src/regex.c - haproxy - Gitiles

 /*
  * Regex and string management functions.
  *
  * Copyright 2000-2010 Willy Tarreau <w@1wt.eu>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version
  * 2 of the License, or (at your option) any later version.
  *
  */

 #include <ctype.h>
 #include <stdlib.h>
 #include <string.h>

 #include <common/config.h>
 #include <common/defaults.h>
 #include <common/regex.h>
 #include <common/standard.h>
 #include <proto/log.h>

 /* regex trash buffer used by various regex tests */
 regmatch_t pmatch[MAX_MATCH];  /* rm_so, rm_eo for regular expressions */

 int exp_replace(char *dst, unsigned int dst_size, char *src, const char *str, const regmatch_t *matches)
 {
 	char *old_dst = dst;
 	char* dst_end = dst + dst_size;

 	while (*str) {
 		if (*str == '\\') {
 			str++;
 			if (!*str)
 				return -1;

 			if (isdigit((unsigned char)*str)) {
 				int len, num;

 				num = *str - '0';
 				str++;

 				if (matches[num].rm_eo > -1 && matches[num].rm_so > -1) {
 					len = matches[num].rm_eo - matches[num].rm_so;

 					if (dst + len >= dst_end)
 						return -1;

 					memcpy(dst, src + matches[num].rm_so, len);
 					dst += len;
 				}

 			} else if (*str == 'x') {
 				unsigned char hex1, hex2;
 				str++;

 				if (!*str)
 					return -1;

 				hex1 = toupper(*str++) - '0';

 				if (!*str)
 					return -1;

 				hex2 = toupper(*str++) - '0';

 				if (hex1 > 9) hex1 -= 'A' - '9' - 1;
 				if (hex2 > 9) hex2 -= 'A' - '9' - 1;

 				if (dst >= dst_end)
 					return -1;

 				*dst++ = (hex1<<4) + hex2;
 			} else {
 				if (dst >= dst_end)
 					return -1;

 				*dst++ = *str++;
 			}
 		} else {
 			if (dst >= dst_end)
 				return -1;

 			*dst++ = *str++;
 		}
 	}
 	if (dst >= dst_end)
 		return -1;

 	*dst = '\0';
 	return dst - old_dst;
 }

 /* returns NULL if the replacement string <str> is valid, or the pointer to the first error */
 const char *check_replace_string(const char *str)
 {
 	const char *err = NULL;
 	while (*str) {
 		if (*str == '\\') {
 			err = str; /* in case of a backslash, we return the pointer to it */
 			str++;
 			if (!*str)
 				return err;
 			else if (isdigit((unsigned char)*str))
 				err = NULL;
 			else if (*str == 'x') {
 				str++;
 				if (!ishex(*str))
 					return err;
 				str++;
 				if (!ishex(*str))
 					return err;
 				err = NULL;
 			}
 			else {
 				Warning("'\\%c' : deprecated use of a backslash before something not '\\','x' or a digit.\n", *str);
 				err = NULL;
 			}
 		}
 		str++;
 	}
 	return err;
 }


 /* returns the pointer to an error in the replacement string, or NULL if OK */
 const char *chain_regex(struct hdr_exp **head, struct my_regex *preg,
 			int action, const char *replace, void *cond)
 {
 	struct hdr_exp *exp;

 	if (replace != NULL) {
 		const char *err;
 		err = check_replace_string(replace);
 		if (err)
 			return err;
 	}

 	while (*head != NULL)
 		head = &(*head)->next;

 	exp = calloc(1, sizeof(struct hdr_exp));

 	exp->preg = preg;
 	exp->replace = replace;
 	exp->action = action;
 	exp->cond = cond;
 	*head = exp;

 	return NULL;
 }

 /* This function apply regex. It take const null terminated char as input.
  * If the function doesn't match, it returns false, else it returns true.
  * When it is compiled with JIT, this function execute strlen on the subject.
  */
 int regex_exec_match(const struct my_regex *preg, const char *subject,
                      size_t nmatch, regmatch_t pmatch[]) {
 #if defined(USE_PCRE) || defined(USE_PCRE_JIT)
 	int ret;
 	int matches[MAX_MATCH * 3];
 	int enmatch;
 	int i;

 	/* Silently limit the number of allowed matches. max
 	 * match i the maximum value for match, in fact this
 	 * limit is not applyied.
 	 */
 	enmatch = nmatch;
 	if (enmatch > MAX_MATCH)
 		enmatch = MAX_MATCH;

 	/* The value returned by pcre_exec() is one more than the highest numbered
 	 * pair that has been set. For example, if two substrings have been captured,
 	 * the returned value is 3. If there are no capturing subpatterns, the return
 	 * value from a successful match is 1, indicating that just the first pair of
 	 * offsets has been set.
 	 *
 	 * It seems that this function returns 0 if it detect more matches than avalaible
 	 * space in the matches array.
 	 */
 	ret = pcre_exec(preg->reg, preg->extra, subject, strlen(subject), 0, 0, matches, enmatch * 3);
 	if (ret < 0)
 		return 0;

 	if (ret == 0)
 		ret = enmatch;

 	for (i=0; i<nmatch; i++) {
 		/* Copy offset. */
 		if (i < ret) {
 			pmatch[i].rm_so = matches[(i*2)];
 			pmatch[i].rm_eo = matches[(i*2)+1];
 			continue;
 		}
 		/* Set the unmatvh flag (-1). */
 		pmatch[i].rm_so = -1;
 		pmatch[i].rm_eo = -1;
 	}
 	return 1;
 #else
 	int match;
 	match = regexec(&preg->regex, subject, nmatch, pmatch, 0);
 	if (match == REG_NOMATCH)
 		return 0;
 	return 1;
 #endif
 }

 /* This function apply regex. It take a "char *" ans length as input. The
  * <subject> can be modified during the processing. If the function doesn't
  * match, it returns false, else it returns true.
  * When it is compiled with standard POSIX regex or PCRE, this function add
  * a temporary null chracters at the end of the <subject>. The <subject> must
  * have a real length of <length> + 1.
  */
 int regex_exec_match2(const struct my_regex *preg, char *subject, int length,
                       size_t nmatch, regmatch_t pmatch[]) {
 #if defined(USE_PCRE) || defined(USE_PCRE_JIT)
 	int ret;
 	int matches[MAX_MATCH * 3];
 	int enmatch;
 	int i;

 	/* Silently limit the number of allowed matches. max
 	 * match i the maximum value for match, in fact this
 	 * limit is not applyied.
 	 */
 	enmatch = nmatch;
 	if (enmatch > MAX_MATCH)
 		enmatch = MAX_MATCH;

 	/* The value returned by pcre_exec() is one more than the highest numbered
 	 * pair that has been set. For example, if two substrings have been captured,
 	 * the returned value is 3. If there are no capturing subpatterns, the return
 	 * value from a successful match is 1, indicating that just the first pair of
 	 * offsets has been set.
 	 *
 	 * It seems that this function returns 0 if it detect more matches than avalaible
 	 * space in the matches array.
 	 */
 	ret = pcre_exec(preg->reg, preg->extra, subject, length, 0, 0, matches, enmatch * 3);
 	if (ret < 0)
 		return 0;

 	if (ret == 0)
 		ret = enmatch;

 	for (i=0; i<nmatch; i++) {
 		/* Copy offset. */
 		if (i < ret) {
 			pmatch[i].rm_so = matches[(i*2)];
 			pmatch[i].rm_eo = matches[(i*2)+1];
 			continue;
 		}
 		/* Set the unmatvh flag (-1). */
 		pmatch[i].rm_so = -1;
 		pmatch[i].rm_eo = -1;
 	}
 	return 1;
 #else
 	char old_char = subject[length];
 	int match;
 	subject[length] = 0;
 	match = regexec(&preg->regex, subject, nmatch, pmatch, 0);
 	subject[length] = old_char;
 	if (match == REG_NOMATCH)
 		return 0;
 	return 1;
 #endif
 }

 int regex_comp(const char *str, struct my_regex *regex, int cs, int cap, char **err)
 {
 #if defined(USE_PCRE) || defined(USE_PCRE_JIT)
 	int flags = 0;
 	const char *error;
 	int erroffset;

 	if (!cs)
 		flags |= PCRE_CASELESS;
 	if (!cap)
 		flags |= PCRE_NO_AUTO_CAPTURE;

 	regex->reg = pcre_compile(str, flags, &error, &erroffset, NULL);
 	if (!regex->reg) {
 		memprintf(err, "regex '%s' is invalid (error=%s, erroffset=%d)", str, error, erroffset);
 		return 0;
 	}

 #ifdef USE_PCRE_JIT
 	regex->extra = pcre_study(regex->reg, PCRE_STUDY_JIT_COMPILE, &error);
 	if (!regex->extra && error != NULL) {
 		pcre_free(regex->reg);
 		memprintf(err, "failed to compile regex '%s' (error=%s)", str, error);
 		return 0;
 	}
 #else
 	regex->extra = NULL;
 #endif
 #else
 	int flags = REG_EXTENDED;

 	if (!cs)
 		flags |= REG_ICASE;
 	if (!cap)
 		flags |= REG_NOSUB;

 	if (regcomp(&regex->regex, str, flags) != 0) {
 		memprintf(err, "regex '%s' is invalid", str);
 		return 0;
 	}
 #endif
 	return 1;
 }

 /*
  * Local variables:
  *  c-indent-level: 8
  *  c-basic-offset: 8
  * End:
  */
	/*
	* Regex and string management functions.
	*
	* Copyright 2000-2010 Willy Tarreau <w@1wt.eu>
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version
	* 2 of the License, or (at your option) any later version.
	*
	*/

	#include <ctype.h>
	#include <stdlib.h>
	#include <string.h>

	#include <common/config.h>
	#include <common/defaults.h>
	#include <common/regex.h>
	#include <common/standard.h>
	#include <proto/log.h>

	/* regex trash buffer used by various regex tests */
	regmatch_t pmatch[MAX_MATCH]; /* rm_so, rm_eo for regular expressions */

	int exp_replace(char dst, unsigned int dst_size, char src, const char str, const regmatch_t matches)
	{
	char *old_dst = dst;
	char* dst_end = dst + dst_size;

	while (*str) {
	if (*str == '\\') {
	str++;
	if (!*str)
	return -1;

	if (isdigit((unsigned char)*str)) {
	int len, num;

	num = *str - '0';
	str++;

	if (matches[num].rm_eo > -1 && matches[num].rm_so > -1) {
	len = matches[num].rm_eo - matches[num].rm_so;

	if (dst + len >= dst_end)
	return -1;

	memcpy(dst, src + matches[num].rm_so, len);
	dst += len;
	}

	} else if (*str == 'x') {
	unsigned char hex1, hex2;
	str++;

	if (!*str)
	return -1;

	hex1 = toupper(*str++) - '0';

	if (!*str)
	return -1;

	hex2 = toupper(*str++) - '0';

	if (hex1 > 9) hex1 -= 'A' - '9' - 1;
	if (hex2 > 9) hex2 -= 'A' - '9' - 1;

	if (dst >= dst_end)
	return -1;

	*dst++ = (hex1<<4) + hex2;
	} else {
	if (dst >= dst_end)
	return -1;

	dst++ = str++;
	}
	} else {
	if (dst >= dst_end)
	return -1;

	dst++ = str++;
	}
	}
	if (dst >= dst_end)
	return -1;

	*dst = '\0';
	return dst - old_dst;
	}

	/* returns NULL if the replacement string <str> is valid, or the pointer to the first error */
	const char check_replace_string(const char str)
	{
	const char *err = NULL;
	while (*str) {
	if (*str == '\\') {
	err = str; /* in case of a backslash, we return the pointer to it */
	str++;
	if (!*str)
	return err;
	else if (isdigit((unsigned char)*str))
	err = NULL;
	else if (*str == 'x') {
	str++;
	if (!ishex(*str))
	return err;
	str++;
	if (!ishex(*str))
	return err;
	err = NULL;
	}
	else {
	Warning("'\\%c' : deprecated use of a backslash before something not '\\','x' or a digit.\n", *str);
	err = NULL;
	}
	}
	str++;
	}
	return err;
	}


	/* returns the pointer to an error in the replacement string, or NULL if OK */
	const char chain_regex(struct hdr_exp head, struct my_regex preg,
	int action, const char replace, void cond)
	{
	struct hdr_exp *exp;

	if (replace != NULL) {
	const char *err;
	err = check_replace_string(replace);
	if (err)
	return err;
	}

	while (*head != NULL)
	head = &(*head)->next;

	exp = calloc(1, sizeof(struct hdr_exp));

	exp->preg = preg;
	exp->replace = replace;
	exp->action = action;
	exp->cond = cond;
	*head = exp;

	return NULL;
	}

	/* This function apply regex. It take const null terminated char as input.
	* If the function doesn't match, it returns false, else it returns true.
	* When it is compiled with JIT, this function execute strlen on the subject.
	*/
	int regex_exec_match(const struct my_regex preg, const char subject,
	size_t nmatch, regmatch_t pmatch[]) {
	#if defined(USE_PCRE) \|\| defined(USE_PCRE_JIT)
	int ret;
	int matches[MAX_MATCH * 3];
	int enmatch;
	int i;

	/* Silently limit the number of allowed matches. max
	* match i the maximum value for match, in fact this
	* limit is not applyied.
	*/
	enmatch = nmatch;
	if (enmatch > MAX_MATCH)
	enmatch = MAX_MATCH;

	/* The value returned by pcre_exec() is one more than the highest numbered
	* pair that has been set. For example, if two substrings have been captured,
	* the returned value is 3. If there are no capturing subpatterns, the return
	* value from a successful match is 1, indicating that just the first pair of
	* offsets has been set.
	*
	* It seems that this function returns 0 if it detect more matches than avalaible
	* space in the matches array.
	*/
	ret = pcre_exec(preg->reg, preg->extra, subject, strlen(subject), 0, 0, matches, enmatch * 3);
	if (ret < 0)
	return 0;

	if (ret == 0)
	ret = enmatch;

	for (i=0; i<nmatch; i++) {
	/* Copy offset. */
	if (i < ret) {
	pmatch[i].rm_so = matches[(i*2)];
	pmatch[i].rm_eo = matches[(i*2)+1];
	continue;
	}
	/* Set the unmatvh flag (-1). */
	pmatch[i].rm_so = -1;
	pmatch[i].rm_eo = -1;
	}
	return 1;
	#else
	int match;
	match = regexec(&preg->regex, subject, nmatch, pmatch, 0);
	if (match == REG_NOMATCH)
	return 0;
	return 1;
	#endif
	}

	/* This function apply regex. It take a "char *" ans length as input. The
	* <subject> can be modified during the processing. If the function doesn't
	* match, it returns false, else it returns true.
	* When it is compiled with standard POSIX regex or PCRE, this function add
	* a temporary null chracters at the end of the <subject>. The <subject> must
	* have a real length of <length> + 1.
	*/
	int regex_exec_match2(const struct my_regex preg, char subject, int length,
	size_t nmatch, regmatch_t pmatch[]) {
	#if defined(USE_PCRE) \|\| defined(USE_PCRE_JIT)
	int ret;
	int matches[MAX_MATCH * 3];
	int enmatch;
	int i;

	/* Silently limit the number of allowed matches. max
	* match i the maximum value for match, in fact this
	* limit is not applyied.
	*/
	enmatch = nmatch;
	if (enmatch > MAX_MATCH)
	enmatch = MAX_MATCH;

	/* The value returned by pcre_exec() is one more than the highest numbered
	* pair that has been set. For example, if two substrings have been captured,
	* the returned value is 3. If there are no capturing subpatterns, the return
	* value from a successful match is 1, indicating that just the first pair of
	* offsets has been set.
	*
	* It seems that this function returns 0 if it detect more matches than avalaible
	* space in the matches array.
	*/
	ret = pcre_exec(preg->reg, preg->extra, subject, length, 0, 0, matches, enmatch * 3);
	if (ret < 0)
	return 0;

	if (ret == 0)
	ret = enmatch;

	for (i=0; i<nmatch; i++) {
	/* Copy offset. */
	if (i < ret) {
	pmatch[i].rm_so = matches[(i*2)];
	pmatch[i].rm_eo = matches[(i*2)+1];
	continue;
	}
	/* Set the unmatvh flag (-1). */
	pmatch[i].rm_so = -1;
	pmatch[i].rm_eo = -1;
	}
	return 1;
	#else
	char old_char = subject[length];
	int match;
	subject[length] = 0;
	match = regexec(&preg->regex, subject, nmatch, pmatch, 0);
	subject[length] = old_char;
	if (match == REG_NOMATCH)
	return 0;
	return 1;
	#endif
	}

	int regex_comp(const char str, struct my_regex regex, int cs, int cap, char **err)
	{
	#if defined(USE_PCRE) \|\| defined(USE_PCRE_JIT)
	int flags = 0;
	const char *error;
	int erroffset;

	if (!cs)
	flags \|= PCRE_CASELESS;
	if (!cap)
	flags \|= PCRE_NO_AUTO_CAPTURE;

	regex->reg = pcre_compile(str, flags, &error, &erroffset, NULL);
	if (!regex->reg) {
	memprintf(err, "regex '%s' is invalid (error=%s, erroffset=%d)", str, error, erroffset);
	return 0;
	}

	#ifdef USE_PCRE_JIT
	regex->extra = pcre_study(regex->reg, PCRE_STUDY_JIT_COMPILE, &error);
	if (!regex->extra && error != NULL) {
	pcre_free(regex->reg);
	memprintf(err, "failed to compile regex '%s' (error=%s)", str, error);
	return 0;
	}
	#else
	regex->extra = NULL;
	#endif
	#else
	int flags = REG_EXTENDED;

	if (!cs)
	flags \|= REG_ICASE;
	if (!cap)
	flags \|= REG_NOSUB;

	if (regcomp(&regex->regex, str, flags) != 0) {
	memprintf(err, "regex '%s' is invalid", str);
	return 0;
	}
	#endif
	return 1;
	}

	/*
	* Local variables:
	* c-indent-level: 8
	* c-basic-offset: 8
	* End:
	*/