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TOMOYO: Add recursive directory matching operator support.
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TOMOYO 1.7.1 has recursive directory matching operator support.
I want to add it to TOMOYO for Linux 2.6.33 .
----------
[PATCH] TOMOYO: Add recursive directory matching operator support.

This patch introduces new operator /\{dir\}/ which matches
'/' + 'One or more repetitions of dir/' (e.g. /dir/ /dir/dir/ /dir/dir/dir/ ).

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Acked-by: John Johansen <john.johansen@canonical.com>
Signed-off-by: James Morris <jmorris@namei.org>
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Tetsuo Handa authored and James Morris committed Nov 25, 2009
1 parent b3a222e commit 7539cf4
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Showing 2 changed files with 121 additions and 83 deletions.
200 changes: 121 additions & 79 deletions security/tomoyo/common.c
View file
Original file line number Diff line number Diff line change
Expand Up @@ -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;
Expand All @@ -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 '$': /* "\$" */
Expand All @@ -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':
Expand All @@ -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;
}
Expand All @@ -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,
Expand Down Expand Up @@ -359,33 +385,6 @@ struct tomoyo_domain_info *tomoyo_find_domain(const char *domainname)
return NULL;
}

/**
* 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.
*
Expand Down Expand Up @@ -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.
Expand All @@ -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;
Expand Down Expand Up @@ -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;
Expand Down Expand Up @@ -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;
Expand All @@ -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.
Expand All @@ -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)
Expand All @@ -589,24 +587,90 @@ 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)
return false;
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.
*
Expand All @@ -615,62 +679,40 @@ 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;

/* 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);
}

/**
Expand Down
4 changes: 0 additions & 4 deletions security/tomoyo/common.h
View file
Original file line number Diff line number Diff line change
Expand Up @@ -56,17 +56,13 @@ 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;
u32 hash; /* = full_name_hash(name, strlen(name)) */
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) */
};

/*
Expand Down

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