TOMOYO: Use array of "struct list_head".
[linux-3.10.git] / security / tomoyo / common.c
1 /*
2  * security/tomoyo/common.c
3  *
4  * Common functions for TOMOYO.
5  *
6  * Copyright (C) 2005-2010  NTT DATA CORPORATION
7  */
8
9 #include <linux/uaccess.h>
10 #include <linux/slab.h>
11 #include <linux/security.h>
12 #include "common.h"
13
14 static struct tomoyo_profile tomoyo_default_profile = {
15         .learning = &tomoyo_default_profile.preference,
16         .permissive = &tomoyo_default_profile.preference,
17         .enforcing = &tomoyo_default_profile.preference,
18         .preference.enforcing_verbose = true,
19         .preference.learning_max_entry = 2048,
20         .preference.learning_verbose = false,
21         .preference.permissive_verbose = true
22 };
23
24 /* Profile version. Currently only 20090903 is defined. */
25 static unsigned int tomoyo_profile_version;
26
27 /* Profile table. Memory is allocated as needed. */
28 static struct tomoyo_profile *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
29
30 /* String table for functionality that takes 4 modes. */
31 static const char *tomoyo_mode_4[4] = {
32         "disabled", "learning", "permissive", "enforcing"
33 };
34
35 /* String table for /sys/kernel/security/tomoyo/profile */
36 static const char *tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
37                                        + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
38         [TOMOYO_MAC_FILE_EXECUTE]    = "file::execute",
39         [TOMOYO_MAC_FILE_OPEN]       = "file::open",
40         [TOMOYO_MAC_FILE_CREATE]     = "file::create",
41         [TOMOYO_MAC_FILE_UNLINK]     = "file::unlink",
42         [TOMOYO_MAC_FILE_MKDIR]      = "file::mkdir",
43         [TOMOYO_MAC_FILE_RMDIR]      = "file::rmdir",
44         [TOMOYO_MAC_FILE_MKFIFO]     = "file::mkfifo",
45         [TOMOYO_MAC_FILE_MKSOCK]     = "file::mksock",
46         [TOMOYO_MAC_FILE_TRUNCATE]   = "file::truncate",
47         [TOMOYO_MAC_FILE_SYMLINK]    = "file::symlink",
48         [TOMOYO_MAC_FILE_REWRITE]    = "file::rewrite",
49         [TOMOYO_MAC_FILE_MKBLOCK]    = "file::mkblock",
50         [TOMOYO_MAC_FILE_MKCHAR]     = "file::mkchar",
51         [TOMOYO_MAC_FILE_LINK]       = "file::link",
52         [TOMOYO_MAC_FILE_RENAME]     = "file::rename",
53         [TOMOYO_MAC_FILE_CHMOD]      = "file::chmod",
54         [TOMOYO_MAC_FILE_CHOWN]      = "file::chown",
55         [TOMOYO_MAC_FILE_CHGRP]      = "file::chgrp",
56         [TOMOYO_MAC_FILE_IOCTL]      = "file::ioctl",
57         [TOMOYO_MAC_FILE_CHROOT]     = "file::chroot",
58         [TOMOYO_MAC_FILE_MOUNT]      = "file::mount",
59         [TOMOYO_MAC_FILE_UMOUNT]     = "file::umount",
60         [TOMOYO_MAC_FILE_PIVOT_ROOT] = "file::pivot_root",
61         [TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
62 };
63
64 /* Permit policy management by non-root user? */
65 static bool tomoyo_manage_by_non_root;
66
67 /* Utility functions. */
68
69 /**
70  * tomoyo_yesno - Return "yes" or "no".
71  *
72  * @value: Bool value.
73  */
74 static const char *tomoyo_yesno(const unsigned int value)
75 {
76         return value ? "yes" : "no";
77 }
78
79 /**
80  * tomoyo_print_name_union - Print a tomoyo_name_union.
81  *
82  * @head: Pointer to "struct tomoyo_io_buffer".
83  * @ptr:  Pointer to "struct tomoyo_name_union".
84  *
85  * Returns true on success, false otherwise.
86  */
87 static bool tomoyo_print_name_union(struct tomoyo_io_buffer *head,
88                                  const struct tomoyo_name_union *ptr)
89 {
90         int pos = head->read_avail;
91         if (pos && head->read_buf[pos - 1] == ' ')
92                 head->read_avail--;
93         if (ptr->is_group)
94                 return tomoyo_io_printf(head, " @%s",
95                                         ptr->group->group_name->name);
96         return tomoyo_io_printf(head, " %s", ptr->filename->name);
97 }
98
99 /**
100  * tomoyo_print_number_union - Print a tomoyo_number_union.
101  *
102  * @head:       Pointer to "struct tomoyo_io_buffer".
103  * @ptr:        Pointer to "struct tomoyo_number_union".
104  *
105  * Returns true on success, false otherwise.
106  */
107 bool tomoyo_print_number_union(struct tomoyo_io_buffer *head,
108                                const struct tomoyo_number_union *ptr)
109 {
110         unsigned long min;
111         unsigned long max;
112         u8 min_type;
113         u8 max_type;
114         if (!tomoyo_io_printf(head, " "))
115                 return false;
116         if (ptr->is_group)
117                 return tomoyo_io_printf(head, "@%s",
118                                         ptr->group->group_name->name);
119         min_type = ptr->min_type;
120         max_type = ptr->max_type;
121         min = ptr->values[0];
122         max = ptr->values[1];
123         switch (min_type) {
124         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
125                 if (!tomoyo_io_printf(head, "0x%lX", min))
126                         return false;
127                 break;
128         case TOMOYO_VALUE_TYPE_OCTAL:
129                 if (!tomoyo_io_printf(head, "0%lo", min))
130                         return false;
131                 break;
132         default:
133                 if (!tomoyo_io_printf(head, "%lu", min))
134                         return false;
135                 break;
136         }
137         if (min == max && min_type == max_type)
138                 return true;
139         switch (max_type) {
140         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
141                 return tomoyo_io_printf(head, "-0x%lX", max);
142         case TOMOYO_VALUE_TYPE_OCTAL:
143                 return tomoyo_io_printf(head, "-0%lo", max);
144         default:
145                 return tomoyo_io_printf(head, "-%lu", max);
146         }
147 }
148
149 /**
150  * tomoyo_io_printf - Transactional printf() to "struct tomoyo_io_buffer" structure.
151  *
152  * @head: Pointer to "struct tomoyo_io_buffer".
153  * @fmt:  The printf()'s format string, followed by parameters.
154  *
155  * Returns true if output was written, false otherwise.
156  *
157  * The snprintf() will truncate, but tomoyo_io_printf() won't.
158  */
159 bool tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
160 {
161         va_list args;
162         int len;
163         int pos = head->read_avail;
164         int size = head->readbuf_size - pos;
165
166         if (size <= 0)
167                 return false;
168         va_start(args, fmt);
169         len = vsnprintf(head->read_buf + pos, size, fmt, args);
170         va_end(args);
171         if (pos + len >= head->readbuf_size)
172                 return false;
173         head->read_avail += len;
174         return true;
175 }
176
177 /**
178  * tomoyo_find_or_assign_new_profile - Create a new profile.
179  *
180  * @profile: Profile number to create.
181  *
182  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
183  */
184 static struct tomoyo_profile *tomoyo_find_or_assign_new_profile
185 (const unsigned int profile)
186 {
187         struct tomoyo_profile *ptr;
188         struct tomoyo_profile *entry;
189         if (profile >= TOMOYO_MAX_PROFILES)
190                 return NULL;
191         ptr = tomoyo_profile_ptr[profile];
192         if (ptr)
193                 return ptr;
194         entry = kzalloc(sizeof(*entry), GFP_NOFS);
195         if (mutex_lock_interruptible(&tomoyo_policy_lock))
196                 goto out;
197         ptr = tomoyo_profile_ptr[profile];
198         if (!ptr && tomoyo_memory_ok(entry)) {
199                 ptr = entry;
200                 ptr->learning = &tomoyo_default_profile.preference;
201                 ptr->permissive = &tomoyo_default_profile.preference;
202                 ptr->enforcing = &tomoyo_default_profile.preference;
203                 ptr->default_config = TOMOYO_CONFIG_DISABLED;
204                 memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
205                        sizeof(ptr->config));
206                 mb(); /* Avoid out-of-order execution. */
207                 tomoyo_profile_ptr[profile] = ptr;
208                 entry = NULL;
209         }
210         mutex_unlock(&tomoyo_policy_lock);
211  out:
212         kfree(entry);
213         return ptr;
214 }
215
216 /**
217  * tomoyo_profile - Find a profile.
218  *
219  * @profile: Profile number to find.
220  *
221  * Returns pointer to "struct tomoyo_profile".
222  */
223 struct tomoyo_profile *tomoyo_profile(const u8 profile)
224 {
225         struct tomoyo_profile *ptr = tomoyo_profile_ptr[profile];
226         if (!tomoyo_policy_loaded)
227                 return &tomoyo_default_profile;
228         BUG_ON(!ptr);
229         return ptr;
230 }
231
232 /**
233  * tomoyo_write_profile - Write profile table.
234  *
235  * @head: Pointer to "struct tomoyo_io_buffer".
236  *
237  * Returns 0 on success, negative value otherwise.
238  */
239 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
240 {
241         char *data = head->write_buf;
242         unsigned int i;
243         int value;
244         int mode;
245         u8 config;
246         bool use_default = false;
247         char *cp;
248         struct tomoyo_profile *profile;
249         if (sscanf(data, "PROFILE_VERSION=%u", &tomoyo_profile_version) == 1)
250                 return 0;
251         i = simple_strtoul(data, &cp, 10);
252         if (data == cp) {
253                 profile = &tomoyo_default_profile;
254         } else {
255                 if (*cp != '-')
256                         return -EINVAL;
257                 data = cp + 1;
258                 profile = tomoyo_find_or_assign_new_profile(i);
259                 if (!profile)
260                         return -EINVAL;
261         }
262         cp = strchr(data, '=');
263         if (!cp)
264                 return -EINVAL;
265         *cp++ = '\0';
266         if (profile != &tomoyo_default_profile)
267                 use_default = strstr(cp, "use_default") != NULL;
268         if (strstr(cp, "verbose=yes"))
269                 value = 1;
270         else if (strstr(cp, "verbose=no"))
271                 value = 0;
272         else
273                 value = -1;
274         if (!strcmp(data, "PREFERENCE::enforcing")) {
275                 if (use_default) {
276                         profile->enforcing = &tomoyo_default_profile.preference;
277                         return 0;
278                 }
279                 profile->enforcing = &profile->preference;
280                 if (value >= 0)
281                         profile->preference.enforcing_verbose = value;
282                 return 0;
283         }
284         if (!strcmp(data, "PREFERENCE::permissive")) {
285                 if (use_default) {
286                         profile->permissive = &tomoyo_default_profile.preference;
287                         return 0;
288                 }
289                 profile->permissive = &profile->preference;
290                 if (value >= 0)
291                         profile->preference.permissive_verbose = value;
292                 return 0;
293         }
294         if (!strcmp(data, "PREFERENCE::learning")) {
295                 char *cp2;
296                 if (use_default) {
297                         profile->learning = &tomoyo_default_profile.preference;
298                         return 0;
299                 }
300                 profile->learning = &profile->preference;
301                 if (value >= 0)
302                         profile->preference.learning_verbose = value;
303                 cp2 = strstr(cp, "max_entry=");
304                 if (cp2)
305                         sscanf(cp2 + 10, "%u",
306                                &profile->preference.learning_max_entry);
307                 return 0;
308         }
309         if (profile == &tomoyo_default_profile)
310                 return -EINVAL;
311         if (!strcmp(data, "COMMENT")) {
312                 const struct tomoyo_path_info *old_comment = profile->comment;
313                 profile->comment = tomoyo_get_name(cp);
314                 tomoyo_put_name(old_comment);
315                 return 0;
316         }
317         if (!strcmp(data, "CONFIG")) {
318                 i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
319                 config = profile->default_config;
320         } else if (tomoyo_str_starts(&data, "CONFIG::")) {
321                 config = 0;
322                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
323                         if (strcmp(data, tomoyo_mac_keywords[i]))
324                                 continue;
325                         config = profile->config[i];
326                         break;
327                 }
328                 if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
329                         return -EINVAL;
330         } else {
331                 return -EINVAL;
332         }
333         if (use_default) {
334                 config = TOMOYO_CONFIG_USE_DEFAULT;
335         } else {
336                 for (mode = 3; mode >= 0; mode--)
337                         if (strstr(cp, tomoyo_mode_4[mode]))
338                                 /*
339                                  * Update lower 3 bits in order to distinguish
340                                  * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
341                                  */
342                                 config = (config & ~7) | mode;
343         }
344         if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
345                 profile->config[i] = config;
346         else if (config != TOMOYO_CONFIG_USE_DEFAULT)
347                 profile->default_config = config;
348         return 0;
349 }
350
351 /**
352  * tomoyo_read_profile - Read profile table.
353  *
354  * @head: Pointer to "struct tomoyo_io_buffer".
355  */
356 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
357 {
358         int index;
359         if (head->read_eof)
360                 return;
361         if (head->read_bit)
362                 goto body;
363         tomoyo_io_printf(head, "PROFILE_VERSION=%s\n", "20090903");
364         tomoyo_io_printf(head, "PREFERENCE::learning={ verbose=%s "
365                          "max_entry=%u }\n",
366                          tomoyo_yesno(tomoyo_default_profile.preference.
367                                       learning_verbose),
368                          tomoyo_default_profile.preference.learning_max_entry);
369         tomoyo_io_printf(head, "PREFERENCE::permissive={ verbose=%s }\n",
370                          tomoyo_yesno(tomoyo_default_profile.preference.
371                                       permissive_verbose));
372         tomoyo_io_printf(head, "PREFERENCE::enforcing={ verbose=%s }\n",
373                          tomoyo_yesno(tomoyo_default_profile.preference.
374                                       enforcing_verbose));
375         head->read_bit = 1;
376  body:
377         for (index = head->read_step; index < TOMOYO_MAX_PROFILES; index++) {
378                 bool done;
379                 u8 config;
380                 int i;
381                 int pos;
382                 const struct tomoyo_profile *profile
383                         = tomoyo_profile_ptr[index];
384                 const struct tomoyo_path_info *comment;
385                 head->read_step = index;
386                 if (!profile)
387                         continue;
388                 pos = head->read_avail;
389                 comment = profile->comment;
390                 done = tomoyo_io_printf(head, "%u-COMMENT=%s\n", index,
391                                         comment ? comment->name : "");
392                 if (!done)
393                         goto out;
394                 config = profile->default_config;
395                 if (!tomoyo_io_printf(head, "%u-CONFIG={ mode=%s }\n", index,
396                                       tomoyo_mode_4[config & 3]))
397                         goto out;
398                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX +
399                              TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
400                         config = profile->config[i];
401                         if (config == TOMOYO_CONFIG_USE_DEFAULT)
402                                 continue;
403                         if (!tomoyo_io_printf(head,
404                                               "%u-CONFIG::%s={ mode=%s }\n",
405                                               index, tomoyo_mac_keywords[i],
406                                               tomoyo_mode_4[config & 3]))
407                                 goto out;
408                 }
409                 if (profile->learning != &tomoyo_default_profile.preference &&
410                     !tomoyo_io_printf(head, "%u-PREFERENCE::learning={ "
411                                       "verbose=%s max_entry=%u }\n", index,
412                                       tomoyo_yesno(profile->preference.
413                                                    learning_verbose),
414                                       profile->preference.learning_max_entry))
415                         goto out;
416                 if (profile->permissive != &tomoyo_default_profile.preference
417                     && !tomoyo_io_printf(head, "%u-PREFERENCE::permissive={ "
418                                          "verbose=%s }\n", index,
419                                          tomoyo_yesno(profile->preference.
420                                                       permissive_verbose)))
421                         goto out;
422                 if (profile->enforcing != &tomoyo_default_profile.preference &&
423                     !tomoyo_io_printf(head, "%u-PREFERENCE::enforcing={ "
424                                       "verbose=%s }\n", index,
425                                       tomoyo_yesno(profile->preference.
426                                                    enforcing_verbose)))
427                         goto out;
428                 continue;
429  out:
430                 head->read_avail = pos;
431                 break;
432         }
433         if (index == TOMOYO_MAX_PROFILES)
434                 head->read_eof = true;
435 }
436
437 static bool tomoyo_same_manager_entry(const struct tomoyo_acl_head *a,
438                                       const struct tomoyo_acl_head *b)
439 {
440         return container_of(a, struct tomoyo_policy_manager_entry, head)
441                 ->manager ==
442                 container_of(b, struct tomoyo_policy_manager_entry, head)
443                 ->manager;
444 }
445
446 /**
447  * tomoyo_update_manager_entry - Add a manager entry.
448  *
449  * @manager:   The path to manager or the domainnamme.
450  * @is_delete: True if it is a delete request.
451  *
452  * Returns 0 on success, negative value otherwise.
453  *
454  * Caller holds tomoyo_read_lock().
455  */
456 static int tomoyo_update_manager_entry(const char *manager,
457                                        const bool is_delete)
458 {
459         struct tomoyo_policy_manager_entry e = { };
460         int error;
461
462         if (tomoyo_domain_def(manager)) {
463                 if (!tomoyo_correct_domain(manager))
464                         return -EINVAL;
465                 e.is_domain = true;
466         } else {
467                 if (!tomoyo_correct_path(manager))
468                         return -EINVAL;
469         }
470         e.manager = tomoyo_get_name(manager);
471         if (!e.manager)
472                 return -ENOMEM;
473         error = tomoyo_update_policy(&e.head, sizeof(e), is_delete,
474                                      &tomoyo_policy_list[TOMOYO_ID_MANAGER],
475                                      tomoyo_same_manager_entry);
476         tomoyo_put_name(e.manager);
477         return error;
478 }
479
480 /**
481  * tomoyo_write_manager_policy - Write manager policy.
482  *
483  * @head: Pointer to "struct tomoyo_io_buffer".
484  *
485  * Returns 0 on success, negative value otherwise.
486  *
487  * Caller holds tomoyo_read_lock().
488  */
489 static int tomoyo_write_manager_policy(struct tomoyo_io_buffer *head)
490 {
491         char *data = head->write_buf;
492         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
493
494         if (!strcmp(data, "manage_by_non_root")) {
495                 tomoyo_manage_by_non_root = !is_delete;
496                 return 0;
497         }
498         return tomoyo_update_manager_entry(data, is_delete);
499 }
500
501 /**
502  * tomoyo_read_manager_policy - Read manager policy.
503  *
504  * @head: Pointer to "struct tomoyo_io_buffer".
505  *
506  * Caller holds tomoyo_read_lock().
507  */
508 static void tomoyo_read_manager_policy(struct tomoyo_io_buffer *head)
509 {
510         struct list_head *pos;
511         bool done = true;
512
513         if (head->read_eof)
514                 return;
515         list_for_each_cookie(pos, head->read_var2,
516                              &tomoyo_policy_list[TOMOYO_ID_MANAGER]) {
517                 struct tomoyo_policy_manager_entry *ptr;
518                 ptr = list_entry(pos, struct tomoyo_policy_manager_entry,
519                                  head.list);
520                 if (ptr->head.is_deleted)
521                         continue;
522                 done = tomoyo_io_printf(head, "%s\n", ptr->manager->name);
523                 if (!done)
524                         break;
525         }
526         head->read_eof = done;
527 }
528
529 /**
530  * tomoyo_policy_manager - Check whether the current process is a policy manager.
531  *
532  * Returns true if the current process is permitted to modify policy
533  * via /sys/kernel/security/tomoyo/ interface.
534  *
535  * Caller holds tomoyo_read_lock().
536  */
537 static bool tomoyo_policy_manager(void)
538 {
539         struct tomoyo_policy_manager_entry *ptr;
540         const char *exe;
541         const struct task_struct *task = current;
542         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
543         bool found = false;
544
545         if (!tomoyo_policy_loaded)
546                 return true;
547         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
548                 return false;
549         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
550                                 head.list) {
551                 if (!ptr->head.is_deleted && ptr->is_domain
552                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
553                         found = true;
554                         break;
555                 }
556         }
557         if (found)
558                 return true;
559         exe = tomoyo_get_exe();
560         if (!exe)
561                 return false;
562         list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
563                                 head.list) {
564                 if (!ptr->head.is_deleted && !ptr->is_domain
565                     && !strcmp(exe, ptr->manager->name)) {
566                         found = true;
567                         break;
568                 }
569         }
570         if (!found) { /* Reduce error messages. */
571                 static pid_t last_pid;
572                 const pid_t pid = current->pid;
573                 if (last_pid != pid) {
574                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
575                                "update policies.\n", domainname->name, exe);
576                         last_pid = pid;
577                 }
578         }
579         kfree(exe);
580         return found;
581 }
582
583 /**
584  * tomoyo_select_one - Parse select command.
585  *
586  * @head: Pointer to "struct tomoyo_io_buffer".
587  * @data: String to parse.
588  *
589  * Returns true on success, false otherwise.
590  *
591  * Caller holds tomoyo_read_lock().
592  */
593 static bool tomoyo_select_one(struct tomoyo_io_buffer *head,
594                                  const char *data)
595 {
596         unsigned int pid;
597         struct tomoyo_domain_info *domain = NULL;
598         bool global_pid = false;
599
600         if (sscanf(data, "pid=%u", &pid) == 1 ||
601             (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
602                 struct task_struct *p;
603                 rcu_read_lock();
604                 read_lock(&tasklist_lock);
605                 if (global_pid)
606                         p = find_task_by_pid_ns(pid, &init_pid_ns);
607                 else
608                         p = find_task_by_vpid(pid);
609                 if (p)
610                         domain = tomoyo_real_domain(p);
611                 read_unlock(&tasklist_lock);
612                 rcu_read_unlock();
613         } else if (!strncmp(data, "domain=", 7)) {
614                 if (tomoyo_domain_def(data + 7))
615                         domain = tomoyo_find_domain(data + 7);
616         } else
617                 return false;
618         head->write_var1 = domain;
619         /* Accessing read_buf is safe because head->io_sem is held. */
620         if (!head->read_buf)
621                 return true; /* Do nothing if open(O_WRONLY). */
622         head->read_avail = 0;
623         tomoyo_io_printf(head, "# select %s\n", data);
624         head->read_single_domain = true;
625         head->read_eof = !domain;
626         if (domain) {
627                 struct tomoyo_domain_info *d;
628                 head->read_var1 = NULL;
629                 list_for_each_entry_rcu(d, &tomoyo_domain_list, list) {
630                         if (d == domain)
631                                 break;
632                         head->read_var1 = &d->list;
633                 }
634                 head->read_var2 = NULL;
635                 head->read_bit = 0;
636                 head->read_step = 0;
637                 if (domain->is_deleted)
638                         tomoyo_io_printf(head, "# This is a deleted domain.\n");
639         }
640         return true;
641 }
642
643 /**
644  * tomoyo_delete_domain - Delete a domain.
645  *
646  * @domainname: The name of domain.
647  *
648  * Returns 0.
649  *
650  * Caller holds tomoyo_read_lock().
651  */
652 static int tomoyo_delete_domain(char *domainname)
653 {
654         struct tomoyo_domain_info *domain;
655         struct tomoyo_path_info name;
656
657         name.name = domainname;
658         tomoyo_fill_path_info(&name);
659         if (mutex_lock_interruptible(&tomoyo_policy_lock))
660                 return 0;
661         /* Is there an active domain? */
662         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
663                 /* Never delete tomoyo_kernel_domain */
664                 if (domain == &tomoyo_kernel_domain)
665                         continue;
666                 if (domain->is_deleted ||
667                     tomoyo_pathcmp(domain->domainname, &name))
668                         continue;
669                 domain->is_deleted = true;
670                 break;
671         }
672         mutex_unlock(&tomoyo_policy_lock);
673         return 0;
674 }
675
676 /**
677  * tomoyo_write_domain_policy2 - Write domain policy.
678  *
679  * @head: Pointer to "struct tomoyo_io_buffer".
680  *
681  * Returns 0 on success, negative value otherwise.
682  *
683  * Caller holds tomoyo_read_lock().
684  */
685 static int tomoyo_write_domain_policy2(char *data,
686                                        struct tomoyo_domain_info *domain,
687                                        const bool is_delete)
688 {
689         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
690                 return tomoyo_write_mount_policy(data, domain, is_delete);
691         return tomoyo_write_file_policy(data, domain, is_delete);
692 }
693
694 /**
695  * tomoyo_write_domain_policy - Write domain policy.
696  *
697  * @head: Pointer to "struct tomoyo_io_buffer".
698  *
699  * Returns 0 on success, negative value otherwise.
700  *
701  * Caller holds tomoyo_read_lock().
702  */
703 static int tomoyo_write_domain_policy(struct tomoyo_io_buffer *head)
704 {
705         char *data = head->write_buf;
706         struct tomoyo_domain_info *domain = head->write_var1;
707         bool is_delete = false;
708         bool is_select = false;
709         unsigned int profile;
710
711         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE))
712                 is_delete = true;
713         else if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_SELECT))
714                 is_select = true;
715         if (is_select && tomoyo_select_one(head, data))
716                 return 0;
717         /* Don't allow updating policies by non manager programs. */
718         if (!tomoyo_policy_manager())
719                 return -EPERM;
720         if (tomoyo_domain_def(data)) {
721                 domain = NULL;
722                 if (is_delete)
723                         tomoyo_delete_domain(data);
724                 else if (is_select)
725                         domain = tomoyo_find_domain(data);
726                 else
727                         domain = tomoyo_find_or_assign_new_domain(data, 0);
728                 head->write_var1 = domain;
729                 return 0;
730         }
731         if (!domain)
732                 return -EINVAL;
733
734         if (sscanf(data, TOMOYO_KEYWORD_USE_PROFILE "%u", &profile) == 1
735             && profile < TOMOYO_MAX_PROFILES) {
736                 if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
737                         domain->profile = (u8) profile;
738                 return 0;
739         }
740         if (!strcmp(data, TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
741                 domain->ignore_global_allow_read = !is_delete;
742                 return 0;
743         }
744         if (!strcmp(data, TOMOYO_KEYWORD_QUOTA_EXCEEDED)) {
745                 domain->quota_warned = !is_delete;
746                 return 0;
747         }
748         if (!strcmp(data, TOMOYO_KEYWORD_TRANSITION_FAILED)) {
749                 domain->transition_failed = !is_delete;
750                 return 0;
751         }
752         return tomoyo_write_domain_policy2(data, domain, is_delete);
753 }
754
755 /**
756  * tomoyo_print_path_acl - Print a single path ACL entry.
757  *
758  * @head: Pointer to "struct tomoyo_io_buffer".
759  * @ptr:  Pointer to "struct tomoyo_path_acl".
760  *
761  * Returns true on success, false otherwise.
762  */
763 static bool tomoyo_print_path_acl(struct tomoyo_io_buffer *head,
764                                   struct tomoyo_path_acl *ptr)
765 {
766         int pos;
767         u8 bit;
768         const u16 perm = ptr->perm;
769
770         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
771                 if (!(perm & (1 << bit)))
772                         continue;
773                 /* Print "read/write" instead of "read" and "write". */
774                 if ((bit == TOMOYO_TYPE_READ || bit == TOMOYO_TYPE_WRITE)
775                     && (perm & (1 << TOMOYO_TYPE_READ_WRITE)))
776                         continue;
777                 pos = head->read_avail;
778                 if (!tomoyo_io_printf(head, "allow_%s ",
779                                       tomoyo_path_keyword[bit]) ||
780                     !tomoyo_print_name_union(head, &ptr->name) ||
781                     !tomoyo_io_printf(head, "\n"))
782                         goto out;
783         }
784         head->read_bit = 0;
785         return true;
786  out:
787         head->read_bit = bit;
788         head->read_avail = pos;
789         return false;
790 }
791
792 /**
793  * tomoyo_print_path2_acl - Print a double path ACL entry.
794  *
795  * @head: Pointer to "struct tomoyo_io_buffer".
796  * @ptr:  Pointer to "struct tomoyo_path2_acl".
797  *
798  * Returns true on success, false otherwise.
799  */
800 static bool tomoyo_print_path2_acl(struct tomoyo_io_buffer *head,
801                                    struct tomoyo_path2_acl *ptr)
802 {
803         int pos;
804         const u8 perm = ptr->perm;
805         u8 bit;
806
807         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
808                 if (!(perm & (1 << bit)))
809                         continue;
810                 pos = head->read_avail;
811                 if (!tomoyo_io_printf(head, "allow_%s ",
812                                       tomoyo_path2_keyword[bit]) ||
813                     !tomoyo_print_name_union(head, &ptr->name1) ||
814                     !tomoyo_print_name_union(head, &ptr->name2) ||
815                     !tomoyo_io_printf(head, "\n"))
816                         goto out;
817         }
818         head->read_bit = 0;
819         return true;
820  out:
821         head->read_bit = bit;
822         head->read_avail = pos;
823         return false;
824 }
825
826 /**
827  * tomoyo_print_path_number_acl - Print a path_number ACL entry.
828  *
829  * @head: Pointer to "struct tomoyo_io_buffer".
830  * @ptr:  Pointer to "struct tomoyo_path_number_acl".
831  *
832  * Returns true on success, false otherwise.
833  */
834 static bool tomoyo_print_path_number_acl(struct tomoyo_io_buffer *head,
835                                          struct tomoyo_path_number_acl *ptr)
836 {
837         int pos;
838         u8 bit;
839         const u8 perm = ptr->perm;
840         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION;
841              bit++) {
842                 if (!(perm & (1 << bit)))
843                         continue;
844                 pos = head->read_avail;
845                 if (!tomoyo_io_printf(head, "allow_%s",
846                                       tomoyo_path_number_keyword[bit]) ||
847                     !tomoyo_print_name_union(head, &ptr->name) ||
848                     !tomoyo_print_number_union(head, &ptr->number) ||
849                     !tomoyo_io_printf(head, "\n"))
850                         goto out;
851         }
852         head->read_bit = 0;
853         return true;
854  out:
855         head->read_bit = bit;
856         head->read_avail = pos;
857         return false;
858 }
859
860 /**
861  * tomoyo_print_mkdev_acl - Print a mkdev ACL entry.
862  *
863  * @head: Pointer to "struct tomoyo_io_buffer".
864  * @ptr:  Pointer to "struct tomoyo_mkdev_acl".
865  *
866  * Returns true on success, false otherwise.
867  */
868 static bool tomoyo_print_mkdev_acl(struct tomoyo_io_buffer *head,
869                                           struct tomoyo_mkdev_acl *ptr)
870 {
871         int pos;
872         u8 bit;
873         const u16 perm = ptr->perm;
874         for (bit = head->read_bit; bit < TOMOYO_MAX_MKDEV_OPERATION;
875              bit++) {
876                 if (!(perm & (1 << bit)))
877                         continue;
878                 pos = head->read_avail;
879                 if (!tomoyo_io_printf(head, "allow_%s",
880                                       tomoyo_mkdev_keyword[bit]) ||
881                     !tomoyo_print_name_union(head, &ptr->name) ||
882                     !tomoyo_print_number_union(head, &ptr->mode) ||
883                     !tomoyo_print_number_union(head, &ptr->major) ||
884                     !tomoyo_print_number_union(head, &ptr->minor) ||
885                     !tomoyo_io_printf(head, "\n"))
886                         goto out;
887         }
888         head->read_bit = 0;
889         return true;
890  out:
891         head->read_bit = bit;
892         head->read_avail = pos;
893         return false;
894 }
895
896 /**
897  * tomoyo_print_mount_acl - Print a mount ACL entry.
898  *
899  * @head: Pointer to "struct tomoyo_io_buffer".
900  * @ptr:  Pointer to "struct tomoyo_mount_acl".
901  *
902  * Returns true on success, false otherwise.
903  */
904 static bool tomoyo_print_mount_acl(struct tomoyo_io_buffer *head,
905                                    struct tomoyo_mount_acl *ptr)
906 {
907         const int pos = head->read_avail;
908         if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_MOUNT) ||
909             !tomoyo_print_name_union(head, &ptr->dev_name) ||
910             !tomoyo_print_name_union(head, &ptr->dir_name) ||
911             !tomoyo_print_name_union(head, &ptr->fs_type) ||
912             !tomoyo_print_number_union(head, &ptr->flags) ||
913             !tomoyo_io_printf(head, "\n")) {
914                 head->read_avail = pos;
915                 return false;
916         }
917         return true;
918 }
919
920 /**
921  * tomoyo_print_entry - Print an ACL entry.
922  *
923  * @head: Pointer to "struct tomoyo_io_buffer".
924  * @ptr:  Pointer to an ACL entry.
925  *
926  * Returns true on success, false otherwise.
927  */
928 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
929                                struct tomoyo_acl_info *ptr)
930 {
931         const u8 acl_type = ptr->type;
932
933         if (ptr->is_deleted)
934                 return true;
935         if (acl_type == TOMOYO_TYPE_PATH_ACL) {
936                 struct tomoyo_path_acl *acl
937                         = container_of(ptr, struct tomoyo_path_acl, head);
938                 return tomoyo_print_path_acl(head, acl);
939         }
940         if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
941                 struct tomoyo_path2_acl *acl
942                         = container_of(ptr, struct tomoyo_path2_acl, head);
943                 return tomoyo_print_path2_acl(head, acl);
944         }
945         if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
946                 struct tomoyo_path_number_acl *acl
947                         = container_of(ptr, struct tomoyo_path_number_acl,
948                                        head);
949                 return tomoyo_print_path_number_acl(head, acl);
950         }
951         if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
952                 struct tomoyo_mkdev_acl *acl
953                         = container_of(ptr, struct tomoyo_mkdev_acl,
954                                        head);
955                 return tomoyo_print_mkdev_acl(head, acl);
956         }
957         if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
958                 struct tomoyo_mount_acl *acl
959                         = container_of(ptr, struct tomoyo_mount_acl, head);
960                 return tomoyo_print_mount_acl(head, acl);
961         }
962         BUG(); /* This must not happen. */
963         return false;
964 }
965
966 /**
967  * tomoyo_read_domain_policy - Read domain policy.
968  *
969  * @head: Pointer to "struct tomoyo_io_buffer".
970  *
971  * Caller holds tomoyo_read_lock().
972  */
973 static void tomoyo_read_domain_policy(struct tomoyo_io_buffer *head)
974 {
975         struct list_head *dpos;
976         struct list_head *apos;
977         bool done = true;
978
979         if (head->read_eof)
980                 return;
981         if (head->read_step == 0)
982                 head->read_step = 1;
983         list_for_each_cookie(dpos, head->read_var1, &tomoyo_domain_list) {
984                 struct tomoyo_domain_info *domain;
985                 const char *quota_exceeded = "";
986                 const char *transition_failed = "";
987                 const char *ignore_global_allow_read = "";
988                 domain = list_entry(dpos, struct tomoyo_domain_info, list);
989                 if (head->read_step != 1)
990                         goto acl_loop;
991                 if (domain->is_deleted && !head->read_single_domain)
992                         continue;
993                 /* Print domainname and flags. */
994                 if (domain->quota_warned)
995                         quota_exceeded = "quota_exceeded\n";
996                 if (domain->transition_failed)
997                         transition_failed = "transition_failed\n";
998                 if (domain->ignore_global_allow_read)
999                         ignore_global_allow_read
1000                                 = TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n";
1001                 done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE
1002                                         "%u\n%s%s%s\n",
1003                                         domain->domainname->name,
1004                                         domain->profile, quota_exceeded,
1005                                         transition_failed,
1006                                         ignore_global_allow_read);
1007                 if (!done)
1008                         break;
1009                 head->read_step = 2;
1010 acl_loop:
1011                 if (head->read_step == 3)
1012                         goto tail_mark;
1013                 /* Print ACL entries in the domain. */
1014                 list_for_each_cookie(apos, head->read_var2,
1015                                      &domain->acl_info_list) {
1016                         struct tomoyo_acl_info *ptr
1017                                 = list_entry(apos, struct tomoyo_acl_info,
1018                                              list);
1019                         done = tomoyo_print_entry(head, ptr);
1020                         if (!done)
1021                                 break;
1022                 }
1023                 if (!done)
1024                         break;
1025                 head->read_step = 3;
1026 tail_mark:
1027                 done = tomoyo_io_printf(head, "\n");
1028                 if (!done)
1029                         break;
1030                 head->read_step = 1;
1031                 if (head->read_single_domain)
1032                         break;
1033         }
1034         head->read_eof = done;
1035 }
1036
1037 /**
1038  * tomoyo_write_domain_profile - Assign profile for specified domain.
1039  *
1040  * @head: Pointer to "struct tomoyo_io_buffer".
1041  *
1042  * Returns 0 on success, -EINVAL otherwise.
1043  *
1044  * This is equivalent to doing
1045  *
1046  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
1047  *     /usr/sbin/tomoyo-loadpolicy -d
1048  *
1049  * Caller holds tomoyo_read_lock().
1050  */
1051 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
1052 {
1053         char *data = head->write_buf;
1054         char *cp = strchr(data, ' ');
1055         struct tomoyo_domain_info *domain;
1056         unsigned long profile;
1057
1058         if (!cp)
1059                 return -EINVAL;
1060         *cp = '\0';
1061         domain = tomoyo_find_domain(cp + 1);
1062         if (strict_strtoul(data, 10, &profile))
1063                 return -EINVAL;
1064         if (domain && profile < TOMOYO_MAX_PROFILES
1065             && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
1066                 domain->profile = (u8) profile;
1067         return 0;
1068 }
1069
1070 /**
1071  * tomoyo_read_domain_profile - Read only domainname and profile.
1072  *
1073  * @head: Pointer to "struct tomoyo_io_buffer".
1074  *
1075  * Returns list of profile number and domainname pairs.
1076  *
1077  * This is equivalent to doing
1078  *
1079  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
1080  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
1081  *     domainname = $0; } else if ( $1 == "use_profile" ) {
1082  *     print $2 " " domainname; domainname = ""; } } ; '
1083  *
1084  * Caller holds tomoyo_read_lock().
1085  */
1086 static void tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
1087 {
1088         struct list_head *pos;
1089         bool done = true;
1090
1091         if (head->read_eof)
1092                 return;
1093         list_for_each_cookie(pos, head->read_var1, &tomoyo_domain_list) {
1094                 struct tomoyo_domain_info *domain;
1095                 domain = list_entry(pos, struct tomoyo_domain_info, list);
1096                 if (domain->is_deleted)
1097                         continue;
1098                 done = tomoyo_io_printf(head, "%u %s\n", domain->profile,
1099                                         domain->domainname->name);
1100                 if (!done)
1101                         break;
1102         }
1103         head->read_eof = done;
1104 }
1105
1106 /**
1107  * tomoyo_write_pid: Specify PID to obtain domainname.
1108  *
1109  * @head: Pointer to "struct tomoyo_io_buffer".
1110  *
1111  * Returns 0.
1112  */
1113 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1114 {
1115         unsigned long pid;
1116         /* No error check. */
1117         strict_strtoul(head->write_buf, 10, &pid);
1118         head->read_step = (int) pid;
1119         head->read_eof = false;
1120         return 0;
1121 }
1122
1123 /**
1124  * tomoyo_read_pid - Get domainname of the specified PID.
1125  *
1126  * @head: Pointer to "struct tomoyo_io_buffer".
1127  *
1128  * Returns the domainname which the specified PID is in on success,
1129  * empty string otherwise.
1130  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1131  * using read()/write() interface rather than sysctl() interface.
1132  */
1133 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1134 {
1135         if (head->read_avail == 0 && !head->read_eof) {
1136                 const int pid = head->read_step;
1137                 struct task_struct *p;
1138                 struct tomoyo_domain_info *domain = NULL;
1139                 rcu_read_lock();
1140                 read_lock(&tasklist_lock);
1141                 p = find_task_by_vpid(pid);
1142                 if (p)
1143                         domain = tomoyo_real_domain(p);
1144                 read_unlock(&tasklist_lock);
1145                 rcu_read_unlock();
1146                 if (domain)
1147                         tomoyo_io_printf(head, "%d %u %s", pid, domain->profile,
1148                                          domain->domainname->name);
1149                 head->read_eof = true;
1150         }
1151 }
1152
1153 /**
1154  * tomoyo_write_exception_policy - Write exception policy.
1155  *
1156  * @head: Pointer to "struct tomoyo_io_buffer".
1157  *
1158  * Returns 0 on success, negative value otherwise.
1159  *
1160  * Caller holds tomoyo_read_lock().
1161  */
1162 static int tomoyo_write_exception_policy(struct tomoyo_io_buffer *head)
1163 {
1164         char *data = head->write_buf;
1165         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
1166
1167         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_KEEP_DOMAIN))
1168                 return tomoyo_write_domain_keeper_policy(data, false,
1169                                                          is_delete);
1170         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_KEEP_DOMAIN))
1171                 return tomoyo_write_domain_keeper_policy(data, true, is_delete);
1172         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_INITIALIZE_DOMAIN))
1173                 return tomoyo_write_domain_initializer_policy(data, false,
1174                                                               is_delete);
1175         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN))
1176                 return tomoyo_write_domain_initializer_policy(data, true,
1177                                                               is_delete);
1178         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_AGGREGATOR))
1179                 return tomoyo_write_aggregator_policy(data, is_delete);
1180         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALIAS))
1181                 return tomoyo_write_alias_policy(data, is_delete);
1182         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_READ))
1183                 return tomoyo_write_globally_readable_policy(data, is_delete);
1184         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_FILE_PATTERN))
1185                 return tomoyo_write_pattern_policy(data, is_delete);
1186         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DENY_REWRITE))
1187                 return tomoyo_write_no_rewrite_policy(data, is_delete);
1188         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_PATH_GROUP))
1189                 return tomoyo_write_path_group_policy(data, is_delete);
1190         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NUMBER_GROUP))
1191                 return tomoyo_write_number_group_policy(data, is_delete);
1192         return -EINVAL;
1193 }
1194
1195 /**
1196  * tomoyo_read_exception_policy - Read exception policy.
1197  *
1198  * @head: Pointer to "struct tomoyo_io_buffer".
1199  *
1200  * Caller holds tomoyo_read_lock().
1201  */
1202 static void tomoyo_read_exception_policy(struct tomoyo_io_buffer *head)
1203 {
1204         if (!head->read_eof) {
1205                 switch (head->read_step) {
1206                 case 0:
1207                         head->read_var2 = NULL;
1208                         head->read_step = 1;
1209                 case 1:
1210                         if (!tomoyo_read_domain_keeper_policy(head))
1211                                 break;
1212                         head->read_var2 = NULL;
1213                         head->read_step = 2;
1214                 case 2:
1215                         if (!tomoyo_read_globally_readable_policy(head))
1216                                 break;
1217                         head->read_var2 = NULL;
1218                         head->read_step = 3;
1219                 case 3:
1220                         head->read_var2 = NULL;
1221                         head->read_step = 4;
1222                 case 4:
1223                         if (!tomoyo_read_domain_initializer_policy(head))
1224                                 break;
1225                         head->read_var2 = NULL;
1226                         head->read_step = 5;
1227                 case 5:
1228                         if (!tomoyo_read_alias_policy(head))
1229                                 break;
1230                         head->read_var2 = NULL;
1231                         head->read_step = 6;
1232                 case 6:
1233                         if (!tomoyo_read_aggregator_policy(head))
1234                                 break;
1235                         head->read_var2 = NULL;
1236                         head->read_step = 7;
1237                 case 7:
1238                         if (!tomoyo_read_file_pattern(head))
1239                                 break;
1240                         head->read_var2 = NULL;
1241                         head->read_step = 8;
1242                 case 8:
1243                         if (!tomoyo_read_no_rewrite_policy(head))
1244                                 break;
1245                         head->read_var2 = NULL;
1246                         head->read_step = 9;
1247                 case 9:
1248                         if (!tomoyo_read_path_group_policy(head))
1249                                 break;
1250                         head->read_var1 = NULL;
1251                         head->read_var2 = NULL;
1252                         head->read_step = 10;
1253                 case 10:
1254                         if (!tomoyo_read_number_group_policy(head))
1255                                 break;
1256                         head->read_var1 = NULL;
1257                         head->read_var2 = NULL;
1258                         head->read_step = 11;
1259                 case 11:
1260                         head->read_eof = true;
1261                         break;
1262                 }
1263         }
1264 }
1265
1266 /**
1267  * tomoyo_print_header - Get header line of audit log.
1268  *
1269  * @r: Pointer to "struct tomoyo_request_info".
1270  *
1271  * Returns string representation.
1272  *
1273  * This function uses kmalloc(), so caller must kfree() if this function
1274  * didn't return NULL.
1275  */
1276 static char *tomoyo_print_header(struct tomoyo_request_info *r)
1277 {
1278         static const char *tomoyo_mode_4[4] = {
1279                 "disabled", "learning", "permissive", "enforcing"
1280         };
1281         struct timeval tv;
1282         const pid_t gpid = task_pid_nr(current);
1283         static const int tomoyo_buffer_len = 4096;
1284         char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
1285         if (!buffer)
1286                 return NULL;
1287         do_gettimeofday(&tv);
1288         snprintf(buffer, tomoyo_buffer_len - 1,
1289                  "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
1290                  " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
1291                  " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
1292                  tv.tv_sec, r->profile, tomoyo_mode_4[r->mode], gpid,
1293                  (pid_t) sys_getpid(), (pid_t) sys_getppid(),
1294                  current_uid(), current_gid(), current_euid(),
1295                  current_egid(), current_suid(), current_sgid(),
1296                  current_fsuid(), current_fsgid());
1297         return buffer;
1298 }
1299
1300 /**
1301  * tomoyo_init_audit_log - Allocate buffer for audit logs.
1302  *
1303  * @len: Required size.
1304  * @r:   Pointer to "struct tomoyo_request_info".
1305  *
1306  * Returns pointer to allocated memory.
1307  *
1308  * The @len is updated to add the header lines' size on success.
1309  *
1310  * This function uses kzalloc(), so caller must kfree() if this function
1311  * didn't return NULL.
1312  */
1313 static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r)
1314 {
1315         char *buf = NULL;
1316         const char *header;
1317         const char *domainname;
1318         if (!r->domain)
1319                 r->domain = tomoyo_domain();
1320         domainname = r->domain->domainname->name;
1321         header = tomoyo_print_header(r);
1322         if (!header)
1323                 return NULL;
1324         *len += strlen(domainname) + strlen(header) + 10;
1325         buf = kzalloc(*len, GFP_NOFS);
1326         if (buf)
1327                 snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname);
1328         kfree(header);
1329         return buf;
1330 }
1331
1332 /* Wait queue for tomoyo_query_list. */
1333 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1334
1335 /* Lock for manipulating tomoyo_query_list. */
1336 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1337
1338 /* Structure for query. */
1339 struct tomoyo_query_entry {
1340         struct list_head list;
1341         char *query;
1342         int query_len;
1343         unsigned int serial;
1344         int timer;
1345         int answer;
1346 };
1347
1348 /* The list for "struct tomoyo_query_entry". */
1349 static LIST_HEAD(tomoyo_query_list);
1350
1351 /*
1352  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1353  * interface.
1354  */
1355 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1356
1357 /**
1358  * tomoyo_supervisor - Ask for the supervisor's decision.
1359  *
1360  * @r:       Pointer to "struct tomoyo_request_info".
1361  * @fmt:     The printf()'s format string, followed by parameters.
1362  *
1363  * Returns 0 if the supervisor decided to permit the access request which
1364  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1365  * supervisor decided to retry the access request which violated the policy in
1366  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1367  */
1368 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1369 {
1370         va_list args;
1371         int error = -EPERM;
1372         int pos;
1373         int len;
1374         static unsigned int tomoyo_serial;
1375         struct tomoyo_query_entry *tomoyo_query_entry = NULL;
1376         bool quota_exceeded = false;
1377         char *header;
1378         switch (r->mode) {
1379                 char *buffer;
1380         case TOMOYO_CONFIG_LEARNING:
1381                 if (!tomoyo_domain_quota_is_ok(r))
1382                         return 0;
1383                 va_start(args, fmt);
1384                 len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4;
1385                 va_end(args);
1386                 buffer = kmalloc(len, GFP_NOFS);
1387                 if (!buffer)
1388                         return 0;
1389                 va_start(args, fmt);
1390                 vsnprintf(buffer, len - 1, fmt, args);
1391                 va_end(args);
1392                 tomoyo_normalize_line(buffer);
1393                 tomoyo_write_domain_policy2(buffer, r->domain, false);
1394                 kfree(buffer);
1395                 /* fall through */
1396         case TOMOYO_CONFIG_PERMISSIVE:
1397                 return 0;
1398         }
1399         if (!r->domain)
1400                 r->domain = tomoyo_domain();
1401         if (!atomic_read(&tomoyo_query_observers))
1402                 return -EPERM;
1403         va_start(args, fmt);
1404         len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
1405         va_end(args);
1406         header = tomoyo_init_audit_log(&len, r);
1407         if (!header)
1408                 goto out;
1409         tomoyo_query_entry = kzalloc(sizeof(*tomoyo_query_entry), GFP_NOFS);
1410         if (!tomoyo_query_entry)
1411                 goto out;
1412         tomoyo_query_entry->query = kzalloc(len, GFP_NOFS);
1413         if (!tomoyo_query_entry->query)
1414                 goto out;
1415         len = ksize(tomoyo_query_entry->query);
1416         INIT_LIST_HEAD(&tomoyo_query_entry->list);
1417         spin_lock(&tomoyo_query_list_lock);
1418         if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
1419             sizeof(*tomoyo_query_entry) >= tomoyo_quota_for_query) {
1420                 quota_exceeded = true;
1421         } else {
1422                 tomoyo_query_memory_size += len + sizeof(*tomoyo_query_entry);
1423                 tomoyo_query_entry->serial = tomoyo_serial++;
1424         }
1425         spin_unlock(&tomoyo_query_list_lock);
1426         if (quota_exceeded)
1427                 goto out;
1428         pos = snprintf(tomoyo_query_entry->query, len - 1, "Q%u-%hu\n%s",
1429                        tomoyo_query_entry->serial, r->retry, header);
1430         kfree(header);
1431         header = NULL;
1432         va_start(args, fmt);
1433         vsnprintf(tomoyo_query_entry->query + pos, len - 1 - pos, fmt, args);
1434         tomoyo_query_entry->query_len = strlen(tomoyo_query_entry->query) + 1;
1435         va_end(args);
1436         spin_lock(&tomoyo_query_list_lock);
1437         list_add_tail(&tomoyo_query_entry->list, &tomoyo_query_list);
1438         spin_unlock(&tomoyo_query_list_lock);
1439         /* Give 10 seconds for supervisor's opinion. */
1440         for (tomoyo_query_entry->timer = 0;
1441              atomic_read(&tomoyo_query_observers) && tomoyo_query_entry->timer < 100;
1442              tomoyo_query_entry->timer++) {
1443                 wake_up(&tomoyo_query_wait);
1444                 set_current_state(TASK_INTERRUPTIBLE);
1445                 schedule_timeout(HZ / 10);
1446                 if (tomoyo_query_entry->answer)
1447                         break;
1448         }
1449         spin_lock(&tomoyo_query_list_lock);
1450         list_del(&tomoyo_query_entry->list);
1451         tomoyo_query_memory_size -= len + sizeof(*tomoyo_query_entry);
1452         spin_unlock(&tomoyo_query_list_lock);
1453         switch (tomoyo_query_entry->answer) {
1454         case 3: /* Asked to retry by administrator. */
1455                 error = TOMOYO_RETRY_REQUEST;
1456                 r->retry++;
1457                 break;
1458         case 1:
1459                 /* Granted by administrator. */
1460                 error = 0;
1461                 break;
1462         case 0:
1463                 /* Timed out. */
1464                 break;
1465         default:
1466                 /* Rejected by administrator. */
1467                 break;
1468         }
1469  out:
1470         if (tomoyo_query_entry)
1471                 kfree(tomoyo_query_entry->query);
1472         kfree(tomoyo_query_entry);
1473         kfree(header);
1474         return error;
1475 }
1476
1477 /**
1478  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1479  *
1480  * @file: Pointer to "struct file".
1481  * @wait: Pointer to "poll_table".
1482  *
1483  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1484  *
1485  * Waits for access requests which violated policy in enforcing mode.
1486  */
1487 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1488 {
1489         struct list_head *tmp;
1490         bool found = false;
1491         u8 i;
1492         for (i = 0; i < 2; i++) {
1493                 spin_lock(&tomoyo_query_list_lock);
1494                 list_for_each(tmp, &tomoyo_query_list) {
1495                         struct tomoyo_query_entry *ptr
1496                                 = list_entry(tmp, struct tomoyo_query_entry,
1497                                              list);
1498                         if (ptr->answer)
1499                                 continue;
1500                         found = true;
1501                         break;
1502                 }
1503                 spin_unlock(&tomoyo_query_list_lock);
1504                 if (found)
1505                         return POLLIN | POLLRDNORM;
1506                 if (i)
1507                         break;
1508                 poll_wait(file, &tomoyo_query_wait, wait);
1509         }
1510         return 0;
1511 }
1512
1513 /**
1514  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1515  *
1516  * @head: Pointer to "struct tomoyo_io_buffer".
1517  */
1518 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1519 {
1520         struct list_head *tmp;
1521         int pos = 0;
1522         int len = 0;
1523         char *buf;
1524         if (head->read_avail)
1525                 return;
1526         if (head->read_buf) {
1527                 kfree(head->read_buf);
1528                 head->read_buf = NULL;
1529                 head->readbuf_size = 0;
1530         }
1531         spin_lock(&tomoyo_query_list_lock);
1532         list_for_each(tmp, &tomoyo_query_list) {
1533                 struct tomoyo_query_entry *ptr
1534                         = list_entry(tmp, struct tomoyo_query_entry, list);
1535                 if (ptr->answer)
1536                         continue;
1537                 if (pos++ != head->read_step)
1538                         continue;
1539                 len = ptr->query_len;
1540                 break;
1541         }
1542         spin_unlock(&tomoyo_query_list_lock);
1543         if (!len) {
1544                 head->read_step = 0;
1545                 return;
1546         }
1547         buf = kzalloc(len, GFP_NOFS);
1548         if (!buf)
1549                 return;
1550         pos = 0;
1551         spin_lock(&tomoyo_query_list_lock);
1552         list_for_each(tmp, &tomoyo_query_list) {
1553                 struct tomoyo_query_entry *ptr
1554                         = list_entry(tmp, struct tomoyo_query_entry, list);
1555                 if (ptr->answer)
1556                         continue;
1557                 if (pos++ != head->read_step)
1558                         continue;
1559                 /*
1560                  * Some query can be skipped because tomoyo_query_list
1561                  * can change, but I don't care.
1562                  */
1563                 if (len == ptr->query_len)
1564                         memmove(buf, ptr->query, len);
1565                 break;
1566         }
1567         spin_unlock(&tomoyo_query_list_lock);
1568         if (buf[0]) {
1569                 head->read_avail = len;
1570                 head->readbuf_size = head->read_avail;
1571                 head->read_buf = buf;
1572                 head->read_step++;
1573         } else {
1574                 kfree(buf);
1575         }
1576 }
1577
1578 /**
1579  * tomoyo_write_answer - Write the supervisor's decision.
1580  *
1581  * @head: Pointer to "struct tomoyo_io_buffer".
1582  *
1583  * Returns 0 on success, -EINVAL otherwise.
1584  */
1585 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1586 {
1587         char *data = head->write_buf;
1588         struct list_head *tmp;
1589         unsigned int serial;
1590         unsigned int answer;
1591         spin_lock(&tomoyo_query_list_lock);
1592         list_for_each(tmp, &tomoyo_query_list) {
1593                 struct tomoyo_query_entry *ptr
1594                         = list_entry(tmp, struct tomoyo_query_entry, list);
1595                 ptr->timer = 0;
1596         }
1597         spin_unlock(&tomoyo_query_list_lock);
1598         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1599                 return -EINVAL;
1600         spin_lock(&tomoyo_query_list_lock);
1601         list_for_each(tmp, &tomoyo_query_list) {
1602                 struct tomoyo_query_entry *ptr
1603                         = list_entry(tmp, struct tomoyo_query_entry, list);
1604                 if (ptr->serial != serial)
1605                         continue;
1606                 if (!ptr->answer)
1607                         ptr->answer = answer;
1608                 break;
1609         }
1610         spin_unlock(&tomoyo_query_list_lock);
1611         return 0;
1612 }
1613
1614 /**
1615  * tomoyo_read_version: Get version.
1616  *
1617  * @head: Pointer to "struct tomoyo_io_buffer".
1618  *
1619  * Returns version information.
1620  */
1621 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
1622 {
1623         if (!head->read_eof) {
1624                 tomoyo_io_printf(head, "2.3.0-pre");
1625                 head->read_eof = true;
1626         }
1627 }
1628
1629 /**
1630  * tomoyo_read_self_domain - Get the current process's domainname.
1631  *
1632  * @head: Pointer to "struct tomoyo_io_buffer".
1633  *
1634  * Returns the current process's domainname.
1635  */
1636 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1637 {
1638         if (!head->read_eof) {
1639                 /*
1640                  * tomoyo_domain()->domainname != NULL
1641                  * because every process belongs to a domain and
1642                  * the domain's name cannot be NULL.
1643                  */
1644                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1645                 head->read_eof = true;
1646         }
1647 }
1648
1649 /**
1650  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1651  *
1652  * @type: Type of interface.
1653  * @file: Pointer to "struct file".
1654  *
1655  * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
1656  *
1657  * Caller acquires tomoyo_read_lock().
1658  */
1659 int tomoyo_open_control(const u8 type, struct file *file)
1660 {
1661         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1662
1663         if (!head)
1664                 return -ENOMEM;
1665         mutex_init(&head->io_sem);
1666         head->type = type;
1667         switch (type) {
1668         case TOMOYO_DOMAINPOLICY:
1669                 /* /sys/kernel/security/tomoyo/domain_policy */
1670                 head->write = tomoyo_write_domain_policy;
1671                 head->read = tomoyo_read_domain_policy;
1672                 break;
1673         case TOMOYO_EXCEPTIONPOLICY:
1674                 /* /sys/kernel/security/tomoyo/exception_policy */
1675                 head->write = tomoyo_write_exception_policy;
1676                 head->read = tomoyo_read_exception_policy;
1677                 break;
1678         case TOMOYO_SELFDOMAIN:
1679                 /* /sys/kernel/security/tomoyo/self_domain */
1680                 head->read = tomoyo_read_self_domain;
1681                 break;
1682         case TOMOYO_DOMAIN_STATUS:
1683                 /* /sys/kernel/security/tomoyo/.domain_status */
1684                 head->write = tomoyo_write_domain_profile;
1685                 head->read = tomoyo_read_domain_profile;
1686                 break;
1687         case TOMOYO_PROCESS_STATUS:
1688                 /* /sys/kernel/security/tomoyo/.process_status */
1689                 head->write = tomoyo_write_pid;
1690                 head->read = tomoyo_read_pid;
1691                 break;
1692         case TOMOYO_VERSION:
1693                 /* /sys/kernel/security/tomoyo/version */
1694                 head->read = tomoyo_read_version;
1695                 head->readbuf_size = 128;
1696                 break;
1697         case TOMOYO_MEMINFO:
1698                 /* /sys/kernel/security/tomoyo/meminfo */
1699                 head->write = tomoyo_write_memory_quota;
1700                 head->read = tomoyo_read_memory_counter;
1701                 head->readbuf_size = 512;
1702                 break;
1703         case TOMOYO_PROFILE:
1704                 /* /sys/kernel/security/tomoyo/profile */
1705                 head->write = tomoyo_write_profile;
1706                 head->read = tomoyo_read_profile;
1707                 break;
1708         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1709                 head->poll = tomoyo_poll_query;
1710                 head->write = tomoyo_write_answer;
1711                 head->read = tomoyo_read_query;
1712                 break;
1713         case TOMOYO_MANAGER:
1714                 /* /sys/kernel/security/tomoyo/manager */
1715                 head->write = tomoyo_write_manager_policy;
1716                 head->read = tomoyo_read_manager_policy;
1717                 break;
1718         }
1719         if (!(file->f_mode & FMODE_READ)) {
1720                 /*
1721                  * No need to allocate read_buf since it is not opened
1722                  * for reading.
1723                  */
1724                 head->read = NULL;
1725                 head->poll = NULL;
1726         } else if (!head->poll) {
1727                 /* Don't allocate read_buf for poll() access. */
1728                 if (!head->readbuf_size)
1729                         head->readbuf_size = 4096 * 2;
1730                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1731                 if (!head->read_buf) {
1732                         kfree(head);
1733                         return -ENOMEM;
1734                 }
1735         }
1736         if (!(file->f_mode & FMODE_WRITE)) {
1737                 /*
1738                  * No need to allocate write_buf since it is not opened
1739                  * for writing.
1740                  */
1741                 head->write = NULL;
1742         } else if (head->write) {
1743                 head->writebuf_size = 4096 * 2;
1744                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1745                 if (!head->write_buf) {
1746                         kfree(head->read_buf);
1747                         kfree(head);
1748                         return -ENOMEM;
1749                 }
1750         }
1751         if (type != TOMOYO_QUERY)
1752                 head->reader_idx = tomoyo_read_lock();
1753         file->private_data = head;
1754         /*
1755          * Call the handler now if the file is
1756          * /sys/kernel/security/tomoyo/self_domain
1757          * so that the user can use
1758          * cat < /sys/kernel/security/tomoyo/self_domain"
1759          * to know the current process's domainname.
1760          */
1761         if (type == TOMOYO_SELFDOMAIN)
1762                 tomoyo_read_control(file, NULL, 0);
1763         /*
1764          * If the file is /sys/kernel/security/tomoyo/query , increment the
1765          * observer counter.
1766          * The obserber counter is used by tomoyo_supervisor() to see if
1767          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1768          */
1769         else if (type == TOMOYO_QUERY)
1770                 atomic_inc(&tomoyo_query_observers);
1771         return 0;
1772 }
1773
1774 /**
1775  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1776  *
1777  * @file: Pointer to "struct file".
1778  * @wait: Pointer to "poll_table".
1779  *
1780  * Waits for read readiness.
1781  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
1782  */
1783 int tomoyo_poll_control(struct file *file, poll_table *wait)
1784 {
1785         struct tomoyo_io_buffer *head = file->private_data;
1786         if (!head->poll)
1787                 return -ENOSYS;
1788         return head->poll(file, wait);
1789 }
1790
1791 /**
1792  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
1793  *
1794  * @file:       Pointer to "struct file".
1795  * @buffer:     Poiner to buffer to write to.
1796  * @buffer_len: Size of @buffer.
1797  *
1798  * Returns bytes read on success, negative value otherwise.
1799  *
1800  * Caller holds tomoyo_read_lock().
1801  */
1802 int tomoyo_read_control(struct file *file, char __user *buffer,
1803                         const int buffer_len)
1804 {
1805         int len = 0;
1806         struct tomoyo_io_buffer *head = file->private_data;
1807         char *cp;
1808
1809         if (!head->read)
1810                 return -ENOSYS;
1811         if (mutex_lock_interruptible(&head->io_sem))
1812                 return -EINTR;
1813         /* Call the policy handler. */
1814         head->read(head);
1815         if (len < 0)
1816                 goto out;
1817         /* Write to buffer. */
1818         len = head->read_avail;
1819         if (len > buffer_len)
1820                 len = buffer_len;
1821         if (!len)
1822                 goto out;
1823         /* head->read_buf changes by some functions. */
1824         cp = head->read_buf;
1825         if (copy_to_user(buffer, cp, len)) {
1826                 len = -EFAULT;
1827                 goto out;
1828         }
1829         head->read_avail -= len;
1830         memmove(cp, cp + len, head->read_avail);
1831  out:
1832         mutex_unlock(&head->io_sem);
1833         return len;
1834 }
1835
1836 /**
1837  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
1838  *
1839  * @file:       Pointer to "struct file".
1840  * @buffer:     Pointer to buffer to read from.
1841  * @buffer_len: Size of @buffer.
1842  *
1843  * Returns @buffer_len on success, negative value otherwise.
1844  *
1845  * Caller holds tomoyo_read_lock().
1846  */
1847 int tomoyo_write_control(struct file *file, const char __user *buffer,
1848                          const int buffer_len)
1849 {
1850         struct tomoyo_io_buffer *head = file->private_data;
1851         int error = buffer_len;
1852         int avail_len = buffer_len;
1853         char *cp0 = head->write_buf;
1854
1855         if (!head->write)
1856                 return -ENOSYS;
1857         if (!access_ok(VERIFY_READ, buffer, buffer_len))
1858                 return -EFAULT;
1859         /* Don't allow updating policies by non manager programs. */
1860         if (head->write != tomoyo_write_pid &&
1861             head->write != tomoyo_write_domain_policy &&
1862             !tomoyo_policy_manager())
1863                 return -EPERM;
1864         if (mutex_lock_interruptible(&head->io_sem))
1865                 return -EINTR;
1866         /* Read a line and dispatch it to the policy handler. */
1867         while (avail_len > 0) {
1868                 char c;
1869                 if (head->write_avail >= head->writebuf_size - 1) {
1870                         error = -ENOMEM;
1871                         break;
1872                 } else if (get_user(c, buffer)) {
1873                         error = -EFAULT;
1874                         break;
1875                 }
1876                 buffer++;
1877                 avail_len--;
1878                 cp0[head->write_avail++] = c;
1879                 if (c != '\n')
1880                         continue;
1881                 cp0[head->write_avail - 1] = '\0';
1882                 head->write_avail = 0;
1883                 tomoyo_normalize_line(cp0);
1884                 head->write(head);
1885         }
1886         mutex_unlock(&head->io_sem);
1887         return error;
1888 }
1889
1890 /**
1891  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
1892  *
1893  * @file: Pointer to "struct file".
1894  *
1895  * Releases memory and returns 0.
1896  *
1897  * Caller looses tomoyo_read_lock().
1898  */
1899 int tomoyo_close_control(struct file *file)
1900 {
1901         struct tomoyo_io_buffer *head = file->private_data;
1902         const bool is_write = !!head->write_buf;
1903
1904         /*
1905          * If the file is /sys/kernel/security/tomoyo/query , decrement the
1906          * observer counter.
1907          */
1908         if (head->type == TOMOYO_QUERY)
1909                 atomic_dec(&tomoyo_query_observers);
1910         else
1911                 tomoyo_read_unlock(head->reader_idx);
1912         /* Release memory used for policy I/O. */
1913         kfree(head->read_buf);
1914         head->read_buf = NULL;
1915         kfree(head->write_buf);
1916         head->write_buf = NULL;
1917         kfree(head);
1918         head = NULL;
1919         file->private_data = NULL;
1920         if (is_write)
1921                 tomoyo_run_gc();
1922         return 0;
1923 }
1924
1925 /**
1926  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
1927  */
1928 void tomoyo_check_profile(void)
1929 {
1930         struct tomoyo_domain_info *domain;
1931         const int idx = tomoyo_read_lock();
1932         tomoyo_policy_loaded = true;
1933         /* Check all profiles currently assigned to domains are defined. */
1934         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
1935                 const u8 profile = domain->profile;
1936                 if (tomoyo_profile_ptr[profile])
1937                         continue;
1938                 panic("Profile %u (used by '%s') not defined.\n",
1939                       profile, domain->domainname->name);
1940         }
1941         tomoyo_read_unlock(idx);
1942         if (tomoyo_profile_version != 20090903)
1943                 panic("Profile version %u is not supported.\n",
1944                       tomoyo_profile_version);
1945         printk(KERN_INFO "TOMOYO: 2.3.0-pre   2010/06/03\n");
1946         printk(KERN_INFO "Mandatory Access Control activated.\n");
1947 }