6402183e2a6b15e0f0386036bd95a11078a2137d
[linux-2.6.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 /* String table for operation mode. */
15 const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE] = {
16         [TOMOYO_CONFIG_DISABLED]   = "disabled",
17         [TOMOYO_CONFIG_LEARNING]   = "learning",
18         [TOMOYO_CONFIG_PERMISSIVE] = "permissive",
19         [TOMOYO_CONFIG_ENFORCING]  = "enforcing"
20 };
21
22 /* String table for /sys/kernel/security/tomoyo/profile */
23 const char * const tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
24                                        + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
25         [TOMOYO_MAC_FILE_EXECUTE]    = "execute",
26         [TOMOYO_MAC_FILE_OPEN]       = "open",
27         [TOMOYO_MAC_FILE_CREATE]     = "create",
28         [TOMOYO_MAC_FILE_UNLINK]     = "unlink",
29         [TOMOYO_MAC_FILE_GETATTR]    = "getattr",
30         [TOMOYO_MAC_FILE_MKDIR]      = "mkdir",
31         [TOMOYO_MAC_FILE_RMDIR]      = "rmdir",
32         [TOMOYO_MAC_FILE_MKFIFO]     = "mkfifo",
33         [TOMOYO_MAC_FILE_MKSOCK]     = "mksock",
34         [TOMOYO_MAC_FILE_TRUNCATE]   = "truncate",
35         [TOMOYO_MAC_FILE_SYMLINK]    = "symlink",
36         [TOMOYO_MAC_FILE_MKBLOCK]    = "mkblock",
37         [TOMOYO_MAC_FILE_MKCHAR]     = "mkchar",
38         [TOMOYO_MAC_FILE_LINK]       = "link",
39         [TOMOYO_MAC_FILE_RENAME]     = "rename",
40         [TOMOYO_MAC_FILE_CHMOD]      = "chmod",
41         [TOMOYO_MAC_FILE_CHOWN]      = "chown",
42         [TOMOYO_MAC_FILE_CHGRP]      = "chgrp",
43         [TOMOYO_MAC_FILE_IOCTL]      = "ioctl",
44         [TOMOYO_MAC_FILE_CHROOT]     = "chroot",
45         [TOMOYO_MAC_FILE_MOUNT]      = "mount",
46         [TOMOYO_MAC_FILE_UMOUNT]     = "unmount",
47         [TOMOYO_MAC_FILE_PIVOT_ROOT] = "pivot_root",
48         [TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
49 };
50
51 /* String table for PREFERENCE keyword. */
52 static const char * const tomoyo_pref_keywords[TOMOYO_MAX_PREF] = {
53         [TOMOYO_PREF_MAX_AUDIT_LOG]      = "max_audit_log",
54         [TOMOYO_PREF_MAX_LEARNING_ENTRY] = "max_learning_entry",
55 };
56
57 /* String table for path operation. */
58 const char * const tomoyo_path_keyword[TOMOYO_MAX_PATH_OPERATION] = {
59         [TOMOYO_TYPE_EXECUTE]    = "execute",
60         [TOMOYO_TYPE_READ]       = "read",
61         [TOMOYO_TYPE_WRITE]      = "write",
62         [TOMOYO_TYPE_APPEND]     = "append",
63         [TOMOYO_TYPE_UNLINK]     = "unlink",
64         [TOMOYO_TYPE_GETATTR]    = "getattr",
65         [TOMOYO_TYPE_RMDIR]      = "rmdir",
66         [TOMOYO_TYPE_TRUNCATE]   = "truncate",
67         [TOMOYO_TYPE_SYMLINK]    = "symlink",
68         [TOMOYO_TYPE_CHROOT]     = "chroot",
69         [TOMOYO_TYPE_UMOUNT]     = "unmount",
70 };
71
72 /* String table for categories. */
73 static const char * const tomoyo_category_keywords
74 [TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
75         [TOMOYO_MAC_CATEGORY_FILE]       = "file",
76 };
77
78 /* Permit policy management by non-root user? */
79 static bool tomoyo_manage_by_non_root;
80
81 /* Utility functions. */
82
83 /**
84  * tomoyo_yesno - Return "yes" or "no".
85  *
86  * @value: Bool value.
87  */
88 const char *tomoyo_yesno(const unsigned int value)
89 {
90         return value ? "yes" : "no";
91 }
92
93 /**
94  * tomoyo_addprintf - strncat()-like-snprintf().
95  *
96  * @buffer: Buffer to write to. Must be '\0'-terminated.
97  * @len:    Size of @buffer.
98  * @fmt:    The printf()'s format string, followed by parameters.
99  *
100  * Returns nothing.
101  */
102 static void tomoyo_addprintf(char *buffer, int len, const char *fmt, ...)
103 {
104         va_list args;
105         const int pos = strlen(buffer);
106         va_start(args, fmt);
107         vsnprintf(buffer + pos, len - pos - 1, fmt, args);
108         va_end(args);
109 }
110
111 /**
112  * tomoyo_flush - Flush queued string to userspace's buffer.
113  *
114  * @head:   Pointer to "struct tomoyo_io_buffer".
115  *
116  * Returns true if all data was flushed, false otherwise.
117  */
118 static bool tomoyo_flush(struct tomoyo_io_buffer *head)
119 {
120         while (head->r.w_pos) {
121                 const char *w = head->r.w[0];
122                 size_t len = strlen(w);
123                 if (len) {
124                         if (len > head->read_user_buf_avail)
125                                 len = head->read_user_buf_avail;
126                         if (!len)
127                                 return false;
128                         if (copy_to_user(head->read_user_buf, w, len))
129                                 return false;
130                         head->read_user_buf_avail -= len;
131                         head->read_user_buf += len;
132                         w += len;
133                 }
134                 head->r.w[0] = w;
135                 if (*w)
136                         return false;
137                 /* Add '\0' for audit logs and query. */
138                 if (head->poll) {
139                         if (!head->read_user_buf_avail ||
140                             copy_to_user(head->read_user_buf, "", 1))
141                                 return false;
142                         head->read_user_buf_avail--;
143                         head->read_user_buf++;
144                 }
145                 head->r.w_pos--;
146                 for (len = 0; len < head->r.w_pos; len++)
147                         head->r.w[len] = head->r.w[len + 1];
148         }
149         head->r.avail = 0;
150         return true;
151 }
152
153 /**
154  * tomoyo_set_string - Queue string to "struct tomoyo_io_buffer" structure.
155  *
156  * @head:   Pointer to "struct tomoyo_io_buffer".
157  * @string: String to print.
158  *
159  * Note that @string has to be kept valid until @head is kfree()d.
160  * This means that char[] allocated on stack memory cannot be passed to
161  * this function. Use tomoyo_io_printf() for char[] allocated on stack memory.
162  */
163 static void tomoyo_set_string(struct tomoyo_io_buffer *head, const char *string)
164 {
165         if (head->r.w_pos < TOMOYO_MAX_IO_READ_QUEUE) {
166                 head->r.w[head->r.w_pos++] = string;
167                 tomoyo_flush(head);
168         } else
169                 WARN_ON(1);
170 }
171
172 /**
173  * tomoyo_io_printf - printf() to "struct tomoyo_io_buffer" structure.
174  *
175  * @head: Pointer to "struct tomoyo_io_buffer".
176  * @fmt:  The printf()'s format string, followed by parameters.
177  */
178 void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
179 {
180         va_list args;
181         size_t len;
182         size_t pos = head->r.avail;
183         int size = head->readbuf_size - pos;
184         if (size <= 0)
185                 return;
186         va_start(args, fmt);
187         len = vsnprintf(head->read_buf + pos, size, fmt, args) + 1;
188         va_end(args);
189         if (pos + len >= head->readbuf_size) {
190                 WARN_ON(1);
191                 return;
192         }
193         head->r.avail += len;
194         tomoyo_set_string(head, head->read_buf + pos);
195 }
196
197 /**
198  * tomoyo_set_space - Put a space to "struct tomoyo_io_buffer" structure.
199  *
200  * @head: Pointer to "struct tomoyo_io_buffer".
201  *
202  * Returns nothing.
203  */
204 static void tomoyo_set_space(struct tomoyo_io_buffer *head)
205 {
206         tomoyo_set_string(head, " ");
207 }
208
209 /**
210  * tomoyo_set_lf - Put a line feed to "struct tomoyo_io_buffer" structure.
211  *
212  * @head: Pointer to "struct tomoyo_io_buffer".
213  *
214  * Returns nothing.
215  */
216 static bool tomoyo_set_lf(struct tomoyo_io_buffer *head)
217 {
218         tomoyo_set_string(head, "\n");
219         return !head->r.w_pos;
220 }
221
222 /**
223  * tomoyo_set_slash - Put a shash to "struct tomoyo_io_buffer" structure.
224  *
225  * @head: Pointer to "struct tomoyo_io_buffer".
226  *
227  * Returns nothing.
228  */
229 static void tomoyo_set_slash(struct tomoyo_io_buffer *head)
230 {
231         tomoyo_set_string(head, "/");
232 }
233
234 /* List of namespaces. */
235 LIST_HEAD(tomoyo_namespace_list);
236 /* True if namespace other than tomoyo_kernel_namespace is defined. */
237 static bool tomoyo_namespace_enabled;
238
239 /**
240  * tomoyo_init_policy_namespace - Initialize namespace.
241  *
242  * @ns: Pointer to "struct tomoyo_policy_namespace".
243  *
244  * Returns nothing.
245  */
246 void tomoyo_init_policy_namespace(struct tomoyo_policy_namespace *ns)
247 {
248         unsigned int idx;
249         for (idx = 0; idx < TOMOYO_MAX_ACL_GROUPS; idx++)
250                 INIT_LIST_HEAD(&ns->acl_group[idx]);
251         for (idx = 0; idx < TOMOYO_MAX_GROUP; idx++)
252                 INIT_LIST_HEAD(&ns->group_list[idx]);
253         for (idx = 0; idx < TOMOYO_MAX_POLICY; idx++)
254                 INIT_LIST_HEAD(&ns->policy_list[idx]);
255         ns->profile_version = 20100903;
256         tomoyo_namespace_enabled = !list_empty(&tomoyo_namespace_list);
257         list_add_tail_rcu(&ns->namespace_list, &tomoyo_namespace_list);
258 }
259
260 /**
261  * tomoyo_print_namespace - Print namespace header.
262  *
263  * @head: Pointer to "struct tomoyo_io_buffer".
264  *
265  * Returns nothing.
266  */
267 static void tomoyo_print_namespace(struct tomoyo_io_buffer *head)
268 {
269         if (!tomoyo_namespace_enabled)
270                 return;
271         tomoyo_set_string(head,
272                           container_of(head->r.ns,
273                                        struct tomoyo_policy_namespace,
274                                        namespace_list)->name);
275         tomoyo_set_space(head);
276 }
277
278 /**
279  * tomoyo_print_name_union - Print a tomoyo_name_union.
280  *
281  * @head: Pointer to "struct tomoyo_io_buffer".
282  * @ptr:  Pointer to "struct tomoyo_name_union".
283  */
284 static void tomoyo_print_name_union(struct tomoyo_io_buffer *head,
285                                     const struct tomoyo_name_union *ptr)
286 {
287         tomoyo_set_space(head);
288         if (ptr->group) {
289                 tomoyo_set_string(head, "@");
290                 tomoyo_set_string(head, ptr->group->group_name->name);
291         } else {
292                 tomoyo_set_string(head, ptr->filename->name);
293         }
294 }
295
296 /**
297  * tomoyo_print_number_union - Print a tomoyo_number_union.
298  *
299  * @head:       Pointer to "struct tomoyo_io_buffer".
300  * @ptr:        Pointer to "struct tomoyo_number_union".
301  */
302 static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
303                                       const struct tomoyo_number_union *ptr)
304 {
305         tomoyo_set_space(head);
306         if (ptr->group) {
307                 tomoyo_set_string(head, "@");
308                 tomoyo_set_string(head, ptr->group->group_name->name);
309         } else {
310                 int i;
311                 unsigned long min = ptr->values[0];
312                 const unsigned long max = ptr->values[1];
313                 u8 min_type = ptr->value_type[0];
314                 const u8 max_type = ptr->value_type[1];
315                 char buffer[128];
316                 buffer[0] = '\0';
317                 for (i = 0; i < 2; i++) {
318                         switch (min_type) {
319                         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
320                                 tomoyo_addprintf(buffer, sizeof(buffer),
321                                                  "0x%lX", min);
322                                 break;
323                         case TOMOYO_VALUE_TYPE_OCTAL:
324                                 tomoyo_addprintf(buffer, sizeof(buffer),
325                                                  "0%lo", min);
326                                 break;
327                         default:
328                                 tomoyo_addprintf(buffer, sizeof(buffer),
329                                                  "%lu", min);
330                                 break;
331                         }
332                         if (min == max && min_type == max_type)
333                                 break;
334                         tomoyo_addprintf(buffer, sizeof(buffer), "-");
335                         min_type = max_type;
336                         min = max;
337                 }
338                 tomoyo_io_printf(head, "%s", buffer);
339         }
340 }
341
342 /**
343  * tomoyo_assign_profile - Create a new profile.
344  *
345  * @ns:      Pointer to "struct tomoyo_policy_namespace".
346  * @profile: Profile number to create.
347  *
348  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
349  */
350 static struct tomoyo_profile *tomoyo_assign_profile
351 (struct tomoyo_policy_namespace *ns, const unsigned int profile)
352 {
353         struct tomoyo_profile *ptr;
354         struct tomoyo_profile *entry;
355         if (profile >= TOMOYO_MAX_PROFILES)
356                 return NULL;
357         ptr = ns->profile_ptr[profile];
358         if (ptr)
359                 return ptr;
360         entry = kzalloc(sizeof(*entry), GFP_NOFS);
361         if (mutex_lock_interruptible(&tomoyo_policy_lock))
362                 goto out;
363         ptr = ns->profile_ptr[profile];
364         if (!ptr && tomoyo_memory_ok(entry)) {
365                 ptr = entry;
366                 ptr->default_config = TOMOYO_CONFIG_DISABLED |
367                         TOMOYO_CONFIG_WANT_GRANT_LOG |
368                         TOMOYO_CONFIG_WANT_REJECT_LOG;
369                 memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
370                        sizeof(ptr->config));
371                 ptr->pref[TOMOYO_PREF_MAX_AUDIT_LOG] = 1024;
372                 ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] = 2048;
373                 mb(); /* Avoid out-of-order execution. */
374                 ns->profile_ptr[profile] = ptr;
375                 entry = NULL;
376         }
377         mutex_unlock(&tomoyo_policy_lock);
378  out:
379         kfree(entry);
380         return ptr;
381 }
382
383 /**
384  * tomoyo_profile - Find a profile.
385  *
386  * @ns:      Pointer to "struct tomoyo_policy_namespace".
387  * @profile: Profile number to find.
388  *
389  * Returns pointer to "struct tomoyo_profile".
390  */
391 struct tomoyo_profile *tomoyo_profile(const struct tomoyo_policy_namespace *ns,
392                                       const u8 profile)
393 {
394         static struct tomoyo_profile tomoyo_null_profile;
395         struct tomoyo_profile *ptr = ns->profile_ptr[profile];
396         if (!ptr)
397                 ptr = &tomoyo_null_profile;
398         return ptr;
399 }
400
401 /**
402  * tomoyo_find_yesno - Find values for specified keyword.
403  *
404  * @string: String to check.
405  * @find:   Name of keyword.
406  *
407  * Returns 1 if "@find=yes" was found, 0 if "@find=no" was found, -1 otherwise.
408  */
409 static s8 tomoyo_find_yesno(const char *string, const char *find)
410 {
411         const char *cp = strstr(string, find);
412         if (cp) {
413                 cp += strlen(find);
414                 if (!strncmp(cp, "=yes", 4))
415                         return 1;
416                 else if (!strncmp(cp, "=no", 3))
417                         return 0;
418         }
419         return -1;
420 }
421
422 /**
423  * tomoyo_set_uint - Set value for specified preference.
424  *
425  * @i:      Pointer to "unsigned int".
426  * @string: String to check.
427  * @find:   Name of keyword.
428  *
429  * Returns nothing.
430  */
431 static void tomoyo_set_uint(unsigned int *i, const char *string,
432                             const char *find)
433 {
434         const char *cp = strstr(string, find);
435         if (cp)
436                 sscanf(cp + strlen(find), "=%u", i);
437 }
438
439 /**
440  * tomoyo_set_mode - Set mode for specified profile.
441  *
442  * @name:    Name of functionality.
443  * @value:   Mode for @name.
444  * @profile: Pointer to "struct tomoyo_profile".
445  *
446  * Returns 0 on success, negative value otherwise.
447  */
448 static int tomoyo_set_mode(char *name, const char *value,
449                            struct tomoyo_profile *profile)
450 {
451         u8 i;
452         u8 config;
453         if (!strcmp(name, "CONFIG")) {
454                 i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
455                 config = profile->default_config;
456         } else if (tomoyo_str_starts(&name, "CONFIG::")) {
457                 config = 0;
458                 for (i = 0; i < TOMOYO_MAX_MAC_INDEX
459                              + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
460                         int len = 0;
461                         if (i < TOMOYO_MAX_MAC_INDEX) {
462                                 const u8 c = tomoyo_index2category[i];
463                                 const char *category =
464                                         tomoyo_category_keywords[c];
465                                 len = strlen(category);
466                                 if (strncmp(name, category, len) ||
467                                     name[len++] != ':' || name[len++] != ':')
468                                         continue;
469                         }
470                         if (strcmp(name + len, tomoyo_mac_keywords[i]))
471                                 continue;
472                         config = profile->config[i];
473                         break;
474                 }
475                 if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
476                         return -EINVAL;
477         } else {
478                 return -EINVAL;
479         }
480         if (strstr(value, "use_default")) {
481                 config = TOMOYO_CONFIG_USE_DEFAULT;
482         } else {
483                 u8 mode;
484                 for (mode = 0; mode < 4; mode++)
485                         if (strstr(value, tomoyo_mode[mode]))
486                                 /*
487                                  * Update lower 3 bits in order to distinguish
488                                  * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
489                                  */
490                                 config = (config & ~7) | mode;
491                 if (config != TOMOYO_CONFIG_USE_DEFAULT) {
492                         switch (tomoyo_find_yesno(value, "grant_log")) {
493                         case 1:
494                                 config |= TOMOYO_CONFIG_WANT_GRANT_LOG;
495                                 break;
496                         case 0:
497                                 config &= ~TOMOYO_CONFIG_WANT_GRANT_LOG;
498                                 break;
499                         }
500                         switch (tomoyo_find_yesno(value, "reject_log")) {
501                         case 1:
502                                 config |= TOMOYO_CONFIG_WANT_REJECT_LOG;
503                                 break;
504                         case 0:
505                                 config &= ~TOMOYO_CONFIG_WANT_REJECT_LOG;
506                                 break;
507                         }
508                 }
509         }
510         if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
511                 profile->config[i] = config;
512         else if (config != TOMOYO_CONFIG_USE_DEFAULT)
513                 profile->default_config = config;
514         return 0;
515 }
516
517 /**
518  * tomoyo_write_profile - Write profile table.
519  *
520  * @head: Pointer to "struct tomoyo_io_buffer".
521  *
522  * Returns 0 on success, negative value otherwise.
523  */
524 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
525 {
526         char *data = head->write_buf;
527         unsigned int i;
528         char *cp;
529         struct tomoyo_profile *profile;
530         if (sscanf(data, "PROFILE_VERSION=%u", &head->w.ns->profile_version)
531             == 1)
532                 return 0;
533         i = simple_strtoul(data, &cp, 10);
534         if (*cp != '-')
535                 return -EINVAL;
536         data = cp + 1;
537         profile = tomoyo_assign_profile(head->w.ns, i);
538         if (!profile)
539                 return -EINVAL;
540         cp = strchr(data, '=');
541         if (!cp)
542                 return -EINVAL;
543         *cp++ = '\0';
544         if (!strcmp(data, "COMMENT")) {
545                 static DEFINE_SPINLOCK(lock);
546                 const struct tomoyo_path_info *new_comment
547                         = tomoyo_get_name(cp);
548                 const struct tomoyo_path_info *old_comment;
549                 if (!new_comment)
550                         return -ENOMEM;
551                 spin_lock(&lock);
552                 old_comment = profile->comment;
553                 profile->comment = new_comment;
554                 spin_unlock(&lock);
555                 tomoyo_put_name(old_comment);
556                 return 0;
557         }
558         if (!strcmp(data, "PREFERENCE")) {
559                 for (i = 0; i < TOMOYO_MAX_PREF; i++)
560                         tomoyo_set_uint(&profile->pref[i], cp,
561                                         tomoyo_pref_keywords[i]);
562                 return 0;
563         }
564         return tomoyo_set_mode(data, cp, profile);
565 }
566
567 /**
568  * tomoyo_print_config - Print mode for specified functionality.
569  *
570  * @head:   Pointer to "struct tomoyo_io_buffer".
571  * @config: Mode for that functionality.
572  *
573  * Returns nothing.
574  *
575  * Caller prints functionality's name.
576  */
577 static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
578 {
579         tomoyo_io_printf(head, "={ mode=%s grant_log=%s reject_log=%s }\n",
580                          tomoyo_mode[config & 3],
581                          tomoyo_yesno(config & TOMOYO_CONFIG_WANT_GRANT_LOG),
582                          tomoyo_yesno(config & TOMOYO_CONFIG_WANT_REJECT_LOG));
583 }
584
585 /**
586  * tomoyo_read_profile - Read profile table.
587  *
588  * @head: Pointer to "struct tomoyo_io_buffer".
589  *
590  * Returns nothing.
591  */
592 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
593 {
594         u8 index;
595         struct tomoyo_policy_namespace *ns =
596                 container_of(head->r.ns, typeof(*ns), namespace_list);
597         const struct tomoyo_profile *profile;
598         if (head->r.eof)
599                 return;
600  next:
601         index = head->r.index;
602         profile = ns->profile_ptr[index];
603         switch (head->r.step) {
604         case 0:
605                 tomoyo_print_namespace(head);
606                 tomoyo_io_printf(head, "PROFILE_VERSION=%u\n",
607                                  ns->profile_version);
608                 head->r.step++;
609                 break;
610         case 1:
611                 for ( ; head->r.index < TOMOYO_MAX_PROFILES;
612                       head->r.index++)
613                         if (ns->profile_ptr[head->r.index])
614                                 break;
615                 if (head->r.index == TOMOYO_MAX_PROFILES)
616                         return;
617                 head->r.step++;
618                 break;
619         case 2:
620                 {
621                         u8 i;
622                         const struct tomoyo_path_info *comment =
623                                 profile->comment;
624                         tomoyo_print_namespace(head);
625                         tomoyo_io_printf(head, "%u-COMMENT=", index);
626                         tomoyo_set_string(head, comment ? comment->name : "");
627                         tomoyo_set_lf(head);
628                         tomoyo_io_printf(head, "%u-PREFERENCE={ ", index);
629                         for (i = 0; i < TOMOYO_MAX_PREF; i++)
630                                 tomoyo_io_printf(head, "%s=%u ",
631                                                  tomoyo_pref_keywords[i],
632                                                  profile->pref[i]);
633                         tomoyo_set_string(head, "}\n");
634                         head->r.step++;
635                 }
636                 break;
637         case 3:
638                 {
639                         tomoyo_print_namespace(head);
640                         tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
641                         tomoyo_print_config(head, profile->default_config);
642                         head->r.bit = 0;
643                         head->r.step++;
644                 }
645                 break;
646         case 4:
647                 for ( ; head->r.bit < TOMOYO_MAX_MAC_INDEX
648                               + TOMOYO_MAX_MAC_CATEGORY_INDEX; head->r.bit++) {
649                         const u8 i = head->r.bit;
650                         const u8 config = profile->config[i];
651                         if (config == TOMOYO_CONFIG_USE_DEFAULT)
652                                 continue;
653                         tomoyo_print_namespace(head);
654                         if (i < TOMOYO_MAX_MAC_INDEX)
655                                 tomoyo_io_printf(head, "%u-CONFIG::%s::%s",
656                                                  index,
657                                                  tomoyo_category_keywords
658                                                  [tomoyo_index2category[i]],
659                                                  tomoyo_mac_keywords[i]);
660                         else
661                                 tomoyo_io_printf(head, "%u-CONFIG::%s", index,
662                                                  tomoyo_mac_keywords[i]);
663                         tomoyo_print_config(head, config);
664                         head->r.bit++;
665                         break;
666                 }
667                 if (head->r.bit == TOMOYO_MAX_MAC_INDEX
668                     + TOMOYO_MAX_MAC_CATEGORY_INDEX) {
669                         head->r.index++;
670                         head->r.step = 1;
671                 }
672                 break;
673         }
674         if (tomoyo_flush(head))
675                 goto next;
676 }
677
678 static bool tomoyo_same_manager(const struct tomoyo_acl_head *a,
679                                 const struct tomoyo_acl_head *b)
680 {
681         return container_of(a, struct tomoyo_manager, head)->manager ==
682                 container_of(b, struct tomoyo_manager, head)->manager;
683 }
684
685 /**
686  * tomoyo_update_manager_entry - Add a manager entry.
687  *
688  * @manager:   The path to manager or the domainnamme.
689  * @is_delete: True if it is a delete request.
690  *
691  * Returns 0 on success, negative value otherwise.
692  *
693  * Caller holds tomoyo_read_lock().
694  */
695 static int tomoyo_update_manager_entry(const char *manager,
696                                        const bool is_delete)
697 {
698         struct tomoyo_manager e = { };
699         struct tomoyo_acl_param param = {
700                 /* .ns = &tomoyo_kernel_namespace, */
701                 .is_delete = is_delete,
702                 .list = &tomoyo_kernel_namespace.
703                 policy_list[TOMOYO_ID_MANAGER],
704         };
705         int error = is_delete ? -ENOENT : -ENOMEM;
706         if (tomoyo_domain_def(manager)) {
707                 if (!tomoyo_correct_domain(manager))
708                         return -EINVAL;
709                 e.is_domain = true;
710         } else {
711                 if (!tomoyo_correct_path(manager))
712                         return -EINVAL;
713         }
714         e.manager = tomoyo_get_name(manager);
715         if (e.manager) {
716                 error = tomoyo_update_policy(&e.head, sizeof(e), &param,
717                                              tomoyo_same_manager);
718                 tomoyo_put_name(e.manager);
719         }
720         return error;
721 }
722
723 /**
724  * tomoyo_write_manager - Write manager policy.
725  *
726  * @head: Pointer to "struct tomoyo_io_buffer".
727  *
728  * Returns 0 on success, negative value otherwise.
729  *
730  * Caller holds tomoyo_read_lock().
731  */
732 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
733 {
734         char *data = head->write_buf;
735
736         if (!strcmp(data, "manage_by_non_root")) {
737                 tomoyo_manage_by_non_root = !head->w.is_delete;
738                 return 0;
739         }
740         return tomoyo_update_manager_entry(data, head->w.is_delete);
741 }
742
743 /**
744  * tomoyo_read_manager - Read manager policy.
745  *
746  * @head: Pointer to "struct tomoyo_io_buffer".
747  *
748  * Caller holds tomoyo_read_lock().
749  */
750 static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
751 {
752         if (head->r.eof)
753                 return;
754         list_for_each_cookie(head->r.acl, &tomoyo_kernel_namespace.
755                              policy_list[TOMOYO_ID_MANAGER]) {
756                 struct tomoyo_manager *ptr =
757                         list_entry(head->r.acl, typeof(*ptr), head.list);
758                 if (ptr->head.is_deleted)
759                         continue;
760                 if (!tomoyo_flush(head))
761                         return;
762                 tomoyo_set_string(head, ptr->manager->name);
763                 tomoyo_set_lf(head);
764         }
765         head->r.eof = true;
766 }
767
768 /**
769  * tomoyo_manager - Check whether the current process is a policy manager.
770  *
771  * Returns true if the current process is permitted to modify policy
772  * via /sys/kernel/security/tomoyo/ interface.
773  *
774  * Caller holds tomoyo_read_lock().
775  */
776 static bool tomoyo_manager(void)
777 {
778         struct tomoyo_manager *ptr;
779         const char *exe;
780         const struct task_struct *task = current;
781         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
782         bool found = false;
783
784         if (!tomoyo_policy_loaded)
785                 return true;
786         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
787                 return false;
788         list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
789                                 policy_list[TOMOYO_ID_MANAGER], head.list) {
790                 if (!ptr->head.is_deleted && ptr->is_domain
791                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
792                         found = true;
793                         break;
794                 }
795         }
796         if (found)
797                 return true;
798         exe = tomoyo_get_exe();
799         if (!exe)
800                 return false;
801         list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
802                                 policy_list[TOMOYO_ID_MANAGER], head.list) {
803                 if (!ptr->head.is_deleted && !ptr->is_domain
804                     && !strcmp(exe, ptr->manager->name)) {
805                         found = true;
806                         break;
807                 }
808         }
809         if (!found) { /* Reduce error messages. */
810                 static pid_t last_pid;
811                 const pid_t pid = current->pid;
812                 if (last_pid != pid) {
813                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
814                                "update policies.\n", domainname->name, exe);
815                         last_pid = pid;
816                 }
817         }
818         kfree(exe);
819         return found;
820 }
821
822 /**
823  * tomoyo_select_domain - Parse select command.
824  *
825  * @head: Pointer to "struct tomoyo_io_buffer".
826  * @data: String to parse.
827  *
828  * Returns true on success, false otherwise.
829  *
830  * Caller holds tomoyo_read_lock().
831  */
832 static bool tomoyo_select_domain(struct tomoyo_io_buffer *head,
833                                  const char *data)
834 {
835         unsigned int pid;
836         struct tomoyo_domain_info *domain = NULL;
837         bool global_pid = false;
838         if (strncmp(data, "select ", 7))
839                 return false;
840         data += 7;
841         if (sscanf(data, "pid=%u", &pid) == 1 ||
842             (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
843                 struct task_struct *p;
844                 rcu_read_lock();
845                 read_lock(&tasklist_lock);
846                 if (global_pid)
847                         p = find_task_by_pid_ns(pid, &init_pid_ns);
848                 else
849                         p = find_task_by_vpid(pid);
850                 if (p)
851                         domain = tomoyo_real_domain(p);
852                 read_unlock(&tasklist_lock);
853                 rcu_read_unlock();
854         } else if (!strncmp(data, "domain=", 7)) {
855                 if (tomoyo_domain_def(data + 7))
856                         domain = tomoyo_find_domain(data + 7);
857         } else
858                 return false;
859         head->w.domain = domain;
860         /* Accessing read_buf is safe because head->io_sem is held. */
861         if (!head->read_buf)
862                 return true; /* Do nothing if open(O_WRONLY). */
863         memset(&head->r, 0, sizeof(head->r));
864         head->r.print_this_domain_only = true;
865         if (domain)
866                 head->r.domain = &domain->list;
867         else
868                 head->r.eof = 1;
869         tomoyo_io_printf(head, "# select %s\n", data);
870         if (domain && domain->is_deleted)
871                 tomoyo_io_printf(head, "# This is a deleted domain.\n");
872         return true;
873 }
874
875 /**
876  * tomoyo_delete_domain - Delete a domain.
877  *
878  * @domainname: The name of domain.
879  *
880  * Returns 0.
881  *
882  * Caller holds tomoyo_read_lock().
883  */
884 static int tomoyo_delete_domain(char *domainname)
885 {
886         struct tomoyo_domain_info *domain;
887         struct tomoyo_path_info name;
888
889         name.name = domainname;
890         tomoyo_fill_path_info(&name);
891         if (mutex_lock_interruptible(&tomoyo_policy_lock))
892                 return 0;
893         /* Is there an active domain? */
894         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
895                 /* Never delete tomoyo_kernel_domain */
896                 if (domain == &tomoyo_kernel_domain)
897                         continue;
898                 if (domain->is_deleted ||
899                     tomoyo_pathcmp(domain->domainname, &name))
900                         continue;
901                 domain->is_deleted = true;
902                 break;
903         }
904         mutex_unlock(&tomoyo_policy_lock);
905         return 0;
906 }
907
908 /**
909  * tomoyo_write_domain2 - Write domain policy.
910  *
911  * @ns:        Pointer to "struct tomoyo_policy_namespace".
912  * @list:      Pointer to "struct list_head".
913  * @data:      Policy to be interpreted.
914  * @is_delete: True if it is a delete request.
915  *
916  * Returns 0 on success, negative value otherwise.
917  *
918  * Caller holds tomoyo_read_lock().
919  */
920 static int tomoyo_write_domain2(struct tomoyo_policy_namespace *ns,
921                                 struct list_head *list, char *data,
922                                 const bool is_delete)
923 {
924         struct tomoyo_acl_param param = {
925                 .ns = ns,
926                 .list = list,
927                 .data = data,
928                 .is_delete = is_delete,
929         };
930         static const struct {
931                 const char *keyword;
932                 int (*write) (struct tomoyo_acl_param *);
933         } tomoyo_callback[1] = {
934                 { "file ", tomoyo_write_file },
935         };
936         u8 i;
937         for (i = 0; i < 1; i++) {
938                 if (!tomoyo_str_starts(&param.data,
939                                        tomoyo_callback[i].keyword))
940                         continue;
941                 return tomoyo_callback[i].write(&param);
942         }
943         return -EINVAL;
944 }
945
946 /* String table for domain flags. */
947 const char * const tomoyo_dif[TOMOYO_MAX_DOMAIN_INFO_FLAGS] = {
948         [TOMOYO_DIF_QUOTA_WARNED]      = "quota_exceeded\n",
949         [TOMOYO_DIF_TRANSITION_FAILED] = "transition_failed\n",
950 };
951
952 /**
953  * tomoyo_write_domain - Write domain policy.
954  *
955  * @head: Pointer to "struct tomoyo_io_buffer".
956  *
957  * Returns 0 on success, negative value otherwise.
958  *
959  * Caller holds tomoyo_read_lock().
960  */
961 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
962 {
963         char *data = head->write_buf;
964         struct tomoyo_policy_namespace *ns;
965         struct tomoyo_domain_info *domain = head->w.domain;
966         const bool is_delete = head->w.is_delete;
967         bool is_select = !is_delete && tomoyo_str_starts(&data, "select ");
968         unsigned int profile;
969         if (*data == '<') {
970                 domain = NULL;
971                 if (is_delete)
972                         tomoyo_delete_domain(data);
973                 else if (is_select)
974                         domain = tomoyo_find_domain(data);
975                 else
976                         domain = tomoyo_assign_domain(data, false);
977                 head->w.domain = domain;
978                 return 0;
979         }
980         if (!domain)
981                 return -EINVAL;
982         ns = domain->ns;
983         if (sscanf(data, "use_profile %u", &profile) == 1
984             && profile < TOMOYO_MAX_PROFILES) {
985                 if (!tomoyo_policy_loaded || ns->profile_ptr[profile])
986                         domain->profile = (u8) profile;
987                 return 0;
988         }
989         if (sscanf(data, "use_group %u\n", &profile) == 1
990             && profile < TOMOYO_MAX_ACL_GROUPS) {
991                 if (!is_delete)
992                         domain->group = (u8) profile;
993                 return 0;
994         }
995         for (profile = 0; profile < TOMOYO_MAX_DOMAIN_INFO_FLAGS; profile++) {
996                 const char *cp = tomoyo_dif[profile];
997                 if (strncmp(data, cp, strlen(cp) - 1))
998                         continue;
999                 domain->flags[profile] = !is_delete;
1000                 return 0;
1001         }
1002         return tomoyo_write_domain2(ns, &domain->acl_info_list, data,
1003                                     is_delete);
1004 }
1005
1006 /**
1007  * tomoyo_set_group - Print "acl_group " header keyword and category name.
1008  *
1009  * @head:     Pointer to "struct tomoyo_io_buffer".
1010  * @category: Category name.
1011  *
1012  * Returns nothing.
1013  */
1014 static void tomoyo_set_group(struct tomoyo_io_buffer *head,
1015                              const char *category)
1016 {
1017         if (head->type == TOMOYO_EXCEPTIONPOLICY) {
1018                 tomoyo_print_namespace(head);
1019                 tomoyo_io_printf(head, "acl_group %u ",
1020                                  head->r.acl_group_index);
1021         }
1022         tomoyo_set_string(head, category);
1023 }
1024
1025 /**
1026  * tomoyo_print_entry - Print an ACL entry.
1027  *
1028  * @head: Pointer to "struct tomoyo_io_buffer".
1029  * @acl:  Pointer to an ACL entry.
1030  *
1031  * Returns true on success, false otherwise.
1032  */
1033 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
1034                                struct tomoyo_acl_info *acl)
1035 {
1036         const u8 acl_type = acl->type;
1037         bool first = true;
1038         u8 bit;
1039
1040         if (acl->is_deleted)
1041                 return true;
1042         if (!tomoyo_flush(head))
1043                 return false;
1044         else if (acl_type == TOMOYO_TYPE_PATH_ACL) {
1045                 struct tomoyo_path_acl *ptr =
1046                         container_of(acl, typeof(*ptr), head);
1047                 const u16 perm = ptr->perm;
1048                 for (bit = 0; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
1049                         if (!(perm & (1 << bit)))
1050                                 continue;
1051                         if (head->r.print_transition_related_only &&
1052                             bit != TOMOYO_TYPE_EXECUTE)
1053                                 continue;
1054                         if (first) {
1055                                 tomoyo_set_group(head, "file ");
1056                                 first = false;
1057                         } else {
1058                                 tomoyo_set_slash(head);
1059                         }
1060                         tomoyo_set_string(head, tomoyo_path_keyword[bit]);
1061                 }
1062                 if (first)
1063                         return true;
1064                 tomoyo_print_name_union(head, &ptr->name);
1065         } else if (head->r.print_transition_related_only) {
1066                 return true;
1067         } else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
1068                 struct tomoyo_path2_acl *ptr =
1069                         container_of(acl, typeof(*ptr), head);
1070                 const u8 perm = ptr->perm;
1071                 for (bit = 0; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
1072                         if (!(perm & (1 << bit)))
1073                                 continue;
1074                         if (first) {
1075                                 tomoyo_set_group(head, "file ");
1076                                 first = false;
1077                         } else {
1078                                 tomoyo_set_slash(head);
1079                         }
1080                         tomoyo_set_string(head, tomoyo_mac_keywords
1081                                           [tomoyo_pp2mac[bit]]);
1082                 }
1083                 if (first)
1084                         return true;
1085                 tomoyo_print_name_union(head, &ptr->name1);
1086                 tomoyo_print_name_union(head, &ptr->name2);
1087         } else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
1088                 struct tomoyo_path_number_acl *ptr =
1089                         container_of(acl, typeof(*ptr), head);
1090                 const u8 perm = ptr->perm;
1091                 for (bit = 0; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION; bit++) {
1092                         if (!(perm & (1 << bit)))
1093                                 continue;
1094                         if (first) {
1095                                 tomoyo_set_group(head, "file ");
1096                                 first = false;
1097                         } else {
1098                                 tomoyo_set_slash(head);
1099                         }
1100                         tomoyo_set_string(head, tomoyo_mac_keywords
1101                                           [tomoyo_pn2mac[bit]]);
1102                 }
1103                 if (first)
1104                         return true;
1105                 tomoyo_print_name_union(head, &ptr->name);
1106                 tomoyo_print_number_union(head, &ptr->number);
1107         } else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
1108                 struct tomoyo_mkdev_acl *ptr =
1109                         container_of(acl, typeof(*ptr), head);
1110                 const u8 perm = ptr->perm;
1111                 for (bit = 0; bit < TOMOYO_MAX_MKDEV_OPERATION; bit++) {
1112                         if (!(perm & (1 << bit)))
1113                                 continue;
1114                         if (first) {
1115                                 tomoyo_set_group(head, "file ");
1116                                 first = false;
1117                         } else {
1118                                 tomoyo_set_slash(head);
1119                         }
1120                         tomoyo_set_string(head, tomoyo_mac_keywords
1121                                           [tomoyo_pnnn2mac[bit]]);
1122                 }
1123                 if (first)
1124                         return true;
1125                 tomoyo_print_name_union(head, &ptr->name);
1126                 tomoyo_print_number_union(head, &ptr->mode);
1127                 tomoyo_print_number_union(head, &ptr->major);
1128                 tomoyo_print_number_union(head, &ptr->minor);
1129         } else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
1130                 struct tomoyo_mount_acl *ptr =
1131                         container_of(acl, typeof(*ptr), head);
1132                 tomoyo_set_group(head, "file mount");
1133                 tomoyo_print_name_union(head, &ptr->dev_name);
1134                 tomoyo_print_name_union(head, &ptr->dir_name);
1135                 tomoyo_print_name_union(head, &ptr->fs_type);
1136                 tomoyo_print_number_union(head, &ptr->flags);
1137         }
1138         tomoyo_set_lf(head);
1139         return true;
1140 }
1141
1142 /**
1143  * tomoyo_read_domain2 - Read domain policy.
1144  *
1145  * @head: Pointer to "struct tomoyo_io_buffer".
1146  * @list: Pointer to "struct list_head".
1147  *
1148  * Caller holds tomoyo_read_lock().
1149  *
1150  * Returns true on success, false otherwise.
1151  */
1152 static bool tomoyo_read_domain2(struct tomoyo_io_buffer *head,
1153                                 struct list_head *list)
1154 {
1155         list_for_each_cookie(head->r.acl, list) {
1156                 struct tomoyo_acl_info *ptr =
1157                         list_entry(head->r.acl, typeof(*ptr), list);
1158                 if (!tomoyo_print_entry(head, ptr))
1159                         return false;
1160         }
1161         head->r.acl = NULL;
1162         return true;
1163 }
1164
1165 /**
1166  * tomoyo_read_domain - Read domain policy.
1167  *
1168  * @head: Pointer to "struct tomoyo_io_buffer".
1169  *
1170  * Caller holds tomoyo_read_lock().
1171  */
1172 static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
1173 {
1174         if (head->r.eof)
1175                 return;
1176         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1177                 struct tomoyo_domain_info *domain =
1178                         list_entry(head->r.domain, typeof(*domain), list);
1179                 switch (head->r.step) {
1180                         u8 i;
1181                 case 0:
1182                         if (domain->is_deleted &&
1183                             !head->r.print_this_domain_only)
1184                                 continue;
1185                         /* Print domainname and flags. */
1186                         tomoyo_set_string(head, domain->domainname->name);
1187                         tomoyo_set_lf(head);
1188                         tomoyo_io_printf(head, "use_profile %u\n",
1189                                          domain->profile);
1190                         tomoyo_io_printf(head, "use_group %u\n",
1191                                          domain->group);
1192                         for (i = 0; i < TOMOYO_MAX_DOMAIN_INFO_FLAGS; i++)
1193                                 if (domain->flags[i])
1194                                         tomoyo_set_string(head, tomoyo_dif[i]);
1195                         head->r.step++;
1196                         tomoyo_set_lf(head);
1197                         /* fall through */
1198                 case 1:
1199                         if (!tomoyo_read_domain2(head, &domain->acl_info_list))
1200                                 return;
1201                         head->r.step++;
1202                         if (!tomoyo_set_lf(head))
1203                                 return;
1204                         /* fall through */
1205                 case 2:
1206                         head->r.step = 0;
1207                         if (head->r.print_this_domain_only)
1208                                 goto done;
1209                 }
1210         }
1211  done:
1212         head->r.eof = true;
1213 }
1214
1215 /**
1216  * tomoyo_write_domain_profile - Assign profile for specified domain.
1217  *
1218  * @head: Pointer to "struct tomoyo_io_buffer".
1219  *
1220  * Returns 0 on success, -EINVAL otherwise.
1221  *
1222  * This is equivalent to doing
1223  *
1224  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
1225  *     /usr/sbin/tomoyo-loadpolicy -d
1226  *
1227  * Caller holds tomoyo_read_lock().
1228  */
1229 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
1230 {
1231         char *data = head->write_buf;
1232         char *cp = strchr(data, ' ');
1233         struct tomoyo_domain_info *domain;
1234         unsigned long profile;
1235
1236         if (!cp)
1237                 return -EINVAL;
1238         *cp = '\0';
1239         domain = tomoyo_find_domain(cp + 1);
1240         if (strict_strtoul(data, 10, &profile))
1241                 return -EINVAL;
1242         if (domain && (!tomoyo_policy_loaded ||
1243                        head->w.ns->profile_ptr[(u8) profile]))
1244                 domain->profile = (u8) profile;
1245         return 0;
1246 }
1247
1248 /**
1249  * tomoyo_read_domain_profile - Read only domainname and profile.
1250  *
1251  * @head: Pointer to "struct tomoyo_io_buffer".
1252  *
1253  * Returns list of profile number and domainname pairs.
1254  *
1255  * This is equivalent to doing
1256  *
1257  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
1258  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
1259  *     domainname = $0; } else if ( $1 == "use_profile" ) {
1260  *     print $2 " " domainname; domainname = ""; } } ; '
1261  *
1262  * Caller holds tomoyo_read_lock().
1263  */
1264 static void tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
1265 {
1266         if (head->r.eof)
1267                 return;
1268         list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1269                 struct tomoyo_domain_info *domain =
1270                         list_entry(head->r.domain, typeof(*domain), list);
1271                 if (domain->is_deleted)
1272                         continue;
1273                 if (!tomoyo_flush(head))
1274                         return;
1275                 tomoyo_io_printf(head, "%u ", domain->profile);
1276                 tomoyo_set_string(head, domain->domainname->name);
1277                 tomoyo_set_lf(head);
1278         }
1279         head->r.eof = true;
1280 }
1281
1282 /**
1283  * tomoyo_write_pid: Specify PID to obtain domainname.
1284  *
1285  * @head: Pointer to "struct tomoyo_io_buffer".
1286  *
1287  * Returns 0.
1288  */
1289 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1290 {
1291         head->r.eof = false;
1292         return 0;
1293 }
1294
1295 /**
1296  * tomoyo_read_pid - Get domainname of the specified PID.
1297  *
1298  * @head: Pointer to "struct tomoyo_io_buffer".
1299  *
1300  * Returns the domainname which the specified PID is in on success,
1301  * empty string otherwise.
1302  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1303  * using read()/write() interface rather than sysctl() interface.
1304  */
1305 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1306 {
1307         char *buf = head->write_buf;
1308         bool global_pid = false;
1309         unsigned int pid;
1310         struct task_struct *p;
1311         struct tomoyo_domain_info *domain = NULL;
1312
1313         /* Accessing write_buf is safe because head->io_sem is held. */
1314         if (!buf) {
1315                 head->r.eof = true;
1316                 return; /* Do nothing if open(O_RDONLY). */
1317         }
1318         if (head->r.w_pos || head->r.eof)
1319                 return;
1320         head->r.eof = true;
1321         if (tomoyo_str_starts(&buf, "global-pid "))
1322                 global_pid = true;
1323         pid = (unsigned int) simple_strtoul(buf, NULL, 10);
1324         rcu_read_lock();
1325         read_lock(&tasklist_lock);
1326         if (global_pid)
1327                 p = find_task_by_pid_ns(pid, &init_pid_ns);
1328         else
1329                 p = find_task_by_vpid(pid);
1330         if (p)
1331                 domain = tomoyo_real_domain(p);
1332         read_unlock(&tasklist_lock);
1333         rcu_read_unlock();
1334         if (!domain)
1335                 return;
1336         tomoyo_io_printf(head, "%u %u ", pid, domain->profile);
1337         tomoyo_set_string(head, domain->domainname->name);
1338 }
1339
1340 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1341         [TOMOYO_TRANSITION_CONTROL_NO_RESET]      = "no_reset_domain ",
1342         [TOMOYO_TRANSITION_CONTROL_RESET]         = "reset_domain ",
1343         [TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain ",
1344         [TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain ",
1345         [TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain ",
1346         [TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain ",
1347 };
1348
1349 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1350         [TOMOYO_PATH_GROUP]   = "path_group ",
1351         [TOMOYO_NUMBER_GROUP] = "number_group ",
1352 };
1353
1354 /**
1355  * tomoyo_write_exception - Write exception policy.
1356  *
1357  * @head: Pointer to "struct tomoyo_io_buffer".
1358  *
1359  * Returns 0 on success, negative value otherwise.
1360  *
1361  * Caller holds tomoyo_read_lock().
1362  */
1363 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
1364 {
1365         const bool is_delete = head->w.is_delete;
1366         struct tomoyo_acl_param param = {
1367                 .ns = head->w.ns,
1368                 .is_delete = is_delete,
1369                 .data = head->write_buf,
1370         };
1371         u8 i;
1372         if (tomoyo_str_starts(&param.data, "aggregator "))
1373                 return tomoyo_write_aggregator(&param);
1374         for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
1375                 if (tomoyo_str_starts(&param.data, tomoyo_transition_type[i]))
1376                         return tomoyo_write_transition_control(&param, i);
1377         for (i = 0; i < TOMOYO_MAX_GROUP; i++)
1378                 if (tomoyo_str_starts(&param.data, tomoyo_group_name[i]))
1379                         return tomoyo_write_group(&param, i);
1380         if (tomoyo_str_starts(&param.data, "acl_group ")) {
1381                 unsigned int group;
1382                 char *data;
1383                 group = simple_strtoul(param.data, &data, 10);
1384                 if (group < TOMOYO_MAX_ACL_GROUPS && *data++ == ' ')
1385                         return tomoyo_write_domain2
1386                                 (head->w.ns, &head->w.ns->acl_group[group],
1387                                  data, is_delete);
1388         }
1389         return -EINVAL;
1390 }
1391
1392 /**
1393  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
1394  *
1395  * @head: Pointer to "struct tomoyo_io_buffer".
1396  * @idx:  Index number.
1397  *
1398  * Returns true on success, false otherwise.
1399  *
1400  * Caller holds tomoyo_read_lock().
1401  */
1402 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1403 {
1404         struct tomoyo_policy_namespace *ns =
1405                 container_of(head->r.ns, typeof(*ns), namespace_list);
1406         struct list_head *list = &ns->group_list[idx];
1407         list_for_each_cookie(head->r.group, list) {
1408                 struct tomoyo_group *group =
1409                         list_entry(head->r.group, typeof(*group), head.list);
1410                 list_for_each_cookie(head->r.acl, &group->member_list) {
1411                         struct tomoyo_acl_head *ptr =
1412                                 list_entry(head->r.acl, typeof(*ptr), list);
1413                         if (ptr->is_deleted)
1414                                 continue;
1415                         if (!tomoyo_flush(head))
1416                                 return false;
1417                         tomoyo_print_namespace(head);
1418                         tomoyo_set_string(head, tomoyo_group_name[idx]);
1419                         tomoyo_set_string(head, group->group_name->name);
1420                         if (idx == TOMOYO_PATH_GROUP) {
1421                                 tomoyo_set_space(head);
1422                                 tomoyo_set_string(head, container_of
1423                                                (ptr, struct tomoyo_path_group,
1424                                                 head)->member_name->name);
1425                         } else if (idx == TOMOYO_NUMBER_GROUP) {
1426                                 tomoyo_print_number_union(head, &container_of
1427                                                           (ptr,
1428                                                    struct tomoyo_number_group,
1429                                                            head)->number);
1430                         }
1431                         tomoyo_set_lf(head);
1432                 }
1433                 head->r.acl = NULL;
1434         }
1435         head->r.group = NULL;
1436         return true;
1437 }
1438
1439 /**
1440  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1441  *
1442  * @head: Pointer to "struct tomoyo_io_buffer".
1443  * @idx:  Index number.
1444  *
1445  * Returns true on success, false otherwise.
1446  *
1447  * Caller holds tomoyo_read_lock().
1448  */
1449 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1450 {
1451         struct tomoyo_policy_namespace *ns =
1452                 container_of(head->r.ns, typeof(*ns), namespace_list);
1453         struct list_head *list = &ns->policy_list[idx];
1454         list_for_each_cookie(head->r.acl, list) {
1455                 struct tomoyo_acl_head *acl =
1456                         container_of(head->r.acl, typeof(*acl), list);
1457                 if (acl->is_deleted)
1458                         continue;
1459                 if (!tomoyo_flush(head))
1460                         return false;
1461                 switch (idx) {
1462                 case TOMOYO_ID_TRANSITION_CONTROL:
1463                         {
1464                                 struct tomoyo_transition_control *ptr =
1465                                         container_of(acl, typeof(*ptr), head);
1466                                 tomoyo_print_namespace(head);
1467                                 tomoyo_set_string(head, tomoyo_transition_type
1468                                                   [ptr->type]);
1469                                 tomoyo_set_string(head, ptr->program ?
1470                                                   ptr->program->name : "any");
1471                                 tomoyo_set_string(head, " from ");
1472                                 tomoyo_set_string(head, ptr->domainname ?
1473                                                   ptr->domainname->name :
1474                                                   "any");
1475                         }
1476                         break;
1477                 case TOMOYO_ID_AGGREGATOR:
1478                         {
1479                                 struct tomoyo_aggregator *ptr =
1480                                         container_of(acl, typeof(*ptr), head);
1481                                 tomoyo_print_namespace(head);
1482                                 tomoyo_set_string(head, "aggregator ");
1483                                 tomoyo_set_string(head,
1484                                                   ptr->original_name->name);
1485                                 tomoyo_set_space(head);
1486                                 tomoyo_set_string(head,
1487                                                ptr->aggregated_name->name);
1488                         }
1489                         break;
1490                 default:
1491                         continue;
1492                 }
1493                 tomoyo_set_lf(head);
1494         }
1495         head->r.acl = NULL;
1496         return true;
1497 }
1498
1499 /**
1500  * tomoyo_read_exception - Read exception policy.
1501  *
1502  * @head: Pointer to "struct tomoyo_io_buffer".
1503  *
1504  * Caller holds tomoyo_read_lock().
1505  */
1506 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
1507 {
1508         struct tomoyo_policy_namespace *ns =
1509                 container_of(head->r.ns, typeof(*ns), namespace_list);
1510         if (head->r.eof)
1511                 return;
1512         while (head->r.step < TOMOYO_MAX_POLICY &&
1513                tomoyo_read_policy(head, head->r.step))
1514                 head->r.step++;
1515         if (head->r.step < TOMOYO_MAX_POLICY)
1516                 return;
1517         while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1518                tomoyo_read_group(head, head->r.step - TOMOYO_MAX_POLICY))
1519                 head->r.step++;
1520         if (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1521                 return;
1522         while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP
1523                + TOMOYO_MAX_ACL_GROUPS) {
1524                 head->r.acl_group_index = head->r.step - TOMOYO_MAX_POLICY
1525                         - TOMOYO_MAX_GROUP;
1526                 if (!tomoyo_read_domain2(head, &ns->acl_group
1527                                          [head->r.acl_group_index]))
1528                         return;
1529                 head->r.step++;
1530         }
1531         head->r.eof = true;
1532 }
1533
1534 /* Wait queue for kernel -> userspace notification. */
1535 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1536 /* Wait queue for userspace -> kernel notification. */
1537 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_answer_wait);
1538
1539 /* Structure for query. */
1540 struct tomoyo_query {
1541         struct list_head list;
1542         char *query;
1543         size_t query_len;
1544         unsigned int serial;
1545         u8 timer;
1546         u8 answer;
1547         u8 retry;
1548 };
1549
1550 /* The list for "struct tomoyo_query". */
1551 static LIST_HEAD(tomoyo_query_list);
1552
1553 /* Lock for manipulating tomoyo_query_list. */
1554 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1555
1556 /*
1557  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1558  * interface.
1559  */
1560 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1561
1562 /**
1563  * tomoyo_add_entry - Add an ACL to current thread's domain. Used by learning mode.
1564  *
1565  * @domain: Pointer to "struct tomoyo_domain_info".
1566  * @header: Lines containing ACL.
1567  *
1568  * Returns nothing.
1569  */
1570 static void tomoyo_add_entry(struct tomoyo_domain_info *domain, char *header)
1571 {
1572         char *buffer;
1573         char *cp = strchr(header, '\n');
1574         int len;
1575         if (!cp)
1576                 return;
1577         cp = strchr(cp + 1, '\n');
1578         if (!cp)
1579                 return;
1580         *cp++ = '\0';
1581         len = strlen(cp) + 1;
1582         buffer = kmalloc(len, GFP_NOFS);
1583         if (!buffer)
1584                 return;
1585         snprintf(buffer, len - 1, "%s", cp);
1586         tomoyo_normalize_line(buffer);
1587         tomoyo_write_domain2(domain->ns, &domain->acl_info_list, buffer,
1588                              false);
1589         kfree(buffer);
1590 }
1591
1592 /**
1593  * tomoyo_supervisor - Ask for the supervisor's decision.
1594  *
1595  * @r:   Pointer to "struct tomoyo_request_info".
1596  * @fmt: The printf()'s format string, followed by parameters.
1597  *
1598  * Returns 0 if the supervisor decided to permit the access request which
1599  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1600  * supervisor decided to retry the access request which violated the policy in
1601  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1602  */
1603 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1604 {
1605         va_list args;
1606         int error;
1607         int len;
1608         static unsigned int tomoyo_serial;
1609         struct tomoyo_query entry = { };
1610         bool quota_exceeded = false;
1611         va_start(args, fmt);
1612         len = vsnprintf((char *) &len, 1, fmt, args) + 1;
1613         va_end(args);
1614         /* Write /sys/kernel/security/tomoyo/audit. */
1615         va_start(args, fmt);
1616         tomoyo_write_log2(r, len, fmt, args);
1617         va_end(args);
1618         /* Nothing more to do if granted. */
1619         if (r->granted)
1620                 return 0;
1621         switch (r->mode) {
1622         case TOMOYO_CONFIG_ENFORCING:
1623                 error = -EPERM;
1624                 if (atomic_read(&tomoyo_query_observers))
1625                         break;
1626                 goto out;
1627         case TOMOYO_CONFIG_LEARNING:
1628                 error = 0;
1629                 /* Check max_learning_entry parameter. */
1630                 if (tomoyo_domain_quota_is_ok(r))
1631                         break;
1632                 /* fall through */
1633         default:
1634                 return 0;
1635         }
1636         /* Get message. */
1637         va_start(args, fmt);
1638         entry.query = tomoyo_init_log(r, len, fmt, args);
1639         va_end(args);
1640         if (!entry.query)
1641                 goto out;
1642         entry.query_len = strlen(entry.query) + 1;
1643         if (!error) {
1644                 tomoyo_add_entry(r->domain, entry.query);
1645                 goto out;
1646         }
1647         len = tomoyo_round2(entry.query_len);
1648         spin_lock(&tomoyo_query_list_lock);
1649         if (tomoyo_memory_quota[TOMOYO_MEMORY_QUERY] &&
1650             tomoyo_memory_used[TOMOYO_MEMORY_QUERY] + len
1651             >= tomoyo_memory_quota[TOMOYO_MEMORY_QUERY]) {
1652                 quota_exceeded = true;
1653         } else {
1654                 entry.serial = tomoyo_serial++;
1655                 entry.retry = r->retry;
1656                 tomoyo_memory_used[TOMOYO_MEMORY_QUERY] += len;
1657                 list_add_tail(&entry.list, &tomoyo_query_list);
1658         }
1659         spin_unlock(&tomoyo_query_list_lock);
1660         if (quota_exceeded)
1661                 goto out;
1662         /* Give 10 seconds for supervisor's opinion. */
1663         while (entry.timer < 10) {
1664                 wake_up_all(&tomoyo_query_wait);
1665                 if (wait_event_interruptible_timeout
1666                     (tomoyo_answer_wait, entry.answer ||
1667                      !atomic_read(&tomoyo_query_observers), HZ))
1668                         break;
1669                 else
1670                         entry.timer++;
1671         }
1672         spin_lock(&tomoyo_query_list_lock);
1673         list_del(&entry.list);
1674         tomoyo_memory_used[TOMOYO_MEMORY_QUERY] -= len;
1675         spin_unlock(&tomoyo_query_list_lock);
1676         switch (entry.answer) {
1677         case 3: /* Asked to retry by administrator. */
1678                 error = TOMOYO_RETRY_REQUEST;
1679                 r->retry++;
1680                 break;
1681         case 1:
1682                 /* Granted by administrator. */
1683                 error = 0;
1684                 break;
1685         default:
1686                 /* Timed out or rejected by administrator. */
1687                 break;
1688         }
1689 out:
1690         kfree(entry.query);
1691         return error;
1692 }
1693
1694 /**
1695  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1696  *
1697  * @file: Pointer to "struct file".
1698  * @wait: Pointer to "poll_table".
1699  *
1700  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1701  *
1702  * Waits for access requests which violated policy in enforcing mode.
1703  */
1704 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1705 {
1706         struct list_head *tmp;
1707         bool found = false;
1708         u8 i;
1709         for (i = 0; i < 2; i++) {
1710                 spin_lock(&tomoyo_query_list_lock);
1711                 list_for_each(tmp, &tomoyo_query_list) {
1712                         struct tomoyo_query *ptr =
1713                                 list_entry(tmp, typeof(*ptr), list);
1714                         if (ptr->answer)
1715                                 continue;
1716                         found = true;
1717                         break;
1718                 }
1719                 spin_unlock(&tomoyo_query_list_lock);
1720                 if (found)
1721                         return POLLIN | POLLRDNORM;
1722                 if (i)
1723                         break;
1724                 poll_wait(file, &tomoyo_query_wait, wait);
1725         }
1726         return 0;
1727 }
1728
1729 /**
1730  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1731  *
1732  * @head: Pointer to "struct tomoyo_io_buffer".
1733  */
1734 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1735 {
1736         struct list_head *tmp;
1737         unsigned int pos = 0;
1738         size_t len = 0;
1739         char *buf;
1740         if (head->r.w_pos)
1741                 return;
1742         if (head->read_buf) {
1743                 kfree(head->read_buf);
1744                 head->read_buf = NULL;
1745         }
1746         spin_lock(&tomoyo_query_list_lock);
1747         list_for_each(tmp, &tomoyo_query_list) {
1748                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1749                 if (ptr->answer)
1750                         continue;
1751                 if (pos++ != head->r.query_index)
1752                         continue;
1753                 len = ptr->query_len;
1754                 break;
1755         }
1756         spin_unlock(&tomoyo_query_list_lock);
1757         if (!len) {
1758                 head->r.query_index = 0;
1759                 return;
1760         }
1761         buf = kzalloc(len + 32, GFP_NOFS);
1762         if (!buf)
1763                 return;
1764         pos = 0;
1765         spin_lock(&tomoyo_query_list_lock);
1766         list_for_each(tmp, &tomoyo_query_list) {
1767                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1768                 if (ptr->answer)
1769                         continue;
1770                 if (pos++ != head->r.query_index)
1771                         continue;
1772                 /*
1773                  * Some query can be skipped because tomoyo_query_list
1774                  * can change, but I don't care.
1775                  */
1776                 if (len == ptr->query_len)
1777                         snprintf(buf, len + 31, "Q%u-%hu\n%s", ptr->serial,
1778                                  ptr->retry, ptr->query);
1779                 break;
1780         }
1781         spin_unlock(&tomoyo_query_list_lock);
1782         if (buf[0]) {
1783                 head->read_buf = buf;
1784                 head->r.w[head->r.w_pos++] = buf;
1785                 head->r.query_index++;
1786         } else {
1787                 kfree(buf);
1788         }
1789 }
1790
1791 /**
1792  * tomoyo_write_answer - Write the supervisor's decision.
1793  *
1794  * @head: Pointer to "struct tomoyo_io_buffer".
1795  *
1796  * Returns 0 on success, -EINVAL otherwise.
1797  */
1798 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1799 {
1800         char *data = head->write_buf;
1801         struct list_head *tmp;
1802         unsigned int serial;
1803         unsigned int answer;
1804         spin_lock(&tomoyo_query_list_lock);
1805         list_for_each(tmp, &tomoyo_query_list) {
1806                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1807                 ptr->timer = 0;
1808         }
1809         spin_unlock(&tomoyo_query_list_lock);
1810         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1811                 return -EINVAL;
1812         spin_lock(&tomoyo_query_list_lock);
1813         list_for_each(tmp, &tomoyo_query_list) {
1814                 struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1815                 if (ptr->serial != serial)
1816                         continue;
1817                 if (!ptr->answer)
1818                         ptr->answer = answer;
1819                 break;
1820         }
1821         spin_unlock(&tomoyo_query_list_lock);
1822         return 0;
1823 }
1824
1825 /**
1826  * tomoyo_read_version: Get version.
1827  *
1828  * @head: Pointer to "struct tomoyo_io_buffer".
1829  *
1830  * Returns version information.
1831  */
1832 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
1833 {
1834         if (!head->r.eof) {
1835                 tomoyo_io_printf(head, "2.4.0");
1836                 head->r.eof = true;
1837         }
1838 }
1839
1840 /**
1841  * tomoyo_read_self_domain - Get the current process's domainname.
1842  *
1843  * @head: Pointer to "struct tomoyo_io_buffer".
1844  *
1845  * Returns the current process's domainname.
1846  */
1847 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1848 {
1849         if (!head->r.eof) {
1850                 /*
1851                  * tomoyo_domain()->domainname != NULL
1852                  * because every process belongs to a domain and
1853                  * the domain's name cannot be NULL.
1854                  */
1855                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1856                 head->r.eof = true;
1857         }
1858 }
1859
1860 /**
1861  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1862  *
1863  * @type: Type of interface.
1864  * @file: Pointer to "struct file".
1865  *
1866  * Returns 0 on success, negative value otherwise.
1867  */
1868 int tomoyo_open_control(const u8 type, struct file *file)
1869 {
1870         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1871
1872         if (!head)
1873                 return -ENOMEM;
1874         mutex_init(&head->io_sem);
1875         head->type = type;
1876         switch (type) {
1877         case TOMOYO_DOMAINPOLICY:
1878                 /* /sys/kernel/security/tomoyo/domain_policy */
1879                 head->write = tomoyo_write_domain;
1880                 head->read = tomoyo_read_domain;
1881                 break;
1882         case TOMOYO_EXCEPTIONPOLICY:
1883                 /* /sys/kernel/security/tomoyo/exception_policy */
1884                 head->write = tomoyo_write_exception;
1885                 head->read = tomoyo_read_exception;
1886                 break;
1887         case TOMOYO_AUDIT:
1888                 /* /sys/kernel/security/tomoyo/audit */
1889                 head->poll = tomoyo_poll_log;
1890                 head->read = tomoyo_read_log;
1891                 break;
1892         case TOMOYO_SELFDOMAIN:
1893                 /* /sys/kernel/security/tomoyo/self_domain */
1894                 head->read = tomoyo_read_self_domain;
1895                 break;
1896         case TOMOYO_DOMAIN_STATUS:
1897                 /* /sys/kernel/security/tomoyo/.domain_status */
1898                 head->write = tomoyo_write_domain_profile;
1899                 head->read = tomoyo_read_domain_profile;
1900                 break;
1901         case TOMOYO_PROCESS_STATUS:
1902                 /* /sys/kernel/security/tomoyo/.process_status */
1903                 head->write = tomoyo_write_pid;
1904                 head->read = tomoyo_read_pid;
1905                 break;
1906         case TOMOYO_VERSION:
1907                 /* /sys/kernel/security/tomoyo/version */
1908                 head->read = tomoyo_read_version;
1909                 head->readbuf_size = 128;
1910                 break;
1911         case TOMOYO_MEMINFO:
1912                 /* /sys/kernel/security/tomoyo/meminfo */
1913                 head->write = tomoyo_write_memory_quota;
1914                 head->read = tomoyo_read_memory_counter;
1915                 head->readbuf_size = 512;
1916                 break;
1917         case TOMOYO_PROFILE:
1918                 /* /sys/kernel/security/tomoyo/profile */
1919                 head->write = tomoyo_write_profile;
1920                 head->read = tomoyo_read_profile;
1921                 break;
1922         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1923                 head->poll = tomoyo_poll_query;
1924                 head->write = tomoyo_write_answer;
1925                 head->read = tomoyo_read_query;
1926                 break;
1927         case TOMOYO_MANAGER:
1928                 /* /sys/kernel/security/tomoyo/manager */
1929                 head->write = tomoyo_write_manager;
1930                 head->read = tomoyo_read_manager;
1931                 break;
1932         }
1933         if (!(file->f_mode & FMODE_READ)) {
1934                 /*
1935                  * No need to allocate read_buf since it is not opened
1936                  * for reading.
1937                  */
1938                 head->read = NULL;
1939                 head->poll = NULL;
1940         } else if (!head->poll) {
1941                 /* Don't allocate read_buf for poll() access. */
1942                 if (!head->readbuf_size)
1943                         head->readbuf_size = 4096 * 2;
1944                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1945                 if (!head->read_buf) {
1946                         kfree(head);
1947                         return -ENOMEM;
1948                 }
1949         }
1950         if (!(file->f_mode & FMODE_WRITE)) {
1951                 /*
1952                  * No need to allocate write_buf since it is not opened
1953                  * for writing.
1954                  */
1955                 head->write = NULL;
1956         } else if (head->write) {
1957                 head->writebuf_size = 4096 * 2;
1958                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1959                 if (!head->write_buf) {
1960                         kfree(head->read_buf);
1961                         kfree(head);
1962                         return -ENOMEM;
1963                 }
1964         }
1965         /*
1966          * If the file is /sys/kernel/security/tomoyo/query , increment the
1967          * observer counter.
1968          * The obserber counter is used by tomoyo_supervisor() to see if
1969          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1970          */
1971         if (type == TOMOYO_QUERY)
1972                 atomic_inc(&tomoyo_query_observers);
1973         file->private_data = head;
1974         tomoyo_notify_gc(head, true);
1975         return 0;
1976 }
1977
1978 /**
1979  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1980  *
1981  * @file: Pointer to "struct file".
1982  * @wait: Pointer to "poll_table".
1983  *
1984  * Waits for read readiness.
1985  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd and
1986  * /sys/kernel/security/tomoyo/audit is handled by /usr/sbin/tomoyo-auditd.
1987  */
1988 int tomoyo_poll_control(struct file *file, poll_table *wait)
1989 {
1990         struct tomoyo_io_buffer *head = file->private_data;
1991         if (!head->poll)
1992                 return -ENOSYS;
1993         return head->poll(file, wait);
1994 }
1995
1996 /**
1997  * tomoyo_set_namespace_cursor - Set namespace to read.
1998  *
1999  * @head: Pointer to "struct tomoyo_io_buffer".
2000  *
2001  * Returns nothing.
2002  */
2003 static inline void tomoyo_set_namespace_cursor(struct tomoyo_io_buffer *head)
2004 {
2005         struct list_head *ns;
2006         if (head->type != TOMOYO_EXCEPTIONPOLICY &&
2007             head->type != TOMOYO_PROFILE)
2008                 return;
2009         /*
2010          * If this is the first read, or reading previous namespace finished
2011          * and has more namespaces to read, update the namespace cursor.
2012          */
2013         ns = head->r.ns;
2014         if (!ns || (head->r.eof && ns->next != &tomoyo_namespace_list)) {
2015                 /* Clearing is OK because tomoyo_flush() returned true. */
2016                 memset(&head->r, 0, sizeof(head->r));
2017                 head->r.ns = ns ? ns->next : tomoyo_namespace_list.next;
2018         }
2019 }
2020
2021 /**
2022  * tomoyo_has_more_namespace - Check for unread namespaces.
2023  *
2024  * @head: Pointer to "struct tomoyo_io_buffer".
2025  *
2026  * Returns true if we have more entries to print, false otherwise.
2027  */
2028 static inline bool tomoyo_has_more_namespace(struct tomoyo_io_buffer *head)
2029 {
2030         return (head->type == TOMOYO_EXCEPTIONPOLICY ||
2031                 head->type == TOMOYO_PROFILE) && head->r.eof &&
2032                 head->r.ns->next != &tomoyo_namespace_list;
2033 }
2034
2035 /**
2036  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
2037  *
2038  * @head:       Pointer to "struct tomoyo_io_buffer".
2039  * @buffer:     Poiner to buffer to write to.
2040  * @buffer_len: Size of @buffer.
2041  *
2042  * Returns bytes read on success, negative value otherwise.
2043  */
2044 ssize_t tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
2045                             const int buffer_len)
2046 {
2047         int len;
2048         int idx;
2049
2050         if (!head->read)
2051                 return -ENOSYS;
2052         if (mutex_lock_interruptible(&head->io_sem))
2053                 return -EINTR;
2054         head->read_user_buf = buffer;
2055         head->read_user_buf_avail = buffer_len;
2056         idx = tomoyo_read_lock();
2057         if (tomoyo_flush(head))
2058                 /* Call the policy handler. */
2059                 do {
2060                         tomoyo_set_namespace_cursor(head);
2061                         head->read(head);
2062                 } while (tomoyo_flush(head) &&
2063                          tomoyo_has_more_namespace(head));
2064         tomoyo_read_unlock(idx);
2065         len = head->read_user_buf - buffer;
2066         mutex_unlock(&head->io_sem);
2067         return len;
2068 }
2069
2070 /**
2071  * tomoyo_parse_policy - Parse a policy line.
2072  *
2073  * @head: Poiter to "struct tomoyo_io_buffer".
2074  * @line: Line to parse.
2075  *
2076  * Returns 0 on success, negative value otherwise.
2077  *
2078  * Caller holds tomoyo_read_lock().
2079  */
2080 static int tomoyo_parse_policy(struct tomoyo_io_buffer *head, char *line)
2081 {
2082         /* Delete request? */
2083         head->w.is_delete = !strncmp(line, "delete ", 7);
2084         if (head->w.is_delete)
2085                 memmove(line, line + 7, strlen(line + 7) + 1);
2086         /* Selecting namespace to update. */
2087         if (head->type == TOMOYO_EXCEPTIONPOLICY ||
2088             head->type == TOMOYO_PROFILE) {
2089                 if (*line == '<') {
2090                         char *cp = strchr(line, ' ');
2091                         if (cp) {
2092                                 *cp++ = '\0';
2093                                 head->w.ns = tomoyo_assign_namespace(line);
2094                                 memmove(line, cp, strlen(cp) + 1);
2095                         } else
2096                                 head->w.ns = NULL;
2097                 } else
2098                         head->w.ns = &tomoyo_kernel_namespace;
2099                 /* Don't allow updating if namespace is invalid. */
2100                 if (!head->w.ns)
2101                         return -ENOENT;
2102         }
2103         /* Do the update. */
2104         return head->write(head);
2105 }
2106
2107 /**
2108  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
2109  *
2110  * @head:       Pointer to "struct tomoyo_io_buffer".
2111  * @buffer:     Pointer to buffer to read from.
2112  * @buffer_len: Size of @buffer.
2113  *
2114  * Returns @buffer_len on success, negative value otherwise.
2115  */
2116 ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head,
2117                              const char __user *buffer, const int buffer_len)
2118 {
2119         int error = buffer_len;
2120         size_t avail_len = buffer_len;
2121         char *cp0 = head->write_buf;
2122         int idx;
2123         if (!head->write)
2124                 return -ENOSYS;
2125         if (!access_ok(VERIFY_READ, buffer, buffer_len))
2126                 return -EFAULT;
2127         if (mutex_lock_interruptible(&head->io_sem))
2128                 return -EINTR;
2129         idx = tomoyo_read_lock();
2130         /* Read a line and dispatch it to the policy handler. */
2131         while (avail_len > 0) {
2132                 char c;
2133                 if (head->w.avail >= head->writebuf_size - 1) {
2134                         const int len = head->writebuf_size * 2;
2135                         char *cp = kzalloc(len, GFP_NOFS);
2136                         if (!cp) {
2137                                 error = -ENOMEM;
2138                                 break;
2139                         }
2140                         memmove(cp, cp0, head->w.avail);
2141                         kfree(cp0);
2142                         head->write_buf = cp;
2143                         cp0 = cp;
2144                         head->writebuf_size = len;
2145                 }
2146                 if (get_user(c, buffer)) {
2147                         error = -EFAULT;
2148                         break;
2149                 }
2150                 buffer++;
2151                 avail_len--;
2152                 cp0[head->w.avail++] = c;
2153                 if (c != '\n')
2154                         continue;
2155                 cp0[head->w.avail - 1] = '\0';
2156                 head->w.avail = 0;
2157                 tomoyo_normalize_line(cp0);
2158                 if (!strcmp(cp0, "reset")) {
2159                         head->w.ns = &tomoyo_kernel_namespace;
2160                         head->w.domain = NULL;
2161                         memset(&head->r, 0, sizeof(head->r));
2162                         continue;
2163                 }
2164                 /* Don't allow updating policies by non manager programs. */
2165                 switch (head->type) {
2166                 case TOMOYO_PROCESS_STATUS:
2167                         /* This does not write anything. */
2168                         break;
2169                 case TOMOYO_DOMAINPOLICY:
2170                         if (tomoyo_select_domain(head, cp0))
2171                                 continue;
2172                         /* fall through */
2173                 case TOMOYO_EXCEPTIONPOLICY:
2174                         if (!strcmp(cp0, "select transition_only")) {
2175                                 head->r.print_transition_related_only = true;
2176                                 continue;
2177                         }
2178                         /* fall through */
2179                 default:
2180                         if (!tomoyo_manager()) {
2181                                 error = -EPERM;
2182                                 goto out;
2183                         }
2184                 }
2185                 switch (tomoyo_parse_policy(head, cp0)) {
2186                 case -EPERM:
2187                         error = -EPERM;
2188                         goto out;
2189                 }
2190         }
2191 out:
2192         tomoyo_read_unlock(idx);
2193         mutex_unlock(&head->io_sem);
2194         return error;
2195 }
2196
2197 /**
2198  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
2199  *
2200  * @head: Pointer to "struct tomoyo_io_buffer".
2201  *
2202  * Returns 0.
2203  */
2204 int tomoyo_close_control(struct tomoyo_io_buffer *head)
2205 {
2206         /*
2207          * If the file is /sys/kernel/security/tomoyo/query , decrement the
2208          * observer counter.
2209          */
2210         if (head->type == TOMOYO_QUERY &&
2211             atomic_dec_and_test(&tomoyo_query_observers))
2212                 wake_up_all(&tomoyo_answer_wait);
2213         tomoyo_notify_gc(head, false);
2214         return 0;
2215 }
2216
2217 /**
2218  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
2219  */
2220 void tomoyo_check_profile(void)
2221 {
2222         struct tomoyo_domain_info *domain;
2223         const int idx = tomoyo_read_lock();
2224         tomoyo_policy_loaded = true;
2225         printk(KERN_INFO "TOMOYO: 2.4.0\n");
2226         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
2227                 const u8 profile = domain->profile;
2228                 const struct tomoyo_policy_namespace *ns = domain->ns;
2229                 if (ns->profile_version != 20100903)
2230                         printk(KERN_ERR
2231                                "Profile version %u is not supported.\n",
2232                                ns->profile_version);
2233                 else if (!ns->profile_ptr[profile])
2234                         printk(KERN_ERR
2235                                "Profile %u (used by '%s') is not defined.\n",
2236                                profile, domain->domainname->name);
2237                 else
2238                         continue;
2239                 printk(KERN_ERR
2240                        "Userland tools for TOMOYO 2.4 must be installed and "
2241                        "policy must be initialized.\n");
2242                 printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.4/ "
2243                        "for more information.\n");
2244                 panic("STOP!");
2245         }
2246         tomoyo_read_unlock(idx);
2247         printk(KERN_INFO "Mandatory Access Control activated.\n");
2248 }