57ddfc5d9c52ad83daff4b378499dc89c6cffca4
[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 <linux/hardirq.h>
13 #include "common.h"
14
15 /* String table for functionality that takes 4 modes. */
16 static const char *tomoyo_mode_4[4] = {
17         "disabled", "learning", "permissive", "enforcing"
18 };
19 /* String table for functionality that takes 2 modes. */
20 static const char *tomoyo_mode_2[4] = {
21         "disabled", "enabled", "enabled", "enabled"
22 };
23
24 /*
25  * tomoyo_control_array is a static data which contains
26  *
27  *  (1) functionality name used by /sys/kernel/security/tomoyo/profile .
28  *  (2) initial values for "struct tomoyo_profile".
29  *  (3) max values for "struct tomoyo_profile".
30  */
31 static struct {
32         const char *keyword;
33         unsigned int current_value;
34         const unsigned int max_value;
35 } tomoyo_control_array[TOMOYO_MAX_CONTROL_INDEX] = {
36         [TOMOYO_MAC_FOR_FILE]     = { "MAC_FOR_FILE",        0,       3 },
37         [TOMOYO_MAX_ACCEPT_ENTRY] = { "MAX_ACCEPT_ENTRY", 2048, INT_MAX },
38         [TOMOYO_VERBOSE]          = { "TOMOYO_VERBOSE",      1,       1 },
39 };
40
41 /*
42  * tomoyo_profile is a structure which is used for holding the mode of access
43  * controls. TOMOYO has 4 modes: disabled, learning, permissive, enforcing.
44  * An administrator can define up to 256 profiles.
45  * The ->profile of "struct tomoyo_domain_info" is used for remembering
46  * the profile's number (0 - 255) assigned to that domain.
47  */
48 static struct tomoyo_profile {
49         unsigned int value[TOMOYO_MAX_CONTROL_INDEX];
50         const struct tomoyo_path_info *comment;
51 } *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
52
53 /* Permit policy management by non-root user? */
54 static bool tomoyo_manage_by_non_root;
55
56 /* Utility functions. */
57
58 /**
59  * tomoyo_print_name_union - Print a tomoyo_name_union.
60  *
61  * @head: Pointer to "struct tomoyo_io_buffer".
62  * @ptr:  Pointer to "struct tomoyo_name_union".
63  *
64  * Returns true on success, false otherwise.
65  */
66 static bool tomoyo_print_name_union(struct tomoyo_io_buffer *head,
67                                  const struct tomoyo_name_union *ptr)
68 {
69         int pos = head->read_avail;
70         if (pos && head->read_buf[pos - 1] == ' ')
71                 head->read_avail--;
72         if (ptr->is_group)
73                 return tomoyo_io_printf(head, " @%s",
74                                         ptr->group->group_name->name);
75         return tomoyo_io_printf(head, " %s", ptr->filename->name);
76 }
77
78 /**
79  * tomoyo_print_number_union - Print a tomoyo_number_union.
80  *
81  * @head:       Pointer to "struct tomoyo_io_buffer".
82  * @ptr:        Pointer to "struct tomoyo_number_union".
83  *
84  * Returns true on success, false otherwise.
85  */
86 bool tomoyo_print_number_union(struct tomoyo_io_buffer *head,
87                                const struct tomoyo_number_union *ptr)
88 {
89         unsigned long min;
90         unsigned long max;
91         u8 min_type;
92         u8 max_type;
93         if (!tomoyo_io_printf(head, " "))
94                 return false;
95         if (ptr->is_group)
96                 return tomoyo_io_printf(head, "@%s",
97                                         ptr->group->group_name->name);
98         min_type = ptr->min_type;
99         max_type = ptr->max_type;
100         min = ptr->values[0];
101         max = ptr->values[1];
102         switch (min_type) {
103         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
104                 if (!tomoyo_io_printf(head, "0x%lX", min))
105                         return false;
106                 break;
107         case TOMOYO_VALUE_TYPE_OCTAL:
108                 if (!tomoyo_io_printf(head, "0%lo", min))
109                         return false;
110                 break;
111         default:
112                 if (!tomoyo_io_printf(head, "%lu", min))
113                         return false;
114                 break;
115         }
116         if (min == max && min_type == max_type)
117                 return true;
118         switch (max_type) {
119         case TOMOYO_VALUE_TYPE_HEXADECIMAL:
120                 return tomoyo_io_printf(head, "-0x%lX", max);
121         case TOMOYO_VALUE_TYPE_OCTAL:
122                 return tomoyo_io_printf(head, "-0%lo", max);
123         default:
124                 return tomoyo_io_printf(head, "-%lu", max);
125         }
126 }
127
128 /**
129  * tomoyo_io_printf - Transactional printf() to "struct tomoyo_io_buffer" structure.
130  *
131  * @head: Pointer to "struct tomoyo_io_buffer".
132  * @fmt:  The printf()'s format string, followed by parameters.
133  *
134  * Returns true if output was written, false otherwise.
135  *
136  * The snprintf() will truncate, but tomoyo_io_printf() won't.
137  */
138 bool tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
139 {
140         va_list args;
141         int len;
142         int pos = head->read_avail;
143         int size = head->readbuf_size - pos;
144
145         if (size <= 0)
146                 return false;
147         va_start(args, fmt);
148         len = vsnprintf(head->read_buf + pos, size, fmt, args);
149         va_end(args);
150         if (pos + len >= head->readbuf_size)
151                 return false;
152         head->read_avail += len;
153         return true;
154 }
155
156 /**
157  * tomoyo_check_flags - Check mode for specified functionality.
158  *
159  * @domain: Pointer to "struct tomoyo_domain_info".
160  * @index:  The functionality to check mode.
161  *
162  * TOMOYO checks only process context.
163  * This code disables TOMOYO's enforcement in case the function is called from
164  * interrupt context.
165  */
166 unsigned int tomoyo_check_flags(const struct tomoyo_domain_info *domain,
167                                 const u8 index)
168 {
169         const u8 profile = domain->profile;
170
171         if (WARN_ON(in_interrupt()))
172                 return 0;
173         return tomoyo_policy_loaded && index < TOMOYO_MAX_CONTROL_INDEX
174 #if TOMOYO_MAX_PROFILES != 256
175                 && profile < TOMOYO_MAX_PROFILES
176 #endif
177                 && tomoyo_profile_ptr[profile] ?
178                 tomoyo_profile_ptr[profile]->value[index] : 0;
179 }
180
181 /**
182  * tomoyo_verbose_mode - Check whether TOMOYO is verbose mode.
183  *
184  * @domain: Pointer to "struct tomoyo_domain_info".
185  *
186  * Returns true if domain policy violation warning should be printed to
187  * console.
188  */
189 bool tomoyo_verbose_mode(const struct tomoyo_domain_info *domain)
190 {
191         return tomoyo_check_flags(domain, TOMOYO_VERBOSE) != 0;
192 }
193
194 /**
195  * tomoyo_find_or_assign_new_profile - Create a new profile.
196  *
197  * @profile: Profile number to create.
198  *
199  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
200  */
201 static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned
202                                                                 int profile)
203 {
204         struct tomoyo_profile *ptr = NULL;
205         int i;
206
207         if (profile >= TOMOYO_MAX_PROFILES)
208                 return NULL;
209         if (mutex_lock_interruptible(&tomoyo_policy_lock))
210                 return NULL;
211         ptr = tomoyo_profile_ptr[profile];
212         if (ptr)
213                 goto ok;
214         ptr = kmalloc(sizeof(*ptr), GFP_NOFS);
215         if (!tomoyo_memory_ok(ptr)) {
216                 kfree(ptr);
217                 ptr = NULL;
218                 goto ok;
219         }
220         for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++)
221                 ptr->value[i] = tomoyo_control_array[i].current_value;
222         mb(); /* Avoid out-of-order execution. */
223         tomoyo_profile_ptr[profile] = ptr;
224  ok:
225         mutex_unlock(&tomoyo_policy_lock);
226         return ptr;
227 }
228
229 /**
230  * tomoyo_write_profile - Write to profile table.
231  *
232  * @head: Pointer to "struct tomoyo_io_buffer".
233  *
234  * Returns 0 on success, negative value otherwise.
235  */
236 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
237 {
238         char *data = head->write_buf;
239         unsigned int i;
240         unsigned int value;
241         char *cp;
242         struct tomoyo_profile *profile;
243         unsigned long num;
244
245         cp = strchr(data, '-');
246         if (cp)
247                 *cp = '\0';
248         if (strict_strtoul(data, 10, &num))
249                 return -EINVAL;
250         if (cp)
251                 data = cp + 1;
252         profile = tomoyo_find_or_assign_new_profile(num);
253         if (!profile)
254                 return -EINVAL;
255         cp = strchr(data, '=');
256         if (!cp)
257                 return -EINVAL;
258         *cp = '\0';
259         if (!strcmp(data, "COMMENT")) {
260                 const struct tomoyo_path_info *old_comment = profile->comment;
261                 profile->comment = tomoyo_get_name(cp + 1);
262                 tomoyo_put_name(old_comment);
263                 return 0;
264         }
265         for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++) {
266                 if (strcmp(data, tomoyo_control_array[i].keyword))
267                         continue;
268                 if (sscanf(cp + 1, "%u", &value) != 1) {
269                         int j;
270                         const char **modes;
271                         switch (i) {
272                         case TOMOYO_VERBOSE:
273                                 modes = tomoyo_mode_2;
274                                 break;
275                         default:
276                                 modes = tomoyo_mode_4;
277                                 break;
278                         }
279                         for (j = 0; j < 4; j++) {
280                                 if (strcmp(cp + 1, modes[j]))
281                                         continue;
282                                 value = j;
283                                 break;
284                         }
285                         if (j == 4)
286                                 return -EINVAL;
287                 } else if (value > tomoyo_control_array[i].max_value) {
288                         value = tomoyo_control_array[i].max_value;
289                 }
290                 profile->value[i] = value;
291                 return 0;
292         }
293         return -EINVAL;
294 }
295
296 /**
297  * tomoyo_read_profile - Read from profile table.
298  *
299  * @head: Pointer to "struct tomoyo_io_buffer".
300  *
301  * Returns 0.
302  */
303 static int tomoyo_read_profile(struct tomoyo_io_buffer *head)
304 {
305         static const int total = TOMOYO_MAX_CONTROL_INDEX + 1;
306         int step;
307
308         if (head->read_eof)
309                 return 0;
310         for (step = head->read_step; step < TOMOYO_MAX_PROFILES * total;
311              step++) {
312                 const u8 index = step / total;
313                 u8 type = step % total;
314                 const struct tomoyo_profile *profile
315                         = tomoyo_profile_ptr[index];
316                 head->read_step = step;
317                 if (!profile)
318                         continue;
319                 if (!type) { /* Print profile' comment tag. */
320                         if (!tomoyo_io_printf(head, "%u-COMMENT=%s\n",
321                                               index, profile->comment ?
322                                               profile->comment->name : ""))
323                                 break;
324                         continue;
325                 }
326                 type--;
327                 if (type < TOMOYO_MAX_CONTROL_INDEX) {
328                         const unsigned int value = profile->value[type];
329                         const char **modes = NULL;
330                         const char *keyword
331                                 = tomoyo_control_array[type].keyword;
332                         switch (tomoyo_control_array[type].max_value) {
333                         case 3:
334                                 modes = tomoyo_mode_4;
335                                 break;
336                         case 1:
337                                 modes = tomoyo_mode_2;
338                                 break;
339                         }
340                         if (modes) {
341                                 if (!tomoyo_io_printf(head, "%u-%s=%s\n", index,
342                                                       keyword, modes[value]))
343                                         break;
344                         } else {
345                                 if (!tomoyo_io_printf(head, "%u-%s=%u\n", index,
346                                                       keyword, value))
347                                         break;
348                         }
349                 }
350         }
351         if (step == TOMOYO_MAX_PROFILES * total)
352                 head->read_eof = true;
353         return 0;
354 }
355
356 /*
357  * tomoyo_policy_manager_list is used for holding list of domainnames or
358  * programs which are permitted to modify configuration via
359  * /sys/kernel/security/tomoyo/ interface.
360  *
361  * An entry is added by
362  *
363  * # echo '<kernel> /sbin/mingetty /bin/login /bin/bash' > \
364  *                                        /sys/kernel/security/tomoyo/manager
365  *  (if you want to specify by a domainname)
366  *
367  *  or
368  *
369  * # echo '/usr/lib/ccs/editpolicy' > /sys/kernel/security/tomoyo/manager
370  *  (if you want to specify by a program's location)
371  *
372  * and is deleted by
373  *
374  * # echo 'delete <kernel> /sbin/mingetty /bin/login /bin/bash' > \
375  *                                        /sys/kernel/security/tomoyo/manager
376  *
377  *  or
378  *
379  * # echo 'delete /usr/lib/ccs/editpolicy' > \
380  *                                        /sys/kernel/security/tomoyo/manager
381  *
382  * and all entries are retrieved by
383  *
384  * # cat /sys/kernel/security/tomoyo/manager
385  */
386 LIST_HEAD(tomoyo_policy_manager_list);
387
388 /**
389  * tomoyo_update_manager_entry - Add a manager entry.
390  *
391  * @manager:   The path to manager or the domainnamme.
392  * @is_delete: True if it is a delete request.
393  *
394  * Returns 0 on success, negative value otherwise.
395  *
396  * Caller holds tomoyo_read_lock().
397  */
398 static int tomoyo_update_manager_entry(const char *manager,
399                                        const bool is_delete)
400 {
401         struct tomoyo_policy_manager_entry *ptr;
402         struct tomoyo_policy_manager_entry e = { };
403         int error = is_delete ? -ENOENT : -ENOMEM;
404
405         if (tomoyo_is_domain_def(manager)) {
406                 if (!tomoyo_is_correct_domain(manager))
407                         return -EINVAL;
408                 e.is_domain = true;
409         } else {
410                 if (!tomoyo_is_correct_path(manager, 1, -1, -1))
411                         return -EINVAL;
412         }
413         e.manager = tomoyo_get_name(manager);
414         if (!e.manager)
415                 return -ENOMEM;
416         if (mutex_lock_interruptible(&tomoyo_policy_lock))
417                 goto out;
418         list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
419                 if (ptr->manager != e.manager)
420                         continue;
421                 ptr->is_deleted = is_delete;
422                 error = 0;
423                 break;
424         }
425         if (!is_delete && error) {
426                 struct tomoyo_policy_manager_entry *entry =
427                         tomoyo_commit_ok(&e, sizeof(e));
428                 if (entry) {
429                         list_add_tail_rcu(&entry->list,
430                                           &tomoyo_policy_manager_list);
431                         error = 0;
432                 }
433         }
434         mutex_unlock(&tomoyo_policy_lock);
435  out:
436         tomoyo_put_name(e.manager);
437         return error;
438 }
439
440 /**
441  * tomoyo_write_manager_policy - Write manager policy.
442  *
443  * @head: Pointer to "struct tomoyo_io_buffer".
444  *
445  * Returns 0 on success, negative value otherwise.
446  *
447  * Caller holds tomoyo_read_lock().
448  */
449 static int tomoyo_write_manager_policy(struct tomoyo_io_buffer *head)
450 {
451         char *data = head->write_buf;
452         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
453
454         if (!strcmp(data, "manage_by_non_root")) {
455                 tomoyo_manage_by_non_root = !is_delete;
456                 return 0;
457         }
458         return tomoyo_update_manager_entry(data, is_delete);
459 }
460
461 /**
462  * tomoyo_read_manager_policy - Read manager policy.
463  *
464  * @head: Pointer to "struct tomoyo_io_buffer".
465  *
466  * Returns 0.
467  *
468  * Caller holds tomoyo_read_lock().
469  */
470 static int tomoyo_read_manager_policy(struct tomoyo_io_buffer *head)
471 {
472         struct list_head *pos;
473         bool done = true;
474
475         if (head->read_eof)
476                 return 0;
477         list_for_each_cookie(pos, head->read_var2,
478                              &tomoyo_policy_manager_list) {
479                 struct tomoyo_policy_manager_entry *ptr;
480                 ptr = list_entry(pos, struct tomoyo_policy_manager_entry,
481                                  list);
482                 if (ptr->is_deleted)
483                         continue;
484                 done = tomoyo_io_printf(head, "%s\n", ptr->manager->name);
485                 if (!done)
486                         break;
487         }
488         head->read_eof = done;
489         return 0;
490 }
491
492 /**
493  * tomoyo_is_policy_manager - Check whether the current process is a policy manager.
494  *
495  * Returns true if the current process is permitted to modify policy
496  * via /sys/kernel/security/tomoyo/ interface.
497  *
498  * Caller holds tomoyo_read_lock().
499  */
500 static bool tomoyo_is_policy_manager(void)
501 {
502         struct tomoyo_policy_manager_entry *ptr;
503         const char *exe;
504         const struct task_struct *task = current;
505         const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
506         bool found = false;
507
508         if (!tomoyo_policy_loaded)
509                 return true;
510         if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
511                 return false;
512         list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
513                 if (!ptr->is_deleted && ptr->is_domain
514                     && !tomoyo_pathcmp(domainname, ptr->manager)) {
515                         found = true;
516                         break;
517                 }
518         }
519         if (found)
520                 return true;
521         exe = tomoyo_get_exe();
522         if (!exe)
523                 return false;
524         list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
525                 if (!ptr->is_deleted && !ptr->is_domain
526                     && !strcmp(exe, ptr->manager->name)) {
527                         found = true;
528                         break;
529                 }
530         }
531         if (!found) { /* Reduce error messages. */
532                 static pid_t last_pid;
533                 const pid_t pid = current->pid;
534                 if (last_pid != pid) {
535                         printk(KERN_WARNING "%s ( %s ) is not permitted to "
536                                "update policies.\n", domainname->name, exe);
537                         last_pid = pid;
538                 }
539         }
540         kfree(exe);
541         return found;
542 }
543
544 /**
545  * tomoyo_is_select_one - Parse select command.
546  *
547  * @head: Pointer to "struct tomoyo_io_buffer".
548  * @data: String to parse.
549  *
550  * Returns true on success, false otherwise.
551  *
552  * Caller holds tomoyo_read_lock().
553  */
554 static bool tomoyo_is_select_one(struct tomoyo_io_buffer *head,
555                                  const char *data)
556 {
557         unsigned int pid;
558         struct tomoyo_domain_info *domain = NULL;
559
560         if (sscanf(data, "pid=%u", &pid) == 1) {
561                 struct task_struct *p;
562                 rcu_read_lock();
563                 read_lock(&tasklist_lock);
564                 p = find_task_by_vpid(pid);
565                 if (p)
566                         domain = tomoyo_real_domain(p);
567                 read_unlock(&tasklist_lock);
568                 rcu_read_unlock();
569         } else if (!strncmp(data, "domain=", 7)) {
570                 if (tomoyo_is_domain_def(data + 7))
571                         domain = tomoyo_find_domain(data + 7);
572         } else
573                 return false;
574         head->write_var1 = domain;
575         /* Accessing read_buf is safe because head->io_sem is held. */
576         if (!head->read_buf)
577                 return true; /* Do nothing if open(O_WRONLY). */
578         head->read_avail = 0;
579         tomoyo_io_printf(head, "# select %s\n", data);
580         head->read_single_domain = true;
581         head->read_eof = !domain;
582         if (domain) {
583                 struct tomoyo_domain_info *d;
584                 head->read_var1 = NULL;
585                 list_for_each_entry_rcu(d, &tomoyo_domain_list, list) {
586                         if (d == domain)
587                                 break;
588                         head->read_var1 = &d->list;
589                 }
590                 head->read_var2 = NULL;
591                 head->read_bit = 0;
592                 head->read_step = 0;
593                 if (domain->is_deleted)
594                         tomoyo_io_printf(head, "# This is a deleted domain.\n");
595         }
596         return true;
597 }
598
599 /**
600  * tomoyo_delete_domain - Delete a domain.
601  *
602  * @domainname: The name of domain.
603  *
604  * Returns 0.
605  *
606  * Caller holds tomoyo_read_lock().
607  */
608 static int tomoyo_delete_domain(char *domainname)
609 {
610         struct tomoyo_domain_info *domain;
611         struct tomoyo_path_info name;
612
613         name.name = domainname;
614         tomoyo_fill_path_info(&name);
615         if (mutex_lock_interruptible(&tomoyo_policy_lock))
616                 return 0;
617         /* Is there an active domain? */
618         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
619                 /* Never delete tomoyo_kernel_domain */
620                 if (domain == &tomoyo_kernel_domain)
621                         continue;
622                 if (domain->is_deleted ||
623                     tomoyo_pathcmp(domain->domainname, &name))
624                         continue;
625                 domain->is_deleted = true;
626                 break;
627         }
628         mutex_unlock(&tomoyo_policy_lock);
629         return 0;
630 }
631
632 /**
633  * tomoyo_write_domain_policy2 - Write domain policy.
634  *
635  * @head: Pointer to "struct tomoyo_io_buffer".
636  *
637  * Returns 0 on success, negative value otherwise.
638  *
639  * Caller holds tomoyo_read_lock().
640  */
641 static int tomoyo_write_domain_policy2(char *data,
642                                        struct tomoyo_domain_info *domain,
643                                        const bool is_delete)
644 {
645         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_MOUNT))
646                 return tomoyo_write_mount_policy(data, domain, is_delete);
647         return tomoyo_write_file_policy(data, domain, is_delete);
648 }
649
650 /**
651  * tomoyo_write_domain_policy - Write domain policy.
652  *
653  * @head: Pointer to "struct tomoyo_io_buffer".
654  *
655  * Returns 0 on success, negative value otherwise.
656  *
657  * Caller holds tomoyo_read_lock().
658  */
659 static int tomoyo_write_domain_policy(struct tomoyo_io_buffer *head)
660 {
661         char *data = head->write_buf;
662         struct tomoyo_domain_info *domain = head->write_var1;
663         bool is_delete = false;
664         bool is_select = false;
665         unsigned int profile;
666
667         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE))
668                 is_delete = true;
669         else if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_SELECT))
670                 is_select = true;
671         if (is_select && tomoyo_is_select_one(head, data))
672                 return 0;
673         /* Don't allow updating policies by non manager programs. */
674         if (!tomoyo_is_policy_manager())
675                 return -EPERM;
676         if (tomoyo_is_domain_def(data)) {
677                 domain = NULL;
678                 if (is_delete)
679                         tomoyo_delete_domain(data);
680                 else if (is_select)
681                         domain = tomoyo_find_domain(data);
682                 else
683                         domain = tomoyo_find_or_assign_new_domain(data, 0);
684                 head->write_var1 = domain;
685                 return 0;
686         }
687         if (!domain)
688                 return -EINVAL;
689
690         if (sscanf(data, TOMOYO_KEYWORD_USE_PROFILE "%u", &profile) == 1
691             && profile < TOMOYO_MAX_PROFILES) {
692                 if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
693                         domain->profile = (u8) profile;
694                 return 0;
695         }
696         if (!strcmp(data, TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ)) {
697                 domain->ignore_global_allow_read = !is_delete;
698                 return 0;
699         }
700         return tomoyo_write_domain_policy2(data, domain, is_delete);
701 }
702
703 /**
704  * tomoyo_print_path_acl - Print a single path ACL entry.
705  *
706  * @head: Pointer to "struct tomoyo_io_buffer".
707  * @ptr:  Pointer to "struct tomoyo_path_acl".
708  *
709  * Returns true on success, false otherwise.
710  */
711 static bool tomoyo_print_path_acl(struct tomoyo_io_buffer *head,
712                                   struct tomoyo_path_acl *ptr)
713 {
714         int pos;
715         u8 bit;
716         const u16 perm = ptr->perm;
717
718         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
719                 if (!(perm & (1 << bit)))
720                         continue;
721                 /* Print "read/write" instead of "read" and "write". */
722                 if ((bit == TOMOYO_TYPE_READ || bit == TOMOYO_TYPE_WRITE)
723                     && (perm & (1 << TOMOYO_TYPE_READ_WRITE)))
724                         continue;
725                 pos = head->read_avail;
726                 if (!tomoyo_io_printf(head, "allow_%s ",
727                                       tomoyo_path2keyword(bit)) ||
728                     !tomoyo_print_name_union(head, &ptr->name) ||
729                     !tomoyo_io_printf(head, "\n"))
730                         goto out;
731         }
732         head->read_bit = 0;
733         return true;
734  out:
735         head->read_bit = bit;
736         head->read_avail = pos;
737         return false;
738 }
739
740 /**
741  * tomoyo_print_path2_acl - Print a double path ACL entry.
742  *
743  * @head: Pointer to "struct tomoyo_io_buffer".
744  * @ptr:  Pointer to "struct tomoyo_path2_acl".
745  *
746  * Returns true on success, false otherwise.
747  */
748 static bool tomoyo_print_path2_acl(struct tomoyo_io_buffer *head,
749                                    struct tomoyo_path2_acl *ptr)
750 {
751         int pos;
752         const u8 perm = ptr->perm;
753         u8 bit;
754
755         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
756                 if (!(perm & (1 << bit)))
757                         continue;
758                 pos = head->read_avail;
759                 if (!tomoyo_io_printf(head, "allow_%s ",
760                                       tomoyo_path22keyword(bit)) ||
761                     !tomoyo_print_name_union(head, &ptr->name1) ||
762                     !tomoyo_print_name_union(head, &ptr->name2) ||
763                     !tomoyo_io_printf(head, "\n"))
764                         goto out;
765         }
766         head->read_bit = 0;
767         return true;
768  out:
769         head->read_bit = bit;
770         head->read_avail = pos;
771         return false;
772 }
773
774 /**
775  * tomoyo_print_path_number_acl - Print a path_number ACL entry.
776  *
777  * @head: Pointer to "struct tomoyo_io_buffer".
778  * @ptr:  Pointer to "struct tomoyo_path_number_acl".
779  *
780  * Returns true on success, false otherwise.
781  */
782 static bool tomoyo_print_path_number_acl(struct tomoyo_io_buffer *head,
783                                          struct tomoyo_path_number_acl *ptr)
784 {
785         int pos;
786         u8 bit;
787         const u8 perm = ptr->perm;
788         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION;
789              bit++) {
790                 if (!(perm & (1 << bit)))
791                         continue;
792                 pos = head->read_avail;
793                 if (!tomoyo_io_printf(head, "allow_%s",
794                                       tomoyo_path_number2keyword(bit)) ||
795                     !tomoyo_print_name_union(head, &ptr->name) ||
796                     !tomoyo_print_number_union(head, &ptr->number) ||
797                     !tomoyo_io_printf(head, "\n"))
798                         goto out;
799         }
800         head->read_bit = 0;
801         return true;
802  out:
803         head->read_bit = bit;
804         head->read_avail = pos;
805         return false;
806 }
807
808 /**
809  * tomoyo_print_path_number3_acl - Print a path_number3 ACL entry.
810  *
811  * @head: Pointer to "struct tomoyo_io_buffer".
812  * @ptr:  Pointer to "struct tomoyo_path_number3_acl".
813  *
814  * Returns true on success, false otherwise.
815  */
816 static bool tomoyo_print_path_number3_acl(struct tomoyo_io_buffer *head,
817                                           struct tomoyo_path_number3_acl *ptr)
818 {
819         int pos;
820         u8 bit;
821         const u16 perm = ptr->perm;
822         for (bit = head->read_bit; bit < TOMOYO_MAX_PATH_NUMBER3_OPERATION;
823              bit++) {
824                 if (!(perm & (1 << bit)))
825                         continue;
826                 pos = head->read_avail;
827                 if (!tomoyo_io_printf(head, "allow_%s",
828                                       tomoyo_path_number32keyword(bit)) ||
829                     !tomoyo_print_name_union(head, &ptr->name) ||
830                     !tomoyo_print_number_union(head, &ptr->mode) ||
831                     !tomoyo_print_number_union(head, &ptr->major) ||
832                     !tomoyo_print_number_union(head, &ptr->minor) ||
833                     !tomoyo_io_printf(head, "\n"))
834                         goto out;
835         }
836         head->read_bit = 0;
837         return true;
838  out:
839         head->read_bit = bit;
840         head->read_avail = pos;
841         return false;
842 }
843
844 /**
845  * tomoyo_print_mount_acl - Print a mount ACL entry.
846  *
847  * @head: Pointer to "struct tomoyo_io_buffer".
848  * @ptr:  Pointer to "struct tomoyo_mount_acl".
849  *
850  * Returns true on success, false otherwise.
851  */
852 static bool tomoyo_print_mount_acl(struct tomoyo_io_buffer *head,
853                                    struct tomoyo_mount_acl *ptr)
854 {
855         const int pos = head->read_avail;
856         if (!tomoyo_io_printf(head, TOMOYO_KEYWORD_ALLOW_MOUNT) ||
857             !tomoyo_print_name_union(head, &ptr->dev_name) ||
858             !tomoyo_print_name_union(head, &ptr->dir_name) ||
859             !tomoyo_print_name_union(head, &ptr->fs_type) ||
860             !tomoyo_print_number_union(head, &ptr->flags) ||
861             !tomoyo_io_printf(head, "\n")) {
862                 head->read_avail = pos;
863                 return false;
864         }
865         return true;
866 }
867
868 /**
869  * tomoyo_print_entry - Print an ACL entry.
870  *
871  * @head: Pointer to "struct tomoyo_io_buffer".
872  * @ptr:  Pointer to an ACL entry.
873  *
874  * Returns true on success, false otherwise.
875  */
876 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
877                                struct tomoyo_acl_info *ptr)
878 {
879         const u8 acl_type = ptr->type;
880
881         if (acl_type == TOMOYO_TYPE_PATH_ACL) {
882                 struct tomoyo_path_acl *acl
883                         = container_of(ptr, struct tomoyo_path_acl, head);
884                 return tomoyo_print_path_acl(head, acl);
885         }
886         if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
887                 struct tomoyo_path2_acl *acl
888                         = container_of(ptr, struct tomoyo_path2_acl, head);
889                 return tomoyo_print_path2_acl(head, acl);
890         }
891         if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
892                 struct tomoyo_path_number_acl *acl
893                         = container_of(ptr, struct tomoyo_path_number_acl,
894                                        head);
895                 return tomoyo_print_path_number_acl(head, acl);
896         }
897         if (acl_type == TOMOYO_TYPE_PATH_NUMBER3_ACL) {
898                 struct tomoyo_path_number3_acl *acl
899                         = container_of(ptr, struct tomoyo_path_number3_acl,
900                                        head);
901                 return tomoyo_print_path_number3_acl(head, acl);
902         }
903         if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
904                 struct tomoyo_mount_acl *acl
905                         = container_of(ptr, struct tomoyo_mount_acl, head);
906                 return tomoyo_print_mount_acl(head, acl);
907         }
908         BUG(); /* This must not happen. */
909         return false;
910 }
911
912 /**
913  * tomoyo_read_domain_policy - Read domain policy.
914  *
915  * @head: Pointer to "struct tomoyo_io_buffer".
916  *
917  * Returns 0.
918  *
919  * Caller holds tomoyo_read_lock().
920  */
921 static int tomoyo_read_domain_policy(struct tomoyo_io_buffer *head)
922 {
923         struct list_head *dpos;
924         struct list_head *apos;
925         bool done = true;
926
927         if (head->read_eof)
928                 return 0;
929         if (head->read_step == 0)
930                 head->read_step = 1;
931         list_for_each_cookie(dpos, head->read_var1, &tomoyo_domain_list) {
932                 struct tomoyo_domain_info *domain;
933                 const char *quota_exceeded = "";
934                 const char *transition_failed = "";
935                 const char *ignore_global_allow_read = "";
936                 domain = list_entry(dpos, struct tomoyo_domain_info, list);
937                 if (head->read_step != 1)
938                         goto acl_loop;
939                 if (domain->is_deleted && !head->read_single_domain)
940                         continue;
941                 /* Print domainname and flags. */
942                 if (domain->quota_warned)
943                         quota_exceeded = "quota_exceeded\n";
944                 if (domain->transition_failed)
945                         transition_failed = "transition_failed\n";
946                 if (domain->ignore_global_allow_read)
947                         ignore_global_allow_read
948                                 = TOMOYO_KEYWORD_IGNORE_GLOBAL_ALLOW_READ "\n";
949                 done = tomoyo_io_printf(head, "%s\n" TOMOYO_KEYWORD_USE_PROFILE
950                                         "%u\n%s%s%s\n",
951                                         domain->domainname->name,
952                                         domain->profile, quota_exceeded,
953                                         transition_failed,
954                                         ignore_global_allow_read);
955                 if (!done)
956                         break;
957                 head->read_step = 2;
958 acl_loop:
959                 if (head->read_step == 3)
960                         goto tail_mark;
961                 /* Print ACL entries in the domain. */
962                 list_for_each_cookie(apos, head->read_var2,
963                                      &domain->acl_info_list) {
964                         struct tomoyo_acl_info *ptr
965                                 = list_entry(apos, struct tomoyo_acl_info,
966                                              list);
967                         done = tomoyo_print_entry(head, ptr);
968                         if (!done)
969                                 break;
970                 }
971                 if (!done)
972                         break;
973                 head->read_step = 3;
974 tail_mark:
975                 done = tomoyo_io_printf(head, "\n");
976                 if (!done)
977                         break;
978                 head->read_step = 1;
979                 if (head->read_single_domain)
980                         break;
981         }
982         head->read_eof = done;
983         return 0;
984 }
985
986 /**
987  * tomoyo_write_domain_profile - Assign profile for specified domain.
988  *
989  * @head: Pointer to "struct tomoyo_io_buffer".
990  *
991  * Returns 0 on success, -EINVAL otherwise.
992  *
993  * This is equivalent to doing
994  *
995  *     ( echo "select " $domainname; echo "use_profile " $profile ) |
996  *     /usr/lib/ccs/loadpolicy -d
997  *
998  * Caller holds tomoyo_read_lock().
999  */
1000 static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
1001 {
1002         char *data = head->write_buf;
1003         char *cp = strchr(data, ' ');
1004         struct tomoyo_domain_info *domain;
1005         unsigned long profile;
1006
1007         if (!cp)
1008                 return -EINVAL;
1009         *cp = '\0';
1010         domain = tomoyo_find_domain(cp + 1);
1011         if (strict_strtoul(data, 10, &profile))
1012                 return -EINVAL;
1013         if (domain && profile < TOMOYO_MAX_PROFILES
1014             && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
1015                 domain->profile = (u8) profile;
1016         return 0;
1017 }
1018
1019 /**
1020  * tomoyo_read_domain_profile - Read only domainname and profile.
1021  *
1022  * @head: Pointer to "struct tomoyo_io_buffer".
1023  *
1024  * Returns list of profile number and domainname pairs.
1025  *
1026  * This is equivalent to doing
1027  *
1028  *     grep -A 1 '^<kernel>' /sys/kernel/security/tomoyo/domain_policy |
1029  *     awk ' { if ( domainname == "" ) { if ( $1 == "<kernel>" )
1030  *     domainname = $0; } else if ( $1 == "use_profile" ) {
1031  *     print $2 " " domainname; domainname = ""; } } ; '
1032  *
1033  * Caller holds tomoyo_read_lock().
1034  */
1035 static int tomoyo_read_domain_profile(struct tomoyo_io_buffer *head)
1036 {
1037         struct list_head *pos;
1038         bool done = true;
1039
1040         if (head->read_eof)
1041                 return 0;
1042         list_for_each_cookie(pos, head->read_var1, &tomoyo_domain_list) {
1043                 struct tomoyo_domain_info *domain;
1044                 domain = list_entry(pos, struct tomoyo_domain_info, list);
1045                 if (domain->is_deleted)
1046                         continue;
1047                 done = tomoyo_io_printf(head, "%u %s\n", domain->profile,
1048                                         domain->domainname->name);
1049                 if (!done)
1050                         break;
1051         }
1052         head->read_eof = done;
1053         return 0;
1054 }
1055
1056 /**
1057  * tomoyo_write_pid: Specify PID to obtain domainname.
1058  *
1059  * @head: Pointer to "struct tomoyo_io_buffer".
1060  *
1061  * Returns 0.
1062  */
1063 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1064 {
1065         unsigned long pid;
1066         /* No error check. */
1067         strict_strtoul(head->write_buf, 10, &pid);
1068         head->read_step = (int) pid;
1069         head->read_eof = false;
1070         return 0;
1071 }
1072
1073 /**
1074  * tomoyo_read_pid - Get domainname of the specified PID.
1075  *
1076  * @head: Pointer to "struct tomoyo_io_buffer".
1077  *
1078  * Returns the domainname which the specified PID is in on success,
1079  * empty string otherwise.
1080  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1081  * using read()/write() interface rather than sysctl() interface.
1082  */
1083 static int tomoyo_read_pid(struct tomoyo_io_buffer *head)
1084 {
1085         if (head->read_avail == 0 && !head->read_eof) {
1086                 const int pid = head->read_step;
1087                 struct task_struct *p;
1088                 struct tomoyo_domain_info *domain = NULL;
1089                 rcu_read_lock();
1090                 read_lock(&tasklist_lock);
1091                 p = find_task_by_vpid(pid);
1092                 if (p)
1093                         domain = tomoyo_real_domain(p);
1094                 read_unlock(&tasklist_lock);
1095                 rcu_read_unlock();
1096                 if (domain)
1097                         tomoyo_io_printf(head, "%d %u %s", pid, domain->profile,
1098                                          domain->domainname->name);
1099                 head->read_eof = true;
1100         }
1101         return 0;
1102 }
1103
1104 /**
1105  * tomoyo_write_exception_policy - Write exception policy.
1106  *
1107  * @head: Pointer to "struct tomoyo_io_buffer".
1108  *
1109  * Returns 0 on success, negative value otherwise.
1110  *
1111  * Caller holds tomoyo_read_lock().
1112  */
1113 static int tomoyo_write_exception_policy(struct tomoyo_io_buffer *head)
1114 {
1115         char *data = head->write_buf;
1116         bool is_delete = tomoyo_str_starts(&data, TOMOYO_KEYWORD_DELETE);
1117
1118         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_KEEP_DOMAIN))
1119                 return tomoyo_write_domain_keeper_policy(data, false,
1120                                                          is_delete);
1121         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_KEEP_DOMAIN))
1122                 return tomoyo_write_domain_keeper_policy(data, true, is_delete);
1123         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_INITIALIZE_DOMAIN))
1124                 return tomoyo_write_domain_initializer_policy(data, false,
1125                                                               is_delete);
1126         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NO_INITIALIZE_DOMAIN))
1127                 return tomoyo_write_domain_initializer_policy(data, true,
1128                                                               is_delete);
1129         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALIAS))
1130                 return tomoyo_write_alias_policy(data, is_delete);
1131         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_ALLOW_READ))
1132                 return tomoyo_write_globally_readable_policy(data, is_delete);
1133         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_FILE_PATTERN))
1134                 return tomoyo_write_pattern_policy(data, is_delete);
1135         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_DENY_REWRITE))
1136                 return tomoyo_write_no_rewrite_policy(data, is_delete);
1137         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_PATH_GROUP))
1138                 return tomoyo_write_path_group_policy(data, is_delete);
1139         if (tomoyo_str_starts(&data, TOMOYO_KEYWORD_NUMBER_GROUP))
1140                 return tomoyo_write_number_group_policy(data, is_delete);
1141         return -EINVAL;
1142 }
1143
1144 /**
1145  * tomoyo_read_exception_policy - Read exception policy.
1146  *
1147  * @head: Pointer to "struct tomoyo_io_buffer".
1148  *
1149  * Returns 0 on success, -EINVAL otherwise.
1150  *
1151  * Caller holds tomoyo_read_lock().
1152  */
1153 static int tomoyo_read_exception_policy(struct tomoyo_io_buffer *head)
1154 {
1155         if (!head->read_eof) {
1156                 switch (head->read_step) {
1157                 case 0:
1158                         head->read_var2 = NULL;
1159                         head->read_step = 1;
1160                 case 1:
1161                         if (!tomoyo_read_domain_keeper_policy(head))
1162                                 break;
1163                         head->read_var2 = NULL;
1164                         head->read_step = 2;
1165                 case 2:
1166                         if (!tomoyo_read_globally_readable_policy(head))
1167                                 break;
1168                         head->read_var2 = NULL;
1169                         head->read_step = 3;
1170                 case 3:
1171                         head->read_var2 = NULL;
1172                         head->read_step = 4;
1173                 case 4:
1174                         if (!tomoyo_read_domain_initializer_policy(head))
1175                                 break;
1176                         head->read_var2 = NULL;
1177                         head->read_step = 5;
1178                 case 5:
1179                         if (!tomoyo_read_alias_policy(head))
1180                                 break;
1181                         head->read_var2 = NULL;
1182                         head->read_step = 6;
1183                 case 6:
1184                         head->read_var2 = NULL;
1185                         head->read_step = 7;
1186                 case 7:
1187                         if (!tomoyo_read_file_pattern(head))
1188                                 break;
1189                         head->read_var2 = NULL;
1190                         head->read_step = 8;
1191                 case 8:
1192                         if (!tomoyo_read_no_rewrite_policy(head))
1193                                 break;
1194                         head->read_var2 = NULL;
1195                         head->read_step = 9;
1196                 case 9:
1197                         if (!tomoyo_read_path_group_policy(head))
1198                                 break;
1199                         head->read_var1 = NULL;
1200                         head->read_var2 = NULL;
1201                         head->read_step = 10;
1202                 case 10:
1203                         if (!tomoyo_read_number_group_policy(head))
1204                                 break;
1205                         head->read_var1 = NULL;
1206                         head->read_var2 = NULL;
1207                         head->read_step = 11;
1208                 case 11:
1209                         head->read_eof = true;
1210                         break;
1211                 default:
1212                         return -EINVAL;
1213                 }
1214         }
1215         return 0;
1216 }
1217
1218 /**
1219  * tomoyo_print_header - Get header line of audit log.
1220  *
1221  * @r: Pointer to "struct tomoyo_request_info".
1222  *
1223  * Returns string representation.
1224  *
1225  * This function uses kmalloc(), so caller must kfree() if this function
1226  * didn't return NULL.
1227  */
1228 static char *tomoyo_print_header(struct tomoyo_request_info *r)
1229 {
1230         static const char *tomoyo_mode_4[4] = {
1231                 "disabled", "learning", "permissive", "enforcing"
1232         };
1233         struct timeval tv;
1234         const pid_t gpid = task_pid_nr(current);
1235         static const int tomoyo_buffer_len = 4096;
1236         char *buffer = kmalloc(tomoyo_buffer_len, GFP_NOFS);
1237         if (!buffer)
1238                 return NULL;
1239         do_gettimeofday(&tv);
1240         snprintf(buffer, tomoyo_buffer_len - 1,
1241                  "#timestamp=%lu profile=%u mode=%s (global-pid=%u)"
1242                  " task={ pid=%u ppid=%u uid=%u gid=%u euid=%u"
1243                  " egid=%u suid=%u sgid=%u fsuid=%u fsgid=%u }",
1244                  tv.tv_sec, r->profile, tomoyo_mode_4[r->mode], gpid,
1245                  (pid_t) sys_getpid(), (pid_t) sys_getppid(),
1246                  current_uid(), current_gid(), current_euid(),
1247                  current_egid(), current_suid(), current_sgid(),
1248                  current_fsuid(), current_fsgid());
1249         return buffer;
1250 }
1251
1252 /**
1253  * tomoyo_init_audit_log - Allocate buffer for audit logs.
1254  *
1255  * @len: Required size.
1256  * @r:   Pointer to "struct tomoyo_request_info".
1257  *
1258  * Returns pointer to allocated memory.
1259  *
1260  * The @len is updated to add the header lines' size on success.
1261  *
1262  * This function uses kzalloc(), so caller must kfree() if this function
1263  * didn't return NULL.
1264  */
1265 static char *tomoyo_init_audit_log(int *len, struct tomoyo_request_info *r)
1266 {
1267         char *buf = NULL;
1268         const char *header;
1269         const char *domainname;
1270         if (!r->domain)
1271                 r->domain = tomoyo_domain();
1272         domainname = r->domain->domainname->name;
1273         header = tomoyo_print_header(r);
1274         if (!header)
1275                 return NULL;
1276         *len += strlen(domainname) + strlen(header) + 10;
1277         buf = kzalloc(*len, GFP_NOFS);
1278         if (buf)
1279                 snprintf(buf, (*len) - 1, "%s\n%s\n", header, domainname);
1280         kfree(header);
1281         return buf;
1282 }
1283
1284 /* Wait queue for tomoyo_query_list. */
1285 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1286
1287 /* Lock for manipulating tomoyo_query_list. */
1288 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1289
1290 /* Structure for query. */
1291 struct tomoyo_query_entry {
1292         struct list_head list;
1293         char *query;
1294         int query_len;
1295         unsigned int serial;
1296         int timer;
1297         int answer;
1298 };
1299
1300 /* The list for "struct tomoyo_query_entry". */
1301 static LIST_HEAD(tomoyo_query_list);
1302
1303 /*
1304  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1305  * interface.
1306  */
1307 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1308
1309 /**
1310  * tomoyo_supervisor - Ask for the supervisor's decision.
1311  *
1312  * @r:       Pointer to "struct tomoyo_request_info".
1313  * @fmt:     The printf()'s format string, followed by parameters.
1314  *
1315  * Returns 0 if the supervisor decided to permit the access request which
1316  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1317  * supervisor decided to retry the access request which violated the policy in
1318  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1319  */
1320 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1321 {
1322         va_list args;
1323         int error = -EPERM;
1324         int pos;
1325         int len;
1326         static unsigned int tomoyo_serial;
1327         struct tomoyo_query_entry *tomoyo_query_entry = NULL;
1328         bool quota_exceeded = false;
1329         char *header;
1330         switch (r->mode) {
1331                 char *buffer;
1332         case TOMOYO_CONFIG_LEARNING:
1333                 if (!tomoyo_domain_quota_is_ok(r))
1334                         return 0;
1335                 va_start(args, fmt);
1336                 len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 4;
1337                 va_end(args);
1338                 buffer = kmalloc(len, GFP_NOFS);
1339                 if (!buffer)
1340                         return 0;
1341                 va_start(args, fmt);
1342                 vsnprintf(buffer, len - 1, fmt, args);
1343                 va_end(args);
1344                 tomoyo_normalize_line(buffer);
1345                 tomoyo_write_domain_policy2(buffer, r->domain, false);
1346                 kfree(buffer);
1347                 /* fall through */
1348         case TOMOYO_CONFIG_PERMISSIVE:
1349                 return 0;
1350         }
1351         if (!r->domain)
1352                 r->domain = tomoyo_domain();
1353         if (!atomic_read(&tomoyo_query_observers))
1354                 return -EPERM;
1355         va_start(args, fmt);
1356         len = vsnprintf((char *) &pos, sizeof(pos) - 1, fmt, args) + 32;
1357         va_end(args);
1358         header = tomoyo_init_audit_log(&len, r);
1359         if (!header)
1360                 goto out;
1361         tomoyo_query_entry = kzalloc(sizeof(*tomoyo_query_entry), GFP_NOFS);
1362         if (!tomoyo_query_entry)
1363                 goto out;
1364         tomoyo_query_entry->query = kzalloc(len, GFP_NOFS);
1365         if (!tomoyo_query_entry->query)
1366                 goto out;
1367         len = ksize(tomoyo_query_entry->query);
1368         INIT_LIST_HEAD(&tomoyo_query_entry->list);
1369         spin_lock(&tomoyo_query_list_lock);
1370         if (tomoyo_quota_for_query && tomoyo_query_memory_size + len +
1371             sizeof(*tomoyo_query_entry) >= tomoyo_quota_for_query) {
1372                 quota_exceeded = true;
1373         } else {
1374                 tomoyo_query_memory_size += len + sizeof(*tomoyo_query_entry);
1375                 tomoyo_query_entry->serial = tomoyo_serial++;
1376         }
1377         spin_unlock(&tomoyo_query_list_lock);
1378         if (quota_exceeded)
1379                 goto out;
1380         pos = snprintf(tomoyo_query_entry->query, len - 1, "Q%u-%hu\n%s",
1381                        tomoyo_query_entry->serial, r->retry, header);
1382         kfree(header);
1383         header = NULL;
1384         va_start(args, fmt);
1385         vsnprintf(tomoyo_query_entry->query + pos, len - 1 - pos, fmt, args);
1386         tomoyo_query_entry->query_len = strlen(tomoyo_query_entry->query) + 1;
1387         va_end(args);
1388         spin_lock(&tomoyo_query_list_lock);
1389         list_add_tail(&tomoyo_query_entry->list, &tomoyo_query_list);
1390         spin_unlock(&tomoyo_query_list_lock);
1391         /* Give 10 seconds for supervisor's opinion. */
1392         for (tomoyo_query_entry->timer = 0;
1393              atomic_read(&tomoyo_query_observers) && tomoyo_query_entry->timer < 100;
1394              tomoyo_query_entry->timer++) {
1395                 wake_up(&tomoyo_query_wait);
1396                 set_current_state(TASK_INTERRUPTIBLE);
1397                 schedule_timeout(HZ / 10);
1398                 if (tomoyo_query_entry->answer)
1399                         break;
1400         }
1401         spin_lock(&tomoyo_query_list_lock);
1402         list_del(&tomoyo_query_entry->list);
1403         tomoyo_query_memory_size -= len + sizeof(*tomoyo_query_entry);
1404         spin_unlock(&tomoyo_query_list_lock);
1405         switch (tomoyo_query_entry->answer) {
1406         case 3: /* Asked to retry by administrator. */
1407                 error = TOMOYO_RETRY_REQUEST;
1408                 r->retry++;
1409                 break;
1410         case 1:
1411                 /* Granted by administrator. */
1412                 error = 0;
1413                 break;
1414         case 0:
1415                 /* Timed out. */
1416                 break;
1417         default:
1418                 /* Rejected by administrator. */
1419                 break;
1420         }
1421  out:
1422         if (tomoyo_query_entry)
1423                 kfree(tomoyo_query_entry->query);
1424         kfree(tomoyo_query_entry);
1425         kfree(header);
1426         return error;
1427 }
1428
1429 /**
1430  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1431  *
1432  * @file: Pointer to "struct file".
1433  * @wait: Pointer to "poll_table".
1434  *
1435  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1436  *
1437  * Waits for access requests which violated policy in enforcing mode.
1438  */
1439 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1440 {
1441         struct list_head *tmp;
1442         bool found = false;
1443         u8 i;
1444         for (i = 0; i < 2; i++) {
1445                 spin_lock(&tomoyo_query_list_lock);
1446                 list_for_each(tmp, &tomoyo_query_list) {
1447                         struct tomoyo_query_entry *ptr
1448                                 = list_entry(tmp, struct tomoyo_query_entry,
1449                                              list);
1450                         if (ptr->answer)
1451                                 continue;
1452                         found = true;
1453                         break;
1454                 }
1455                 spin_unlock(&tomoyo_query_list_lock);
1456                 if (found)
1457                         return POLLIN | POLLRDNORM;
1458                 if (i)
1459                         break;
1460                 poll_wait(file, &tomoyo_query_wait, wait);
1461         }
1462         return 0;
1463 }
1464
1465 /**
1466  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1467  *
1468  * @head: Pointer to "struct tomoyo_io_buffer".
1469  *
1470  * Returns 0.
1471  */
1472 static int tomoyo_read_query(struct tomoyo_io_buffer *head)
1473 {
1474         struct list_head *tmp;
1475         int pos = 0;
1476         int len = 0;
1477         char *buf;
1478         if (head->read_avail)
1479                 return 0;
1480         if (head->read_buf) {
1481                 kfree(head->read_buf);
1482                 head->read_buf = NULL;
1483                 head->readbuf_size = 0;
1484         }
1485         spin_lock(&tomoyo_query_list_lock);
1486         list_for_each(tmp, &tomoyo_query_list) {
1487                 struct tomoyo_query_entry *ptr
1488                         = list_entry(tmp, struct tomoyo_query_entry, list);
1489                 if (ptr->answer)
1490                         continue;
1491                 if (pos++ != head->read_step)
1492                         continue;
1493                 len = ptr->query_len;
1494                 break;
1495         }
1496         spin_unlock(&tomoyo_query_list_lock);
1497         if (!len) {
1498                 head->read_step = 0;
1499                 return 0;
1500         }
1501         buf = kzalloc(len, GFP_NOFS);
1502         if (!buf)
1503                 return 0;
1504         pos = 0;
1505         spin_lock(&tomoyo_query_list_lock);
1506         list_for_each(tmp, &tomoyo_query_list) {
1507                 struct tomoyo_query_entry *ptr
1508                         = list_entry(tmp, struct tomoyo_query_entry, list);
1509                 if (ptr->answer)
1510                         continue;
1511                 if (pos++ != head->read_step)
1512                         continue;
1513                 /*
1514                  * Some query can be skipped because tomoyo_query_list
1515                  * can change, but I don't care.
1516                  */
1517                 if (len == ptr->query_len)
1518                         memmove(buf, ptr->query, len);
1519                 break;
1520         }
1521         spin_unlock(&tomoyo_query_list_lock);
1522         if (buf[0]) {
1523                 head->read_avail = len;
1524                 head->readbuf_size = head->read_avail;
1525                 head->read_buf = buf;
1526                 head->read_step++;
1527         } else {
1528                 kfree(buf);
1529         }
1530         return 0;
1531 }
1532
1533 /**
1534  * tomoyo_write_answer - Write the supervisor's decision.
1535  *
1536  * @head: Pointer to "struct tomoyo_io_buffer".
1537  *
1538  * Returns 0 on success, -EINVAL otherwise.
1539  */
1540 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
1541 {
1542         char *data = head->write_buf;
1543         struct list_head *tmp;
1544         unsigned int serial;
1545         unsigned int answer;
1546         spin_lock(&tomoyo_query_list_lock);
1547         list_for_each(tmp, &tomoyo_query_list) {
1548                 struct tomoyo_query_entry *ptr
1549                         = list_entry(tmp, struct tomoyo_query_entry, list);
1550                 ptr->timer = 0;
1551         }
1552         spin_unlock(&tomoyo_query_list_lock);
1553         if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
1554                 return -EINVAL;
1555         spin_lock(&tomoyo_query_list_lock);
1556         list_for_each(tmp, &tomoyo_query_list) {
1557                 struct tomoyo_query_entry *ptr
1558                         = list_entry(tmp, struct tomoyo_query_entry, list);
1559                 if (ptr->serial != serial)
1560                         continue;
1561                 if (!ptr->answer)
1562                         ptr->answer = answer;
1563                 break;
1564         }
1565         spin_unlock(&tomoyo_query_list_lock);
1566         return 0;
1567 }
1568
1569 /**
1570  * tomoyo_read_version: Get version.
1571  *
1572  * @head: Pointer to "struct tomoyo_io_buffer".
1573  *
1574  * Returns version information.
1575  */
1576 static int tomoyo_read_version(struct tomoyo_io_buffer *head)
1577 {
1578         if (!head->read_eof) {
1579                 tomoyo_io_printf(head, "2.2.0");
1580                 head->read_eof = true;
1581         }
1582         return 0;
1583 }
1584
1585 /**
1586  * tomoyo_read_self_domain - Get the current process's domainname.
1587  *
1588  * @head: Pointer to "struct tomoyo_io_buffer".
1589  *
1590  * Returns the current process's domainname.
1591  */
1592 static int tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
1593 {
1594         if (!head->read_eof) {
1595                 /*
1596                  * tomoyo_domain()->domainname != NULL
1597                  * because every process belongs to a domain and
1598                  * the domain's name cannot be NULL.
1599                  */
1600                 tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
1601                 head->read_eof = true;
1602         }
1603         return 0;
1604 }
1605
1606 /**
1607  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
1608  *
1609  * @type: Type of interface.
1610  * @file: Pointer to "struct file".
1611  *
1612  * Associates policy handler and returns 0 on success, -ENOMEM otherwise.
1613  *
1614  * Caller acquires tomoyo_read_lock().
1615  */
1616 int tomoyo_open_control(const u8 type, struct file *file)
1617 {
1618         struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
1619
1620         if (!head)
1621                 return -ENOMEM;
1622         mutex_init(&head->io_sem);
1623         head->type = type;
1624         switch (type) {
1625         case TOMOYO_DOMAINPOLICY:
1626                 /* /sys/kernel/security/tomoyo/domain_policy */
1627                 head->write = tomoyo_write_domain_policy;
1628                 head->read = tomoyo_read_domain_policy;
1629                 break;
1630         case TOMOYO_EXCEPTIONPOLICY:
1631                 /* /sys/kernel/security/tomoyo/exception_policy */
1632                 head->write = tomoyo_write_exception_policy;
1633                 head->read = tomoyo_read_exception_policy;
1634                 break;
1635         case TOMOYO_SELFDOMAIN:
1636                 /* /sys/kernel/security/tomoyo/self_domain */
1637                 head->read = tomoyo_read_self_domain;
1638                 break;
1639         case TOMOYO_DOMAIN_STATUS:
1640                 /* /sys/kernel/security/tomoyo/.domain_status */
1641                 head->write = tomoyo_write_domain_profile;
1642                 head->read = tomoyo_read_domain_profile;
1643                 break;
1644         case TOMOYO_PROCESS_STATUS:
1645                 /* /sys/kernel/security/tomoyo/.process_status */
1646                 head->write = tomoyo_write_pid;
1647                 head->read = tomoyo_read_pid;
1648                 break;
1649         case TOMOYO_VERSION:
1650                 /* /sys/kernel/security/tomoyo/version */
1651                 head->read = tomoyo_read_version;
1652                 head->readbuf_size = 128;
1653                 break;
1654         case TOMOYO_MEMINFO:
1655                 /* /sys/kernel/security/tomoyo/meminfo */
1656                 head->write = tomoyo_write_memory_quota;
1657                 head->read = tomoyo_read_memory_counter;
1658                 head->readbuf_size = 512;
1659                 break;
1660         case TOMOYO_PROFILE:
1661                 /* /sys/kernel/security/tomoyo/profile */
1662                 head->write = tomoyo_write_profile;
1663                 head->read = tomoyo_read_profile;
1664                 break;
1665         case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
1666                 head->poll = tomoyo_poll_query;
1667                 head->write = tomoyo_write_answer;
1668                 head->read = tomoyo_read_query;
1669                 break;
1670         case TOMOYO_MANAGER:
1671                 /* /sys/kernel/security/tomoyo/manager */
1672                 head->write = tomoyo_write_manager_policy;
1673                 head->read = tomoyo_read_manager_policy;
1674                 break;
1675         }
1676         if (!(file->f_mode & FMODE_READ)) {
1677                 /*
1678                  * No need to allocate read_buf since it is not opened
1679                  * for reading.
1680                  */
1681                 head->read = NULL;
1682                 head->poll = NULL;
1683         } else if (!head->poll) {
1684                 /* Don't allocate read_buf for poll() access. */
1685                 if (!head->readbuf_size)
1686                         head->readbuf_size = 4096 * 2;
1687                 head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
1688                 if (!head->read_buf) {
1689                         kfree(head);
1690                         return -ENOMEM;
1691                 }
1692         }
1693         if (!(file->f_mode & FMODE_WRITE)) {
1694                 /*
1695                  * No need to allocate write_buf since it is not opened
1696                  * for writing.
1697                  */
1698                 head->write = NULL;
1699         } else if (head->write) {
1700                 head->writebuf_size = 4096 * 2;
1701                 head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
1702                 if (!head->write_buf) {
1703                         kfree(head->read_buf);
1704                         kfree(head);
1705                         return -ENOMEM;
1706                 }
1707         }
1708         if (type != TOMOYO_QUERY)
1709                 head->reader_idx = tomoyo_read_lock();
1710         file->private_data = head;
1711         /*
1712          * Call the handler now if the file is
1713          * /sys/kernel/security/tomoyo/self_domain
1714          * so that the user can use
1715          * cat < /sys/kernel/security/tomoyo/self_domain"
1716          * to know the current process's domainname.
1717          */
1718         if (type == TOMOYO_SELFDOMAIN)
1719                 tomoyo_read_control(file, NULL, 0);
1720         /*
1721          * If the file is /sys/kernel/security/tomoyo/query , increment the
1722          * observer counter.
1723          * The obserber counter is used by tomoyo_supervisor() to see if
1724          * there is some process monitoring /sys/kernel/security/tomoyo/query.
1725          */
1726         else if (type == TOMOYO_QUERY)
1727                 atomic_inc(&tomoyo_query_observers);
1728         return 0;
1729 }
1730
1731 /**
1732  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
1733  *
1734  * @file: Pointer to "struct file".
1735  * @wait: Pointer to "poll_table".
1736  *
1737  * Waits for read readiness.
1738  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd .
1739  */
1740 int tomoyo_poll_control(struct file *file, poll_table *wait)
1741 {
1742         struct tomoyo_io_buffer *head = file->private_data;
1743         if (!head->poll)
1744                 return -ENOSYS;
1745         return head->poll(file, wait);
1746 }
1747
1748 /**
1749  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
1750  *
1751  * @file:       Pointer to "struct file".
1752  * @buffer:     Poiner to buffer to write to.
1753  * @buffer_len: Size of @buffer.
1754  *
1755  * Returns bytes read on success, negative value otherwise.
1756  *
1757  * Caller holds tomoyo_read_lock().
1758  */
1759 int tomoyo_read_control(struct file *file, char __user *buffer,
1760                         const int buffer_len)
1761 {
1762         int len = 0;
1763         struct tomoyo_io_buffer *head = file->private_data;
1764         char *cp;
1765
1766         if (!head->read)
1767                 return -ENOSYS;
1768         if (mutex_lock_interruptible(&head->io_sem))
1769                 return -EINTR;
1770         /* Call the policy handler. */
1771         len = head->read(head);
1772         if (len < 0)
1773                 goto out;
1774         /* Write to buffer. */
1775         len = head->read_avail;
1776         if (len > buffer_len)
1777                 len = buffer_len;
1778         if (!len)
1779                 goto out;
1780         /* head->read_buf changes by some functions. */
1781         cp = head->read_buf;
1782         if (copy_to_user(buffer, cp, len)) {
1783                 len = -EFAULT;
1784                 goto out;
1785         }
1786         head->read_avail -= len;
1787         memmove(cp, cp + len, head->read_avail);
1788  out:
1789         mutex_unlock(&head->io_sem);
1790         return len;
1791 }
1792
1793 /**
1794  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
1795  *
1796  * @file:       Pointer to "struct file".
1797  * @buffer:     Pointer to buffer to read from.
1798  * @buffer_len: Size of @buffer.
1799  *
1800  * Returns @buffer_len on success, negative value otherwise.
1801  *
1802  * Caller holds tomoyo_read_lock().
1803  */
1804 int tomoyo_write_control(struct file *file, const char __user *buffer,
1805                          const int buffer_len)
1806 {
1807         struct tomoyo_io_buffer *head = file->private_data;
1808         int error = buffer_len;
1809         int avail_len = buffer_len;
1810         char *cp0 = head->write_buf;
1811
1812         if (!head->write)
1813                 return -ENOSYS;
1814         if (!access_ok(VERIFY_READ, buffer, buffer_len))
1815                 return -EFAULT;
1816         /* Don't allow updating policies by non manager programs. */
1817         if (head->write != tomoyo_write_pid &&
1818             head->write != tomoyo_write_domain_policy &&
1819             !tomoyo_is_policy_manager())
1820                 return -EPERM;
1821         if (mutex_lock_interruptible(&head->io_sem))
1822                 return -EINTR;
1823         /* Read a line and dispatch it to the policy handler. */
1824         while (avail_len > 0) {
1825                 char c;
1826                 if (head->write_avail >= head->writebuf_size - 1) {
1827                         error = -ENOMEM;
1828                         break;
1829                 } else if (get_user(c, buffer)) {
1830                         error = -EFAULT;
1831                         break;
1832                 }
1833                 buffer++;
1834                 avail_len--;
1835                 cp0[head->write_avail++] = c;
1836                 if (c != '\n')
1837                         continue;
1838                 cp0[head->write_avail - 1] = '\0';
1839                 head->write_avail = 0;
1840                 tomoyo_normalize_line(cp0);
1841                 head->write(head);
1842         }
1843         mutex_unlock(&head->io_sem);
1844         return error;
1845 }
1846
1847 /**
1848  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
1849  *
1850  * @file: Pointer to "struct file".
1851  *
1852  * Releases memory and returns 0.
1853  *
1854  * Caller looses tomoyo_read_lock().
1855  */
1856 int tomoyo_close_control(struct file *file)
1857 {
1858         struct tomoyo_io_buffer *head = file->private_data;
1859         const bool is_write = !!head->write_buf;
1860
1861         /*
1862          * If the file is /sys/kernel/security/tomoyo/query , decrement the
1863          * observer counter.
1864          */
1865         if (head->type == TOMOYO_QUERY)
1866                 atomic_dec(&tomoyo_query_observers);
1867         else
1868                 tomoyo_read_unlock(head->reader_idx);
1869         /* Release memory used for policy I/O. */
1870         kfree(head->read_buf);
1871         head->read_buf = NULL;
1872         kfree(head->write_buf);
1873         head->write_buf = NULL;
1874         kfree(head);
1875         head = NULL;
1876         file->private_data = NULL;
1877         if (is_write)
1878                 tomoyo_run_gc();
1879         return 0;
1880 }
1881
1882 /**
1883  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
1884  */
1885 void tomoyo_check_profile(void)
1886 {
1887         struct tomoyo_domain_info *domain;
1888         const int idx = tomoyo_read_lock();
1889         tomoyo_policy_loaded = true;
1890         /* Check all profiles currently assigned to domains are defined. */
1891         list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
1892                 const u8 profile = domain->profile;
1893                 if (tomoyo_profile_ptr[profile])
1894                         continue;
1895                 panic("Profile %u (used by '%s') not defined.\n",
1896                       profile, domain->domainname->name);
1897         }
1898         tomoyo_read_unlock(idx);
1899         printk(KERN_INFO "TOMOYO: 2.2.0   2009/04/01\n");
1900         printk(KERN_INFO "Mandatory Access Control activated.\n");
1901 }