capable(NULL))
1410 return -EPERM;
1411
1412 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
1413 if (strcmp(val, aa_profile_mode_names[i]) == 0) {
1414 aa_g_profile_mode = i;
1415 return 0;
1416 }
1417 }
1418
1419 return -EINVAL;
1420}
1421
1422/*
1423 * AppArmor init functions
1424 */
1425
1426/**
1427 * set_init_ctx - set a task context and profile on the first task.
1428 *
1429 * TODO: allow setting an alternate profile than unconfined
1430 */
1431static int __init set_init_ctx(void)
1432{
1433 struct cred *cred = (struct cred *)current->real_cred;
1434 struct aa_task_ctx *ctx;
1435
1436 ctx = aa_alloc_task_ctx(GFP_KERNEL);
1437 if (!ctx)
1438 return -ENOMEM;
1439
1440 cred_label(cred) = aa_get_label(ns_unconfined(root_ns));
1441 task_ctx(current) = ctx;
1442
1443 return 0;
1444}
1445
1446static void destroy_buffers(void)
1447{
1448 u32 i, j;
1449
1450 for_each_possible_cpu(i) {
1451 for_each_cpu_buffer(j) {
1452 kfree(per_cpu(aa_buffers, i).buf[j]);
1453 per_cpu(aa_buffers, i).buf[j] = NULL;
1454 }
1455 }
1456}
1457
1458static int __init alloc_buffers(void)
1459{
1460 u32 i, j;
1461
1462 for_each_possible_cpu(i) {
1463 for_each_cpu_buffer(j) {
1464 char *buffer;
1465
1466 if (cpu_to_node(i) > num_online_nodes())
1467 /* fallback to kmalloc for offline nodes */
1468 buffer = kmalloc(aa_g_path_max, GFP_KERNEL);
1469 else
1470 buffer = kmalloc_node(aa_g_path_max, GFP_KERNEL,
1471 cpu_to_node(i));
1472 if (!buffer) {
1473 destroy_buffers();
1474 return -ENOMEM;
1475 }
1476 per_cpu(aa_buffers, i).buf[j] = buffer;
1477 }
1478 }
1479
1480 return 0;
1481}
1482
1483#ifdef CONFIG_SYSCTL
1484static int apparmor_dointvec(struct ctl_table *table, int write,
1485 void __user *buffer, size_t *lenp, loff_t *ppos)
1486{
1487 if (!policy_admin_capable(NULL))
1488 return -EPERM;
1489 if (!apparmor_enabled)
1490 return -EINVAL;
1491
1492 return proc_dointvec(table, write, buffer, lenp, ppos);
1493}
1494
1495static struct ctl_path apparmor_sysctl_path[] = {
1496 { .procname = "kernel", },
1497 { }
1498};
1499
1500static struct ctl_table apparmor_sysctl_table[] = {
1501 {
1502 .procname = "unprivileged_userns_apparmor_policy",
1503 .data = &unprivileged_userns_apparmor_policy,
1504 .maxlen = sizeof(int),
1505 .mode = 0600,
1506 .proc_handler = apparmor_dointvec,
1507 },
1508 { }
1509};
1510
1511static int __init apparmor_init_sysctl(void)
1512{
1513 return register_sysctl_paths(apparmor_sysctl_path,
1514 apparmor_sysctl_table) ? 0 : -ENOMEM;
1515}
1516#else
1517static inline int apparmor_init_sysctl(void)
1518{
1519 return 0;
1520}
1521#endif /* CONFIG_SYSCTL */
1522
1523static int __init apparmor_init(void)
1524{
1525 int error;
1526
1527 if (!apparmor_enabled || !security_module_enable("apparmor")) {
1528 aa_info_message("AppArmor disabled by boot time parameter");
1529 apparmor_enabled = false;
1530 return 0;
1531 }
1532
1533 error = aa_setup_dfa_engine();
1534 if (error) {
1535 AA_ERROR("Unable to setup dfa engine\n");
1536 goto alloc_out;
1537 }
1538
1539 error = aa_alloc_root_ns();
1540 if (error) {
1541 AA_ERROR("Unable to allocate default profile namespace\n");
1542 goto alloc_out;
1543 }
1544
1545 error = apparmor_init_sysctl();
1546 if (error) {
1547 AA_ERROR("Unable to register sysctls\n");
1548 goto alloc_out;
1549
1550 }
1551
1552 error = alloc_buffers();
1553 if (error) {
1554 AA_ERROR("Unable to allocate work buffers\n");
1555 goto buffers_out;
1556 }
1557
1558 error = set_init_ctx();
1559 if (error) {
1560 AA_ERROR("Failed to set context on init task\n");
1561 aa_free_root_ns();
1562 goto buffers_out;
1563 }
1564 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks),
1565 "apparmor");
1566
1567 /* Report that AppArmor successfully initialized */
1568 apparmor_initialized = 1;
1569 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
1570 aa_info_message("AppArmor initialized: complain mode enabled");
1571 else if (aa_g_profile_mode == APPARMOR_KILL)
1572 aa_info_message("AppArmor initialized: kill mode enabled");
1573 else
1574 aa_info_message("AppArmor initialized");
1575
1576 return error;
1577
1578buffers_out:
1579 destroy_buffers();
1580
1581alloc_out:
1582 aa_destroy_aafs();
1583 aa_teardown_dfa_engine();
1584
1585 apparmor_enabled = false;
1586 return error;
1587}
1588
1589security_initcall(apparmor_init);