/* $OpenBSD: fnmatch.c,v 1.15 2011/02/10 21:31:59 stsp Exp $ */
/* Copyright (c) 2011, VMware, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* * Neither the name of the VMware, Inc. nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL VMWARE, INC. OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/* Authored by William A. Rowe Jr. <wrowe; apache.org, vmware.com>, April 2011
*
* Derived from The Open Group Base Specifications Issue 7, IEEE Std 1003.1-2008
* as described in;
* http://pubs.opengroup.org/onlinepubs/9699919799/functions/fnmatch.html
*
* Filename pattern matches defined in section 2.13, "Pattern Matching Notation"
* from chapter 2. "Shell Command Language"
* http://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_13
* where; 1. A bracket expression starting with an unquoted <circumflex> '^'
* character CONTINUES to specify a non-matching list; 2. an explicit <period> '.'
* in a bracket expression matching list, e.g. "[.abc]" does NOT match a leading
* <period> in a filename; 3. a <left-square-bracket> '[' which does not introduce
* a valid bracket expression is treated as an ordinary character; 4. a differing
* number of consecutive slashes within pattern and string will NOT match;
* 5. a trailing '\' in FNM_ESCAPE mode is treated as an ordinary '\' character.
*
* Bracket expansion defined in section 9.3.5, "RE Bracket Expression",
* from chapter 9, "Regular Expressions"
* http://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap09.html#tag_09_03_05
* with no support for collating symbols, equivalence class expressions or
* character class expressions. A partial range expression with a leading
* hyphen following a valid range expression will match only the ordinary
* <hyphen> and the ending character (e.g. "[a-m-z]" will match characters
* 'a' through 'm', a <hyphen> '-', or a 'z').
*
* Supports BSD extensions FNM_LEADING_DIR to match pattern to the end of one
* path segment of string, and FNM_CASEFOLD to ignore alpha case.
*
* NOTE: Only POSIX/C single byte locales are correctly supported at this time.
* Notably, non-POSIX locales with FNM_CASEFOLD produce undefined results,
* particularly in ranges of mixed case (e.g. "[A-z]") or spanning alpha and
* nonalpha characters within a range.
*
* XXX comments below indicate porting required for multi-byte character sets
* and non-POSIX locale collation orders; requires mbr* APIs to track shift
* state of pattern and string (rewinding pattern and string repeatedly).
*
* Certain parts of the code assume 0x00-0x3F are unique with any MBCS (e.g.
* UTF-8, SHIFT-JIS, etc). Any implementation allowing '\' as an alternate
* path delimiter must be aware that 0x5C is NOT unique within SHIFT-JIS.
*/
#include <config.h>
#ifndef HAVE_FNMATCH
#include <sys/types.h>
#include <stdio.h>
#include <ctype.h>
#ifdef HAVE_STRING_H
# include <string.h>
#endif /* HAVE_STRING_H */
#ifdef HAVE_STRINGS_H
# include <strings.h>
#endif /* HAVE_STRINGS_H */
#include "sudo_compat.h"
#include "compat/charclass.h"
#include "compat/fnmatch.h"
#define RANGE_MATCH 1
#define RANGE_NOMATCH 0
#define RANGE_ERROR (-1)
static int
classmatch(const char *pattern, char test, int foldcase, const char **ep)
{
const char * const mismatch = pattern;
const char *colon;
struct cclass *cc;
int rval = RANGE_NOMATCH;
size_t len;
if (pattern[0] != '[' || pattern[1] != ':') {
*ep = mismatch;
return RANGE_ERROR;
}
pattern += 2;
if ((colon = strchr(pattern, ':')) == NULL || colon[1] != ']') {
*ep = mismatch;
return RANGE_ERROR;
}
*ep = colon + 2;
len = (size_t)(colon - pattern);
if (foldcase && strncmp(pattern, "upper:]", 7) == 0)
pattern = "lower:]";
for (cc = cclasses; cc->name != NULL; cc++) {
if (!strncmp(pattern, cc->name, len) && cc->name[len] == '\0') {
if (cc->isctype((unsigned char)test))
rval = RANGE_MATCH;
break;
}
}
if (cc->name == NULL) {
/* invalid character class, treat as normal text */
*ep = mismatch;
rval = RANGE_ERROR;
}
return rval;
}
/* Most MBCS/collation/case issues handled here. Wildcard '*' is not handled.
* EOS '\0' and the FNM_PATHNAME '/' delimiters are not advanced over,
* however the "\/" sequence is advanced to '/'.
*
* Both pattern and string are **char to support pointer increment of arbitrary
* multibyte characters for the given locale, in a later iteration of this code
*/
static int fnmatch_ch(const char **pattern, const char **string, int flags)
{
const char * const mismatch = *pattern;
const int nocase = !!(flags & FNM_CASEFOLD);
const int escape = !(flags & FNM_NOESCAPE);
const int slash = !!(flags & FNM_PATHNAME);
int result = FNM_NOMATCH;
const char *startch;
int negate;
if (**pattern == '[')
{
++*pattern;
/* Handle negation, either leading ! or ^ operators (never both) */
negate = ((**pattern == '!') || (**pattern == '^'));
if (negate)
++*pattern;
/* ']' is an ordinary character at the start of the range pattern */
if (**pattern == ']')
goto leadingclosebrace;
while (**pattern)
{
if (**pattern == ']') {
++*pattern;
/* XXX: Fix for MBCS character width */
++*string;
return (result ^ negate);
}
if (escape && (**pattern == '\\')) {
++*pattern;
/* Patterns must be terminated with ']', not EOS */
if (!**pattern)
break;
}
/* Patterns must be terminated with ']' not '/' */
if (slash && (**pattern == '/'))
break;
/* Match character classes. */
if (classmatch(*pattern, **string, nocase, pattern)
== RANGE_MATCH) {
result = 0;
continue;
}
if (!**pattern)
break;
leadingclosebrace:
/* Look at only well-formed range patterns;
* "x-]" is not allowed unless escaped ("x-\]")
* XXX: Fix for locale/MBCS character width
*/
if (((*pattern)[1] == '-') && ((*pattern)[2] != ']'))
{
startch = *pattern;
*pattern += (escape && ((*pattern)[2] == '\\')) ? 3 : 2;
/* NOT a properly balanced [expr] pattern, EOS terminated
* or ranges containing a slash in FNM_PATHNAME mode pattern
* fall out to to the rewind and test '[' literal code path
*/
if (!**pattern || (slash && (**pattern == '/')))
break;
/* XXX: handle locale/MBCS comparison, advance by MBCS char width */
if ((**string >= *startch) && (**string <= **pattern))
result = 0;
else if (nocase && (isupper((unsigned char)**string) ||
isupper((unsigned char)*startch) ||
isupper((unsigned char)**pattern))
&& (tolower((unsigned char)**string) >= tolower((unsigned char)*startch))
&& (tolower((unsigned char)**string) <= tolower((unsigned char)**pattern)))
result = 0;
++*pattern;
continue;
}
/* XXX: handle locale/MBCS comparison, advance by MBCS char width */
if ((**string == **pattern))
result = 0;
else if (nocase && (isupper((unsigned char)**string) ||
isupper((unsigned char)**pattern))
&& (tolower((unsigned char)**string) == tolower((unsigned char)**pattern)))
result = 0;
++*pattern;
}
/* NOT a properly balanced [expr] pattern; Rewind
* and reset result to test '[' literal
*/
*pattern = mismatch;
result = FNM_NOMATCH;
}
else if (**pattern == '?') {
/* Optimize '?' match before unescaping **pattern */
if (!**string || (slash && (**string == '/')))
return FNM_NOMATCH;
result = 0;
goto fnmatch_ch_success;
}
else if (escape && (**pattern == '\\') && (*pattern)[1]) {
++*pattern;
}
/* XXX: handle locale/MBCS comparison, advance by the MBCS char width */
if (**string == **pattern)
result = 0;
else if (nocase && (isupper((unsigned char)**string) || isupper((unsigned char)**pattern))
&& (tolower((unsigned char)**string) == tolower((unsigned char)**pattern)))
result = 0;
/* Refuse to advance over trailing slash or nulls
*/
if (!**string || !**pattern || (slash && ((**string == '/') || (**pattern == '/'))))
return result;
fnmatch_ch_success:
++*pattern;
++*string;
return result;
}
int sudo_fnmatch(const char *pattern, const char *string, int flags)
{
static const char dummystring[2] = {' ', 0};
const int escape = !(flags & FNM_NOESCAPE);
const int slash = !!(flags & FNM_PATHNAME);
const int leading_dir = !!(flags & FNM_LEADING_DIR);
const char *strendseg;
const char *dummyptr;
const char *matchptr;
int wild;
/* For '*' wild processing only; surpress 'used before initialization'
* warnings with dummy initialization values;
*/
const char *strstartseg = NULL;
const char *mismatch = NULL;
int matchlen = 0;
if (*pattern == '*')
goto firstsegment;
while (*pattern && *string)
{
/* Pre-decode "\/" which has no special significance, and
* match balanced slashes, starting a new segment pattern
*/
if (slash && escape && (*pattern == '\\') && (pattern[1] == '/'))
++pattern;
if (slash && (*pattern == '/') && (*string == '/')) {
++pattern;
++string;
}
firstsegment:
/* At the beginning of each segment, validate leading period behavior.
*/
if ((flags & FNM_PERIOD) && (*string == '.'))
{
if (*pattern == '.')
++pattern;
else if (escape && (*pattern == '\\') && (pattern[1] == '.'))
pattern += 2;
else
return FNM_NOMATCH;
++string;
}
/* Determine the end of string segment
*
* Presumes '/' character is unique, not composite in any MBCS encoding
*/
if (slash) {
strendseg = strchr(string, '/');
if (!strendseg)
strendseg = strchr(string, '\0');
}
else {
strendseg = strchr(string, '\0');
}
/* Allow pattern '*' to be consumed even with no remaining string to match
*/
while (*pattern)
{
if ((string > strendseg)
|| ((string == strendseg) && (*pattern != '*')))
break;
if (slash && ((*pattern == '/')
|| (escape && (*pattern == '\\')
&& (pattern[1] == '/'))))
break;
/* Reduce groups of '*' and '?' to n '?' matches
* followed by one '*' test for simplicity
*/
for (wild = 0; ((*pattern == '*') || (*pattern == '?')); ++pattern)
{
if (*pattern == '*') {
wild = 1;
}
else if (string < strendseg) { /* && (*pattern == '?') */
/* XXX: Advance 1 char for MBCS locale */
++string;
}
else { /* (string >= strendseg) && (*pattern == '?') */
return FNM_NOMATCH;
}
}
if (wild)
{
strstartseg = string;
mismatch = pattern;
/* Count fixed (non '*') char matches remaining in pattern
* excluding '/' (or "\/") and '*'
*/
for (matchptr = pattern, matchlen = 0; 1; ++matchlen)
{
if ((*matchptr == '\0')
|| (slash && ((*matchptr == '/')
|| (escape && (*matchptr == '\\')
&& (matchptr[1] == '/')))))
{
/* Compare precisely this many trailing string chars,
* the resulting match needs no wildcard loop
*/
/* XXX: Adjust for MBCS */
if (string + matchlen > strendseg)
return FNM_NOMATCH;
string = strendseg - matchlen;
wild = 0;
break;
}
if (*matchptr == '*')
{
/* Ensure at least this many trailing string chars remain
* for the first comparison
*/
/* XXX: Adjust for MBCS */
if (string + matchlen > strendseg)
return FNM_NOMATCH;
/* Begin first wild comparison at the current position */
break;
}
/* Skip forward in pattern by a single character match
* Use a dummy fnmatch_ch() test to count one "[range]" escape
*/
/* XXX: Adjust for MBCS */
if (escape && (*matchptr == '\\') && matchptr[1]) {
matchptr += 2;
}
else if (*matchptr == '[') {
dummyptr = dummystring;
fnmatch_ch(&matchptr, &dummyptr, flags);
}
else {
++matchptr;
}
}
}
/* Incrementally match string against the pattern
*/
while (*pattern && (string < strendseg))
{
/* Success; begin a new wild pattern search
*/
if (*pattern == '*')
break;
if (slash && ((*string == '/')
|| (*pattern == '/')
|| (escape && (*pattern == '\\')
&& (pattern[1] == '/'))))
break;
/* Compare ch's (the pattern is advanced over "\/" to the '/',
* but slashes will mismatch, and are not consumed)
*/
if (!fnmatch_ch(&pattern, &string, flags))
continue;
/* Failed to match, loop against next char offset of string segment
* until not enough string chars remain to match the fixed pattern
*/
if (wild) {
/* XXX: Advance 1 char for MBCS locale */
string = ++strstartseg;
if (string + matchlen > strendseg)
return FNM_NOMATCH;
pattern = mismatch;
continue;
}
else
return FNM_NOMATCH;
}
}
if (*string && !((slash || leading_dir) && (*string == '/')))
return FNM_NOMATCH;
if (*pattern && !(slash && ((*pattern == '/')
|| (escape && (*pattern == '\\')
&& (pattern[1] == '/')))))
return FNM_NOMATCH;
if (leading_dir && !*pattern && *string == '/')
return 0;
}
/* Where both pattern and string are at EOS, declare success
*/
if (!*string && !*pattern)
return 0;
/* pattern didn't match to the end of string */
return FNM_NOMATCH;
}
#endif /* HAVE_FNMATCH */