1// SPDX-License-Identifier: GPL-2.0
   2/*
   3 * security/tomoyo/util.c
   4 *
   5 * Copyright (C) 2005-2011  NTT DATA CORPORATION
   6 */
   7
   8#include <linux/slab.h>
   9#include <linux/rculist.h>
  10
  11#include "common.h"
  12
  13/* Lock for protecting policy. */
  14DEFINE_MUTEX(tomoyo_policy_lock);
  15
  16/* Has /sbin/init started? */
  17bool tomoyo_policy_loaded;
  18
  19/*
  20 * Mapping table from "enum tomoyo_mac_index" to
  21 * "enum tomoyo_mac_category_index".
  22 */
  23const u8 tomoyo_index2category[TOMOYO_MAX_MAC_INDEX] = {
  24	/* CONFIG::file group */
  25	[TOMOYO_MAC_FILE_EXECUTE]    = TOMOYO_MAC_CATEGORY_FILE,
  26	[TOMOYO_MAC_FILE_OPEN]       = TOMOYO_MAC_CATEGORY_FILE,
  27	[TOMOYO_MAC_FILE_CREATE]     = TOMOYO_MAC_CATEGORY_FILE,
  28	[TOMOYO_MAC_FILE_UNLINK]     = TOMOYO_MAC_CATEGORY_FILE,
  29	[TOMOYO_MAC_FILE_GETATTR]    = TOMOYO_MAC_CATEGORY_FILE,
  30	[TOMOYO_MAC_FILE_MKDIR]      = TOMOYO_MAC_CATEGORY_FILE,
  31	[TOMOYO_MAC_FILE_RMDIR]      = TOMOYO_MAC_CATEGORY_FILE,
  32	[TOMOYO_MAC_FILE_MKFIFO]     = TOMOYO_MAC_CATEGORY_FILE,
  33	[TOMOYO_MAC_FILE_MKSOCK]     = TOMOYO_MAC_CATEGORY_FILE,
  34	[TOMOYO_MAC_FILE_TRUNCATE]   = TOMOYO_MAC_CATEGORY_FILE,
  35	[TOMOYO_MAC_FILE_SYMLINK]    = TOMOYO_MAC_CATEGORY_FILE,
  36	[TOMOYO_MAC_FILE_MKBLOCK]    = TOMOYO_MAC_CATEGORY_FILE,
  37	[TOMOYO_MAC_FILE_MKCHAR]     = TOMOYO_MAC_CATEGORY_FILE,
  38	[TOMOYO_MAC_FILE_LINK]       = TOMOYO_MAC_CATEGORY_FILE,
  39	[TOMOYO_MAC_FILE_RENAME]     = TOMOYO_MAC_CATEGORY_FILE,
  40	[TOMOYO_MAC_FILE_CHMOD]      = TOMOYO_MAC_CATEGORY_FILE,
  41	[TOMOYO_MAC_FILE_CHOWN]      = TOMOYO_MAC_CATEGORY_FILE,
  42	[TOMOYO_MAC_FILE_CHGRP]      = TOMOYO_MAC_CATEGORY_FILE,
  43	[TOMOYO_MAC_FILE_IOCTL]      = TOMOYO_MAC_CATEGORY_FILE,
  44	[TOMOYO_MAC_FILE_CHROOT]     = TOMOYO_MAC_CATEGORY_FILE,
  45	[TOMOYO_MAC_FILE_MOUNT]      = TOMOYO_MAC_CATEGORY_FILE,
  46	[TOMOYO_MAC_FILE_UMOUNT]     = TOMOYO_MAC_CATEGORY_FILE,
  47	[TOMOYO_MAC_FILE_PIVOT_ROOT] = TOMOYO_MAC_CATEGORY_FILE,
  48	/* CONFIG::network group */
  49	[TOMOYO_MAC_NETWORK_INET_STREAM_BIND]       =
  50	TOMOYO_MAC_CATEGORY_NETWORK,
  51	[TOMOYO_MAC_NETWORK_INET_STREAM_LISTEN]     =
  52	TOMOYO_MAC_CATEGORY_NETWORK,
  53	[TOMOYO_MAC_NETWORK_INET_STREAM_CONNECT]    =
  54	TOMOYO_MAC_CATEGORY_NETWORK,
  55	[TOMOYO_MAC_NETWORK_INET_DGRAM_BIND]        =
  56	TOMOYO_MAC_CATEGORY_NETWORK,
  57	[TOMOYO_MAC_NETWORK_INET_DGRAM_SEND]        =
  58	TOMOYO_MAC_CATEGORY_NETWORK,
  59	[TOMOYO_MAC_NETWORK_INET_RAW_BIND]          =
  60	TOMOYO_MAC_CATEGORY_NETWORK,
  61	[TOMOYO_MAC_NETWORK_INET_RAW_SEND]          =
  62	TOMOYO_MAC_CATEGORY_NETWORK,
  63	[TOMOYO_MAC_NETWORK_UNIX_STREAM_BIND]       =
  64	TOMOYO_MAC_CATEGORY_NETWORK,
  65	[TOMOYO_MAC_NETWORK_UNIX_STREAM_LISTEN]     =
  66	TOMOYO_MAC_CATEGORY_NETWORK,
  67	[TOMOYO_MAC_NETWORK_UNIX_STREAM_CONNECT]    =
  68	TOMOYO_MAC_CATEGORY_NETWORK,
  69	[TOMOYO_MAC_NETWORK_UNIX_DGRAM_BIND]        =
  70	TOMOYO_MAC_CATEGORY_NETWORK,
  71	[TOMOYO_MAC_NETWORK_UNIX_DGRAM_SEND]        =
  72	TOMOYO_MAC_CATEGORY_NETWORK,
  73	[TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_BIND]    =
  74	TOMOYO_MAC_CATEGORY_NETWORK,
  75	[TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_LISTEN]  =
  76	TOMOYO_MAC_CATEGORY_NETWORK,
  77	[TOMOYO_MAC_NETWORK_UNIX_SEQPACKET_CONNECT] =
  78	TOMOYO_MAC_CATEGORY_NETWORK,
  79	/* CONFIG::misc group */
  80	[TOMOYO_MAC_ENVIRON]         = TOMOYO_MAC_CATEGORY_MISC,
  81};
  82
  83/**
  84 * tomoyo_convert_time - Convert time_t to YYYY/MM/DD hh/mm/ss.
  85 *
  86 * @time64: Seconds since 1970/01/01 00:00:00.
  87 * @stamp:  Pointer to "struct tomoyo_time".
  88 *
  89 * Returns nothing.
  90 */
  91void tomoyo_convert_time(time64_t time64, struct tomoyo_time *stamp)
  92{
  93	struct tm tm;
  94
  95	time64_to_tm(time64, 0, &tm);
  96	stamp->sec = tm.tm_sec;
  97	stamp->min = tm.tm_min;
  98	stamp->hour = tm.tm_hour;
  99	stamp->day = tm.tm_mday;
 100	stamp->month = tm.tm_mon + 1;
 101	stamp->year = tm.tm_year + 1900;
 102}
 103
 104/**
 105 * tomoyo_permstr - Find permission keywords.
 106 *
 107 * @string: String representation for permissions in foo/bar/buz format.
 108 * @keyword: Keyword to find from @string/
 109 *
 110 * Returns true if @keyword was found in @string, false otherwise.
 111 *
 112 * This function assumes that strncmp(w1, w2, strlen(w1)) != 0 if w1 != w2.
 113 */
 114bool tomoyo_permstr(const char *string, const char *keyword)
 115{
 116	const char *cp = strstr(string, keyword);
 117
 118	if (cp)
 119		return cp == string || *(cp - 1) == '/';
 120	return false;
 121}
 122
 123/**
 124 * tomoyo_read_token - Read a word from a line.
 125 *
 126 * @param: Pointer to "struct tomoyo_acl_param".
 127 *
 128 * Returns a word on success, "" otherwise.
 129 *
 130 * To allow the caller to skip NULL check, this function returns "" rather than
 131 * NULL if there is no more words to read.
 132 */
 133char *tomoyo_read_token(struct tomoyo_acl_param *param)
 134{
 135	char *pos = param->data;
 136	char *del = strchr(pos, ' ');
 137
 138	if (del)
 139		*del++ = '\0';
 140	else
 141		del = pos + strlen(pos);
 142	param->data = del;
 143	return pos;
 144}
 145
 146static bool tomoyo_correct_path2(const char *filename, const size_t len);
 147
 148/**
 149 * tomoyo_get_domainname - Read a domainname from a line.
 150 *
 151 * @param: Pointer to "struct tomoyo_acl_param".
 152 *
 153 * Returns a domainname on success, NULL otherwise.
 154 */
 155const struct tomoyo_path_info *tomoyo_get_domainname
 156(struct tomoyo_acl_param *param)
 157{
 158	char *start = param->data;
 159	char *pos = start;
 160
 161	while (*pos) {
 162		if (*pos++ != ' ' ||
 163		    tomoyo_correct_path2(pos, strchrnul(pos, ' ') - pos))
 164			continue;
 165		*(pos - 1) = '\0';
 166		break;
 167	}
 168	param->data = pos;
 169	if (tomoyo_correct_domain(start))
 170		return tomoyo_get_name(start);
 171	return NULL;
 172}
 173
 174/**
 175 * tomoyo_parse_ulong - Parse an "unsigned long" value.
 176 *
 177 * @result: Pointer to "unsigned long".
 178 * @str:    Pointer to string to parse.
 179 *
 180 * Returns one of values in "enum tomoyo_value_type".
 181 *
 182 * The @src is updated to point the first character after the value
 183 * on success.
 184 */
 185u8 tomoyo_parse_ulong(unsigned long *result, char **str)
 186{
 187	const char *cp = *str;
 188	char *ep;
 189	int base = 10;
 190
 191	if (*cp == '0') {
 192		char c = *(cp + 1);
 193
 194		if (c == 'x' || c == 'X') {
 195			base = 16;
 196			cp += 2;
 197		} else if (c >= '0' && c <= '7') {
 198			base = 8;
 199			cp++;
 200		}
 201	}
 202	*result = simple_strtoul(cp, &ep, base);
 203	if (cp == ep)
 204		return TOMOYO_VALUE_TYPE_INVALID;
 205	*str = ep;
 206	switch (base) {
 207	case 16:
 208		return TOMOYO_VALUE_TYPE_HEXADECIMAL;
 209	case 8:
 210		return TOMOYO_VALUE_TYPE_OCTAL;
 211	default:
 212		return TOMOYO_VALUE_TYPE_DECIMAL;
 213	}
 214}
 215
 216/**
 217 * tomoyo_print_ulong - Print an "unsigned long" value.
 218 *
 219 * @buffer:     Pointer to buffer.
 220 * @buffer_len: Size of @buffer.
 221 * @value:      An "unsigned long" value.
 222 * @type:       Type of @value.
 223 *
 224 * Returns nothing.
 225 */
 226void tomoyo_print_ulong(char *buffer, const int buffer_len,
 227			const unsigned long value, const u8 type)
 228{
 229	if (type == TOMOYO_VALUE_TYPE_DECIMAL)
 230		snprintf(buffer, buffer_len, "%lu", value);
 231	else if (type == TOMOYO_VALUE_TYPE_OCTAL)
 232		snprintf(buffer, buffer_len, "0%lo", value);
 233	else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL)
 234		snprintf(buffer, buffer_len, "0x%lX", value);
 235	else
 236		snprintf(buffer, buffer_len, "type(%u)", type);
 237}
 238
 239/**
 240 * tomoyo_parse_name_union - Parse a tomoyo_name_union.
 241 *
 242 * @param: Pointer to "struct tomoyo_acl_param".
 243 * @ptr:   Pointer to "struct tomoyo_name_union".
 244 *
 245 * Returns true on success, false otherwise.
 246 */
 247bool tomoyo_parse_name_union(struct tomoyo_acl_param *param,
 248			     struct tomoyo_name_union *ptr)
 249{
 250	char *filename;
 251
 252	if (param->data[0] == '@') {
 253		param->data++;
 254		ptr->group = tomoyo_get_group(param, TOMOYO_PATH_GROUP);
 255		return ptr->group != NULL;
 256	}
 257	filename = tomoyo_read_token(param);
 258	if (!tomoyo_correct_word(filename))
 259		return false;
 260	ptr->filename = tomoyo_get_name(filename);
 261	return ptr->filename != NULL;
 262}
 263
 264/**
 265 * tomoyo_parse_number_union - Parse a tomoyo_number_union.
 266 *
 267 * @param: Pointer to "struct tomoyo_acl_param".
 268 * @ptr:   Pointer to "struct tomoyo_number_union".
 269 *
 270 * Returns true on success, false otherwise.
 271 */
 272bool tomoyo_parse_number_union(struct tomoyo_acl_param *param,
 273			       struct tomoyo_number_union *ptr)
 274{
 275	char *data;
 276	u8 type;
 277	unsigned long v;
 278
 279	memset(ptr, 0, sizeof(*ptr));
 280	if (param->data[0] == '@') {
 281		param->data++;
 282		ptr->group = tomoyo_get_group(param, TOMOYO_NUMBER_GROUP);
 283		return ptr->group != NULL;
 284	}
 285	data = tomoyo_read_token(param);
 286	type = tomoyo_parse_ulong(&v, &data);
 287	if (type == TOMOYO_VALUE_TYPE_INVALID)
 288		return false;
 289	ptr->values[0] = v;
 290	ptr->value_type[0] = type;
 291	if (!*data) {
 292		ptr->values[1] = v;
 293		ptr->value_type[1] = type;
 294		return true;
 295	}
 296	if (*data++ != '-')
 297		return false;
 298	type = tomoyo_parse_ulong(&v, &data);
 299	if (type == TOMOYO_VALUE_TYPE_INVALID || *data || ptr->values[0] > v)
 300		return false;
 301	ptr->values[1] = v;
 302	ptr->value_type[1] = type;
 303	return true;
 304}
 305
 306/**
 307 * tomoyo_byte_range - Check whether the string is a \ooo style octal value.
 308 *
 309 * @str: Pointer to the string.
 310 *
 311 * Returns true if @str is a \ooo style octal value, false otherwise.
 312 *
 313 * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
 314 * This function verifies that \ooo is in valid range.
 315 */
 316static inline bool tomoyo_byte_range(const char *str)
 317{
 318	return *str >= '0' && *str++ <= '3' &&
 319		*str >= '0' && *str++ <= '7' &&
 320		*str >= '0' && *str <= '7';
 321}
 322
 323/**
 324 * tomoyo_alphabet_char - Check whether the character is an alphabet.
 325 *
 326 * @c: The character to check.
 327 *
 328 * Returns true if @c is an alphabet character, false otherwise.
 329 */
 330static inline bool tomoyo_alphabet_char(const char c)
 331{
 332	return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
 333}
 334
 335/**
 336 * tomoyo_make_byte - Make byte value from three octal characters.
 337 *
 338 * @c1: The first character.
 339 * @c2: The second character.
 340 * @c3: The third character.
 341 *
 342 * Returns byte value.
 343 */
 344static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
 345{
 346	return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
 347}
 348
 349/**
 350 * tomoyo_valid - Check whether the character is a valid char.
 351 *
 352 * @c: The character to check.
 353 *
 354 * Returns true if @c is a valid character, false otherwise.
 355 */
 356static inline bool tomoyo_valid(const unsigned char c)
 357{
 358	return c > ' ' && c < 127;
 359}
 360
 361/**
 362 * tomoyo_invalid - Check whether the character is an invalid char.
 363 *
 364 * @c: The character to check.
 365 *
 366 * Returns true if @c is an invalid character, false otherwise.
 367 */
 368static inline bool tomoyo_invalid(const unsigned char c)
 369{
 370	return c && (c <= ' ' || c >= 127);
 371}
 372
 373/**
 374 * tomoyo_str_starts - Check whether the given string starts with the given keyword.
 375 *
 376 * @src:  Pointer to pointer to the string.
 377 * @find: Pointer to the keyword.
 378 *
 379 * Returns true if @src starts with @find, false otherwise.
 380 *
 381 * The @src is updated to point the first character after the @find
 382 * if @src starts with @find.
 383 */
 384bool tomoyo_str_starts(char **src, const char *find)
 385{
 386	const int len = strlen(find);
 387	char *tmp = *src;
 388
 389	if (strncmp(tmp, find, len))
 390		return false;
 391	tmp += len;
 392	*src = tmp;
 393	return true;
 394}
 395
 396/**
 397 * tomoyo_normalize_line - Format string.
 398 *
 399 * @buffer: The line to normalize.
 400 *
 401 * Leading and trailing whitespaces are removed.
 402 * Multiple whitespaces are packed into single space.
 403 *
 404 * Returns nothing.
 405 */
 406void tomoyo_normalize_line(unsigned char *buffer)
 407{
 408	unsigned char *sp = buffer;
 409	unsigned char *dp = buffer;
 410	bool first = true;
 411
 412	while (tomoyo_invalid(*sp))
 413		sp++;
 414	while (*sp) {
 415		if (!first)
 416			*dp++ = ' ';
 417		first = false;
 418		while (tomoyo_valid(*sp))
 419			*dp++ = *sp++;
 420		while (tomoyo_invalid(*sp))
 421			sp++;
 422	}
 423	*dp = '\0';
 424}
 425
 426/**
 427 * tomoyo_correct_word2 - Validate a string.
 428 *
 429 * @string: The string to check. Maybe non-'\0'-terminated.
 430 * @len:    Length of @string.
 431 *
 432 * Check whether the given string follows the naming rules.
 433 * Returns true if @string follows the naming rules, false otherwise.
 434 */
 435static bool tomoyo_correct_word2(const char *string, size_t len)
 436{
 437	u8 recursion = 20;
 438	const char *const start = string;
 439	bool in_repetition = false;
 440
 441	if (!len)
 442		goto out;
 443	while (len--) {
 444		unsigned char c = *string++;
 445
 446		if (c == '\\') {
 447			if (!len--)
 448				goto out;
 449			c = *string++;
 450			if (c >= '0' && c <= '3') {
 451				unsigned char d;
 452				unsigned char e;
 453
 454				if (!len-- || !len--)
 455					goto out;
 456				d = *string++;
 457				e = *string++;
 458				if (d < '0' || d > '7' || e < '0' || e > '7')
 459					goto out;
 460				c = tomoyo_make_byte(c, d, e);
 461				if (c <= ' ' || c >= 127)
 462					continue;
 463				goto out;
 464			}
 465			switch (c) {
 466			case '\\':  /* "\\" */
 467			case '+':   /* "\+" */
 468			case '?':   /* "\?" */
 469			case 'x':   /* "\x" */
 470			case 'a':   /* "\a" */
 471			case '-':   /* "\-" */
 472				continue;
 473			}
 474			if (!recursion--)
 475				goto out;
 476			switch (c) {
 477			case '*':   /* "\*" */
 478			case '@':   /* "\@" */
 479			case '$':   /* "\$" */
 480			case 'X':   /* "\X" */
 481			case 'A':   /* "\A" */
 482				continue;
 483			case '{':   /* "/\{" */
 484				if (string - 3 < start || *(string - 3) != '/')
 485					goto out;
 486				in_repetition = true;
 487				continue;
 488			case '}':   /* "\}/" */
 489				if (*string != '/')
 490					goto out;
 491				if (!in_repetition)
 492					goto out;
 493				in_repetition = false;
 494				continue;
 495			}
 496			goto out;
 497		} else if (in_repetition && c == '/') {
 498			goto out;
 499		} else if (c <= ' ' || c >= 127) {
 500			goto out;
 501		}
 502	}
 503	if (in_repetition)
 504		goto out;
 505	return true;
 506 out:
 507	return false;
 508}
 509
 510/**
 511 * tomoyo_correct_word - Validate a string.
 512 *
 513 * @string: The string to check.
 514 *
 515 * Check whether the given string follows the naming rules.
 516 * Returns true if @string follows the naming rules, false otherwise.
 517 */
 518bool tomoyo_correct_word(const char *string)
 519{
 520	return tomoyo_correct_word2(string, strlen(string));
 521}
 522
 523/**
 524 * tomoyo_correct_path2 - Check whether the given pathname follows the naming rules.
 525 *
 526 * @filename: The pathname to check.
 527 * @len:      Length of @filename.
 528 *
 529 * Returns true if @filename follows the naming rules, false otherwise.
 530 */
 531static bool tomoyo_correct_path2(const char *filename, const size_t len)
 532{
 533	const char *cp1 = memchr(filename, '/', len);
 534	const char *cp2 = memchr(filename, '.', len);
 535
 536	return cp1 && (!cp2 || (cp1 < cp2)) && tomoyo_correct_word2(filename, len);
 537}
 538
 539/**
 540 * tomoyo_correct_path - Validate a pathname.
 541 *
 542 * @filename: The pathname to check.
 543 *
 544 * Check whether the given pathname follows the naming rules.
 545 * Returns true if @filename follows the naming rules, false otherwise.
 546 */
 547bool tomoyo_correct_path(const char *filename)
 548{
 549	return tomoyo_correct_path2(filename, strlen(filename));
 550}
 551
 552/**
 553 * tomoyo_correct_domain - Check whether the given domainname follows the naming rules.
 554 *
 555 * @domainname: The domainname to check.
 556 *
 557 * Returns true if @domainname follows the naming rules, false otherwise.
 558 */
 559bool tomoyo_correct_domain(const unsigned char *domainname)
 560{
 561	if (!domainname || !tomoyo_domain_def(domainname))
 562		return false;
 563	domainname = strchr(domainname, ' ');
 564	if (!domainname++)
 565		return true;
 566	while (1) {
 567		const unsigned char *cp = strchr(domainname, ' ');
 568
 569		if (!cp)
 570			break;
 571		if (!tomoyo_correct_path2(domainname, cp - domainname))
 572			return false;
 573		domainname = cp + 1;
 574	}
 575	return tomoyo_correct_path(domainname);
 576}
 577
 578/**
 579 * tomoyo_domain_def - Check whether the given token can be a domainname.
 580 *
 581 * @buffer: The token to check.
 582 *
 583 * Returns true if @buffer possibly be a domainname, false otherwise.
 584 */
 585bool tomoyo_domain_def(const unsigned char *buffer)
 586{
 587	const unsigned char *cp;
 588	int len;
 589
 590	if (*buffer != '<')
 591		return false;
 592	cp = strchr(buffer, ' ');
 593	if (!cp)
 594		len = strlen(buffer);
 595	else
 596		len = cp - buffer;
 597	if (buffer[len - 1] != '>' ||
 598	    !tomoyo_correct_word2(buffer + 1, len - 2))
 599		return false;
 600	return true;
 601}
 602
 603/**
 604 * tomoyo_find_domain - Find a domain by the given name.
 605 *
 606 * @domainname: The domainname to find.
 607 *
 608 * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
 609 *
 610 * Caller holds tomoyo_read_lock().
 611 */
 612struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
 613{
 614	struct tomoyo_domain_info *domain;
 615	struct tomoyo_path_info name;
 616
 617	name.name = domainname;
 618	tomoyo_fill_path_info(&name);
 619	list_for_each_entry_rcu(domain, &tomoyo_domain_list, list,
 620				srcu_read_lock_held(&tomoyo_ss)) {
 621		if (!domain->is_deleted &&
 622		    !tomoyo_pathcmp(&name, domain->domainname))
 623			return domain;
 624	}
 625	return NULL;
 626}
 627
 628/**
 629 * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
 630 *
 631 * @filename: The string to evaluate.
 632 *
 633 * Returns the initial length without a pattern in @filename.
 634 */
 635static int tomoyo_const_part_length(const char *filename)
 636{
 637	char c;
 638	int len = 0;
 639
 640	if (!filename)
 641		return 0;
 642	while ((c = *filename++) != '\0') {
 643		if (c != '\\') {
 644			len++;
 645			continue;
 646		}
 647		c = *filename++;
 648		switch (c) {
 649		case '\\':  /* "\\" */
 650			len += 2;
 651			continue;
 652		case '0':   /* "\ooo" */
 653		case '1':
 654		case '2':
 655		case '3':
 656			c = *filename++;
 657			if (c < '0' || c > '7')
 658				break;
 659			c = *filename++;
 660			if (c < '0' || c > '7')
 661				break;
 662			len += 4;
 663			continue;
 664		}
 665		break;
 666	}
 667	return len;
 668}
 669
 670/**
 671 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
 672 *
 673 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
 674 *
 675 * The caller sets "struct tomoyo_path_info"->name.
 676 */
 677void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
 678{
 679	const char *name = ptr->name;
 680	const int len = strlen(name);
 681
 682	ptr->const_len = tomoyo_const_part_length(name);
 683	ptr->is_dir = len && (name[len - 1] == '/');
 684	ptr->is_patterned = (ptr->const_len < len);
 685	ptr->hash = full_name_hash(NULL, name, len);
 686}
 687
 688/**
 689 * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern.
 690 *
 691 * @filename:     The start of string to check.
 692 * @filename_end: The end of string to check.
 693 * @pattern:      The start of pattern to compare.
 694 * @pattern_end:  The end of pattern to compare.
 695 *
 696 * Returns true if @filename matches @pattern, false otherwise.
 697 */
 698static bool tomoyo_file_matches_pattern2(const char *filename,
 699					 const char *filename_end,
 700					 const char *pattern,
 701					 const char *pattern_end)
 702{
 703	while (filename < filename_end && pattern < pattern_end) {
 704		char c;
 705		int i;
 706		int j;
 707
 708		if (*pattern != '\\') {
 709			if (*filename++ != *pattern++)
 710				return false;
 711			continue;
 712		}
 713		c = *filename;
 714		pattern++;
 715		switch (*pattern) {
 716		case '?':
 717			if (c == '/') {
 718				return false;
 719			} else if (c == '\\') {
 720				if (filename[1] == '\\')
 721					filename++;
 722				else if (tomoyo_byte_range(filename + 1))
 723					filename += 3;
 724				else
 725					return false;
 726			}
 727			break;
 728		case '\\':
 729			if (c != '\\')
 730				return false;
 731			if (*++filename != '\\')
 732				return false;
 733			break;
 734		case '+':
 735			if (!isdigit(c))
 736				return false;
 737			break;
 738		case 'x':
 739			if (!isxdigit(c))
 740				return false;
 741			break;
 742		case 'a':
 743			if (!tomoyo_alphabet_char(c))
 744				return false;
 745			break;
 746		case '0':
 747		case '1':
 748		case '2':
 749		case '3':
 750			if (c == '\\' && tomoyo_byte_range(filename + 1)
 751			    && strncmp(filename + 1, pattern, 3) == 0) {
 752				filename += 3;
 753				pattern += 2;
 754				break;
 755			}
 756			return false; /* Not matched. */
 757		case '*':
 758		case '@':
 759			for (i = 0; i <= filename_end - filename; i++) {
 760				if (tomoyo_file_matches_pattern2(
 761						    filename + i, filename_end,
 762						    pattern + 1, pattern_end))
 763					return true;
 764				c = filename[i];
 765				if (c == '.' && *pattern == '@')
 766					break;
 767				if (c != '\\')
 768					continue;
 769				if (filename[i + 1] == '\\')
 770					i++;
 771				else if (tomoyo_byte_range(filename + i + 1))
 772					i += 3;
 773				else
 774					break; /* Bad pattern. */
 775			}
 776			return false; /* Not matched. */
 777		default:
 778			j = 0;
 779			c = *pattern;
 780			if (c == '$') {
 781				while (isdigit(filename[j]))
 782					j++;
 783			} else if (c == 'X') {
 784				while (isxdigit(filename[j]))
 785					j++;
 786			} else if (c == 'A') {
 787				while (tomoyo_alphabet_char(filename[j]))
 788					j++;
 789			}
 790			for (i = 1; i <= j; i++) {
 791				if (tomoyo_file_matches_pattern2(
 792						    filename + i, filename_end,
 793						    pattern + 1, pattern_end))
 794					return true;
 795			}
 796			return false; /* Not matched or bad pattern. */
 797		}
 798		filename++;
 799		pattern++;
 800	}
 801	while (*pattern == '\\' &&
 802	       (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
 803		pattern += 2;
 804	return filename == filename_end && pattern == pattern_end;
 805}
 806
 807/**
 808 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
 809 *
 810 * @filename:     The start of string to check.
 811 * @filename_end: The end of string to check.
 812 * @pattern:      The start of pattern to compare.
 813 * @pattern_end:  The end of pattern to compare.
 814 *
 815 * Returns true if @filename matches @pattern, false otherwise.
 816 */
 817static bool tomoyo_file_matches_pattern(const char *filename,
 818					const char *filename_end,
 819					const char *pattern,
 820					const char *pattern_end)
 821{
 822	const char *pattern_start = pattern;
 823	bool first = true;
 824	bool result;
 825
 826	while (pattern < pattern_end - 1) {
 827		/* Split at "\-" pattern. */
 828		if (*pattern++ != '\\' || *pattern++ != '-')
 829			continue;
 830		result = tomoyo_file_matches_pattern2(filename,
 831						      filename_end,
 832						      pattern_start,
 833						      pattern - 2);
 834		if (first)
 835			result = !result;
 836		if (result)
 837			return false;
 838		first = false;
 839		pattern_start = pattern;
 840	}
 841	result = tomoyo_file_matches_pattern2(filename, filename_end,
 842					      pattern_start, pattern_end);
 843	return first ? result : !result;
 844}
 845
 846/**
 847 * tomoyo_path_matches_pattern2 - Do pathname pattern matching.
 848 *
 849 * @f: The start of string to check.
 850 * @p: The start of pattern to compare.
 851 *
 852 * Returns true if @f matches @p, false otherwise.
 853 */
 854static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
 855{
 856	const char *f_delimiter;
 857	const char *p_delimiter;
 858
 859	while (*f && *p) {
 860		f_delimiter = strchr(f, '/');
 861		if (!f_delimiter)
 862			f_delimiter = f + strlen(f);
 863		p_delimiter = strchr(p, '/');
 864		if (!p_delimiter)
 865			p_delimiter = p + strlen(p);
 866		if (*p == '\\' && *(p + 1) == '{')
 867			goto recursive;
 868		if (!tomoyo_file_matches_pattern(f, f_delimiter, p,
 869						 p_delimiter))
 870			return false;
 871		f = f_delimiter;
 872		if (*f)
 873			f++;
 874		p = p_delimiter;
 875		if (*p)
 876			p++;
 877	}
 878	/* Ignore trailing "\*" and "\@" in @pattern. */
 879	while (*p == '\\' &&
 880	       (*(p + 1) == '*' || *(p + 1) == '@'))
 881		p += 2;
 882	return !*f && !*p;
 883 recursive:
 884	/*
 885	 * The "\{" pattern is permitted only after '/' character.
 886	 * This guarantees that below "*(p - 1)" is safe.
 887	 * Also, the "\}" pattern is permitted only before '/' character
 888	 * so that "\{" + "\}" pair will not break the "\-" operator.
 889	 */
 890	if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
 891	    *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
 892		return false; /* Bad pattern. */
 893	do {
 894		/* Compare current component with pattern. */
 895		if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2,
 896						 p_delimiter - 2))
 897			break;
 898		/* Proceed to next component. */
 899		f = f_delimiter;
 900		if (!*f)
 901			break;
 902		f++;
 903		/* Continue comparison. */
 904		if (tomoyo_path_matches_pattern2(f, p_delimiter + 1))
 905			return true;
 906		f_delimiter = strchr(f, '/');
 907	} while (f_delimiter);
 908	return false; /* Not matched. */
 909}
 910
 911/**
 912 * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
 913 *
 914 * @filename: The filename to check.
 915 * @pattern:  The pattern to compare.
 916 *
 917 * Returns true if matches, false otherwise.
 918 *
 919 * The following patterns are available.
 920 *   \\     \ itself.
 921 *   \ooo   Octal representation of a byte.
 922 *   \*     Zero or more repetitions of characters other than '/'.
 923 *   \@     Zero or more repetitions of characters other than '/' or '.'.
 924 *   \?     1 byte character other than '/'.
 925 *   \$     One or more repetitions of decimal digits.
 926 *   \+     1 decimal digit.
 927 *   \X     One or more repetitions of hexadecimal digits.
 928 *   \x     1 hexadecimal digit.
 929 *   \A     One or more repetitions of alphabet characters.
 930 *   \a     1 alphabet character.
 931 *
 932 *   \-     Subtraction operator.
 933 *
 934 *   /\{dir\}/   '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
 935 *               /dir/dir/dir/ ).
 936 */
 937bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
 938				 const struct tomoyo_path_info *pattern)
 939{
 940	const char *f = filename->name;
 941	const char *p = pattern->name;
 942	const int len = pattern->const_len;
 943
 944	/* If @pattern doesn't contain pattern, I can use strcmp(). */
 945	if (!pattern->is_patterned)
 946		return !tomoyo_pathcmp(filename, pattern);
 947	/* Don't compare directory and non-directory. */
 948	if (filename->is_dir != pattern->is_dir)
 949		return false;
 950	/* Compare the initial length without patterns. */
 951	if (strncmp(f, p, len))
 952		return false;
 953	f += len;
 954	p += len;
 955	return tomoyo_path_matches_pattern2(f, p);
 956}
 957
 958/**
 959 * tomoyo_get_exe - Get tomoyo_realpath() of current process.
 960 *
 961 * Returns the tomoyo_realpath() of current process on success, NULL otherwise.
 962 *
 963 * This function uses kzalloc(), so the caller must call kfree()
 964 * if this function didn't return NULL.
 965 */
 966const char *tomoyo_get_exe(void)
 967{
 968	struct file *exe_file;
 969	const char *cp;
 970	struct mm_struct *mm = current->mm;
 971
 972	if (!mm)
 973		return NULL;
 974	exe_file = get_mm_exe_file(mm);
 975	if (!exe_file)
 976		return NULL;
 977
 978	cp = tomoyo_realpath_from_path(&exe_file->f_path);
 979	fput(exe_file);
 980	return cp;
 981}
 982
 983/**
 984 * tomoyo_get_mode - Get MAC mode.
 985 *
 986 * @ns:      Pointer to "struct tomoyo_policy_namespace".
 987 * @profile: Profile number.
 988 * @index:   Index number of functionality.
 989 *
 990 * Returns mode.
 991 */
 992int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
 993		    const u8 index)
 994{
 995	u8 mode;
 996	struct tomoyo_profile *p;
 997
 998	if (!tomoyo_policy_loaded)
 999		return TOMOYO_CONFIG_DISABLED;
1000	p = tomoyo_profile(ns, profile);
1001	mode = p->config[index];
1002	if (mode == TOMOYO_CONFIG_USE_DEFAULT)
1003		mode = p->config[tomoyo_index2category[index]
1004				 + TOMOYO_MAX_MAC_INDEX];
1005	if (mode == TOMOYO_CONFIG_USE_DEFAULT)
1006		mode = p->default_config;
1007	return mode & 3;
1008}
1009
1010/**
1011 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
1012 *
1013 * @r:      Pointer to "struct tomoyo_request_info" to initialize.
1014 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
1015 * @index:  Index number of functionality.
1016 *
1017 * Returns mode.
1018 */
1019int tomoyo_init_request_info(struct tomoyo_request_info *r,
1020			     struct tomoyo_domain_info *domain, const u8 index)
1021{
1022	u8 profile;
1023
1024	memset(r, 0, sizeof(*r));
1025	if (!domain)
1026		domain = tomoyo_domain();
1027	r->domain = domain;
1028	profile = domain->profile;
1029	r->profile = profile;
1030	r->type = index;
1031	r->mode = tomoyo_get_mode(domain->ns, profile, index);
1032	return r->mode;
1033}
1034
1035/**
1036 * tomoyo_domain_quota_is_ok - Check for domain's quota.
1037 *
1038 * @r: Pointer to "struct tomoyo_request_info".
1039 *
1040 * Returns true if the domain is not exceeded quota, false otherwise.
1041 *
1042 * Caller holds tomoyo_read_lock().
1043 */
1044bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
1045{
1046	unsigned int count = 0;
1047	struct tomoyo_domain_info *domain = r->domain;
1048	struct tomoyo_acl_info *ptr;
1049
1050	if (r->mode != TOMOYO_CONFIG_LEARNING)
1051		return false;
1052	if (!domain)
1053		return true;
1054	if (READ_ONCE(domain->flags[TOMOYO_DIF_QUOTA_WARNED]))
1055		return false;
1056	list_for_each_entry_rcu(ptr, &domain->acl_info_list, list,
1057				srcu_read_lock_held(&tomoyo_ss)) {
1058		u16 perm;
 
1059
1060		if (ptr->is_deleted)
1061			continue;
1062		/*
1063		 * Reading perm bitmap might race with tomoyo_merge_*() because
1064		 * caller does not hold tomoyo_policy_lock mutex. But exceeding
1065		 * max_learning_entry parameter by a few entries does not harm.
1066		 */
1067		switch (ptr->type) {
1068		case TOMOYO_TYPE_PATH_ACL:
1069			perm = data_race(container_of(ptr, struct tomoyo_path_acl, head)->perm);
1070			break;
1071		case TOMOYO_TYPE_PATH2_ACL:
1072			perm = data_race(container_of(ptr, struct tomoyo_path2_acl, head)->perm);
1073			break;
1074		case TOMOYO_TYPE_PATH_NUMBER_ACL:
1075			perm = data_race(container_of(ptr, struct tomoyo_path_number_acl, head)
1076				  ->perm);
1077			break;
1078		case TOMOYO_TYPE_MKDEV_ACL:
1079			perm = data_race(container_of(ptr, struct tomoyo_mkdev_acl, head)->perm);
1080			break;
1081		case TOMOYO_TYPE_INET_ACL:
1082			perm = data_race(container_of(ptr, struct tomoyo_inet_acl, head)->perm);
1083			break;
1084		case TOMOYO_TYPE_UNIX_ACL:
1085			perm = data_race(container_of(ptr, struct tomoyo_unix_acl, head)->perm);
1086			break;
1087		case TOMOYO_TYPE_MANUAL_TASK_ACL:
1088			perm = 0;
1089			break;
1090		default:
1091			perm = 1;
1092		}
1093		count += hweight16(perm);
 
 
1094	}
1095	if (count < tomoyo_profile(domain->ns, domain->profile)->
1096	    pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
1097		return true;
1098	WRITE_ONCE(domain->flags[TOMOYO_DIF_QUOTA_WARNED], true);
1099	/* r->granted = false; */
1100	tomoyo_write_log(r, "%s", tomoyo_dif[TOMOYO_DIF_QUOTA_WARNED]);
 
1101#ifndef CONFIG_SECURITY_TOMOYO_INSECURE_BUILTIN_SETTING
1102	pr_warn("WARNING: Domain '%s' has too many ACLs to hold. Stopped learning mode.\n",
1103		domain->domainname->name);
1104#endif
 
1105	return false;
1106}