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TOMOYO Linux Cross Reference
Linux/security/apparmor/apparmorfs.c

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

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