xref: /linux/security/tomoyo/common.c (revision 60e13231561b3a4c5269bfa1ef6c0569ad6f28ec)
1 /*
2  * security/tomoyo/common.c
3  *
4  * Copyright (C) 2005-2011  NTT DATA CORPORATION
5  */
6 
7 #include <linux/uaccess.h>
8 #include <linux/slab.h>
9 #include <linux/security.h>
10 #include "common.h"
11 
12 /* String table for operation mode. */
13 const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE] = {
14 	[TOMOYO_CONFIG_DISABLED]   = "disabled",
15 	[TOMOYO_CONFIG_LEARNING]   = "learning",
16 	[TOMOYO_CONFIG_PERMISSIVE] = "permissive",
17 	[TOMOYO_CONFIG_ENFORCING]  = "enforcing"
18 };
19 
20 /* String table for /sys/kernel/security/tomoyo/profile */
21 const char * const tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
22 				       + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
23 	[TOMOYO_MAC_FILE_EXECUTE]    = "execute",
24 	[TOMOYO_MAC_FILE_OPEN]       = "open",
25 	[TOMOYO_MAC_FILE_CREATE]     = "create",
26 	[TOMOYO_MAC_FILE_UNLINK]     = "unlink",
27 	[TOMOYO_MAC_FILE_GETATTR]    = "getattr",
28 	[TOMOYO_MAC_FILE_MKDIR]      = "mkdir",
29 	[TOMOYO_MAC_FILE_RMDIR]      = "rmdir",
30 	[TOMOYO_MAC_FILE_MKFIFO]     = "mkfifo",
31 	[TOMOYO_MAC_FILE_MKSOCK]     = "mksock",
32 	[TOMOYO_MAC_FILE_TRUNCATE]   = "truncate",
33 	[TOMOYO_MAC_FILE_SYMLINK]    = "symlink",
34 	[TOMOYO_MAC_FILE_MKBLOCK]    = "mkblock",
35 	[TOMOYO_MAC_FILE_MKCHAR]     = "mkchar",
36 	[TOMOYO_MAC_FILE_LINK]       = "link",
37 	[TOMOYO_MAC_FILE_RENAME]     = "rename",
38 	[TOMOYO_MAC_FILE_CHMOD]      = "chmod",
39 	[TOMOYO_MAC_FILE_CHOWN]      = "chown",
40 	[TOMOYO_MAC_FILE_CHGRP]      = "chgrp",
41 	[TOMOYO_MAC_FILE_IOCTL]      = "ioctl",
42 	[TOMOYO_MAC_FILE_CHROOT]     = "chroot",
43 	[TOMOYO_MAC_FILE_MOUNT]      = "mount",
44 	[TOMOYO_MAC_FILE_UMOUNT]     = "unmount",
45 	[TOMOYO_MAC_FILE_PIVOT_ROOT] = "pivot_root",
46 	[TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
47 };
48 
49 /* String table for conditions. */
50 const char * const tomoyo_condition_keyword[TOMOYO_MAX_CONDITION_KEYWORD] = {
51 	[TOMOYO_TASK_UID]             = "task.uid",
52 	[TOMOYO_TASK_EUID]            = "task.euid",
53 	[TOMOYO_TASK_SUID]            = "task.suid",
54 	[TOMOYO_TASK_FSUID]           = "task.fsuid",
55 	[TOMOYO_TASK_GID]             = "task.gid",
56 	[TOMOYO_TASK_EGID]            = "task.egid",
57 	[TOMOYO_TASK_SGID]            = "task.sgid",
58 	[TOMOYO_TASK_FSGID]           = "task.fsgid",
59 	[TOMOYO_TASK_PID]             = "task.pid",
60 	[TOMOYO_TASK_PPID]            = "task.ppid",
61 	[TOMOYO_EXEC_ARGC]            = "exec.argc",
62 	[TOMOYO_EXEC_ENVC]            = "exec.envc",
63 	[TOMOYO_TYPE_IS_SOCKET]       = "socket",
64 	[TOMOYO_TYPE_IS_SYMLINK]      = "symlink",
65 	[TOMOYO_TYPE_IS_FILE]         = "file",
66 	[TOMOYO_TYPE_IS_BLOCK_DEV]    = "block",
67 	[TOMOYO_TYPE_IS_DIRECTORY]    = "directory",
68 	[TOMOYO_TYPE_IS_CHAR_DEV]     = "char",
69 	[TOMOYO_TYPE_IS_FIFO]         = "fifo",
70 	[TOMOYO_MODE_SETUID]          = "setuid",
71 	[TOMOYO_MODE_SETGID]          = "setgid",
72 	[TOMOYO_MODE_STICKY]          = "sticky",
73 	[TOMOYO_MODE_OWNER_READ]      = "owner_read",
74 	[TOMOYO_MODE_OWNER_WRITE]     = "owner_write",
75 	[TOMOYO_MODE_OWNER_EXECUTE]   = "owner_execute",
76 	[TOMOYO_MODE_GROUP_READ]      = "group_read",
77 	[TOMOYO_MODE_GROUP_WRITE]     = "group_write",
78 	[TOMOYO_MODE_GROUP_EXECUTE]   = "group_execute",
79 	[TOMOYO_MODE_OTHERS_READ]     = "others_read",
80 	[TOMOYO_MODE_OTHERS_WRITE]    = "others_write",
81 	[TOMOYO_MODE_OTHERS_EXECUTE]  = "others_execute",
82 	[TOMOYO_EXEC_REALPATH]        = "exec.realpath",
83 	[TOMOYO_SYMLINK_TARGET]       = "symlink.target",
84 	[TOMOYO_PATH1_UID]            = "path1.uid",
85 	[TOMOYO_PATH1_GID]            = "path1.gid",
86 	[TOMOYO_PATH1_INO]            = "path1.ino",
87 	[TOMOYO_PATH1_MAJOR]          = "path1.major",
88 	[TOMOYO_PATH1_MINOR]          = "path1.minor",
89 	[TOMOYO_PATH1_PERM]           = "path1.perm",
90 	[TOMOYO_PATH1_TYPE]           = "path1.type",
91 	[TOMOYO_PATH1_DEV_MAJOR]      = "path1.dev_major",
92 	[TOMOYO_PATH1_DEV_MINOR]      = "path1.dev_minor",
93 	[TOMOYO_PATH2_UID]            = "path2.uid",
94 	[TOMOYO_PATH2_GID]            = "path2.gid",
95 	[TOMOYO_PATH2_INO]            = "path2.ino",
96 	[TOMOYO_PATH2_MAJOR]          = "path2.major",
97 	[TOMOYO_PATH2_MINOR]          = "path2.minor",
98 	[TOMOYO_PATH2_PERM]           = "path2.perm",
99 	[TOMOYO_PATH2_TYPE]           = "path2.type",
100 	[TOMOYO_PATH2_DEV_MAJOR]      = "path2.dev_major",
101 	[TOMOYO_PATH2_DEV_MINOR]      = "path2.dev_minor",
102 	[TOMOYO_PATH1_PARENT_UID]     = "path1.parent.uid",
103 	[TOMOYO_PATH1_PARENT_GID]     = "path1.parent.gid",
104 	[TOMOYO_PATH1_PARENT_INO]     = "path1.parent.ino",
105 	[TOMOYO_PATH1_PARENT_PERM]    = "path1.parent.perm",
106 	[TOMOYO_PATH2_PARENT_UID]     = "path2.parent.uid",
107 	[TOMOYO_PATH2_PARENT_GID]     = "path2.parent.gid",
108 	[TOMOYO_PATH2_PARENT_INO]     = "path2.parent.ino",
109 	[TOMOYO_PATH2_PARENT_PERM]    = "path2.parent.perm",
110 };
111 
112 /* String table for PREFERENCE keyword. */
113 static const char * const tomoyo_pref_keywords[TOMOYO_MAX_PREF] = {
114 	[TOMOYO_PREF_MAX_AUDIT_LOG]      = "max_audit_log",
115 	[TOMOYO_PREF_MAX_LEARNING_ENTRY] = "max_learning_entry",
116 };
117 
118 /* String table for path operation. */
119 const char * const tomoyo_path_keyword[TOMOYO_MAX_PATH_OPERATION] = {
120 	[TOMOYO_TYPE_EXECUTE]    = "execute",
121 	[TOMOYO_TYPE_READ]       = "read",
122 	[TOMOYO_TYPE_WRITE]      = "write",
123 	[TOMOYO_TYPE_APPEND]     = "append",
124 	[TOMOYO_TYPE_UNLINK]     = "unlink",
125 	[TOMOYO_TYPE_GETATTR]    = "getattr",
126 	[TOMOYO_TYPE_RMDIR]      = "rmdir",
127 	[TOMOYO_TYPE_TRUNCATE]   = "truncate",
128 	[TOMOYO_TYPE_SYMLINK]    = "symlink",
129 	[TOMOYO_TYPE_CHROOT]     = "chroot",
130 	[TOMOYO_TYPE_UMOUNT]     = "unmount",
131 };
132 
133 /* String table for categories. */
134 static const char * const tomoyo_category_keywords
135 [TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
136 	[TOMOYO_MAC_CATEGORY_FILE]       = "file",
137 };
138 
139 /* Permit policy management by non-root user? */
140 static bool tomoyo_manage_by_non_root;
141 
142 /* Utility functions. */
143 
144 /**
145  * tomoyo_yesno - Return "yes" or "no".
146  *
147  * @value: Bool value.
148  */
149 const char *tomoyo_yesno(const unsigned int value)
150 {
151 	return value ? "yes" : "no";
152 }
153 
154 /**
155  * tomoyo_addprintf - strncat()-like-snprintf().
156  *
157  * @buffer: Buffer to write to. Must be '\0'-terminated.
158  * @len:    Size of @buffer.
159  * @fmt:    The printf()'s format string, followed by parameters.
160  *
161  * Returns nothing.
162  */
163 static void tomoyo_addprintf(char *buffer, int len, const char *fmt, ...)
164 {
165 	va_list args;
166 	const int pos = strlen(buffer);
167 	va_start(args, fmt);
168 	vsnprintf(buffer + pos, len - pos - 1, fmt, args);
169 	va_end(args);
170 }
171 
172 /**
173  * tomoyo_flush - Flush queued string to userspace's buffer.
174  *
175  * @head:   Pointer to "struct tomoyo_io_buffer".
176  *
177  * Returns true if all data was flushed, false otherwise.
178  */
179 static bool tomoyo_flush(struct tomoyo_io_buffer *head)
180 {
181 	while (head->r.w_pos) {
182 		const char *w = head->r.w[0];
183 		size_t len = strlen(w);
184 		if (len) {
185 			if (len > head->read_user_buf_avail)
186 				len = head->read_user_buf_avail;
187 			if (!len)
188 				return false;
189 			if (copy_to_user(head->read_user_buf, w, len))
190 				return false;
191 			head->read_user_buf_avail -= len;
192 			head->read_user_buf += len;
193 			w += len;
194 		}
195 		head->r.w[0] = w;
196 		if (*w)
197 			return false;
198 		/* Add '\0' for audit logs and query. */
199 		if (head->poll) {
200 			if (!head->read_user_buf_avail ||
201 			    copy_to_user(head->read_user_buf, "", 1))
202 				return false;
203 			head->read_user_buf_avail--;
204 			head->read_user_buf++;
205 		}
206 		head->r.w_pos--;
207 		for (len = 0; len < head->r.w_pos; len++)
208 			head->r.w[len] = head->r.w[len + 1];
209 	}
210 	head->r.avail = 0;
211 	return true;
212 }
213 
214 /**
215  * tomoyo_set_string - Queue string to "struct tomoyo_io_buffer" structure.
216  *
217  * @head:   Pointer to "struct tomoyo_io_buffer".
218  * @string: String to print.
219  *
220  * Note that @string has to be kept valid until @head is kfree()d.
221  * This means that char[] allocated on stack memory cannot be passed to
222  * this function. Use tomoyo_io_printf() for char[] allocated on stack memory.
223  */
224 static void tomoyo_set_string(struct tomoyo_io_buffer *head, const char *string)
225 {
226 	if (head->r.w_pos < TOMOYO_MAX_IO_READ_QUEUE) {
227 		head->r.w[head->r.w_pos++] = string;
228 		tomoyo_flush(head);
229 	} else
230 		WARN_ON(1);
231 }
232 
233 /**
234  * tomoyo_io_printf - printf() to "struct tomoyo_io_buffer" structure.
235  *
236  * @head: Pointer to "struct tomoyo_io_buffer".
237  * @fmt:  The printf()'s format string, followed by parameters.
238  */
239 void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt, ...)
240 {
241 	va_list args;
242 	size_t len;
243 	size_t pos = head->r.avail;
244 	int size = head->readbuf_size - pos;
245 	if (size <= 0)
246 		return;
247 	va_start(args, fmt);
248 	len = vsnprintf(head->read_buf + pos, size, fmt, args) + 1;
249 	va_end(args);
250 	if (pos + len >= head->readbuf_size) {
251 		WARN_ON(1);
252 		return;
253 	}
254 	head->r.avail += len;
255 	tomoyo_set_string(head, head->read_buf + pos);
256 }
257 
258 /**
259  * tomoyo_set_space - Put a space to "struct tomoyo_io_buffer" structure.
260  *
261  * @head: Pointer to "struct tomoyo_io_buffer".
262  *
263  * Returns nothing.
264  */
265 static void tomoyo_set_space(struct tomoyo_io_buffer *head)
266 {
267 	tomoyo_set_string(head, " ");
268 }
269 
270 /**
271  * tomoyo_set_lf - Put a line feed to "struct tomoyo_io_buffer" structure.
272  *
273  * @head: Pointer to "struct tomoyo_io_buffer".
274  *
275  * Returns nothing.
276  */
277 static bool tomoyo_set_lf(struct tomoyo_io_buffer *head)
278 {
279 	tomoyo_set_string(head, "\n");
280 	return !head->r.w_pos;
281 }
282 
283 /**
284  * tomoyo_set_slash - Put a shash to "struct tomoyo_io_buffer" structure.
285  *
286  * @head: Pointer to "struct tomoyo_io_buffer".
287  *
288  * Returns nothing.
289  */
290 static void tomoyo_set_slash(struct tomoyo_io_buffer *head)
291 {
292 	tomoyo_set_string(head, "/");
293 }
294 
295 /* List of namespaces. */
296 LIST_HEAD(tomoyo_namespace_list);
297 /* True if namespace other than tomoyo_kernel_namespace is defined. */
298 static bool tomoyo_namespace_enabled;
299 
300 /**
301  * tomoyo_init_policy_namespace - Initialize namespace.
302  *
303  * @ns: Pointer to "struct tomoyo_policy_namespace".
304  *
305  * Returns nothing.
306  */
307 void tomoyo_init_policy_namespace(struct tomoyo_policy_namespace *ns)
308 {
309 	unsigned int idx;
310 	for (idx = 0; idx < TOMOYO_MAX_ACL_GROUPS; idx++)
311 		INIT_LIST_HEAD(&ns->acl_group[idx]);
312 	for (idx = 0; idx < TOMOYO_MAX_GROUP; idx++)
313 		INIT_LIST_HEAD(&ns->group_list[idx]);
314 	for (idx = 0; idx < TOMOYO_MAX_POLICY; idx++)
315 		INIT_LIST_HEAD(&ns->policy_list[idx]);
316 	ns->profile_version = 20100903;
317 	tomoyo_namespace_enabled = !list_empty(&tomoyo_namespace_list);
318 	list_add_tail_rcu(&ns->namespace_list, &tomoyo_namespace_list);
319 }
320 
321 /**
322  * tomoyo_print_namespace - Print namespace header.
323  *
324  * @head: Pointer to "struct tomoyo_io_buffer".
325  *
326  * Returns nothing.
327  */
328 static void tomoyo_print_namespace(struct tomoyo_io_buffer *head)
329 {
330 	if (!tomoyo_namespace_enabled)
331 		return;
332 	tomoyo_set_string(head,
333 			  container_of(head->r.ns,
334 				       struct tomoyo_policy_namespace,
335 				       namespace_list)->name);
336 	tomoyo_set_space(head);
337 }
338 
339 /**
340  * tomoyo_print_name_union - Print a tomoyo_name_union.
341  *
342  * @head: Pointer to "struct tomoyo_io_buffer".
343  * @ptr:  Pointer to "struct tomoyo_name_union".
344  */
345 static void tomoyo_print_name_union(struct tomoyo_io_buffer *head,
346 				    const struct tomoyo_name_union *ptr)
347 {
348 	tomoyo_set_space(head);
349 	if (ptr->group) {
350 		tomoyo_set_string(head, "@");
351 		tomoyo_set_string(head, ptr->group->group_name->name);
352 	} else {
353 		tomoyo_set_string(head, ptr->filename->name);
354 	}
355 }
356 
357 /**
358  * tomoyo_print_name_union_quoted - Print a tomoyo_name_union with a quote.
359  *
360  * @head: Pointer to "struct tomoyo_io_buffer".
361  * @ptr:  Pointer to "struct tomoyo_name_union".
362  *
363  * Returns nothing.
364  */
365 static void tomoyo_print_name_union_quoted(struct tomoyo_io_buffer *head,
366 					   const struct tomoyo_name_union *ptr)
367 {
368 	if (ptr->group) {
369 		tomoyo_set_string(head, "@");
370 		tomoyo_set_string(head, ptr->group->group_name->name);
371 	} else {
372 		tomoyo_set_string(head, "\"");
373 		tomoyo_set_string(head, ptr->filename->name);
374 		tomoyo_set_string(head, "\"");
375 	}
376 }
377 
378 /**
379  * tomoyo_print_number_union_nospace - Print a tomoyo_number_union without a space.
380  *
381  * @head: Pointer to "struct tomoyo_io_buffer".
382  * @ptr:  Pointer to "struct tomoyo_number_union".
383  *
384  * Returns nothing.
385  */
386 static void tomoyo_print_number_union_nospace
387 (struct tomoyo_io_buffer *head, const struct tomoyo_number_union *ptr)
388 {
389 	if (ptr->group) {
390 		tomoyo_set_string(head, "@");
391 		tomoyo_set_string(head, ptr->group->group_name->name);
392 	} else {
393 		int i;
394 		unsigned long min = ptr->values[0];
395 		const unsigned long max = ptr->values[1];
396 		u8 min_type = ptr->value_type[0];
397 		const u8 max_type = ptr->value_type[1];
398 		char buffer[128];
399 		buffer[0] = '\0';
400 		for (i = 0; i < 2; i++) {
401 			switch (min_type) {
402 			case TOMOYO_VALUE_TYPE_HEXADECIMAL:
403 				tomoyo_addprintf(buffer, sizeof(buffer),
404 						 "0x%lX", min);
405 				break;
406 			case TOMOYO_VALUE_TYPE_OCTAL:
407 				tomoyo_addprintf(buffer, sizeof(buffer),
408 						 "0%lo", min);
409 				break;
410 			default:
411 				tomoyo_addprintf(buffer, sizeof(buffer), "%lu",
412 						 min);
413 				break;
414 			}
415 			if (min == max && min_type == max_type)
416 				break;
417 			tomoyo_addprintf(buffer, sizeof(buffer), "-");
418 			min_type = max_type;
419 			min = max;
420 		}
421 		tomoyo_io_printf(head, "%s", buffer);
422 	}
423 }
424 
425 /**
426  * tomoyo_print_number_union - Print a tomoyo_number_union.
427  *
428  * @head: Pointer to "struct tomoyo_io_buffer".
429  * @ptr:  Pointer to "struct tomoyo_number_union".
430  *
431  * Returns nothing.
432  */
433 static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
434 				      const struct tomoyo_number_union *ptr)
435 {
436 	tomoyo_set_space(head);
437 	tomoyo_print_number_union_nospace(head, ptr);
438 }
439 
440 /**
441  * tomoyo_assign_profile - Create a new profile.
442  *
443  * @ns:      Pointer to "struct tomoyo_policy_namespace".
444  * @profile: Profile number to create.
445  *
446  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
447  */
448 static struct tomoyo_profile *tomoyo_assign_profile
449 (struct tomoyo_policy_namespace *ns, const unsigned int profile)
450 {
451 	struct tomoyo_profile *ptr;
452 	struct tomoyo_profile *entry;
453 	if (profile >= TOMOYO_MAX_PROFILES)
454 		return NULL;
455 	ptr = ns->profile_ptr[profile];
456 	if (ptr)
457 		return ptr;
458 	entry = kzalloc(sizeof(*entry), GFP_NOFS);
459 	if (mutex_lock_interruptible(&tomoyo_policy_lock))
460 		goto out;
461 	ptr = ns->profile_ptr[profile];
462 	if (!ptr && tomoyo_memory_ok(entry)) {
463 		ptr = entry;
464 		ptr->default_config = TOMOYO_CONFIG_DISABLED |
465 			TOMOYO_CONFIG_WANT_GRANT_LOG |
466 			TOMOYO_CONFIG_WANT_REJECT_LOG;
467 		memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
468 		       sizeof(ptr->config));
469 		ptr->pref[TOMOYO_PREF_MAX_AUDIT_LOG] = 1024;
470 		ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] = 2048;
471 		mb(); /* Avoid out-of-order execution. */
472 		ns->profile_ptr[profile] = ptr;
473 		entry = NULL;
474 	}
475 	mutex_unlock(&tomoyo_policy_lock);
476  out:
477 	kfree(entry);
478 	return ptr;
479 }
480 
481 /**
482  * tomoyo_profile - Find a profile.
483  *
484  * @ns:      Pointer to "struct tomoyo_policy_namespace".
485  * @profile: Profile number to find.
486  *
487  * Returns pointer to "struct tomoyo_profile".
488  */
489 struct tomoyo_profile *tomoyo_profile(const struct tomoyo_policy_namespace *ns,
490 				      const u8 profile)
491 {
492 	static struct tomoyo_profile tomoyo_null_profile;
493 	struct tomoyo_profile *ptr = ns->profile_ptr[profile];
494 	if (!ptr)
495 		ptr = &tomoyo_null_profile;
496 	return ptr;
497 }
498 
499 /**
500  * tomoyo_find_yesno - Find values for specified keyword.
501  *
502  * @string: String to check.
503  * @find:   Name of keyword.
504  *
505  * Returns 1 if "@find=yes" was found, 0 if "@find=no" was found, -1 otherwise.
506  */
507 static s8 tomoyo_find_yesno(const char *string, const char *find)
508 {
509 	const char *cp = strstr(string, find);
510 	if (cp) {
511 		cp += strlen(find);
512 		if (!strncmp(cp, "=yes", 4))
513 			return 1;
514 		else if (!strncmp(cp, "=no", 3))
515 			return 0;
516 	}
517 	return -1;
518 }
519 
520 /**
521  * tomoyo_set_uint - Set value for specified preference.
522  *
523  * @i:      Pointer to "unsigned int".
524  * @string: String to check.
525  * @find:   Name of keyword.
526  *
527  * Returns nothing.
528  */
529 static void tomoyo_set_uint(unsigned int *i, const char *string,
530 			    const char *find)
531 {
532 	const char *cp = strstr(string, find);
533 	if (cp)
534 		sscanf(cp + strlen(find), "=%u", i);
535 }
536 
537 /**
538  * tomoyo_set_mode - Set mode for specified profile.
539  *
540  * @name:    Name of functionality.
541  * @value:   Mode for @name.
542  * @profile: Pointer to "struct tomoyo_profile".
543  *
544  * Returns 0 on success, negative value otherwise.
545  */
546 static int tomoyo_set_mode(char *name, const char *value,
547 			   struct tomoyo_profile *profile)
548 {
549 	u8 i;
550 	u8 config;
551 	if (!strcmp(name, "CONFIG")) {
552 		i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
553 		config = profile->default_config;
554 	} else if (tomoyo_str_starts(&name, "CONFIG::")) {
555 		config = 0;
556 		for (i = 0; i < TOMOYO_MAX_MAC_INDEX
557 			     + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
558 			int len = 0;
559 			if (i < TOMOYO_MAX_MAC_INDEX) {
560 				const u8 c = tomoyo_index2category[i];
561 				const char *category =
562 					tomoyo_category_keywords[c];
563 				len = strlen(category);
564 				if (strncmp(name, category, len) ||
565 				    name[len++] != ':' || name[len++] != ':')
566 					continue;
567 			}
568 			if (strcmp(name + len, tomoyo_mac_keywords[i]))
569 				continue;
570 			config = profile->config[i];
571 			break;
572 		}
573 		if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
574 			return -EINVAL;
575 	} else {
576 		return -EINVAL;
577 	}
578 	if (strstr(value, "use_default")) {
579 		config = TOMOYO_CONFIG_USE_DEFAULT;
580 	} else {
581 		u8 mode;
582 		for (mode = 0; mode < 4; mode++)
583 			if (strstr(value, tomoyo_mode[mode]))
584 				/*
585 				 * Update lower 3 bits in order to distinguish
586 				 * 'config' from 'TOMOYO_CONFIG_USE_DEAFULT'.
587 				 */
588 				config = (config & ~7) | mode;
589 		if (config != TOMOYO_CONFIG_USE_DEFAULT) {
590 			switch (tomoyo_find_yesno(value, "grant_log")) {
591 			case 1:
592 				config |= TOMOYO_CONFIG_WANT_GRANT_LOG;
593 				break;
594 			case 0:
595 				config &= ~TOMOYO_CONFIG_WANT_GRANT_LOG;
596 				break;
597 			}
598 			switch (tomoyo_find_yesno(value, "reject_log")) {
599 			case 1:
600 				config |= TOMOYO_CONFIG_WANT_REJECT_LOG;
601 				break;
602 			case 0:
603 				config &= ~TOMOYO_CONFIG_WANT_REJECT_LOG;
604 				break;
605 			}
606 		}
607 	}
608 	if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
609 		profile->config[i] = config;
610 	else if (config != TOMOYO_CONFIG_USE_DEFAULT)
611 		profile->default_config = config;
612 	return 0;
613 }
614 
615 /**
616  * tomoyo_write_profile - Write profile table.
617  *
618  * @head: Pointer to "struct tomoyo_io_buffer".
619  *
620  * Returns 0 on success, negative value otherwise.
621  */
622 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
623 {
624 	char *data = head->write_buf;
625 	unsigned int i;
626 	char *cp;
627 	struct tomoyo_profile *profile;
628 	if (sscanf(data, "PROFILE_VERSION=%u", &head->w.ns->profile_version)
629 	    == 1)
630 		return 0;
631 	i = simple_strtoul(data, &cp, 10);
632 	if (*cp != '-')
633 		return -EINVAL;
634 	data = cp + 1;
635 	profile = tomoyo_assign_profile(head->w.ns, i);
636 	if (!profile)
637 		return -EINVAL;
638 	cp = strchr(data, '=');
639 	if (!cp)
640 		return -EINVAL;
641 	*cp++ = '\0';
642 	if (!strcmp(data, "COMMENT")) {
643 		static DEFINE_SPINLOCK(lock);
644 		const struct tomoyo_path_info *new_comment
645 			= tomoyo_get_name(cp);
646 		const struct tomoyo_path_info *old_comment;
647 		if (!new_comment)
648 			return -ENOMEM;
649 		spin_lock(&lock);
650 		old_comment = profile->comment;
651 		profile->comment = new_comment;
652 		spin_unlock(&lock);
653 		tomoyo_put_name(old_comment);
654 		return 0;
655 	}
656 	if (!strcmp(data, "PREFERENCE")) {
657 		for (i = 0; i < TOMOYO_MAX_PREF; i++)
658 			tomoyo_set_uint(&profile->pref[i], cp,
659 					tomoyo_pref_keywords[i]);
660 		return 0;
661 	}
662 	return tomoyo_set_mode(data, cp, profile);
663 }
664 
665 /**
666  * tomoyo_print_config - Print mode for specified functionality.
667  *
668  * @head:   Pointer to "struct tomoyo_io_buffer".
669  * @config: Mode for that functionality.
670  *
671  * Returns nothing.
672  *
673  * Caller prints functionality's name.
674  */
675 static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
676 {
677 	tomoyo_io_printf(head, "={ mode=%s grant_log=%s reject_log=%s }\n",
678 			 tomoyo_mode[config & 3],
679 			 tomoyo_yesno(config & TOMOYO_CONFIG_WANT_GRANT_LOG),
680 			 tomoyo_yesno(config & TOMOYO_CONFIG_WANT_REJECT_LOG));
681 }
682 
683 /**
684  * tomoyo_read_profile - Read profile table.
685  *
686  * @head: Pointer to "struct tomoyo_io_buffer".
687  *
688  * Returns nothing.
689  */
690 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
691 {
692 	u8 index;
693 	struct tomoyo_policy_namespace *ns =
694 		container_of(head->r.ns, typeof(*ns), namespace_list);
695 	const struct tomoyo_profile *profile;
696 	if (head->r.eof)
697 		return;
698  next:
699 	index = head->r.index;
700 	profile = ns->profile_ptr[index];
701 	switch (head->r.step) {
702 	case 0:
703 		tomoyo_print_namespace(head);
704 		tomoyo_io_printf(head, "PROFILE_VERSION=%u\n",
705 				 ns->profile_version);
706 		head->r.step++;
707 		break;
708 	case 1:
709 		for ( ; head->r.index < TOMOYO_MAX_PROFILES;
710 		      head->r.index++)
711 			if (ns->profile_ptr[head->r.index])
712 				break;
713 		if (head->r.index == TOMOYO_MAX_PROFILES) {
714 			head->r.eof = true;
715 			return;
716 		}
717 		head->r.step++;
718 		break;
719 	case 2:
720 		{
721 			u8 i;
722 			const struct tomoyo_path_info *comment =
723 				profile->comment;
724 			tomoyo_print_namespace(head);
725 			tomoyo_io_printf(head, "%u-COMMENT=", index);
726 			tomoyo_set_string(head, comment ? comment->name : "");
727 			tomoyo_set_lf(head);
728 			tomoyo_print_namespace(head);
729 			tomoyo_io_printf(head, "%u-PREFERENCE={ ", index);
730 			for (i = 0; i < TOMOYO_MAX_PREF; i++)
731 				tomoyo_io_printf(head, "%s=%u ",
732 						 tomoyo_pref_keywords[i],
733 						 profile->pref[i]);
734 			tomoyo_set_string(head, "}\n");
735 			head->r.step++;
736 		}
737 		break;
738 	case 3:
739 		{
740 			tomoyo_print_namespace(head);
741 			tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
742 			tomoyo_print_config(head, profile->default_config);
743 			head->r.bit = 0;
744 			head->r.step++;
745 		}
746 		break;
747 	case 4:
748 		for ( ; head->r.bit < TOMOYO_MAX_MAC_INDEX
749 			      + TOMOYO_MAX_MAC_CATEGORY_INDEX; head->r.bit++) {
750 			const u8 i = head->r.bit;
751 			const u8 config = profile->config[i];
752 			if (config == TOMOYO_CONFIG_USE_DEFAULT)
753 				continue;
754 			tomoyo_print_namespace(head);
755 			if (i < TOMOYO_MAX_MAC_INDEX)
756 				tomoyo_io_printf(head, "%u-CONFIG::%s::%s",
757 						 index,
758 						 tomoyo_category_keywords
759 						 [tomoyo_index2category[i]],
760 						 tomoyo_mac_keywords[i]);
761 			else
762 				tomoyo_io_printf(head, "%u-CONFIG::%s", index,
763 						 tomoyo_mac_keywords[i]);
764 			tomoyo_print_config(head, config);
765 			head->r.bit++;
766 			break;
767 		}
768 		if (head->r.bit == TOMOYO_MAX_MAC_INDEX
769 		    + TOMOYO_MAX_MAC_CATEGORY_INDEX) {
770 			head->r.index++;
771 			head->r.step = 1;
772 		}
773 		break;
774 	}
775 	if (tomoyo_flush(head))
776 		goto next;
777 }
778 
779 /**
780  * tomoyo_same_manager - Check for duplicated "struct tomoyo_manager" entry.
781  *
782  * @a: Pointer to "struct tomoyo_acl_head".
783  * @b: Pointer to "struct tomoyo_acl_head".
784  *
785  * Returns true if @a == @b, false otherwise.
786  */
787 static bool tomoyo_same_manager(const struct tomoyo_acl_head *a,
788 				const struct tomoyo_acl_head *b)
789 {
790 	return container_of(a, struct tomoyo_manager, head)->manager ==
791 		container_of(b, struct tomoyo_manager, head)->manager;
792 }
793 
794 /**
795  * tomoyo_update_manager_entry - Add a manager entry.
796  *
797  * @manager:   The path to manager or the domainnamme.
798  * @is_delete: True if it is a delete request.
799  *
800  * Returns 0 on success, negative value otherwise.
801  *
802  * Caller holds tomoyo_read_lock().
803  */
804 static int tomoyo_update_manager_entry(const char *manager,
805 				       const bool is_delete)
806 {
807 	struct tomoyo_manager e = { };
808 	struct tomoyo_acl_param param = {
809 		/* .ns = &tomoyo_kernel_namespace, */
810 		.is_delete = is_delete,
811 		.list = &tomoyo_kernel_namespace.
812 		policy_list[TOMOYO_ID_MANAGER],
813 	};
814 	int error = is_delete ? -ENOENT : -ENOMEM;
815 	if (tomoyo_domain_def(manager)) {
816 		if (!tomoyo_correct_domain(manager))
817 			return -EINVAL;
818 		e.is_domain = true;
819 	} else {
820 		if (!tomoyo_correct_path(manager))
821 			return -EINVAL;
822 	}
823 	e.manager = tomoyo_get_name(manager);
824 	if (e.manager) {
825 		error = tomoyo_update_policy(&e.head, sizeof(e), &param,
826 					     tomoyo_same_manager);
827 		tomoyo_put_name(e.manager);
828 	}
829 	return error;
830 }
831 
832 /**
833  * tomoyo_write_manager - Write manager policy.
834  *
835  * @head: Pointer to "struct tomoyo_io_buffer".
836  *
837  * Returns 0 on success, negative value otherwise.
838  *
839  * Caller holds tomoyo_read_lock().
840  */
841 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
842 {
843 	char *data = head->write_buf;
844 
845 	if (!strcmp(data, "manage_by_non_root")) {
846 		tomoyo_manage_by_non_root = !head->w.is_delete;
847 		return 0;
848 	}
849 	return tomoyo_update_manager_entry(data, head->w.is_delete);
850 }
851 
852 /**
853  * tomoyo_read_manager - Read manager policy.
854  *
855  * @head: Pointer to "struct tomoyo_io_buffer".
856  *
857  * Caller holds tomoyo_read_lock().
858  */
859 static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
860 {
861 	if (head->r.eof)
862 		return;
863 	list_for_each_cookie(head->r.acl, &tomoyo_kernel_namespace.
864 			     policy_list[TOMOYO_ID_MANAGER]) {
865 		struct tomoyo_manager *ptr =
866 			list_entry(head->r.acl, typeof(*ptr), head.list);
867 		if (ptr->head.is_deleted)
868 			continue;
869 		if (!tomoyo_flush(head))
870 			return;
871 		tomoyo_set_string(head, ptr->manager->name);
872 		tomoyo_set_lf(head);
873 	}
874 	head->r.eof = true;
875 }
876 
877 /**
878  * tomoyo_manager - Check whether the current process is a policy manager.
879  *
880  * Returns true if the current process is permitted to modify policy
881  * via /sys/kernel/security/tomoyo/ interface.
882  *
883  * Caller holds tomoyo_read_lock().
884  */
885 static bool tomoyo_manager(void)
886 {
887 	struct tomoyo_manager *ptr;
888 	const char *exe;
889 	const struct task_struct *task = current;
890 	const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
891 	bool found = false;
892 
893 	if (!tomoyo_policy_loaded)
894 		return true;
895 	if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
896 		return false;
897 	list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
898 				policy_list[TOMOYO_ID_MANAGER], head.list) {
899 		if (!ptr->head.is_deleted && ptr->is_domain
900 		    && !tomoyo_pathcmp(domainname, ptr->manager)) {
901 			found = true;
902 			break;
903 		}
904 	}
905 	if (found)
906 		return true;
907 	exe = tomoyo_get_exe();
908 	if (!exe)
909 		return false;
910 	list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
911 				policy_list[TOMOYO_ID_MANAGER], head.list) {
912 		if (!ptr->head.is_deleted && !ptr->is_domain
913 		    && !strcmp(exe, ptr->manager->name)) {
914 			found = true;
915 			break;
916 		}
917 	}
918 	if (!found) { /* Reduce error messages. */
919 		static pid_t last_pid;
920 		const pid_t pid = current->pid;
921 		if (last_pid != pid) {
922 			printk(KERN_WARNING "%s ( %s ) is not permitted to "
923 			       "update policies.\n", domainname->name, exe);
924 			last_pid = pid;
925 		}
926 	}
927 	kfree(exe);
928 	return found;
929 }
930 
931 /**
932  * tomoyo_select_domain - Parse select command.
933  *
934  * @head: Pointer to "struct tomoyo_io_buffer".
935  * @data: String to parse.
936  *
937  * Returns true on success, false otherwise.
938  *
939  * Caller holds tomoyo_read_lock().
940  */
941 static bool tomoyo_select_domain(struct tomoyo_io_buffer *head,
942 				 const char *data)
943 {
944 	unsigned int pid;
945 	struct tomoyo_domain_info *domain = NULL;
946 	bool global_pid = false;
947 	if (strncmp(data, "select ", 7))
948 		return false;
949 	data += 7;
950 	if (sscanf(data, "pid=%u", &pid) == 1 ||
951 	    (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
952 		struct task_struct *p;
953 		rcu_read_lock();
954 		read_lock(&tasklist_lock);
955 		if (global_pid)
956 			p = find_task_by_pid_ns(pid, &init_pid_ns);
957 		else
958 			p = find_task_by_vpid(pid);
959 		if (p)
960 			domain = tomoyo_real_domain(p);
961 		read_unlock(&tasklist_lock);
962 		rcu_read_unlock();
963 	} else if (!strncmp(data, "domain=", 7)) {
964 		if (tomoyo_domain_def(data + 7))
965 			domain = tomoyo_find_domain(data + 7);
966 	} else
967 		return false;
968 	head->w.domain = domain;
969 	/* Accessing read_buf is safe because head->io_sem is held. */
970 	if (!head->read_buf)
971 		return true; /* Do nothing if open(O_WRONLY). */
972 	memset(&head->r, 0, sizeof(head->r));
973 	head->r.print_this_domain_only = true;
974 	if (domain)
975 		head->r.domain = &domain->list;
976 	else
977 		head->r.eof = 1;
978 	tomoyo_io_printf(head, "# select %s\n", data);
979 	if (domain && domain->is_deleted)
980 		tomoyo_io_printf(head, "# This is a deleted domain.\n");
981 	return true;
982 }
983 
984 /**
985  * tomoyo_delete_domain - Delete a domain.
986  *
987  * @domainname: The name of domain.
988  *
989  * Returns 0.
990  *
991  * Caller holds tomoyo_read_lock().
992  */
993 static int tomoyo_delete_domain(char *domainname)
994 {
995 	struct tomoyo_domain_info *domain;
996 	struct tomoyo_path_info name;
997 
998 	name.name = domainname;
999 	tomoyo_fill_path_info(&name);
1000 	if (mutex_lock_interruptible(&tomoyo_policy_lock))
1001 		return 0;
1002 	/* Is there an active domain? */
1003 	list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
1004 		/* Never delete tomoyo_kernel_domain */
1005 		if (domain == &tomoyo_kernel_domain)
1006 			continue;
1007 		if (domain->is_deleted ||
1008 		    tomoyo_pathcmp(domain->domainname, &name))
1009 			continue;
1010 		domain->is_deleted = true;
1011 		break;
1012 	}
1013 	mutex_unlock(&tomoyo_policy_lock);
1014 	return 0;
1015 }
1016 
1017 /**
1018  * tomoyo_write_domain2 - Write domain policy.
1019  *
1020  * @ns:        Pointer to "struct tomoyo_policy_namespace".
1021  * @list:      Pointer to "struct list_head".
1022  * @data:      Policy to be interpreted.
1023  * @is_delete: True if it is a delete request.
1024  *
1025  * Returns 0 on success, negative value otherwise.
1026  *
1027  * Caller holds tomoyo_read_lock().
1028  */
1029 static int tomoyo_write_domain2(struct tomoyo_policy_namespace *ns,
1030 				struct list_head *list, char *data,
1031 				const bool is_delete)
1032 {
1033 	struct tomoyo_acl_param param = {
1034 		.ns = ns,
1035 		.list = list,
1036 		.data = data,
1037 		.is_delete = is_delete,
1038 	};
1039 	static const struct {
1040 		const char *keyword;
1041 		int (*write) (struct tomoyo_acl_param *);
1042 	} tomoyo_callback[1] = {
1043 		{ "file ", tomoyo_write_file },
1044 	};
1045 	u8 i;
1046 	for (i = 0; i < 1; i++) {
1047 		if (!tomoyo_str_starts(&param.data,
1048 				       tomoyo_callback[i].keyword))
1049 			continue;
1050 		return tomoyo_callback[i].write(&param);
1051 	}
1052 	return -EINVAL;
1053 }
1054 
1055 /* String table for domain flags. */
1056 const char * const tomoyo_dif[TOMOYO_MAX_DOMAIN_INFO_FLAGS] = {
1057 	[TOMOYO_DIF_QUOTA_WARNED]      = "quota_exceeded\n",
1058 	[TOMOYO_DIF_TRANSITION_FAILED] = "transition_failed\n",
1059 };
1060 
1061 /**
1062  * tomoyo_write_domain - Write domain policy.
1063  *
1064  * @head: Pointer to "struct tomoyo_io_buffer".
1065  *
1066  * Returns 0 on success, negative value otherwise.
1067  *
1068  * Caller holds tomoyo_read_lock().
1069  */
1070 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
1071 {
1072 	char *data = head->write_buf;
1073 	struct tomoyo_policy_namespace *ns;
1074 	struct tomoyo_domain_info *domain = head->w.domain;
1075 	const bool is_delete = head->w.is_delete;
1076 	bool is_select = !is_delete && tomoyo_str_starts(&data, "select ");
1077 	unsigned int profile;
1078 	if (*data == '<') {
1079 		domain = NULL;
1080 		if (is_delete)
1081 			tomoyo_delete_domain(data);
1082 		else if (is_select)
1083 			domain = tomoyo_find_domain(data);
1084 		else
1085 			domain = tomoyo_assign_domain(data, false);
1086 		head->w.domain = domain;
1087 		return 0;
1088 	}
1089 	if (!domain)
1090 		return -EINVAL;
1091 	ns = domain->ns;
1092 	if (sscanf(data, "use_profile %u", &profile) == 1
1093 	    && profile < TOMOYO_MAX_PROFILES) {
1094 		if (!tomoyo_policy_loaded || ns->profile_ptr[profile])
1095 			domain->profile = (u8) profile;
1096 		return 0;
1097 	}
1098 	if (sscanf(data, "use_group %u\n", &profile) == 1
1099 	    && profile < TOMOYO_MAX_ACL_GROUPS) {
1100 		if (!is_delete)
1101 			domain->group = (u8) profile;
1102 		return 0;
1103 	}
1104 	for (profile = 0; profile < TOMOYO_MAX_DOMAIN_INFO_FLAGS; profile++) {
1105 		const char *cp = tomoyo_dif[profile];
1106 		if (strncmp(data, cp, strlen(cp) - 1))
1107 			continue;
1108 		domain->flags[profile] = !is_delete;
1109 		return 0;
1110 	}
1111 	return tomoyo_write_domain2(ns, &domain->acl_info_list, data,
1112 				    is_delete);
1113 }
1114 
1115 /**
1116  * tomoyo_print_condition - Print condition part.
1117  *
1118  * @head: Pointer to "struct tomoyo_io_buffer".
1119  * @cond: Pointer to "struct tomoyo_condition".
1120  *
1121  * Returns true on success, false otherwise.
1122  */
1123 static bool tomoyo_print_condition(struct tomoyo_io_buffer *head,
1124 				   const struct tomoyo_condition *cond)
1125 {
1126 	switch (head->r.cond_step) {
1127 	case 0:
1128 		head->r.cond_index = 0;
1129 		head->r.cond_step++;
1130 		/* fall through */
1131 	case 1:
1132 		{
1133 			const u16 condc = cond->condc;
1134 			const struct tomoyo_condition_element *condp =
1135 				(typeof(condp)) (cond + 1);
1136 			const struct tomoyo_number_union *numbers_p =
1137 				(typeof(numbers_p)) (condp + condc);
1138 			const struct tomoyo_name_union *names_p =
1139 				(typeof(names_p))
1140 				(numbers_p + cond->numbers_count);
1141 			const struct tomoyo_argv *argv =
1142 				(typeof(argv)) (names_p + cond->names_count);
1143 			const struct tomoyo_envp *envp =
1144 				(typeof(envp)) (argv + cond->argc);
1145 			u16 skip;
1146 			for (skip = 0; skip < head->r.cond_index; skip++) {
1147 				const u8 left = condp->left;
1148 				const u8 right = condp->right;
1149 				condp++;
1150 				switch (left) {
1151 				case TOMOYO_ARGV_ENTRY:
1152 					argv++;
1153 					continue;
1154 				case TOMOYO_ENVP_ENTRY:
1155 					envp++;
1156 					continue;
1157 				case TOMOYO_NUMBER_UNION:
1158 					numbers_p++;
1159 					break;
1160 				}
1161 				switch (right) {
1162 				case TOMOYO_NAME_UNION:
1163 					names_p++;
1164 					break;
1165 				case TOMOYO_NUMBER_UNION:
1166 					numbers_p++;
1167 					break;
1168 				}
1169 			}
1170 			while (head->r.cond_index < condc) {
1171 				const u8 match = condp->equals;
1172 				const u8 left = condp->left;
1173 				const u8 right = condp->right;
1174 				if (!tomoyo_flush(head))
1175 					return false;
1176 				condp++;
1177 				head->r.cond_index++;
1178 				tomoyo_set_space(head);
1179 				switch (left) {
1180 				case TOMOYO_ARGV_ENTRY:
1181 					tomoyo_io_printf(head,
1182 							 "exec.argv[%lu]%s=\"",
1183 							 argv->index, argv->
1184 							 is_not ? "!" : "");
1185 					tomoyo_set_string(head,
1186 							  argv->value->name);
1187 					tomoyo_set_string(head, "\"");
1188 					argv++;
1189 					continue;
1190 				case TOMOYO_ENVP_ENTRY:
1191 					tomoyo_set_string(head,
1192 							  "exec.envp[\"");
1193 					tomoyo_set_string(head,
1194 							  envp->name->name);
1195 					tomoyo_io_printf(head, "\"]%s=", envp->
1196 							 is_not ? "!" : "");
1197 					if (envp->value) {
1198 						tomoyo_set_string(head, "\"");
1199 						tomoyo_set_string(head, envp->
1200 								  value->name);
1201 						tomoyo_set_string(head, "\"");
1202 					} else {
1203 						tomoyo_set_string(head,
1204 								  "NULL");
1205 					}
1206 					envp++;
1207 					continue;
1208 				case TOMOYO_NUMBER_UNION:
1209 					tomoyo_print_number_union_nospace
1210 						(head, numbers_p++);
1211 					break;
1212 				default:
1213 					tomoyo_set_string(head,
1214 					       tomoyo_condition_keyword[left]);
1215 					break;
1216 				}
1217 				tomoyo_set_string(head, match ? "=" : "!=");
1218 				switch (right) {
1219 				case TOMOYO_NAME_UNION:
1220 					tomoyo_print_name_union_quoted
1221 						(head, names_p++);
1222 					break;
1223 				case TOMOYO_NUMBER_UNION:
1224 					tomoyo_print_number_union_nospace
1225 						(head, numbers_p++);
1226 					break;
1227 				default:
1228 					tomoyo_set_string(head,
1229 					  tomoyo_condition_keyword[right]);
1230 					break;
1231 				}
1232 			}
1233 		}
1234 		head->r.cond_step++;
1235 		/* fall through */
1236 	case 2:
1237 		if (!tomoyo_flush(head))
1238 			break;
1239 		head->r.cond_step++;
1240 		/* fall through */
1241 	case 3:
1242 		tomoyo_set_lf(head);
1243 		return true;
1244 	}
1245 	return false;
1246 }
1247 
1248 /**
1249  * tomoyo_set_group - Print "acl_group " header keyword and category name.
1250  *
1251  * @head:     Pointer to "struct tomoyo_io_buffer".
1252  * @category: Category name.
1253  *
1254  * Returns nothing.
1255  */
1256 static void tomoyo_set_group(struct tomoyo_io_buffer *head,
1257 			     const char *category)
1258 {
1259 	if (head->type == TOMOYO_EXCEPTIONPOLICY) {
1260 		tomoyo_print_namespace(head);
1261 		tomoyo_io_printf(head, "acl_group %u ",
1262 				 head->r.acl_group_index);
1263 	}
1264 	tomoyo_set_string(head, category);
1265 }
1266 
1267 /**
1268  * tomoyo_print_entry - Print an ACL entry.
1269  *
1270  * @head: Pointer to "struct tomoyo_io_buffer".
1271  * @acl:  Pointer to an ACL entry.
1272  *
1273  * Returns true on success, false otherwise.
1274  */
1275 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
1276 			       struct tomoyo_acl_info *acl)
1277 {
1278 	const u8 acl_type = acl->type;
1279 	bool first = true;
1280 	u8 bit;
1281 
1282 	if (head->r.print_cond_part)
1283 		goto print_cond_part;
1284 	if (acl->is_deleted)
1285 		return true;
1286 	if (!tomoyo_flush(head))
1287 		return false;
1288 	else if (acl_type == TOMOYO_TYPE_PATH_ACL) {
1289 		struct tomoyo_path_acl *ptr =
1290 			container_of(acl, typeof(*ptr), head);
1291 		const u16 perm = ptr->perm;
1292 		for (bit = 0; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
1293 			if (!(perm & (1 << bit)))
1294 				continue;
1295 			if (head->r.print_transition_related_only &&
1296 			    bit != TOMOYO_TYPE_EXECUTE)
1297 				continue;
1298 			if (first) {
1299 				tomoyo_set_group(head, "file ");
1300 				first = false;
1301 			} else {
1302 				tomoyo_set_slash(head);
1303 			}
1304 			tomoyo_set_string(head, tomoyo_path_keyword[bit]);
1305 		}
1306 		if (first)
1307 			return true;
1308 		tomoyo_print_name_union(head, &ptr->name);
1309 	} else if (head->r.print_transition_related_only) {
1310 		return true;
1311 	} else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
1312 		struct tomoyo_path2_acl *ptr =
1313 			container_of(acl, typeof(*ptr), head);
1314 		const u8 perm = ptr->perm;
1315 		for (bit = 0; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
1316 			if (!(perm & (1 << bit)))
1317 				continue;
1318 			if (first) {
1319 				tomoyo_set_group(head, "file ");
1320 				first = false;
1321 			} else {
1322 				tomoyo_set_slash(head);
1323 			}
1324 			tomoyo_set_string(head, tomoyo_mac_keywords
1325 					  [tomoyo_pp2mac[bit]]);
1326 		}
1327 		if (first)
1328 			return true;
1329 		tomoyo_print_name_union(head, &ptr->name1);
1330 		tomoyo_print_name_union(head, &ptr->name2);
1331 	} else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
1332 		struct tomoyo_path_number_acl *ptr =
1333 			container_of(acl, typeof(*ptr), head);
1334 		const u8 perm = ptr->perm;
1335 		for (bit = 0; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION; bit++) {
1336 			if (!(perm & (1 << bit)))
1337 				continue;
1338 			if (first) {
1339 				tomoyo_set_group(head, "file ");
1340 				first = false;
1341 			} else {
1342 				tomoyo_set_slash(head);
1343 			}
1344 			tomoyo_set_string(head, tomoyo_mac_keywords
1345 					  [tomoyo_pn2mac[bit]]);
1346 		}
1347 		if (first)
1348 			return true;
1349 		tomoyo_print_name_union(head, &ptr->name);
1350 		tomoyo_print_number_union(head, &ptr->number);
1351 	} else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
1352 		struct tomoyo_mkdev_acl *ptr =
1353 			container_of(acl, typeof(*ptr), head);
1354 		const u8 perm = ptr->perm;
1355 		for (bit = 0; bit < TOMOYO_MAX_MKDEV_OPERATION; bit++) {
1356 			if (!(perm & (1 << bit)))
1357 				continue;
1358 			if (first) {
1359 				tomoyo_set_group(head, "file ");
1360 				first = false;
1361 			} else {
1362 				tomoyo_set_slash(head);
1363 			}
1364 			tomoyo_set_string(head, tomoyo_mac_keywords
1365 					  [tomoyo_pnnn2mac[bit]]);
1366 		}
1367 		if (first)
1368 			return true;
1369 		tomoyo_print_name_union(head, &ptr->name);
1370 		tomoyo_print_number_union(head, &ptr->mode);
1371 		tomoyo_print_number_union(head, &ptr->major);
1372 		tomoyo_print_number_union(head, &ptr->minor);
1373 	} else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
1374 		struct tomoyo_mount_acl *ptr =
1375 			container_of(acl, typeof(*ptr), head);
1376 		tomoyo_set_group(head, "file mount");
1377 		tomoyo_print_name_union(head, &ptr->dev_name);
1378 		tomoyo_print_name_union(head, &ptr->dir_name);
1379 		tomoyo_print_name_union(head, &ptr->fs_type);
1380 		tomoyo_print_number_union(head, &ptr->flags);
1381 	}
1382 	if (acl->cond) {
1383 		head->r.print_cond_part = true;
1384 		head->r.cond_step = 0;
1385 		if (!tomoyo_flush(head))
1386 			return false;
1387 print_cond_part:
1388 		if (!tomoyo_print_condition(head, acl->cond))
1389 			return false;
1390 		head->r.print_cond_part = false;
1391 	} else {
1392 		tomoyo_set_lf(head);
1393 	}
1394 	return true;
1395 }
1396 
1397 /**
1398  * tomoyo_read_domain2 - Read domain policy.
1399  *
1400  * @head: Pointer to "struct tomoyo_io_buffer".
1401  * @list: Pointer to "struct list_head".
1402  *
1403  * Caller holds tomoyo_read_lock().
1404  *
1405  * Returns true on success, false otherwise.
1406  */
1407 static bool tomoyo_read_domain2(struct tomoyo_io_buffer *head,
1408 				struct list_head *list)
1409 {
1410 	list_for_each_cookie(head->r.acl, list) {
1411 		struct tomoyo_acl_info *ptr =
1412 			list_entry(head->r.acl, typeof(*ptr), list);
1413 		if (!tomoyo_print_entry(head, ptr))
1414 			return false;
1415 	}
1416 	head->r.acl = NULL;
1417 	return true;
1418 }
1419 
1420 /**
1421  * tomoyo_read_domain - Read domain policy.
1422  *
1423  * @head: Pointer to "struct tomoyo_io_buffer".
1424  *
1425  * Caller holds tomoyo_read_lock().
1426  */
1427 static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
1428 {
1429 	if (head->r.eof)
1430 		return;
1431 	list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1432 		struct tomoyo_domain_info *domain =
1433 			list_entry(head->r.domain, typeof(*domain), list);
1434 		switch (head->r.step) {
1435 			u8 i;
1436 		case 0:
1437 			if (domain->is_deleted &&
1438 			    !head->r.print_this_domain_only)
1439 				continue;
1440 			/* Print domainname and flags. */
1441 			tomoyo_set_string(head, domain->domainname->name);
1442 			tomoyo_set_lf(head);
1443 			tomoyo_io_printf(head, "use_profile %u\n",
1444 					 domain->profile);
1445 			tomoyo_io_printf(head, "use_group %u\n",
1446 					 domain->group);
1447 			for (i = 0; i < TOMOYO_MAX_DOMAIN_INFO_FLAGS; i++)
1448 				if (domain->flags[i])
1449 					tomoyo_set_string(head, tomoyo_dif[i]);
1450 			head->r.step++;
1451 			tomoyo_set_lf(head);
1452 			/* fall through */
1453 		case 1:
1454 			if (!tomoyo_read_domain2(head, &domain->acl_info_list))
1455 				return;
1456 			head->r.step++;
1457 			if (!tomoyo_set_lf(head))
1458 				return;
1459 			/* fall through */
1460 		case 2:
1461 			head->r.step = 0;
1462 			if (head->r.print_this_domain_only)
1463 				goto done;
1464 		}
1465 	}
1466  done:
1467 	head->r.eof = true;
1468 }
1469 
1470 /**
1471  * tomoyo_write_pid: Specify PID to obtain domainname.
1472  *
1473  * @head: Pointer to "struct tomoyo_io_buffer".
1474  *
1475  * Returns 0.
1476  */
1477 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1478 {
1479 	head->r.eof = false;
1480 	return 0;
1481 }
1482 
1483 /**
1484  * tomoyo_read_pid - Get domainname of the specified PID.
1485  *
1486  * @head: Pointer to "struct tomoyo_io_buffer".
1487  *
1488  * Returns the domainname which the specified PID is in on success,
1489  * empty string otherwise.
1490  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1491  * using read()/write() interface rather than sysctl() interface.
1492  */
1493 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1494 {
1495 	char *buf = head->write_buf;
1496 	bool global_pid = false;
1497 	unsigned int pid;
1498 	struct task_struct *p;
1499 	struct tomoyo_domain_info *domain = NULL;
1500 
1501 	/* Accessing write_buf is safe because head->io_sem is held. */
1502 	if (!buf) {
1503 		head->r.eof = true;
1504 		return; /* Do nothing if open(O_RDONLY). */
1505 	}
1506 	if (head->r.w_pos || head->r.eof)
1507 		return;
1508 	head->r.eof = true;
1509 	if (tomoyo_str_starts(&buf, "global-pid "))
1510 		global_pid = true;
1511 	pid = (unsigned int) simple_strtoul(buf, NULL, 10);
1512 	rcu_read_lock();
1513 	read_lock(&tasklist_lock);
1514 	if (global_pid)
1515 		p = find_task_by_pid_ns(pid, &init_pid_ns);
1516 	else
1517 		p = find_task_by_vpid(pid);
1518 	if (p)
1519 		domain = tomoyo_real_domain(p);
1520 	read_unlock(&tasklist_lock);
1521 	rcu_read_unlock();
1522 	if (!domain)
1523 		return;
1524 	tomoyo_io_printf(head, "%u %u ", pid, domain->profile);
1525 	tomoyo_set_string(head, domain->domainname->name);
1526 }
1527 
1528 /* String table for domain transition control keywords. */
1529 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1530 	[TOMOYO_TRANSITION_CONTROL_NO_RESET]      = "no_reset_domain ",
1531 	[TOMOYO_TRANSITION_CONTROL_RESET]         = "reset_domain ",
1532 	[TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain ",
1533 	[TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain ",
1534 	[TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain ",
1535 	[TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain ",
1536 };
1537 
1538 /* String table for grouping keywords. */
1539 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1540 	[TOMOYO_PATH_GROUP]   = "path_group ",
1541 	[TOMOYO_NUMBER_GROUP] = "number_group ",
1542 };
1543 
1544 /**
1545  * tomoyo_write_exception - Write exception policy.
1546  *
1547  * @head: Pointer to "struct tomoyo_io_buffer".
1548  *
1549  * Returns 0 on success, negative value otherwise.
1550  *
1551  * Caller holds tomoyo_read_lock().
1552  */
1553 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
1554 {
1555 	const bool is_delete = head->w.is_delete;
1556 	struct tomoyo_acl_param param = {
1557 		.ns = head->w.ns,
1558 		.is_delete = is_delete,
1559 		.data = head->write_buf,
1560 	};
1561 	u8 i;
1562 	if (tomoyo_str_starts(&param.data, "aggregator "))
1563 		return tomoyo_write_aggregator(&param);
1564 	for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
1565 		if (tomoyo_str_starts(&param.data, tomoyo_transition_type[i]))
1566 			return tomoyo_write_transition_control(&param, i);
1567 	for (i = 0; i < TOMOYO_MAX_GROUP; i++)
1568 		if (tomoyo_str_starts(&param.data, tomoyo_group_name[i]))
1569 			return tomoyo_write_group(&param, i);
1570 	if (tomoyo_str_starts(&param.data, "acl_group ")) {
1571 		unsigned int group;
1572 		char *data;
1573 		group = simple_strtoul(param.data, &data, 10);
1574 		if (group < TOMOYO_MAX_ACL_GROUPS && *data++ == ' ')
1575 			return tomoyo_write_domain2
1576 				(head->w.ns, &head->w.ns->acl_group[group],
1577 				 data, is_delete);
1578 	}
1579 	return -EINVAL;
1580 }
1581 
1582 /**
1583  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group" list.
1584  *
1585  * @head: Pointer to "struct tomoyo_io_buffer".
1586  * @idx:  Index number.
1587  *
1588  * Returns true on success, false otherwise.
1589  *
1590  * Caller holds tomoyo_read_lock().
1591  */
1592 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1593 {
1594 	struct tomoyo_policy_namespace *ns =
1595 		container_of(head->r.ns, typeof(*ns), namespace_list);
1596 	struct list_head *list = &ns->group_list[idx];
1597 	list_for_each_cookie(head->r.group, list) {
1598 		struct tomoyo_group *group =
1599 			list_entry(head->r.group, typeof(*group), head.list);
1600 		list_for_each_cookie(head->r.acl, &group->member_list) {
1601 			struct tomoyo_acl_head *ptr =
1602 				list_entry(head->r.acl, typeof(*ptr), list);
1603 			if (ptr->is_deleted)
1604 				continue;
1605 			if (!tomoyo_flush(head))
1606 				return false;
1607 			tomoyo_print_namespace(head);
1608 			tomoyo_set_string(head, tomoyo_group_name[idx]);
1609 			tomoyo_set_string(head, group->group_name->name);
1610 			if (idx == TOMOYO_PATH_GROUP) {
1611 				tomoyo_set_space(head);
1612 				tomoyo_set_string(head, container_of
1613 					       (ptr, struct tomoyo_path_group,
1614 						head)->member_name->name);
1615 			} else if (idx == TOMOYO_NUMBER_GROUP) {
1616 				tomoyo_print_number_union(head, &container_of
1617 							  (ptr,
1618 						   struct tomoyo_number_group,
1619 							   head)->number);
1620 			}
1621 			tomoyo_set_lf(head);
1622 		}
1623 		head->r.acl = NULL;
1624 	}
1625 	head->r.group = NULL;
1626 	return true;
1627 }
1628 
1629 /**
1630  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1631  *
1632  * @head: Pointer to "struct tomoyo_io_buffer".
1633  * @idx:  Index number.
1634  *
1635  * Returns true on success, false otherwise.
1636  *
1637  * Caller holds tomoyo_read_lock().
1638  */
1639 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1640 {
1641 	struct tomoyo_policy_namespace *ns =
1642 		container_of(head->r.ns, typeof(*ns), namespace_list);
1643 	struct list_head *list = &ns->policy_list[idx];
1644 	list_for_each_cookie(head->r.acl, list) {
1645 		struct tomoyo_acl_head *acl =
1646 			container_of(head->r.acl, typeof(*acl), list);
1647 		if (acl->is_deleted)
1648 			continue;
1649 		if (!tomoyo_flush(head))
1650 			return false;
1651 		switch (idx) {
1652 		case TOMOYO_ID_TRANSITION_CONTROL:
1653 			{
1654 				struct tomoyo_transition_control *ptr =
1655 					container_of(acl, typeof(*ptr), head);
1656 				tomoyo_print_namespace(head);
1657 				tomoyo_set_string(head, tomoyo_transition_type
1658 						  [ptr->type]);
1659 				tomoyo_set_string(head, ptr->program ?
1660 						  ptr->program->name : "any");
1661 				tomoyo_set_string(head, " from ");
1662 				tomoyo_set_string(head, ptr->domainname ?
1663 						  ptr->domainname->name :
1664 						  "any");
1665 			}
1666 			break;
1667 		case TOMOYO_ID_AGGREGATOR:
1668 			{
1669 				struct tomoyo_aggregator *ptr =
1670 					container_of(acl, typeof(*ptr), head);
1671 				tomoyo_print_namespace(head);
1672 				tomoyo_set_string(head, "aggregator ");
1673 				tomoyo_set_string(head,
1674 						  ptr->original_name->name);
1675 				tomoyo_set_space(head);
1676 				tomoyo_set_string(head,
1677 					       ptr->aggregated_name->name);
1678 			}
1679 			break;
1680 		default:
1681 			continue;
1682 		}
1683 		tomoyo_set_lf(head);
1684 	}
1685 	head->r.acl = NULL;
1686 	return true;
1687 }
1688 
1689 /**
1690  * tomoyo_read_exception - Read exception policy.
1691  *
1692  * @head: Pointer to "struct tomoyo_io_buffer".
1693  *
1694  * Caller holds tomoyo_read_lock().
1695  */
1696 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
1697 {
1698 	struct tomoyo_policy_namespace *ns =
1699 		container_of(head->r.ns, typeof(*ns), namespace_list);
1700 	if (head->r.eof)
1701 		return;
1702 	while (head->r.step < TOMOYO_MAX_POLICY &&
1703 	       tomoyo_read_policy(head, head->r.step))
1704 		head->r.step++;
1705 	if (head->r.step < TOMOYO_MAX_POLICY)
1706 		return;
1707 	while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1708 	       tomoyo_read_group(head, head->r.step - TOMOYO_MAX_POLICY))
1709 		head->r.step++;
1710 	if (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1711 		return;
1712 	while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP
1713 	       + TOMOYO_MAX_ACL_GROUPS) {
1714 		head->r.acl_group_index = head->r.step - TOMOYO_MAX_POLICY
1715 			- TOMOYO_MAX_GROUP;
1716 		if (!tomoyo_read_domain2(head, &ns->acl_group
1717 					 [head->r.acl_group_index]))
1718 			return;
1719 		head->r.step++;
1720 	}
1721 	head->r.eof = true;
1722 }
1723 
1724 /* Wait queue for kernel -> userspace notification. */
1725 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1726 /* Wait queue for userspace -> kernel notification. */
1727 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_answer_wait);
1728 
1729 /* Structure for query. */
1730 struct tomoyo_query {
1731 	struct list_head list;
1732 	char *query;
1733 	size_t query_len;
1734 	unsigned int serial;
1735 	u8 timer;
1736 	u8 answer;
1737 	u8 retry;
1738 };
1739 
1740 /* The list for "struct tomoyo_query". */
1741 static LIST_HEAD(tomoyo_query_list);
1742 
1743 /* Lock for manipulating tomoyo_query_list. */
1744 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1745 
1746 /*
1747  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1748  * interface.
1749  */
1750 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1751 
1752 /**
1753  * tomoyo_truncate - Truncate a line.
1754  *
1755  * @str: String to truncate.
1756  *
1757  * Returns length of truncated @str.
1758  */
1759 static int tomoyo_truncate(char *str)
1760 {
1761 	char *start = str;
1762 	while (*(unsigned char *) str > (unsigned char) ' ')
1763 		str++;
1764 	*str = '\0';
1765 	return strlen(start) + 1;
1766 }
1767 
1768 /**
1769  * tomoyo_add_entry - Add an ACL to current thread's domain. Used by learning mode.
1770  *
1771  * @domain: Pointer to "struct tomoyo_domain_info".
1772  * @header: Lines containing ACL.
1773  *
1774  * Returns nothing.
1775  */
1776 static void tomoyo_add_entry(struct tomoyo_domain_info *domain, char *header)
1777 {
1778 	char *buffer;
1779 	char *realpath = NULL;
1780 	char *argv0 = NULL;
1781 	char *symlink = NULL;
1782 	char *cp = strchr(header, '\n');
1783 	int len;
1784 	if (!cp)
1785 		return;
1786 	cp = strchr(cp + 1, '\n');
1787 	if (!cp)
1788 		return;
1789 	*cp++ = '\0';
1790 	len = strlen(cp) + 1;
1791 	/* strstr() will return NULL if ordering is wrong. */
1792 	if (*cp == 'f') {
1793 		argv0 = strstr(header, " argv[]={ \"");
1794 		if (argv0) {
1795 			argv0 += 10;
1796 			len += tomoyo_truncate(argv0) + 14;
1797 		}
1798 		realpath = strstr(header, " exec={ realpath=\"");
1799 		if (realpath) {
1800 			realpath += 8;
1801 			len += tomoyo_truncate(realpath) + 6;
1802 		}
1803 		symlink = strstr(header, " symlink.target=\"");
1804 		if (symlink)
1805 			len += tomoyo_truncate(symlink + 1) + 1;
1806 	}
1807 	buffer = kmalloc(len, GFP_NOFS);
1808 	if (!buffer)
1809 		return;
1810 	snprintf(buffer, len - 1, "%s", cp);
1811 	if (realpath)
1812 		tomoyo_addprintf(buffer, len, " exec.%s", realpath);
1813 	if (argv0)
1814 		tomoyo_addprintf(buffer, len, " exec.argv[0]=%s", argv0);
1815 	if (symlink)
1816 		tomoyo_addprintf(buffer, len, "%s", symlink);
1817 	tomoyo_normalize_line(buffer);
1818 	if (!tomoyo_write_domain2(domain->ns, &domain->acl_info_list, buffer,
1819 				  false))
1820 		tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
1821 	kfree(buffer);
1822 }
1823 
1824 /**
1825  * tomoyo_supervisor - Ask for the supervisor's decision.
1826  *
1827  * @r:   Pointer to "struct tomoyo_request_info".
1828  * @fmt: The printf()'s format string, followed by parameters.
1829  *
1830  * Returns 0 if the supervisor decided to permit the access request which
1831  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
1832  * supervisor decided to retry the access request which violated the policy in
1833  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
1834  */
1835 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
1836 {
1837 	va_list args;
1838 	int error;
1839 	int len;
1840 	static unsigned int tomoyo_serial;
1841 	struct tomoyo_query entry = { };
1842 	bool quota_exceeded = false;
1843 	va_start(args, fmt);
1844 	len = vsnprintf((char *) &len, 1, fmt, args) + 1;
1845 	va_end(args);
1846 	/* Write /sys/kernel/security/tomoyo/audit. */
1847 	va_start(args, fmt);
1848 	tomoyo_write_log2(r, len, fmt, args);
1849 	va_end(args);
1850 	/* Nothing more to do if granted. */
1851 	if (r->granted)
1852 		return 0;
1853 	if (r->mode)
1854 		tomoyo_update_stat(r->mode);
1855 	switch (r->mode) {
1856 	case TOMOYO_CONFIG_ENFORCING:
1857 		error = -EPERM;
1858 		if (atomic_read(&tomoyo_query_observers))
1859 			break;
1860 		goto out;
1861 	case TOMOYO_CONFIG_LEARNING:
1862 		error = 0;
1863 		/* Check max_learning_entry parameter. */
1864 		if (tomoyo_domain_quota_is_ok(r))
1865 			break;
1866 		/* fall through */
1867 	default:
1868 		return 0;
1869 	}
1870 	/* Get message. */
1871 	va_start(args, fmt);
1872 	entry.query = tomoyo_init_log(r, len, fmt, args);
1873 	va_end(args);
1874 	if (!entry.query)
1875 		goto out;
1876 	entry.query_len = strlen(entry.query) + 1;
1877 	if (!error) {
1878 		tomoyo_add_entry(r->domain, entry.query);
1879 		goto out;
1880 	}
1881 	len = tomoyo_round2(entry.query_len);
1882 	spin_lock(&tomoyo_query_list_lock);
1883 	if (tomoyo_memory_quota[TOMOYO_MEMORY_QUERY] &&
1884 	    tomoyo_memory_used[TOMOYO_MEMORY_QUERY] + len
1885 	    >= tomoyo_memory_quota[TOMOYO_MEMORY_QUERY]) {
1886 		quota_exceeded = true;
1887 	} else {
1888 		entry.serial = tomoyo_serial++;
1889 		entry.retry = r->retry;
1890 		tomoyo_memory_used[TOMOYO_MEMORY_QUERY] += len;
1891 		list_add_tail(&entry.list, &tomoyo_query_list);
1892 	}
1893 	spin_unlock(&tomoyo_query_list_lock);
1894 	if (quota_exceeded)
1895 		goto out;
1896 	/* Give 10 seconds for supervisor's opinion. */
1897 	while (entry.timer < 10) {
1898 		wake_up_all(&tomoyo_query_wait);
1899 		if (wait_event_interruptible_timeout
1900 		    (tomoyo_answer_wait, entry.answer ||
1901 		     !atomic_read(&tomoyo_query_observers), HZ))
1902 			break;
1903 		else
1904 			entry.timer++;
1905 	}
1906 	spin_lock(&tomoyo_query_list_lock);
1907 	list_del(&entry.list);
1908 	tomoyo_memory_used[TOMOYO_MEMORY_QUERY] -= len;
1909 	spin_unlock(&tomoyo_query_list_lock);
1910 	switch (entry.answer) {
1911 	case 3: /* Asked to retry by administrator. */
1912 		error = TOMOYO_RETRY_REQUEST;
1913 		r->retry++;
1914 		break;
1915 	case 1:
1916 		/* Granted by administrator. */
1917 		error = 0;
1918 		break;
1919 	default:
1920 		/* Timed out or rejected by administrator. */
1921 		break;
1922 	}
1923 out:
1924 	kfree(entry.query);
1925 	return error;
1926 }
1927 
1928 /**
1929  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
1930  *
1931  * @file: Pointer to "struct file".
1932  * @wait: Pointer to "poll_table".
1933  *
1934  * Returns POLLIN | POLLRDNORM when ready to read, 0 otherwise.
1935  *
1936  * Waits for access requests which violated policy in enforcing mode.
1937  */
1938 static int tomoyo_poll_query(struct file *file, poll_table *wait)
1939 {
1940 	struct list_head *tmp;
1941 	bool found = false;
1942 	u8 i;
1943 	for (i = 0; i < 2; i++) {
1944 		spin_lock(&tomoyo_query_list_lock);
1945 		list_for_each(tmp, &tomoyo_query_list) {
1946 			struct tomoyo_query *ptr =
1947 				list_entry(tmp, typeof(*ptr), list);
1948 			if (ptr->answer)
1949 				continue;
1950 			found = true;
1951 			break;
1952 		}
1953 		spin_unlock(&tomoyo_query_list_lock);
1954 		if (found)
1955 			return POLLIN | POLLRDNORM;
1956 		if (i)
1957 			break;
1958 		poll_wait(file, &tomoyo_query_wait, wait);
1959 	}
1960 	return 0;
1961 }
1962 
1963 /**
1964  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
1965  *
1966  * @head: Pointer to "struct tomoyo_io_buffer".
1967  */
1968 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
1969 {
1970 	struct list_head *tmp;
1971 	unsigned int pos = 0;
1972 	size_t len = 0;
1973 	char *buf;
1974 	if (head->r.w_pos)
1975 		return;
1976 	if (head->read_buf) {
1977 		kfree(head->read_buf);
1978 		head->read_buf = NULL;
1979 	}
1980 	spin_lock(&tomoyo_query_list_lock);
1981 	list_for_each(tmp, &tomoyo_query_list) {
1982 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
1983 		if (ptr->answer)
1984 			continue;
1985 		if (pos++ != head->r.query_index)
1986 			continue;
1987 		len = ptr->query_len;
1988 		break;
1989 	}
1990 	spin_unlock(&tomoyo_query_list_lock);
1991 	if (!len) {
1992 		head->r.query_index = 0;
1993 		return;
1994 	}
1995 	buf = kzalloc(len + 32, GFP_NOFS);
1996 	if (!buf)
1997 		return;
1998 	pos = 0;
1999 	spin_lock(&tomoyo_query_list_lock);
2000 	list_for_each(tmp, &tomoyo_query_list) {
2001 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2002 		if (ptr->answer)
2003 			continue;
2004 		if (pos++ != head->r.query_index)
2005 			continue;
2006 		/*
2007 		 * Some query can be skipped because tomoyo_query_list
2008 		 * can change, but I don't care.
2009 		 */
2010 		if (len == ptr->query_len)
2011 			snprintf(buf, len + 31, "Q%u-%hu\n%s", ptr->serial,
2012 				 ptr->retry, ptr->query);
2013 		break;
2014 	}
2015 	spin_unlock(&tomoyo_query_list_lock);
2016 	if (buf[0]) {
2017 		head->read_buf = buf;
2018 		head->r.w[head->r.w_pos++] = buf;
2019 		head->r.query_index++;
2020 	} else {
2021 		kfree(buf);
2022 	}
2023 }
2024 
2025 /**
2026  * tomoyo_write_answer - Write the supervisor's decision.
2027  *
2028  * @head: Pointer to "struct tomoyo_io_buffer".
2029  *
2030  * Returns 0 on success, -EINVAL otherwise.
2031  */
2032 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
2033 {
2034 	char *data = head->write_buf;
2035 	struct list_head *tmp;
2036 	unsigned int serial;
2037 	unsigned int answer;
2038 	spin_lock(&tomoyo_query_list_lock);
2039 	list_for_each(tmp, &tomoyo_query_list) {
2040 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2041 		ptr->timer = 0;
2042 	}
2043 	spin_unlock(&tomoyo_query_list_lock);
2044 	if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
2045 		return -EINVAL;
2046 	spin_lock(&tomoyo_query_list_lock);
2047 	list_for_each(tmp, &tomoyo_query_list) {
2048 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2049 		if (ptr->serial != serial)
2050 			continue;
2051 		if (!ptr->answer)
2052 			ptr->answer = answer;
2053 		break;
2054 	}
2055 	spin_unlock(&tomoyo_query_list_lock);
2056 	return 0;
2057 }
2058 
2059 /**
2060  * tomoyo_read_version: Get version.
2061  *
2062  * @head: Pointer to "struct tomoyo_io_buffer".
2063  *
2064  * Returns version information.
2065  */
2066 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
2067 {
2068 	if (!head->r.eof) {
2069 		tomoyo_io_printf(head, "2.4.0");
2070 		head->r.eof = true;
2071 	}
2072 }
2073 
2074 /**
2075  * tomoyo_read_self_domain - Get the current process's domainname.
2076  *
2077  * @head: Pointer to "struct tomoyo_io_buffer".
2078  *
2079  * Returns the current process's domainname.
2080  */
2081 static void tomoyo_read_self_domain(struct tomoyo_io_buffer *head)
2082 {
2083 	if (!head->r.eof) {
2084 		/*
2085 		 * tomoyo_domain()->domainname != NULL
2086 		 * because every process belongs to a domain and
2087 		 * the domain's name cannot be NULL.
2088 		 */
2089 		tomoyo_io_printf(head, "%s", tomoyo_domain()->domainname->name);
2090 		head->r.eof = true;
2091 	}
2092 }
2093 
2094 /* String table for /sys/kernel/security/tomoyo/stat interface. */
2095 static const char * const tomoyo_policy_headers[TOMOYO_MAX_POLICY_STAT] = {
2096 	[TOMOYO_STAT_POLICY_UPDATES]    = "update:",
2097 	[TOMOYO_STAT_POLICY_LEARNING]   = "violation in learning mode:",
2098 	[TOMOYO_STAT_POLICY_PERMISSIVE] = "violation in permissive mode:",
2099 	[TOMOYO_STAT_POLICY_ENFORCING]  = "violation in enforcing mode:",
2100 };
2101 
2102 /* String table for /sys/kernel/security/tomoyo/stat interface. */
2103 static const char * const tomoyo_memory_headers[TOMOYO_MAX_MEMORY_STAT] = {
2104 	[TOMOYO_MEMORY_POLICY] = "policy:",
2105 	[TOMOYO_MEMORY_AUDIT]  = "audit log:",
2106 	[TOMOYO_MEMORY_QUERY]  = "query message:",
2107 };
2108 
2109 /* Timestamp counter for last updated. */
2110 static unsigned int tomoyo_stat_updated[TOMOYO_MAX_POLICY_STAT];
2111 /* Counter for number of updates. */
2112 static unsigned int tomoyo_stat_modified[TOMOYO_MAX_POLICY_STAT];
2113 
2114 /**
2115  * tomoyo_update_stat - Update statistic counters.
2116  *
2117  * @index: Index for policy type.
2118  *
2119  * Returns nothing.
2120  */
2121 void tomoyo_update_stat(const u8 index)
2122 {
2123 	struct timeval tv;
2124 	do_gettimeofday(&tv);
2125 	/*
2126 	 * I don't use atomic operations because race condition is not fatal.
2127 	 */
2128 	tomoyo_stat_updated[index]++;
2129 	tomoyo_stat_modified[index] = tv.tv_sec;
2130 }
2131 
2132 /**
2133  * tomoyo_read_stat - Read statistic data.
2134  *
2135  * @head: Pointer to "struct tomoyo_io_buffer".
2136  *
2137  * Returns nothing.
2138  */
2139 static void tomoyo_read_stat(struct tomoyo_io_buffer *head)
2140 {
2141 	u8 i;
2142 	unsigned int total = 0;
2143 	if (head->r.eof)
2144 		return;
2145 	for (i = 0; i < TOMOYO_MAX_POLICY_STAT; i++) {
2146 		tomoyo_io_printf(head, "Policy %-30s %10u",
2147 				 tomoyo_policy_headers[i],
2148 				 tomoyo_stat_updated[i]);
2149 		if (tomoyo_stat_modified[i]) {
2150 			struct tomoyo_time stamp;
2151 			tomoyo_convert_time(tomoyo_stat_modified[i], &stamp);
2152 			tomoyo_io_printf(head, " (Last: %04u/%02u/%02u "
2153 					 "%02u:%02u:%02u)",
2154 					 stamp.year, stamp.month, stamp.day,
2155 					 stamp.hour, stamp.min, stamp.sec);
2156 		}
2157 		tomoyo_set_lf(head);
2158 	}
2159 	for (i = 0; i < TOMOYO_MAX_MEMORY_STAT; i++) {
2160 		unsigned int used = tomoyo_memory_used[i];
2161 		total += used;
2162 		tomoyo_io_printf(head, "Memory used by %-22s %10u",
2163 				 tomoyo_memory_headers[i], used);
2164 		used = tomoyo_memory_quota[i];
2165 		if (used)
2166 			tomoyo_io_printf(head, " (Quota: %10u)", used);
2167 		tomoyo_set_lf(head);
2168 	}
2169 	tomoyo_io_printf(head, "Total memory used:                    %10u\n",
2170 			 total);
2171 	head->r.eof = true;
2172 }
2173 
2174 /**
2175  * tomoyo_write_stat - Set memory quota.
2176  *
2177  * @head: Pointer to "struct tomoyo_io_buffer".
2178  *
2179  * Returns 0.
2180  */
2181 static int tomoyo_write_stat(struct tomoyo_io_buffer *head)
2182 {
2183 	char *data = head->write_buf;
2184 	u8 i;
2185 	if (tomoyo_str_starts(&data, "Memory used by "))
2186 		for (i = 0; i < TOMOYO_MAX_MEMORY_STAT; i++)
2187 			if (tomoyo_str_starts(&data, tomoyo_memory_headers[i]))
2188 				sscanf(data, "%u", &tomoyo_memory_quota[i]);
2189 	return 0;
2190 }
2191 
2192 /**
2193  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
2194  *
2195  * @type: Type of interface.
2196  * @file: Pointer to "struct file".
2197  *
2198  * Returns 0 on success, negative value otherwise.
2199  */
2200 int tomoyo_open_control(const u8 type, struct file *file)
2201 {
2202 	struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
2203 
2204 	if (!head)
2205 		return -ENOMEM;
2206 	mutex_init(&head->io_sem);
2207 	head->type = type;
2208 	switch (type) {
2209 	case TOMOYO_DOMAINPOLICY:
2210 		/* /sys/kernel/security/tomoyo/domain_policy */
2211 		head->write = tomoyo_write_domain;
2212 		head->read = tomoyo_read_domain;
2213 		break;
2214 	case TOMOYO_EXCEPTIONPOLICY:
2215 		/* /sys/kernel/security/tomoyo/exception_policy */
2216 		head->write = tomoyo_write_exception;
2217 		head->read = tomoyo_read_exception;
2218 		break;
2219 	case TOMOYO_AUDIT:
2220 		/* /sys/kernel/security/tomoyo/audit */
2221 		head->poll = tomoyo_poll_log;
2222 		head->read = tomoyo_read_log;
2223 		break;
2224 	case TOMOYO_SELFDOMAIN:
2225 		/* /sys/kernel/security/tomoyo/self_domain */
2226 		head->read = tomoyo_read_self_domain;
2227 		break;
2228 	case TOMOYO_PROCESS_STATUS:
2229 		/* /sys/kernel/security/tomoyo/.process_status */
2230 		head->write = tomoyo_write_pid;
2231 		head->read = tomoyo_read_pid;
2232 		break;
2233 	case TOMOYO_VERSION:
2234 		/* /sys/kernel/security/tomoyo/version */
2235 		head->read = tomoyo_read_version;
2236 		head->readbuf_size = 128;
2237 		break;
2238 	case TOMOYO_STAT:
2239 		/* /sys/kernel/security/tomoyo/stat */
2240 		head->write = tomoyo_write_stat;
2241 		head->read = tomoyo_read_stat;
2242 		head->readbuf_size = 1024;
2243 		break;
2244 	case TOMOYO_PROFILE:
2245 		/* /sys/kernel/security/tomoyo/profile */
2246 		head->write = tomoyo_write_profile;
2247 		head->read = tomoyo_read_profile;
2248 		break;
2249 	case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
2250 		head->poll = tomoyo_poll_query;
2251 		head->write = tomoyo_write_answer;
2252 		head->read = tomoyo_read_query;
2253 		break;
2254 	case TOMOYO_MANAGER:
2255 		/* /sys/kernel/security/tomoyo/manager */
2256 		head->write = tomoyo_write_manager;
2257 		head->read = tomoyo_read_manager;
2258 		break;
2259 	}
2260 	if (!(file->f_mode & FMODE_READ)) {
2261 		/*
2262 		 * No need to allocate read_buf since it is not opened
2263 		 * for reading.
2264 		 */
2265 		head->read = NULL;
2266 		head->poll = NULL;
2267 	} else if (!head->poll) {
2268 		/* Don't allocate read_buf for poll() access. */
2269 		if (!head->readbuf_size)
2270 			head->readbuf_size = 4096 * 2;
2271 		head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
2272 		if (!head->read_buf) {
2273 			kfree(head);
2274 			return -ENOMEM;
2275 		}
2276 	}
2277 	if (!(file->f_mode & FMODE_WRITE)) {
2278 		/*
2279 		 * No need to allocate write_buf since it is not opened
2280 		 * for writing.
2281 		 */
2282 		head->write = NULL;
2283 	} else if (head->write) {
2284 		head->writebuf_size = 4096 * 2;
2285 		head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
2286 		if (!head->write_buf) {
2287 			kfree(head->read_buf);
2288 			kfree(head);
2289 			return -ENOMEM;
2290 		}
2291 	}
2292 	/*
2293 	 * If the file is /sys/kernel/security/tomoyo/query , increment the
2294 	 * observer counter.
2295 	 * The obserber counter is used by tomoyo_supervisor() to see if
2296 	 * there is some process monitoring /sys/kernel/security/tomoyo/query.
2297 	 */
2298 	if (type == TOMOYO_QUERY)
2299 		atomic_inc(&tomoyo_query_observers);
2300 	file->private_data = head;
2301 	tomoyo_notify_gc(head, true);
2302 	return 0;
2303 }
2304 
2305 /**
2306  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
2307  *
2308  * @file: Pointer to "struct file".
2309  * @wait: Pointer to "poll_table".
2310  *
2311  * Waits for read readiness.
2312  * /sys/kernel/security/tomoyo/query is handled by /usr/sbin/tomoyo-queryd and
2313  * /sys/kernel/security/tomoyo/audit is handled by /usr/sbin/tomoyo-auditd.
2314  */
2315 int tomoyo_poll_control(struct file *file, poll_table *wait)
2316 {
2317 	struct tomoyo_io_buffer *head = file->private_data;
2318 	if (!head->poll)
2319 		return -ENOSYS;
2320 	return head->poll(file, wait);
2321 }
2322 
2323 /**
2324  * tomoyo_set_namespace_cursor - Set namespace to read.
2325  *
2326  * @head: Pointer to "struct tomoyo_io_buffer".
2327  *
2328  * Returns nothing.
2329  */
2330 static inline void tomoyo_set_namespace_cursor(struct tomoyo_io_buffer *head)
2331 {
2332 	struct list_head *ns;
2333 	if (head->type != TOMOYO_EXCEPTIONPOLICY &&
2334 	    head->type != TOMOYO_PROFILE)
2335 		return;
2336 	/*
2337 	 * If this is the first read, or reading previous namespace finished
2338 	 * and has more namespaces to read, update the namespace cursor.
2339 	 */
2340 	ns = head->r.ns;
2341 	if (!ns || (head->r.eof && ns->next != &tomoyo_namespace_list)) {
2342 		/* Clearing is OK because tomoyo_flush() returned true. */
2343 		memset(&head->r, 0, sizeof(head->r));
2344 		head->r.ns = ns ? ns->next : tomoyo_namespace_list.next;
2345 	}
2346 }
2347 
2348 /**
2349  * tomoyo_has_more_namespace - Check for unread namespaces.
2350  *
2351  * @head: Pointer to "struct tomoyo_io_buffer".
2352  *
2353  * Returns true if we have more entries to print, false otherwise.
2354  */
2355 static inline bool tomoyo_has_more_namespace(struct tomoyo_io_buffer *head)
2356 {
2357 	return (head->type == TOMOYO_EXCEPTIONPOLICY ||
2358 		head->type == TOMOYO_PROFILE) && head->r.eof &&
2359 		head->r.ns->next != &tomoyo_namespace_list;
2360 }
2361 
2362 /**
2363  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
2364  *
2365  * @head:       Pointer to "struct tomoyo_io_buffer".
2366  * @buffer:     Poiner to buffer to write to.
2367  * @buffer_len: Size of @buffer.
2368  *
2369  * Returns bytes read on success, negative value otherwise.
2370  */
2371 ssize_t tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
2372 			    const int buffer_len)
2373 {
2374 	int len;
2375 	int idx;
2376 
2377 	if (!head->read)
2378 		return -ENOSYS;
2379 	if (mutex_lock_interruptible(&head->io_sem))
2380 		return -EINTR;
2381 	head->read_user_buf = buffer;
2382 	head->read_user_buf_avail = buffer_len;
2383 	idx = tomoyo_read_lock();
2384 	if (tomoyo_flush(head))
2385 		/* Call the policy handler. */
2386 		do {
2387 			tomoyo_set_namespace_cursor(head);
2388 			head->read(head);
2389 		} while (tomoyo_flush(head) &&
2390 			 tomoyo_has_more_namespace(head));
2391 	tomoyo_read_unlock(idx);
2392 	len = head->read_user_buf - buffer;
2393 	mutex_unlock(&head->io_sem);
2394 	return len;
2395 }
2396 
2397 /**
2398  * tomoyo_parse_policy - Parse a policy line.
2399  *
2400  * @head: Poiter to "struct tomoyo_io_buffer".
2401  * @line: Line to parse.
2402  *
2403  * Returns 0 on success, negative value otherwise.
2404  *
2405  * Caller holds tomoyo_read_lock().
2406  */
2407 static int tomoyo_parse_policy(struct tomoyo_io_buffer *head, char *line)
2408 {
2409 	/* Delete request? */
2410 	head->w.is_delete = !strncmp(line, "delete ", 7);
2411 	if (head->w.is_delete)
2412 		memmove(line, line + 7, strlen(line + 7) + 1);
2413 	/* Selecting namespace to update. */
2414 	if (head->type == TOMOYO_EXCEPTIONPOLICY ||
2415 	    head->type == TOMOYO_PROFILE) {
2416 		if (*line == '<') {
2417 			char *cp = strchr(line, ' ');
2418 			if (cp) {
2419 				*cp++ = '\0';
2420 				head->w.ns = tomoyo_assign_namespace(line);
2421 				memmove(line, cp, strlen(cp) + 1);
2422 			} else
2423 				head->w.ns = NULL;
2424 		} else
2425 			head->w.ns = &tomoyo_kernel_namespace;
2426 		/* Don't allow updating if namespace is invalid. */
2427 		if (!head->w.ns)
2428 			return -ENOENT;
2429 	}
2430 	/* Do the update. */
2431 	return head->write(head);
2432 }
2433 
2434 /**
2435  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
2436  *
2437  * @head:       Pointer to "struct tomoyo_io_buffer".
2438  * @buffer:     Pointer to buffer to read from.
2439  * @buffer_len: Size of @buffer.
2440  *
2441  * Returns @buffer_len on success, negative value otherwise.
2442  */
2443 ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head,
2444 			     const char __user *buffer, const int buffer_len)
2445 {
2446 	int error = buffer_len;
2447 	size_t avail_len = buffer_len;
2448 	char *cp0 = head->write_buf;
2449 	int idx;
2450 	if (!head->write)
2451 		return -ENOSYS;
2452 	if (!access_ok(VERIFY_READ, buffer, buffer_len))
2453 		return -EFAULT;
2454 	if (mutex_lock_interruptible(&head->io_sem))
2455 		return -EINTR;
2456 	idx = tomoyo_read_lock();
2457 	/* Read a line and dispatch it to the policy handler. */
2458 	while (avail_len > 0) {
2459 		char c;
2460 		if (head->w.avail >= head->writebuf_size - 1) {
2461 			const int len = head->writebuf_size * 2;
2462 			char *cp = kzalloc(len, GFP_NOFS);
2463 			if (!cp) {
2464 				error = -ENOMEM;
2465 				break;
2466 			}
2467 			memmove(cp, cp0, head->w.avail);
2468 			kfree(cp0);
2469 			head->write_buf = cp;
2470 			cp0 = cp;
2471 			head->writebuf_size = len;
2472 		}
2473 		if (get_user(c, buffer)) {
2474 			error = -EFAULT;
2475 			break;
2476 		}
2477 		buffer++;
2478 		avail_len--;
2479 		cp0[head->w.avail++] = c;
2480 		if (c != '\n')
2481 			continue;
2482 		cp0[head->w.avail - 1] = '\0';
2483 		head->w.avail = 0;
2484 		tomoyo_normalize_line(cp0);
2485 		if (!strcmp(cp0, "reset")) {
2486 			head->w.ns = &tomoyo_kernel_namespace;
2487 			head->w.domain = NULL;
2488 			memset(&head->r, 0, sizeof(head->r));
2489 			continue;
2490 		}
2491 		/* Don't allow updating policies by non manager programs. */
2492 		switch (head->type) {
2493 		case TOMOYO_PROCESS_STATUS:
2494 			/* This does not write anything. */
2495 			break;
2496 		case TOMOYO_DOMAINPOLICY:
2497 			if (tomoyo_select_domain(head, cp0))
2498 				continue;
2499 			/* fall through */
2500 		case TOMOYO_EXCEPTIONPOLICY:
2501 			if (!strcmp(cp0, "select transition_only")) {
2502 				head->r.print_transition_related_only = true;
2503 				continue;
2504 			}
2505 			/* fall through */
2506 		default:
2507 			if (!tomoyo_manager()) {
2508 				error = -EPERM;
2509 				goto out;
2510 			}
2511 		}
2512 		switch (tomoyo_parse_policy(head, cp0)) {
2513 		case -EPERM:
2514 			error = -EPERM;
2515 			goto out;
2516 		case 0:
2517 			switch (head->type) {
2518 			case TOMOYO_DOMAINPOLICY:
2519 			case TOMOYO_EXCEPTIONPOLICY:
2520 			case TOMOYO_STAT:
2521 			case TOMOYO_PROFILE:
2522 			case TOMOYO_MANAGER:
2523 				tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
2524 				break;
2525 			default:
2526 				break;
2527 			}
2528 			break;
2529 		}
2530 	}
2531 out:
2532 	tomoyo_read_unlock(idx);
2533 	mutex_unlock(&head->io_sem);
2534 	return error;
2535 }
2536 
2537 /**
2538  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
2539  *
2540  * @head: Pointer to "struct tomoyo_io_buffer".
2541  *
2542  * Returns 0.
2543  */
2544 int tomoyo_close_control(struct tomoyo_io_buffer *head)
2545 {
2546 	/*
2547 	 * If the file is /sys/kernel/security/tomoyo/query , decrement the
2548 	 * observer counter.
2549 	 */
2550 	if (head->type == TOMOYO_QUERY &&
2551 	    atomic_dec_and_test(&tomoyo_query_observers))
2552 		wake_up_all(&tomoyo_answer_wait);
2553 	tomoyo_notify_gc(head, false);
2554 	return 0;
2555 }
2556 
2557 /**
2558  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
2559  */
2560 void tomoyo_check_profile(void)
2561 {
2562 	struct tomoyo_domain_info *domain;
2563 	const int idx = tomoyo_read_lock();
2564 	tomoyo_policy_loaded = true;
2565 	printk(KERN_INFO "TOMOYO: 2.4.0\n");
2566 	list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
2567 		const u8 profile = domain->profile;
2568 		const struct tomoyo_policy_namespace *ns = domain->ns;
2569 		if (ns->profile_version != 20100903)
2570 			printk(KERN_ERR
2571 			       "Profile version %u is not supported.\n",
2572 			       ns->profile_version);
2573 		else if (!ns->profile_ptr[profile])
2574 			printk(KERN_ERR
2575 			       "Profile %u (used by '%s') is not defined.\n",
2576 			       profile, domain->domainname->name);
2577 		else
2578 			continue;
2579 		printk(KERN_ERR
2580 		       "Userland tools for TOMOYO 2.4 must be installed and "
2581 		       "policy must be initialized.\n");
2582 		printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.4/ "
2583 		       "for more information.\n");
2584 		panic("STOP!");
2585 	}
2586 	tomoyo_read_unlock(idx);
2587 	printk(KERN_INFO "Mandatory Access Control activated.\n");
2588 }
2589 
2590 /**
2591  * tomoyo_load_builtin_policy - Load built-in policy.
2592  *
2593  * Returns nothing.
2594  */
2595 void __init tomoyo_load_builtin_policy(void)
2596 {
2597 	/*
2598 	 * This include file is manually created and contains built-in policy
2599 	 * named "tomoyo_builtin_profile", "tomoyo_builtin_exception_policy",
2600 	 * "tomoyo_builtin_domain_policy", "tomoyo_builtin_manager",
2601 	 * "tomoyo_builtin_stat" in the form of "static char [] __initdata".
2602 	 */
2603 #include "builtin-policy.h"
2604 	u8 i;
2605 	const int idx = tomoyo_read_lock();
2606 	for (i = 0; i < 5; i++) {
2607 		struct tomoyo_io_buffer head = { };
2608 		char *start = "";
2609 		switch (i) {
2610 		case 0:
2611 			start = tomoyo_builtin_profile;
2612 			head.type = TOMOYO_PROFILE;
2613 			head.write = tomoyo_write_profile;
2614 			break;
2615 		case 1:
2616 			start = tomoyo_builtin_exception_policy;
2617 			head.type = TOMOYO_EXCEPTIONPOLICY;
2618 			head.write = tomoyo_write_exception;
2619 			break;
2620 		case 2:
2621 			start = tomoyo_builtin_domain_policy;
2622 			head.type = TOMOYO_DOMAINPOLICY;
2623 			head.write = tomoyo_write_domain;
2624 			break;
2625 		case 3:
2626 			start = tomoyo_builtin_manager;
2627 			head.type = TOMOYO_MANAGER;
2628 			head.write = tomoyo_write_manager;
2629 			break;
2630 		case 4:
2631 			start = tomoyo_builtin_stat;
2632 			head.type = TOMOYO_STAT;
2633 			head.write = tomoyo_write_stat;
2634 			break;
2635 		}
2636 		while (1) {
2637 			char *end = strchr(start, '\n');
2638 			if (!end)
2639 				break;
2640 			*end = '\0';
2641 			tomoyo_normalize_line(start);
2642 			head.write_buf = start;
2643 			tomoyo_parse_policy(&head, start);
2644 			start = end + 1;
2645 		}
2646 	}
2647 	tomoyo_read_unlock(idx);
2648 #ifdef CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER
2649 	tomoyo_check_profile();
2650 #endif
2651 }
2652