2 * security/tomoyo/util.c
4 * Utility functions for TOMOYO.
6 * Copyright (C) 2005-2010 NTT DATA CORPORATION
9 #include <linux/slab.h>
12 /* Lock for protecting policy. */
13 DEFINE_MUTEX(tomoyo_policy_lock);
15 /* Has /sbin/init started? */
16 bool tomoyo_policy_loaded;
19 * tomoyo_permstr - Find permission keywords.
21 * @string: String representation for permissions in foo/bar/buz format.
22 * @keyword: Keyword to find from @string/
24 * Returns ture if @keyword was found in @string, false otherwise.
26 * This function assumes that strncmp(w1, w2, strlen(w1)) != 0 if w1 != w2.
28 bool tomoyo_permstr(const char *string, const char *keyword)
30 const char *cp = strstr(string, keyword);
32 return cp == string || *(cp - 1) == '/';
37 * tomoyo_read_token - Read a word from a line.
39 * @param: Pointer to "struct tomoyo_acl_param".
41 * Returns a word on success, "" otherwise.
43 * To allow the caller to skip NULL check, this function returns "" rather than
44 * NULL if there is no more words to read.
46 char *tomoyo_read_token(struct tomoyo_acl_param *param)
48 char *pos = param->data;
49 char *del = strchr(pos, ' ');
53 del = pos + strlen(pos);
59 * tomoyo_parse_ulong - Parse an "unsigned long" value.
61 * @result: Pointer to "unsigned long".
62 * @str: Pointer to string to parse.
64 * Returns one of values in "enum tomoyo_value_type".
66 * The @src is updated to point the first character after the value
69 static u8 tomoyo_parse_ulong(unsigned long *result, char **str)
71 const char *cp = *str;
76 if (c == 'x' || c == 'X') {
79 } else if (c >= '0' && c <= '7') {
84 *result = simple_strtoul(cp, &ep, base);
86 return TOMOYO_VALUE_TYPE_INVALID;
90 return TOMOYO_VALUE_TYPE_HEXADECIMAL;
92 return TOMOYO_VALUE_TYPE_OCTAL;
94 return TOMOYO_VALUE_TYPE_DECIMAL;
99 * tomoyo_print_ulong - Print an "unsigned long" value.
101 * @buffer: Pointer to buffer.
102 * @buffer_len: Size of @buffer.
103 * @value: An "unsigned long" value.
104 * @type: Type of @value.
108 void tomoyo_print_ulong(char *buffer, const int buffer_len,
109 const unsigned long value, const u8 type)
111 if (type == TOMOYO_VALUE_TYPE_DECIMAL)
112 snprintf(buffer, buffer_len, "%lu", value);
113 else if (type == TOMOYO_VALUE_TYPE_OCTAL)
114 snprintf(buffer, buffer_len, "0%lo", value);
115 else if (type == TOMOYO_VALUE_TYPE_HEXADECIMAL)
116 snprintf(buffer, buffer_len, "0x%lX", value);
118 snprintf(buffer, buffer_len, "type(%u)", type);
122 * tomoyo_parse_name_union - Parse a tomoyo_name_union.
124 * @param: Pointer to "struct tomoyo_acl_param".
125 * @ptr: Pointer to "struct tomoyo_name_union".
127 * Returns true on success, false otherwise.
129 bool tomoyo_parse_name_union(struct tomoyo_acl_param *param,
130 struct tomoyo_name_union *ptr)
133 if (param->data[0] == '@') {
135 ptr->group = tomoyo_get_group(param, TOMOYO_PATH_GROUP);
136 return ptr->group != NULL;
138 filename = tomoyo_read_token(param);
139 if (!tomoyo_correct_word(filename))
141 ptr->filename = tomoyo_get_name(filename);
142 return ptr->filename != NULL;
146 * tomoyo_parse_number_union - Parse a tomoyo_number_union.
148 * @param: Pointer to "struct tomoyo_acl_param".
149 * @ptr: Pointer to "struct tomoyo_number_union".
151 * Returns true on success, false otherwise.
153 bool tomoyo_parse_number_union(struct tomoyo_acl_param *param,
154 struct tomoyo_number_union *ptr)
159 memset(ptr, 0, sizeof(*ptr));
160 if (param->data[0] == '@') {
162 ptr->group = tomoyo_get_group(param, TOMOYO_NUMBER_GROUP);
163 return ptr->group != NULL;
165 data = tomoyo_read_token(param);
166 type = tomoyo_parse_ulong(&v, &data);
167 if (type == TOMOYO_VALUE_TYPE_INVALID)
170 ptr->value_type[0] = type;
173 ptr->value_type[1] = type;
178 type = tomoyo_parse_ulong(&v, &data);
179 if (type == TOMOYO_VALUE_TYPE_INVALID || *data || ptr->values[0] > v)
182 ptr->value_type[1] = type;
187 * tomoyo_byte_range - Check whether the string is a \ooo style octal value.
189 * @str: Pointer to the string.
191 * Returns true if @str is a \ooo style octal value, false otherwise.
193 * TOMOYO uses \ooo style representation for 0x01 - 0x20 and 0x7F - 0xFF.
194 * This function verifies that \ooo is in valid range.
196 static inline bool tomoyo_byte_range(const char *str)
198 return *str >= '0' && *str++ <= '3' &&
199 *str >= '0' && *str++ <= '7' &&
200 *str >= '0' && *str <= '7';
204 * tomoyo_alphabet_char - Check whether the character is an alphabet.
206 * @c: The character to check.
208 * Returns true if @c is an alphabet character, false otherwise.
210 static inline bool tomoyo_alphabet_char(const char c)
212 return (c >= 'A' && c <= 'Z') || (c >= 'a' && c <= 'z');
216 * tomoyo_make_byte - Make byte value from three octal characters.
218 * @c1: The first character.
219 * @c2: The second character.
220 * @c3: The third character.
222 * Returns byte value.
224 static inline u8 tomoyo_make_byte(const u8 c1, const u8 c2, const u8 c3)
226 return ((c1 - '0') << 6) + ((c2 - '0') << 3) + (c3 - '0');
230 * tomoyo_valid - Check whether the character is a valid char.
232 * @c: The character to check.
234 * Returns true if @c is a valid character, false otherwise.
236 static inline bool tomoyo_valid(const unsigned char c)
238 return c > ' ' && c < 127;
242 * tomoyo_invalid - Check whether the character is an invalid char.
244 * @c: The character to check.
246 * Returns true if @c is an invalid character, false otherwise.
248 static inline bool tomoyo_invalid(const unsigned char c)
250 return c && (c <= ' ' || c >= 127);
254 * tomoyo_str_starts - Check whether the given string starts with the given keyword.
256 * @src: Pointer to pointer to the string.
257 * @find: Pointer to the keyword.
259 * Returns true if @src starts with @find, false otherwise.
261 * The @src is updated to point the first character after the @find
262 * if @src starts with @find.
264 bool tomoyo_str_starts(char **src, const char *find)
266 const int len = strlen(find);
269 if (strncmp(tmp, find, len))
277 * tomoyo_normalize_line - Format string.
279 * @buffer: The line to normalize.
281 * Leading and trailing whitespaces are removed.
282 * Multiple whitespaces are packed into single space.
286 void tomoyo_normalize_line(unsigned char *buffer)
288 unsigned char *sp = buffer;
289 unsigned char *dp = buffer;
292 while (tomoyo_invalid(*sp))
298 while (tomoyo_valid(*sp))
300 while (tomoyo_invalid(*sp))
307 * tomoyo_correct_word2 - Validate a string.
309 * @string: The string to check. May be non-'\0'-terminated.
310 * @len: Length of @string.
312 * Check whether the given string follows the naming rules.
313 * Returns true if @string follows the naming rules, false otherwise.
315 static bool tomoyo_correct_word2(const char *string, size_t len)
317 const char *const start = string;
318 bool in_repetition = false;
331 case '\\': /* "\\" */
344 case '{': /* "/\{" */
345 if (string - 3 < start || *(string - 3) != '/')
347 in_repetition = true;
349 case '}': /* "\}/" */
354 in_repetition = false;
356 case '0': /* "\ooo" */
360 if (!len-- || !len--)
364 if (d < '0' || d > '7' || e < '0' || e > '7')
366 c = tomoyo_make_byte(c, d, e);
367 if (tomoyo_invalid(c))
368 continue; /* pattern is not \000 */
371 } else if (in_repetition && c == '/') {
373 } else if (tomoyo_invalid(c)) {
385 * tomoyo_correct_word - Validate a string.
387 * @string: The string to check.
389 * Check whether the given string follows the naming rules.
390 * Returns true if @string follows the naming rules, false otherwise.
392 bool tomoyo_correct_word(const char *string)
394 return tomoyo_correct_word2(string, strlen(string));
398 * tomoyo_correct_path - Validate a pathname.
400 * @filename: The pathname to check.
402 * Check whether the given pathname follows the naming rules.
403 * Returns true if @filename follows the naming rules, false otherwise.
405 bool tomoyo_correct_path(const char *filename)
407 return *filename == '/' && tomoyo_correct_word(filename);
411 * tomoyo_correct_domain - Check whether the given domainname follows the naming rules.
413 * @domainname: The domainname to check.
415 * Returns true if @domainname follows the naming rules, false otherwise.
417 bool tomoyo_correct_domain(const unsigned char *domainname)
419 if (!domainname || !tomoyo_domain_def(domainname))
421 domainname = strchr(domainname, ' ');
425 const unsigned char *cp = strchr(domainname, ' ');
428 if (*domainname != '/' ||
429 !tomoyo_correct_word2(domainname, cp - domainname))
433 return tomoyo_correct_path(domainname);
437 * tomoyo_domain_def - Check whether the given token can be a domainname.
439 * @buffer: The token to check.
441 * Returns true if @buffer possibly be a domainname, false otherwise.
443 bool tomoyo_domain_def(const unsigned char *buffer)
445 const unsigned char *cp;
449 cp = strchr(buffer, ' ');
451 len = strlen(buffer);
454 if (buffer[len - 1] != '>' ||
455 !tomoyo_correct_word2(buffer + 1, len - 2))
461 * tomoyo_find_domain - Find a domain by the given name.
463 * @domainname: The domainname to find.
465 * Returns pointer to "struct tomoyo_domain_info" if found, NULL otherwise.
467 * Caller holds tomoyo_read_lock().
469 struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
471 struct tomoyo_domain_info *domain;
472 struct tomoyo_path_info name;
474 name.name = domainname;
475 tomoyo_fill_path_info(&name);
476 list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
477 if (!domain->is_deleted &&
478 !tomoyo_pathcmp(&name, domain->domainname))
485 * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token.
487 * @filename: The string to evaluate.
489 * Returns the initial length without a pattern in @filename.
491 static int tomoyo_const_part_length(const char *filename)
498 while ((c = *filename++) != '\0') {
505 case '\\': /* "\\" */
508 case '0': /* "\ooo" */
513 if (c < '0' || c > '7')
516 if (c < '0' || c > '7')
527 * tomoyo_fill_path_info - Fill in "struct tomoyo_path_info" members.
529 * @ptr: Pointer to "struct tomoyo_path_info" to fill in.
531 * The caller sets "struct tomoyo_path_info"->name.
533 void tomoyo_fill_path_info(struct tomoyo_path_info *ptr)
535 const char *name = ptr->name;
536 const int len = strlen(name);
538 ptr->const_len = tomoyo_const_part_length(name);
539 ptr->is_dir = len && (name[len - 1] == '/');
540 ptr->is_patterned = (ptr->const_len < len);
541 ptr->hash = full_name_hash(name, len);
545 * tomoyo_file_matches_pattern2 - Pattern matching without '/' character and "\-" pattern.
547 * @filename: The start of string to check.
548 * @filename_end: The end of string to check.
549 * @pattern: The start of pattern to compare.
550 * @pattern_end: The end of pattern to compare.
552 * Returns true if @filename matches @pattern, false otherwise.
554 static bool tomoyo_file_matches_pattern2(const char *filename,
555 const char *filename_end,
557 const char *pattern_end)
559 while (filename < filename_end && pattern < pattern_end) {
561 if (*pattern != '\\') {
562 if (*filename++ != *pattern++)
574 } else if (c == '\\') {
575 if (filename[1] == '\\')
577 else if (tomoyo_byte_range(filename + 1))
586 if (*++filename != '\\')
598 if (!tomoyo_alphabet_char(c))
605 if (c == '\\' && tomoyo_byte_range(filename + 1)
606 && strncmp(filename + 1, pattern, 3) == 0) {
611 return false; /* Not matched. */
614 for (i = 0; i <= filename_end - filename; i++) {
615 if (tomoyo_file_matches_pattern2(
616 filename + i, filename_end,
617 pattern + 1, pattern_end))
620 if (c == '.' && *pattern == '@')
624 if (filename[i + 1] == '\\')
626 else if (tomoyo_byte_range(filename + i + 1))
629 break; /* Bad pattern. */
631 return false; /* Not matched. */
636 while (isdigit(filename[j]))
638 } else if (c == 'X') {
639 while (isxdigit(filename[j]))
641 } else if (c == 'A') {
642 while (tomoyo_alphabet_char(filename[j]))
645 for (i = 1; i <= j; i++) {
646 if (tomoyo_file_matches_pattern2(
647 filename + i, filename_end,
648 pattern + 1, pattern_end))
651 return false; /* Not matched or bad pattern. */
656 while (*pattern == '\\' &&
657 (*(pattern + 1) == '*' || *(pattern + 1) == '@'))
659 return filename == filename_end && pattern == pattern_end;
663 * tomoyo_file_matches_pattern - Pattern matching without '/' character.
665 * @filename: The start of string to check.
666 * @filename_end: The end of string to check.
667 * @pattern: The start of pattern to compare.
668 * @pattern_end: The end of pattern to compare.
670 * Returns true if @filename matches @pattern, false otherwise.
672 static bool tomoyo_file_matches_pattern(const char *filename,
673 const char *filename_end,
675 const char *pattern_end)
677 const char *pattern_start = pattern;
681 while (pattern < pattern_end - 1) {
682 /* Split at "\-" pattern. */
683 if (*pattern++ != '\\' || *pattern++ != '-')
685 result = tomoyo_file_matches_pattern2(filename,
694 pattern_start = pattern;
696 result = tomoyo_file_matches_pattern2(filename, filename_end,
697 pattern_start, pattern_end);
698 return first ? result : !result;
702 * tomoyo_path_matches_pattern2 - Do pathname pattern matching.
704 * @f: The start of string to check.
705 * @p: The start of pattern to compare.
707 * Returns true if @f matches @p, false otherwise.
709 static bool tomoyo_path_matches_pattern2(const char *f, const char *p)
711 const char *f_delimiter;
712 const char *p_delimiter;
715 f_delimiter = strchr(f, '/');
717 f_delimiter = f + strlen(f);
718 p_delimiter = strchr(p, '/');
720 p_delimiter = p + strlen(p);
721 if (*p == '\\' && *(p + 1) == '{')
723 if (!tomoyo_file_matches_pattern(f, f_delimiter, p,
733 /* Ignore trailing "\*" and "\@" in @pattern. */
735 (*(p + 1) == '*' || *(p + 1) == '@'))
740 * The "\{" pattern is permitted only after '/' character.
741 * This guarantees that below "*(p - 1)" is safe.
742 * Also, the "\}" pattern is permitted only before '/' character
743 * so that "\{" + "\}" pair will not break the "\-" operator.
745 if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' ||
746 *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\')
747 return false; /* Bad pattern. */
749 /* Compare current component with pattern. */
750 if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2,
753 /* Proceed to next component. */
758 /* Continue comparison. */
759 if (tomoyo_path_matches_pattern2(f, p_delimiter + 1))
761 f_delimiter = strchr(f, '/');
762 } while (f_delimiter);
763 return false; /* Not matched. */
767 * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern.
769 * @filename: The filename to check.
770 * @pattern: The pattern to compare.
772 * Returns true if matches, false otherwise.
774 * The following patterns are available.
776 * \ooo Octal representation of a byte.
777 * \* Zero or more repetitions of characters other than '/'.
778 * \@ Zero or more repetitions of characters other than '/' or '.'.
779 * \? 1 byte character other than '/'.
780 * \$ One or more repetitions of decimal digits.
781 * \+ 1 decimal digit.
782 * \X One or more repetitions of hexadecimal digits.
783 * \x 1 hexadecimal digit.
784 * \A One or more repetitions of alphabet characters.
785 * \a 1 alphabet character.
787 * \- Subtraction operator.
789 * /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/
792 bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
793 const struct tomoyo_path_info *pattern)
795 const char *f = filename->name;
796 const char *p = pattern->name;
797 const int len = pattern->const_len;
799 /* If @pattern doesn't contain pattern, I can use strcmp(). */
800 if (!pattern->is_patterned)
801 return !tomoyo_pathcmp(filename, pattern);
802 /* Don't compare directory and non-directory. */
803 if (filename->is_dir != pattern->is_dir)
805 /* Compare the initial length without patterns. */
806 if (strncmp(f, p, len))
810 return tomoyo_path_matches_pattern2(f, p);
814 * tomoyo_get_exe - Get tomoyo_realpath() of current process.
816 * Returns the tomoyo_realpath() of current process on success, NULL otherwise.
818 * This function uses kzalloc(), so the caller must call kfree()
819 * if this function didn't return NULL.
821 const char *tomoyo_get_exe(void)
823 struct mm_struct *mm = current->mm;
824 struct vm_area_struct *vma;
825 const char *cp = NULL;
829 down_read(&mm->mmap_sem);
830 for (vma = mm->mmap; vma; vma = vma->vm_next) {
831 if ((vma->vm_flags & VM_EXECUTABLE) && vma->vm_file) {
832 cp = tomoyo_realpath_from_path(&vma->vm_file->f_path);
836 up_read(&mm->mmap_sem);
841 * tomoyo_get_mode - Get MAC mode.
843 * @ns: Pointer to "struct tomoyo_policy_namespace".
844 * @profile: Profile number.
845 * @index: Index number of functionality.
849 int tomoyo_get_mode(const struct tomoyo_policy_namespace *ns, const u8 profile,
853 const u8 category = TOMOYO_MAC_CATEGORY_FILE;
854 if (!tomoyo_policy_loaded)
855 return TOMOYO_CONFIG_DISABLED;
856 mode = tomoyo_profile(ns, profile)->config[index];
857 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
858 mode = tomoyo_profile(ns, profile)->config[category];
859 if (mode == TOMOYO_CONFIG_USE_DEFAULT)
860 mode = tomoyo_profile(ns, profile)->default_config;
865 * tomoyo_init_request_info - Initialize "struct tomoyo_request_info" members.
867 * @r: Pointer to "struct tomoyo_request_info" to initialize.
868 * @domain: Pointer to "struct tomoyo_domain_info". NULL for tomoyo_domain().
869 * @index: Index number of functionality.
873 int tomoyo_init_request_info(struct tomoyo_request_info *r,
874 struct tomoyo_domain_info *domain, const u8 index)
877 memset(r, 0, sizeof(*r));
879 domain = tomoyo_domain();
881 profile = domain->profile;
882 r->profile = profile;
884 r->mode = tomoyo_get_mode(domain->ns, profile, index);
889 * tomoyo_domain_quota_is_ok - Check for domain's quota.
891 * @r: Pointer to "struct tomoyo_request_info".
893 * Returns true if the domain is not exceeded quota, false otherwise.
895 * Caller holds tomoyo_read_lock().
897 bool tomoyo_domain_quota_is_ok(struct tomoyo_request_info *r)
899 unsigned int count = 0;
900 struct tomoyo_domain_info *domain = r->domain;
901 struct tomoyo_acl_info *ptr;
903 if (r->mode != TOMOYO_CONFIG_LEARNING)
907 list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
913 case TOMOYO_TYPE_PATH_ACL:
914 perm = container_of(ptr, struct tomoyo_path_acl, head)
917 case TOMOYO_TYPE_PATH2_ACL:
918 perm = container_of(ptr, struct tomoyo_path2_acl, head)
921 case TOMOYO_TYPE_PATH_NUMBER_ACL:
922 perm = container_of(ptr, struct tomoyo_path_number_acl,
925 case TOMOYO_TYPE_MKDEV_ACL:
926 perm = container_of(ptr, struct tomoyo_mkdev_acl,
932 for (i = 0; i < 16; i++)
936 if (count < tomoyo_profile(domain->ns, domain->profile)->
937 pref[TOMOYO_PREF_MAX_LEARNING_ENTRY])
939 if (!domain->quota_warned) {
940 domain->quota_warned = true;
941 printk(KERN_WARNING "TOMOYO-WARNING: "
942 "Domain '%s' has too many ACLs to hold. "
943 "Stopped learning mode.\n", domain->domainname->name);