1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * AppArmor security module
4 *
5 * This file contains AppArmor /sys/kernel/security/apparmor interface functions
6 *
7 * Copyright (C) 1998-2008 Novell/SUSE
8 * Copyright 2009-2010 Canonical Ltd.
9 */
10
11 #include <linux/ctype.h>
12 #include <linux/security.h>
13 #include <linux/vmalloc.h>
14 #include <linux/init.h>
15 #include <linux/seq_file.h>
16 #include <linux/uaccess.h>
17 #include <linux/mount.h>
18 #include <linux/namei.h>
19 #include <linux/capability.h>
20 #include <linux/rcupdate.h>
21 #include <linux/fs.h>
22 #include <linux/fs_context.h>
23 #include <linux/poll.h>
24 #include <linux/zlib.h>
25 #include <uapi/linux/major.h>
26 #include <uapi/linux/magic.h>
27
28 #include "include/apparmor.h"
29 #include "include/apparmorfs.h"
30 #include "include/audit.h"
31 #include "include/cred.h"
32 #include "include/crypto.h"
33 #include "include/ipc.h"
34 #include "include/label.h"
35 #include "include/policy.h"
36 #include "include/policy_ns.h"
37 #include "include/resource.h"
38 #include "include/policy_unpack.h"
39
40 /*
41 * The apparmor filesystem interface used for policy load and introspection
42 * The interface is split into two main components based on their function
43 * a securityfs component:
44 * used for static files that are always available, and which allows
45 * userspace to specificy the location of the security filesystem.
46 *
47 * fns and data are prefixed with
48 * aa_sfs_
49 *
50 * an apparmorfs component:
51 * used loaded policy content and introspection. It is not part of a
52 * regular mounted filesystem and is available only through the magic
53 * policy symlink in the root of the securityfs apparmor/ directory.
54 * Tasks queries will be magically redirected to the correct portion
55 * of the policy tree based on their confinement.
56 *
57 * fns and data are prefixed with
58 * aafs_
59 *
60 * The aa_fs_ prefix is used to indicate the fn is used by both the
61 * securityfs and apparmorfs filesystems.
62 */
63
64
65 /*
66 * support fns
67 */
68
69 struct rawdata_f_data {
70 struct aa_loaddata *loaddata;
71 };
72
73 #define RAWDATA_F_DATA_BUF(p) (char *)(p + 1)
74
rawdata_f_data_free(struct rawdata_f_data * private)75 static void rawdata_f_data_free(struct rawdata_f_data *private)
76 {
77 if (!private)
78 return;
79
80 aa_put_loaddata(private->loaddata);
81 kvfree(private);
82 }
83
rawdata_f_data_alloc(size_t size)84 static struct rawdata_f_data *rawdata_f_data_alloc(size_t size)
85 {
86 struct rawdata_f_data *ret;
87
88 if (size > SIZE_MAX - sizeof(*ret))
89 return ERR_PTR(-EINVAL);
90
91 ret = kvzalloc(sizeof(*ret) + size, GFP_KERNEL);
92 if (!ret)
93 return ERR_PTR(-ENOMEM);
94
95 return ret;
96 }
97
98 /**
99 * aa_mangle_name - mangle a profile name to std profile layout form
100 * @name: profile name to mangle (NOT NULL)
101 * @target: buffer to store mangled name, same length as @name (MAYBE NULL)
102 *
103 * Returns: length of mangled name
104 */
mangle_name(const char * name,char * target)105 static int mangle_name(const char *name, char *target)
106 {
107 char *t = target;
108
109 while (*name == '/' || *name == '.')
110 name++;
111
112 if (target) {
113 for (; *name; name++) {
114 if (*name == '/')
115 *(t)++ = '.';
116 else if (isspace(*name))
117 *(t)++ = '_';
118 else if (isalnum(*name) || strchr("._-", *name))
119 *(t)++ = *name;
120 }
121
122 *t = 0;
123 } else {
124 int len = 0;
125 for (; *name; name++) {
126 if (isalnum(*name) || isspace(*name) ||
127 strchr("/._-", *name))
128 len++;
129 }
130
131 return len;
132 }
133
134 return t - target;
135 }
136
137
138 /*
139 * aafs - core fns and data for the policy tree
140 */
141
142 #define AAFS_NAME "apparmorfs"
143 static struct vfsmount *aafs_mnt;
144 static int aafs_count;
145
146
aafs_show_path(struct seq_file * seq,struct dentry * dentry)147 static int aafs_show_path(struct seq_file *seq, struct dentry *dentry)
148 {
149 seq_printf(seq, "%s:[%lu]", AAFS_NAME, d_inode(dentry)->i_ino);
150 return 0;
151 }
152
aafs_free_inode(struct inode * inode)153 static void aafs_free_inode(struct inode *inode)
154 {
155 if (S_ISLNK(inode->i_mode))
156 kfree(inode->i_link);
157 free_inode_nonrcu(inode);
158 }
159
160 static const struct super_operations aafs_super_ops = {
161 .statfs = simple_statfs,
162 .free_inode = aafs_free_inode,
163 .show_path = aafs_show_path,
164 };
165
apparmorfs_fill_super(struct super_block * sb,struct fs_context * fc)166 static int apparmorfs_fill_super(struct super_block *sb, struct fs_context *fc)
167 {
168 static struct tree_descr files[] = { {""} };
169 int error;
170
171 error = simple_fill_super(sb, AAFS_MAGIC, files);
172 if (error)
173 return error;
174 sb->s_op = &aafs_super_ops;
175
176 return 0;
177 }
178
apparmorfs_get_tree(struct fs_context * fc)179 static int apparmorfs_get_tree(struct fs_context *fc)
180 {
181 return get_tree_single(fc, apparmorfs_fill_super);
182 }
183
184 static const struct fs_context_operations apparmorfs_context_ops = {
185 .get_tree = apparmorfs_get_tree,
186 };
187
apparmorfs_init_fs_context(struct fs_context * fc)188 static int apparmorfs_init_fs_context(struct fs_context *fc)
189 {
190 fc->ops = &apparmorfs_context_ops;
191 return 0;
192 }
193
194 static struct file_system_type aafs_ops = {
195 .owner = THIS_MODULE,
196 .name = AAFS_NAME,
197 .init_fs_context = apparmorfs_init_fs_context,
198 .kill_sb = kill_anon_super,
199 };
200
201 /**
202 * __aafs_setup_d_inode - basic inode setup for apparmorfs
203 * @dir: parent directory for the dentry
204 * @dentry: dentry we are seting the inode up for
205 * @mode: permissions the file should have
206 * @data: data to store on inode.i_private, available in open()
207 * @link: if symlink, symlink target string
208 * @fops: struct file_operations that should be used
209 * @iops: struct of inode_operations that should be used
210 */
__aafs_setup_d_inode(struct inode * dir,struct dentry * dentry,umode_t mode,void * data,char * link,const struct file_operations * fops,const struct inode_operations * iops)211 static int __aafs_setup_d_inode(struct inode *dir, struct dentry *dentry,
212 umode_t mode, void *data, char *link,
213 const struct file_operations *fops,
214 const struct inode_operations *iops)
215 {
216 struct inode *inode = new_inode(dir->i_sb);
217
218 AA_BUG(!dir);
219 AA_BUG(!dentry);
220
221 if (!inode)
222 return -ENOMEM;
223
224 inode->i_ino = get_next_ino();
225 inode->i_mode = mode;
226 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
227 inode->i_private = data;
228 if (S_ISDIR(mode)) {
229 inode->i_op = iops ? iops : &simple_dir_inode_operations;
230 inode->i_fop = &simple_dir_operations;
231 inc_nlink(inode);
232 inc_nlink(dir);
233 } else if (S_ISLNK(mode)) {
234 inode->i_op = iops ? iops : &simple_symlink_inode_operations;
235 inode->i_link = link;
236 } else {
237 inode->i_fop = fops;
238 }
239 d_instantiate(dentry, inode);
240 dget(dentry);
241
242 return 0;
243 }
244
245 /**
246 * aafs_create - create a dentry in the apparmorfs filesystem
247 *
248 * @name: name of dentry to create
249 * @mode: permissions the file should have
250 * @parent: parent directory for this dentry
251 * @data: data to store on inode.i_private, available in open()
252 * @link: if symlink, symlink target string
253 * @fops: struct file_operations that should be used for
254 * @iops: struct of inode_operations that should be used
255 *
256 * This is the basic "create a xxx" function for apparmorfs.
257 *
258 * Returns a pointer to a dentry if it succeeds, that must be free with
259 * aafs_remove(). Will return ERR_PTR on failure.
260 */
aafs_create(const char * name,umode_t mode,struct dentry * parent,void * data,void * link,const struct file_operations * fops,const struct inode_operations * iops)261 static struct dentry *aafs_create(const char *name, umode_t mode,
262 struct dentry *parent, void *data, void *link,
263 const struct file_operations *fops,
264 const struct inode_operations *iops)
265 {
266 struct dentry *dentry;
267 struct inode *dir;
268 int error;
269
270 AA_BUG(!name);
271 AA_BUG(!parent);
272
273 if (!(mode & S_IFMT))
274 mode = (mode & S_IALLUGO) | S_IFREG;
275
276 error = simple_pin_fs(&aafs_ops, &aafs_mnt, &aafs_count);
277 if (error)
278 return ERR_PTR(error);
279
280 dir = d_inode(parent);
281
282 inode_lock(dir);
283 dentry = lookup_one_len(name, parent, strlen(name));
284 if (IS_ERR(dentry)) {
285 error = PTR_ERR(dentry);
286 goto fail_lock;
287 }
288
289 if (d_really_is_positive(dentry)) {
290 error = -EEXIST;
291 goto fail_dentry;
292 }
293
294 error = __aafs_setup_d_inode(dir, dentry, mode, data, link, fops, iops);
295 if (error)
296 goto fail_dentry;
297 inode_unlock(dir);
298
299 return dentry;
300
301 fail_dentry:
302 dput(dentry);
303
304 fail_lock:
305 inode_unlock(dir);
306 simple_release_fs(&aafs_mnt, &aafs_count);
307
308 return ERR_PTR(error);
309 }
310
311 /**
312 * aafs_create_file - create a file in the apparmorfs filesystem
313 *
314 * @name: name of dentry to create
315 * @mode: permissions the file should have
316 * @parent: parent directory for this dentry
317 * @data: data to store on inode.i_private, available in open()
318 * @fops: struct file_operations that should be used for
319 *
320 * see aafs_create
321 */
aafs_create_file(const char * name,umode_t mode,struct dentry * parent,void * data,const struct file_operations * fops)322 static struct dentry *aafs_create_file(const char *name, umode_t mode,
323 struct dentry *parent, void *data,
324 const struct file_operations *fops)
325 {
326 return aafs_create(name, mode, parent, data, NULL, fops, NULL);
327 }
328
329 /**
330 * aafs_create_dir - create a directory in the apparmorfs filesystem
331 *
332 * @name: name of dentry to create
333 * @parent: parent directory for this dentry
334 *
335 * see aafs_create
336 */
aafs_create_dir(const char * name,struct dentry * parent)337 static struct dentry *aafs_create_dir(const char *name, struct dentry *parent)
338 {
339 return aafs_create(name, S_IFDIR | 0755, parent, NULL, NULL, NULL,
340 NULL);
341 }
342
343 /**
344 * aafs_remove - removes a file or directory from the apparmorfs filesystem
345 *
346 * @dentry: dentry of the file/directory/symlink to removed.
347 */
aafs_remove(struct dentry * dentry)348 static void aafs_remove(struct dentry *dentry)
349 {
350 struct inode *dir;
351
352 if (!dentry || IS_ERR(dentry))
353 return;
354
355 dir = d_inode(dentry->d_parent);
356 inode_lock(dir);
357 if (simple_positive(dentry)) {
358 if (d_is_dir(dentry))
359 simple_rmdir(dir, dentry);
360 else
361 simple_unlink(dir, dentry);
362 d_delete(dentry);
363 dput(dentry);
364 }
365 inode_unlock(dir);
366 simple_release_fs(&aafs_mnt, &aafs_count);
367 }
368
369
370 /*
371 * aa_fs - policy load/replace/remove
372 */
373
374 /**
375 * aa_simple_write_to_buffer - common routine for getting policy from user
376 * @userbuf: user buffer to copy data from (NOT NULL)
377 * @alloc_size: size of user buffer (REQUIRES: @alloc_size >= @copy_size)
378 * @copy_size: size of data to copy from user buffer
379 * @pos: position write is at in the file (NOT NULL)
380 *
381 * Returns: kernel buffer containing copy of user buffer data or an
382 * ERR_PTR on failure.
383 */
aa_simple_write_to_buffer(const char __user * userbuf,size_t alloc_size,size_t copy_size,loff_t * pos)384 static struct aa_loaddata *aa_simple_write_to_buffer(const char __user *userbuf,
385 size_t alloc_size,
386 size_t copy_size,
387 loff_t *pos)
388 {
389 struct aa_loaddata *data;
390
391 AA_BUG(copy_size > alloc_size);
392
393 if (*pos != 0)
394 /* only writes from pos 0, that is complete writes */
395 return ERR_PTR(-ESPIPE);
396
397 /* freed by caller to simple_write_to_buffer */
398 data = aa_loaddata_alloc(alloc_size);
399 if (IS_ERR(data))
400 return data;
401
402 data->size = copy_size;
403 if (copy_from_user(data->data, userbuf, copy_size)) {
404 kvfree(data);
405 return ERR_PTR(-EFAULT);
406 }
407
408 return data;
409 }
410
policy_update(u32 mask,const char __user * buf,size_t size,loff_t * pos,struct aa_ns * ns)411 static ssize_t policy_update(u32 mask, const char __user *buf, size_t size,
412 loff_t *pos, struct aa_ns *ns)
413 {
414 struct aa_loaddata *data;
415 struct aa_label *label;
416 ssize_t error;
417
418 label = begin_current_label_crit_section();
419
420 /* high level check about policy management - fine grained in
421 * below after unpack
422 */
423 error = aa_may_manage_policy(label, ns, mask);
424 if (error)
425 goto end_section;
426
427 data = aa_simple_write_to_buffer(buf, size, size, pos);
428 error = PTR_ERR(data);
429 if (!IS_ERR(data)) {
430 error = aa_replace_profiles(ns, label, mask, data);
431 aa_put_loaddata(data);
432 }
433 end_section:
434 end_current_label_crit_section(label);
435
436 return error;
437 }
438
439 /* .load file hook fn to load policy */
profile_load(struct file * f,const char __user * buf,size_t size,loff_t * pos)440 static ssize_t profile_load(struct file *f, const char __user *buf, size_t size,
441 loff_t *pos)
442 {
443 struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
444 int error = policy_update(AA_MAY_LOAD_POLICY, buf, size, pos, ns);
445
446 aa_put_ns(ns);
447
448 return error;
449 }
450
451 static const struct file_operations aa_fs_profile_load = {
452 .write = profile_load,
453 .llseek = default_llseek,
454 };
455
456 /* .replace file hook fn to load and/or replace policy */
profile_replace(struct file * f,const char __user * buf,size_t size,loff_t * pos)457 static ssize_t profile_replace(struct file *f, const char __user *buf,
458 size_t size, loff_t *pos)
459 {
460 struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
461 int error = policy_update(AA_MAY_LOAD_POLICY | AA_MAY_REPLACE_POLICY,
462 buf, size, pos, ns);
463 aa_put_ns(ns);
464
465 return error;
466 }
467
468 static const struct file_operations aa_fs_profile_replace = {
469 .write = profile_replace,
470 .llseek = default_llseek,
471 };
472
473 /* .remove file hook fn to remove loaded policy */
profile_remove(struct file * f,const char __user * buf,size_t size,loff_t * pos)474 static ssize_t profile_remove(struct file *f, const char __user *buf,
475 size_t size, loff_t *pos)
476 {
477 struct aa_loaddata *data;
478 struct aa_label *label;
479 ssize_t error;
480 struct aa_ns *ns = aa_get_ns(f->f_inode->i_private);
481
482 label = begin_current_label_crit_section();
483 /* high level check about policy management - fine grained in
484 * below after unpack
485 */
486 error = aa_may_manage_policy(label, ns, AA_MAY_REMOVE_POLICY);
487 if (error)
488 goto out;
489
490 /*
491 * aa_remove_profile needs a null terminated string so 1 extra
492 * byte is allocated and the copied data is null terminated.
493 */
494 data = aa_simple_write_to_buffer(buf, size + 1, size, pos);
495
496 error = PTR_ERR(data);
497 if (!IS_ERR(data)) {
498 data->data[size] = 0;
499 error = aa_remove_profiles(ns, label, data->data, size);
500 aa_put_loaddata(data);
501 }
502 out:
503 end_current_label_crit_section(label);
504 aa_put_ns(ns);
505 return error;
506 }
507
508 static const struct file_operations aa_fs_profile_remove = {
509 .write = profile_remove,
510 .llseek = default_llseek,
511 };
512
513 struct aa_revision {
514 struct aa_ns *ns;
515 long last_read;
516 };
517
518 /* revision file hook fn for policy loads */
ns_revision_release(struct inode * inode,struct file * file)519 static int ns_revision_release(struct inode *inode, struct file *file)
520 {
521 struct aa_revision *rev = file->private_data;
522
523 if (rev) {
524 aa_put_ns(rev->ns);
525 kfree(rev);
526 }
527
528 return 0;
529 }
530
ns_revision_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)531 static ssize_t ns_revision_read(struct file *file, char __user *buf,
532 size_t size, loff_t *ppos)
533 {
534 struct aa_revision *rev = file->private_data;
535 char buffer[32];
536 long last_read;
537 int avail;
538
539 mutex_lock_nested(&rev->ns->lock, rev->ns->level);
540 last_read = rev->last_read;
541 if (last_read == rev->ns->revision) {
542 mutex_unlock(&rev->ns->lock);
543 if (file->f_flags & O_NONBLOCK)
544 return -EAGAIN;
545 if (wait_event_interruptible(rev->ns->wait,
546 last_read !=
547 READ_ONCE(rev->ns->revision)))
548 return -ERESTARTSYS;
549 mutex_lock_nested(&rev->ns->lock, rev->ns->level);
550 }
551
552 avail = sprintf(buffer, "%ld\n", rev->ns->revision);
553 if (*ppos + size > avail) {
554 rev->last_read = rev->ns->revision;
555 *ppos = 0;
556 }
557 mutex_unlock(&rev->ns->lock);
558
559 return simple_read_from_buffer(buf, size, ppos, buffer, avail);
560 }
561
ns_revision_open(struct inode * inode,struct file * file)562 static int ns_revision_open(struct inode *inode, struct file *file)
563 {
564 struct aa_revision *rev = kzalloc(sizeof(*rev), GFP_KERNEL);
565
566 if (!rev)
567 return -ENOMEM;
568
569 rev->ns = aa_get_ns(inode->i_private);
570 if (!rev->ns)
571 rev->ns = aa_get_current_ns();
572 file->private_data = rev;
573
574 return 0;
575 }
576
ns_revision_poll(struct file * file,poll_table * pt)577 static __poll_t ns_revision_poll(struct file *file, poll_table *pt)
578 {
579 struct aa_revision *rev = file->private_data;
580 __poll_t mask = 0;
581
582 if (rev) {
583 mutex_lock_nested(&rev->ns->lock, rev->ns->level);
584 poll_wait(file, &rev->ns->wait, pt);
585 if (rev->last_read < rev->ns->revision)
586 mask |= EPOLLIN | EPOLLRDNORM;
587 mutex_unlock(&rev->ns->lock);
588 }
589
590 return mask;
591 }
592
__aa_bump_ns_revision(struct aa_ns * ns)593 void __aa_bump_ns_revision(struct aa_ns *ns)
594 {
595 WRITE_ONCE(ns->revision, READ_ONCE(ns->revision) + 1);
596 wake_up_interruptible(&ns->wait);
597 }
598
599 static const struct file_operations aa_fs_ns_revision_fops = {
600 .owner = THIS_MODULE,
601 .open = ns_revision_open,
602 .poll = ns_revision_poll,
603 .read = ns_revision_read,
604 .llseek = generic_file_llseek,
605 .release = ns_revision_release,
606 };
607
profile_query_cb(struct aa_profile * profile,struct aa_perms * perms,const char * match_str,size_t match_len)608 static void profile_query_cb(struct aa_profile *profile, struct aa_perms *perms,
609 const char *match_str, size_t match_len)
610 {
611 struct aa_perms tmp = { };
612 struct aa_dfa *dfa;
613 unsigned int state = 0;
614
615 if (profile_unconfined(profile))
616 return;
617 if (profile->file.dfa && *match_str == AA_CLASS_FILE) {
618 dfa = profile->file.dfa;
619 state = aa_dfa_match_len(dfa, profile->file.start,
620 match_str + 1, match_len - 1);
621 if (state) {
622 struct path_cond cond = { };
623
624 tmp = aa_compute_fperms(dfa, state, &cond);
625 }
626 } else if (profile->policy.dfa) {
627 if (!PROFILE_MEDIATES(profile, *match_str))
628 return; /* no change to current perms */
629 dfa = profile->policy.dfa;
630 state = aa_dfa_match_len(dfa, profile->policy.start[0],
631 match_str, match_len);
632 if (state)
633 aa_compute_perms(dfa, state, &tmp);
634 }
635 aa_apply_modes_to_perms(profile, &tmp);
636 aa_perms_accum_raw(perms, &tmp);
637 }
638
639
640 /**
641 * query_data - queries a policy and writes its data to buf
642 * @buf: the resulting data is stored here (NOT NULL)
643 * @buf_len: size of buf
644 * @query: query string used to retrieve data
645 * @query_len: size of query including second NUL byte
646 *
647 * The buffers pointed to by buf and query may overlap. The query buffer is
648 * parsed before buf is written to.
649 *
650 * The query should look like "<LABEL>\0<KEY>\0", where <LABEL> is the name of
651 * the security confinement context and <KEY> is the name of the data to
652 * retrieve. <LABEL> and <KEY> must not be NUL-terminated.
653 *
654 * Don't expect the contents of buf to be preserved on failure.
655 *
656 * Returns: number of characters written to buf or -errno on failure
657 */
query_data(char * buf,size_t buf_len,char * query,size_t query_len)658 static ssize_t query_data(char *buf, size_t buf_len,
659 char *query, size_t query_len)
660 {
661 char *out;
662 const char *key;
663 struct label_it i;
664 struct aa_label *label, *curr;
665 struct aa_profile *profile;
666 struct aa_data *data;
667 u32 bytes, blocks;
668 __le32 outle32;
669
670 if (!query_len)
671 return -EINVAL; /* need a query */
672
673 key = query + strnlen(query, query_len) + 1;
674 if (key + 1 >= query + query_len)
675 return -EINVAL; /* not enough space for a non-empty key */
676 if (key + strnlen(key, query + query_len - key) >= query + query_len)
677 return -EINVAL; /* must end with NUL */
678
679 if (buf_len < sizeof(bytes) + sizeof(blocks))
680 return -EINVAL; /* not enough space */
681
682 curr = begin_current_label_crit_section();
683 label = aa_label_parse(curr, query, GFP_KERNEL, false, false);
684 end_current_label_crit_section(curr);
685 if (IS_ERR(label))
686 return PTR_ERR(label);
687
688 /* We are going to leave space for two numbers. The first is the total
689 * number of bytes we are writing after the first number. This is so
690 * users can read the full output without reallocation.
691 *
692 * The second number is the number of data blocks we're writing. An
693 * application might be confined by multiple policies having data in
694 * the same key.
695 */
696 memset(buf, 0, sizeof(bytes) + sizeof(blocks));
697 out = buf + sizeof(bytes) + sizeof(blocks);
698
699 blocks = 0;
700 label_for_each_confined(i, label, profile) {
701 if (!profile->data)
702 continue;
703
704 data = rhashtable_lookup_fast(profile->data, &key,
705 profile->data->p);
706
707 if (data) {
708 if (out + sizeof(outle32) + data->size > buf +
709 buf_len) {
710 aa_put_label(label);
711 return -EINVAL; /* not enough space */
712 }
713 outle32 = __cpu_to_le32(data->size);
714 memcpy(out, &outle32, sizeof(outle32));
715 out += sizeof(outle32);
716 memcpy(out, data->data, data->size);
717 out += data->size;
718 blocks++;
719 }
720 }
721 aa_put_label(label);
722
723 outle32 = __cpu_to_le32(out - buf - sizeof(bytes));
724 memcpy(buf, &outle32, sizeof(outle32));
725 outle32 = __cpu_to_le32(blocks);
726 memcpy(buf + sizeof(bytes), &outle32, sizeof(outle32));
727
728 return out - buf;
729 }
730
731 /**
732 * query_label - queries a label and writes permissions to buf
733 * @buf: the resulting permissions string is stored here (NOT NULL)
734 * @buf_len: size of buf
735 * @query: binary query string to match against the dfa
736 * @query_len: size of query
737 * @view_only: only compute for querier's view
738 *
739 * The buffers pointed to by buf and query may overlap. The query buffer is
740 * parsed before buf is written to.
741 *
742 * The query should look like "LABEL_NAME\0DFA_STRING" where LABEL_NAME is
743 * the name of the label, in the current namespace, that is to be queried and
744 * DFA_STRING is a binary string to match against the label(s)'s DFA.
745 *
746 * LABEL_NAME must be NUL terminated. DFA_STRING may contain NUL characters
747 * but must *not* be NUL terminated.
748 *
749 * Returns: number of characters written to buf or -errno on failure
750 */
query_label(char * buf,size_t buf_len,char * query,size_t query_len,bool view_only)751 static ssize_t query_label(char *buf, size_t buf_len,
752 char *query, size_t query_len, bool view_only)
753 {
754 struct aa_profile *profile;
755 struct aa_label *label, *curr;
756 char *label_name, *match_str;
757 size_t label_name_len, match_len;
758 struct aa_perms perms;
759 struct label_it i;
760
761 if (!query_len)
762 return -EINVAL;
763
764 label_name = query;
765 label_name_len = strnlen(query, query_len);
766 if (!label_name_len || label_name_len == query_len)
767 return -EINVAL;
768
769 /**
770 * The extra byte is to account for the null byte between the
771 * profile name and dfa string. profile_name_len is greater
772 * than zero and less than query_len, so a byte can be safely
773 * added or subtracted.
774 */
775 match_str = label_name + label_name_len + 1;
776 match_len = query_len - label_name_len - 1;
777
778 curr = begin_current_label_crit_section();
779 label = aa_label_parse(curr, label_name, GFP_KERNEL, false, false);
780 end_current_label_crit_section(curr);
781 if (IS_ERR(label))
782 return PTR_ERR(label);
783
784 perms = allperms;
785 if (view_only) {
786 label_for_each_in_ns(i, labels_ns(label), label, profile) {
787 profile_query_cb(profile, &perms, match_str, match_len);
788 }
789 } else {
790 label_for_each(i, label, profile) {
791 profile_query_cb(profile, &perms, match_str, match_len);
792 }
793 }
794 aa_put_label(label);
795
796 return scnprintf(buf, buf_len,
797 "allow 0x%08x\ndeny 0x%08x\naudit 0x%08x\nquiet 0x%08x\n",
798 perms.allow, perms.deny, perms.audit, perms.quiet);
799 }
800
801 /*
802 * Transaction based IO.
803 * The file expects a write which triggers the transaction, and then
804 * possibly a read(s) which collects the result - which is stored in a
805 * file-local buffer. Once a new write is performed, a new set of results
806 * are stored in the file-local buffer.
807 */
808 struct multi_transaction {
809 struct kref count;
810 ssize_t size;
811 char data[];
812 };
813
814 #define MULTI_TRANSACTION_LIMIT (PAGE_SIZE - sizeof(struct multi_transaction))
815 /* TODO: replace with per file lock */
816 static DEFINE_SPINLOCK(multi_transaction_lock);
817
multi_transaction_kref(struct kref * kref)818 static void multi_transaction_kref(struct kref *kref)
819 {
820 struct multi_transaction *t;
821
822 t = container_of(kref, struct multi_transaction, count);
823 free_page((unsigned long) t);
824 }
825
826 static struct multi_transaction *
get_multi_transaction(struct multi_transaction * t)827 get_multi_transaction(struct multi_transaction *t)
828 {
829 if (t)
830 kref_get(&(t->count));
831
832 return t;
833 }
834
put_multi_transaction(struct multi_transaction * t)835 static void put_multi_transaction(struct multi_transaction *t)
836 {
837 if (t)
838 kref_put(&(t->count), multi_transaction_kref);
839 }
840
841 /* does not increment @new's count */
multi_transaction_set(struct file * file,struct multi_transaction * new,size_t n)842 static void multi_transaction_set(struct file *file,
843 struct multi_transaction *new, size_t n)
844 {
845 struct multi_transaction *old;
846
847 AA_BUG(n > MULTI_TRANSACTION_LIMIT);
848
849 new->size = n;
850 spin_lock(&multi_transaction_lock);
851 old = (struct multi_transaction *) file->private_data;
852 file->private_data = new;
853 spin_unlock(&multi_transaction_lock);
854 put_multi_transaction(old);
855 }
856
multi_transaction_new(struct file * file,const char __user * buf,size_t size)857 static struct multi_transaction *multi_transaction_new(struct file *file,
858 const char __user *buf,
859 size_t size)
860 {
861 struct multi_transaction *t;
862
863 if (size > MULTI_TRANSACTION_LIMIT - 1)
864 return ERR_PTR(-EFBIG);
865
866 t = (struct multi_transaction *)get_zeroed_page(GFP_KERNEL);
867 if (!t)
868 return ERR_PTR(-ENOMEM);
869 kref_init(&t->count);
870 if (copy_from_user(t->data, buf, size))
871 return ERR_PTR(-EFAULT);
872
873 return t;
874 }
875
multi_transaction_read(struct file * file,char __user * buf,size_t size,loff_t * pos)876 static ssize_t multi_transaction_read(struct file *file, char __user *buf,
877 size_t size, loff_t *pos)
878 {
879 struct multi_transaction *t;
880 ssize_t ret;
881
882 spin_lock(&multi_transaction_lock);
883 t = get_multi_transaction(file->private_data);
884 spin_unlock(&multi_transaction_lock);
885 if (!t)
886 return 0;
887
888 ret = simple_read_from_buffer(buf, size, pos, t->data, t->size);
889 put_multi_transaction(t);
890
891 return ret;
892 }
893
multi_transaction_release(struct inode * inode,struct file * file)894 static int multi_transaction_release(struct inode *inode, struct file *file)
895 {
896 put_multi_transaction(file->private_data);
897
898 return 0;
899 }
900
901 #define QUERY_CMD_LABEL "label\0"
902 #define QUERY_CMD_LABEL_LEN 6
903 #define QUERY_CMD_PROFILE "profile\0"
904 #define QUERY_CMD_PROFILE_LEN 8
905 #define QUERY_CMD_LABELALL "labelall\0"
906 #define QUERY_CMD_LABELALL_LEN 9
907 #define QUERY_CMD_DATA "data\0"
908 #define QUERY_CMD_DATA_LEN 5
909
910 /**
911 * aa_write_access - generic permissions and data query
912 * @file: pointer to open apparmorfs/access file
913 * @ubuf: user buffer containing the complete query string (NOT NULL)
914 * @count: size of ubuf
915 * @ppos: position in the file (MUST BE ZERO)
916 *
917 * Allows for one permissions or data query per open(), write(), and read()
918 * sequence. The only queries currently supported are label-based queries for
919 * permissions or data.
920 *
921 * For permissions queries, ubuf must begin with "label\0", followed by the
922 * profile query specific format described in the query_label() function
923 * documentation.
924 *
925 * For data queries, ubuf must have the form "data\0<LABEL>\0<KEY>\0", where
926 * <LABEL> is the name of the security confinement context and <KEY> is the
927 * name of the data to retrieve.
928 *
929 * Returns: number of bytes written or -errno on failure
930 */
aa_write_access(struct file * file,const char __user * ubuf,size_t count,loff_t * ppos)931 static ssize_t aa_write_access(struct file *file, const char __user *ubuf,
932 size_t count, loff_t *ppos)
933 {
934 struct multi_transaction *t;
935 ssize_t len;
936
937 if (*ppos)
938 return -ESPIPE;
939
940 t = multi_transaction_new(file, ubuf, count);
941 if (IS_ERR(t))
942 return PTR_ERR(t);
943
944 if (count > QUERY_CMD_PROFILE_LEN &&
945 !memcmp(t->data, QUERY_CMD_PROFILE, QUERY_CMD_PROFILE_LEN)) {
946 len = query_label(t->data, MULTI_TRANSACTION_LIMIT,
947 t->data + QUERY_CMD_PROFILE_LEN,
948 count - QUERY_CMD_PROFILE_LEN, true);
949 } else if (count > QUERY_CMD_LABEL_LEN &&
950 !memcmp(t->data, QUERY_CMD_LABEL, QUERY_CMD_LABEL_LEN)) {
951 len = query_label(t->data, MULTI_TRANSACTION_LIMIT,
952 t->data + QUERY_CMD_LABEL_LEN,
953 count - QUERY_CMD_LABEL_LEN, true);
954 } else if (count > QUERY_CMD_LABELALL_LEN &&
955 !memcmp(t->data, QUERY_CMD_LABELALL,
956 QUERY_CMD_LABELALL_LEN)) {
957 len = query_label(t->data, MULTI_TRANSACTION_LIMIT,
958 t->data + QUERY_CMD_LABELALL_LEN,
959 count - QUERY_CMD_LABELALL_LEN, false);
960 } else if (count > QUERY_CMD_DATA_LEN &&
961 !memcmp(t->data, QUERY_CMD_DATA, QUERY_CMD_DATA_LEN)) {
962 len = query_data(t->data, MULTI_TRANSACTION_LIMIT,
963 t->data + QUERY_CMD_DATA_LEN,
964 count - QUERY_CMD_DATA_LEN);
965 } else
966 len = -EINVAL;
967
968 if (len < 0) {
969 put_multi_transaction(t);
970 return len;
971 }
972
973 multi_transaction_set(file, t, len);
974
975 return count;
976 }
977
978 static const struct file_operations aa_sfs_access = {
979 .write = aa_write_access,
980 .read = multi_transaction_read,
981 .release = multi_transaction_release,
982 .llseek = generic_file_llseek,
983 };
984
aa_sfs_seq_show(struct seq_file * seq,void * v)985 static int aa_sfs_seq_show(struct seq_file *seq, void *v)
986 {
987 struct aa_sfs_entry *fs_file = seq->private;
988
989 if (!fs_file)
990 return 0;
991
992 switch (fs_file->v_type) {
993 case AA_SFS_TYPE_BOOLEAN:
994 seq_printf(seq, "%s\n", fs_file->v.boolean ? "yes" : "no");
995 break;
996 case AA_SFS_TYPE_STRING:
997 seq_printf(seq, "%s\n", fs_file->v.string);
998 break;
999 case AA_SFS_TYPE_U64:
1000 seq_printf(seq, "%#08lx\n", fs_file->v.u64);
1001 break;
1002 default:
1003 /* Ignore unpritable entry types. */
1004 break;
1005 }
1006
1007 return 0;
1008 }
1009
aa_sfs_seq_open(struct inode * inode,struct file * file)1010 static int aa_sfs_seq_open(struct inode *inode, struct file *file)
1011 {
1012 return single_open(file, aa_sfs_seq_show, inode->i_private);
1013 }
1014
1015 const struct file_operations aa_sfs_seq_file_ops = {
1016 .owner = THIS_MODULE,
1017 .open = aa_sfs_seq_open,
1018 .read = seq_read,
1019 .llseek = seq_lseek,
1020 .release = single_release,
1021 };
1022
1023 /*
1024 * profile based file operations
1025 * policy/profiles/XXXX/profiles/ *
1026 */
1027
1028 #define SEQ_PROFILE_FOPS(NAME) \
1029 static int seq_profile_ ##NAME ##_open(struct inode *inode, struct file *file)\
1030 { \
1031 return seq_profile_open(inode, file, seq_profile_ ##NAME ##_show); \
1032 } \
1033 \
1034 static const struct file_operations seq_profile_ ##NAME ##_fops = { \
1035 .owner = THIS_MODULE, \
1036 .open = seq_profile_ ##NAME ##_open, \
1037 .read = seq_read, \
1038 .llseek = seq_lseek, \
1039 .release = seq_profile_release, \
1040 } \
1041
seq_profile_open(struct inode * inode,struct file * file,int (* show)(struct seq_file *,void *))1042 static int seq_profile_open(struct inode *inode, struct file *file,
1043 int (*show)(struct seq_file *, void *))
1044 {
1045 struct aa_proxy *proxy = aa_get_proxy(inode->i_private);
1046 int error = single_open(file, show, proxy);
1047
1048 if (error) {
1049 file->private_data = NULL;
1050 aa_put_proxy(proxy);
1051 }
1052
1053 return error;
1054 }
1055
seq_profile_release(struct inode * inode,struct file * file)1056 static int seq_profile_release(struct inode *inode, struct file *file)
1057 {
1058 struct seq_file *seq = (struct seq_file *) file->private_data;
1059 if (seq)
1060 aa_put_proxy(seq->private);
1061 return single_release(inode, file);
1062 }
1063
seq_profile_name_show(struct seq_file * seq,void * v)1064 static int seq_profile_name_show(struct seq_file *seq, void *v)
1065 {
1066 struct aa_proxy *proxy = seq->private;
1067 struct aa_label *label = aa_get_label_rcu(&proxy->label);
1068 struct aa_profile *profile = labels_profile(label);
1069 seq_printf(seq, "%s\n", profile->base.name);
1070 aa_put_label(label);
1071
1072 return 0;
1073 }
1074
seq_profile_mode_show(struct seq_file * seq,void * v)1075 static int seq_profile_mode_show(struct seq_file *seq, void *v)
1076 {
1077 struct aa_proxy *proxy = seq->private;
1078 struct aa_label *label = aa_get_label_rcu(&proxy->label);
1079 struct aa_profile *profile = labels_profile(label);
1080 seq_printf(seq, "%s\n", aa_profile_mode_names[profile->mode]);
1081 aa_put_label(label);
1082
1083 return 0;
1084 }
1085
seq_profile_attach_show(struct seq_file * seq,void * v)1086 static int seq_profile_attach_show(struct seq_file *seq, void *v)
1087 {
1088 struct aa_proxy *proxy = seq->private;
1089 struct aa_label *label = aa_get_label_rcu(&proxy->label);
1090 struct aa_profile *profile = labels_profile(label);
1091 if (profile->attach)
1092 seq_printf(seq, "%s\n", profile->attach);
1093 else if (profile->xmatch)
1094 seq_puts(seq, "<unknown>\n");
1095 else
1096 seq_printf(seq, "%s\n", profile->base.name);
1097 aa_put_label(label);
1098
1099 return 0;
1100 }
1101
seq_profile_hash_show(struct seq_file * seq,void * v)1102 static int seq_profile_hash_show(struct seq_file *seq, void *v)
1103 {
1104 struct aa_proxy *proxy = seq->private;
1105 struct aa_label *label = aa_get_label_rcu(&proxy->label);
1106 struct aa_profile *profile = labels_profile(label);
1107 unsigned int i, size = aa_hash_size();
1108
1109 if (profile->hash) {
1110 for (i = 0; i < size; i++)
1111 seq_printf(seq, "%.2x", profile->hash[i]);
1112 seq_putc(seq, '\n');
1113 }
1114 aa_put_label(label);
1115
1116 return 0;
1117 }
1118
1119 SEQ_PROFILE_FOPS(name);
1120 SEQ_PROFILE_FOPS(mode);
1121 SEQ_PROFILE_FOPS(attach);
1122 SEQ_PROFILE_FOPS(hash);
1123
1124 /*
1125 * namespace based files
1126 * several root files and
1127 * policy/ *
1128 */
1129
1130 #define SEQ_NS_FOPS(NAME) \
1131 static int seq_ns_ ##NAME ##_open(struct inode *inode, struct file *file) \
1132 { \
1133 return single_open(file, seq_ns_ ##NAME ##_show, inode->i_private); \
1134 } \
1135 \
1136 static const struct file_operations seq_ns_ ##NAME ##_fops = { \
1137 .owner = THIS_MODULE, \
1138 .open = seq_ns_ ##NAME ##_open, \
1139 .read = seq_read, \
1140 .llseek = seq_lseek, \
1141 .release = single_release, \
1142 } \
1143
seq_ns_stacked_show(struct seq_file * seq,void * v)1144 static int seq_ns_stacked_show(struct seq_file *seq, void *v)
1145 {
1146 struct aa_label *label;
1147
1148 label = begin_current_label_crit_section();
1149 seq_printf(seq, "%s\n", label->size > 1 ? "yes" : "no");
1150 end_current_label_crit_section(label);
1151
1152 return 0;
1153 }
1154
seq_ns_nsstacked_show(struct seq_file * seq,void * v)1155 static int seq_ns_nsstacked_show(struct seq_file *seq, void *v)
1156 {
1157 struct aa_label *label;
1158 struct aa_profile *profile;
1159 struct label_it it;
1160 int count = 1;
1161
1162 label = begin_current_label_crit_section();
1163
1164 if (label->size > 1) {
1165 label_for_each(it, label, profile)
1166 if (profile->ns != labels_ns(label)) {
1167 count++;
1168 break;
1169 }
1170 }
1171
1172 seq_printf(seq, "%s\n", count > 1 ? "yes" : "no");
1173 end_current_label_crit_section(label);
1174
1175 return 0;
1176 }
1177
seq_ns_level_show(struct seq_file * seq,void * v)1178 static int seq_ns_level_show(struct seq_file *seq, void *v)
1179 {
1180 struct aa_label *label;
1181
1182 label = begin_current_label_crit_section();
1183 seq_printf(seq, "%d\n", labels_ns(label)->level);
1184 end_current_label_crit_section(label);
1185
1186 return 0;
1187 }
1188
seq_ns_name_show(struct seq_file * seq,void * v)1189 static int seq_ns_name_show(struct seq_file *seq, void *v)
1190 {
1191 struct aa_label *label = begin_current_label_crit_section();
1192 seq_printf(seq, "%s\n", labels_ns(label)->base.name);
1193 end_current_label_crit_section(label);
1194
1195 return 0;
1196 }
1197
1198 SEQ_NS_FOPS(stacked);
1199 SEQ_NS_FOPS(nsstacked);
1200 SEQ_NS_FOPS(level);
1201 SEQ_NS_FOPS(name);
1202
1203
1204 /* policy/raw_data/ * file ops */
1205
1206 #define SEQ_RAWDATA_FOPS(NAME) \
1207 static int seq_rawdata_ ##NAME ##_open(struct inode *inode, struct file *file)\
1208 { \
1209 return seq_rawdata_open(inode, file, seq_rawdata_ ##NAME ##_show); \
1210 } \
1211 \
1212 static const struct file_operations seq_rawdata_ ##NAME ##_fops = { \
1213 .owner = THIS_MODULE, \
1214 .open = seq_rawdata_ ##NAME ##_open, \
1215 .read = seq_read, \
1216 .llseek = seq_lseek, \
1217 .release = seq_rawdata_release, \
1218 } \
1219
seq_rawdata_open(struct inode * inode,struct file * file,int (* show)(struct seq_file *,void *))1220 static int seq_rawdata_open(struct inode *inode, struct file *file,
1221 int (*show)(struct seq_file *, void *))
1222 {
1223 struct aa_loaddata *data = __aa_get_loaddata(inode->i_private);
1224 int error;
1225
1226 if (!data)
1227 /* lost race this ent is being reaped */
1228 return -ENOENT;
1229
1230 error = single_open(file, show, data);
1231 if (error) {
1232 AA_BUG(file->private_data &&
1233 ((struct seq_file *)file->private_data)->private);
1234 aa_put_loaddata(data);
1235 }
1236
1237 return error;
1238 }
1239
seq_rawdata_release(struct inode * inode,struct file * file)1240 static int seq_rawdata_release(struct inode *inode, struct file *file)
1241 {
1242 struct seq_file *seq = (struct seq_file *) file->private_data;
1243
1244 if (seq)
1245 aa_put_loaddata(seq->private);
1246
1247 return single_release(inode, file);
1248 }
1249
seq_rawdata_abi_show(struct seq_file * seq,void * v)1250 static int seq_rawdata_abi_show(struct seq_file *seq, void *v)
1251 {
1252 struct aa_loaddata *data = seq->private;
1253
1254 seq_printf(seq, "v%d\n", data->abi);
1255
1256 return 0;
1257 }
1258
seq_rawdata_revision_show(struct seq_file * seq,void * v)1259 static int seq_rawdata_revision_show(struct seq_file *seq, void *v)
1260 {
1261 struct aa_loaddata *data = seq->private;
1262
1263 seq_printf(seq, "%ld\n", data->revision);
1264
1265 return 0;
1266 }
1267
seq_rawdata_hash_show(struct seq_file * seq,void * v)1268 static int seq_rawdata_hash_show(struct seq_file *seq, void *v)
1269 {
1270 struct aa_loaddata *data = seq->private;
1271 unsigned int i, size = aa_hash_size();
1272
1273 if (data->hash) {
1274 for (i = 0; i < size; i++)
1275 seq_printf(seq, "%.2x", data->hash[i]);
1276 seq_putc(seq, '\n');
1277 }
1278
1279 return 0;
1280 }
1281
seq_rawdata_compressed_size_show(struct seq_file * seq,void * v)1282 static int seq_rawdata_compressed_size_show(struct seq_file *seq, void *v)
1283 {
1284 struct aa_loaddata *data = seq->private;
1285
1286 seq_printf(seq, "%zu\n", data->compressed_size);
1287
1288 return 0;
1289 }
1290
1291 SEQ_RAWDATA_FOPS(abi);
1292 SEQ_RAWDATA_FOPS(revision);
1293 SEQ_RAWDATA_FOPS(hash);
1294 SEQ_RAWDATA_FOPS(compressed_size);
1295
deflate_decompress(char * src,size_t slen,char * dst,size_t dlen)1296 static int deflate_decompress(char *src, size_t slen, char *dst, size_t dlen)
1297 {
1298 int error;
1299 struct z_stream_s strm;
1300
1301 if (aa_g_rawdata_compression_level == 0) {
1302 if (dlen < slen)
1303 return -EINVAL;
1304 memcpy(dst, src, slen);
1305 return 0;
1306 }
1307
1308 memset(&strm, 0, sizeof(strm));
1309
1310 strm.workspace = kvzalloc(zlib_inflate_workspacesize(), GFP_KERNEL);
1311 if (!strm.workspace)
1312 return -ENOMEM;
1313
1314 strm.next_in = src;
1315 strm.avail_in = slen;
1316
1317 error = zlib_inflateInit(&strm);
1318 if (error != Z_OK) {
1319 error = -ENOMEM;
1320 goto fail_inflate_init;
1321 }
1322
1323 strm.next_out = dst;
1324 strm.avail_out = dlen;
1325
1326 error = zlib_inflate(&strm, Z_FINISH);
1327 if (error != Z_STREAM_END)
1328 error = -EINVAL;
1329 else
1330 error = 0;
1331
1332 zlib_inflateEnd(&strm);
1333 fail_inflate_init:
1334 kvfree(strm.workspace);
1335 return error;
1336 }
1337
rawdata_read(struct file * file,char __user * buf,size_t size,loff_t * ppos)1338 static ssize_t rawdata_read(struct file *file, char __user *buf, size_t size,
1339 loff_t *ppos)
1340 {
1341 struct rawdata_f_data *private = file->private_data;
1342
1343 return simple_read_from_buffer(buf, size, ppos,
1344 RAWDATA_F_DATA_BUF(private),
1345 private->loaddata->size);
1346 }
1347
rawdata_release(struct inode * inode,struct file * file)1348 static int rawdata_release(struct inode *inode, struct file *file)
1349 {
1350 rawdata_f_data_free(file->private_data);
1351
1352 return 0;
1353 }
1354
rawdata_open(struct inode * inode,struct file * file)1355 static int rawdata_open(struct inode *inode, struct file *file)
1356 {
1357 int error;
1358 struct aa_loaddata *loaddata;
1359 struct rawdata_f_data *private;
1360
1361 if (!policy_view_capable(NULL))
1362 return -EACCES;
1363
1364 loaddata = __aa_get_loaddata(inode->i_private);
1365 if (!loaddata)
1366 /* lost race: this entry is being reaped */
1367 return -ENOENT;
1368
1369 private = rawdata_f_data_alloc(loaddata->size);
1370 if (IS_ERR(private)) {
1371 error = PTR_ERR(private);
1372 goto fail_private_alloc;
1373 }
1374
1375 private->loaddata = loaddata;
1376
1377 error = deflate_decompress(loaddata->data, loaddata->compressed_size,
1378 RAWDATA_F_DATA_BUF(private),
1379 loaddata->size);
1380 if (error)
1381 goto fail_decompress;
1382
1383 file->private_data = private;
1384 return 0;
1385
1386 fail_decompress:
1387 rawdata_f_data_free(private);
1388 return error;
1389
1390 fail_private_alloc:
1391 aa_put_loaddata(loaddata);
1392 return error;
1393 }
1394
1395 static const struct file_operations rawdata_fops = {
1396 .open = rawdata_open,
1397 .read = rawdata_read,
1398 .llseek = generic_file_llseek,
1399 .release = rawdata_release,
1400 };
1401
remove_rawdata_dents(struct aa_loaddata * rawdata)1402 static void remove_rawdata_dents(struct aa_loaddata *rawdata)
1403 {
1404 int i;
1405
1406 for (i = 0; i < AAFS_LOADDATA_NDENTS; i++) {
1407 if (!IS_ERR_OR_NULL(rawdata->dents[i])) {
1408 /* no refcounts on i_private */
1409 aafs_remove(rawdata->dents[i]);
1410 rawdata->dents[i] = NULL;
1411 }
1412 }
1413 }
1414
__aa_fs_remove_rawdata(struct aa_loaddata * rawdata)1415 void __aa_fs_remove_rawdata(struct aa_loaddata *rawdata)
1416 {
1417 AA_BUG(rawdata->ns && !mutex_is_locked(&rawdata->ns->lock));
1418
1419 if (rawdata->ns) {
1420 remove_rawdata_dents(rawdata);
1421 list_del_init(&rawdata->list);
1422 aa_put_ns(rawdata->ns);
1423 rawdata->ns = NULL;
1424 }
1425 }
1426
__aa_fs_create_rawdata(struct aa_ns * ns,struct aa_loaddata * rawdata)1427 int __aa_fs_create_rawdata(struct aa_ns *ns, struct aa_loaddata *rawdata)
1428 {
1429 struct dentry *dent, *dir;
1430
1431 AA_BUG(!ns);
1432 AA_BUG(!rawdata);
1433 AA_BUG(!mutex_is_locked(&ns->lock));
1434 AA_BUG(!ns_subdata_dir(ns));
1435
1436 /*
1437 * just use ns revision dir was originally created at. This is
1438 * under ns->lock and if load is successful revision will be
1439 * bumped and is guaranteed to be unique
1440 */
1441 rawdata->name = kasprintf(GFP_KERNEL, "%ld", ns->revision);
1442 if (!rawdata->name)
1443 return -ENOMEM;
1444
1445 dir = aafs_create_dir(rawdata->name, ns_subdata_dir(ns));
1446 if (IS_ERR(dir))
1447 /* ->name freed when rawdata freed */
1448 return PTR_ERR(dir);
1449 rawdata->dents[AAFS_LOADDATA_DIR] = dir;
1450
1451 dent = aafs_create_file("abi", S_IFREG | 0444, dir, rawdata,
1452 &seq_rawdata_abi_fops);
1453 if (IS_ERR(dent))
1454 goto fail;
1455 rawdata->dents[AAFS_LOADDATA_ABI] = dent;
1456
1457 dent = aafs_create_file("revision", S_IFREG | 0444, dir, rawdata,
1458 &seq_rawdata_revision_fops);
1459 if (IS_ERR(dent))
1460 goto fail;
1461 rawdata->dents[AAFS_LOADDATA_REVISION] = dent;
1462
1463 if (aa_g_hash_policy) {
1464 dent = aafs_create_file("sha1", S_IFREG | 0444, dir,
1465 rawdata, &seq_rawdata_hash_fops);
1466 if (IS_ERR(dent))
1467 goto fail;
1468 rawdata->dents[AAFS_LOADDATA_HASH] = dent;
1469 }
1470
1471 dent = aafs_create_file("compressed_size", S_IFREG | 0444, dir,
1472 rawdata,
1473 &seq_rawdata_compressed_size_fops);
1474 if (IS_ERR(dent))
1475 goto fail;
1476 rawdata->dents[AAFS_LOADDATA_COMPRESSED_SIZE] = dent;
1477
1478 dent = aafs_create_file("raw_data", S_IFREG | 0444,
1479 dir, rawdata, &rawdata_fops);
1480 if (IS_ERR(dent))
1481 goto fail;
1482 rawdata->dents[AAFS_LOADDATA_DATA] = dent;
1483 d_inode(dent)->i_size = rawdata->size;
1484
1485 rawdata->ns = aa_get_ns(ns);
1486 list_add(&rawdata->list, &ns->rawdata_list);
1487 /* no refcount on inode rawdata */
1488
1489 return 0;
1490
1491 fail:
1492 remove_rawdata_dents(rawdata);
1493
1494 return PTR_ERR(dent);
1495 }
1496
1497 /** fns to setup dynamic per profile/namespace files **/
1498
1499 /**
1500 *
1501 * Requires: @profile->ns->lock held
1502 */
__aafs_profile_rmdir(struct aa_profile * profile)1503 void __aafs_profile_rmdir(struct aa_profile *profile)
1504 {
1505 struct aa_profile *child;
1506 int i;
1507
1508 if (!profile)
1509 return;
1510
1511 list_for_each_entry(child, &profile->base.profiles, base.list)
1512 __aafs_profile_rmdir(child);
1513
1514 for (i = AAFS_PROF_SIZEOF - 1; i >= 0; --i) {
1515 struct aa_proxy *proxy;
1516 if (!profile->dents[i])
1517 continue;
1518
1519 proxy = d_inode(profile->dents[i])->i_private;
1520 aafs_remove(profile->dents[i]);
1521 aa_put_proxy(proxy);
1522 profile->dents[i] = NULL;
1523 }
1524 }
1525
1526 /**
1527 *
1528 * Requires: @old->ns->lock held
1529 */
__aafs_profile_migrate_dents(struct aa_profile * old,struct aa_profile * new)1530 void __aafs_profile_migrate_dents(struct aa_profile *old,
1531 struct aa_profile *new)
1532 {
1533 int i;
1534
1535 AA_BUG(!old);
1536 AA_BUG(!new);
1537 AA_BUG(!mutex_is_locked(&profiles_ns(old)->lock));
1538
1539 for (i = 0; i < AAFS_PROF_SIZEOF; i++) {
1540 new->dents[i] = old->dents[i];
1541 if (new->dents[i])
1542 new->dents[i]->d_inode->i_mtime = current_time(new->dents[i]->d_inode);
1543 old->dents[i] = NULL;
1544 }
1545 }
1546
create_profile_file(struct dentry * dir,const char * name,struct aa_profile * profile,const struct file_operations * fops)1547 static struct dentry *create_profile_file(struct dentry *dir, const char *name,
1548 struct aa_profile *profile,
1549 const struct file_operations *fops)
1550 {
1551 struct aa_proxy *proxy = aa_get_proxy(profile->label.proxy);
1552 struct dentry *dent;
1553
1554 dent = aafs_create_file(name, S_IFREG | 0444, dir, proxy, fops);
1555 if (IS_ERR(dent))
1556 aa_put_proxy(proxy);
1557
1558 return dent;
1559 }
1560
profile_depth(struct aa_profile * profile)1561 static int profile_depth(struct aa_profile *profile)
1562 {
1563 int depth = 0;
1564
1565 rcu_read_lock();
1566 for (depth = 0; profile; profile = rcu_access_pointer(profile->parent))
1567 depth++;
1568 rcu_read_unlock();
1569
1570 return depth;
1571 }
1572
gen_symlink_name(int depth,const char * dirname,const char * fname)1573 static char *gen_symlink_name(int depth, const char *dirname, const char *fname)
1574 {
1575 char *buffer, *s;
1576 int error;
1577 int size = depth * 6 + strlen(dirname) + strlen(fname) + 11;
1578
1579 s = buffer = kmalloc(size, GFP_KERNEL);
1580 if (!buffer)
1581 return ERR_PTR(-ENOMEM);
1582
1583 for (; depth > 0; depth--) {
1584 strcpy(s, "../../");
1585 s += 6;
1586 size -= 6;
1587 }
1588
1589 error = snprintf(s, size, "raw_data/%s/%s", dirname, fname);
1590 if (error >= size || error < 0) {
1591 kfree(buffer);
1592 return ERR_PTR(-ENAMETOOLONG);
1593 }
1594
1595 return buffer;
1596 }
1597
rawdata_link_cb(void * arg)1598 static void rawdata_link_cb(void *arg)
1599 {
1600 kfree(arg);
1601 }
1602
rawdata_get_link_base(struct dentry * dentry,struct inode * inode,struct delayed_call * done,const char * name)1603 static const char *rawdata_get_link_base(struct dentry *dentry,
1604 struct inode *inode,
1605 struct delayed_call *done,
1606 const char *name)
1607 {
1608 struct aa_proxy *proxy = inode->i_private;
1609 struct aa_label *label;
1610 struct aa_profile *profile;
1611 char *target;
1612 int depth;
1613
1614 if (!dentry)
1615 return ERR_PTR(-ECHILD);
1616
1617 label = aa_get_label_rcu(&proxy->label);
1618 profile = labels_profile(label);
1619 depth = profile_depth(profile);
1620 target = gen_symlink_name(depth, profile->rawdata->name, name);
1621 aa_put_label(label);
1622
1623 if (IS_ERR(target))
1624 return target;
1625
1626 set_delayed_call(done, rawdata_link_cb, target);
1627
1628 return target;
1629 }
1630
rawdata_get_link_sha1(struct dentry * dentry,struct inode * inode,struct delayed_call * done)1631 static const char *rawdata_get_link_sha1(struct dentry *dentry,
1632 struct inode *inode,
1633 struct delayed_call *done)
1634 {
1635 return rawdata_get_link_base(dentry, inode, done, "sha1");
1636 }
1637
rawdata_get_link_abi(struct dentry * dentry,struct inode * inode,struct delayed_call * done)1638 static const char *rawdata_get_link_abi(struct dentry *dentry,
1639 struct inode *inode,
1640 struct delayed_call *done)
1641 {
1642 return rawdata_get_link_base(dentry, inode, done, "abi");
1643 }
1644
rawdata_get_link_data(struct dentry * dentry,struct inode * inode,struct delayed_call * done)1645 static const char *rawdata_get_link_data(struct dentry *dentry,
1646 struct inode *inode,
1647 struct delayed_call *done)
1648 {
1649 return rawdata_get_link_base(dentry, inode, done, "raw_data");
1650 }
1651
1652 static const struct inode_operations rawdata_link_sha1_iops = {
1653 .get_link = rawdata_get_link_sha1,
1654 };
1655
1656 static const struct inode_operations rawdata_link_abi_iops = {
1657 .get_link = rawdata_get_link_abi,
1658 };
1659 static const struct inode_operations rawdata_link_data_iops = {
1660 .get_link = rawdata_get_link_data,
1661 };
1662
1663
1664 /*
1665 * Requires: @profile->ns->lock held
1666 */
__aafs_profile_mkdir(struct aa_profile * profile,struct dentry * parent)1667 int __aafs_profile_mkdir(struct aa_profile *profile, struct dentry *parent)
1668 {
1669 struct aa_profile *child;
1670 struct dentry *dent = NULL, *dir;
1671 int error;
1672
1673 AA_BUG(!profile);
1674 AA_BUG(!mutex_is_locked(&profiles_ns(profile)->lock));
1675
1676 if (!parent) {
1677 struct aa_profile *p;
1678 p = aa_deref_parent(profile);
1679 dent = prof_dir(p);
1680 /* adding to parent that previously didn't have children */
1681 dent = aafs_create_dir("profiles", dent);
1682 if (IS_ERR(dent))
1683 goto fail;
1684 prof_child_dir(p) = parent = dent;
1685 }
1686
1687 if (!profile->dirname) {
1688 int len, id_len;
1689 len = mangle_name(profile->base.name, NULL);
1690 id_len = snprintf(NULL, 0, ".%ld", profile->ns->uniq_id);
1691
1692 profile->dirname = kmalloc(len + id_len + 1, GFP_KERNEL);
1693 if (!profile->dirname) {
1694 error = -ENOMEM;
1695 goto fail2;
1696 }
1697
1698 mangle_name(profile->base.name, profile->dirname);
1699 sprintf(profile->dirname + len, ".%ld", profile->ns->uniq_id++);
1700 }
1701
1702 dent = aafs_create_dir(profile->dirname, parent);
1703 if (IS_ERR(dent))
1704 goto fail;
1705 prof_dir(profile) = dir = dent;
1706
1707 dent = create_profile_file(dir, "name", profile,
1708 &seq_profile_name_fops);
1709 if (IS_ERR(dent))
1710 goto fail;
1711 profile->dents[AAFS_PROF_NAME] = dent;
1712
1713 dent = create_profile_file(dir, "mode", profile,
1714 &seq_profile_mode_fops);
1715 if (IS_ERR(dent))
1716 goto fail;
1717 profile->dents[AAFS_PROF_MODE] = dent;
1718
1719 dent = create_profile_file(dir, "attach", profile,
1720 &seq_profile_attach_fops);
1721 if (IS_ERR(dent))
1722 goto fail;
1723 profile->dents[AAFS_PROF_ATTACH] = dent;
1724
1725 if (profile->hash) {
1726 dent = create_profile_file(dir, "sha1", profile,
1727 &seq_profile_hash_fops);
1728 if (IS_ERR(dent))
1729 goto fail;
1730 profile->dents[AAFS_PROF_HASH] = dent;
1731 }
1732
1733 if (profile->rawdata) {
1734 dent = aafs_create("raw_sha1", S_IFLNK | 0444, dir,
1735 profile->label.proxy, NULL, NULL,
1736 &rawdata_link_sha1_iops);
1737 if (IS_ERR(dent))
1738 goto fail;
1739 aa_get_proxy(profile->label.proxy);
1740 profile->dents[AAFS_PROF_RAW_HASH] = dent;
1741
1742 dent = aafs_create("raw_abi", S_IFLNK | 0444, dir,
1743 profile->label.proxy, NULL, NULL,
1744 &rawdata_link_abi_iops);
1745 if (IS_ERR(dent))
1746 goto fail;
1747 aa_get_proxy(profile->label.proxy);
1748 profile->dents[AAFS_PROF_RAW_ABI] = dent;
1749
1750 dent = aafs_create("raw_data", S_IFLNK | 0444, dir,
1751 profile->label.proxy, NULL, NULL,
1752 &rawdata_link_data_iops);
1753 if (IS_ERR(dent))
1754 goto fail;
1755 aa_get_proxy(profile->label.proxy);
1756 profile->dents[AAFS_PROF_RAW_DATA] = dent;
1757 }
1758
1759 list_for_each_entry(child, &profile->base.profiles, base.list) {
1760 error = __aafs_profile_mkdir(child, prof_child_dir(profile));
1761 if (error)
1762 goto fail2;
1763 }
1764
1765 return 0;
1766
1767 fail:
1768 error = PTR_ERR(dent);
1769
1770 fail2:
1771 __aafs_profile_rmdir(profile);
1772
1773 return error;
1774 }
1775
ns_mkdir_op(struct user_namespace * mnt_userns,struct inode * dir,struct dentry * dentry,umode_t mode)1776 static int ns_mkdir_op(struct user_namespace *mnt_userns, struct inode *dir,
1777 struct dentry *dentry, umode_t mode)
1778 {
1779 struct aa_ns *ns, *parent;
1780 /* TODO: improve permission check */
1781 struct aa_label *label;
1782 int error;
1783
1784 label = begin_current_label_crit_section();
1785 error = aa_may_manage_policy(label, NULL, AA_MAY_LOAD_POLICY);
1786 end_current_label_crit_section(label);
1787 if (error)
1788 return error;
1789
1790 parent = aa_get_ns(dir->i_private);
1791 AA_BUG(d_inode(ns_subns_dir(parent)) != dir);
1792
1793 /* we have to unlock and then relock to get locking order right
1794 * for pin_fs
1795 */
1796 inode_unlock(dir);
1797 error = simple_pin_fs(&aafs_ops, &aafs_mnt, &aafs_count);
1798 mutex_lock_nested(&parent->lock, parent->level);
1799 inode_lock_nested(dir, I_MUTEX_PARENT);
1800 if (error)
1801 goto out;
1802
1803 error = __aafs_setup_d_inode(dir, dentry, mode | S_IFDIR, NULL,
1804 NULL, NULL, NULL);
1805 if (error)
1806 goto out_pin;
1807
1808 ns = __aa_find_or_create_ns(parent, READ_ONCE(dentry->d_name.name),
1809 dentry);
1810 if (IS_ERR(ns)) {
1811 error = PTR_ERR(ns);
1812 ns = NULL;
1813 }
1814
1815 aa_put_ns(ns); /* list ref remains */
1816 out_pin:
1817 if (error)
1818 simple_release_fs(&aafs_mnt, &aafs_count);
1819 out:
1820 mutex_unlock(&parent->lock);
1821 aa_put_ns(parent);
1822
1823 return error;
1824 }
1825
ns_rmdir_op(struct inode * dir,struct dentry * dentry)1826 static int ns_rmdir_op(struct inode *dir, struct dentry *dentry)
1827 {
1828 struct aa_ns *ns, *parent;
1829 /* TODO: improve permission check */
1830 struct aa_label *label;
1831 int error;
1832
1833 label = begin_current_label_crit_section();
1834 error = aa_may_manage_policy(label, NULL, AA_MAY_LOAD_POLICY);
1835 end_current_label_crit_section(label);
1836 if (error)
1837 return error;
1838
1839 parent = aa_get_ns(dir->i_private);
1840 /* rmdir calls the generic securityfs functions to remove files
1841 * from the apparmor dir. It is up to the apparmor ns locking
1842 * to avoid races.
1843 */
1844 inode_unlock(dir);
1845 inode_unlock(dentry->d_inode);
1846
1847 mutex_lock_nested(&parent->lock, parent->level);
1848 ns = aa_get_ns(__aa_findn_ns(&parent->sub_ns, dentry->d_name.name,
1849 dentry->d_name.len));
1850 if (!ns) {
1851 error = -ENOENT;
1852 goto out;
1853 }
1854 AA_BUG(ns_dir(ns) != dentry);
1855
1856 __aa_remove_ns(ns);
1857 aa_put_ns(ns);
1858
1859 out:
1860 mutex_unlock(&parent->lock);
1861 inode_lock_nested(dir, I_MUTEX_PARENT);
1862 inode_lock(dentry->d_inode);
1863 aa_put_ns(parent);
1864
1865 return error;
1866 }
1867
1868 static const struct inode_operations ns_dir_inode_operations = {
1869 .lookup = simple_lookup,
1870 .mkdir = ns_mkdir_op,
1871 .rmdir = ns_rmdir_op,
1872 };
1873
__aa_fs_list_remove_rawdata(struct aa_ns * ns)1874 static void __aa_fs_list_remove_rawdata(struct aa_ns *ns)
1875 {
1876 struct aa_loaddata *ent, *tmp;
1877
1878 AA_BUG(!mutex_is_locked(&ns->lock));
1879
1880 list_for_each_entry_safe(ent, tmp, &ns->rawdata_list, list)
1881 __aa_fs_remove_rawdata(ent);
1882 }
1883
1884 /**
1885 *
1886 * Requires: @ns->lock held
1887 */
__aafs_ns_rmdir(struct aa_ns * ns)1888 void __aafs_ns_rmdir(struct aa_ns *ns)
1889 {
1890 struct aa_ns *sub;
1891 struct aa_profile *child;
1892 int i;
1893
1894 if (!ns)
1895 return;
1896 AA_BUG(!mutex_is_locked(&ns->lock));
1897
1898 list_for_each_entry(child, &ns->base.profiles, base.list)
1899 __aafs_profile_rmdir(child);
1900
1901 list_for_each_entry(sub, &ns->sub_ns, base.list) {
1902 mutex_lock_nested(&sub->lock, sub->level);
1903 __aafs_ns_rmdir(sub);
1904 mutex_unlock(&sub->lock);
1905 }
1906
1907 __aa_fs_list_remove_rawdata(ns);
1908
1909 if (ns_subns_dir(ns)) {
1910 sub = d_inode(ns_subns_dir(ns))->i_private;
1911 aa_put_ns(sub);
1912 }
1913 if (ns_subload(ns)) {
1914 sub = d_inode(ns_subload(ns))->i_private;
1915 aa_put_ns(sub);
1916 }
1917 if (ns_subreplace(ns)) {
1918 sub = d_inode(ns_subreplace(ns))->i_private;
1919 aa_put_ns(sub);
1920 }
1921 if (ns_subremove(ns)) {
1922 sub = d_inode(ns_subremove(ns))->i_private;
1923 aa_put_ns(sub);
1924 }
1925 if (ns_subrevision(ns)) {
1926 sub = d_inode(ns_subrevision(ns))->i_private;
1927 aa_put_ns(sub);
1928 }
1929
1930 for (i = AAFS_NS_SIZEOF - 1; i >= 0; --i) {
1931 aafs_remove(ns->dents[i]);
1932 ns->dents[i] = NULL;
1933 }
1934 }
1935
1936 /* assumes cleanup in caller */
__aafs_ns_mkdir_entries(struct aa_ns * ns,struct dentry * dir)1937 static int __aafs_ns_mkdir_entries(struct aa_ns *ns, struct dentry *dir)
1938 {
1939 struct dentry *dent;
1940
1941 AA_BUG(!ns);
1942 AA_BUG(!dir);
1943
1944 dent = aafs_create_dir("profiles", dir);
1945 if (IS_ERR(dent))
1946 return PTR_ERR(dent);
1947 ns_subprofs_dir(ns) = dent;
1948
1949 dent = aafs_create_dir("raw_data", dir);
1950 if (IS_ERR(dent))
1951 return PTR_ERR(dent);
1952 ns_subdata_dir(ns) = dent;
1953
1954 dent = aafs_create_file("revision", 0444, dir, ns,
1955 &aa_fs_ns_revision_fops);
1956 if (IS_ERR(dent))
1957 return PTR_ERR(dent);
1958 aa_get_ns(ns);
1959 ns_subrevision(ns) = dent;
1960
1961 dent = aafs_create_file(".load", 0640, dir, ns,
1962 &aa_fs_profile_load);
1963 if (IS_ERR(dent))
1964 return PTR_ERR(dent);
1965 aa_get_ns(ns);
1966 ns_subload(ns) = dent;
1967
1968 dent = aafs_create_file(".replace", 0640, dir, ns,
1969 &aa_fs_profile_replace);
1970 if (IS_ERR(dent))
1971 return PTR_ERR(dent);
1972 aa_get_ns(ns);
1973 ns_subreplace(ns) = dent;
1974
1975 dent = aafs_create_file(".remove", 0640, dir, ns,
1976 &aa_fs_profile_remove);
1977 if (IS_ERR(dent))
1978 return PTR_ERR(dent);
1979 aa_get_ns(ns);
1980 ns_subremove(ns) = dent;
1981
1982 /* use create_dentry so we can supply private data */
1983 dent = aafs_create("namespaces", S_IFDIR | 0755, dir, ns, NULL, NULL,
1984 &ns_dir_inode_operations);
1985 if (IS_ERR(dent))
1986 return PTR_ERR(dent);
1987 aa_get_ns(ns);
1988 ns_subns_dir(ns) = dent;
1989
1990 return 0;
1991 }
1992
1993 /*
1994 * Requires: @ns->lock held
1995 */
__aafs_ns_mkdir(struct aa_ns * ns,struct dentry * parent,const char * name,struct dentry * dent)1996 int __aafs_ns_mkdir(struct aa_ns *ns, struct dentry *parent, const char *name,
1997 struct dentry *dent)
1998 {
1999 struct aa_ns *sub;
2000 struct aa_profile *child;
2001 struct dentry *dir;
2002 int error;
2003
2004 AA_BUG(!ns);
2005 AA_BUG(!parent);
2006 AA_BUG(!mutex_is_locked(&ns->lock));
2007
2008 if (!name)
2009 name = ns->base.name;
2010
2011 if (!dent) {
2012 /* create ns dir if it doesn't already exist */
2013 dent = aafs_create_dir(name, parent);
2014 if (IS_ERR(dent))
2015 goto fail;
2016 } else
2017 dget(dent);
2018 ns_dir(ns) = dir = dent;
2019 error = __aafs_ns_mkdir_entries(ns, dir);
2020 if (error)
2021 goto fail2;
2022
2023 /* profiles */
2024 list_for_each_entry(child, &ns->base.profiles, base.list) {
2025 error = __aafs_profile_mkdir(child, ns_subprofs_dir(ns));
2026 if (error)
2027 goto fail2;
2028 }
2029
2030 /* subnamespaces */
2031 list_for_each_entry(sub, &ns->sub_ns, base.list) {
2032 mutex_lock_nested(&sub->lock, sub->level);
2033 error = __aafs_ns_mkdir(sub, ns_subns_dir(ns), NULL, NULL);
2034 mutex_unlock(&sub->lock);
2035 if (error)
2036 goto fail2;
2037 }
2038
2039 return 0;
2040
2041 fail:
2042 error = PTR_ERR(dent);
2043
2044 fail2:
2045 __aafs_ns_rmdir(ns);
2046
2047 return error;
2048 }
2049
2050 /**
2051 * __next_ns - find the next namespace to list
2052 * @root: root namespace to stop search at (NOT NULL)
2053 * @ns: current ns position (NOT NULL)
2054 *
2055 * Find the next namespace from @ns under @root and handle all locking needed
2056 * while switching current namespace.
2057 *
2058 * Returns: next namespace or NULL if at last namespace under @root
2059 * Requires: ns->parent->lock to be held
2060 * NOTE: will not unlock root->lock
2061 */
__next_ns(struct aa_ns * root,struct aa_ns * ns)2062 static struct aa_ns *__next_ns(struct aa_ns *root, struct aa_ns *ns)
2063 {
2064 struct aa_ns *parent, *next;
2065
2066 AA_BUG(!root);
2067 AA_BUG(!ns);
2068 AA_BUG(ns != root && !mutex_is_locked(&ns->parent->lock));
2069
2070 /* is next namespace a child */
2071 if (!list_empty(&ns->sub_ns)) {
2072 next = list_first_entry(&ns->sub_ns, typeof(*ns), base.list);
2073 mutex_lock_nested(&next->lock, next->level);
2074 return next;
2075 }
2076
2077 /* check if the next ns is a sibling, parent, gp, .. */
2078 parent = ns->parent;
2079 while (ns != root) {
2080 mutex_unlock(&ns->lock);
2081 next = list_next_entry(ns, base.list);
2082 if (!list_entry_is_head(next, &parent->sub_ns, base.list)) {
2083 mutex_lock_nested(&next->lock, next->level);
2084 return next;
2085 }
2086 ns = parent;
2087 parent = parent->parent;
2088 }
2089
2090 return NULL;
2091 }
2092
2093 /**
2094 * __first_profile - find the first profile in a namespace
2095 * @root: namespace that is root of profiles being displayed (NOT NULL)
2096 * @ns: namespace to start in (NOT NULL)
2097 *
2098 * Returns: unrefcounted profile or NULL if no profile
2099 * Requires: profile->ns.lock to be held
2100 */
__first_profile(struct aa_ns * root,struct aa_ns * ns)2101 static struct aa_profile *__first_profile(struct aa_ns *root,
2102 struct aa_ns *ns)
2103 {
2104 AA_BUG(!root);
2105 AA_BUG(ns && !mutex_is_locked(&ns->lock));
2106
2107 for (; ns; ns = __next_ns(root, ns)) {
2108 if (!list_empty(&ns->base.profiles))
2109 return list_first_entry(&ns->base.profiles,
2110 struct aa_profile, base.list);
2111 }
2112 return NULL;
2113 }
2114
2115 /**
2116 * __next_profile - step to the next profile in a profile tree
2117 * @profile: current profile in tree (NOT NULL)
2118 *
2119 * Perform a depth first traversal on the profile tree in a namespace
2120 *
2121 * Returns: next profile or NULL if done
2122 * Requires: profile->ns.lock to be held
2123 */
__next_profile(struct aa_profile * p)2124 static struct aa_profile *__next_profile(struct aa_profile *p)
2125 {
2126 struct aa_profile *parent;
2127 struct aa_ns *ns = p->ns;
2128
2129 AA_BUG(!mutex_is_locked(&profiles_ns(p)->lock));
2130
2131 /* is next profile a child */
2132 if (!list_empty(&p->base.profiles))
2133 return list_first_entry(&p->base.profiles, typeof(*p),
2134 base.list);
2135
2136 /* is next profile a sibling, parent sibling, gp, sibling, .. */
2137 parent = rcu_dereference_protected(p->parent,
2138 mutex_is_locked(&p->ns->lock));
2139 while (parent) {
2140 p = list_next_entry(p, base.list);
2141 if (!list_entry_is_head(p, &parent->base.profiles, base.list))
2142 return p;
2143 p = parent;
2144 parent = rcu_dereference_protected(parent->parent,
2145 mutex_is_locked(&parent->ns->lock));
2146 }
2147
2148 /* is next another profile in the namespace */
2149 p = list_next_entry(p, base.list);
2150 if (!list_entry_is_head(p, &ns->base.profiles, base.list))
2151 return p;
2152
2153 return NULL;
2154 }
2155
2156 /**
2157 * next_profile - step to the next profile in where ever it may be
2158 * @root: root namespace (NOT NULL)
2159 * @profile: current profile (NOT NULL)
2160 *
2161 * Returns: next profile or NULL if there isn't one
2162 */
next_profile(struct aa_ns * root,struct aa_profile * profile)2163 static struct aa_profile *next_profile(struct aa_ns *root,
2164 struct aa_profile *profile)
2165 {
2166 struct aa_profile *next = __next_profile(profile);
2167 if (next)
2168 return next;
2169
2170 /* finished all profiles in namespace move to next namespace */
2171 return __first_profile(root, __next_ns(root, profile->ns));
2172 }
2173
2174 /**
2175 * p_start - start a depth first traversal of profile tree
2176 * @f: seq_file to fill
2177 * @pos: current position
2178 *
2179 * Returns: first profile under current namespace or NULL if none found
2180 *
2181 * acquires first ns->lock
2182 */
p_start(struct seq_file * f,loff_t * pos)2183 static void *p_start(struct seq_file *f, loff_t *pos)
2184 {
2185 struct aa_profile *profile = NULL;
2186 struct aa_ns *root = aa_get_current_ns();
2187 loff_t l = *pos;
2188 f->private = root;
2189
2190 /* find the first profile */
2191 mutex_lock_nested(&root->lock, root->level);
2192 profile = __first_profile(root, root);
2193
2194 /* skip to position */
2195 for (; profile && l > 0; l--)
2196 profile = next_profile(root, profile);
2197
2198 return profile;
2199 }
2200
2201 /**
2202 * p_next - read the next profile entry
2203 * @f: seq_file to fill
2204 * @p: profile previously returned
2205 * @pos: current position
2206 *
2207 * Returns: next profile after @p or NULL if none
2208 *
2209 * may acquire/release locks in namespace tree as necessary
2210 */
p_next(struct seq_file * f,void * p,loff_t * pos)2211 static void *p_next(struct seq_file *f, void *p, loff_t *pos)
2212 {
2213 struct aa_profile *profile = p;
2214 struct aa_ns *ns = f->private;
2215 (*pos)++;
2216
2217 return next_profile(ns, profile);
2218 }
2219
2220 /**
2221 * p_stop - stop depth first traversal
2222 * @f: seq_file we are filling
2223 * @p: the last profile writen
2224 *
2225 * Release all locking done by p_start/p_next on namespace tree
2226 */
p_stop(struct seq_file * f,void * p)2227 static void p_stop(struct seq_file *f, void *p)
2228 {
2229 struct aa_profile *profile = p;
2230 struct aa_ns *root = f->private, *ns;
2231
2232 if (profile) {
2233 for (ns = profile->ns; ns && ns != root; ns = ns->parent)
2234 mutex_unlock(&ns->lock);
2235 }
2236 mutex_unlock(&root->lock);
2237 aa_put_ns(root);
2238 }
2239
2240 /**
2241 * seq_show_profile - show a profile entry
2242 * @f: seq_file to file
2243 * @p: current position (profile) (NOT NULL)
2244 *
2245 * Returns: error on failure
2246 */
seq_show_profile(struct seq_file * f,void * p)2247 static int seq_show_profile(struct seq_file *f, void *p)
2248 {
2249 struct aa_profile *profile = (struct aa_profile *)p;
2250 struct aa_ns *root = f->private;
2251
2252 aa_label_seq_xprint(f, root, &profile->label,
2253 FLAG_SHOW_MODE | FLAG_VIEW_SUBNS, GFP_KERNEL);
2254 seq_putc(f, '\n');
2255
2256 return 0;
2257 }
2258
2259 static const struct seq_operations aa_sfs_profiles_op = {
2260 .start = p_start,
2261 .next = p_next,
2262 .stop = p_stop,
2263 .show = seq_show_profile,
2264 };
2265
profiles_open(struct inode * inode,struct file * file)2266 static int profiles_open(struct inode *inode, struct file *file)
2267 {
2268 if (!policy_view_capable(NULL))
2269 return -EACCES;
2270
2271 return seq_open(file, &aa_sfs_profiles_op);
2272 }
2273
profiles_release(struct inode * inode,struct file * file)2274 static int profiles_release(struct inode *inode, struct file *file)
2275 {
2276 return seq_release(inode, file);
2277 }
2278
2279 static const struct file_operations aa_sfs_profiles_fops = {
2280 .open = profiles_open,
2281 .read = seq_read,
2282 .llseek = seq_lseek,
2283 .release = profiles_release,
2284 };
2285
2286
2287 /** Base file system setup **/
2288 static struct aa_sfs_entry aa_sfs_entry_file[] = {
2289 AA_SFS_FILE_STRING("mask",
2290 "create read write exec append mmap_exec link lock"),
2291 { }
2292 };
2293
2294 static struct aa_sfs_entry aa_sfs_entry_ptrace[] = {
2295 AA_SFS_FILE_STRING("mask", "read trace"),
2296 { }
2297 };
2298
2299 static struct aa_sfs_entry aa_sfs_entry_signal[] = {
2300 AA_SFS_FILE_STRING("mask", AA_SFS_SIG_MASK),
2301 { }
2302 };
2303
2304 static struct aa_sfs_entry aa_sfs_entry_attach[] = {
2305 AA_SFS_FILE_BOOLEAN("xattr", 1),
2306 { }
2307 };
2308 static struct aa_sfs_entry aa_sfs_entry_domain[] = {
2309 AA_SFS_FILE_BOOLEAN("change_hat", 1),
2310 AA_SFS_FILE_BOOLEAN("change_hatv", 1),
2311 AA_SFS_FILE_BOOLEAN("change_onexec", 1),
2312 AA_SFS_FILE_BOOLEAN("change_profile", 1),
2313 AA_SFS_FILE_BOOLEAN("stack", 1),
2314 AA_SFS_FILE_BOOLEAN("fix_binfmt_elf_mmap", 1),
2315 AA_SFS_FILE_BOOLEAN("post_nnp_subset", 1),
2316 AA_SFS_FILE_BOOLEAN("computed_longest_left", 1),
2317 AA_SFS_DIR("attach_conditions", aa_sfs_entry_attach),
2318 AA_SFS_FILE_STRING("version", "1.2"),
2319 { }
2320 };
2321
2322 static struct aa_sfs_entry aa_sfs_entry_versions[] = {
2323 AA_SFS_FILE_BOOLEAN("v5", 1),
2324 AA_SFS_FILE_BOOLEAN("v6", 1),
2325 AA_SFS_FILE_BOOLEAN("v7", 1),
2326 AA_SFS_FILE_BOOLEAN("v8", 1),
2327 { }
2328 };
2329
2330 static struct aa_sfs_entry aa_sfs_entry_policy[] = {
2331 AA_SFS_DIR("versions", aa_sfs_entry_versions),
2332 AA_SFS_FILE_BOOLEAN("set_load", 1),
2333 /* number of out of band transitions supported */
2334 AA_SFS_FILE_U64("outofband", MAX_OOB_SUPPORTED),
2335 { }
2336 };
2337
2338 static struct aa_sfs_entry aa_sfs_entry_mount[] = {
2339 AA_SFS_FILE_STRING("mask", "mount umount pivot_root"),
2340 { }
2341 };
2342
2343 static struct aa_sfs_entry aa_sfs_entry_ns[] = {
2344 AA_SFS_FILE_BOOLEAN("profile", 1),
2345 AA_SFS_FILE_BOOLEAN("pivot_root", 0),
2346 { }
2347 };
2348
2349 static struct aa_sfs_entry aa_sfs_entry_query_label[] = {
2350 AA_SFS_FILE_STRING("perms", "allow deny audit quiet"),
2351 AA_SFS_FILE_BOOLEAN("data", 1),
2352 AA_SFS_FILE_BOOLEAN("multi_transaction", 1),
2353 { }
2354 };
2355
2356 static struct aa_sfs_entry aa_sfs_entry_query[] = {
2357 AA_SFS_DIR("label", aa_sfs_entry_query_label),
2358 { }
2359 };
2360 static struct aa_sfs_entry aa_sfs_entry_features[] = {
2361 AA_SFS_DIR("policy", aa_sfs_entry_policy),
2362 AA_SFS_DIR("domain", aa_sfs_entry_domain),
2363 AA_SFS_DIR("file", aa_sfs_entry_file),
2364 AA_SFS_DIR("network_v8", aa_sfs_entry_network),
2365 AA_SFS_DIR("mount", aa_sfs_entry_mount),
2366 AA_SFS_DIR("namespaces", aa_sfs_entry_ns),
2367 AA_SFS_FILE_U64("capability", VFS_CAP_FLAGS_MASK),
2368 AA_SFS_DIR("rlimit", aa_sfs_entry_rlimit),
2369 AA_SFS_DIR("caps", aa_sfs_entry_caps),
2370 AA_SFS_DIR("ptrace", aa_sfs_entry_ptrace),
2371 AA_SFS_DIR("signal", aa_sfs_entry_signal),
2372 AA_SFS_DIR("query", aa_sfs_entry_query),
2373 { }
2374 };
2375
2376 static struct aa_sfs_entry aa_sfs_entry_apparmor[] = {
2377 AA_SFS_FILE_FOPS(".access", 0666, &aa_sfs_access),
2378 AA_SFS_FILE_FOPS(".stacked", 0444, &seq_ns_stacked_fops),
2379 AA_SFS_FILE_FOPS(".ns_stacked", 0444, &seq_ns_nsstacked_fops),
2380 AA_SFS_FILE_FOPS(".ns_level", 0444, &seq_ns_level_fops),
2381 AA_SFS_FILE_FOPS(".ns_name", 0444, &seq_ns_name_fops),
2382 AA_SFS_FILE_FOPS("profiles", 0444, &aa_sfs_profiles_fops),
2383 AA_SFS_DIR("features", aa_sfs_entry_features),
2384 { }
2385 };
2386
2387 static struct aa_sfs_entry aa_sfs_entry =
2388 AA_SFS_DIR("apparmor", aa_sfs_entry_apparmor);
2389
2390 /**
2391 * entry_create_file - create a file entry in the apparmor securityfs
2392 * @fs_file: aa_sfs_entry to build an entry for (NOT NULL)
2393 * @parent: the parent dentry in the securityfs
2394 *
2395 * Use entry_remove_file to remove entries created with this fn.
2396 */
entry_create_file(struct aa_sfs_entry * fs_file,struct dentry * parent)2397 static int __init entry_create_file(struct aa_sfs_entry *fs_file,
2398 struct dentry *parent)
2399 {
2400 int error = 0;
2401
2402 fs_file->dentry = securityfs_create_file(fs_file->name,
2403 S_IFREG | fs_file->mode,
2404 parent, fs_file,
2405 fs_file->file_ops);
2406 if (IS_ERR(fs_file->dentry)) {
2407 error = PTR_ERR(fs_file->dentry);
2408 fs_file->dentry = NULL;
2409 }
2410 return error;
2411 }
2412
2413 static void __init entry_remove_dir(struct aa_sfs_entry *fs_dir);
2414 /**
2415 * entry_create_dir - recursively create a directory entry in the securityfs
2416 * @fs_dir: aa_sfs_entry (and all child entries) to build (NOT NULL)
2417 * @parent: the parent dentry in the securityfs
2418 *
2419 * Use entry_remove_dir to remove entries created with this fn.
2420 */
entry_create_dir(struct aa_sfs_entry * fs_dir,struct dentry * parent)2421 static int __init entry_create_dir(struct aa_sfs_entry *fs_dir,
2422 struct dentry *parent)
2423 {
2424 struct aa_sfs_entry *fs_file;
2425 struct dentry *dir;
2426 int error;
2427
2428 dir = securityfs_create_dir(fs_dir->name, parent);
2429 if (IS_ERR(dir))
2430 return PTR_ERR(dir);
2431 fs_dir->dentry = dir;
2432
2433 for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) {
2434 if (fs_file->v_type == AA_SFS_TYPE_DIR)
2435 error = entry_create_dir(fs_file, fs_dir->dentry);
2436 else
2437 error = entry_create_file(fs_file, fs_dir->dentry);
2438 if (error)
2439 goto failed;
2440 }
2441
2442 return 0;
2443
2444 failed:
2445 entry_remove_dir(fs_dir);
2446
2447 return error;
2448 }
2449
2450 /**
2451 * entry_remove_file - drop a single file entry in the apparmor securityfs
2452 * @fs_file: aa_sfs_entry to detach from the securityfs (NOT NULL)
2453 */
entry_remove_file(struct aa_sfs_entry * fs_file)2454 static void __init entry_remove_file(struct aa_sfs_entry *fs_file)
2455 {
2456 if (!fs_file->dentry)
2457 return;
2458
2459 securityfs_remove(fs_file->dentry);
2460 fs_file->dentry = NULL;
2461 }
2462
2463 /**
2464 * entry_remove_dir - recursively drop a directory entry from the securityfs
2465 * @fs_dir: aa_sfs_entry (and all child entries) to detach (NOT NULL)
2466 */
entry_remove_dir(struct aa_sfs_entry * fs_dir)2467 static void __init entry_remove_dir(struct aa_sfs_entry *fs_dir)
2468 {
2469 struct aa_sfs_entry *fs_file;
2470
2471 for (fs_file = fs_dir->v.files; fs_file && fs_file->name; ++fs_file) {
2472 if (fs_file->v_type == AA_SFS_TYPE_DIR)
2473 entry_remove_dir(fs_file);
2474 else
2475 entry_remove_file(fs_file);
2476 }
2477
2478 entry_remove_file(fs_dir);
2479 }
2480
2481 /**
2482 * aa_destroy_aafs - cleanup and free aafs
2483 *
2484 * releases dentries allocated by aa_create_aafs
2485 */
aa_destroy_aafs(void)2486 void __init aa_destroy_aafs(void)
2487 {
2488 entry_remove_dir(&aa_sfs_entry);
2489 }
2490
2491
2492 #define NULL_FILE_NAME ".null"
2493 struct path aa_null;
2494
aa_mk_null_file(struct dentry * parent)2495 static int aa_mk_null_file(struct dentry *parent)
2496 {
2497 struct vfsmount *mount = NULL;
2498 struct dentry *dentry;
2499 struct inode *inode;
2500 int count = 0;
2501 int error = simple_pin_fs(parent->d_sb->s_type, &mount, &count);
2502
2503 if (error)
2504 return error;
2505
2506 inode_lock(d_inode(parent));
2507 dentry = lookup_one_len(NULL_FILE_NAME, parent, strlen(NULL_FILE_NAME));
2508 if (IS_ERR(dentry)) {
2509 error = PTR_ERR(dentry);
2510 goto out;
2511 }
2512 inode = new_inode(parent->d_inode->i_sb);
2513 if (!inode) {
2514 error = -ENOMEM;
2515 goto out1;
2516 }
2517
2518 inode->i_ino = get_next_ino();
2519 inode->i_mode = S_IFCHR | S_IRUGO | S_IWUGO;
2520 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(inode);
2521 init_special_inode(inode, S_IFCHR | S_IRUGO | S_IWUGO,
2522 MKDEV(MEM_MAJOR, 3));
2523 d_instantiate(dentry, inode);
2524 aa_null.dentry = dget(dentry);
2525 aa_null.mnt = mntget(mount);
2526
2527 error = 0;
2528
2529 out1:
2530 dput(dentry);
2531 out:
2532 inode_unlock(d_inode(parent));
2533 simple_release_fs(&mount, &count);
2534 return error;
2535 }
2536
2537
2538
policy_get_link(struct dentry * dentry,struct inode * inode,struct delayed_call * done)2539 static const char *policy_get_link(struct dentry *dentry,
2540 struct inode *inode,
2541 struct delayed_call *done)
2542 {
2543 struct aa_ns *ns;
2544 struct path path;
2545 int error;
2546
2547 if (!dentry)
2548 return ERR_PTR(-ECHILD);
2549
2550 ns = aa_get_current_ns();
2551 path.mnt = mntget(aafs_mnt);
2552 path.dentry = dget(ns_dir(ns));
2553 error = nd_jump_link(&path);
2554 aa_put_ns(ns);
2555
2556 return ERR_PTR(error);
2557 }
2558
policy_readlink(struct dentry * dentry,char __user * buffer,int buflen)2559 static int policy_readlink(struct dentry *dentry, char __user *buffer,
2560 int buflen)
2561 {
2562 char name[32];
2563 int res;
2564
2565 res = snprintf(name, sizeof(name), "%s:[%lu]", AAFS_NAME,
2566 d_inode(dentry)->i_ino);
2567 if (res > 0 && res < sizeof(name))
2568 res = readlink_copy(buffer, buflen, name);
2569 else
2570 res = -ENOENT;
2571
2572 return res;
2573 }
2574
2575 static const struct inode_operations policy_link_iops = {
2576 .readlink = policy_readlink,
2577 .get_link = policy_get_link,
2578 };
2579
2580
2581 /**
2582 * aa_create_aafs - create the apparmor security filesystem
2583 *
2584 * dentries created here are released by aa_destroy_aafs
2585 *
2586 * Returns: error on failure
2587 */
aa_create_aafs(void)2588 static int __init aa_create_aafs(void)
2589 {
2590 struct dentry *dent;
2591 int error;
2592
2593 if (!apparmor_initialized)
2594 return 0;
2595
2596 if (aa_sfs_entry.dentry) {
2597 AA_ERROR("%s: AppArmor securityfs already exists\n", __func__);
2598 return -EEXIST;
2599 }
2600
2601 /* setup apparmorfs used to virtualize policy/ */
2602 aafs_mnt = kern_mount(&aafs_ops);
2603 if (IS_ERR(aafs_mnt))
2604 panic("can't set apparmorfs up\n");
2605 aafs_mnt->mnt_sb->s_flags &= ~SB_NOUSER;
2606
2607 /* Populate fs tree. */
2608 error = entry_create_dir(&aa_sfs_entry, NULL);
2609 if (error)
2610 goto error;
2611
2612 dent = securityfs_create_file(".load", 0666, aa_sfs_entry.dentry,
2613 NULL, &aa_fs_profile_load);
2614 if (IS_ERR(dent))
2615 goto dent_error;
2616 ns_subload(root_ns) = dent;
2617
2618 dent = securityfs_create_file(".replace", 0666, aa_sfs_entry.dentry,
2619 NULL, &aa_fs_profile_replace);
2620 if (IS_ERR(dent))
2621 goto dent_error;
2622 ns_subreplace(root_ns) = dent;
2623
2624 dent = securityfs_create_file(".remove", 0666, aa_sfs_entry.dentry,
2625 NULL, &aa_fs_profile_remove);
2626 if (IS_ERR(dent))
2627 goto dent_error;
2628 ns_subremove(root_ns) = dent;
2629
2630 dent = securityfs_create_file("revision", 0444, aa_sfs_entry.dentry,
2631 NULL, &aa_fs_ns_revision_fops);
2632 if (IS_ERR(dent))
2633 goto dent_error;
2634 ns_subrevision(root_ns) = dent;
2635
2636 /* policy tree referenced by magic policy symlink */
2637 mutex_lock_nested(&root_ns->lock, root_ns->level);
2638 error = __aafs_ns_mkdir(root_ns, aafs_mnt->mnt_root, ".policy",
2639 aafs_mnt->mnt_root);
2640 mutex_unlock(&root_ns->lock);
2641 if (error)
2642 goto error;
2643
2644 /* magic symlink similar to nsfs redirects based on task policy */
2645 dent = securityfs_create_symlink("policy", aa_sfs_entry.dentry,
2646 NULL, &policy_link_iops);
2647 if (IS_ERR(dent))
2648 goto dent_error;
2649
2650 error = aa_mk_null_file(aa_sfs_entry.dentry);
2651 if (error)
2652 goto error;
2653
2654 /* TODO: add default profile to apparmorfs */
2655
2656 /* Report that AppArmor fs is enabled */
2657 aa_info_message("AppArmor Filesystem Enabled");
2658 return 0;
2659
2660 dent_error:
2661 error = PTR_ERR(dent);
2662 error:
2663 aa_destroy_aafs();
2664 AA_ERROR("Error creating AppArmor securityfs\n");
2665 return error;
2666 }
2667
2668 fs_initcall(aa_create_aafs);
2669