/* v3_utl.c */

 /* Written by Dr Stephen N Henson (shenson@bigfoot.com) for the OpenSSL

  * project.

  */

 /* ====================================================================

  * Copyright (c) 1999-2003 The OpenSSL Project.  All rights reserved.

  *

  * Redistribution and use in source and binary forms, with or without

  * modification, are permitted provided that the following conditions

  * are met:

  *

  * 1. Redistributions of source code must retain the above copyright

  *    notice, this list of conditions and the following disclaimer. 

  *

  * 2. 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.

  *

  * 3. All advertising materials mentioning features or use of this

  *    software must display the following acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit. (http://www.OpenSSL.org/)"

  *

  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to

  *    endorse or promote products derived from this software without

  *    prior written permission. For written permission, please contact

  *    licensing@OpenSSL.org.

  *

  * 5. Products derived from this software may not be called "OpenSSL"

  *    nor may "OpenSSL" appear in their names without prior written

  *    permission of the OpenSSL Project.

  *

  * 6. Redistributions of any form whatsoever must retain the following

  *    acknowledgment:

  *    "This product includes software developed by the OpenSSL Project

  *    for use in the OpenSSL Toolkit (http://www.OpenSSL.org/)"

  *

  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY

  * EXPRESSED 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 THE OpenSSL PROJECT OR

  * ITS 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.

  * ====================================================================

  *

  * This product includes cryptographic software written by Eric Young

  * (eay@cryptsoft.com).  This product includes software written by Tim

  * Hudson (tjh@cryptsoft.com).

  *

  */

  /*

  © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

  */

 /* X509 v3 extension utilities */

 #include <stdio.h>

 #include <ctype.h>

 #include "cryptlib.h"

 #include <openssl/conf.h>

 #include <openssl/x509v3.h>

 #include <openssl/bn.h>

 #if (defined(SYMBIAN) && (defined(__WINSCW__) || defined(__WINS__)))

 #include "libcrypto_wsd_macros.h"

 #include "libcrypto_wsd.h"

 #endif

 static char *strip_spaces(char *name);

 static int sk_strcmp(const char * const *a, const char * const *b);

 static STACK *get_email(X509_NAME *name, GENERAL_NAMES *gens);

 static void str_free(void *str);

 static int append_ia5(STACK **sk, ASN1_IA5STRING *email);

 static int ipv4_from_asc(unsigned char *v4, const char *in);

 static int ipv6_from_asc(unsigned char *v6, const char *in);

 static int ipv6_cb(const char *elem, int len, void *usr);

 static int ipv6_hex(unsigned char *out, const char *in, int inlen);

 /* Add a CONF_VALUE name value pair to stack */

 EXPORT_C int X509V3_add_value(const char *name, const char *value,

 						STACK_OF(CONF_VALUE) **extlist)

 {

 	CONF_VALUE *vtmp = NULL;

 	char *tname = NULL, *tvalue = NULL;

 	if(name && !(tname = BUF_strdup(name))) goto err;

 	if(value && !(tvalue = BUF_strdup(value))) goto err;;

 	if(!(vtmp = (CONF_VALUE *)OPENSSL_malloc(sizeof(CONF_VALUE)))) goto err;

 	if(!*extlist && !(*extlist = sk_CONF_VALUE_new_null())) goto err;

 	vtmp->section = NULL;

 	vtmp->name = tname;

 	vtmp->value = tvalue;

 	if(!sk_CONF_VALUE_push(*extlist, vtmp)) goto err;

 	return 1;

 	err:

 	X509V3err(X509V3_F_X509V3_ADD_VALUE,ERR_R_MALLOC_FAILURE);

 	if(vtmp) OPENSSL_free(vtmp);

 	if(tname) OPENSSL_free(tname);

 	if(tvalue) OPENSSL_free(tvalue);

 	return 0;

 }

 EXPORT_C int X509V3_add_value_uchar(const char *name, const unsigned char *value,

 			   STACK_OF(CONF_VALUE) **extlist)

     {

     return X509V3_add_value(name,(const char *)value,extlist);

     }

 /* Free function for STACK_OF(CONF_VALUE) */

 EXPORT_C void X509V3_conf_free(CONF_VALUE *conf)

 {

 	if(!conf) return;

 	if(conf->name) OPENSSL_free(conf->name);

 	if(conf->value) OPENSSL_free(conf->value);

 	if(conf->section) OPENSSL_free(conf->section);

 	OPENSSL_free(conf);

 }

 EXPORT_C int X509V3_add_value_bool(const char *name, int asn1_bool,

 						STACK_OF(CONF_VALUE) **extlist)

 {

 	if(asn1_bool) return X509V3_add_value(name, "TRUE", extlist);

 	return X509V3_add_value(name, "FALSE", extlist);

 }

 EXPORT_C int X509V3_add_value_bool_nf(char *name, int asn1_bool,

 						STACK_OF(CONF_VALUE) **extlist)

 {

 	if(asn1_bool) return X509V3_add_value(name, "TRUE", extlist);

 	return 1;

 }

 EXPORT_C char *i2s_ASN1_ENUMERATED(X509V3_EXT_METHOD *method, ASN1_ENUMERATED *a)

 {

 	BIGNUM *bntmp = NULL;

 	char *strtmp = NULL;

 	if(!a) return NULL;

 	if(!(bntmp = ASN1_ENUMERATED_to_BN(a, NULL)) ||

 	    !(strtmp = BN_bn2dec(bntmp)) )

 		X509V3err(X509V3_F_I2S_ASN1_ENUMERATED,ERR_R_MALLOC_FAILURE);

 	BN_free(bntmp);

 	return strtmp;

 }

 EXPORT_C char *i2s_ASN1_INTEGER(X509V3_EXT_METHOD *method, ASN1_INTEGER *a)

 {

 	BIGNUM *bntmp = NULL;

 	char *strtmp = NULL;

 	if(!a) return NULL;

 	if(!(bntmp = ASN1_INTEGER_to_BN(a, NULL)) ||

 	    !(strtmp = BN_bn2dec(bntmp)) )

 		X509V3err(X509V3_F_I2S_ASN1_INTEGER,ERR_R_MALLOC_FAILURE);

 	BN_free(bntmp);

 	return strtmp;

 }

 EXPORT_C ASN1_INTEGER *s2i_ASN1_INTEGER(X509V3_EXT_METHOD *method, char *value)

 {

 	BIGNUM *bn = NULL;

 	ASN1_INTEGER *aint;

 	int isneg, ishex;

 	int ret;

 	if (!value) {

 		X509V3err(X509V3_F_S2I_ASN1_INTEGER,X509V3_R_INVALID_NULL_VALUE);

 		return 0;

 	}

 	bn = BN_new();

 	if (value[0] == '-') {

 		value++;

 		isneg = 1;

 	} else isneg = 0;

 	if (value[0] == '0' && ((value[1] == 'x') || (value[1] == 'X'))) {

 		value += 2;

 		ishex = 1;

 	} else ishex = 0;

 	if (ishex) ret = BN_hex2bn(&bn, value);

 	else ret = BN_dec2bn(&bn, value);

 	if (!ret || value[ret]) {

 		BN_free(bn);

 		X509V3err(X509V3_F_S2I_ASN1_INTEGER,X509V3_R_BN_DEC2BN_ERROR);

 		return 0;

 	}

 	if (isneg && BN_is_zero(bn)) isneg = 0;

 	aint = BN_to_ASN1_INTEGER(bn, NULL);

 	BN_free(bn);

 	if (!aint) {

 		X509V3err(X509V3_F_S2I_ASN1_INTEGER,X509V3_R_BN_TO_ASN1_INTEGER_ERROR);

 		return 0;

 	}

 	if (isneg) aint->type |= V_ASN1_NEG;

 	return aint;

 }

 EXPORT_C int X509V3_add_value_int(const char *name, ASN1_INTEGER *aint,

 	     STACK_OF(CONF_VALUE) **extlist)

 {

 	char *strtmp;

 	int ret;

 	if(!aint) return 1;

 	if(!(strtmp = i2s_ASN1_INTEGER(NULL, aint))) return 0;

 	ret = X509V3_add_value(name, strtmp, extlist);

 	OPENSSL_free(strtmp);

 	return ret;

 }

 EXPORT_C int X509V3_get_value_bool(CONF_VALUE *value, int *asn1_bool)

 {

 	char *btmp;

 	if(!(btmp = value->value)) goto err;

 	if(!strcmp(btmp, "TRUE") || !strcmp(btmp, "true")

 		 || !strcmp(btmp, "Y") || !strcmp(btmp, "y")

 		|| !strcmp(btmp, "YES") || !strcmp(btmp, "yes")) {

 		*asn1_bool = 0xff;

 		return 1;

 	} else if(!strcmp(btmp, "FALSE") || !strcmp(btmp, "false")

 		 || !strcmp(btmp, "N") || !strcmp(btmp, "n")

 		|| !strcmp(btmp, "NO") || !strcmp(btmp, "no")) {

 		*asn1_bool = 0;

 		return 1;

 	}

 	err:

 	X509V3err(X509V3_F_X509V3_GET_VALUE_BOOL,X509V3_R_INVALID_BOOLEAN_STRING);

 	X509V3_conf_err(value);

 	return 0;

 }

 EXPORT_C int X509V3_get_value_int(CONF_VALUE *value, ASN1_INTEGER **aint)

 {

 	ASN1_INTEGER *itmp;

 	if(!(itmp = s2i_ASN1_INTEGER(NULL, value->value))) {

 		X509V3_conf_err(value);

 		return 0;

 	}

 	*aint = itmp;

 	return 1;

 }

 #define HDR_NAME	1

 #define HDR_VALUE	2

 /*#define DEBUG*/

 EXPORT_C STACK_OF(CONF_VALUE) *X509V3_parse_list(const char *line)

 {

 	char *p, *q, c;

 	char *ntmp, *vtmp;

 	STACK_OF(CONF_VALUE) *values = NULL;

 	char *linebuf;

 	int state;

 	/* We are going to modify the line so copy it first */

 	linebuf = BUF_strdup(line);

 	state = HDR_NAME;

 	ntmp = NULL;

 	/* Go through all characters */

 	for(p = linebuf, q = linebuf; (c = *p) && (c!='\r') && (c!='\n'); p++) {

 		switch(state) {

 			case HDR_NAME:

 			if(c == ':') {

 				state = HDR_VALUE;

 				*p = 0;

 				ntmp = strip_spaces(q);

 				if(!ntmp) {

 					X509V3err(X509V3_F_X509V3_PARSE_LIST, X509V3_R_INVALID_NULL_NAME);

 					goto err;

 				}

 				q = p + 1;

 			} else if(c == ',') {

 				*p = 0;

 				ntmp = strip_spaces(q);

 				q = p + 1;

 #if 0

 				printf("%s\n", ntmp);

 #endif

 				if(!ntmp) {

 					X509V3err(X509V3_F_X509V3_PARSE_LIST, X509V3_R_INVALID_NULL_NAME);

 					goto err;

 				}

 				X509V3_add_value(ntmp, NULL, &values);

 			}

 			break ;

 			case HDR_VALUE:

 			if(c == ',') {

 				state = HDR_NAME;

 				*p = 0;

 				vtmp = strip_spaces(q);

 #if 0

 				printf("%s\n", ntmp);

 #endif

 				if(!vtmp) {

 					X509V3err(X509V3_F_X509V3_PARSE_LIST, X509V3_R_INVALID_NULL_VALUE);

 					goto err;

 				}

 				X509V3_add_value(ntmp, vtmp, &values);

 				ntmp = NULL;

 				q = p + 1;

 			}

 		}

 	}

 	if(state == HDR_VALUE) {

 		vtmp = strip_spaces(q);

 #if 0

 		printf("%s=%s\n", ntmp, vtmp);

 #endif

 		if(!vtmp) {

 			X509V3err(X509V3_F_X509V3_PARSE_LIST, X509V3_R_INVALID_NULL_VALUE);

 			goto err;

 		}

 		X509V3_add_value(ntmp, vtmp, &values);

 	} else {

 		ntmp = strip_spaces(q);

 #if 0

 		printf("%s\n", ntmp);

 #endif

 		if(!ntmp) {

 			X509V3err(X509V3_F_X509V3_PARSE_LIST, X509V3_R_INVALID_NULL_NAME);

 			goto err;

 		}

 		X509V3_add_value(ntmp, NULL, &values);

 	}

 OPENSSL_free(linebuf);

 return values;

 err:

 OPENSSL_free(linebuf);

 sk_CONF_VALUE_pop_free(values, X509V3_conf_free);

 return NULL;

 }

 /* Delete leading and trailing spaces from a string */

 static char *strip_spaces(char *name)

 {

 	char *p, *q;

 	/* Skip over leading spaces */

 	p = name;

 	while(*p && isspace((unsigned char)*p)) p++;

 	if(!*p) return NULL;

 	q = p + strlen(p) - 1;

 	while((q != p) && isspace((unsigned char)*q)) q--;

 	if(p != q) q[1] = 0;

 	if(!*p) return NULL;

 	return p;

 }

 /* hex string utilities */

 /* Given a buffer of length 'len' return a OPENSSL_malloc'ed string with its

  * hex representation

  * @@@ (Contents of buffer are always kept in ASCII, also on EBCDIC machines)

  */

 EXPORT_C char *hex_to_string(unsigned char *buffer, long len)

 {

 	char *tmp, *q;

 	unsigned char *p;

 	int i;

 #ifndef EMULATOR	

 	static char hexdig[] = "0123456789ABCDEF";

 #else

     static const char hexdig[] = "0123456789ABCDEF";

 #endif	

 	if(!buffer || !len) return NULL;

 	if(!(tmp = OPENSSL_malloc(len * 3 + 1))) {

 		X509V3err(X509V3_F_HEX_TO_STRING,ERR_R_MALLOC_FAILURE);

 		return NULL;

 	}

 	q = tmp;

 	for(i = 0, p = buffer; i < len; i++,p++) {

 		*q++ = hexdig[(*p >> 4) & 0xf];

 		*q++ = hexdig[*p & 0xf];

 		*q++ = ':';

 	}

 	q[-1] = 0;

 #ifdef CHARSET_EBCDIC

 	ebcdic2ascii(tmp, tmp, q - tmp - 1);

 #endif

 	return tmp;

 }

 /* Give a string of hex digits convert to

  * a buffer

  */

 EXPORT_C unsigned char *string_to_hex(char *str, long *len)

 {

 	unsigned char *hexbuf, *q;

 	unsigned char ch, cl, *p;

 	if(!str) {

 		X509V3err(X509V3_F_STRING_TO_HEX,X509V3_R_INVALID_NULL_ARGUMENT);

 		return NULL;

 	}

 	if(!(hexbuf = OPENSSL_malloc(strlen(str) >> 1))) goto err;

 	for(p = (unsigned char *)str, q = hexbuf; *p;) {

 		ch = *p++;

 #ifdef CHARSET_EBCDIC

 		ch = os_toebcdic[ch];

 #endif

 		if(ch == ':') continue;

 		cl = *p++;

 #ifdef CHARSET_EBCDIC

 		cl = os_toebcdic[cl];

 #endif

 		if(!cl) {

 			X509V3err(X509V3_F_STRING_TO_HEX,X509V3_R_ODD_NUMBER_OF_DIGITS);

 			OPENSSL_free(hexbuf);

 			return NULL;

 		}

 		if(isupper(ch)) ch = tolower(ch);

 		if(isupper(cl)) cl = tolower(cl);

 		if((ch >= '0') && (ch <= '9')) ch -= '0';

 		else if ((ch >= 'a') && (ch <= 'f')) ch -= 'a' - 10;

 		else goto badhex;

 		if((cl >= '0') && (cl <= '9')) cl -= '0';

 		else if ((cl >= 'a') && (cl <= 'f')) cl -= 'a' - 10;

 		else goto badhex;

 		*q++ = (ch << 4) | cl;

 	}

 	if(len) *len = q - hexbuf;

 	return hexbuf;

 	err:

 	if(hexbuf) OPENSSL_free(hexbuf);

 	X509V3err(X509V3_F_STRING_TO_HEX,ERR_R_MALLOC_FAILURE);

 	return NULL;

 	badhex:

 	OPENSSL_free(hexbuf);

 	X509V3err(X509V3_F_STRING_TO_HEX,X509V3_R_ILLEGAL_HEX_DIGIT);

 	return NULL;

 }

 /* V2I name comparison function: returns zero if 'name' matches

  * cmp or cmp.*

  */

 EXPORT_C int name_cmp(const char *name, const char *cmp)

 {

 	int len, ret;

 	char c;

 	len = strlen(cmp);

 	if((ret = strncmp(name, cmp, len))) return ret;

 	c = name[len];

 	if(!c || (c=='.')) return 0;

 	return 1;

 }

 static int sk_strcmp(const char * const *a, const char * const *b)

 {

 	return strcmp(*a, *b);

 }

 EXPORT_C STACK *X509_get1_email(X509 *x)

 {

 	GENERAL_NAMES *gens;

 	STACK *ret;

 	gens = X509_get_ext_d2i(x, NID_subject_alt_name, NULL, NULL);

 	ret = get_email(X509_get_subject_name(x), gens);

 	sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);

 	return ret;

 }

 EXPORT_C STACK *X509_REQ_get1_email(X509_REQ *x)

 {

 	GENERAL_NAMES *gens;

 	STACK_OF(X509_EXTENSION) *exts;

 	STACK *ret;

 	exts = X509_REQ_get_extensions(x);

 	gens = X509V3_get_d2i(exts, NID_subject_alt_name, NULL, NULL);

 	ret = get_email(X509_REQ_get_subject_name(x), gens);

 	sk_GENERAL_NAME_pop_free(gens, GENERAL_NAME_free);

 	sk_X509_EXTENSION_pop_free(exts, X509_EXTENSION_free);

 	return ret;

 }

 static STACK *get_email(X509_NAME *name, GENERAL_NAMES *gens)

 {

 	STACK *ret = NULL;

 	X509_NAME_ENTRY *ne;

 	ASN1_IA5STRING *email;

 	GENERAL_NAME *gen;

 	int i;

 	/* Now add any email address(es) to STACK */

 	i = -1;

 	/* First supplied X509_NAME */

 	while((i = X509_NAME_get_index_by_NID(name,

 					 NID_pkcs9_emailAddress, i)) >= 0) {

 		ne = X509_NAME_get_entry(name, i);

 		email = X509_NAME_ENTRY_get_data(ne);

 		if(!append_ia5(&ret, email)) return NULL;

 	}

 	for(i = 0; i < sk_GENERAL_NAME_num(gens); i++)

 	{

 		gen = sk_GENERAL_NAME_value(gens, i);

 		if(gen->type != GEN_EMAIL) continue;

 		if(!append_ia5(&ret, gen->d.ia5)) return NULL;

 	}

 	return ret;

 }

 static void str_free(void *str)

 {

 	OPENSSL_free(str);

 }

 static int append_ia5(STACK **sk, ASN1_IA5STRING *email)

 {

 	char *emtmp;

 	/* First some sanity checks */

 	if(email->type != V_ASN1_IA5STRING) return 1;

 	if(!email->data || !email->length) return 1;

 	if(!*sk) *sk = sk_new(sk_strcmp);

 	if(!*sk) return 0;

 	/* Don't add duplicates */

 	if(sk_find(*sk, (char *)email->data) != -1) return 1;

 	emtmp = BUF_strdup((char *)email->data);

 	if(!emtmp || !sk_push(*sk, emtmp)) {

 		X509_email_free(*sk);

 		*sk = NULL;

 		return 0;

 	}

 	return 1;

 }

 EXPORT_C void X509_email_free(STACK *sk)

 {

 	sk_pop_free(sk, str_free);

 }

 /* Convert IP addresses both IPv4 and IPv6 into an 

  * OCTET STRING compatible with RFC3280.

  */

 EXPORT_C ASN1_OCTET_STRING *a2i_IPADDRESS(const char *ipasc)

 	{

 	unsigned char ipout[16];

 	ASN1_OCTET_STRING *ret;

 	int iplen;

 	/* If string contains a ':' assume IPv6 */

 	iplen = a2i_ipadd(ipout, ipasc);

 	if (!iplen)

 		return NULL;

 	ret = ASN1_OCTET_STRING_new();

 	if (!ret)

 		return NULL;

 	if (!ASN1_OCTET_STRING_set(ret, ipout, iplen))

 		{

 		ASN1_OCTET_STRING_free(ret);

 		return NULL;

 		}

 	return ret;

 	}

 EXPORT_C ASN1_OCTET_STRING *a2i_IPADDRESS_NC(const char *ipasc)

 	{

 	ASN1_OCTET_STRING *ret = NULL;

 	unsigned char ipout[32];

 	char *iptmp = NULL, *p;

 	int iplen1, iplen2;

 	p = strchr(ipasc,'/');

 	if (!p)

 		return NULL;

 	iptmp = BUF_strdup(ipasc);

 	if (!iptmp)

 		return NULL;

 	p = iptmp + (p - ipasc);

 	*p++ = 0;

 	iplen1 = a2i_ipadd(ipout, iptmp);

 	if (!iplen1)

 		goto err;

 	iplen2 = a2i_ipadd(ipout + iplen1, p);

 	OPENSSL_free(iptmp);

 	iptmp = NULL;

 	if (!iplen2 || (iplen1 != iplen2))

 		goto err;

 	ret = ASN1_OCTET_STRING_new();

 	if (!ret)

 		goto err;

 	if (!ASN1_OCTET_STRING_set(ret, ipout, iplen1 + iplen2))

 		goto err;

 	return ret;

 	err:

 	if (iptmp)

 		OPENSSL_free(iptmp);

 	if (ret)

 		ASN1_OCTET_STRING_free(ret);

 	return NULL;

 	}

 EXPORT_C int a2i_ipadd(unsigned char *ipout, const char *ipasc)

 	{

 	/* If string contains a ':' assume IPv6 */

 	if (strchr(ipasc, ':'))

 		{

 		if (!ipv6_from_asc(ipout, ipasc))

 			return 0;

 		return 16;

 		}

 	else

 		{

 		if (!ipv4_from_asc(ipout, ipasc))

 			return 0;

 		return 4;

 		}

 	}

 static int ipv4_from_asc(unsigned char *v4, const char *in)

 	{

 	int a0, a1, a2, a3;

 	if (sscanf(in, "%d.%d.%d.%d", &a0, &a1, &a2, &a3) != 4)

 		return 0;

 	if ((a0 < 0) || (a0 > 255) || (a1 < 0) || (a1 > 255)

 		|| (a2 < 0) || (a2 > 255) || (a3 < 0) || (a3 > 255))

 		return 0;

 	v4[0] = a0;

 	v4[1] = a1;

 	v4[2] = a2;

 	v4[3] = a3;

 	return 1;

 	}

 typedef struct {

 		/* Temporary store for IPV6 output */

 		unsigned char tmp[16];

 		/* Total number of bytes in tmp */

 		int total;

 		/* The position of a zero (corresponding to '::') */

 		int zero_pos;

 		/* Number of zeroes */

 		int zero_cnt;

 	} IPV6_STAT;

 static int ipv6_from_asc(unsigned char *v6, const char *in)

 	{

 	IPV6_STAT v6stat;

 	v6stat.total = 0;

 	v6stat.zero_pos = -1;

 	v6stat.zero_cnt = 0;

 	/* Treat the IPv6 representation as a list of values

 	 * separated by ':'. The presence of a '::' will parse

  	 * as one, two or three zero length elements.

 	 */

 	if (!CONF_parse_list(in, ':', 0, ipv6_cb, &v6stat))

 		return 0;

 	/* Now for some sanity checks */

 	if (v6stat.zero_pos == -1)

 		{

 		/* If no '::' must have exactly 16 bytes */

 		if (v6stat.total != 16)

 			return 0;

 		}

 	else 

 		{

 		/* If '::' must have less than 16 bytes */

 		if (v6stat.total == 16)

 			return 0;

 		/* More than three zeroes is an error */

 		if (v6stat.zero_cnt > 3)

 			return 0;

 		/* Can only have three zeroes if nothing else present */

 		else if (v6stat.zero_cnt == 3)

 			{

 			if (v6stat.total > 0)

 				return 0;

 			}

 		/* Can only have two zeroes if at start or end */

 		else if (v6stat.zero_cnt == 2)

 			{

 			if ((v6stat.zero_pos != 0)

 				&& (v6stat.zero_pos != v6stat.total))

 				return 0;

 			}

 		else 

 		/* Can only have one zero if *not* start or end */

 			{

 			if ((v6stat.zero_pos == 0)

 				|| (v6stat.zero_pos == v6stat.total))

 				return 0;

 			}

 		}

 	/* Format result */

 	/* Copy initial part */

 	if (v6stat.zero_pos > 0)

 		memcpy(v6, v6stat.tmp, v6stat.zero_pos);

 	/* Zero middle */

 	if (v6stat.total != 16)

 		memset(v6 + v6stat.zero_pos, 0, 16 - v6stat.total);

 	/* Copy final part */

 	if (v6stat.total != v6stat.zero_pos)

 		memcpy(v6 + v6stat.zero_pos + 16 - v6stat.total,

 			v6stat.tmp + v6stat.zero_pos,

 			v6stat.total - v6stat.zero_pos);

 	return 1;

 	}

 static int ipv6_cb(const char *elem, int len, void *usr)

 	{

 	IPV6_STAT *s = usr;

 	/* Error if 16 bytes written */

 	if (s->total == 16)

 		return 0;

 	if (len == 0)

 		{

 		/* Zero length element, corresponds to '::' */

 		if (s->zero_pos == -1)

 			s->zero_pos = s->total;

 		/* If we've already got a :: its an error */

 		else if (s->zero_pos != s->total)

 			return 0;

 		s->zero_cnt++;

 		}

 	else 

 		{

 		/* If more than 4 characters could be final a.b.c.d form */

 		if (len > 4)

 			{

 			/* Need at least 4 bytes left */

 			if (s->total > 12)

 				return 0;

 			/* Must be end of string */

 			if (elem[len])

 				return 0;

 			if (!ipv4_from_asc(s->tmp + s->total, elem))

 				return 0;

 			s->total += 4;

 			}

 		else

 			{

 			if (!ipv6_hex(s->tmp + s->total, elem, len))

 				return 0;

 			s->total += 2;

 			}

 		}

 	return 1;

 	}

 /* Convert a string of up to 4 hex digits into the corresponding

  * IPv6 form.

  */

 static int ipv6_hex(unsigned char *out, const char *in, int inlen)

 	{

 	unsigned char c;

 	unsigned int num = 0;

 	if (inlen > 4)

 		return 0;

 	while(inlen--)

 		{

 		c = *in++;

 		num <<= 4;

 		if ((c >= '0') && (c <= '9'))

 			num |= c - '0';

 		else if ((c >= 'A') && (c <= 'F'))

 			num |= c - 'A' + 10;

 		else if ((c >= 'a') && (c <= 'f'))

 			num |=  c - 'a' + 10;

 		else

 			return 0;

 		}

 	out[0] = num >> 8;

 	out[1] = num & 0xff;

 	return 1;

 	}

 EXPORT_C int X509V3_NAME_from_section(X509_NAME *nm, STACK_OF(CONF_VALUE)*dn_sk,

 						unsigned long chtype)

 	{

 	CONF_VALUE *v;

 	int i, mval;

 	char *p, *type;

 	if (!nm)

 		return 0;

 	for (i = 0; i < sk_CONF_VALUE_num(dn_sk); i++)

 		{

 		v=sk_CONF_VALUE_value(dn_sk,i);

 		type=v->name;

 		/* Skip past any leading X. X: X, etc to allow for

 		 * multiple instances 

 		 */

 		for(p = type; *p ; p++) 

 #ifndef CHARSET_EBCDIC

 			if ((*p == ':') || (*p == ',') || (*p == '.'))

 #else

 			if ((*p == os_toascii[':']) || (*p == os_toascii[',']) || (*p == os_toascii['.']))

 #endif

 				{

 				p++;

 				if(*p) type = p;

 				break;

 				}

 #ifndef CHARSET_EBCDIC

 		if (*type == '+')

 #else

 		if (*type == os_toascii['+'])

 #endif

 			{

 			mval = -1;

 			type++;

 			}

 		else

 			mval = 0;

 		if (!X509_NAME_add_entry_by_txt(nm,type, chtype,

 				(unsigned char *) v->value,-1,-1,mval))

 					return 0;

 		}

 	return 1;

 	}