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mirror of https://github.com/moparisthebest/curl synced 2024-12-24 17:18:48 -05:00
curl/lib/curl_fnmatch.c
Daniel Stenberg 0b664ba968
wildcardmatch: fix heap buffer overflow in setcharset
The code would previous read beyond the end of the pattern string if the
match pattern ends with an open bracket when the default pattern
matching function is used.

Detected by OSS-Fuzz:
https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=4161

CVE-2017-8817

Bug: https://curl.haxx.se/docs/adv_2017-ae72.html
2017-11-27 08:19:34 +01:00

419 lines
11 KiB
C

/***************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.haxx.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
***************************************************************************/
#include "curl_setup.h"
#include <curl/curl.h>
#include "curl_fnmatch.h"
#include "curl_memory.h"
/* The last #include file should be: */
#include "memdebug.h"
#define CURLFNM_CHARSET_LEN (sizeof(char) * 256)
#define CURLFNM_CHSET_SIZE (CURLFNM_CHARSET_LEN + 15)
#define CURLFNM_NEGATE CURLFNM_CHARSET_LEN
#define CURLFNM_ALNUM (CURLFNM_CHARSET_LEN + 1)
#define CURLFNM_DIGIT (CURLFNM_CHARSET_LEN + 2)
#define CURLFNM_XDIGIT (CURLFNM_CHARSET_LEN + 3)
#define CURLFNM_ALPHA (CURLFNM_CHARSET_LEN + 4)
#define CURLFNM_PRINT (CURLFNM_CHARSET_LEN + 5)
#define CURLFNM_BLANK (CURLFNM_CHARSET_LEN + 6)
#define CURLFNM_LOWER (CURLFNM_CHARSET_LEN + 7)
#define CURLFNM_GRAPH (CURLFNM_CHARSET_LEN + 8)
#define CURLFNM_SPACE (CURLFNM_CHARSET_LEN + 9)
#define CURLFNM_UPPER (CURLFNM_CHARSET_LEN + 10)
typedef enum {
CURLFNM_LOOP_DEFAULT = 0,
CURLFNM_LOOP_BACKSLASH
} loop_state;
typedef enum {
CURLFNM_SCHS_DEFAULT = 0,
CURLFNM_SCHS_MAYRANGE,
CURLFNM_SCHS_MAYRANGE2,
CURLFNM_SCHS_RIGHTBR,
CURLFNM_SCHS_RIGHTBRLEFTBR
} setcharset_state;
typedef enum {
CURLFNM_PKW_INIT = 0,
CURLFNM_PKW_DDOT
} parsekey_state;
#define SETCHARSET_OK 1
#define SETCHARSET_FAIL 0
static int parsekeyword(unsigned char **pattern, unsigned char *charset)
{
parsekey_state state = CURLFNM_PKW_INIT;
#define KEYLEN 10
char keyword[KEYLEN] = { 0 };
int found = FALSE;
int i;
unsigned char *p = *pattern;
for(i = 0; !found; i++) {
char c = *p++;
if(i >= KEYLEN)
return SETCHARSET_FAIL;
switch(state) {
case CURLFNM_PKW_INIT:
if(ISALPHA(c) && ISLOWER(c))
keyword[i] = c;
else if(c == ':')
state = CURLFNM_PKW_DDOT;
else
return 0;
break;
case CURLFNM_PKW_DDOT:
if(c == ']')
found = TRUE;
else
return SETCHARSET_FAIL;
}
}
#undef KEYLEN
*pattern = p; /* move caller's pattern pointer */
if(strcmp(keyword, "digit") == 0)
charset[CURLFNM_DIGIT] = 1;
else if(strcmp(keyword, "alnum") == 0)
charset[CURLFNM_ALNUM] = 1;
else if(strcmp(keyword, "alpha") == 0)
charset[CURLFNM_ALPHA] = 1;
else if(strcmp(keyword, "xdigit") == 0)
charset[CURLFNM_XDIGIT] = 1;
else if(strcmp(keyword, "print") == 0)
charset[CURLFNM_PRINT] = 1;
else if(strcmp(keyword, "graph") == 0)
charset[CURLFNM_GRAPH] = 1;
else if(strcmp(keyword, "space") == 0)
charset[CURLFNM_SPACE] = 1;
else if(strcmp(keyword, "blank") == 0)
charset[CURLFNM_BLANK] = 1;
else if(strcmp(keyword, "upper") == 0)
charset[CURLFNM_UPPER] = 1;
else if(strcmp(keyword, "lower") == 0)
charset[CURLFNM_LOWER] = 1;
else
return SETCHARSET_FAIL;
return SETCHARSET_OK;
}
/* returns 1 (true) if pattern is OK, 0 if is bad ("p" is pattern pointer) */
static int setcharset(unsigned char **p, unsigned char *charset)
{
setcharset_state state = CURLFNM_SCHS_DEFAULT;
unsigned char rangestart = 0;
unsigned char lastchar = 0;
bool something_found = FALSE;
unsigned char c;
for(;;) {
c = **p;
if(!c)
return SETCHARSET_FAIL;
switch(state) {
case CURLFNM_SCHS_DEFAULT:
if(ISALNUM(c)) { /* ASCII value */
rangestart = c;
charset[c] = 1;
(*p)++;
state = CURLFNM_SCHS_MAYRANGE;
something_found = TRUE;
}
else if(c == ']') {
if(something_found)
return SETCHARSET_OK;
something_found = TRUE;
state = CURLFNM_SCHS_RIGHTBR;
charset[c] = 1;
(*p)++;
}
else if(c == '[') {
char c2 = *((*p) + 1);
if(c2 == ':') { /* there has to be a keyword */
(*p) += 2;
if(parsekeyword(p, charset)) {
state = CURLFNM_SCHS_DEFAULT;
}
else
return SETCHARSET_FAIL;
}
else {
charset[c] = 1;
(*p)++;
}
something_found = TRUE;
}
else if(c == '?' || c == '*') {
something_found = TRUE;
charset[c] = 1;
(*p)++;
}
else if(c == '^' || c == '!') {
if(!something_found) {
if(charset[CURLFNM_NEGATE]) {
charset[c] = 1;
something_found = TRUE;
}
else
charset[CURLFNM_NEGATE] = 1; /* negate charset */
}
else
charset[c] = 1;
(*p)++;
}
else if(c == '\\') {
c = *(++(*p));
if(ISPRINT((c))) {
something_found = TRUE;
state = CURLFNM_SCHS_MAYRANGE;
charset[c] = 1;
rangestart = c;
(*p)++;
}
else
return SETCHARSET_FAIL;
}
else {
charset[c] = 1;
(*p)++;
something_found = TRUE;
}
break;
case CURLFNM_SCHS_MAYRANGE:
if(c == '-') {
charset[c] = 1;
(*p)++;
lastchar = '-';
state = CURLFNM_SCHS_MAYRANGE2;
}
else if(c == '[') {
state = CURLFNM_SCHS_DEFAULT;
}
else if(ISALNUM(c)) {
charset[c] = 1;
(*p)++;
}
else if(c == '\\') {
c = *(++(*p));
if(ISPRINT(c)) {
charset[c] = 1;
(*p)++;
}
else
return SETCHARSET_FAIL;
}
else if(c == ']') {
return SETCHARSET_OK;
}
else
return SETCHARSET_FAIL;
break;
case CURLFNM_SCHS_MAYRANGE2:
if(c == ']') {
return SETCHARSET_OK;
}
else if(c == '\\') {
c = *(++(*p));
if(ISPRINT(c)) {
charset[c] = 1;
state = CURLFNM_SCHS_DEFAULT;
(*p)++;
}
else
return SETCHARSET_FAIL;
}
else if(c >= rangestart) {
if((ISLOWER(c) && ISLOWER(rangestart)) ||
(ISDIGIT(c) && ISDIGIT(rangestart)) ||
(ISUPPER(c) && ISUPPER(rangestart))) {
charset[lastchar] = 0;
rangestart++;
while(rangestart++ <= c)
charset[rangestart-1] = 1;
(*p)++;
state = CURLFNM_SCHS_DEFAULT;
}
else
return SETCHARSET_FAIL;
}
else
return SETCHARSET_FAIL;
break;
case CURLFNM_SCHS_RIGHTBR:
if(c == '[') {
state = CURLFNM_SCHS_RIGHTBRLEFTBR;
charset[c] = 1;
(*p)++;
}
else if(c == ']') {
return SETCHARSET_OK;
}
else if(ISPRINT(c)) {
charset[c] = 1;
(*p)++;
state = CURLFNM_SCHS_DEFAULT;
}
else
/* used 'goto fail' instead of 'return SETCHARSET_FAIL' to avoid a
* nonsense warning 'statement not reached' at end of the fnc when
* compiling on Solaris */
goto fail;
break;
case CURLFNM_SCHS_RIGHTBRLEFTBR:
if(c == ']') {
return SETCHARSET_OK;
}
else {
state = CURLFNM_SCHS_DEFAULT;
charset[c] = 1;
(*p)++;
}
break;
}
}
fail:
return SETCHARSET_FAIL;
}
static int loop(const unsigned char *pattern, const unsigned char *string)
{
loop_state state = CURLFNM_LOOP_DEFAULT;
unsigned char *p = (unsigned char *)pattern;
unsigned char *s = (unsigned char *)string;
unsigned char charset[CURLFNM_CHSET_SIZE] = { 0 };
int rc = 0;
for(;;) {
switch(state) {
case CURLFNM_LOOP_DEFAULT:
if(*p == '*') {
while(*(p + 1) == '*') /* eliminate multiple stars */
p++;
if(*s == '\0' && *(p + 1) == '\0')
return CURL_FNMATCH_MATCH;
rc = loop(p + 1, s); /* *.txt matches .txt <=> .txt matches .txt */
if(rc == CURL_FNMATCH_MATCH)
return CURL_FNMATCH_MATCH;
if(*s) /* let the star eat up one character */
s++;
else
return CURL_FNMATCH_NOMATCH;
}
else if(*p == '?') {
if(ISPRINT(*s)) {
s++;
p++;
}
else if(*s == '\0')
return CURL_FNMATCH_NOMATCH;
else
return CURL_FNMATCH_FAIL; /* cannot deal with other character */
}
else if(*p == '\0') {
if(*s == '\0')
return CURL_FNMATCH_MATCH;
return CURL_FNMATCH_NOMATCH;
}
else if(*p == '\\') {
state = CURLFNM_LOOP_BACKSLASH;
p++;
}
else if(*p == '[') {
unsigned char *pp = p + 1; /* cannot handle with pointer to register */
if(setcharset(&pp, charset)) {
int found = FALSE;
if(charset[(unsigned int)*s])
found = TRUE;
else if(charset[CURLFNM_ALNUM])
found = ISALNUM(*s);
else if(charset[CURLFNM_ALPHA])
found = ISALPHA(*s);
else if(charset[CURLFNM_DIGIT])
found = ISDIGIT(*s);
else if(charset[CURLFNM_XDIGIT])
found = ISXDIGIT(*s);
else if(charset[CURLFNM_PRINT])
found = ISPRINT(*s);
else if(charset[CURLFNM_SPACE])
found = ISSPACE(*s);
else if(charset[CURLFNM_UPPER])
found = ISUPPER(*s);
else if(charset[CURLFNM_LOWER])
found = ISLOWER(*s);
else if(charset[CURLFNM_BLANK])
found = ISBLANK(*s);
else if(charset[CURLFNM_GRAPH])
found = ISGRAPH(*s);
if(charset[CURLFNM_NEGATE])
found = !found;
if(found) {
p = pp + 1;
s++;
memset(charset, 0, CURLFNM_CHSET_SIZE);
}
else
return CURL_FNMATCH_NOMATCH;
}
else
return CURL_FNMATCH_FAIL;
}
else {
if(*p++ != *s++)
return CURL_FNMATCH_NOMATCH;
}
break;
case CURLFNM_LOOP_BACKSLASH:
if(ISPRINT(*p)) {
if(*p++ == *s++)
state = CURLFNM_LOOP_DEFAULT;
else
return CURL_FNMATCH_NOMATCH;
}
else
return CURL_FNMATCH_FAIL;
break;
}
}
}
/*
* @unittest: 1307
*/
int Curl_fnmatch(void *ptr, const char *pattern, const char *string)
{
(void)ptr; /* the argument is specified by the curl_fnmatch_callback
prototype, but not used by Curl_fnmatch() */
if(!pattern || !string) {
return CURL_FNMATCH_FAIL;
}
return loop((unsigned char *)pattern, (unsigned char *)string);
}