diff options
| -rw-r--r-- | security/tomoyo/common.c | 200 | ||||
| -rw-r--r-- | security/tomoyo/common.h | 4 |
2 files changed, 121 insertions, 83 deletions
diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c index 3c8bd8ee0b9..e0d0354008b 100644 --- a/security/tomoyo/common.c +++ b/security/tomoyo/common.c @@ -187,6 +187,8 @@ bool tomoyo_is_correct_path(const char *filename, const s8 start_type, const s8 pattern_type, const s8 end_type, const char *function) { + const char *const start = filename; + bool in_repetition = false; bool contains_pattern = false; unsigned char c; unsigned char d; @@ -212,9 +214,13 @@ bool tomoyo_is_correct_path(const char *filename, const s8 start_type, if (c == '/') goto out; } - while ((c = *filename++) != '\0') { + while (1) { + c = *filename++; + if (!c) + break; if (c == '\\') { - switch ((c = *filename++)) { + c = *filename++; + switch (c) { case '\\': /* "\\" */ continue; case '$': /* "\$" */ @@ -231,6 +237,22 @@ bool tomoyo_is_correct_path(const char *filename, const s8 start_type, break; /* Must not contain pattern */ contains_pattern = true; continue; + case '{': /* "/\{" */ + if (filename - 3 < start || + *(filename - 3) != '/') + break; + if (pattern_type == -1) + break; /* Must not contain pattern */ + contains_pattern = true; + in_repetition = true; + continue; + case '}': /* "\}/" */ + if (*filename != '/') + break; + if (!in_repetition) + break; + in_repetition = false; + continue; case '0': /* "\ooo" */ case '1': case '2': @@ -246,6 +268,8 @@ bool tomoyo_is_correct_path(const char *filename, const s8 start_type, continue; /* pattern is not \000 */ } goto out; + } else if (in_repetition && c == '/') { + goto out; } else if (tomoyo_is_invalid(c)) { goto out; } @@ -254,6 +278,8 @@ bool tomoyo_is_correct_path(const char *filename, const s8 start_type, if (!contains_pattern) goto out; } + if (in_repetition) + goto out; return true; out: printk(KERN_DEBUG "%s: Invalid pathname '%s'\n", function, @@ -360,33 +386,6 @@ struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname) } /** - * tomoyo_path_depth - Evaluate the number of '/' in a string. - * - * @pathname: The string to evaluate. - * - * Returns path depth of the string. - * - * I score 2 for each of the '/' in the @pathname - * and score 1 if the @pathname ends with '/'. - */ -static int tomoyo_path_depth(const char *pathname) -{ - int i = 0; - - if (pathname) { - const char *ep = pathname + strlen(pathname); - if (pathname < ep--) { - if (*ep != '/') - i++; - while (pathname <= ep) - if (*ep-- == '/') - i += 2; - } - } - return i; -} - -/** * tomoyo_const_part_length - Evaluate the initial length without a pattern in a token. * * @filename: The string to evaluate. @@ -444,11 +443,10 @@ void tomoyo_fill_path_info(struct tomoyo_path_info *ptr) ptr->is_dir = len && (name[len - 1] == '/'); ptr->is_patterned = (ptr->const_len < len); ptr->hash = full_name_hash(name, len); - ptr->depth = tomoyo_path_depth(name); } /** - * tomoyo_file_matches_to_pattern2 - Pattern matching without '/' character + * tomoyo_file_matches_pattern2 - Pattern matching without '/' character * and "\-" pattern. * * @filename: The start of string to check. @@ -458,10 +456,10 @@ void tomoyo_fill_path_info(struct tomoyo_path_info *ptr) * * Returns true if @filename matches @pattern, false otherwise. */ -static bool tomoyo_file_matches_to_pattern2(const char *filename, - const char *filename_end, - const char *pattern, - const char *pattern_end) +static bool tomoyo_file_matches_pattern2(const char *filename, + const char *filename_end, + const char *pattern, + const char *pattern_end) { while (filename < filename_end && pattern < pattern_end) { char c; @@ -519,7 +517,7 @@ static bool tomoyo_file_matches_to_pattern2(const char *filename, case '*': case '@': for (i = 0; i <= filename_end - filename; i++) { - if (tomoyo_file_matches_to_pattern2( + if (tomoyo_file_matches_pattern2( filename + i, filename_end, pattern + 1, pattern_end)) return true; @@ -550,7 +548,7 @@ static bool tomoyo_file_matches_to_pattern2(const char *filename, j++; } for (i = 1; i <= j; i++) { - if (tomoyo_file_matches_to_pattern2( + if (tomoyo_file_matches_pattern2( filename + i, filename_end, pattern + 1, pattern_end)) return true; @@ -567,7 +565,7 @@ static bool tomoyo_file_matches_to_pattern2(const char *filename, } /** - * tomoyo_file_matches_to_pattern - Pattern matching without without '/' character. + * tomoyo_file_matches_pattern - Pattern matching without without '/' character. * * @filename: The start of string to check. * @filename_end: The end of string to check. @@ -576,7 +574,7 @@ static bool tomoyo_file_matches_to_pattern2(const char *filename, * * Returns true if @filename matches @pattern, false otherwise. */ -static bool tomoyo_file_matches_to_pattern(const char *filename, +static bool tomoyo_file_matches_pattern(const char *filename, const char *filename_end, const char *pattern, const char *pattern_end) @@ -589,10 +587,10 @@ static bool tomoyo_file_matches_to_pattern(const char *filename, /* Split at "\-" pattern. */ if (*pattern++ != '\\' || *pattern++ != '-') continue; - result = tomoyo_file_matches_to_pattern2(filename, - filename_end, - pattern_start, - pattern - 2); + result = tomoyo_file_matches_pattern2(filename, + filename_end, + pattern_start, + pattern - 2); if (first) result = !result; if (result) @@ -600,13 +598,79 @@ static bool tomoyo_file_matches_to_pattern(const char *filename, first = false; pattern_start = pattern; } - result = tomoyo_file_matches_to_pattern2(filename, filename_end, - pattern_start, pattern_end); + result = tomoyo_file_matches_pattern2(filename, filename_end, + pattern_start, pattern_end); return first ? result : !result; } /** + * tomoyo_path_matches_pattern2 - Do pathname pattern matching. + * + * @f: The start of string to check. + * @p: The start of pattern to compare. + * + * Returns true if @f matches @p, false otherwise. + */ +static bool tomoyo_path_matches_pattern2(const char *f, const char *p) +{ + const char *f_delimiter; + const char *p_delimiter; + + while (*f && *p) { + f_delimiter = strchr(f, '/'); + if (!f_delimiter) + f_delimiter = f + strlen(f); + p_delimiter = strchr(p, '/'); + if (!p_delimiter) + p_delimiter = p + strlen(p); + if (*p == '\\' && *(p + 1) == '{') + goto recursive; + if (!tomoyo_file_matches_pattern(f, f_delimiter, p, + p_delimiter)) + return false; + f = f_delimiter; + if (*f) + f++; + p = p_delimiter; + if (*p) + p++; + } + /* Ignore trailing "\*" and "\@" in @pattern. */ + while (*p == '\\' && + (*(p + 1) == '*' || *(p + 1) == '@')) + p += 2; + return !*f && !*p; + recursive: + /* + * The "\{" pattern is permitted only after '/' character. + * This guarantees that below "*(p - 1)" is safe. + * Also, the "\}" pattern is permitted only before '/' character + * so that "\{" + "\}" pair will not break the "\-" operator. + */ + if (*(p - 1) != '/' || p_delimiter <= p + 3 || *p_delimiter != '/' || + *(p_delimiter - 1) != '}' || *(p_delimiter - 2) != '\\') + return false; /* Bad pattern. */ + do { + /* Compare current component with pattern. */ + if (!tomoyo_file_matches_pattern(f, f_delimiter, p + 2, + p_delimiter - 2)) + break; + /* Proceed to next component. */ + f = f_delimiter; + if (!*f) + break; + f++; + /* Continue comparison. */ + if (tomoyo_path_matches_pattern2(f, p_delimiter + 1)) + return true; + f_delimiter = strchr(f, '/'); + } while (f_delimiter); + return false; /* Not matched. */ +} + +/** * tomoyo_path_matches_pattern - Check whether the given filename matches the given pattern. + * * @filename: The filename to check. * @pattern: The pattern to compare. * @@ -615,24 +679,24 @@ static bool tomoyo_file_matches_to_pattern(const char *filename, * The following patterns are available. * \\ \ itself. * \ooo Octal representation of a byte. - * \* More than or equals to 0 character other than '/'. - * \@ More than or equals to 0 character other than '/' or '.'. + * \* Zero or more repetitions of characters other than '/'. + * \@ Zero or more repetitions of characters other than '/' or '.'. * \? 1 byte character other than '/'. - * \$ More than or equals to 1 decimal digit. + * \$ One or more repetitions of decimal digits. * \+ 1 decimal digit. - * \X More than or equals to 1 hexadecimal digit. + * \X One or more repetitions of hexadecimal digits. * \x 1 hexadecimal digit. - * \A More than or equals to 1 alphabet character. + * \A One or more repetitions of alphabet characters. * \a 1 alphabet character. + * * \- Subtraction operator. + * + * /\{dir\}/ '/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/ + * /dir/dir/dir/ ). */ bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename, const struct tomoyo_path_info *pattern) { - /* - if (!filename || !pattern) - return false; - */ const char *f = filename->name; const char *p = pattern->name; const int len = pattern->const_len; @@ -640,37 +704,15 @@ bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename, /* If @pattern doesn't contain pattern, I can use strcmp(). */ if (!pattern->is_patterned) return !tomoyo_pathcmp(filename, pattern); - /* Dont compare if the number of '/' differs. */ - if (filename->depth != pattern->depth) + /* Don't compare directory and non-directory. */ + if (filename->is_dir != pattern->is_dir) return false; /* Compare the initial length without patterns. */ if (strncmp(f, p, len)) return false; f += len; p += len; - /* Main loop. Compare each directory component. */ - while (*f && *p) { - const char *f_delimiter = strchr(f, '/'); - const char *p_delimiter = strchr(p, '/'); - if (!f_delimiter) - f_delimiter = f + strlen(f); - if (!p_delimiter) - p_delimiter = p + strlen(p); - if (!tomoyo_file_matches_to_pattern(f, f_delimiter, - p, p_delimiter)) - return false; - f = f_delimiter; - if (*f) - f++; - p = p_delimiter; - if (*p) - p++; - } - /* Ignore trailing "\*" and "\@" in @pattern. */ - while (*p == '\\' && - (*(p + 1) == '*' || *(p + 1) == '@')) - p += 2; - return !*f && !*p; + return tomoyo_path_matches_pattern2(f, p); } /** diff --git a/security/tomoyo/common.h b/security/tomoyo/common.h index 31df541911f..92169d29b2d 100644 --- a/security/tomoyo/common.h +++ b/security/tomoyo/common.h @@ -56,9 +56,6 @@ struct tomoyo_page_buffer { * (5) "is_patterned" is a bool which is true if "name" contains wildcard * characters, false otherwise. This allows TOMOYO to use "hash" and * strcmp() for string comparison if "is_patterned" is false. - * (6) "depth" is calculated using the number of "/" characters in "name". - * This allows TOMOYO to avoid comparing two pathnames which never match - * (e.g. whether "/var/www/html/index.html" matches "/tmp/sh-thd-\$"). */ struct tomoyo_path_info { const char *name; @@ -66,7 +63,6 @@ struct tomoyo_path_info { u16 const_len; /* = tomoyo_const_part_length(name) */ bool is_dir; /* = tomoyo_strendswith(name, "/") */ bool is_patterned; /* = tomoyo_path_contains_pattern(name) */ - u16 depth; /* = tomoyo_path_depth(name) */ }; /* |