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