crypto/srp/srp_vfy.c - chromiumos/third_party/openssl - Git at Google

 /* crypto/srp/srp_vfy.c */
 /* Written by Christophe Renou (christophe.renou@edelweb.fr) with
  * the precious help of Peter Sylvester (peter.sylvester@edelweb.fr)
  * for the EdelKey project and contributed to the OpenSSL project 2004.
  */
 /* ====================================================================
  * Copyright (c) 2004 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).
  *
  */
 #ifndef OPENSSL_NO_SRP
 #include "cryptlib.h"
 #include "srp_lcl.h"
 #include <openssl/srp.h>
 #include <openssl/evp.h>
 #include <openssl/buffer.h>
 #include <openssl/rand.h>
 #include <openssl/txt_db.h>

 #define SRP_RANDOM_SALT_LEN 20
 #define MAX_LEN 2500

 static char b64table[] =
   "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./";

 /* the following two conversion routines have been inspired by code from Stanford */

 /*
  * Convert a base64 string into raw byte array representation.
  */
 static int t_fromb64(unsigned char *a, const char *src)
 	{
 	char *loc;
 	int i, j;
 	int size;

 	while(*src && (*src == ' ' || *src == '\t' || *src == '\n'))
 		++src;
 	size = strlen(src);
 	i = 0;
 	while(i < size)
 		{
 		loc = strchr(b64table, src[i]);
 		if(loc == (char *) 0) break;
 		else a[i] = loc - b64table;
 		++i;
 		}
 	size = i;
 	i = size - 1;
 	j = size;
 	while(1)
 		{
 		a[j] = a[i];
 		if(--i < 0) break;
 		a[j] |= (a[i] & 3) << 6;
 		--j;
 		a[j] = (unsigned char) ((a[i] & 0x3c) >> 2);
 		if(--i < 0) break;
 		a[j] |= (a[i] & 0xf) << 4;
 		--j;
 		a[j] = (unsigned char) ((a[i] & 0x30) >> 4);
 		if(--i < 0) break;
 		a[j] |= (a[i] << 2);

 		a[--j] = 0;
 		if(--i < 0) break;
 		}
 	while(a[j] == 0 && j <= size) ++j;
 	i = 0;
 	while (j <= size) a[i++] = a[j++];
 	return i;
 	}


 /*
  * Convert a raw byte string into a null-terminated base64 ASCII string.
  */
 static char *t_tob64(char *dst, const unsigned char *src, int size)
 	{
 	int c, pos = size % 3;
 	unsigned char b0 = 0, b1 = 0, b2 = 0, notleading = 0;
 	char *olddst = dst;

 	switch(pos)
 		{
 	case 1:
 		b2 = src[0];
 		break;
 	case 2:
 		b1 = src[0];
 		b2 = src[1];
 		break;
 		}

 	while(1)
 		{
 		c = (b0 & 0xfc) >> 2;
 		if(notleading || c != 0)
 			{
 			*dst++ = b64table[c];
 			notleading = 1;
 			}
 		c = ((b0 & 3) << 4) | ((b1 & 0xf0) >> 4);
 		if(notleading || c != 0)
 			{
 			*dst++ = b64table[c];
 			notleading = 1;
 			}
 		c = ((b1 & 0xf) << 2) | ((b2 & 0xc0) >> 6);
 		if(notleading || c != 0)
 			{
 			*dst++ = b64table[c];
 			notleading = 1;
 			}
 		c = b2 & 0x3f;
 		if(notleading || c != 0)
 			{
 			*dst++ = b64table[c];
 			notleading = 1;
 			}
 		if(pos >= size) break;
 		else
 			{
 			b0 = src[pos++];
 			b1 = src[pos++];
 			b2 = src[pos++];
 			}
 		}

 	*dst++ = '\0';
 	return olddst;
 	}

 static void SRP_user_pwd_free(SRP_user_pwd *user_pwd)
 	{
 	if (user_pwd == NULL)
 		return;
 	BN_free(user_pwd->s);
 	BN_clear_free(user_pwd->v);
 	OPENSSL_free(user_pwd->id);
 	OPENSSL_free(user_pwd->info);
 	OPENSSL_free(user_pwd);
 	}

 static SRP_user_pwd *SRP_user_pwd_new()
 	{
 	SRP_user_pwd *ret = OPENSSL_malloc(sizeof(SRP_user_pwd));
 	if (ret == NULL)
 		return NULL;
 	ret->N = NULL;
 	ret->g = NULL;
 	ret->s = NULL;
 	ret->v = NULL;
 	ret->id = NULL ;
 	ret->info = NULL;
 	return ret;
 	}

 static void SRP_user_pwd_set_gN(SRP_user_pwd *vinfo, const BIGNUM *g,
 				const BIGNUM *N)
 	{
 	vinfo->N = N;
 	vinfo->g = g;
 	}

 static int SRP_user_pwd_set_ids(SRP_user_pwd *vinfo, const char *id,
 				const char *info)
 	{
 	if (id != NULL && NULL == (vinfo->id = BUF_strdup(id)))
 		return 0;
 	return (info == NULL || NULL != (vinfo->info = BUF_strdup(info))) ;
 	}

 static int SRP_user_pwd_set_sv(SRP_user_pwd *vinfo, const char *s,
 			       const char *v)
 	{
 	unsigned char tmp[MAX_LEN];
 	int len;

 	if (strlen(s) > MAX_LEN || strlen(v) > MAX_LEN)
 		return 0;
 	len = t_fromb64(tmp, v);
 	if (NULL == (vinfo->v = BN_bin2bn(tmp, len, NULL)) )
 		return 0;
 	len = t_fromb64(tmp, s);
 	return ((vinfo->s = BN_bin2bn(tmp, len, NULL)) != NULL) ;
 	}

 static int SRP_user_pwd_set_sv_BN(SRP_user_pwd *vinfo, BIGNUM *s, BIGNUM *v)
 	{
 	vinfo->v = v;
 	vinfo->s = s;
 	return (vinfo->s != NULL && vinfo->v != NULL) ;
 	}

 SRP_VBASE *SRP_VBASE_new(char *seed_key)
 	{
 	SRP_VBASE *vb = (SRP_VBASE *) OPENSSL_malloc(sizeof(SRP_VBASE));

 	if (vb == NULL)
 		return NULL;
 	if (!(vb->users_pwd = sk_SRP_user_pwd_new_null()) ||
 		!(vb->gN_cache = sk_SRP_gN_cache_new_null()))
 		{
 		OPENSSL_free(vb);
 		return NULL;
 		}
 	vb->default_g = NULL;
 	vb->default_N = NULL;
 	vb->seed_key = NULL;
 	if ((seed_key != NULL) &&
 		(vb->seed_key = BUF_strdup(seed_key)) == NULL)
 		{
 		sk_SRP_user_pwd_free(vb->users_pwd);
 		sk_SRP_gN_cache_free(vb->gN_cache);
 		OPENSSL_free(vb);
 		return NULL;
 		}
 	return vb;
 	}


 int SRP_VBASE_free(SRP_VBASE *vb)
 	{
 	sk_SRP_user_pwd_pop_free(vb->users_pwd,SRP_user_pwd_free);
 	sk_SRP_gN_cache_free(vb->gN_cache);
 	OPENSSL_free(vb->seed_key);
 	OPENSSL_free(vb);
 	return 0;
 	}


 static SRP_gN_cache *SRP_gN_new_init(const char *ch)
 	{
 	unsigned char tmp[MAX_LEN];
 	int len;

 	SRP_gN_cache *newgN = (SRP_gN_cache *)OPENSSL_malloc(sizeof(SRP_gN_cache));
 	if (newgN == NULL)
 		return NULL;

 	if ((newgN->b64_bn = BUF_strdup(ch)) == NULL)
 		goto err;

 	len = t_fromb64(tmp, ch);
 	if ((newgN->bn = BN_bin2bn(tmp, len, NULL)))
 		return newgN;

 	OPENSSL_free(newgN->b64_bn);
 err:
 	OPENSSL_free(newgN);
 	return NULL;
 	}


 static void SRP_gN_free(SRP_gN_cache *gN_cache)
 	{
 	if (gN_cache == NULL)
 		return;
 	OPENSSL_free(gN_cache->b64_bn);
 	BN_free(gN_cache->bn);
 	OPENSSL_free(gN_cache);
 	}

 static SRP_gN *SRP_get_gN_by_id(const char *id, STACK_OF(SRP_gN) *gN_tab)
 	{
 	int i;

 	SRP_gN *gN;
 	if (gN_tab != NULL)
 	for(i = 0; i < sk_SRP_gN_num(gN_tab); i++)
 		{
 		gN = sk_SRP_gN_value(gN_tab, i);
 		if (gN && (id == NULL || strcmp(gN->id,id)==0))
 			return gN;
 		}

 	return SRP_get_default_gN(id);
 	}

 static BIGNUM *SRP_gN_place_bn(STACK_OF(SRP_gN_cache) *gN_cache, char *ch)
 	{
 	int i;
 	if (gN_cache == NULL)
 		return NULL;

 	/* search if we have already one... */
 	for(i = 0; i < sk_SRP_gN_cache_num(gN_cache); i++)
 		{
 		SRP_gN_cache *cache = sk_SRP_gN_cache_value(gN_cache, i);
 		if (strcmp(cache->b64_bn,ch)==0)
 			return cache->bn;
 		}
 		{		/* it is the first time that we find it */
 		SRP_gN_cache *newgN = SRP_gN_new_init(ch);
 		if (newgN)
 			{
 			if (sk_SRP_gN_cache_insert(gN_cache,newgN,0)>0)
 				return newgN->bn;
 			SRP_gN_free(newgN);
 			}
 		}
 	return NULL;
 	}

 /* this function parses verifier file. Format is:
  * string(index):base64(N):base64(g):0
  * string(username):base64(v):base64(salt):int(index)
  */


 int SRP_VBASE_init(SRP_VBASE *vb, char *verifier_file)
 	{
 	int error_code ;
 	STACK_OF(SRP_gN) *SRP_gN_tab = sk_SRP_gN_new_null();
 	char *last_index = NULL;
 	int i;
 	char **pp;

 	SRP_gN *gN = NULL;
 	SRP_user_pwd *user_pwd = NULL ;

 	TXT_DB *tmpdb = NULL;
 	BIO *in = BIO_new(BIO_s_file());

 	error_code = SRP_ERR_OPEN_FILE;

 	if (in == NULL || BIO_read_filename(in,verifier_file) <= 0)
 		goto err;

 	error_code = SRP_ERR_VBASE_INCOMPLETE_FILE;

 	if ((tmpdb =TXT_DB_read(in,DB_NUMBER)) == NULL)
 		goto err;

 	error_code = SRP_ERR_MEMORY;


 	if (vb->seed_key)
 		{
 		last_index = SRP_get_default_gN(NULL)->id;
 		}
 	for (i = 0; i < sk_OPENSSL_PSTRING_num(tmpdb->data); i++)
 		{
 		pp = sk_OPENSSL_PSTRING_value(tmpdb->data,i);
 		if (pp[DB_srptype][0] == DB_SRP_INDEX)
 			{
 			/*we add this couple in the internal Stack */

 			if ((gN = (SRP_gN *)OPENSSL_malloc(sizeof(SRP_gN))) == NULL)
  				goto err;

 			if  (!(gN->id = BUF_strdup(pp[DB_srpid]))
 	                ||  !(gN->N = SRP_gN_place_bn(vb->gN_cache,pp[DB_srpverifier]))
 			||  !(gN->g = SRP_gN_place_bn(vb->gN_cache,pp[DB_srpsalt]))
 			||  sk_SRP_gN_insert(SRP_gN_tab,gN,0) == 0)
 				goto err;

 			gN = NULL;

 			if (vb->seed_key != NULL)
 				{
 				last_index = pp[DB_srpid];
 				}
 			}
 		else if (pp[DB_srptype][0] == DB_SRP_VALID)
 			{
 			/* it is a user .... */
 			SRP_gN *lgN;
 			if ((lgN = SRP_get_gN_by_id(pp[DB_srpgN],SRP_gN_tab))!=NULL)
 				{
 				error_code = SRP_ERR_MEMORY;
 				if ((user_pwd = SRP_user_pwd_new()) == NULL)
 					goto err;

 				SRP_user_pwd_set_gN(user_pwd,lgN->g,lgN->N);
 				if (!SRP_user_pwd_set_ids(user_pwd, pp[DB_srpid],pp[DB_srpinfo]))
 					goto err;

 				error_code = SRP_ERR_VBASE_BN_LIB;
 				if (!SRP_user_pwd_set_sv(user_pwd, pp[DB_srpsalt],pp[DB_srpverifier]))
 					goto err;

 				if (sk_SRP_user_pwd_insert(vb->users_pwd, user_pwd, 0) == 0)
 					goto err;
 				user_pwd = NULL; /* abandon responsability */
 				}
 			}
 		}

 	if (last_index != NULL)
 		{
 		/* this means that we want to simulate a default user */

 		if (((gN = SRP_get_gN_by_id(last_index,SRP_gN_tab))==NULL))
 			{
 			error_code = SRP_ERR_VBASE_BN_LIB;
 			goto err;
 			}
 		vb->default_g = gN->g ;
 		vb->default_N = gN->N ;
 		gN = NULL ;
 		}
 	error_code = SRP_NO_ERROR;

  err:
 	/* there may be still some leaks to fix, if this fails, the application terminates most likely */

 	if (gN != NULL)
 		{
 		OPENSSL_free(gN->id);
 		OPENSSL_free(gN);
 		}

 	SRP_user_pwd_free(user_pwd);

 	if (tmpdb) TXT_DB_free(tmpdb);
 	if (in) BIO_free_all(in);

 	sk_SRP_gN_free(SRP_gN_tab);

 	return error_code;

 	}


 SRP_user_pwd *SRP_VBASE_get_by_user(SRP_VBASE *vb, char *username)
 	{
 	int i;
 	SRP_user_pwd *user;
 	unsigned char digv[SHA_DIGEST_LENGTH];
 	unsigned char digs[SHA_DIGEST_LENGTH];
 	EVP_MD_CTX ctxt;

 	if (vb == NULL)
 		return NULL;
 	for(i = 0; i < sk_SRP_user_pwd_num(vb->users_pwd); i++)
 		{
 		user = sk_SRP_user_pwd_value(vb->users_pwd, i);
 		if (strcmp(user->id,username)==0)
 			return user;
 		}
 	if ((vb->seed_key == NULL) ||
 		(vb->default_g == NULL) ||
 		(vb->default_N == NULL))
 		return NULL;

 /* if the user is unknown we set parameters as well if we have a seed_key */

 	if ((user = SRP_user_pwd_new()) == NULL)
 		return NULL;

 	SRP_user_pwd_set_gN(user,vb->default_g,vb->default_N);

 	if (!SRP_user_pwd_set_ids(user,username,NULL))
 		goto err;

 	RAND_pseudo_bytes(digv, SHA_DIGEST_LENGTH);
 	EVP_MD_CTX_init(&ctxt);
 	EVP_DigestInit_ex(&ctxt, EVP_sha1(), NULL);
 	EVP_DigestUpdate(&ctxt, vb->seed_key, strlen(vb->seed_key));
 	EVP_DigestUpdate(&ctxt, username, strlen(username));
 	EVP_DigestFinal_ex(&ctxt, digs, NULL);
 	EVP_MD_CTX_cleanup(&ctxt);
 	if (SRP_user_pwd_set_sv_BN(user, BN_bin2bn(digs,SHA_DIGEST_LENGTH,NULL), BN_bin2bn(digv,SHA_DIGEST_LENGTH, NULL)))
 		return user;

 err:    SRP_user_pwd_free(user);
 	return NULL;
 	}


 /*
    create a verifier (*salt,*verifier,g and N are in base64)
 */
 char *SRP_create_verifier(const char *user, const char *pass, char **salt,
 			  char **verifier, const char *N, const char *g)
 	{
 	int len;
 	char * result=NULL;
 	char *vf;
 	BIGNUM *N_bn = NULL, *g_bn = NULL, *s = NULL, *v = NULL;
 	unsigned char tmp[MAX_LEN];
 	unsigned char tmp2[MAX_LEN];
 	char * defgNid = NULL;

 	if ((user == NULL)||
 		(pass == NULL)||
 		(salt == NULL)||
 		(verifier == NULL))
 		goto err;

 	if (N)
 		{
 		if (!(len = t_fromb64(tmp, N))) goto err;
 		N_bn = BN_bin2bn(tmp, len, NULL);
 		if (!(len = t_fromb64(tmp, g))) goto err;
 		g_bn = BN_bin2bn(tmp, len, NULL);
 		defgNid = "*";
 		}
 	else
 		{
 		SRP_gN * gN = SRP_get_gN_by_id(g, NULL) ;
 		if (gN == NULL)
 			goto err;
 		N_bn = gN->N;
 		g_bn = gN->g;
 		defgNid = gN->id;
 		}

 	if (*salt == NULL)
 		{
 		RAND_pseudo_bytes(tmp2, SRP_RANDOM_SALT_LEN);

 		s = BN_bin2bn(tmp2, SRP_RANDOM_SALT_LEN, NULL);
 		}
 	else
 		{
 		if (!(len = t_fromb64(tmp2, *salt)))
 			goto err;
 		s = BN_bin2bn(tmp2, len, NULL);
 		}


 	if(!SRP_create_verifier_BN(user, pass, &s, &v, N_bn, g_bn)) goto err;

 	BN_bn2bin(v,tmp);
 	if (((vf = OPENSSL_malloc(BN_num_bytes(v)*2)) == NULL))
 		goto err;
 	t_tob64(vf, tmp, BN_num_bytes(v));

 	*verifier = vf;
 	if (*salt == NULL)
 		{
 		char *tmp_salt;

 		if ((tmp_salt = OPENSSL_malloc(SRP_RANDOM_SALT_LEN * 2)) == NULL)
 			{
 			OPENSSL_free(vf);
 			goto err;
 			}
 		t_tob64(tmp_salt, tmp2, SRP_RANDOM_SALT_LEN);
 		*salt = tmp_salt;
 		}

 	result=defgNid;

 err:
 	if(N)
 		{
 		BN_free(N_bn);
 		BN_free(g_bn);
 		}
 	return result;
 	}

 /*
    create a verifier (*salt,*verifier,g and N are BIGNUMs)
 */
 int SRP_create_verifier_BN(const char *user, const char *pass, BIGNUM **salt, BIGNUM **verifier, BIGNUM *N, BIGNUM *g)
 	{
 	int result=0;
 	BIGNUM *x = NULL;
 	BN_CTX *bn_ctx = BN_CTX_new();
 	unsigned char tmp2[MAX_LEN];

 	if ((user == NULL)||
 		(pass == NULL)||
 		(salt == NULL)||
 		(verifier == NULL)||
 		(N == NULL)||
 		(g == NULL)||
 		(bn_ctx == NULL))
 		goto err;

 	srp_bn_print(N);
 	srp_bn_print(g);

 	if (*salt == NULL)
 		{
 		RAND_pseudo_bytes(tmp2, SRP_RANDOM_SALT_LEN);

 		*salt = BN_bin2bn(tmp2,SRP_RANDOM_SALT_LEN,NULL);
 		}

 	x = SRP_Calc_x(*salt,user,pass);

 	*verifier = BN_new();
 	if(*verifier == NULL) goto err;

 	if (!BN_mod_exp(*verifier,g,x,N,bn_ctx))
 		{
 		BN_clear_free(*verifier);
 		goto err;
 		}

 	srp_bn_print(*verifier);

 	result=1;

 err:

 	BN_clear_free(x);
 	BN_CTX_free(bn_ctx);
 	return result;
 	}


 #endif
	/* crypto/srp/srp_vfy.c */
	/* Written by Christophe Renou (christophe.renou@edelweb.fr) with
	* the precious help of Peter Sylvester (peter.sylvester@edelweb.fr)
	* for the EdelKey project and contributed to the OpenSSL project 2004.
	*/
	/* ====================================================================
	* Copyright (c) 2004 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).
	*
	*/
	#ifndef OPENSSL_NO_SRP
	#include "cryptlib.h"
	#include "srp_lcl.h"
	#include <openssl/srp.h>
	#include <openssl/evp.h>
	#include <openssl/buffer.h>
	#include <openssl/rand.h>
	#include <openssl/txt_db.h>

	#define SRP_RANDOM_SALT_LEN 20
	#define MAX_LEN 2500

	static char b64table[] =
	"0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz./";

	/* the following two conversion routines have been inspired by code from Stanford */

	/*
	* Convert a base64 string into raw byte array representation.
	*/
	static int t_fromb64(unsigned char a, const char src)
	{
	char *loc;
	int i, j;
	int size;

	while(src && (src == ' ' \|\| src == '\t' \|\| src == '\n'))
	++src;
	size = strlen(src);
	i = 0;
	while(i < size)
	{
	loc = strchr(b64table, src[i]);
	if(loc == (char *) 0) break;
	else a[i] = loc - b64table;
	++i;
	}
	size = i;
	i = size - 1;
	j = size;
	while(1)
	{
	a[j] = a[i];
	if(--i < 0) break;
	a[j] \|= (a[i] & 3) << 6;
	--j;
	a[j] = (unsigned char) ((a[i] & 0x3c) >> 2);
	if(--i < 0) break;
	a[j] \|= (a[i] & 0xf) << 4;
	--j;
	a[j] = (unsigned char) ((a[i] & 0x30) >> 4);
	if(--i < 0) break;
	a[j] \|= (a[i] << 2);

	a[--j] = 0;
	if(--i < 0) break;
	}
	while(a[j] == 0 && j <= size) ++j;
	i = 0;
	while (j <= size) a[i++] = a[j++];
	return i;
	}


	/*
	* Convert a raw byte string into a null-terminated base64 ASCII string.
	*/
	static char t_tob64(char dst, const unsigned char *src, int size)
	{
	int c, pos = size % 3;
	unsigned char b0 = 0, b1 = 0, b2 = 0, notleading = 0;
	char *olddst = dst;

	switch(pos)
	{
	case 1:
	b2 = src[0];
	break;
	case 2:
	b1 = src[0];
	b2 = src[1];
	break;
	}

	while(1)
	{
	c = (b0 & 0xfc) >> 2;
	if(notleading \|\| c != 0)
	{
	*dst++ = b64table[c];
	notleading = 1;
	}
	c = ((b0 & 3) << 4) \| ((b1 & 0xf0) >> 4);
	if(notleading \|\| c != 0)
	{
	*dst++ = b64table[c];
	notleading = 1;
	}
	c = ((b1 & 0xf) << 2) \| ((b2 & 0xc0) >> 6);
	if(notleading \|\| c != 0)
	{
	*dst++ = b64table[c];
	notleading = 1;
	}
	c = b2 & 0x3f;
	if(notleading \|\| c != 0)
	{
	*dst++ = b64table[c];
	notleading = 1;
	}
	if(pos >= size) break;
	else
	{
	b0 = src[pos++];
	b1 = src[pos++];
	b2 = src[pos++];
	}
	}

	*dst++ = '\0';
	return olddst;
	}

	static void SRP_user_pwd_free(SRP_user_pwd *user_pwd)
	{
	if (user_pwd == NULL)
	return;
	BN_free(user_pwd->s);
	BN_clear_free(user_pwd->v);
	OPENSSL_free(user_pwd->id);
	OPENSSL_free(user_pwd->info);
	OPENSSL_free(user_pwd);
	}

	static SRP_user_pwd *SRP_user_pwd_new()
	{
	SRP_user_pwd *ret = OPENSSL_malloc(sizeof(SRP_user_pwd));
	if (ret == NULL)
	return NULL;
	ret->N = NULL;
	ret->g = NULL;
	ret->s = NULL;
	ret->v = NULL;
	ret->id = NULL ;
	ret->info = NULL;
	return ret;
	}

	static void SRP_user_pwd_set_gN(SRP_user_pwd vinfo, const BIGNUM g,
	const BIGNUM *N)
	{
	vinfo->N = N;
	vinfo->g = g;
	}

	static int SRP_user_pwd_set_ids(SRP_user_pwd vinfo, const char id,
	const char *info)
	{
	if (id != NULL && NULL == (vinfo->id = BUF_strdup(id)))
	return 0;
	return (info == NULL \|\| NULL != (vinfo->info = BUF_strdup(info))) ;
	}

	static int SRP_user_pwd_set_sv(SRP_user_pwd vinfo, const char s,
	const char *v)
	{
	unsigned char tmp[MAX_LEN];
	int len;

	if (strlen(s) > MAX_LEN \|\| strlen(v) > MAX_LEN)
	return 0;
	len = t_fromb64(tmp, v);
	if (NULL == (vinfo->v = BN_bin2bn(tmp, len, NULL)) )
	return 0;
	len = t_fromb64(tmp, s);
	return ((vinfo->s = BN_bin2bn(tmp, len, NULL)) != NULL) ;
	}

	static int SRP_user_pwd_set_sv_BN(SRP_user_pwd vinfo, BIGNUM s, BIGNUM *v)
	{
	vinfo->v = v;
	vinfo->s = s;
	return (vinfo->s != NULL && vinfo->v != NULL) ;
	}

	SRP_VBASE SRP_VBASE_new(char seed_key)
	{
	SRP_VBASE vb = (SRP_VBASE ) OPENSSL_malloc(sizeof(SRP_VBASE));

	if (vb == NULL)
	return NULL;
	if (!(vb->users_pwd = sk_SRP_user_pwd_new_null()) \|\|
	!(vb->gN_cache = sk_SRP_gN_cache_new_null()))
	{
	OPENSSL_free(vb);
	return NULL;
	}
	vb->default_g = NULL;
	vb->default_N = NULL;
	vb->seed_key = NULL;
	if ((seed_key != NULL) &&
	(vb->seed_key = BUF_strdup(seed_key)) == NULL)
	{
	sk_SRP_user_pwd_free(vb->users_pwd);
	sk_SRP_gN_cache_free(vb->gN_cache);
	OPENSSL_free(vb);
	return NULL;
	}
	return vb;
	}


	int SRP_VBASE_free(SRP_VBASE *vb)
	{
	sk_SRP_user_pwd_pop_free(vb->users_pwd,SRP_user_pwd_free);
	sk_SRP_gN_cache_free(vb->gN_cache);
	OPENSSL_free(vb->seed_key);
	OPENSSL_free(vb);
	return 0;
	}


	static SRP_gN_cache SRP_gN_new_init(const char ch)
	{
	unsigned char tmp[MAX_LEN];
	int len;

	SRP_gN_cache newgN = (SRP_gN_cache )OPENSSL_malloc(sizeof(SRP_gN_cache));
	if (newgN == NULL)
	return NULL;

	if ((newgN->b64_bn = BUF_strdup(ch)) == NULL)
	goto err;

	len = t_fromb64(tmp, ch);
	if ((newgN->bn = BN_bin2bn(tmp, len, NULL)))
	return newgN;

	OPENSSL_free(newgN->b64_bn);
	err:
	OPENSSL_free(newgN);
	return NULL;
	}


	static void SRP_gN_free(SRP_gN_cache *gN_cache)
	{
	if (gN_cache == NULL)
	return;
	OPENSSL_free(gN_cache->b64_bn);
	BN_free(gN_cache->bn);
	OPENSSL_free(gN_cache);
	}

	static SRP_gN SRP_get_gN_by_id(const char id, STACK_OF(SRP_gN) *gN_tab)
	{
	int i;

	SRP_gN *gN;
	if (gN_tab != NULL)
	for(i = 0; i < sk_SRP_gN_num(gN_tab); i++)
	{
	gN = sk_SRP_gN_value(gN_tab, i);
	if (gN && (id == NULL \|\| strcmp(gN->id,id)==0))
	return gN;
	}

	return SRP_get_default_gN(id);
	}

	static BIGNUM SRP_gN_place_bn(STACK_OF(SRP_gN_cache) gN_cache, char *ch)
	{
	int i;
	if (gN_cache == NULL)
	return NULL;

	/* search if we have already one... */
	for(i = 0; i < sk_SRP_gN_cache_num(gN_cache); i++)
	{
	SRP_gN_cache *cache = sk_SRP_gN_cache_value(gN_cache, i);
	if (strcmp(cache->b64_bn,ch)==0)
	return cache->bn;
	}
	{ /* it is the first time that we find it */
	SRP_gN_cache *newgN = SRP_gN_new_init(ch);
	if (newgN)
	{
	if (sk_SRP_gN_cache_insert(gN_cache,newgN,0)>0)
	return newgN->bn;
	SRP_gN_free(newgN);
	}
	}
	return NULL;
	}

	/* this function parses verifier file. Format is:
	* string(index):base64(N):base64(g):0
	* string(username):base64(v):base64(salt):int(index)
	*/


	int SRP_VBASE_init(SRP_VBASE vb, char verifier_file)
	{
	int error_code ;
	STACK_OF(SRP_gN) *SRP_gN_tab = sk_SRP_gN_new_null();
	char *last_index = NULL;
	int i;
	char **pp;

	SRP_gN *gN = NULL;
	SRP_user_pwd *user_pwd = NULL ;

	TXT_DB *tmpdb = NULL;
	BIO *in = BIO_new(BIO_s_file());

	error_code = SRP_ERR_OPEN_FILE;

	if (in == NULL \|\| BIO_read_filename(in,verifier_file) <= 0)
	goto err;

	error_code = SRP_ERR_VBASE_INCOMPLETE_FILE;

	if ((tmpdb =TXT_DB_read(in,DB_NUMBER)) == NULL)
	goto err;

	error_code = SRP_ERR_MEMORY;


	if (vb->seed_key)
	{
	last_index = SRP_get_default_gN(NULL)->id;
	}
	for (i = 0; i < sk_OPENSSL_PSTRING_num(tmpdb->data); i++)
	{
	pp = sk_OPENSSL_PSTRING_value(tmpdb->data,i);
	if (pp[DB_srptype][0] == DB_SRP_INDEX)
	{
	/we add this couple in the internal Stack /

	if ((gN = (SRP_gN *)OPENSSL_malloc(sizeof(SRP_gN))) == NULL)
	goto err;

	if (!(gN->id = BUF_strdup(pp[DB_srpid]))
	\|\| !(gN->N = SRP_gN_place_bn(vb->gN_cache,pp[DB_srpverifier]))
	\|\| !(gN->g = SRP_gN_place_bn(vb->gN_cache,pp[DB_srpsalt]))
	\|\| sk_SRP_gN_insert(SRP_gN_tab,gN,0) == 0)
	goto err;

	gN = NULL;

	if (vb->seed_key != NULL)
	{
	last_index = pp[DB_srpid];
	}
	}
	else if (pp[DB_srptype][0] == DB_SRP_VALID)
	{
	/* it is a user .... */
	SRP_gN *lgN;
	if ((lgN = SRP_get_gN_by_id(pp[DB_srpgN],SRP_gN_tab))!=NULL)
	{
	error_code = SRP_ERR_MEMORY;
	if ((user_pwd = SRP_user_pwd_new()) == NULL)
	goto err;

	SRP_user_pwd_set_gN(user_pwd,lgN->g,lgN->N);
	if (!SRP_user_pwd_set_ids(user_pwd, pp[DB_srpid],pp[DB_srpinfo]))
	goto err;

	error_code = SRP_ERR_VBASE_BN_LIB;
	if (!SRP_user_pwd_set_sv(user_pwd, pp[DB_srpsalt],pp[DB_srpverifier]))
	goto err;

	if (sk_SRP_user_pwd_insert(vb->users_pwd, user_pwd, 0) == 0)
	goto err;
	user_pwd = NULL; /* abandon responsability */
	}
	}
	}

	if (last_index != NULL)
	{
	/* this means that we want to simulate a default user */

	if (((gN = SRP_get_gN_by_id(last_index,SRP_gN_tab))==NULL))
	{
	error_code = SRP_ERR_VBASE_BN_LIB;
	goto err;
	}
	vb->default_g = gN->g ;
	vb->default_N = gN->N ;
	gN = NULL ;
	}
	error_code = SRP_NO_ERROR;

	err:
	/* there may be still some leaks to fix, if this fails, the application terminates most likely */

	if (gN != NULL)
	{
	OPENSSL_free(gN->id);
	OPENSSL_free(gN);
	}

	SRP_user_pwd_free(user_pwd);

	if (tmpdb) TXT_DB_free(tmpdb);
	if (in) BIO_free_all(in);

	sk_SRP_gN_free(SRP_gN_tab);

	return error_code;

	}


	SRP_user_pwd SRP_VBASE_get_by_user(SRP_VBASE vb, char *username)
	{
	int i;
	SRP_user_pwd *user;
	unsigned char digv[SHA_DIGEST_LENGTH];
	unsigned char digs[SHA_DIGEST_LENGTH];
	EVP_MD_CTX ctxt;

	if (vb == NULL)
	return NULL;
	for(i = 0; i < sk_SRP_user_pwd_num(vb->users_pwd); i++)
	{
	user = sk_SRP_user_pwd_value(vb->users_pwd, i);
	if (strcmp(user->id,username)==0)
	return user;
	}
	if ((vb->seed_key == NULL) \|\|
	(vb->default_g == NULL) \|\|
	(vb->default_N == NULL))
	return NULL;

	/* if the user is unknown we set parameters as well if we have a seed_key */

	if ((user = SRP_user_pwd_new()) == NULL)
	return NULL;

	SRP_user_pwd_set_gN(user,vb->default_g,vb->default_N);

	if (!SRP_user_pwd_set_ids(user,username,NULL))
	goto err;

	RAND_pseudo_bytes(digv, SHA_DIGEST_LENGTH);
	EVP_MD_CTX_init(&ctxt);
	EVP_DigestInit_ex(&ctxt, EVP_sha1(), NULL);
	EVP_DigestUpdate(&ctxt, vb->seed_key, strlen(vb->seed_key));
	EVP_DigestUpdate(&ctxt, username, strlen(username));
	EVP_DigestFinal_ex(&ctxt, digs, NULL);
	EVP_MD_CTX_cleanup(&ctxt);
	if (SRP_user_pwd_set_sv_BN(user, BN_bin2bn(digs,SHA_DIGEST_LENGTH,NULL), BN_bin2bn(digv,SHA_DIGEST_LENGTH, NULL)))
	return user;

	err: SRP_user_pwd_free(user);
	return NULL;
	}


	/*
	create a verifier (salt,verifier,g and N are in base64)
	*/
	char SRP_create_verifier(const char user, const char pass, char *salt,
	char *verifier, const char N, const char *g)
	{
	int len;
	char * result=NULL;
	char *vf;
	BIGNUM N_bn = NULL, g_bn = NULL, s = NULL, v = NULL;
	unsigned char tmp[MAX_LEN];
	unsigned char tmp2[MAX_LEN];
	char * defgNid = NULL;

	if ((user == NULL)\|\|
	(pass == NULL)\|\|
	(salt == NULL)\|\|
	(verifier == NULL))
	goto err;

	if (N)
	{
	if (!(len = t_fromb64(tmp, N))) goto err;
	N_bn = BN_bin2bn(tmp, len, NULL);
	if (!(len = t_fromb64(tmp, g))) goto err;
	g_bn = BN_bin2bn(tmp, len, NULL);
	defgNid = "*";
	}
	else
	{
	SRP_gN * gN = SRP_get_gN_by_id(g, NULL) ;
	if (gN == NULL)
	goto err;
	N_bn = gN->N;
	g_bn = gN->g;
	defgNid = gN->id;
	}

	if (*salt == NULL)
	{
	RAND_pseudo_bytes(tmp2, SRP_RANDOM_SALT_LEN);

	s = BN_bin2bn(tmp2, SRP_RANDOM_SALT_LEN, NULL);
	}
	else
	{
	if (!(len = t_fromb64(tmp2, *salt)))
	goto err;
	s = BN_bin2bn(tmp2, len, NULL);
	}


	if(!SRP_create_verifier_BN(user, pass, &s, &v, N_bn, g_bn)) goto err;

	BN_bn2bin(v,tmp);
	if (((vf = OPENSSL_malloc(BN_num_bytes(v)*2)) == NULL))
	goto err;
	t_tob64(vf, tmp, BN_num_bytes(v));

	*verifier = vf;
	if (*salt == NULL)
	{
	char *tmp_salt;

	if ((tmp_salt = OPENSSL_malloc(SRP_RANDOM_SALT_LEN * 2)) == NULL)
	{
	OPENSSL_free(vf);
	goto err;
	}
	t_tob64(tmp_salt, tmp2, SRP_RANDOM_SALT_LEN);
	*salt = tmp_salt;
	}

	result=defgNid;

	err:
	if(N)
	{
	BN_free(N_bn);
	BN_free(g_bn);
	}
	return result;
	}

	/*
	create a verifier (salt,verifier,g and N are BIGNUMs)
	*/
	int SRP_create_verifier_BN(const char user, const char pass, BIGNUM salt, BIGNUM verifier, BIGNUM N, BIGNUM g)
	{
	int result=0;
	BIGNUM *x = NULL;
	BN_CTX *bn_ctx = BN_CTX_new();
	unsigned char tmp2[MAX_LEN];

	if ((user == NULL)\|\|
	(pass == NULL)\|\|
	(salt == NULL)\|\|
	(verifier == NULL)\|\|
	(N == NULL)\|\|
	(g == NULL)\|\|
	(bn_ctx == NULL))
	goto err;

	srp_bn_print(N);
	srp_bn_print(g);

	if (*salt == NULL)
	{
	RAND_pseudo_bytes(tmp2, SRP_RANDOM_SALT_LEN);

	*salt = BN_bin2bn(tmp2,SRP_RANDOM_SALT_LEN,NULL);
	}

	x = SRP_Calc_x(*salt,user,pass);

	*verifier = BN_new();
	if(*verifier == NULL) goto err;

	if (!BN_mod_exp(*verifier,g,x,N,bn_ctx))
	{
	BN_clear_free(*verifier);
	goto err;
	}

	srp_bn_print(*verifier);

	result=1;

	err:

	BN_clear_free(x);
	BN_CTX_free(bn_ctx);
	return result;
	}



	#endif