xref: /openbmc/linux/security/tomoyo/common.c (revision 63705da3)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * security/tomoyo/common.c
4  *
5  * Copyright (C) 2005-2011  NTT DATA CORPORATION
6  */
7 
8 #include <linux/uaccess.h>
9 #include <linux/slab.h>
10 #include <linux/security.h>
11 #include "common.h"
12 
13 /* String table for operation mode. */
14 const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE] = {
15 	[TOMOYO_CONFIG_DISABLED]   = "disabled",
16 	[TOMOYO_CONFIG_LEARNING]   = "learning",
17 	[TOMOYO_CONFIG_PERMISSIVE] = "permissive",
18 	[TOMOYO_CONFIG_ENFORCING]  = "enforcing"
19 };
20 
21 /* String table for /sys/kernel/security/tomoyo/profile */
22 const char * const tomoyo_mac_keywords[TOMOYO_MAX_MAC_INDEX
23 				       + TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
24 	/* CONFIG::file group */
25 	[TOMOYO_MAC_FILE_EXECUTE]    = "execute",
26 	[TOMOYO_MAC_FILE_OPEN]       = "open",
27 	[TOMOYO_MAC_FILE_CREATE]     = "create",
28 	[TOMOYO_MAC_FILE_UNLINK]     = "unlink",
29 	[TOMOYO_MAC_FILE_GETATTR]    = "getattr",
30 	[TOMOYO_MAC_FILE_MKDIR]      = "mkdir",
31 	[TOMOYO_MAC_FILE_RMDIR]      = "rmdir",
32 	[TOMOYO_MAC_FILE_MKFIFO]     = "mkfifo",
33 	[TOMOYO_MAC_FILE_MKSOCK]     = "mksock",
34 	[TOMOYO_MAC_FILE_TRUNCATE]   = "truncate",
35 	[TOMOYO_MAC_FILE_SYMLINK]    = "symlink",
36 	[TOMOYO_MAC_FILE_MKBLOCK]    = "mkblock",
37 	[TOMOYO_MAC_FILE_MKCHAR]     = "mkchar",
38 	[TOMOYO_MAC_FILE_LINK]       = "link",
39 	[TOMOYO_MAC_FILE_RENAME]     = "rename",
40 	[TOMOYO_MAC_FILE_CHMOD]      = "chmod",
41 	[TOMOYO_MAC_FILE_CHOWN]      = "chown",
42 	[TOMOYO_MAC_FILE_CHGRP]      = "chgrp",
43 	[TOMOYO_MAC_FILE_IOCTL]      = "ioctl",
44 	[TOMOYO_MAC_FILE_CHROOT]     = "chroot",
45 	[TOMOYO_MAC_FILE_MOUNT]      = "mount",
46 	[TOMOYO_MAC_FILE_UMOUNT]     = "unmount",
47 	[TOMOYO_MAC_FILE_PIVOT_ROOT] = "pivot_root",
48 	/* CONFIG::network group */
49 	[TOMOYO_MAC_NETWORK_INET_STREAM_BIND]       = "inet_stream_bind",
50 	[TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN]     = "inet_stream_listen",
51 	[TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT]    = "inet_stream_connect",
52 	[TOMOYO_MAC_NETWORK_INET_DGRAM_BIND]        = "inet_dgram_bind",
53 	[TOMOYO_MAC_NETWORK_INET_DGRAM_SEND]        = "inet_dgram_send",
54 	[TOMOYO_MAC_NETWORK_INET_RAW_BIND]          = "inet_raw_bind",
55 	[TOMOYO_MAC_NETWORK_INET_RAW_SEND]          = "inet_raw_send",
56 	[TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND]       = "unix_stream_bind",
57 	[TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN]     = "unix_stream_listen",
58 	[TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT]    = "unix_stream_connect",
59 	[TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND]        = "unix_dgram_bind",
60 	[TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND]        = "unix_dgram_send",
61 	[TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND]    = "unix_seqpacket_bind",
62 	[TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN]  = "unix_seqpacket_listen",
63 	[TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT] = "unix_seqpacket_connect",
64 	/* CONFIG::misc group */
65 	[TOMOYO_MAC_ENVIRON] = "env",
66 	/* CONFIG group */
67 	[TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_FILE] = "file",
68 	[TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_NETWORK] = "network",
69 	[TOMOYO_MAX_MAC_INDEX + TOMOYO_MAC_CATEGORY_MISC] = "misc",
70 };
71 
72 /* String table for conditions. */
73 const char * const tomoyo_condition_keyword[TOMOYO_MAX_CONDITION_KEYWORD] = {
74 	[TOMOYO_TASK_UID]             = "task.uid",
75 	[TOMOYO_TASK_EUID]            = "task.euid",
76 	[TOMOYO_TASK_SUID]            = "task.suid",
77 	[TOMOYO_TASK_FSUID]           = "task.fsuid",
78 	[TOMOYO_TASK_GID]             = "task.gid",
79 	[TOMOYO_TASK_EGID]            = "task.egid",
80 	[TOMOYO_TASK_SGID]            = "task.sgid",
81 	[TOMOYO_TASK_FSGID]           = "task.fsgid",
82 	[TOMOYO_TASK_PID]             = "task.pid",
83 	[TOMOYO_TASK_PPID]            = "task.ppid",
84 	[TOMOYO_EXEC_ARGC]            = "exec.argc",
85 	[TOMOYO_EXEC_ENVC]            = "exec.envc",
86 	[TOMOYO_TYPE_IS_SOCKET]       = "socket",
87 	[TOMOYO_TYPE_IS_SYMLINK]      = "symlink",
88 	[TOMOYO_TYPE_IS_FILE]         = "file",
89 	[TOMOYO_TYPE_IS_BLOCK_DEV]    = "block",
90 	[TOMOYO_TYPE_IS_DIRECTORY]    = "directory",
91 	[TOMOYO_TYPE_IS_CHAR_DEV]     = "char",
92 	[TOMOYO_TYPE_IS_FIFO]         = "fifo",
93 	[TOMOYO_MODE_SETUID]          = "setuid",
94 	[TOMOYO_MODE_SETGID]          = "setgid",
95 	[TOMOYO_MODE_STICKY]          = "sticky",
96 	[TOMOYO_MODE_OWNER_READ]      = "owner_read",
97 	[TOMOYO_MODE_OWNER_WRITE]     = "owner_write",
98 	[TOMOYO_MODE_OWNER_EXECUTE]   = "owner_execute",
99 	[TOMOYO_MODE_GROUP_READ]      = "group_read",
100 	[TOMOYO_MODE_GROUP_WRITE]     = "group_write",
101 	[TOMOYO_MODE_GROUP_EXECUTE]   = "group_execute",
102 	[TOMOYO_MODE_OTHERS_READ]     = "others_read",
103 	[TOMOYO_MODE_OTHERS_WRITE]    = "others_write",
104 	[TOMOYO_MODE_OTHERS_EXECUTE]  = "others_execute",
105 	[TOMOYO_EXEC_REALPATH]        = "exec.realpath",
106 	[TOMOYO_SYMLINK_TARGET]       = "symlink.target",
107 	[TOMOYO_PATH1_UID]            = "path1.uid",
108 	[TOMOYO_PATH1_GID]            = "path1.gid",
109 	[TOMOYO_PATH1_INO]            = "path1.ino",
110 	[TOMOYO_PATH1_MAJOR]          = "path1.major",
111 	[TOMOYO_PATH1_MINOR]          = "path1.minor",
112 	[TOMOYO_PATH1_PERM]           = "path1.perm",
113 	[TOMOYO_PATH1_TYPE]           = "path1.type",
114 	[TOMOYO_PATH1_DEV_MAJOR]      = "path1.dev_major",
115 	[TOMOYO_PATH1_DEV_MINOR]      = "path1.dev_minor",
116 	[TOMOYO_PATH2_UID]            = "path2.uid",
117 	[TOMOYO_PATH2_GID]            = "path2.gid",
118 	[TOMOYO_PATH2_INO]            = "path2.ino",
119 	[TOMOYO_PATH2_MAJOR]          = "path2.major",
120 	[TOMOYO_PATH2_MINOR]          = "path2.minor",
121 	[TOMOYO_PATH2_PERM]           = "path2.perm",
122 	[TOMOYO_PATH2_TYPE]           = "path2.type",
123 	[TOMOYO_PATH2_DEV_MAJOR]      = "path2.dev_major",
124 	[TOMOYO_PATH2_DEV_MINOR]      = "path2.dev_minor",
125 	[TOMOYO_PATH1_PARENT_UID]     = "path1.parent.uid",
126 	[TOMOYO_PATH1_PARENT_GID]     = "path1.parent.gid",
127 	[TOMOYO_PATH1_PARENT_INO]     = "path1.parent.ino",
128 	[TOMOYO_PATH1_PARENT_PERM]    = "path1.parent.perm",
129 	[TOMOYO_PATH2_PARENT_UID]     = "path2.parent.uid",
130 	[TOMOYO_PATH2_PARENT_GID]     = "path2.parent.gid",
131 	[TOMOYO_PATH2_PARENT_INO]     = "path2.parent.ino",
132 	[TOMOYO_PATH2_PARENT_PERM]    = "path2.parent.perm",
133 };
134 
135 /* String table for PREFERENCE keyword. */
136 static const char * const tomoyo_pref_keywords[TOMOYO_MAX_PREF] = {
137 	[TOMOYO_PREF_MAX_AUDIT_LOG]      = "max_audit_log",
138 	[TOMOYO_PREF_MAX_LEARNING_ENTRY] = "max_learning_entry",
139 };
140 
141 /* String table for path operation. */
142 const char * const tomoyo_path_keyword[TOMOYO_MAX_PATH_OPERATION] = {
143 	[TOMOYO_TYPE_EXECUTE]    = "execute",
144 	[TOMOYO_TYPE_READ]       = "read",
145 	[TOMOYO_TYPE_WRITE]      = "write",
146 	[TOMOYO_TYPE_APPEND]     = "append",
147 	[TOMOYO_TYPE_UNLINK]     = "unlink",
148 	[TOMOYO_TYPE_GETATTR]    = "getattr",
149 	[TOMOYO_TYPE_RMDIR]      = "rmdir",
150 	[TOMOYO_TYPE_TRUNCATE]   = "truncate",
151 	[TOMOYO_TYPE_SYMLINK]    = "symlink",
152 	[TOMOYO_TYPE_CHROOT]     = "chroot",
153 	[TOMOYO_TYPE_UMOUNT]     = "unmount",
154 };
155 
156 /* String table for socket's operation. */
157 const char * const tomoyo_socket_keyword[TOMOYO_MAX_NETWORK_OPERATION] = {
158 	[TOMOYO_NETWORK_BIND]    = "bind",
159 	[TOMOYO_NETWORK_LISTEN]  = "listen",
160 	[TOMOYO_NETWORK_CONNECT] = "connect",
161 	[TOMOYO_NETWORK_SEND]    = "send",
162 };
163 
164 /* String table for categories. */
165 static const char * const tomoyo_category_keywords
166 [TOMOYO_MAX_MAC_CATEGORY_INDEX] = {
167 	[TOMOYO_MAC_CATEGORY_FILE]    = "file",
168 	[TOMOYO_MAC_CATEGORY_NETWORK] = "network",
169 	[TOMOYO_MAC_CATEGORY_MISC]    = "misc",
170 };
171 
172 /* Permit policy management by non-root user? */
173 static bool tomoyo_manage_by_non_root;
174 
175 /* Utility functions. */
176 
177 /**
178  * tomoyo_yesno - Return "yes" or "no".
179  *
180  * @value: Bool value.
181  */
182 const char *tomoyo_yesno(const unsigned int value)
183 {
184 	return value ? "yes" : "no";
185 }
186 
187 /**
188  * tomoyo_addprintf - strncat()-like-snprintf().
189  *
190  * @buffer: Buffer to write to. Must be '\0'-terminated.
191  * @len:    Size of @buffer.
192  * @fmt:    The printf()'s format string, followed by parameters.
193  *
194  * Returns nothing.
195  */
196 static void tomoyo_addprintf(char *buffer, int len, const char *fmt, ...)
197 {
198 	va_list args;
199 	const int pos = strlen(buffer);
200 
201 	va_start(args, fmt);
202 	vsnprintf(buffer + pos, len - pos - 1, fmt, args);
203 	va_end(args);
204 }
205 
206 /**
207  * tomoyo_flush - Flush queued string to userspace's buffer.
208  *
209  * @head:   Pointer to "struct tomoyo_io_buffer".
210  *
211  * Returns true if all data was flushed, false otherwise.
212  */
213 static bool tomoyo_flush(struct tomoyo_io_buffer *head)
214 {
215 	while (head->r.w_pos) {
216 		const char *w = head->r.w[0];
217 		size_t len = strlen(w);
218 
219 		if (len) {
220 			if (len > head->read_user_buf_avail)
221 				len = head->read_user_buf_avail;
222 			if (!len)
223 				return false;
224 			if (copy_to_user(head->read_user_buf, w, len))
225 				return false;
226 			head->read_user_buf_avail -= len;
227 			head->read_user_buf += len;
228 			w += len;
229 		}
230 		head->r.w[0] = w;
231 		if (*w)
232 			return false;
233 		/* Add '\0' for audit logs and query. */
234 		if (head->poll) {
235 			if (!head->read_user_buf_avail ||
236 			    copy_to_user(head->read_user_buf, "", 1))
237 				return false;
238 			head->read_user_buf_avail--;
239 			head->read_user_buf++;
240 		}
241 		head->r.w_pos--;
242 		for (len = 0; len < head->r.w_pos; len++)
243 			head->r.w[len] = head->r.w[len + 1];
244 	}
245 	head->r.avail = 0;
246 	return true;
247 }
248 
249 /**
250  * tomoyo_set_string - Queue string to "struct tomoyo_io_buffer" structure.
251  *
252  * @head:   Pointer to "struct tomoyo_io_buffer".
253  * @string: String to print.
254  *
255  * Note that @string has to be kept valid until @head is kfree()d.
256  * This means that char[] allocated on stack memory cannot be passed to
257  * this function. Use tomoyo_io_printf() for char[] allocated on stack memory.
258  */
259 static void tomoyo_set_string(struct tomoyo_io_buffer *head, const char *string)
260 {
261 	if (head->r.w_pos < TOMOYO_MAX_IO_READ_QUEUE) {
262 		head->r.w[head->r.w_pos++] = string;
263 		tomoyo_flush(head);
264 	} else
265 		WARN_ON(1);
266 }
267 
268 static void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt,
269 			     ...) __printf(2, 3);
270 
271 /**
272  * tomoyo_io_printf - printf() to "struct tomoyo_io_buffer" structure.
273  *
274  * @head: Pointer to "struct tomoyo_io_buffer".
275  * @fmt:  The printf()'s format string, followed by parameters.
276  */
277 static void tomoyo_io_printf(struct tomoyo_io_buffer *head, const char *fmt,
278 			     ...)
279 {
280 	va_list args;
281 	size_t len;
282 	size_t pos = head->r.avail;
283 	int size = head->readbuf_size - pos;
284 
285 	if (size <= 0)
286 		return;
287 	va_start(args, fmt);
288 	len = vsnprintf(head->read_buf + pos, size, fmt, args) + 1;
289 	va_end(args);
290 	if (pos + len >= head->readbuf_size) {
291 		WARN_ON(1);
292 		return;
293 	}
294 	head->r.avail += len;
295 	tomoyo_set_string(head, head->read_buf + pos);
296 }
297 
298 /**
299  * tomoyo_set_space - Put a space to "struct tomoyo_io_buffer" structure.
300  *
301  * @head: Pointer to "struct tomoyo_io_buffer".
302  *
303  * Returns nothing.
304  */
305 static void tomoyo_set_space(struct tomoyo_io_buffer *head)
306 {
307 	tomoyo_set_string(head, " ");
308 }
309 
310 /**
311  * tomoyo_set_lf - Put a line feed to "struct tomoyo_io_buffer" structure.
312  *
313  * @head: Pointer to "struct tomoyo_io_buffer".
314  *
315  * Returns nothing.
316  */
317 static bool tomoyo_set_lf(struct tomoyo_io_buffer *head)
318 {
319 	tomoyo_set_string(head, "\n");
320 	return !head->r.w_pos;
321 }
322 
323 /**
324  * tomoyo_set_slash - Put a shash to "struct tomoyo_io_buffer" structure.
325  *
326  * @head: Pointer to "struct tomoyo_io_buffer".
327  *
328  * Returns nothing.
329  */
330 static void tomoyo_set_slash(struct tomoyo_io_buffer *head)
331 {
332 	tomoyo_set_string(head, "/");
333 }
334 
335 /* List of namespaces. */
336 LIST_HEAD(tomoyo_namespace_list);
337 /* True if namespace other than tomoyo_kernel_namespace is defined. */
338 static bool tomoyo_namespace_enabled;
339 
340 /**
341  * tomoyo_init_policy_namespace - Initialize namespace.
342  *
343  * @ns: Pointer to "struct tomoyo_policy_namespace".
344  *
345  * Returns nothing.
346  */
347 void tomoyo_init_policy_namespace(struct tomoyo_policy_namespace *ns)
348 {
349 	unsigned int idx;
350 
351 	for (idx = 0; idx < TOMOYO_MAX_ACL_GROUPS; idx++)
352 		INIT_LIST_HEAD(&ns->acl_group[idx]);
353 	for (idx = 0; idx < TOMOYO_MAX_GROUP; idx++)
354 		INIT_LIST_HEAD(&ns->group_list[idx]);
355 	for (idx = 0; idx < TOMOYO_MAX_POLICY; idx++)
356 		INIT_LIST_HEAD(&ns->policy_list[idx]);
357 	ns->profile_version = 20150505;
358 	tomoyo_namespace_enabled = !list_empty(&tomoyo_namespace_list);
359 	list_add_tail_rcu(&ns->namespace_list, &tomoyo_namespace_list);
360 }
361 
362 /**
363  * tomoyo_print_namespace - Print namespace header.
364  *
365  * @head: Pointer to "struct tomoyo_io_buffer".
366  *
367  * Returns nothing.
368  */
369 static void tomoyo_print_namespace(struct tomoyo_io_buffer *head)
370 {
371 	if (!tomoyo_namespace_enabled)
372 		return;
373 	tomoyo_set_string(head,
374 			  container_of(head->r.ns,
375 				       struct tomoyo_policy_namespace,
376 				       namespace_list)->name);
377 	tomoyo_set_space(head);
378 }
379 
380 /**
381  * tomoyo_print_name_union - Print a tomoyo_name_union.
382  *
383  * @head: Pointer to "struct tomoyo_io_buffer".
384  * @ptr:  Pointer to "struct tomoyo_name_union".
385  */
386 static void tomoyo_print_name_union(struct tomoyo_io_buffer *head,
387 				    const struct tomoyo_name_union *ptr)
388 {
389 	tomoyo_set_space(head);
390 	if (ptr->group) {
391 		tomoyo_set_string(head, "@");
392 		tomoyo_set_string(head, ptr->group->group_name->name);
393 	} else {
394 		tomoyo_set_string(head, ptr->filename->name);
395 	}
396 }
397 
398 /**
399  * tomoyo_print_name_union_quoted - Print a tomoyo_name_union with a quote.
400  *
401  * @head: Pointer to "struct tomoyo_io_buffer".
402  * @ptr:  Pointer to "struct tomoyo_name_union".
403  *
404  * Returns nothing.
405  */
406 static void tomoyo_print_name_union_quoted(struct tomoyo_io_buffer *head,
407 					   const struct tomoyo_name_union *ptr)
408 {
409 	if (ptr->group) {
410 		tomoyo_set_string(head, "@");
411 		tomoyo_set_string(head, ptr->group->group_name->name);
412 	} else {
413 		tomoyo_set_string(head, "\"");
414 		tomoyo_set_string(head, ptr->filename->name);
415 		tomoyo_set_string(head, "\"");
416 	}
417 }
418 
419 /**
420  * tomoyo_print_number_union_nospace - Print a tomoyo_number_union without a space.
421  *
422  * @head: Pointer to "struct tomoyo_io_buffer".
423  * @ptr:  Pointer to "struct tomoyo_number_union".
424  *
425  * Returns nothing.
426  */
427 static void tomoyo_print_number_union_nospace
428 (struct tomoyo_io_buffer *head, const struct tomoyo_number_union *ptr)
429 {
430 	if (ptr->group) {
431 		tomoyo_set_string(head, "@");
432 		tomoyo_set_string(head, ptr->group->group_name->name);
433 	} else {
434 		int i;
435 		unsigned long min = ptr->values[0];
436 		const unsigned long max = ptr->values[1];
437 		u8 min_type = ptr->value_type[0];
438 		const u8 max_type = ptr->value_type[1];
439 		char buffer[128];
440 
441 		buffer[0] = '\0';
442 		for (i = 0; i < 2; i++) {
443 			switch (min_type) {
444 			case TOMOYO_VALUE_TYPE_HEXADECIMAL:
445 				tomoyo_addprintf(buffer, sizeof(buffer),
446 						 "0x%lX", min);
447 				break;
448 			case TOMOYO_VALUE_TYPE_OCTAL:
449 				tomoyo_addprintf(buffer, sizeof(buffer),
450 						 "0%lo", min);
451 				break;
452 			default:
453 				tomoyo_addprintf(buffer, sizeof(buffer), "%lu",
454 						 min);
455 				break;
456 			}
457 			if (min == max && min_type == max_type)
458 				break;
459 			tomoyo_addprintf(buffer, sizeof(buffer), "-");
460 			min_type = max_type;
461 			min = max;
462 		}
463 		tomoyo_io_printf(head, "%s", buffer);
464 	}
465 }
466 
467 /**
468  * tomoyo_print_number_union - Print a tomoyo_number_union.
469  *
470  * @head: Pointer to "struct tomoyo_io_buffer".
471  * @ptr:  Pointer to "struct tomoyo_number_union".
472  *
473  * Returns nothing.
474  */
475 static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
476 				      const struct tomoyo_number_union *ptr)
477 {
478 	tomoyo_set_space(head);
479 	tomoyo_print_number_union_nospace(head, ptr);
480 }
481 
482 /**
483  * tomoyo_assign_profile - Create a new profile.
484  *
485  * @ns:      Pointer to "struct tomoyo_policy_namespace".
486  * @profile: Profile number to create.
487  *
488  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
489  */
490 static struct tomoyo_profile *tomoyo_assign_profile
491 (struct tomoyo_policy_namespace *ns, const unsigned int profile)
492 {
493 	struct tomoyo_profile *ptr;
494 	struct tomoyo_profile *entry;
495 
496 	if (profile >= TOMOYO_MAX_PROFILES)
497 		return NULL;
498 	ptr = ns->profile_ptr[profile];
499 	if (ptr)
500 		return ptr;
501 	entry = kzalloc(sizeof(*entry), GFP_NOFS | __GFP_NOWARN);
502 	if (mutex_lock_interruptible(&tomoyo_policy_lock))
503 		goto out;
504 	ptr = ns->profile_ptr[profile];
505 	if (!ptr && tomoyo_memory_ok(entry)) {
506 		ptr = entry;
507 		ptr->default_config = TOMOYO_CONFIG_DISABLED |
508 			TOMOYO_CONFIG_WANT_GRANT_LOG |
509 			TOMOYO_CONFIG_WANT_REJECT_LOG;
510 		memset(ptr->config, TOMOYO_CONFIG_USE_DEFAULT,
511 		       sizeof(ptr->config));
512 		ptr->pref[TOMOYO_PREF_MAX_AUDIT_LOG] =
513 			CONFIG_SECURITY_TOMOYO_MAX_AUDIT_LOG;
514 		ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] =
515 			CONFIG_SECURITY_TOMOYO_MAX_ACCEPT_ENTRY;
516 		mb(); /* Avoid out-of-order execution. */
517 		ns->profile_ptr[profile] = ptr;
518 		entry = NULL;
519 	}
520 	mutex_unlock(&tomoyo_policy_lock);
521  out:
522 	kfree(entry);
523 	return ptr;
524 }
525 
526 /**
527  * tomoyo_profile - Find a profile.
528  *
529  * @ns:      Pointer to "struct tomoyo_policy_namespace".
530  * @profile: Profile number to find.
531  *
532  * Returns pointer to "struct tomoyo_profile".
533  */
534 struct tomoyo_profile *tomoyo_profile(const struct tomoyo_policy_namespace *ns,
535 				      const u8 profile)
536 {
537 	static struct tomoyo_profile tomoyo_null_profile;
538 	struct tomoyo_profile *ptr = ns->profile_ptr[profile];
539 
540 	if (!ptr)
541 		ptr = &tomoyo_null_profile;
542 	return ptr;
543 }
544 
545 /**
546  * tomoyo_find_yesno - Find values for specified keyword.
547  *
548  * @string: String to check.
549  * @find:   Name of keyword.
550  *
551  * Returns 1 if "@find=yes" was found, 0 if "@find=no" was found, -1 otherwise.
552  */
553 static s8 tomoyo_find_yesno(const char *string, const char *find)
554 {
555 	const char *cp = strstr(string, find);
556 
557 	if (cp) {
558 		cp += strlen(find);
559 		if (!strncmp(cp, "=yes", 4))
560 			return 1;
561 		else if (!strncmp(cp, "=no", 3))
562 			return 0;
563 	}
564 	return -1;
565 }
566 
567 /**
568  * tomoyo_set_uint - Set value for specified preference.
569  *
570  * @i:      Pointer to "unsigned int".
571  * @string: String to check.
572  * @find:   Name of keyword.
573  *
574  * Returns nothing.
575  */
576 static void tomoyo_set_uint(unsigned int *i, const char *string,
577 			    const char *find)
578 {
579 	const char *cp = strstr(string, find);
580 
581 	if (cp)
582 		sscanf(cp + strlen(find), "=%u", i);
583 }
584 
585 /**
586  * tomoyo_set_mode - Set mode for specified profile.
587  *
588  * @name:    Name of functionality.
589  * @value:   Mode for @name.
590  * @profile: Pointer to "struct tomoyo_profile".
591  *
592  * Returns 0 on success, negative value otherwise.
593  */
594 static int tomoyo_set_mode(char *name, const char *value,
595 			   struct tomoyo_profile *profile)
596 {
597 	u8 i;
598 	u8 config;
599 
600 	if (!strcmp(name, "CONFIG")) {
601 		i = TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX;
602 		config = profile->default_config;
603 	} else if (tomoyo_str_starts(&name, "CONFIG::")) {
604 		config = 0;
605 		for (i = 0; i < TOMOYO_MAX_MAC_INDEX
606 			     + TOMOYO_MAX_MAC_CATEGORY_INDEX; i++) {
607 			int len = 0;
608 
609 			if (i < TOMOYO_MAX_MAC_INDEX) {
610 				const u8 c = tomoyo_index2category[i];
611 				const char *category =
612 					tomoyo_category_keywords[c];
613 
614 				len = strlen(category);
615 				if (strncmp(name, category, len) ||
616 				    name[len++] != ':' || name[len++] != ':')
617 					continue;
618 			}
619 			if (strcmp(name + len, tomoyo_mac_keywords[i]))
620 				continue;
621 			config = profile->config[i];
622 			break;
623 		}
624 		if (i == TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
625 			return -EINVAL;
626 	} else {
627 		return -EINVAL;
628 	}
629 	if (strstr(value, "use_default")) {
630 		config = TOMOYO_CONFIG_USE_DEFAULT;
631 	} else {
632 		u8 mode;
633 
634 		for (mode = 0; mode < 4; mode++)
635 			if (strstr(value, tomoyo_mode[mode]))
636 				/*
637 				 * Update lower 3 bits in order to distinguish
638 				 * 'config' from 'TOMOYO_CONFIG_USE_DEFAULT'.
639 				 */
640 				config = (config & ~7) | mode;
641 		if (config != TOMOYO_CONFIG_USE_DEFAULT) {
642 			switch (tomoyo_find_yesno(value, "grant_log")) {
643 			case 1:
644 				config |= TOMOYO_CONFIG_WANT_GRANT_LOG;
645 				break;
646 			case 0:
647 				config &= ~TOMOYO_CONFIG_WANT_GRANT_LOG;
648 				break;
649 			}
650 			switch (tomoyo_find_yesno(value, "reject_log")) {
651 			case 1:
652 				config |= TOMOYO_CONFIG_WANT_REJECT_LOG;
653 				break;
654 			case 0:
655 				config &= ~TOMOYO_CONFIG_WANT_REJECT_LOG;
656 				break;
657 			}
658 		}
659 	}
660 	if (i < TOMOYO_MAX_MAC_INDEX + TOMOYO_MAX_MAC_CATEGORY_INDEX)
661 		profile->config[i] = config;
662 	else if (config != TOMOYO_CONFIG_USE_DEFAULT)
663 		profile->default_config = config;
664 	return 0;
665 }
666 
667 /**
668  * tomoyo_write_profile - Write profile table.
669  *
670  * @head: Pointer to "struct tomoyo_io_buffer".
671  *
672  * Returns 0 on success, negative value otherwise.
673  */
674 static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
675 {
676 	char *data = head->write_buf;
677 	unsigned int i;
678 	char *cp;
679 	struct tomoyo_profile *profile;
680 
681 	if (sscanf(data, "PROFILE_VERSION=%u", &head->w.ns->profile_version)
682 	    == 1)
683 		return 0;
684 	i = simple_strtoul(data, &cp, 10);
685 	if (*cp != '-')
686 		return -EINVAL;
687 	data = cp + 1;
688 	profile = tomoyo_assign_profile(head->w.ns, i);
689 	if (!profile)
690 		return -EINVAL;
691 	cp = strchr(data, '=');
692 	if (!cp)
693 		return -EINVAL;
694 	*cp++ = '\0';
695 	if (!strcmp(data, "COMMENT")) {
696 		static DEFINE_SPINLOCK(lock);
697 		const struct tomoyo_path_info *new_comment
698 			= tomoyo_get_name(cp);
699 		const struct tomoyo_path_info *old_comment;
700 
701 		if (!new_comment)
702 			return -ENOMEM;
703 		spin_lock(&lock);
704 		old_comment = profile->comment;
705 		profile->comment = new_comment;
706 		spin_unlock(&lock);
707 		tomoyo_put_name(old_comment);
708 		return 0;
709 	}
710 	if (!strcmp(data, "PREFERENCE")) {
711 		for (i = 0; i < TOMOYO_MAX_PREF; i++)
712 			tomoyo_set_uint(&profile->pref[i], cp,
713 					tomoyo_pref_keywords[i]);
714 		return 0;
715 	}
716 	return tomoyo_set_mode(data, cp, profile);
717 }
718 
719 /**
720  * tomoyo_print_config - Print mode for specified functionality.
721  *
722  * @head:   Pointer to "struct tomoyo_io_buffer".
723  * @config: Mode for that functionality.
724  *
725  * Returns nothing.
726  *
727  * Caller prints functionality's name.
728  */
729 static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
730 {
731 	tomoyo_io_printf(head, "={ mode=%s grant_log=%s reject_log=%s }\n",
732 			 tomoyo_mode[config & 3],
733 			 tomoyo_yesno(config & TOMOYO_CONFIG_WANT_GRANT_LOG),
734 			 tomoyo_yesno(config & TOMOYO_CONFIG_WANT_REJECT_LOG));
735 }
736 
737 /**
738  * tomoyo_read_profile - Read profile table.
739  *
740  * @head: Pointer to "struct tomoyo_io_buffer".
741  *
742  * Returns nothing.
743  */
744 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
745 {
746 	u8 index;
747 	struct tomoyo_policy_namespace *ns =
748 		container_of(head->r.ns, typeof(*ns), namespace_list);
749 	const struct tomoyo_profile *profile;
750 
751 	if (head->r.eof)
752 		return;
753  next:
754 	index = head->r.index;
755 	profile = ns->profile_ptr[index];
756 	switch (head->r.step) {
757 	case 0:
758 		tomoyo_print_namespace(head);
759 		tomoyo_io_printf(head, "PROFILE_VERSION=%u\n",
760 				 ns->profile_version);
761 		head->r.step++;
762 		break;
763 	case 1:
764 		for ( ; head->r.index < TOMOYO_MAX_PROFILES;
765 		      head->r.index++)
766 			if (ns->profile_ptr[head->r.index])
767 				break;
768 		if (head->r.index == TOMOYO_MAX_PROFILES) {
769 			head->r.eof = true;
770 			return;
771 		}
772 		head->r.step++;
773 		break;
774 	case 2:
775 		{
776 			u8 i;
777 			const struct tomoyo_path_info *comment =
778 				profile->comment;
779 
780 			tomoyo_print_namespace(head);
781 			tomoyo_io_printf(head, "%u-COMMENT=", index);
782 			tomoyo_set_string(head, comment ? comment->name : "");
783 			tomoyo_set_lf(head);
784 			tomoyo_print_namespace(head);
785 			tomoyo_io_printf(head, "%u-PREFERENCE={ ", index);
786 			for (i = 0; i < TOMOYO_MAX_PREF; i++)
787 				tomoyo_io_printf(head, "%s=%u ",
788 						 tomoyo_pref_keywords[i],
789 						 profile->pref[i]);
790 			tomoyo_set_string(head, "}\n");
791 			head->r.step++;
792 		}
793 		break;
794 	case 3:
795 		{
796 			tomoyo_print_namespace(head);
797 			tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
798 			tomoyo_print_config(head, profile->default_config);
799 			head->r.bit = 0;
800 			head->r.step++;
801 		}
802 		break;
803 	case 4:
804 		for ( ; head->r.bit < TOMOYO_MAX_MAC_INDEX
805 			      + TOMOYO_MAX_MAC_CATEGORY_INDEX; head->r.bit++) {
806 			const u8 i = head->r.bit;
807 			const u8 config = profile->config[i];
808 
809 			if (config == TOMOYO_CONFIG_USE_DEFAULT)
810 				continue;
811 			tomoyo_print_namespace(head);
812 			if (i < TOMOYO_MAX_MAC_INDEX)
813 				tomoyo_io_printf(head, "%u-CONFIG::%s::%s",
814 						 index,
815 						 tomoyo_category_keywords
816 						 [tomoyo_index2category[i]],
817 						 tomoyo_mac_keywords[i]);
818 			else
819 				tomoyo_io_printf(head, "%u-CONFIG::%s", index,
820 						 tomoyo_mac_keywords[i]);
821 			tomoyo_print_config(head, config);
822 			head->r.bit++;
823 			break;
824 		}
825 		if (head->r.bit == TOMOYO_MAX_MAC_INDEX
826 		    + TOMOYO_MAX_MAC_CATEGORY_INDEX) {
827 			head->r.index++;
828 			head->r.step = 1;
829 		}
830 		break;
831 	}
832 	if (tomoyo_flush(head))
833 		goto next;
834 }
835 
836 /**
837  * tomoyo_same_manager - Check for duplicated "struct tomoyo_manager" entry.
838  *
839  * @a: Pointer to "struct tomoyo_acl_head".
840  * @b: Pointer to "struct tomoyo_acl_head".
841  *
842  * Returns true if @a == @b, false otherwise.
843  */
844 static bool tomoyo_same_manager(const struct tomoyo_acl_head *a,
845 				const struct tomoyo_acl_head *b)
846 {
847 	return container_of(a, struct tomoyo_manager, head)->manager ==
848 		container_of(b, struct tomoyo_manager, head)->manager;
849 }
850 
851 /**
852  * tomoyo_update_manager_entry - Add a manager entry.
853  *
854  * @manager:   The path to manager or the domainnamme.
855  * @is_delete: True if it is a delete request.
856  *
857  * Returns 0 on success, negative value otherwise.
858  *
859  * Caller holds tomoyo_read_lock().
860  */
861 static int tomoyo_update_manager_entry(const char *manager,
862 				       const bool is_delete)
863 {
864 	struct tomoyo_manager e = { };
865 	struct tomoyo_acl_param param = {
866 		/* .ns = &tomoyo_kernel_namespace, */
867 		.is_delete = is_delete,
868 		.list = &tomoyo_kernel_namespace.policy_list[TOMOYO_ID_MANAGER],
869 	};
870 	int error = is_delete ? -ENOENT : -ENOMEM;
871 
872 	if (!tomoyo_correct_domain(manager) &&
873 	    !tomoyo_correct_word(manager))
874 		return -EINVAL;
875 	e.manager = tomoyo_get_name(manager);
876 	if (e.manager) {
877 		error = tomoyo_update_policy(&e.head, sizeof(e), &param,
878 					     tomoyo_same_manager);
879 		tomoyo_put_name(e.manager);
880 	}
881 	return error;
882 }
883 
884 /**
885  * tomoyo_write_manager - Write manager policy.
886  *
887  * @head: Pointer to "struct tomoyo_io_buffer".
888  *
889  * Returns 0 on success, negative value otherwise.
890  *
891  * Caller holds tomoyo_read_lock().
892  */
893 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
894 {
895 	char *data = head->write_buf;
896 
897 	if (!strcmp(data, "manage_by_non_root")) {
898 		tomoyo_manage_by_non_root = !head->w.is_delete;
899 		return 0;
900 	}
901 	return tomoyo_update_manager_entry(data, head->w.is_delete);
902 }
903 
904 /**
905  * tomoyo_read_manager - Read manager policy.
906  *
907  * @head: Pointer to "struct tomoyo_io_buffer".
908  *
909  * Caller holds tomoyo_read_lock().
910  */
911 static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
912 {
913 	if (head->r.eof)
914 		return;
915 	list_for_each_cookie(head->r.acl, &tomoyo_kernel_namespace.policy_list[TOMOYO_ID_MANAGER]) {
916 		struct tomoyo_manager *ptr =
917 			list_entry(head->r.acl, typeof(*ptr), head.list);
918 
919 		if (ptr->head.is_deleted)
920 			continue;
921 		if (!tomoyo_flush(head))
922 			return;
923 		tomoyo_set_string(head, ptr->manager->name);
924 		tomoyo_set_lf(head);
925 	}
926 	head->r.eof = true;
927 }
928 
929 /**
930  * tomoyo_manager - Check whether the current process is a policy manager.
931  *
932  * Returns true if the current process is permitted to modify policy
933  * via /sys/kernel/security/tomoyo/ interface.
934  *
935  * Caller holds tomoyo_read_lock().
936  */
937 static bool tomoyo_manager(void)
938 {
939 	struct tomoyo_manager *ptr;
940 	const char *exe;
941 	const struct task_struct *task = current;
942 	const struct tomoyo_path_info *domainname = tomoyo_domain()->domainname;
943 	bool found = IS_ENABLED(CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING);
944 
945 	if (!tomoyo_policy_loaded)
946 		return true;
947 	if (!tomoyo_manage_by_non_root &&
948 	    (!uid_eq(task->cred->uid,  GLOBAL_ROOT_UID) ||
949 	     !uid_eq(task->cred->euid, GLOBAL_ROOT_UID)))
950 		return false;
951 	exe = tomoyo_get_exe();
952 	if (!exe)
953 		return false;
954 	list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.policy_list[TOMOYO_ID_MANAGER], head.list,
955 				srcu_read_lock_held(&tomoyo_ss)) {
956 		if (!ptr->head.is_deleted &&
957 		    (!tomoyo_pathcmp(domainname, ptr->manager) ||
958 		     !strcmp(exe, ptr->manager->name))) {
959 			found = true;
960 			break;
961 		}
962 	}
963 	if (!found) { /* Reduce error messages. */
964 		static pid_t last_pid;
965 		const pid_t pid = current->pid;
966 
967 		if (last_pid != pid) {
968 			pr_warn("%s ( %s ) is not permitted to update policies.\n",
969 				domainname->name, exe);
970 			last_pid = pid;
971 		}
972 	}
973 	kfree(exe);
974 	return found;
975 }
976 
977 static struct tomoyo_domain_info *tomoyo_find_domain_by_qid
978 (unsigned int serial);
979 
980 /**
981  * tomoyo_select_domain - Parse select command.
982  *
983  * @head: Pointer to "struct tomoyo_io_buffer".
984  * @data: String to parse.
985  *
986  * Returns true on success, false otherwise.
987  *
988  * Caller holds tomoyo_read_lock().
989  */
990 static bool tomoyo_select_domain(struct tomoyo_io_buffer *head,
991 				 const char *data)
992 {
993 	unsigned int pid;
994 	struct tomoyo_domain_info *domain = NULL;
995 	bool global_pid = false;
996 
997 	if (strncmp(data, "select ", 7))
998 		return false;
999 	data += 7;
1000 	if (sscanf(data, "pid=%u", &pid) == 1 ||
1001 	    (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
1002 		struct task_struct *p;
1003 
1004 		rcu_read_lock();
1005 		if (global_pid)
1006 			p = find_task_by_pid_ns(pid, &init_pid_ns);
1007 		else
1008 			p = find_task_by_vpid(pid);
1009 		if (p)
1010 			domain = tomoyo_task(p)->domain_info;
1011 		rcu_read_unlock();
1012 	} else if (!strncmp(data, "domain=", 7)) {
1013 		if (tomoyo_domain_def(data + 7))
1014 			domain = tomoyo_find_domain(data + 7);
1015 	} else if (sscanf(data, "Q=%u", &pid) == 1) {
1016 		domain = tomoyo_find_domain_by_qid(pid);
1017 	} else
1018 		return false;
1019 	head->w.domain = domain;
1020 	/* Accessing read_buf is safe because head->io_sem is held. */
1021 	if (!head->read_buf)
1022 		return true; /* Do nothing if open(O_WRONLY). */
1023 	memset(&head->r, 0, sizeof(head->r));
1024 	head->r.print_this_domain_only = true;
1025 	if (domain)
1026 		head->r.domain = &domain->list;
1027 	else
1028 		head->r.eof = true;
1029 	tomoyo_io_printf(head, "# select %s\n", data);
1030 	if (domain && domain->is_deleted)
1031 		tomoyo_io_printf(head, "# This is a deleted domain.\n");
1032 	return true;
1033 }
1034 
1035 /**
1036  * tomoyo_same_task_acl - Check for duplicated "struct tomoyo_task_acl" entry.
1037  *
1038  * @a: Pointer to "struct tomoyo_acl_info".
1039  * @b: Pointer to "struct tomoyo_acl_info".
1040  *
1041  * Returns true if @a == @b, false otherwise.
1042  */
1043 static bool tomoyo_same_task_acl(const struct tomoyo_acl_info *a,
1044 				 const struct tomoyo_acl_info *b)
1045 {
1046 	const struct tomoyo_task_acl *p1 = container_of(a, typeof(*p1), head);
1047 	const struct tomoyo_task_acl *p2 = container_of(b, typeof(*p2), head);
1048 
1049 	return p1->domainname == p2->domainname;
1050 }
1051 
1052 /**
1053  * tomoyo_write_task - Update task related list.
1054  *
1055  * @param: Pointer to "struct tomoyo_acl_param".
1056  *
1057  * Returns 0 on success, negative value otherwise.
1058  *
1059  * Caller holds tomoyo_read_lock().
1060  */
1061 static int tomoyo_write_task(struct tomoyo_acl_param *param)
1062 {
1063 	int error = -EINVAL;
1064 
1065 	if (tomoyo_str_starts(&param->data, "manual_domain_transition ")) {
1066 		struct tomoyo_task_acl e = {
1067 			.head.type = TOMOYO_TYPE_MANUAL_TASK_ACL,
1068 			.domainname = tomoyo_get_domainname(param),
1069 		};
1070 
1071 		if (e.domainname)
1072 			error = tomoyo_update_domain(&e.head, sizeof(e), param,
1073 						     tomoyo_same_task_acl,
1074 						     NULL);
1075 		tomoyo_put_name(e.domainname);
1076 	}
1077 	return error;
1078 }
1079 
1080 /**
1081  * tomoyo_delete_domain - Delete a domain.
1082  *
1083  * @domainname: The name of domain.
1084  *
1085  * Returns 0 on success, negative value otherwise.
1086  *
1087  * Caller holds tomoyo_read_lock().
1088  */
1089 static int tomoyo_delete_domain(char *domainname)
1090 {
1091 	struct tomoyo_domain_info *domain;
1092 	struct tomoyo_path_info name;
1093 
1094 	name.name = domainname;
1095 	tomoyo_fill_path_info(&name);
1096 	if (mutex_lock_interruptible(&tomoyo_policy_lock))
1097 		return -EINTR;
1098 	/* Is there an active domain? */
1099 	list_for_each_entry_rcu(domain, &tomoyo_domain_list, list,
1100 				srcu_read_lock_held(&tomoyo_ss)) {
1101 		/* Never delete tomoyo_kernel_domain */
1102 		if (domain == &tomoyo_kernel_domain)
1103 			continue;
1104 		if (domain->is_deleted ||
1105 		    tomoyo_pathcmp(domain->domainname, &name))
1106 			continue;
1107 		domain->is_deleted = true;
1108 		break;
1109 	}
1110 	mutex_unlock(&tomoyo_policy_lock);
1111 	return 0;
1112 }
1113 
1114 /**
1115  * tomoyo_write_domain2 - Write domain policy.
1116  *
1117  * @ns:        Pointer to "struct tomoyo_policy_namespace".
1118  * @list:      Pointer to "struct list_head".
1119  * @data:      Policy to be interpreted.
1120  * @is_delete: True if it is a delete request.
1121  *
1122  * Returns 0 on success, negative value otherwise.
1123  *
1124  * Caller holds tomoyo_read_lock().
1125  */
1126 static int tomoyo_write_domain2(struct tomoyo_policy_namespace *ns,
1127 				struct list_head *list, char *data,
1128 				const bool is_delete)
1129 {
1130 	struct tomoyo_acl_param param = {
1131 		.ns = ns,
1132 		.list = list,
1133 		.data = data,
1134 		.is_delete = is_delete,
1135 	};
1136 	static const struct {
1137 		const char *keyword;
1138 		int (*write)(struct tomoyo_acl_param *param);
1139 	} tomoyo_callback[5] = {
1140 		{ "file ", tomoyo_write_file },
1141 		{ "network inet ", tomoyo_write_inet_network },
1142 		{ "network unix ", tomoyo_write_unix_network },
1143 		{ "misc ", tomoyo_write_misc },
1144 		{ "task ", tomoyo_write_task },
1145 	};
1146 	u8 i;
1147 
1148 	for (i = 0; i < ARRAY_SIZE(tomoyo_callback); i++) {
1149 		if (!tomoyo_str_starts(&param.data,
1150 				       tomoyo_callback[i].keyword))
1151 			continue;
1152 		return tomoyo_callback[i].write(&param);
1153 	}
1154 	return -EINVAL;
1155 }
1156 
1157 /* String table for domain flags. */
1158 const char * const tomoyo_dif[TOMOYO_MAX_DOMAIN_INFO_FLAGS] = {
1159 	[TOMOYO_DIF_QUOTA_WARNED]      = "quota_exceeded\n",
1160 	[TOMOYO_DIF_TRANSITION_FAILED] = "transition_failed\n",
1161 };
1162 
1163 /**
1164  * tomoyo_write_domain - Write domain policy.
1165  *
1166  * @head: Pointer to "struct tomoyo_io_buffer".
1167  *
1168  * Returns 0 on success, negative value otherwise.
1169  *
1170  * Caller holds tomoyo_read_lock().
1171  */
1172 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
1173 {
1174 	char *data = head->write_buf;
1175 	struct tomoyo_policy_namespace *ns;
1176 	struct tomoyo_domain_info *domain = head->w.domain;
1177 	const bool is_delete = head->w.is_delete;
1178 	bool is_select = !is_delete && tomoyo_str_starts(&data, "select ");
1179 	unsigned int idx;
1180 
1181 	if (*data == '<') {
1182 		int ret = 0;
1183 
1184 		domain = NULL;
1185 		if (is_delete)
1186 			ret = tomoyo_delete_domain(data);
1187 		else if (is_select)
1188 			domain = tomoyo_find_domain(data);
1189 		else
1190 			domain = tomoyo_assign_domain(data, false);
1191 		head->w.domain = domain;
1192 		return ret;
1193 	}
1194 	if (!domain)
1195 		return -EINVAL;
1196 	ns = domain->ns;
1197 	if (sscanf(data, "use_profile %u", &idx) == 1
1198 	    && idx < TOMOYO_MAX_PROFILES) {
1199 		if (!tomoyo_policy_loaded || ns->profile_ptr[idx])
1200 			if (!is_delete)
1201 				domain->profile = (u8) idx;
1202 		return 0;
1203 	}
1204 	if (sscanf(data, "use_group %u\n", &idx) == 1
1205 	    && idx < TOMOYO_MAX_ACL_GROUPS) {
1206 		if (!is_delete)
1207 			set_bit(idx, domain->group);
1208 		else
1209 			clear_bit(idx, domain->group);
1210 		return 0;
1211 	}
1212 	for (idx = 0; idx < TOMOYO_MAX_DOMAIN_INFO_FLAGS; idx++) {
1213 		const char *cp = tomoyo_dif[idx];
1214 
1215 		if (strncmp(data, cp, strlen(cp) - 1))
1216 			continue;
1217 		domain->flags[idx] = !is_delete;
1218 		return 0;
1219 	}
1220 	return tomoyo_write_domain2(ns, &domain->acl_info_list, data,
1221 				    is_delete);
1222 }
1223 
1224 /**
1225  * tomoyo_print_condition - Print condition part.
1226  *
1227  * @head: Pointer to "struct tomoyo_io_buffer".
1228  * @cond: Pointer to "struct tomoyo_condition".
1229  *
1230  * Returns true on success, false otherwise.
1231  */
1232 static bool tomoyo_print_condition(struct tomoyo_io_buffer *head,
1233 				   const struct tomoyo_condition *cond)
1234 {
1235 	switch (head->r.cond_step) {
1236 	case 0:
1237 		head->r.cond_index = 0;
1238 		head->r.cond_step++;
1239 		if (cond->transit) {
1240 			tomoyo_set_space(head);
1241 			tomoyo_set_string(head, cond->transit->name);
1242 		}
1243 		fallthrough;
1244 	case 1:
1245 		{
1246 			const u16 condc = cond->condc;
1247 			const struct tomoyo_condition_element *condp =
1248 				(typeof(condp)) (cond + 1);
1249 			const struct tomoyo_number_union *numbers_p =
1250 				(typeof(numbers_p)) (condp + condc);
1251 			const struct tomoyo_name_union *names_p =
1252 				(typeof(names_p))
1253 				(numbers_p + cond->numbers_count);
1254 			const struct tomoyo_argv *argv =
1255 				(typeof(argv)) (names_p + cond->names_count);
1256 			const struct tomoyo_envp *envp =
1257 				(typeof(envp)) (argv + cond->argc);
1258 			u16 skip;
1259 
1260 			for (skip = 0; skip < head->r.cond_index; skip++) {
1261 				const u8 left = condp->left;
1262 				const u8 right = condp->right;
1263 
1264 				condp++;
1265 				switch (left) {
1266 				case TOMOYO_ARGV_ENTRY:
1267 					argv++;
1268 					continue;
1269 				case TOMOYO_ENVP_ENTRY:
1270 					envp++;
1271 					continue;
1272 				case TOMOYO_NUMBER_UNION:
1273 					numbers_p++;
1274 					break;
1275 				}
1276 				switch (right) {
1277 				case TOMOYO_NAME_UNION:
1278 					names_p++;
1279 					break;
1280 				case TOMOYO_NUMBER_UNION:
1281 					numbers_p++;
1282 					break;
1283 				}
1284 			}
1285 			while (head->r.cond_index < condc) {
1286 				const u8 match = condp->equals;
1287 				const u8 left = condp->left;
1288 				const u8 right = condp->right;
1289 
1290 				if (!tomoyo_flush(head))
1291 					return false;
1292 				condp++;
1293 				head->r.cond_index++;
1294 				tomoyo_set_space(head);
1295 				switch (left) {
1296 				case TOMOYO_ARGV_ENTRY:
1297 					tomoyo_io_printf(head,
1298 							 "exec.argv[%lu]%s=\"",
1299 							 argv->index, argv->is_not ? "!" : "");
1300 					tomoyo_set_string(head,
1301 							  argv->value->name);
1302 					tomoyo_set_string(head, "\"");
1303 					argv++;
1304 					continue;
1305 				case TOMOYO_ENVP_ENTRY:
1306 					tomoyo_set_string(head,
1307 							  "exec.envp[\"");
1308 					tomoyo_set_string(head,
1309 							  envp->name->name);
1310 					tomoyo_io_printf(head, "\"]%s=", envp->is_not ? "!" : "");
1311 					if (envp->value) {
1312 						tomoyo_set_string(head, "\"");
1313 						tomoyo_set_string(head, envp->value->name);
1314 						tomoyo_set_string(head, "\"");
1315 					} else {
1316 						tomoyo_set_string(head,
1317 								  "NULL");
1318 					}
1319 					envp++;
1320 					continue;
1321 				case TOMOYO_NUMBER_UNION:
1322 					tomoyo_print_number_union_nospace
1323 						(head, numbers_p++);
1324 					break;
1325 				default:
1326 					tomoyo_set_string(head,
1327 					       tomoyo_condition_keyword[left]);
1328 					break;
1329 				}
1330 				tomoyo_set_string(head, match ? "=" : "!=");
1331 				switch (right) {
1332 				case TOMOYO_NAME_UNION:
1333 					tomoyo_print_name_union_quoted
1334 						(head, names_p++);
1335 					break;
1336 				case TOMOYO_NUMBER_UNION:
1337 					tomoyo_print_number_union_nospace
1338 						(head, numbers_p++);
1339 					break;
1340 				default:
1341 					tomoyo_set_string(head,
1342 					  tomoyo_condition_keyword[right]);
1343 					break;
1344 				}
1345 			}
1346 		}
1347 		head->r.cond_step++;
1348 		fallthrough;
1349 	case 2:
1350 		if (!tomoyo_flush(head))
1351 			break;
1352 		head->r.cond_step++;
1353 		fallthrough;
1354 	case 3:
1355 		if (cond->grant_log != TOMOYO_GRANTLOG_AUTO)
1356 			tomoyo_io_printf(head, " grant_log=%s",
1357 					 tomoyo_yesno(cond->grant_log ==
1358 						      TOMOYO_GRANTLOG_YES));
1359 		tomoyo_set_lf(head);
1360 		return true;
1361 	}
1362 	return false;
1363 }
1364 
1365 /**
1366  * tomoyo_set_group - Print "acl_group " header keyword and category name.
1367  *
1368  * @head:     Pointer to "struct tomoyo_io_buffer".
1369  * @category: Category name.
1370  *
1371  * Returns nothing.
1372  */
1373 static void tomoyo_set_group(struct tomoyo_io_buffer *head,
1374 			     const char *category)
1375 {
1376 	if (head->type == TOMOYO_EXCEPTIONPOLICY) {
1377 		tomoyo_print_namespace(head);
1378 		tomoyo_io_printf(head, "acl_group %u ",
1379 				 head->r.acl_group_index);
1380 	}
1381 	tomoyo_set_string(head, category);
1382 }
1383 
1384 /**
1385  * tomoyo_print_entry - Print an ACL entry.
1386  *
1387  * @head: Pointer to "struct tomoyo_io_buffer".
1388  * @acl:  Pointer to an ACL entry.
1389  *
1390  * Returns true on success, false otherwise.
1391  */
1392 static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
1393 			       struct tomoyo_acl_info *acl)
1394 {
1395 	const u8 acl_type = acl->type;
1396 	bool first = true;
1397 	u8 bit;
1398 
1399 	if (head->r.print_cond_part)
1400 		goto print_cond_part;
1401 	if (acl->is_deleted)
1402 		return true;
1403 	if (!tomoyo_flush(head))
1404 		return false;
1405 	else if (acl_type == TOMOYO_TYPE_PATH_ACL) {
1406 		struct tomoyo_path_acl *ptr =
1407 			container_of(acl, typeof(*ptr), head);
1408 		const u16 perm = ptr->perm;
1409 
1410 		for (bit = 0; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
1411 			if (!(perm & (1 << bit)))
1412 				continue;
1413 			if (head->r.print_transition_related_only &&
1414 			    bit != TOMOYO_TYPE_EXECUTE)
1415 				continue;
1416 			if (first) {
1417 				tomoyo_set_group(head, "file ");
1418 				first = false;
1419 			} else {
1420 				tomoyo_set_slash(head);
1421 			}
1422 			tomoyo_set_string(head, tomoyo_path_keyword[bit]);
1423 		}
1424 		if (first)
1425 			return true;
1426 		tomoyo_print_name_union(head, &ptr->name);
1427 	} else if (acl_type == TOMOYO_TYPE_MANUAL_TASK_ACL) {
1428 		struct tomoyo_task_acl *ptr =
1429 			container_of(acl, typeof(*ptr), head);
1430 
1431 		tomoyo_set_group(head, "task ");
1432 		tomoyo_set_string(head, "manual_domain_transition ");
1433 		tomoyo_set_string(head, ptr->domainname->name);
1434 	} else if (head->r.print_transition_related_only) {
1435 		return true;
1436 	} else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
1437 		struct tomoyo_path2_acl *ptr =
1438 			container_of(acl, typeof(*ptr), head);
1439 		const u8 perm = ptr->perm;
1440 
1441 		for (bit = 0; bit < TOMOYO_MAX_PATH2_OPERATION; bit++) {
1442 			if (!(perm & (1 << bit)))
1443 				continue;
1444 			if (first) {
1445 				tomoyo_set_group(head, "file ");
1446 				first = false;
1447 			} else {
1448 				tomoyo_set_slash(head);
1449 			}
1450 			tomoyo_set_string(head, tomoyo_mac_keywords
1451 					  [tomoyo_pp2mac[bit]]);
1452 		}
1453 		if (first)
1454 			return true;
1455 		tomoyo_print_name_union(head, &ptr->name1);
1456 		tomoyo_print_name_union(head, &ptr->name2);
1457 	} else if (acl_type == TOMOYO_TYPE_PATH_NUMBER_ACL) {
1458 		struct tomoyo_path_number_acl *ptr =
1459 			container_of(acl, typeof(*ptr), head);
1460 		const u8 perm = ptr->perm;
1461 
1462 		for (bit = 0; bit < TOMOYO_MAX_PATH_NUMBER_OPERATION; bit++) {
1463 			if (!(perm & (1 << bit)))
1464 				continue;
1465 			if (first) {
1466 				tomoyo_set_group(head, "file ");
1467 				first = false;
1468 			} else {
1469 				tomoyo_set_slash(head);
1470 			}
1471 			tomoyo_set_string(head, tomoyo_mac_keywords
1472 					  [tomoyo_pn2mac[bit]]);
1473 		}
1474 		if (first)
1475 			return true;
1476 		tomoyo_print_name_union(head, &ptr->name);
1477 		tomoyo_print_number_union(head, &ptr->number);
1478 	} else if (acl_type == TOMOYO_TYPE_MKDEV_ACL) {
1479 		struct tomoyo_mkdev_acl *ptr =
1480 			container_of(acl, typeof(*ptr), head);
1481 		const u8 perm = ptr->perm;
1482 
1483 		for (bit = 0; bit < TOMOYO_MAX_MKDEV_OPERATION; bit++) {
1484 			if (!(perm & (1 << bit)))
1485 				continue;
1486 			if (first) {
1487 				tomoyo_set_group(head, "file ");
1488 				first = false;
1489 			} else {
1490 				tomoyo_set_slash(head);
1491 			}
1492 			tomoyo_set_string(head, tomoyo_mac_keywords
1493 					  [tomoyo_pnnn2mac[bit]]);
1494 		}
1495 		if (first)
1496 			return true;
1497 		tomoyo_print_name_union(head, &ptr->name);
1498 		tomoyo_print_number_union(head, &ptr->mode);
1499 		tomoyo_print_number_union(head, &ptr->major);
1500 		tomoyo_print_number_union(head, &ptr->minor);
1501 	} else if (acl_type == TOMOYO_TYPE_INET_ACL) {
1502 		struct tomoyo_inet_acl *ptr =
1503 			container_of(acl, typeof(*ptr), head);
1504 		const u8 perm = ptr->perm;
1505 
1506 		for (bit = 0; bit < TOMOYO_MAX_NETWORK_OPERATION; bit++) {
1507 			if (!(perm & (1 << bit)))
1508 				continue;
1509 			if (first) {
1510 				tomoyo_set_group(head, "network inet ");
1511 				tomoyo_set_string(head, tomoyo_proto_keyword
1512 						  [ptr->protocol]);
1513 				tomoyo_set_space(head);
1514 				first = false;
1515 			} else {
1516 				tomoyo_set_slash(head);
1517 			}
1518 			tomoyo_set_string(head, tomoyo_socket_keyword[bit]);
1519 		}
1520 		if (first)
1521 			return true;
1522 		tomoyo_set_space(head);
1523 		if (ptr->address.group) {
1524 			tomoyo_set_string(head, "@");
1525 			tomoyo_set_string(head, ptr->address.group->group_name
1526 					  ->name);
1527 		} else {
1528 			char buf[128];
1529 
1530 			tomoyo_print_ip(buf, sizeof(buf), &ptr->address);
1531 			tomoyo_io_printf(head, "%s", buf);
1532 		}
1533 		tomoyo_print_number_union(head, &ptr->port);
1534 	} else if (acl_type == TOMOYO_TYPE_UNIX_ACL) {
1535 		struct tomoyo_unix_acl *ptr =
1536 			container_of(acl, typeof(*ptr), head);
1537 		const u8 perm = ptr->perm;
1538 
1539 		for (bit = 0; bit < TOMOYO_MAX_NETWORK_OPERATION; bit++) {
1540 			if (!(perm & (1 << bit)))
1541 				continue;
1542 			if (first) {
1543 				tomoyo_set_group(head, "network unix ");
1544 				tomoyo_set_string(head, tomoyo_proto_keyword
1545 						  [ptr->protocol]);
1546 				tomoyo_set_space(head);
1547 				first = false;
1548 			} else {
1549 				tomoyo_set_slash(head);
1550 			}
1551 			tomoyo_set_string(head, tomoyo_socket_keyword[bit]);
1552 		}
1553 		if (first)
1554 			return true;
1555 		tomoyo_print_name_union(head, &ptr->name);
1556 	} else if (acl_type == TOMOYO_TYPE_MOUNT_ACL) {
1557 		struct tomoyo_mount_acl *ptr =
1558 			container_of(acl, typeof(*ptr), head);
1559 
1560 		tomoyo_set_group(head, "file mount");
1561 		tomoyo_print_name_union(head, &ptr->dev_name);
1562 		tomoyo_print_name_union(head, &ptr->dir_name);
1563 		tomoyo_print_name_union(head, &ptr->fs_type);
1564 		tomoyo_print_number_union(head, &ptr->flags);
1565 	} else if (acl_type == TOMOYO_TYPE_ENV_ACL) {
1566 		struct tomoyo_env_acl *ptr =
1567 			container_of(acl, typeof(*ptr), head);
1568 
1569 		tomoyo_set_group(head, "misc env ");
1570 		tomoyo_set_string(head, ptr->env->name);
1571 	}
1572 	if (acl->cond) {
1573 		head->r.print_cond_part = true;
1574 		head->r.cond_step = 0;
1575 		if (!tomoyo_flush(head))
1576 			return false;
1577 print_cond_part:
1578 		if (!tomoyo_print_condition(head, acl->cond))
1579 			return false;
1580 		head->r.print_cond_part = false;
1581 	} else {
1582 		tomoyo_set_lf(head);
1583 	}
1584 	return true;
1585 }
1586 
1587 /**
1588  * tomoyo_read_domain2 - Read domain policy.
1589  *
1590  * @head: Pointer to "struct tomoyo_io_buffer".
1591  * @list: Pointer to "struct list_head".
1592  *
1593  * Caller holds tomoyo_read_lock().
1594  *
1595  * Returns true on success, false otherwise.
1596  */
1597 static bool tomoyo_read_domain2(struct tomoyo_io_buffer *head,
1598 				struct list_head *list)
1599 {
1600 	list_for_each_cookie(head->r.acl, list) {
1601 		struct tomoyo_acl_info *ptr =
1602 			list_entry(head->r.acl, typeof(*ptr), list);
1603 
1604 		if (!tomoyo_print_entry(head, ptr))
1605 			return false;
1606 	}
1607 	head->r.acl = NULL;
1608 	return true;
1609 }
1610 
1611 /**
1612  * tomoyo_read_domain - Read domain policy.
1613  *
1614  * @head: Pointer to "struct tomoyo_io_buffer".
1615  *
1616  * Caller holds tomoyo_read_lock().
1617  */
1618 static void tomoyo_read_domain(struct tomoyo_io_buffer *head)
1619 {
1620 	if (head->r.eof)
1621 		return;
1622 	list_for_each_cookie(head->r.domain, &tomoyo_domain_list) {
1623 		struct tomoyo_domain_info *domain =
1624 			list_entry(head->r.domain, typeof(*domain), list);
1625 		u8 i;
1626 
1627 		switch (head->r.step) {
1628 		case 0:
1629 			if (domain->is_deleted &&
1630 			    !head->r.print_this_domain_only)
1631 				continue;
1632 			/* Print domainname and flags. */
1633 			tomoyo_set_string(head, domain->domainname->name);
1634 			tomoyo_set_lf(head);
1635 			tomoyo_io_printf(head, "use_profile %u\n",
1636 					 domain->profile);
1637 			for (i = 0; i < TOMOYO_MAX_DOMAIN_INFO_FLAGS; i++)
1638 				if (domain->flags[i])
1639 					tomoyo_set_string(head, tomoyo_dif[i]);
1640 			head->r.index = 0;
1641 			head->r.step++;
1642 			fallthrough;
1643 		case 1:
1644 			while (head->r.index < TOMOYO_MAX_ACL_GROUPS) {
1645 				i = head->r.index++;
1646 				if (!test_bit(i, domain->group))
1647 					continue;
1648 				tomoyo_io_printf(head, "use_group %u\n", i);
1649 				if (!tomoyo_flush(head))
1650 					return;
1651 			}
1652 			head->r.index = 0;
1653 			head->r.step++;
1654 			tomoyo_set_lf(head);
1655 			fallthrough;
1656 		case 2:
1657 			if (!tomoyo_read_domain2(head, &domain->acl_info_list))
1658 				return;
1659 			head->r.step++;
1660 			if (!tomoyo_set_lf(head))
1661 				return;
1662 			fallthrough;
1663 		case 3:
1664 			head->r.step = 0;
1665 			if (head->r.print_this_domain_only)
1666 				goto done;
1667 		}
1668 	}
1669  done:
1670 	head->r.eof = true;
1671 }
1672 
1673 /**
1674  * tomoyo_write_pid: Specify PID to obtain domainname.
1675  *
1676  * @head: Pointer to "struct tomoyo_io_buffer".
1677  *
1678  * Returns 0.
1679  */
1680 static int tomoyo_write_pid(struct tomoyo_io_buffer *head)
1681 {
1682 	head->r.eof = false;
1683 	return 0;
1684 }
1685 
1686 /**
1687  * tomoyo_read_pid - Get domainname of the specified PID.
1688  *
1689  * @head: Pointer to "struct tomoyo_io_buffer".
1690  *
1691  * Returns the domainname which the specified PID is in on success,
1692  * empty string otherwise.
1693  * The PID is specified by tomoyo_write_pid() so that the user can obtain
1694  * using read()/write() interface rather than sysctl() interface.
1695  */
1696 static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
1697 {
1698 	char *buf = head->write_buf;
1699 	bool global_pid = false;
1700 	unsigned int pid;
1701 	struct task_struct *p;
1702 	struct tomoyo_domain_info *domain = NULL;
1703 
1704 	/* Accessing write_buf is safe because head->io_sem is held. */
1705 	if (!buf) {
1706 		head->r.eof = true;
1707 		return; /* Do nothing if open(O_RDONLY). */
1708 	}
1709 	if (head->r.w_pos || head->r.eof)
1710 		return;
1711 	head->r.eof = true;
1712 	if (tomoyo_str_starts(&buf, "global-pid "))
1713 		global_pid = true;
1714 	if (kstrtouint(buf, 10, &pid))
1715 		return;
1716 	rcu_read_lock();
1717 	if (global_pid)
1718 		p = find_task_by_pid_ns(pid, &init_pid_ns);
1719 	else
1720 		p = find_task_by_vpid(pid);
1721 	if (p)
1722 		domain = tomoyo_task(p)->domain_info;
1723 	rcu_read_unlock();
1724 	if (!domain)
1725 		return;
1726 	tomoyo_io_printf(head, "%u %u ", pid, domain->profile);
1727 	tomoyo_set_string(head, domain->domainname->name);
1728 }
1729 
1730 /* String table for domain transition control keywords. */
1731 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
1732 	[TOMOYO_TRANSITION_CONTROL_NO_RESET]      = "no_reset_domain ",
1733 	[TOMOYO_TRANSITION_CONTROL_RESET]         = "reset_domain ",
1734 	[TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain ",
1735 	[TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain ",
1736 	[TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain ",
1737 	[TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain ",
1738 };
1739 
1740 /* String table for grouping keywords. */
1741 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
1742 	[TOMOYO_PATH_GROUP]    = "path_group ",
1743 	[TOMOYO_NUMBER_GROUP]  = "number_group ",
1744 	[TOMOYO_ADDRESS_GROUP] = "address_group ",
1745 };
1746 
1747 /**
1748  * tomoyo_write_exception - Write exception policy.
1749  *
1750  * @head: Pointer to "struct tomoyo_io_buffer".
1751  *
1752  * Returns 0 on success, negative value otherwise.
1753  *
1754  * Caller holds tomoyo_read_lock().
1755  */
1756 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
1757 {
1758 	const bool is_delete = head->w.is_delete;
1759 	struct tomoyo_acl_param param = {
1760 		.ns = head->w.ns,
1761 		.is_delete = is_delete,
1762 		.data = head->write_buf,
1763 	};
1764 	u8 i;
1765 
1766 	if (tomoyo_str_starts(&param.data, "aggregator "))
1767 		return tomoyo_write_aggregator(&param);
1768 	for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
1769 		if (tomoyo_str_starts(&param.data, tomoyo_transition_type[i]))
1770 			return tomoyo_write_transition_control(&param, i);
1771 	for (i = 0; i < TOMOYO_MAX_GROUP; i++)
1772 		if (tomoyo_str_starts(&param.data, tomoyo_group_name[i]))
1773 			return tomoyo_write_group(&param, i);
1774 	if (tomoyo_str_starts(&param.data, "acl_group ")) {
1775 		unsigned int group;
1776 		char *data;
1777 
1778 		group = simple_strtoul(param.data, &data, 10);
1779 		if (group < TOMOYO_MAX_ACL_GROUPS && *data++ == ' ')
1780 			return tomoyo_write_domain2
1781 				(head->w.ns, &head->w.ns->acl_group[group],
1782 				 data, is_delete);
1783 	}
1784 	return -EINVAL;
1785 }
1786 
1787 /**
1788  * tomoyo_read_group - Read "struct tomoyo_path_group"/"struct tomoyo_number_group"/"struct tomoyo_address_group" list.
1789  *
1790  * @head: Pointer to "struct tomoyo_io_buffer".
1791  * @idx:  Index number.
1792  *
1793  * Returns true on success, false otherwise.
1794  *
1795  * Caller holds tomoyo_read_lock().
1796  */
1797 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
1798 {
1799 	struct tomoyo_policy_namespace *ns =
1800 		container_of(head->r.ns, typeof(*ns), namespace_list);
1801 	struct list_head *list = &ns->group_list[idx];
1802 
1803 	list_for_each_cookie(head->r.group, list) {
1804 		struct tomoyo_group *group =
1805 			list_entry(head->r.group, typeof(*group), head.list);
1806 
1807 		list_for_each_cookie(head->r.acl, &group->member_list) {
1808 			struct tomoyo_acl_head *ptr =
1809 				list_entry(head->r.acl, typeof(*ptr), list);
1810 
1811 			if (ptr->is_deleted)
1812 				continue;
1813 			if (!tomoyo_flush(head))
1814 				return false;
1815 			tomoyo_print_namespace(head);
1816 			tomoyo_set_string(head, tomoyo_group_name[idx]);
1817 			tomoyo_set_string(head, group->group_name->name);
1818 			if (idx == TOMOYO_PATH_GROUP) {
1819 				tomoyo_set_space(head);
1820 				tomoyo_set_string(head, container_of
1821 					       (ptr, struct tomoyo_path_group,
1822 						head)->member_name->name);
1823 			} else if (idx == TOMOYO_NUMBER_GROUP) {
1824 				tomoyo_print_number_union(head, &container_of
1825 							  (ptr,
1826 						   struct tomoyo_number_group,
1827 							   head)->number);
1828 			} else if (idx == TOMOYO_ADDRESS_GROUP) {
1829 				char buffer[128];
1830 				struct tomoyo_address_group *member =
1831 					container_of(ptr, typeof(*member),
1832 						     head);
1833 
1834 				tomoyo_print_ip(buffer, sizeof(buffer),
1835 						&member->address);
1836 				tomoyo_io_printf(head, " %s", buffer);
1837 			}
1838 			tomoyo_set_lf(head);
1839 		}
1840 		head->r.acl = NULL;
1841 	}
1842 	head->r.group = NULL;
1843 	return true;
1844 }
1845 
1846 /**
1847  * tomoyo_read_policy - Read "struct tomoyo_..._entry" list.
1848  *
1849  * @head: Pointer to "struct tomoyo_io_buffer".
1850  * @idx:  Index number.
1851  *
1852  * Returns true on success, false otherwise.
1853  *
1854  * Caller holds tomoyo_read_lock().
1855  */
1856 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
1857 {
1858 	struct tomoyo_policy_namespace *ns =
1859 		container_of(head->r.ns, typeof(*ns), namespace_list);
1860 	struct list_head *list = &ns->policy_list[idx];
1861 
1862 	list_for_each_cookie(head->r.acl, list) {
1863 		struct tomoyo_acl_head *acl =
1864 			container_of(head->r.acl, typeof(*acl), list);
1865 		if (acl->is_deleted)
1866 			continue;
1867 		if (!tomoyo_flush(head))
1868 			return false;
1869 		switch (idx) {
1870 		case TOMOYO_ID_TRANSITION_CONTROL:
1871 			{
1872 				struct tomoyo_transition_control *ptr =
1873 					container_of(acl, typeof(*ptr), head);
1874 
1875 				tomoyo_print_namespace(head);
1876 				tomoyo_set_string(head, tomoyo_transition_type
1877 						  [ptr->type]);
1878 				tomoyo_set_string(head, ptr->program ?
1879 						  ptr->program->name : "any");
1880 				tomoyo_set_string(head, " from ");
1881 				tomoyo_set_string(head, ptr->domainname ?
1882 						  ptr->domainname->name :
1883 						  "any");
1884 			}
1885 			break;
1886 		case TOMOYO_ID_AGGREGATOR:
1887 			{
1888 				struct tomoyo_aggregator *ptr =
1889 					container_of(acl, typeof(*ptr), head);
1890 
1891 				tomoyo_print_namespace(head);
1892 				tomoyo_set_string(head, "aggregator ");
1893 				tomoyo_set_string(head,
1894 						  ptr->original_name->name);
1895 				tomoyo_set_space(head);
1896 				tomoyo_set_string(head,
1897 					       ptr->aggregated_name->name);
1898 			}
1899 			break;
1900 		default:
1901 			continue;
1902 		}
1903 		tomoyo_set_lf(head);
1904 	}
1905 	head->r.acl = NULL;
1906 	return true;
1907 }
1908 
1909 /**
1910  * tomoyo_read_exception - Read exception policy.
1911  *
1912  * @head: Pointer to "struct tomoyo_io_buffer".
1913  *
1914  * Caller holds tomoyo_read_lock().
1915  */
1916 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
1917 {
1918 	struct tomoyo_policy_namespace *ns =
1919 		container_of(head->r.ns, typeof(*ns), namespace_list);
1920 
1921 	if (head->r.eof)
1922 		return;
1923 	while (head->r.step < TOMOYO_MAX_POLICY &&
1924 	       tomoyo_read_policy(head, head->r.step))
1925 		head->r.step++;
1926 	if (head->r.step < TOMOYO_MAX_POLICY)
1927 		return;
1928 	while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP &&
1929 	       tomoyo_read_group(head, head->r.step - TOMOYO_MAX_POLICY))
1930 		head->r.step++;
1931 	if (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP)
1932 		return;
1933 	while (head->r.step < TOMOYO_MAX_POLICY + TOMOYO_MAX_GROUP
1934 	       + TOMOYO_MAX_ACL_GROUPS) {
1935 		head->r.acl_group_index = head->r.step - TOMOYO_MAX_POLICY
1936 			- TOMOYO_MAX_GROUP;
1937 		if (!tomoyo_read_domain2(head, &ns->acl_group
1938 					 [head->r.acl_group_index]))
1939 			return;
1940 		head->r.step++;
1941 	}
1942 	head->r.eof = true;
1943 }
1944 
1945 /* Wait queue for kernel -> userspace notification. */
1946 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_query_wait);
1947 /* Wait queue for userspace -> kernel notification. */
1948 static DECLARE_WAIT_QUEUE_HEAD(tomoyo_answer_wait);
1949 
1950 /* Structure for query. */
1951 struct tomoyo_query {
1952 	struct list_head list;
1953 	struct tomoyo_domain_info *domain;
1954 	char *query;
1955 	size_t query_len;
1956 	unsigned int serial;
1957 	u8 timer;
1958 	u8 answer;
1959 	u8 retry;
1960 };
1961 
1962 /* The list for "struct tomoyo_query". */
1963 static LIST_HEAD(tomoyo_query_list);
1964 
1965 /* Lock for manipulating tomoyo_query_list. */
1966 static DEFINE_SPINLOCK(tomoyo_query_list_lock);
1967 
1968 /*
1969  * Number of "struct file" referring /sys/kernel/security/tomoyo/query
1970  * interface.
1971  */
1972 static atomic_t tomoyo_query_observers = ATOMIC_INIT(0);
1973 
1974 /**
1975  * tomoyo_truncate - Truncate a line.
1976  *
1977  * @str: String to truncate.
1978  *
1979  * Returns length of truncated @str.
1980  */
1981 static int tomoyo_truncate(char *str)
1982 {
1983 	char *start = str;
1984 
1985 	while (*(unsigned char *) str > (unsigned char) ' ')
1986 		str++;
1987 	*str = '\0';
1988 	return strlen(start) + 1;
1989 }
1990 
1991 /**
1992  * tomoyo_add_entry - Add an ACL to current thread's domain. Used by learning mode.
1993  *
1994  * @domain: Pointer to "struct tomoyo_domain_info".
1995  * @header: Lines containing ACL.
1996  *
1997  * Returns nothing.
1998  */
1999 static void tomoyo_add_entry(struct tomoyo_domain_info *domain, char *header)
2000 {
2001 	char *buffer;
2002 	char *realpath = NULL;
2003 	char *argv0 = NULL;
2004 	char *symlink = NULL;
2005 	char *cp = strchr(header, '\n');
2006 	int len;
2007 
2008 	if (!cp)
2009 		return;
2010 	cp = strchr(cp + 1, '\n');
2011 	if (!cp)
2012 		return;
2013 	*cp++ = '\0';
2014 	len = strlen(cp) + 1;
2015 	/* strstr() will return NULL if ordering is wrong. */
2016 	if (*cp == 'f') {
2017 		argv0 = strstr(header, " argv[]={ \"");
2018 		if (argv0) {
2019 			argv0 += 10;
2020 			len += tomoyo_truncate(argv0) + 14;
2021 		}
2022 		realpath = strstr(header, " exec={ realpath=\"");
2023 		if (realpath) {
2024 			realpath += 8;
2025 			len += tomoyo_truncate(realpath) + 6;
2026 		}
2027 		symlink = strstr(header, " symlink.target=\"");
2028 		if (symlink)
2029 			len += tomoyo_truncate(symlink + 1) + 1;
2030 	}
2031 	buffer = kmalloc(len, GFP_NOFS);
2032 	if (!buffer)
2033 		return;
2034 	snprintf(buffer, len - 1, "%s", cp);
2035 	if (realpath)
2036 		tomoyo_addprintf(buffer, len, " exec.%s", realpath);
2037 	if (argv0)
2038 		tomoyo_addprintf(buffer, len, " exec.argv[0]=%s", argv0);
2039 	if (symlink)
2040 		tomoyo_addprintf(buffer, len, "%s", symlink);
2041 	tomoyo_normalize_line(buffer);
2042 	if (!tomoyo_write_domain2(domain->ns, &domain->acl_info_list, buffer,
2043 				  false))
2044 		tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
2045 	kfree(buffer);
2046 }
2047 
2048 /**
2049  * tomoyo_supervisor - Ask for the supervisor's decision.
2050  *
2051  * @r:   Pointer to "struct tomoyo_request_info".
2052  * @fmt: The printf()'s format string, followed by parameters.
2053  *
2054  * Returns 0 if the supervisor decided to permit the access request which
2055  * violated the policy in enforcing mode, TOMOYO_RETRY_REQUEST if the
2056  * supervisor decided to retry the access request which violated the policy in
2057  * enforcing mode, 0 if it is not in enforcing mode, -EPERM otherwise.
2058  */
2059 int tomoyo_supervisor(struct tomoyo_request_info *r, const char *fmt, ...)
2060 {
2061 	va_list args;
2062 	int error;
2063 	int len;
2064 	static unsigned int tomoyo_serial;
2065 	struct tomoyo_query entry = { };
2066 	bool quota_exceeded = false;
2067 
2068 	va_start(args, fmt);
2069 	len = vsnprintf((char *) &len, 1, fmt, args) + 1;
2070 	va_end(args);
2071 	/* Write /sys/kernel/security/tomoyo/audit. */
2072 	va_start(args, fmt);
2073 	tomoyo_write_log2(r, len, fmt, args);
2074 	va_end(args);
2075 	/* Nothing more to do if granted. */
2076 	if (r->granted)
2077 		return 0;
2078 	if (r->mode)
2079 		tomoyo_update_stat(r->mode);
2080 	switch (r->mode) {
2081 	case TOMOYO_CONFIG_ENFORCING:
2082 		error = -EPERM;
2083 		if (atomic_read(&tomoyo_query_observers))
2084 			break;
2085 		goto out;
2086 	case TOMOYO_CONFIG_LEARNING:
2087 		error = 0;
2088 		/* Check max_learning_entry parameter. */
2089 		if (tomoyo_domain_quota_is_ok(r))
2090 			break;
2091 		fallthrough;
2092 	default:
2093 		return 0;
2094 	}
2095 	/* Get message. */
2096 	va_start(args, fmt);
2097 	entry.query = tomoyo_init_log(r, len, fmt, args);
2098 	va_end(args);
2099 	if (!entry.query)
2100 		goto out;
2101 	entry.query_len = strlen(entry.query) + 1;
2102 	if (!error) {
2103 		tomoyo_add_entry(r->domain, entry.query);
2104 		goto out;
2105 	}
2106 	len = tomoyo_round2(entry.query_len);
2107 	entry.domain = r->domain;
2108 	spin_lock(&tomoyo_query_list_lock);
2109 	if (tomoyo_memory_quota[TOMOYO_MEMORY_QUERY] &&
2110 	    tomoyo_memory_used[TOMOYO_MEMORY_QUERY] + len
2111 	    >= tomoyo_memory_quota[TOMOYO_MEMORY_QUERY]) {
2112 		quota_exceeded = true;
2113 	} else {
2114 		entry.serial = tomoyo_serial++;
2115 		entry.retry = r->retry;
2116 		tomoyo_memory_used[TOMOYO_MEMORY_QUERY] += len;
2117 		list_add_tail(&entry.list, &tomoyo_query_list);
2118 	}
2119 	spin_unlock(&tomoyo_query_list_lock);
2120 	if (quota_exceeded)
2121 		goto out;
2122 	/* Give 10 seconds for supervisor's opinion. */
2123 	while (entry.timer < 10) {
2124 		wake_up_all(&tomoyo_query_wait);
2125 		if (wait_event_interruptible_timeout
2126 		    (tomoyo_answer_wait, entry.answer ||
2127 		     !atomic_read(&tomoyo_query_observers), HZ))
2128 			break;
2129 		entry.timer++;
2130 	}
2131 	spin_lock(&tomoyo_query_list_lock);
2132 	list_del(&entry.list);
2133 	tomoyo_memory_used[TOMOYO_MEMORY_QUERY] -= len;
2134 	spin_unlock(&tomoyo_query_list_lock);
2135 	switch (entry.answer) {
2136 	case 3: /* Asked to retry by administrator. */
2137 		error = TOMOYO_RETRY_REQUEST;
2138 		r->retry++;
2139 		break;
2140 	case 1:
2141 		/* Granted by administrator. */
2142 		error = 0;
2143 		break;
2144 	default:
2145 		/* Timed out or rejected by administrator. */
2146 		break;
2147 	}
2148 out:
2149 	kfree(entry.query);
2150 	return error;
2151 }
2152 
2153 /**
2154  * tomoyo_find_domain_by_qid - Get domain by query id.
2155  *
2156  * @serial: Query ID assigned by tomoyo_supervisor().
2157  *
2158  * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
2159  */
2160 static struct tomoyo_domain_info *tomoyo_find_domain_by_qid
2161 (unsigned int serial)
2162 {
2163 	struct tomoyo_query *ptr;
2164 	struct tomoyo_domain_info *domain = NULL;
2165 
2166 	spin_lock(&tomoyo_query_list_lock);
2167 	list_for_each_entry(ptr, &tomoyo_query_list, list) {
2168 		if (ptr->serial != serial)
2169 			continue;
2170 		domain = ptr->domain;
2171 		break;
2172 	}
2173 	spin_unlock(&tomoyo_query_list_lock);
2174 	return domain;
2175 }
2176 
2177 /**
2178  * tomoyo_poll_query - poll() for /sys/kernel/security/tomoyo/query.
2179  *
2180  * @file: Pointer to "struct file".
2181  * @wait: Pointer to "poll_table".
2182  *
2183  * Returns EPOLLIN | EPOLLRDNORM when ready to read, 0 otherwise.
2184  *
2185  * Waits for access requests which violated policy in enforcing mode.
2186  */
2187 static __poll_t tomoyo_poll_query(struct file *file, poll_table *wait)
2188 {
2189 	if (!list_empty(&tomoyo_query_list))
2190 		return EPOLLIN | EPOLLRDNORM;
2191 	poll_wait(file, &tomoyo_query_wait, wait);
2192 	if (!list_empty(&tomoyo_query_list))
2193 		return EPOLLIN | EPOLLRDNORM;
2194 	return 0;
2195 }
2196 
2197 /**
2198  * tomoyo_read_query - Read access requests which violated policy in enforcing mode.
2199  *
2200  * @head: Pointer to "struct tomoyo_io_buffer".
2201  */
2202 static void tomoyo_read_query(struct tomoyo_io_buffer *head)
2203 {
2204 	struct list_head *tmp;
2205 	unsigned int pos = 0;
2206 	size_t len = 0;
2207 	char *buf;
2208 
2209 	if (head->r.w_pos)
2210 		return;
2211 	kfree(head->read_buf);
2212 	head->read_buf = NULL;
2213 	spin_lock(&tomoyo_query_list_lock);
2214 	list_for_each(tmp, &tomoyo_query_list) {
2215 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2216 
2217 		if (pos++ != head->r.query_index)
2218 			continue;
2219 		len = ptr->query_len;
2220 		break;
2221 	}
2222 	spin_unlock(&tomoyo_query_list_lock);
2223 	if (!len) {
2224 		head->r.query_index = 0;
2225 		return;
2226 	}
2227 	buf = kzalloc(len + 32, GFP_NOFS);
2228 	if (!buf)
2229 		return;
2230 	pos = 0;
2231 	spin_lock(&tomoyo_query_list_lock);
2232 	list_for_each(tmp, &tomoyo_query_list) {
2233 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2234 
2235 		if (pos++ != head->r.query_index)
2236 			continue;
2237 		/*
2238 		 * Some query can be skipped because tomoyo_query_list
2239 		 * can change, but I don't care.
2240 		 */
2241 		if (len == ptr->query_len)
2242 			snprintf(buf, len + 31, "Q%u-%hu\n%s", ptr->serial,
2243 				 ptr->retry, ptr->query);
2244 		break;
2245 	}
2246 	spin_unlock(&tomoyo_query_list_lock);
2247 	if (buf[0]) {
2248 		head->read_buf = buf;
2249 		head->r.w[head->r.w_pos++] = buf;
2250 		head->r.query_index++;
2251 	} else {
2252 		kfree(buf);
2253 	}
2254 }
2255 
2256 /**
2257  * tomoyo_write_answer - Write the supervisor's decision.
2258  *
2259  * @head: Pointer to "struct tomoyo_io_buffer".
2260  *
2261  * Returns 0 on success, -EINVAL otherwise.
2262  */
2263 static int tomoyo_write_answer(struct tomoyo_io_buffer *head)
2264 {
2265 	char *data = head->write_buf;
2266 	struct list_head *tmp;
2267 	unsigned int serial;
2268 	unsigned int answer;
2269 
2270 	spin_lock(&tomoyo_query_list_lock);
2271 	list_for_each(tmp, &tomoyo_query_list) {
2272 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2273 
2274 		ptr->timer = 0;
2275 	}
2276 	spin_unlock(&tomoyo_query_list_lock);
2277 	if (sscanf(data, "A%u=%u", &serial, &answer) != 2)
2278 		return -EINVAL;
2279 	spin_lock(&tomoyo_query_list_lock);
2280 	list_for_each(tmp, &tomoyo_query_list) {
2281 		struct tomoyo_query *ptr = list_entry(tmp, typeof(*ptr), list);
2282 
2283 		if (ptr->serial != serial)
2284 			continue;
2285 		ptr->answer = answer;
2286 		/* Remove from tomoyo_query_list. */
2287 		if (ptr->answer)
2288 			list_del_init(&ptr->list);
2289 		break;
2290 	}
2291 	spin_unlock(&tomoyo_query_list_lock);
2292 	return 0;
2293 }
2294 
2295 /**
2296  * tomoyo_read_version: Get version.
2297  *
2298  * @head: Pointer to "struct tomoyo_io_buffer".
2299  *
2300  * Returns version information.
2301  */
2302 static void tomoyo_read_version(struct tomoyo_io_buffer *head)
2303 {
2304 	if (!head->r.eof) {
2305 		tomoyo_io_printf(head, "2.6.0");
2306 		head->r.eof = true;
2307 	}
2308 }
2309 
2310 /* String table for /sys/kernel/security/tomoyo/stat interface. */
2311 static const char * const tomoyo_policy_headers[TOMOYO_MAX_POLICY_STAT] = {
2312 	[TOMOYO_STAT_POLICY_UPDATES]    = "update:",
2313 	[TOMOYO_STAT_POLICY_LEARNING]   = "violation in learning mode:",
2314 	[TOMOYO_STAT_POLICY_PERMISSIVE] = "violation in permissive mode:",
2315 	[TOMOYO_STAT_POLICY_ENFORCING]  = "violation in enforcing mode:",
2316 };
2317 
2318 /* String table for /sys/kernel/security/tomoyo/stat interface. */
2319 static const char * const tomoyo_memory_headers[TOMOYO_MAX_MEMORY_STAT] = {
2320 	[TOMOYO_MEMORY_POLICY] = "policy:",
2321 	[TOMOYO_MEMORY_AUDIT]  = "audit log:",
2322 	[TOMOYO_MEMORY_QUERY]  = "query message:",
2323 };
2324 
2325 /* Counter for number of updates. */
2326 static atomic_t tomoyo_stat_updated[TOMOYO_MAX_POLICY_STAT];
2327 /* Timestamp counter for last updated. */
2328 static time64_t tomoyo_stat_modified[TOMOYO_MAX_POLICY_STAT];
2329 
2330 /**
2331  * tomoyo_update_stat - Update statistic counters.
2332  *
2333  * @index: Index for policy type.
2334  *
2335  * Returns nothing.
2336  */
2337 void tomoyo_update_stat(const u8 index)
2338 {
2339 	atomic_inc(&tomoyo_stat_updated[index]);
2340 	tomoyo_stat_modified[index] = ktime_get_real_seconds();
2341 }
2342 
2343 /**
2344  * tomoyo_read_stat - Read statistic data.
2345  *
2346  * @head: Pointer to "struct tomoyo_io_buffer".
2347  *
2348  * Returns nothing.
2349  */
2350 static void tomoyo_read_stat(struct tomoyo_io_buffer *head)
2351 {
2352 	u8 i;
2353 	unsigned int total = 0;
2354 
2355 	if (head->r.eof)
2356 		return;
2357 	for (i = 0; i < TOMOYO_MAX_POLICY_STAT; i++) {
2358 		tomoyo_io_printf(head, "Policy %-30s %10u",
2359 				 tomoyo_policy_headers[i],
2360 				 atomic_read(&tomoyo_stat_updated[i]));
2361 		if (tomoyo_stat_modified[i]) {
2362 			struct tomoyo_time stamp;
2363 
2364 			tomoyo_convert_time(tomoyo_stat_modified[i], &stamp);
2365 			tomoyo_io_printf(head, " (Last: %04u/%02u/%02u %02u:%02u:%02u)",
2366 					 stamp.year, stamp.month, stamp.day,
2367 					 stamp.hour, stamp.min, stamp.sec);
2368 		}
2369 		tomoyo_set_lf(head);
2370 	}
2371 	for (i = 0; i < TOMOYO_MAX_MEMORY_STAT; i++) {
2372 		unsigned int used = tomoyo_memory_used[i];
2373 
2374 		total += used;
2375 		tomoyo_io_printf(head, "Memory used by %-22s %10u",
2376 				 tomoyo_memory_headers[i], used);
2377 		used = tomoyo_memory_quota[i];
2378 		if (used)
2379 			tomoyo_io_printf(head, " (Quota: %10u)", used);
2380 		tomoyo_set_lf(head);
2381 	}
2382 	tomoyo_io_printf(head, "Total memory used:                    %10u\n",
2383 			 total);
2384 	head->r.eof = true;
2385 }
2386 
2387 /**
2388  * tomoyo_write_stat - Set memory quota.
2389  *
2390  * @head: Pointer to "struct tomoyo_io_buffer".
2391  *
2392  * Returns 0.
2393  */
2394 static int tomoyo_write_stat(struct tomoyo_io_buffer *head)
2395 {
2396 	char *data = head->write_buf;
2397 	u8 i;
2398 
2399 	if (tomoyo_str_starts(&data, "Memory used by "))
2400 		for (i = 0; i < TOMOYO_MAX_MEMORY_STAT; i++)
2401 			if (tomoyo_str_starts(&data, tomoyo_memory_headers[i]))
2402 				sscanf(data, "%u", &tomoyo_memory_quota[i]);
2403 	return 0;
2404 }
2405 
2406 /**
2407  * tomoyo_open_control - open() for /sys/kernel/security/tomoyo/ interface.
2408  *
2409  * @type: Type of interface.
2410  * @file: Pointer to "struct file".
2411  *
2412  * Returns 0 on success, negative value otherwise.
2413  */
2414 int tomoyo_open_control(const u8 type, struct file *file)
2415 {
2416 	struct tomoyo_io_buffer *head = kzalloc(sizeof(*head), GFP_NOFS);
2417 
2418 	if (!head)
2419 		return -ENOMEM;
2420 	mutex_init(&head->io_sem);
2421 	head->type = type;
2422 	switch (type) {
2423 	case TOMOYO_DOMAINPOLICY:
2424 		/* /sys/kernel/security/tomoyo/domain_policy */
2425 		head->write = tomoyo_write_domain;
2426 		head->read = tomoyo_read_domain;
2427 		break;
2428 	case TOMOYO_EXCEPTIONPOLICY:
2429 		/* /sys/kernel/security/tomoyo/exception_policy */
2430 		head->write = tomoyo_write_exception;
2431 		head->read = tomoyo_read_exception;
2432 		break;
2433 	case TOMOYO_AUDIT:
2434 		/* /sys/kernel/security/tomoyo/audit */
2435 		head->poll = tomoyo_poll_log;
2436 		head->read = tomoyo_read_log;
2437 		break;
2438 	case TOMOYO_PROCESS_STATUS:
2439 		/* /sys/kernel/security/tomoyo/.process_status */
2440 		head->write = tomoyo_write_pid;
2441 		head->read = tomoyo_read_pid;
2442 		break;
2443 	case TOMOYO_VERSION:
2444 		/* /sys/kernel/security/tomoyo/version */
2445 		head->read = tomoyo_read_version;
2446 		head->readbuf_size = 128;
2447 		break;
2448 	case TOMOYO_STAT:
2449 		/* /sys/kernel/security/tomoyo/stat */
2450 		head->write = tomoyo_write_stat;
2451 		head->read = tomoyo_read_stat;
2452 		head->readbuf_size = 1024;
2453 		break;
2454 	case TOMOYO_PROFILE:
2455 		/* /sys/kernel/security/tomoyo/profile */
2456 		head->write = tomoyo_write_profile;
2457 		head->read = tomoyo_read_profile;
2458 		break;
2459 	case TOMOYO_QUERY: /* /sys/kernel/security/tomoyo/query */
2460 		head->poll = tomoyo_poll_query;
2461 		head->write = tomoyo_write_answer;
2462 		head->read = tomoyo_read_query;
2463 		break;
2464 	case TOMOYO_MANAGER:
2465 		/* /sys/kernel/security/tomoyo/manager */
2466 		head->write = tomoyo_write_manager;
2467 		head->read = tomoyo_read_manager;
2468 		break;
2469 	}
2470 	if (!(file->f_mode & FMODE_READ)) {
2471 		/*
2472 		 * No need to allocate read_buf since it is not opened
2473 		 * for reading.
2474 		 */
2475 		head->read = NULL;
2476 		head->poll = NULL;
2477 	} else if (!head->poll) {
2478 		/* Don't allocate read_buf for poll() access. */
2479 		if (!head->readbuf_size)
2480 			head->readbuf_size = 4096 * 2;
2481 		head->read_buf = kzalloc(head->readbuf_size, GFP_NOFS);
2482 		if (!head->read_buf) {
2483 			kfree(head);
2484 			return -ENOMEM;
2485 		}
2486 	}
2487 	if (!(file->f_mode & FMODE_WRITE)) {
2488 		/*
2489 		 * No need to allocate write_buf since it is not opened
2490 		 * for writing.
2491 		 */
2492 		head->write = NULL;
2493 	} else if (head->write) {
2494 		head->writebuf_size = 4096 * 2;
2495 		head->write_buf = kzalloc(head->writebuf_size, GFP_NOFS);
2496 		if (!head->write_buf) {
2497 			kfree(head->read_buf);
2498 			kfree(head);
2499 			return -ENOMEM;
2500 		}
2501 	}
2502 	/*
2503 	 * If the file is /sys/kernel/security/tomoyo/query , increment the
2504 	 * observer counter.
2505 	 * The obserber counter is used by tomoyo_supervisor() to see if
2506 	 * there is some process monitoring /sys/kernel/security/tomoyo/query.
2507 	 */
2508 	if (type == TOMOYO_QUERY)
2509 		atomic_inc(&tomoyo_query_observers);
2510 	file->private_data = head;
2511 	tomoyo_notify_gc(head, true);
2512 	return 0;
2513 }
2514 
2515 /**
2516  * tomoyo_poll_control - poll() for /sys/kernel/security/tomoyo/ interface.
2517  *
2518  * @file: Pointer to "struct file".
2519  * @wait: Pointer to "poll_table". Maybe NULL.
2520  *
2521  * Returns EPOLLIN | EPOLLRDNORM | EPOLLOUT | EPOLLWRNORM if ready to read/write,
2522  * EPOLLOUT | EPOLLWRNORM otherwise.
2523  */
2524 __poll_t tomoyo_poll_control(struct file *file, poll_table *wait)
2525 {
2526 	struct tomoyo_io_buffer *head = file->private_data;
2527 
2528 	if (head->poll)
2529 		return head->poll(file, wait) | EPOLLOUT | EPOLLWRNORM;
2530 	return EPOLLIN | EPOLLRDNORM | EPOLLOUT | EPOLLWRNORM;
2531 }
2532 
2533 /**
2534  * tomoyo_set_namespace_cursor - Set namespace to read.
2535  *
2536  * @head: Pointer to "struct tomoyo_io_buffer".
2537  *
2538  * Returns nothing.
2539  */
2540 static inline void tomoyo_set_namespace_cursor(struct tomoyo_io_buffer *head)
2541 {
2542 	struct list_head *ns;
2543 
2544 	if (head->type != TOMOYO_EXCEPTIONPOLICY &&
2545 	    head->type != TOMOYO_PROFILE)
2546 		return;
2547 	/*
2548 	 * If this is the first read, or reading previous namespace finished
2549 	 * and has more namespaces to read, update the namespace cursor.
2550 	 */
2551 	ns = head->r.ns;
2552 	if (!ns || (head->r.eof && ns->next != &tomoyo_namespace_list)) {
2553 		/* Clearing is OK because tomoyo_flush() returned true. */
2554 		memset(&head->r, 0, sizeof(head->r));
2555 		head->r.ns = ns ? ns->next : tomoyo_namespace_list.next;
2556 	}
2557 }
2558 
2559 /**
2560  * tomoyo_has_more_namespace - Check for unread namespaces.
2561  *
2562  * @head: Pointer to "struct tomoyo_io_buffer".
2563  *
2564  * Returns true if we have more entries to print, false otherwise.
2565  */
2566 static inline bool tomoyo_has_more_namespace(struct tomoyo_io_buffer *head)
2567 {
2568 	return (head->type == TOMOYO_EXCEPTIONPOLICY ||
2569 		head->type == TOMOYO_PROFILE) && head->r.eof &&
2570 		head->r.ns->next != &tomoyo_namespace_list;
2571 }
2572 
2573 /**
2574  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
2575  *
2576  * @head:       Pointer to "struct tomoyo_io_buffer".
2577  * @buffer:     Pointer to buffer to write to.
2578  * @buffer_len: Size of @buffer.
2579  *
2580  * Returns bytes read on success, negative value otherwise.
2581  */
2582 ssize_t tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
2583 			    const int buffer_len)
2584 {
2585 	int len;
2586 	int idx;
2587 
2588 	if (!head->read)
2589 		return -EINVAL;
2590 	if (mutex_lock_interruptible(&head->io_sem))
2591 		return -EINTR;
2592 	head->read_user_buf = buffer;
2593 	head->read_user_buf_avail = buffer_len;
2594 	idx = tomoyo_read_lock();
2595 	if (tomoyo_flush(head))
2596 		/* Call the policy handler. */
2597 		do {
2598 			tomoyo_set_namespace_cursor(head);
2599 			head->read(head);
2600 		} while (tomoyo_flush(head) &&
2601 			 tomoyo_has_more_namespace(head));
2602 	tomoyo_read_unlock(idx);
2603 	len = head->read_user_buf - buffer;
2604 	mutex_unlock(&head->io_sem);
2605 	return len;
2606 }
2607 
2608 /**
2609  * tomoyo_parse_policy - Parse a policy line.
2610  *
2611  * @head: Pointer to "struct tomoyo_io_buffer".
2612  * @line: Line to parse.
2613  *
2614  * Returns 0 on success, negative value otherwise.
2615  *
2616  * Caller holds tomoyo_read_lock().
2617  */
2618 static int tomoyo_parse_policy(struct tomoyo_io_buffer *head, char *line)
2619 {
2620 	/* Delete request? */
2621 	head->w.is_delete = !strncmp(line, "delete ", 7);
2622 	if (head->w.is_delete)
2623 		memmove(line, line + 7, strlen(line + 7) + 1);
2624 	/* Selecting namespace to update. */
2625 	if (head->type == TOMOYO_EXCEPTIONPOLICY ||
2626 	    head->type == TOMOYO_PROFILE) {
2627 		if (*line == '<') {
2628 			char *cp = strchr(line, ' ');
2629 
2630 			if (cp) {
2631 				*cp++ = '\0';
2632 				head->w.ns = tomoyo_assign_namespace(line);
2633 				memmove(line, cp, strlen(cp) + 1);
2634 			} else
2635 				head->w.ns = NULL;
2636 		} else
2637 			head->w.ns = &tomoyo_kernel_namespace;
2638 		/* Don't allow updating if namespace is invalid. */
2639 		if (!head->w.ns)
2640 			return -ENOENT;
2641 	}
2642 	/* Do the update. */
2643 	return head->write(head);
2644 }
2645 
2646 /**
2647  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
2648  *
2649  * @head:       Pointer to "struct tomoyo_io_buffer".
2650  * @buffer:     Pointer to buffer to read from.
2651  * @buffer_len: Size of @buffer.
2652  *
2653  * Returns @buffer_len on success, negative value otherwise.
2654  */
2655 ssize_t tomoyo_write_control(struct tomoyo_io_buffer *head,
2656 			     const char __user *buffer, const int buffer_len)
2657 {
2658 	int error = buffer_len;
2659 	size_t avail_len = buffer_len;
2660 	char *cp0 = head->write_buf;
2661 	int idx;
2662 
2663 	if (!head->write)
2664 		return -EINVAL;
2665 	if (mutex_lock_interruptible(&head->io_sem))
2666 		return -EINTR;
2667 	head->read_user_buf_avail = 0;
2668 	idx = tomoyo_read_lock();
2669 	/* Read a line and dispatch it to the policy handler. */
2670 	while (avail_len > 0) {
2671 		char c;
2672 
2673 		if (head->w.avail >= head->writebuf_size - 1) {
2674 			const int len = head->writebuf_size * 2;
2675 			char *cp = kzalloc(len, GFP_NOFS);
2676 
2677 			if (!cp) {
2678 				error = -ENOMEM;
2679 				break;
2680 			}
2681 			memmove(cp, cp0, head->w.avail);
2682 			kfree(cp0);
2683 			head->write_buf = cp;
2684 			cp0 = cp;
2685 			head->writebuf_size = len;
2686 		}
2687 		if (get_user(c, buffer)) {
2688 			error = -EFAULT;
2689 			break;
2690 		}
2691 		buffer++;
2692 		avail_len--;
2693 		cp0[head->w.avail++] = c;
2694 		if (c != '\n')
2695 			continue;
2696 		cp0[head->w.avail - 1] = '\0';
2697 		head->w.avail = 0;
2698 		tomoyo_normalize_line(cp0);
2699 		if (!strcmp(cp0, "reset")) {
2700 			head->w.ns = &tomoyo_kernel_namespace;
2701 			head->w.domain = NULL;
2702 			memset(&head->r, 0, sizeof(head->r));
2703 			continue;
2704 		}
2705 		/* Don't allow updating policies by non manager programs. */
2706 		switch (head->type) {
2707 		case TOMOYO_PROCESS_STATUS:
2708 			/* This does not write anything. */
2709 			break;
2710 		case TOMOYO_DOMAINPOLICY:
2711 			if (tomoyo_select_domain(head, cp0))
2712 				continue;
2713 			fallthrough;
2714 		case TOMOYO_EXCEPTIONPOLICY:
2715 			if (!strcmp(cp0, "select transition_only")) {
2716 				head->r.print_transition_related_only = true;
2717 				continue;
2718 			}
2719 			fallthrough;
2720 		default:
2721 			if (!tomoyo_manager()) {
2722 				error = -EPERM;
2723 				goto out;
2724 			}
2725 		}
2726 		switch (tomoyo_parse_policy(head, cp0)) {
2727 		case -EPERM:
2728 			error = -EPERM;
2729 			goto out;
2730 		case 0:
2731 			switch (head->type) {
2732 			case TOMOYO_DOMAINPOLICY:
2733 			case TOMOYO_EXCEPTIONPOLICY:
2734 			case TOMOYO_STAT:
2735 			case TOMOYO_PROFILE:
2736 			case TOMOYO_MANAGER:
2737 				tomoyo_update_stat(TOMOYO_STAT_POLICY_UPDATES);
2738 				break;
2739 			default:
2740 				break;
2741 			}
2742 			break;
2743 		}
2744 	}
2745 out:
2746 	tomoyo_read_unlock(idx);
2747 	mutex_unlock(&head->io_sem);
2748 	return error;
2749 }
2750 
2751 /**
2752  * tomoyo_close_control - close() for /sys/kernel/security/tomoyo/ interface.
2753  *
2754  * @head: Pointer to "struct tomoyo_io_buffer".
2755  */
2756 void tomoyo_close_control(struct tomoyo_io_buffer *head)
2757 {
2758 	/*
2759 	 * If the file is /sys/kernel/security/tomoyo/query , decrement the
2760 	 * observer counter.
2761 	 */
2762 	if (head->type == TOMOYO_QUERY &&
2763 	    atomic_dec_and_test(&tomoyo_query_observers))
2764 		wake_up_all(&tomoyo_answer_wait);
2765 	tomoyo_notify_gc(head, false);
2766 }
2767 
2768 /**
2769  * tomoyo_check_profile - Check all profiles currently assigned to domains are defined.
2770  */
2771 void tomoyo_check_profile(void)
2772 {
2773 	struct tomoyo_domain_info *domain;
2774 	const int idx = tomoyo_read_lock();
2775 
2776 	tomoyo_policy_loaded = true;
2777 	pr_info("TOMOYO: 2.6.0\n");
2778 	list_for_each_entry_rcu(domain, &tomoyo_domain_list, list,
2779 				srcu_read_lock_held(&tomoyo_ss)) {
2780 		const u8 profile = domain->profile;
2781 		struct tomoyo_policy_namespace *ns = domain->ns;
2782 
2783 		if (ns->profile_version == 20110903) {
2784 			pr_info_once("Converting profile version from %u to %u.\n",
2785 				     20110903, 20150505);
2786 			ns->profile_version = 20150505;
2787 		}
2788 		if (ns->profile_version != 20150505)
2789 			pr_err("Profile version %u is not supported.\n",
2790 			       ns->profile_version);
2791 		else if (!ns->profile_ptr[profile])
2792 			pr_err("Profile %u (used by '%s') is not defined.\n",
2793 			       profile, domain->domainname->name);
2794 		else
2795 			continue;
2796 		pr_err("Userland tools for TOMOYO 2.6 must be installed and policy must be initialized.\n");
2797 		pr_err("Please see https://tomoyo.osdn.jp/2.6/ for more information.\n");
2798 		panic("STOP!");
2799 	}
2800 	tomoyo_read_unlock(idx);
2801 	pr_info("Mandatory Access Control activated.\n");
2802 }
2803 
2804 /**
2805  * tomoyo_load_builtin_policy - Load built-in policy.
2806  *
2807  * Returns nothing.
2808  */
2809 void __init tomoyo_load_builtin_policy(void)
2810 {
2811 #ifdef CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING
2812 	static char tomoyo_builtin_profile[] __initdata =
2813 		"PROFILE_VERSION=20150505\n"
2814 		"0-CONFIG={ mode=learning grant_log=no reject_log=yes }\n";
2815 	static char tomoyo_builtin_exception_policy[] __initdata =
2816 		"aggregator proc:/self/exe /proc/self/exe\n";
2817 	static char tomoyo_builtin_domain_policy[] __initdata = "";
2818 	static char tomoyo_builtin_manager[] __initdata = "";
2819 	static char tomoyo_builtin_stat[] __initdata = "";
2820 #else
2821 	/*
2822 	 * This include file is manually created and contains built-in policy
2823 	 * named "tomoyo_builtin_profile", "tomoyo_builtin_exception_policy",
2824 	 * "tomoyo_builtin_domain_policy", "tomoyo_builtin_manager",
2825 	 * "tomoyo_builtin_stat" in the form of "static char [] __initdata".
2826 	 */
2827 #include "builtin-policy.h"
2828 #endif
2829 	u8 i;
2830 	const int idx = tomoyo_read_lock();
2831 
2832 	for (i = 0; i < 5; i++) {
2833 		struct tomoyo_io_buffer head = { };
2834 		char *start = "";
2835 
2836 		switch (i) {
2837 		case 0:
2838 			start = tomoyo_builtin_profile;
2839 			head.type = TOMOYO_PROFILE;
2840 			head.write = tomoyo_write_profile;
2841 			break;
2842 		case 1:
2843 			start = tomoyo_builtin_exception_policy;
2844 			head.type = TOMOYO_EXCEPTIONPOLICY;
2845 			head.write = tomoyo_write_exception;
2846 			break;
2847 		case 2:
2848 			start = tomoyo_builtin_domain_policy;
2849 			head.type = TOMOYO_DOMAINPOLICY;
2850 			head.write = tomoyo_write_domain;
2851 			break;
2852 		case 3:
2853 			start = tomoyo_builtin_manager;
2854 			head.type = TOMOYO_MANAGER;
2855 			head.write = tomoyo_write_manager;
2856 			break;
2857 		case 4:
2858 			start = tomoyo_builtin_stat;
2859 			head.type = TOMOYO_STAT;
2860 			head.write = tomoyo_write_stat;
2861 			break;
2862 		}
2863 		while (1) {
2864 			char *end = strchr(start, '\n');
2865 
2866 			if (!end)
2867 				break;
2868 			*end = '\0';
2869 			tomoyo_normalize_line(start);
2870 			head.write_buf = start;
2871 			tomoyo_parse_policy(&head, start);
2872 			start = end + 1;
2873 		}
2874 	}
2875 	tomoyo_read_unlock(idx);
2876 #ifdef CONFIG_SECURITY_TOMOYO_OMIT_USERSPACE_LOADER
2877 	tomoyo_check_profile();
2878 #endif
2879 }
2880