2 * AppArmor security module
4 * This file contains AppArmor /sys/kernel/security/apparmor interface functions
6 * Copyright (C) 1998-2008 Novell/SUSE
7 * Copyright 2009-2010 Canonical Ltd.
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
15 #include <linux/ctype.h>
16 #include <linux/security.h>
17 #include <linux/vmalloc.h>
18 #include <linux/module.h>
19 #include <linux/seq_file.h>
20 #include <linux/uaccess.h>
21 #include <linux/namei.h>
22 #include <linux/capability.h>
23 #include <linux/rcupdate.h>
25 #include "include/apparmor.h"
26 #include "include/apparmorfs.h"
27 #include "include/audit.h"
28 #include "include/context.h"
29 #include "include/crypto.h"
30 #include "include/policy.h"
31 #include "include/resource.h"
34 * aa_mangle_name - mangle a profile name to std profile layout form
35 * @name: profile name to mangle (NOT NULL)
36 * @target: buffer to store mangled name, same length as @name (MAYBE NULL)
38 * Returns: length of mangled name
40 static int mangle_name(char *name, char *target)
44 while (*name == '/' || *name == '.')
48 for (; *name; name++) {
51 else if (isspace(*name))
53 else if (isalnum(*name) || strchr("._-", *name))
60 for (; *name; name++) {
61 if (isalnum(*name) || isspace(*name) ||
62 strchr("/._-", *name))
73 * aa_simple_write_to_buffer - common routine for getting policy from user
74 * @op: operation doing the user buffer copy
75 * @userbuf: user buffer to copy data from (NOT NULL)
76 * @alloc_size: size of user buffer (REQUIRES: @alloc_size >= @copy_size)
77 * @copy_size: size of data to copy from user buffer
78 * @pos: position write is at in the file (NOT NULL)
80 * Returns: kernel buffer containing copy of user buffer data or an
83 static char *aa_simple_write_to_buffer(int op, const char __user *userbuf,
84 size_t alloc_size, size_t copy_size,
89 BUG_ON(copy_size > alloc_size);
92 /* only writes from pos 0, that is complete writes */
93 return ERR_PTR(-ESPIPE);
96 * Don't allow profile load/replace/remove from profiles that don't
99 if (!aa_may_manage_policy(op))
100 return ERR_PTR(-EACCES);
102 /* freed by caller to simple_write_to_buffer */
103 data = kvmalloc(alloc_size);
105 return ERR_PTR(-ENOMEM);
107 if (copy_from_user(data, userbuf, copy_size)) {
109 return ERR_PTR(-EFAULT);
116 /* .load file hook fn to load policy */
117 static ssize_t profile_load(struct file *f, const char __user *buf, size_t size,
123 data = aa_simple_write_to_buffer(OP_PROF_LOAD, buf, size, size, pos);
125 error = PTR_ERR(data);
127 error = aa_replace_profiles(data, size, PROF_ADD);
134 static const struct file_operations aa_fs_profile_load = {
135 .write = profile_load,
136 .llseek = default_llseek,
139 /* .replace file hook fn to load and/or replace policy */
140 static ssize_t profile_replace(struct file *f, const char __user *buf,
141 size_t size, loff_t *pos)
146 data = aa_simple_write_to_buffer(OP_PROF_REPL, buf, size, size, pos);
147 error = PTR_ERR(data);
149 error = aa_replace_profiles(data, size, PROF_REPLACE);
156 static const struct file_operations aa_fs_profile_replace = {
157 .write = profile_replace,
158 .llseek = default_llseek,
161 /* .remove file hook fn to remove loaded policy */
162 static ssize_t profile_remove(struct file *f, const char __user *buf,
163 size_t size, loff_t *pos)
169 * aa_remove_profile needs a null terminated string so 1 extra
170 * byte is allocated and the copied data is null terminated.
172 data = aa_simple_write_to_buffer(OP_PROF_RM, buf, size + 1, size, pos);
174 error = PTR_ERR(data);
177 error = aa_remove_profiles(data, size);
184 static const struct file_operations aa_fs_profile_remove = {
185 .write = profile_remove,
186 .llseek = default_llseek,
189 static int aa_fs_seq_show(struct seq_file *seq, void *v)
191 struct aa_fs_entry *fs_file = seq->private;
196 switch (fs_file->v_type) {
197 case AA_FS_TYPE_BOOLEAN:
198 seq_printf(seq, "%s\n", fs_file->v.boolean ? "yes" : "no");
200 case AA_FS_TYPE_STRING:
201 seq_printf(seq, "%s\n", fs_file->v.string);
204 seq_printf(seq, "%#08lx\n", fs_file->v.u64);
207 /* Ignore unpritable entry types. */
214 static int aa_fs_seq_open(struct inode *inode, struct file *file)
216 return single_open(file, aa_fs_seq_show, inode->i_private);
219 const struct file_operations aa_fs_seq_file_ops = {
220 .owner = THIS_MODULE,
221 .open = aa_fs_seq_open,
224 .release = single_release,
227 static int aa_fs_seq_profile_open(struct inode *inode, struct file *file,
228 int (*show)(struct seq_file *, void *))
230 struct aa_replacedby *r = aa_get_replacedby(inode->i_private);
231 int error = single_open(file, show, r);
234 file->private_data = NULL;
235 aa_put_replacedby(r);
241 static int aa_fs_seq_profile_release(struct inode *inode, struct file *file)
243 struct seq_file *seq = (struct seq_file *) file->private_data;
245 aa_put_replacedby(seq->private);
246 return single_release(inode, file);
249 static int aa_fs_seq_profname_show(struct seq_file *seq, void *v)
251 struct aa_replacedby *r = seq->private;
252 struct aa_profile *profile = aa_get_profile_rcu(&r->profile);
253 seq_printf(seq, "%s\n", profile->base.name);
254 aa_put_profile(profile);
259 static int aa_fs_seq_profname_open(struct inode *inode, struct file *file)
261 return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profname_show);
264 static const struct file_operations aa_fs_profname_fops = {
265 .owner = THIS_MODULE,
266 .open = aa_fs_seq_profname_open,
269 .release = aa_fs_seq_profile_release,
272 static int aa_fs_seq_profmode_show(struct seq_file *seq, void *v)
274 struct aa_replacedby *r = seq->private;
275 struct aa_profile *profile = aa_get_profile_rcu(&r->profile);
276 seq_printf(seq, "%s\n", aa_profile_mode_names[profile->mode]);
277 aa_put_profile(profile);
282 static int aa_fs_seq_profmode_open(struct inode *inode, struct file *file)
284 return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profmode_show);
287 static const struct file_operations aa_fs_profmode_fops = {
288 .owner = THIS_MODULE,
289 .open = aa_fs_seq_profmode_open,
292 .release = aa_fs_seq_profile_release,
295 static int aa_fs_seq_profattach_show(struct seq_file *seq, void *v)
297 struct aa_replacedby *r = seq->private;
298 struct aa_profile *profile = aa_get_profile_rcu(&r->profile);
300 seq_printf(seq, "%s\n", profile->attach);
301 else if (profile->xmatch)
302 seq_puts(seq, "<unknown>\n");
304 seq_printf(seq, "%s\n", profile->base.name);
305 aa_put_profile(profile);
310 static int aa_fs_seq_profattach_open(struct inode *inode, struct file *file)
312 return aa_fs_seq_profile_open(inode, file, aa_fs_seq_profattach_show);
315 static const struct file_operations aa_fs_profattach_fops = {
316 .owner = THIS_MODULE,
317 .open = aa_fs_seq_profattach_open,
320 .release = aa_fs_seq_profile_release,
323 static int aa_fs_seq_hash_show(struct seq_file *seq, void *v)
325 struct aa_replacedby *r = seq->private;
326 struct aa_profile *profile = aa_get_profile_rcu(&r->profile);
327 unsigned int i, size = aa_hash_size();
330 for (i = 0; i < size; i++)
331 seq_printf(seq, "%.2x", profile->hash[i]);
334 aa_put_profile(profile);
339 static int aa_fs_seq_hash_open(struct inode *inode, struct file *file)
341 return single_open(file, aa_fs_seq_hash_show, inode->i_private);
344 static const struct file_operations aa_fs_seq_hash_fops = {
345 .owner = THIS_MODULE,
346 .open = aa_fs_seq_hash_open,
349 .release = single_release,
352 /** fns to setup dynamic per profile/namespace files **/
353 void __aa_fs_profile_rmdir(struct aa_profile *profile)
355 struct aa_profile *child;
361 list_for_each_entry(child, &profile->base.profiles, base.list)
362 __aa_fs_profile_rmdir(child);
364 for (i = AAFS_PROF_SIZEOF - 1; i >= 0; --i) {
365 struct aa_replacedby *r;
366 if (!profile->dents[i])
369 r = d_inode(profile->dents[i])->i_private;
370 securityfs_remove(profile->dents[i]);
371 aa_put_replacedby(r);
372 profile->dents[i] = NULL;
376 void __aa_fs_profile_migrate_dents(struct aa_profile *old,
377 struct aa_profile *new)
381 for (i = 0; i < AAFS_PROF_SIZEOF; i++) {
382 new->dents[i] = old->dents[i];
384 new->dents[i]->d_inode->i_mtime = CURRENT_TIME;
385 old->dents[i] = NULL;
389 static struct dentry *create_profile_file(struct dentry *dir, const char *name,
390 struct aa_profile *profile,
391 const struct file_operations *fops)
393 struct aa_replacedby *r = aa_get_replacedby(profile->replacedby);
396 dent = securityfs_create_file(name, S_IFREG | 0444, dir, r, fops);
398 aa_put_replacedby(r);
403 /* requires lock be held */
404 int __aa_fs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
406 struct aa_profile *child;
407 struct dentry *dent = NULL, *dir;
411 struct aa_profile *p;
412 p = aa_deref_parent(profile);
414 /* adding to parent that previously didn't have children */
415 dent = securityfs_create_dir("profiles", dent);
418 prof_child_dir(p) = parent = dent;
421 if (!profile->dirname) {
423 len = mangle_name(profile->base.name, NULL);
424 id_len = snprintf(NULL, 0, ".%ld", profile->ns->uniq_id);
426 profile->dirname = kmalloc(len + id_len + 1, GFP_KERNEL);
427 if (!profile->dirname)
430 mangle_name(profile->base.name, profile->dirname);
431 sprintf(profile->dirname + len, ".%ld", profile->ns->uniq_id++);
434 dent = securityfs_create_dir(profile->dirname, parent);
437 prof_dir(profile) = dir = dent;
439 dent = create_profile_file(dir, "name", profile, &aa_fs_profname_fops);
442 profile->dents[AAFS_PROF_NAME] = dent;
444 dent = create_profile_file(dir, "mode", profile, &aa_fs_profmode_fops);
447 profile->dents[AAFS_PROF_MODE] = dent;
449 dent = create_profile_file(dir, "attach", profile,
450 &aa_fs_profattach_fops);
453 profile->dents[AAFS_PROF_ATTACH] = dent;
456 dent = create_profile_file(dir, "sha1", profile,
457 &aa_fs_seq_hash_fops);
460 profile->dents[AAFS_PROF_HASH] = dent;
463 list_for_each_entry(child, &profile->base.profiles, base.list) {
464 error = __aa_fs_profile_mkdir(child, prof_child_dir(profile));
472 error = PTR_ERR(dent);
475 __aa_fs_profile_rmdir(profile);
480 void __aa_fs_namespace_rmdir(struct aa_namespace *ns)
482 struct aa_namespace *sub;
483 struct aa_profile *child;
489 list_for_each_entry(child, &ns->base.profiles, base.list)
490 __aa_fs_profile_rmdir(child);
492 list_for_each_entry(sub, &ns->sub_ns, base.list) {
493 mutex_lock(&sub->lock);
494 __aa_fs_namespace_rmdir(sub);
495 mutex_unlock(&sub->lock);
498 for (i = AAFS_NS_SIZEOF - 1; i >= 0; --i) {
499 securityfs_remove(ns->dents[i]);
504 int __aa_fs_namespace_mkdir(struct aa_namespace *ns, struct dentry *parent,
507 struct aa_namespace *sub;
508 struct aa_profile *child;
509 struct dentry *dent, *dir;
513 name = ns->base.name;
515 dent = securityfs_create_dir(name, parent);
518 ns_dir(ns) = dir = dent;
520 dent = securityfs_create_dir("profiles", dir);
523 ns_subprofs_dir(ns) = dent;
525 dent = securityfs_create_dir("namespaces", dir);
528 ns_subns_dir(ns) = dent;
530 list_for_each_entry(child, &ns->base.profiles, base.list) {
531 error = __aa_fs_profile_mkdir(child, ns_subprofs_dir(ns));
536 list_for_each_entry(sub, &ns->sub_ns, base.list) {
537 mutex_lock(&sub->lock);
538 error = __aa_fs_namespace_mkdir(sub, ns_subns_dir(ns), NULL);
539 mutex_unlock(&sub->lock);
547 error = PTR_ERR(dent);
550 __aa_fs_namespace_rmdir(ns);
556 #define list_entry_next(pos, member) \
557 list_entry(pos->member.next, typeof(*pos), member)
558 #define list_entry_is_head(pos, head, member) (&pos->member == (head))
561 * __next_namespace - find the next namespace to list
562 * @root: root namespace to stop search at (NOT NULL)
563 * @ns: current ns position (NOT NULL)
565 * Find the next namespace from @ns under @root and handle all locking needed
566 * while switching current namespace.
568 * Returns: next namespace or NULL if at last namespace under @root
569 * Requires: ns->parent->lock to be held
570 * NOTE: will not unlock root->lock
572 static struct aa_namespace *__next_namespace(struct aa_namespace *root,
573 struct aa_namespace *ns)
575 struct aa_namespace *parent, *next;
577 /* is next namespace a child */
578 if (!list_empty(&ns->sub_ns)) {
579 next = list_first_entry(&ns->sub_ns, typeof(*ns), base.list);
580 mutex_lock(&next->lock);
584 /* check if the next ns is a sibling, parent, gp, .. */
587 mutex_unlock(&ns->lock);
588 next = list_entry_next(ns, base.list);
589 if (!list_entry_is_head(next, &parent->sub_ns, base.list)) {
590 mutex_lock(&next->lock);
594 parent = parent->parent;
601 * __first_profile - find the first profile in a namespace
602 * @root: namespace that is root of profiles being displayed (NOT NULL)
603 * @ns: namespace to start in (NOT NULL)
605 * Returns: unrefcounted profile or NULL if no profile
606 * Requires: profile->ns.lock to be held
608 static struct aa_profile *__first_profile(struct aa_namespace *root,
609 struct aa_namespace *ns)
611 for (; ns; ns = __next_namespace(root, ns)) {
612 if (!list_empty(&ns->base.profiles))
613 return list_first_entry(&ns->base.profiles,
614 struct aa_profile, base.list);
620 * __next_profile - step to the next profile in a profile tree
621 * @profile: current profile in tree (NOT NULL)
623 * Perform a depth first traversal on the profile tree in a namespace
625 * Returns: next profile or NULL if done
626 * Requires: profile->ns.lock to be held
628 static struct aa_profile *__next_profile(struct aa_profile *p)
630 struct aa_profile *parent;
631 struct aa_namespace *ns = p->ns;
633 /* is next profile a child */
634 if (!list_empty(&p->base.profiles))
635 return list_first_entry(&p->base.profiles, typeof(*p),
638 /* is next profile a sibling, parent sibling, gp, sibling, .. */
639 parent = rcu_dereference_protected(p->parent,
640 mutex_is_locked(&p->ns->lock));
642 p = list_entry_next(p, base.list);
643 if (!list_entry_is_head(p, &parent->base.profiles, base.list))
646 parent = rcu_dereference_protected(parent->parent,
647 mutex_is_locked(&parent->ns->lock));
650 /* is next another profile in the namespace */
651 p = list_entry_next(p, base.list);
652 if (!list_entry_is_head(p, &ns->base.profiles, base.list))
659 * next_profile - step to the next profile in where ever it may be
660 * @root: root namespace (NOT NULL)
661 * @profile: current profile (NOT NULL)
663 * Returns: next profile or NULL if there isn't one
665 static struct aa_profile *next_profile(struct aa_namespace *root,
666 struct aa_profile *profile)
668 struct aa_profile *next = __next_profile(profile);
672 /* finished all profiles in namespace move to next namespace */
673 return __first_profile(root, __next_namespace(root, profile->ns));
677 * p_start - start a depth first traversal of profile tree
678 * @f: seq_file to fill
679 * @pos: current position
681 * Returns: first profile under current namespace or NULL if none found
683 * acquires first ns->lock
685 static void *p_start(struct seq_file *f, loff_t *pos)
687 struct aa_profile *profile = NULL;
688 struct aa_namespace *root = aa_current_profile()->ns;
690 f->private = aa_get_namespace(root);
693 /* find the first profile */
694 mutex_lock(&root->lock);
695 profile = __first_profile(root, root);
697 /* skip to position */
698 for (; profile && l > 0; l--)
699 profile = next_profile(root, profile);
705 * p_next - read the next profile entry
706 * @f: seq_file to fill
707 * @p: profile previously returned
708 * @pos: current position
710 * Returns: next profile after @p or NULL if none
712 * may acquire/release locks in namespace tree as necessary
714 static void *p_next(struct seq_file *f, void *p, loff_t *pos)
716 struct aa_profile *profile = p;
717 struct aa_namespace *ns = f->private;
720 return next_profile(ns, profile);
724 * p_stop - stop depth first traversal
725 * @f: seq_file we are filling
726 * @p: the last profile writen
728 * Release all locking done by p_start/p_next on namespace tree
730 static void p_stop(struct seq_file *f, void *p)
732 struct aa_profile *profile = p;
733 struct aa_namespace *root = f->private, *ns;
736 for (ns = profile->ns; ns && ns != root; ns = ns->parent)
737 mutex_unlock(&ns->lock);
739 mutex_unlock(&root->lock);
740 aa_put_namespace(root);
744 * seq_show_profile - show a profile entry
745 * @f: seq_file to file
746 * @p: current position (profile) (NOT NULL)
748 * Returns: error on failure
750 static int seq_show_profile(struct seq_file *f, void *p)
752 struct aa_profile *profile = (struct aa_profile *)p;
753 struct aa_namespace *root = f->private;
755 if (profile->ns != root)
756 seq_printf(f, ":%s://", aa_ns_name(root, profile->ns));
757 seq_printf(f, "%s (%s)\n", profile->base.hname,
758 aa_profile_mode_names[profile->mode]);
763 static const struct seq_operations aa_fs_profiles_op = {
767 .show = seq_show_profile,
770 static int profiles_open(struct inode *inode, struct file *file)
772 return seq_open(file, &aa_fs_profiles_op);
775 static int profiles_release(struct inode *inode, struct file *file)
777 return seq_release(inode, file);
780 static const struct file_operations aa_fs_profiles_fops = {
781 .open = profiles_open,
784 .release = profiles_release,
788 /** Base file system setup **/
789 static struct aa_fs_entry aa_fs_entry_file[] = {
790 AA_FS_FILE_STRING("mask", "create read write exec append mmap_exec " \
795 static struct aa_fs_entry aa_fs_entry_domain[] = {
796 AA_FS_FILE_BOOLEAN("change_hat", 1),
797 AA_FS_FILE_BOOLEAN("change_hatv", 1),
798 AA_FS_FILE_BOOLEAN("change_onexec", 1),
799 AA_FS_FILE_BOOLEAN("change_profile", 1),
803 static struct aa_fs_entry aa_fs_entry_policy[] = {
804 AA_FS_FILE_BOOLEAN("set_load", 1),
808 static struct aa_fs_entry aa_fs_entry_features[] = {
809 AA_FS_DIR("policy", aa_fs_entry_policy),
810 AA_FS_DIR("domain", aa_fs_entry_domain),
811 AA_FS_DIR("file", aa_fs_entry_file),
812 AA_FS_FILE_U64("capability", VFS_CAP_FLAGS_MASK),
813 AA_FS_DIR("rlimit", aa_fs_entry_rlimit),
814 AA_FS_DIR("caps", aa_fs_entry_caps),
818 static struct aa_fs_entry aa_fs_entry_apparmor[] = {
819 AA_FS_FILE_FOPS(".load", 0640, &aa_fs_profile_load),
820 AA_FS_FILE_FOPS(".replace", 0640, &aa_fs_profile_replace),
821 AA_FS_FILE_FOPS(".remove", 0640, &aa_fs_profile_remove),
822 AA_FS_FILE_FOPS("profiles", 0640, &aa_fs_profiles_fops),
823 AA_FS_DIR("features", aa_fs_entry_features),
827 static struct aa_fs_entry aa_fs_entry =
828 AA_FS_DIR("apparmor", aa_fs_entry_apparmor);
831 * aafs_create_file - create a file entry in the apparmor securityfs
832 * @fs_file: aa_fs_entry to build an entry for (NOT NULL)
833 * @parent: the parent dentry in the securityfs
835 * Use aafs_remove_file to remove entries created with this fn.
837 static int __init aafs_create_file(struct aa_fs_entry *fs_file,
838 struct dentry *parent)
842 fs_file->dentry = securityfs_create_file(fs_file->name,
843 S_IFREG | fs_file->mode,
846 if (IS_ERR(fs_file->dentry)) {
847 error = PTR_ERR(fs_file->dentry);
848 fs_file->dentry = NULL;
853 static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir);
855 * aafs_create_dir - recursively create a directory entry in the securityfs
856 * @fs_dir: aa_fs_entry (and all child entries) to build (NOT NULL)
857 * @parent: the parent dentry in the securityfs
859 * Use aafs_remove_dir to remove entries created with this fn.
861 static int __init aafs_create_dir(struct aa_fs_entry *fs_dir,
862 struct dentry *parent)
864 struct aa_fs_entry *fs_file;
868 dir = securityfs_create_dir(fs_dir->name, parent);
871 fs_dir->dentry = dir;
873 for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) {
874 if (fs_file->v_type == AA_FS_TYPE_DIR)
875 error = aafs_create_dir(fs_file, fs_dir->dentry);
877 error = aafs_create_file(fs_file, fs_dir->dentry);
885 aafs_remove_dir(fs_dir);
891 * aafs_remove_file - drop a single file entry in the apparmor securityfs
892 * @fs_file: aa_fs_entry to detach from the securityfs (NOT NULL)
894 static void __init aafs_remove_file(struct aa_fs_entry *fs_file)
896 if (!fs_file->dentry)
899 securityfs_remove(fs_file->dentry);
900 fs_file->dentry = NULL;
904 * aafs_remove_dir - recursively drop a directory entry from the securityfs
905 * @fs_dir: aa_fs_entry (and all child entries) to detach (NOT NULL)
907 static void __init aafs_remove_dir(struct aa_fs_entry *fs_dir)
909 struct aa_fs_entry *fs_file;
911 for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) {
912 if (fs_file->v_type == AA_FS_TYPE_DIR)
913 aafs_remove_dir(fs_file);
915 aafs_remove_file(fs_file);
918 aafs_remove_file(fs_dir);
922 * aa_destroy_aafs - cleanup and free aafs
924 * releases dentries allocated by aa_create_aafs
926 void __init aa_destroy_aafs(void)
928 aafs_remove_dir(&aa_fs_entry);
932 * aa_create_aafs - create the apparmor security filesystem
934 * dentries created here are released by aa_destroy_aafs
936 * Returns: error on failure
938 static int __init aa_create_aafs(void)
942 if (!apparmor_initialized)
945 if (aa_fs_entry.dentry) {
946 AA_ERROR("%s: AppArmor securityfs already exists\n", __func__);
950 /* Populate fs tree. */
951 error = aafs_create_dir(&aa_fs_entry, NULL);
955 error = __aa_fs_namespace_mkdir(root_ns, aa_fs_entry.dentry,
960 /* TODO: add support for apparmorfs_null and apparmorfs_mnt */
962 /* Report that AppArmor fs is enabled */
963 aa_info_message("AppArmor Filesystem Enabled");
968 AA_ERROR("Error creating AppArmor securityfs\n");
972 fs_initcall(aa_create_aafs);