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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/*
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/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 return aa_ptrace(current, child, mode);
100}
101
102static int apparmor_ptrace_traceme(struct task_struct *parent)
103{
104 return aa_ptrace(parent, current, PTRACE_MODE_ATTACH);
105}
106
107/* Derived from security/commoncap.c:cap_capget */
108static int apparmor_capget(struct task_struct *target, kernel_cap_t *effective,
109 kernel_cap_t *inheritable, kernel_cap_t *permitted)
110{
111 struct aa_profile *profile;
112 const struct cred *cred;
113
114 rcu_read_lock();
115 cred = __task_cred(target);
116 profile = aa_cred_profile(cred);
117
118 /*
119 * cap_capget is stacked ahead of this and will
120 * initialize effective and permitted.
121 */
122 if (!unconfined(profile) && !COMPLAIN_MODE(profile)) {
123 *effective = cap_intersect(*effective, profile->caps.allow);
124 *permitted = cap_intersect(*permitted, profile->caps.allow);
125 }
126 rcu_read_unlock();
127
128 return 0;
129}
130
131static int apparmor_capable(const struct cred *cred, struct user_namespace *ns,
132 int cap, int audit)
133{
134 struct aa_profile *profile;
135 int error = 0;
136
137 profile = aa_cred_profile(cred);
138 if (!unconfined(profile))
139 error = aa_capable(profile, cap, audit);
140 return error;
141}
142
143/**
144 * common_perm - basic common permission check wrapper fn for paths
145 * @op: operation being checked
146 * @path: path to check permission of (NOT NULL)
147 * @mask: requested permissions mask
148 * @cond: conditional info for the permission request (NOT NULL)
149 *
150 * Returns: %0 else error code if error or permission denied
151 */
152static int common_perm(int op, const struct path *path, u32 mask,
153 struct path_cond *cond)
154{
155 struct aa_profile *profile;
156 int error = 0;
157
158 profile = __aa_current_profile();
159 if (!unconfined(profile))
160 error = aa_path_perm(op, profile, path, 0, mask, cond);
161
162 return error;
163}
164
165/**
166 * common_perm_dir_dentry - common permission wrapper when path is dir, dentry
167 * @op: operation being checked
168 * @dir: directory of the dentry (NOT NULL)
169 * @dentry: dentry to check (NOT NULL)
170 * @mask: requested permissions mask
171 * @cond: conditional info for the permission request (NOT NULL)
172 *
173 * Returns: %0 else error code if error or permission denied
174 */
175static int common_perm_dir_dentry(int op, const struct path *dir,
176 struct dentry *dentry, u32 mask,
177 struct path_cond *cond)
178{
179 struct path path = { dir->mnt, dentry };
180
181 return common_perm(op, &path, mask, cond);
182}
183
184/**
185 * common_perm_path - common permission wrapper when mnt, dentry
186 * @op: operation being checked
187 * @path: location to check (NOT NULL)
188 * @mask: requested permissions mask
189 *
190 * Returns: %0 else error code if error or permission denied
191 */
192static inline int common_perm_path(int op, const struct path *path, u32 mask)
193{
194 struct path_cond cond = { d_backing_inode(path->dentry)->i_uid,
195 d_backing_inode(path->dentry)->i_mode
196 };
197 if (!mediated_filesystem(path->dentry))
198 return 0;
199
200 return common_perm(op, path, mask, &cond);
201}
202
203/**
204 * common_perm_rm - common permission wrapper for operations doing rm
205 * @op: operation being checked
206 * @dir: directory that the dentry is in (NOT NULL)
207 * @dentry: dentry being rm'd (NOT NULL)
208 * @mask: requested permission mask
209 *
210 * Returns: %0 else error code if error or permission denied
211 */
212static int common_perm_rm(int op, const struct path *dir,
213 struct dentry *dentry, u32 mask)
214{
215 struct inode *inode = d_backing_inode(dentry);
216 struct path_cond cond = { };
217
218 if (!inode || !mediated_filesystem(dentry))
219 return 0;
220
221 cond.uid = inode->i_uid;
222 cond.mode = inode->i_mode;
223
224 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
225}
226
227/**
228 * common_perm_create - common permission wrapper for operations doing create
229 * @op: operation being checked
230 * @dir: directory that dentry will be created in (NOT NULL)
231 * @dentry: dentry to create (NOT NULL)
232 * @mask: request permission mask
233 * @mode: created file mode
234 *
235 * Returns: %0 else error code if error or permission denied
236 */
237static int common_perm_create(int op, const struct path *dir,
238 struct dentry *dentry, u32 mask, umode_t mode)
239{
240 struct path_cond cond = { current_fsuid(), mode };
241
242 if (!mediated_filesystem(dir->dentry))
243 return 0;
244
245 return common_perm_dir_dentry(op, dir, dentry, mask, &cond);
246}
247
248static int apparmor_path_unlink(const struct path *dir, struct dentry *dentry)
249{
250 return common_perm_rm(OP_UNLINK, dir, dentry, AA_MAY_DELETE);
251}
252
253static int apparmor_path_mkdir(const struct path *dir, struct dentry *dentry,
254 umode_t mode)
255{
256 return common_perm_create(OP_MKDIR, dir, dentry, AA_MAY_CREATE,
257 S_IFDIR);
258}
259
260static int apparmor_path_rmdir(const struct path *dir, struct dentry *dentry)
261{
262 return common_perm_rm(OP_RMDIR, dir, dentry, AA_MAY_DELETE);
263}
264
265static int apparmor_path_mknod(const struct path *dir, struct dentry *dentry,
266 umode_t mode, unsigned int dev)
267{
268 return common_perm_create(OP_MKNOD, dir, dentry, AA_MAY_CREATE, mode);
269}
270
271static int apparmor_path_truncate(const struct path *path)
272{
273 return common_perm_path(OP_TRUNC, path, MAY_WRITE | AA_MAY_META_WRITE);
274}
275
276static int apparmor_path_symlink(const struct path *dir, struct dentry *dentry,
277 const char *old_name)
278{
279 return common_perm_create(OP_SYMLINK, dir, dentry, AA_MAY_CREATE,
280 S_IFLNK);
281}
282
283static int apparmor_path_link(struct dentry *old_dentry, const struct path *new_dir,
284 struct dentry *new_dentry)
285{
286 struct aa_profile *profile;
287 int error = 0;
288
289 if (!mediated_filesystem(old_dentry))
290 return 0;
291
292 profile = aa_current_profile();
293 if (!unconfined(profile))
294 error = aa_path_link(profile, old_dentry, new_dir, new_dentry);
295 return error;
296}
297
298static int apparmor_path_rename(const struct path *old_dir, struct dentry *old_dentry,
299 const struct path *new_dir, struct dentry *new_dentry)
300{
301 struct aa_profile *profile;
302 int error = 0;
303
304 if (!mediated_filesystem(old_dentry))
305 return 0;
306
307 profile = aa_current_profile();
308 if (!unconfined(profile)) {
309 struct path old_path = { old_dir->mnt, old_dentry };
310 struct path new_path = { new_dir->mnt, new_dentry };
311 struct path_cond cond = { d_backing_inode(old_dentry)->i_uid,
312 d_backing_inode(old_dentry)->i_mode
313 };
314
315 error = aa_path_perm(OP_RENAME_SRC, profile, &old_path, 0,
316 MAY_READ | AA_MAY_META_READ | MAY_WRITE |
317 AA_MAY_META_WRITE | AA_MAY_DELETE,
318 &cond);
319 if (!error)
320 error = aa_path_perm(OP_RENAME_DEST, profile, &new_path,
321 0, MAY_WRITE | AA_MAY_META_WRITE |
322 AA_MAY_CREATE, &cond);
323
324 }
325 return error;
326}
327
328static int apparmor_path_chmod(const struct path *path, umode_t mode)
329{
330 return common_perm_path(OP_CHMOD, path, AA_MAY_CHMOD);
331}
332
333static int apparmor_path_chown(const struct path *path, kuid_t uid, kgid_t gid)
334{
335 return common_perm_path(OP_CHOWN, path, AA_MAY_CHOWN);
336}
337
338static int apparmor_inode_getattr(const struct path *path)
339{
340 return common_perm_path(OP_GETATTR, path, AA_MAY_META_READ);
341}
342
343static int apparmor_file_open(struct file *file, const struct cred *cred)
344{
345 struct aa_file_cxt *fcxt = file->f_security;
346 struct aa_profile *profile;
347 int error = 0;
348
349 if (!mediated_filesystem(file->f_path.dentry))
350 return 0;
351
352 /* If in exec, permission is handled by bprm hooks.
353 * Cache permissions granted by the previous exec check, with
354 * implicit read and executable mmap which are required to
355 * actually execute the image.
356 */
357 if (current->in_execve) {
358 fcxt->allow = MAY_EXEC | MAY_READ | AA_EXEC_MMAP;
359 return 0;
360 }
361
362 profile = aa_cred_profile(cred);
363 if (!unconfined(profile)) {
364 struct inode *inode = file_inode(file);
365 struct path_cond cond = { inode->i_uid, inode->i_mode };
366
367 error = aa_path_perm(OP_OPEN, profile, &file->f_path, 0,
368 aa_map_file_to_perms(file), &cond);
369 /* todo cache full allowed permissions set and state */
370 fcxt->allow = aa_map_file_to_perms(file);
371 }
372
373 return error;
374}
375
376static int apparmor_file_alloc_security(struct file *file)
377{
378 /* freed by apparmor_file_free_security */
379 file->f_security = aa_alloc_file_context(GFP_KERNEL);
380 if (!file->f_security)
381 return -ENOMEM;
382 return 0;
383
384}
385
386static void apparmor_file_free_security(struct file *file)
387{
388 struct aa_file_cxt *cxt = file->f_security;
389
390 aa_free_file_context(cxt);
391}
392
393static int common_file_perm(int op, struct file *file, u32 mask)
394{
395 struct aa_file_cxt *fcxt = file->f_security;
396 struct aa_profile *profile, *fprofile = aa_cred_profile(file->f_cred);
397 int error = 0;
398
399 BUG_ON(!fprofile);
400
401 if (!file->f_path.mnt ||
402 !mediated_filesystem(file->f_path.dentry))
403 return 0;
404
405 profile = __aa_current_profile();
406
407 /* revalidate access, if task is unconfined, or the cached cred
408 * doesn't match or if the request is for more permissions than
409 * was granted.
410 *
411 * Note: the test for !unconfined(fprofile) is to handle file
412 * delegation from unconfined tasks
413 */
414 if (!unconfined(profile) && !unconfined(fprofile) &&
415 ((fprofile != profile) || (mask & ~fcxt->allow)))
416 error = aa_file_perm(op, profile, file, mask);
417
418 return error;
419}
420
421static int apparmor_file_permission(struct file *file, int mask)
422{
423 return common_file_perm(OP_FPERM, file, mask);
424}
425
426static int apparmor_file_lock(struct file *file, unsigned int cmd)
427{
428 u32 mask = AA_MAY_LOCK;
429
430 if (cmd == F_WRLCK)
431 mask |= MAY_WRITE;
432
433 return common_file_perm(OP_FLOCK, file, mask);
434}
435
436static int common_mmap(int op, struct file *file, unsigned long prot,
437 unsigned long flags)
438{
439 int mask = 0;
440
441 if (!file || !file->f_security)
442 return 0;
443
444 if (prot & PROT_READ)
445 mask |= MAY_READ;
446 /*
447 * Private mappings don't require write perms since they don't
448 * write back to the files
449 */
450 if ((prot & PROT_WRITE) && !(flags & MAP_PRIVATE))
451 mask |= MAY_WRITE;
452 if (prot & PROT_EXEC)
453 mask |= AA_EXEC_MMAP;
454
455 return common_file_perm(op, file, mask);
456}
457
458static int apparmor_mmap_file(struct file *file, unsigned long reqprot,
459 unsigned long prot, unsigned long flags)
460{
461 return common_mmap(OP_FMMAP, file, prot, flags);
462}
463
464static int apparmor_file_mprotect(struct vm_area_struct *vma,
465 unsigned long reqprot, unsigned long prot)
466{
467 return common_mmap(OP_FMPROT, vma->vm_file, prot,
468 !(vma->vm_flags & VM_SHARED) ? MAP_PRIVATE : 0);
469}
470
471static int apparmor_getprocattr(struct task_struct *task, char *name,
472 char **value)
473{
474 int error = -ENOENT;
475 /* released below */
476 const struct cred *cred = get_task_cred(task);
477 struct aa_task_cxt *cxt = cred_cxt(cred);
478 struct aa_profile *profile = NULL;
479
480 if (strcmp(name, "current") == 0)
481 profile = aa_get_newest_profile(cxt->profile);
482 else if (strcmp(name, "prev") == 0 && cxt->previous)
483 profile = aa_get_newest_profile(cxt->previous);
484 else if (strcmp(name, "exec") == 0 && cxt->onexec)
485 profile = aa_get_newest_profile(cxt->onexec);
486 else
487 error = -EINVAL;
488
489 if (profile)
490 error = aa_getprocattr(profile, value);
491
492 aa_put_profile(profile);
493 put_cred(cred);
494
495 return error;
496}
497
498static int apparmor_setprocattr(struct task_struct *task, char *name,
499 void *value, size_t size)
500{
501 struct common_audit_data sa;
502 struct apparmor_audit_data aad = {0,};
503 char *command, *largs = NULL, *args = value;
504 size_t arg_size;
505 int error;
506
507 if (size == 0)
508 return -EINVAL;
509 /* task can only write its own attributes */
510 if (current != task)
511 return -EACCES;
512
513 /* AppArmor requires that the buffer must be null terminated atm */
514 if (args[size - 1] != '\0') {
515 /* null terminate */
516 largs = args = kmalloc(size + 1, GFP_KERNEL);
517 if (!args)
518 return -ENOMEM;
519 memcpy(args, value, size);
520 args[size] = '\0';
521 }
522
523 error = -EINVAL;
524 args = strim(args);
525 command = strsep(&args, " ");
526 if (!args)
527 goto out;
528 args = skip_spaces(args);
529 if (!*args)
530 goto out;
531
532 arg_size = size - (args - (largs ? largs : (char *) value));
533 if (strcmp(name, "current") == 0) {
534 if (strcmp(command, "changehat") == 0) {
535 error = aa_setprocattr_changehat(args, arg_size,
536 !AA_DO_TEST);
537 } else if (strcmp(command, "permhat") == 0) {
538 error = aa_setprocattr_changehat(args, arg_size,
539 AA_DO_TEST);
540 } else if (strcmp(command, "changeprofile") == 0) {
541 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
542 !AA_DO_TEST);
543 } else if (strcmp(command, "permprofile") == 0) {
544 error = aa_setprocattr_changeprofile(args, !AA_ONEXEC,
545 AA_DO_TEST);
546 } else
547 goto fail;
548 } else if (strcmp(name, "exec") == 0) {
549 if (strcmp(command, "exec") == 0)
550 error = aa_setprocattr_changeprofile(args, AA_ONEXEC,
551 !AA_DO_TEST);
552 else
553 goto fail;
554 } else
555 /* only support the "current" and "exec" process attributes */
556 goto fail;
557
558 if (!error)
559 error = size;
560out:
561 kfree(largs);
562 return error;
563
564fail:
565 sa.type = LSM_AUDIT_DATA_NONE;
566 sa.aad = &aad;
567 aad.profile = aa_current_profile();
568 aad.op = OP_SETPROCATTR;
569 aad.info = name;
570 aad.error = error = -EINVAL;
571 aa_audit_msg(AUDIT_APPARMOR_DENIED, &sa, NULL);
572 goto out;
573}
574
575static int apparmor_task_setrlimit(struct task_struct *task,
576 unsigned int resource, struct rlimit *new_rlim)
577{
578 struct aa_profile *profile = __aa_current_profile();
579 int error = 0;
580
581 if (!unconfined(profile))
582 error = aa_task_setrlimit(profile, task, resource, new_rlim);
583
584 return error;
585}
586
587static struct security_hook_list apparmor_hooks[] = {
588 LSM_HOOK_INIT(ptrace_access_check, apparmor_ptrace_access_check),
589 LSM_HOOK_INIT(ptrace_traceme, apparmor_ptrace_traceme),
590 LSM_HOOK_INIT(capget, apparmor_capget),
591 LSM_HOOK_INIT(capable, apparmor_capable),
592
593 LSM_HOOK_INIT(path_link, apparmor_path_link),
594 LSM_HOOK_INIT(path_unlink, apparmor_path_unlink),
595 LSM_HOOK_INIT(path_symlink, apparmor_path_symlink),
596 LSM_HOOK_INIT(path_mkdir, apparmor_path_mkdir),
597 LSM_HOOK_INIT(path_rmdir, apparmor_path_rmdir),
598 LSM_HOOK_INIT(path_mknod, apparmor_path_mknod),
599 LSM_HOOK_INIT(path_rename, apparmor_path_rename),
600 LSM_HOOK_INIT(path_chmod, apparmor_path_chmod),
601 LSM_HOOK_INIT(path_chown, apparmor_path_chown),
602 LSM_HOOK_INIT(path_truncate, apparmor_path_truncate),
603 LSM_HOOK_INIT(inode_getattr, apparmor_inode_getattr),
604
605 LSM_HOOK_INIT(file_open, apparmor_file_open),
606 LSM_HOOK_INIT(file_permission, apparmor_file_permission),
607 LSM_HOOK_INIT(file_alloc_security, apparmor_file_alloc_security),
608 LSM_HOOK_INIT(file_free_security, apparmor_file_free_security),
609 LSM_HOOK_INIT(mmap_file, apparmor_mmap_file),
610 LSM_HOOK_INIT(file_mprotect, apparmor_file_mprotect),
611 LSM_HOOK_INIT(file_lock, apparmor_file_lock),
612
613 LSM_HOOK_INIT(getprocattr, apparmor_getprocattr),
614 LSM_HOOK_INIT(setprocattr, apparmor_setprocattr),
615
616 LSM_HOOK_INIT(cred_alloc_blank, apparmor_cred_alloc_blank),
617 LSM_HOOK_INIT(cred_free, apparmor_cred_free),
618 LSM_HOOK_INIT(cred_prepare, apparmor_cred_prepare),
619 LSM_HOOK_INIT(cred_transfer, apparmor_cred_transfer),
620
621 LSM_HOOK_INIT(bprm_set_creds, apparmor_bprm_set_creds),
622 LSM_HOOK_INIT(bprm_committing_creds, apparmor_bprm_committing_creds),
623 LSM_HOOK_INIT(bprm_committed_creds, apparmor_bprm_committed_creds),
624 LSM_HOOK_INIT(bprm_secureexec, apparmor_bprm_secureexec),
625
626 LSM_HOOK_INIT(task_setrlimit, apparmor_task_setrlimit),
627};
628
629/*
630 * AppArmor sysfs module parameters
631 */
632
633static int param_set_aabool(const char *val, const struct kernel_param *kp);
634static int param_get_aabool(char *buffer, const struct kernel_param *kp);
635#define param_check_aabool param_check_bool
636static const struct kernel_param_ops param_ops_aabool = {
637 .flags = KERNEL_PARAM_OPS_FL_NOARG,
638 .set = param_set_aabool,
639 .get = param_get_aabool
640};
641
642static int param_set_aauint(const char *val, const struct kernel_param *kp);
643static int param_get_aauint(char *buffer, const struct kernel_param *kp);
644#define param_check_aauint param_check_uint
645static const struct kernel_param_ops param_ops_aauint = {
646 .set = param_set_aauint,
647 .get = param_get_aauint
648};
649
650static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp);
651static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp);
652#define param_check_aalockpolicy param_check_bool
653static const struct kernel_param_ops param_ops_aalockpolicy = {
654 .flags = KERNEL_PARAM_OPS_FL_NOARG,
655 .set = param_set_aalockpolicy,
656 .get = param_get_aalockpolicy
657};
658
659static int param_set_audit(const char *val, struct kernel_param *kp);
660static int param_get_audit(char *buffer, struct kernel_param *kp);
661
662static int param_set_mode(const char *val, struct kernel_param *kp);
663static int param_get_mode(char *buffer, struct kernel_param *kp);
664
665/* Flag values, also controllable via /sys/module/apparmor/parameters
666 * We define special types as we want to do additional mediation.
667 */
668
669/* AppArmor global enforcement switch - complain, enforce, kill */
670enum profile_mode aa_g_profile_mode = APPARMOR_ENFORCE;
671module_param_call(mode, param_set_mode, param_get_mode,
672 &aa_g_profile_mode, S_IRUSR | S_IWUSR);
673
674#ifdef CONFIG_SECURITY_APPARMOR_HASH
675/* whether policy verification hashing is enabled */
676bool aa_g_hash_policy = IS_ENABLED(CONFIG_SECURITY_APPARMOR_HASH_DEFAULT);
677module_param_named(hash_policy, aa_g_hash_policy, aabool, S_IRUSR | S_IWUSR);
678#endif
679
680/* Debug mode */
681bool aa_g_debug;
682module_param_named(debug, aa_g_debug, aabool, S_IRUSR | S_IWUSR);
683
684/* Audit mode */
685enum audit_mode aa_g_audit;
686module_param_call(audit, param_set_audit, param_get_audit,
687 &aa_g_audit, S_IRUSR | S_IWUSR);
688
689/* Determines if audit header is included in audited messages. This
690 * provides more context if the audit daemon is not running
691 */
692bool aa_g_audit_header = 1;
693module_param_named(audit_header, aa_g_audit_header, aabool,
694 S_IRUSR | S_IWUSR);
695
696/* lock out loading/removal of policy
697 * TODO: add in at boot loading of policy, which is the only way to
698 * load policy, if lock_policy is set
699 */
700bool aa_g_lock_policy;
701module_param_named(lock_policy, aa_g_lock_policy, aalockpolicy,
702 S_IRUSR | S_IWUSR);
703
704/* Syscall logging mode */
705bool aa_g_logsyscall;
706module_param_named(logsyscall, aa_g_logsyscall, aabool, S_IRUSR | S_IWUSR);
707
708/* Maximum pathname length before accesses will start getting rejected */
709unsigned int aa_g_path_max = 2 * PATH_MAX;
710module_param_named(path_max, aa_g_path_max, aauint, S_IRUSR | S_IWUSR);
711
712/* Determines how paranoid loading of policy is and how much verification
713 * on the loaded policy is done.
714 */
715bool aa_g_paranoid_load = 1;
716module_param_named(paranoid_load, aa_g_paranoid_load, aabool,
717 S_IRUSR | S_IWUSR);
718
719/* Boot time disable flag */
720static bool apparmor_enabled = CONFIG_SECURITY_APPARMOR_BOOTPARAM_VALUE;
721module_param_named(enabled, apparmor_enabled, bool, S_IRUGO);
722
723static int __init apparmor_enabled_setup(char *str)
724{
725 unsigned long enabled;
726 int error = kstrtoul(str, 0, &enabled);
727 if (!error)
728 apparmor_enabled = enabled ? 1 : 0;
729 return 1;
730}
731
732__setup("apparmor=", apparmor_enabled_setup);
733
734/* set global flag turning off the ability to load policy */
735static int param_set_aalockpolicy(const char *val, const struct kernel_param *kp)
736{
737 if (!policy_admin_capable())
738 return -EPERM;
739 return param_set_bool(val, kp);
740}
741
742static int param_get_aalockpolicy(char *buffer, const struct kernel_param *kp)
743{
744 if (!policy_view_capable())
745 return -EPERM;
746 return param_get_bool(buffer, kp);
747}
748
749static int param_set_aabool(const char *val, const struct kernel_param *kp)
750{
751 if (!policy_admin_capable())
752 return -EPERM;
753 return param_set_bool(val, kp);
754}
755
756static int param_get_aabool(char *buffer, const struct kernel_param *kp)
757{
758 if (!policy_view_capable())
759 return -EPERM;
760 return param_get_bool(buffer, kp);
761}
762
763static int param_set_aauint(const char *val, const struct kernel_param *kp)
764{
765 if (!policy_admin_capable())
766 return -EPERM;
767 return param_set_uint(val, kp);
768}
769
770static int param_get_aauint(char *buffer, const struct kernel_param *kp)
771{
772 if (!policy_view_capable())
773 return -EPERM;
774 return param_get_uint(buffer, kp);
775}
776
777static int param_get_audit(char *buffer, struct kernel_param *kp)
778{
779 if (!policy_view_capable())
780 return -EPERM;
781
782 if (!apparmor_enabled)
783 return -EINVAL;
784
785 return sprintf(buffer, "%s", audit_mode_names[aa_g_audit]);
786}
787
788static int param_set_audit(const char *val, struct kernel_param *kp)
789{
790 int i;
791 if (!policy_admin_capable())
792 return -EPERM;
793
794 if (!apparmor_enabled)
795 return -EINVAL;
796
797 if (!val)
798 return -EINVAL;
799
800 for (i = 0; i < AUDIT_MAX_INDEX; i++) {
801 if (strcmp(val, audit_mode_names[i]) == 0) {
802 aa_g_audit = i;
803 return 0;
804 }
805 }
806
807 return -EINVAL;
808}
809
810static int param_get_mode(char *buffer, struct kernel_param *kp)
811{
812 if (!policy_admin_capable())
813 return -EPERM;
814
815 if (!apparmor_enabled)
816 return -EINVAL;
817
818 return sprintf(buffer, "%s", aa_profile_mode_names[aa_g_profile_mode]);
819}
820
821static int param_set_mode(const char *val, struct kernel_param *kp)
822{
823 int i;
824 if (!policy_admin_capable())
825 return -EPERM;
826
827 if (!apparmor_enabled)
828 return -EINVAL;
829
830 if (!val)
831 return -EINVAL;
832
833 for (i = 0; i < APPARMOR_MODE_NAMES_MAX_INDEX; i++) {
834 if (strcmp(val, aa_profile_mode_names[i]) == 0) {
835 aa_g_profile_mode = i;
836 return 0;
837 }
838 }
839
840 return -EINVAL;
841}
842
843/*
844 * AppArmor init functions
845 */
846
847/**
848 * set_init_cxt - set a task context and profile on the first task.
849 *
850 * TODO: allow setting an alternate profile than unconfined
851 */
852static int __init set_init_cxt(void)
853{
854 struct cred *cred = (struct cred *)current->real_cred;
855 struct aa_task_cxt *cxt;
856
857 cxt = aa_alloc_task_context(GFP_KERNEL);
858 if (!cxt)
859 return -ENOMEM;
860
861 cxt->profile = aa_get_profile(root_ns->unconfined);
862 cred_cxt(cred) = cxt;
863
864 return 0;
865}
866
867static int __init apparmor_init(void)
868{
869 int error;
870
871 if (!apparmor_enabled || !security_module_enable("apparmor")) {
872 aa_info_message("AppArmor disabled by boot time parameter");
873 apparmor_enabled = 0;
874 return 0;
875 }
876
877 error = aa_alloc_root_ns();
878 if (error) {
879 AA_ERROR("Unable to allocate default profile namespace\n");
880 goto alloc_out;
881 }
882
883 error = set_init_cxt();
884 if (error) {
885 AA_ERROR("Failed to set context on init task\n");
886 aa_free_root_ns();
887 goto alloc_out;
888 }
889 security_add_hooks(apparmor_hooks, ARRAY_SIZE(apparmor_hooks));
890
891 /* Report that AppArmor successfully initialized */
892 apparmor_initialized = 1;
893 if (aa_g_profile_mode == APPARMOR_COMPLAIN)
894 aa_info_message("AppArmor initialized: complain mode enabled");
895 else if (aa_g_profile_mode == APPARMOR_KILL)
896 aa_info_message("AppArmor initialized: kill mode enabled");
897 else
898 aa_info_message("AppArmor initialized");
899
900 return error;
901
902alloc_out:
903 aa_destroy_aafs();
904
905 apparmor_enabled = 0;
906 return error;
907}
908
909security_initcall(apparmor_init);