initial commit
Tom Cocagne
commit
7ec0c6c2ae
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@ -0,0 +1,569 @@
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/*
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* Secure Remote Password 6a implementation
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* Copyright (c) 2010 Tom Cocagne. All rights reserved.
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* http://csrp.googlecode.com/p/csrp/
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions are met:
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* * Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* * Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* * Neither the name of the Google Code nor the
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* names of its contributors may be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL TOM COCAGNE BE LIABLE FOR ANY
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* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
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* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
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* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*
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*/
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#ifdef WIN32
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#include <Wincrypt.h>
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#else
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#include <sys/time.h>
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#endif
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#include <alloca.h>
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#include <stdlib.h>
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#include <string.h>
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#include <stdio.h>
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#include <openssl/bn.h>
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#include <openssl/sha.h>
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#include <openssl/crypto.h>
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#include <openssl/rand.h>
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#include "srp.h"
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/* 2048-bit prime & generator pair from RFC 5054 */
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#define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#define G_HEX "2"
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static const BIGNUM * N = 0;
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static const BIGNUM * g = 0;
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static const BIGNUM * k = 0;
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static int g_initialized = 0;
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struct SRPVerifier
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{
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const char * username;
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const unsigned char * bytes_B;
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int authenticated;
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unsigned char M [SRP_SHA256_DIGEST_LENGTH];
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unsigned char H_AMK [SRP_SHA256_DIGEST_LENGTH];
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unsigned char session_key [SRP_SHA256_DIGEST_LENGTH];
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};
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struct SRPUser
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{
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BIGNUM *a;
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BIGNUM *A;
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BIGNUM *S;
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const unsigned char * bytes_A;
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int authenticated;
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const char * username;
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const unsigned char * password;
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int password_len;
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unsigned char M [SRP_SHA256_DIGEST_LENGTH];
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unsigned char H_AMK [SRP_SHA256_DIGEST_LENGTH];
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unsigned char session_key [SRP_SHA256_DIGEST_LENGTH];
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};
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static BIGNUM * H_nn( const BIGNUM * n1, const BIGNUM * n2 )
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{
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unsigned char buff[ SHA256_DIGEST_LENGTH ];
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int len_n1 = BN_num_bytes(n1);
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int len_n2 = BN_num_bytes(n2);
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int nbytes = len_n1 + len_n2;
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unsigned char * bin = (unsigned char *) alloca( nbytes );
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BN_bn2bin(n1, bin);
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BN_bn2bin(n2, bin + len_n1);
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SHA256( bin, nbytes, buff );
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return BN_bin2bn(buff, SHA256_DIGEST_LENGTH, NULL);
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}
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static BIGNUM * H_ns( const BIGNUM * n, const unsigned char * bytes, int len_bytes )
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{
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unsigned char buff[ SHA256_DIGEST_LENGTH ];
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int len_n = BN_num_bytes(n);
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int nbytes = len_n + len_bytes;
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unsigned char * bin = (unsigned char *) alloca( nbytes );
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BN_bn2bin(n, bin);
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memcpy( bin + len_n, bytes, len_bytes );
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SHA256( bin, nbytes, buff );
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return BN_bin2bn(buff, SHA256_DIGEST_LENGTH, NULL);
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}
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static BIGNUM * calculate_x( const BIGNUM * salt, const char * username, const unsigned char * password, int password_len )
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{
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unsigned char ucp_hash[SHA256_DIGEST_LENGTH];
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SHA256_CTX ctx;
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SHA256_Init( &ctx );
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SHA256_Update( &ctx, username, strlen(username) );
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SHA256_Update( &ctx, ":", 1 );
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SHA256_Update( &ctx, password, password_len );
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SHA256_Final( ucp_hash, &ctx );
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return H_ns( salt, ucp_hash, sizeof(ucp_hash) );
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}
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static void update_hash( SHA256_CTX *ctx, const BIGNUM * n )
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{
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unsigned long len = BN_num_bytes(n);
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unsigned char * n_bytes = (unsigned char *) alloca( len );
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BN_bn2bin(n, n_bytes);
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SHA256_Update(ctx, n_bytes, len);
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}
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static void hash_num( const BIGNUM * n, unsigned char * dest )
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{
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int nbytes = BN_num_bytes(n);
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unsigned char * bin = (unsigned char *) alloca( nbytes );
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BN_bn2bin(n, bin);
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SHA256( bin, nbytes, dest );
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}
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static void calculate_M( unsigned char * dest, const char * I, const BIGNUM * s,
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const BIGNUM * A, const BIGNUM * B, const unsigned char * K )
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{
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unsigned char H_N[ SHA256_DIGEST_LENGTH ];
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unsigned char H_g[ SHA256_DIGEST_LENGTH ];
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unsigned char H_I[ SHA256_DIGEST_LENGTH ];
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unsigned char H_xor[ SHA256_DIGEST_LENGTH ];
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SHA256_CTX ctx;
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int i = 0;
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hash_num( N, H_N );
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hash_num( g, H_g );
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SHA256((const unsigned char *)I, strlen(I), H_I);
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for (i=0; i < SHA256_DIGEST_LENGTH; i++ )
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H_xor[i] = H_N[i] ^ H_g[i];
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SHA256_Init( &ctx );
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SHA256_Update( &ctx, H_xor, sizeof(H_xor) );
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SHA256_Update( &ctx, H_I, sizeof(H_I) );
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update_hash( &ctx, s );
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update_hash( &ctx, A );
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update_hash( &ctx, B );
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SHA256_Update( &ctx, K, SHA256_DIGEST_LENGTH );
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SHA256_Final( dest, &ctx );
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}
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static void calculate_H_AMK( unsigned char *dest, const BIGNUM * A, const unsigned char * M, const unsigned char * K )
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{
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SHA256_CTX ctx;
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SHA256_Init( &ctx );
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update_hash( &ctx, A );
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SHA256_Update( &ctx, M, SHA256_DIGEST_LENGTH);
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SHA256_Update( &ctx, K, SHA256_DIGEST_LENGTH);
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SHA256_Final( dest, &ctx );
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}
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/***********************************************************************************************************
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*
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* Exported Functions
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*
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***********************************************************************************************************/
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void srp_init()
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{
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#ifdef WIN32
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HCRYPTPROV wctx;
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#else
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FILE *fp = 0;
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#endif
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unsigned char buff[32];
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BIGNUM *tN = BN_new();
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BIGNUM *tg = BN_new();
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BN_hex2bn( &tN, N_HEX );
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BN_hex2bn( &tg, G_HEX );
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N = tN;
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g = tg;
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k = H_nn(N,g);
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#ifdef WIN32
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CryptAcquireContext(&wctx, NULL, NULL, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT);
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CryptGenRandom(wctx, sizeof(buff), (BYTE*) buff);
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CryptReleaseContext(wctx, 0);
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#else
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fp = fopen("/dev/urandom", "r");
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if (fp)
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{
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fread(buff, sizeof(buff), 1, fp);
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fclose(fp);
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}
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else
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{
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/* Dirty... but better than nothing. */
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gettimeofday( (struct timeval *)buff, 0);
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}
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#endif
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RAND_seed( buff, sizeof(buff) );
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g_initialized = 1;
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}
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void srp_fini()
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{
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g_initialized = 0;
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BN_free((BIGNUM *)N);
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BN_free((BIGNUM *)g);
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BN_free((BIGNUM *)k);
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N = 0;
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g = 0;
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}
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int srp_is_initialized()
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{
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return g_initialized;
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}
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void srp_gen_sv( const char * username,
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const unsigned char * password, int len_password,
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const unsigned char ** bytes_s, int * len_s,
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const unsigned char ** bytes_v, int * len_v )
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{
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BIGNUM * s = BN_new();
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BIGNUM * v = BN_new();
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BIGNUM * x = 0;
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BN_CTX *ctx = BN_CTX_new();
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BN_rand(s, 32, -1, 0);
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x = calculate_x( s, username, password, len_password );
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BN_mod_exp(v, g, x, N, ctx);
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*len_s = BN_num_bytes(s);
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*len_v = BN_num_bytes(v);
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*bytes_s = (const unsigned char *) malloc( *len_s );
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*bytes_v = (const unsigned char *) malloc( *len_v );
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BN_bn2bin(s, (unsigned char *) *bytes_s);
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BN_bn2bin(v, (unsigned char *) *bytes_v);
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BN_free(s);
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BN_free(v);
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BN_free(x);
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BN_CTX_free(ctx);
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}
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/* Out: bytes_B, len_B.
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*
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* On failure, bytes_B will be set to NULL and len_B will be set to 0
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*/
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struct SRPVerifier * srp_verifier_new( const char * username,
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const unsigned char * bytes_s, int len_s,
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const unsigned char * bytes_v, int len_v,
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const unsigned char * bytes_A, int len_A,
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const unsigned char ** bytes_B, int * len_B)
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{
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BIGNUM *s = BN_bin2bn(bytes_s, len_s, NULL);
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BIGNUM *v = BN_bin2bn(bytes_v, len_v, NULL);
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BIGNUM *A = BN_bin2bn(bytes_A, len_A, NULL);
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BIGNUM *u = 0;
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BIGNUM *B = BN_new();
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BIGNUM *S = BN_new();
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BIGNUM *b = BN_new();
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BIGNUM *tmp1 = BN_new();
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BIGNUM *tmp2 = BN_new();
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BN_CTX *ctx = BN_CTX_new();
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int ulen = strlen(username) + 1;
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struct SRPVerifier * ver = (struct SRPVerifier *) malloc( sizeof(struct SRPVerifier) );
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ver->username = (char *) malloc( ulen );
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memcpy( (char*)ver->username, username, ulen );
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ver->authenticated = 0;
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/* SRP-6a safety check */
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BN_mod(tmp1, A, N, ctx);
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if ( !BN_is_zero(tmp1) )
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{
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BN_rand(b, 256, -1, 0);
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/* B = kv + g^b */
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BN_mul(tmp1, k, v, ctx);
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BN_mod_exp(tmp2, g, b, N, ctx);
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BN_add(B, tmp1, tmp2);
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u = H_nn(A,B);
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/* S = (A *(v^u)) ^ b */
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BN_mod_exp(tmp1, v, u, N, ctx);
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BN_mul(tmp2, A, tmp1, ctx);
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BN_mod_exp(S, tmp2, b, N, ctx);
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hash_num(S, ver->session_key);
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calculate_M( ver->M, username, s, A, B, ver->session_key );
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calculate_H_AMK( ver->H_AMK, A, ver->M, ver->session_key );
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*len_B = BN_num_bytes(B);
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*bytes_B = malloc( *len_B );
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BN_bn2bin( B, (unsigned char *) *bytes_B );
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ver->bytes_B = *bytes_B;
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}
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else
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{
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*len_B = 0;
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*bytes_B = NULL;
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}
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BN_free(s);
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BN_free(v);
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BN_free(A);
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if (u) BN_free(u);
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BN_free(B);
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BN_free(S);
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BN_free(b);
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BN_free(tmp1);
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BN_free(tmp2);
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BN_CTX_free(ctx);
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return ver;
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}
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||||
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||||
|
||||
|
||||
void srp_verifier_delete( struct SRPVerifier * ver )
|
||||
{
|
||||
free( (char *) ver->username );
|
||||
free( (unsigned char *) ver->bytes_B );
|
||||
free( ver );
|
||||
}
|
||||
|
||||
|
||||
|
||||
int srp_verifier_is_authenticated( struct SRPVerifier * ver )
|
||||
{
|
||||
return ver->authenticated;
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||||
}
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||||
|
||||
|
||||
const char * srp_verifier_get_username( struct SRPVerifier * ver )
|
||||
{
|
||||
return ver->username;
|
||||
}
|
||||
|
||||
/* Key length is SRP_SHA256_DIGEST_LENGTH */
|
||||
const unsigned char * srp_verifier_get_session_key( struct SRPVerifier * ver )
|
||||
{
|
||||
return ver->session_key;
|
||||
}
|
||||
|
||||
|
||||
|
||||
/* user_M must be exactly SRP_SHA256_DIGEST_LENGTH bytes in size */
|
||||
void srp_verifier_verify_session( struct SRPVerifier * ver, const unsigned char * user_M, const unsigned char ** bytes_HAMK )
|
||||
{
|
||||
if ( memcmp( ver->M, user_M, SRP_SHA256_DIGEST_LENGTH ) == 0 )
|
||||
{
|
||||
ver->authenticated = 1;
|
||||
*bytes_HAMK = ver->H_AMK;
|
||||
}
|
||||
else
|
||||
*bytes_HAMK = NULL;
|
||||
}
|
||||
|
||||
/*******************************************************************************/
|
||||
|
||||
struct SRPUser * srp_user_new( const char * username,
|
||||
const unsigned char * bytes_password, int len_password )
|
||||
{
|
||||
struct SRPUser *usr = (struct SRPUser *) malloc( sizeof(struct SRPUser) );
|
||||
int ulen = strlen(username) + 1;
|
||||
|
||||
usr->a = BN_new();
|
||||
usr->A = BN_new();
|
||||
usr->S = BN_new();
|
||||
|
||||
usr->username = (const char *) malloc(ulen);
|
||||
usr->password = (const unsigned char *) malloc(len_password);
|
||||
usr->password_len = len_password;
|
||||
|
||||
memcpy((char *)usr->username, username, ulen);
|
||||
memcpy((char *)usr->password, bytes_password, len_password);
|
||||
|
||||
usr->bytes_A = 0;
|
||||
|
||||
return usr;
|
||||
}
|
||||
|
||||
|
||||
|
||||
void srp_user_delete( struct SRPUser * usr )
|
||||
{
|
||||
BN_free( usr->a );
|
||||
BN_free( usr->A );
|
||||
BN_free( usr->S );
|
||||
|
||||
free((char *)usr->username);
|
||||
free((char *)usr->password);
|
||||
|
||||
if (usr->bytes_A)
|
||||
free( (char *)usr->bytes_A );
|
||||
|
||||
free( usr );
|
||||
}
|
||||
|
||||
|
||||
|
||||
int srp_user_is_authenticated( struct SRPUser * usr)
|
||||
{
|
||||
return usr->authenticated;
|
||||
}
|
||||
|
||||
|
||||
const char * srp_user_get_username( struct SRPUser * usr )
|
||||
{
|
||||
return usr->username;
|
||||
}
|
||||
|
||||
|
||||
|
||||
/* Key length is SRP_SHA256_DIGEST_LENGTH */
|
||||
const unsigned char * srp_user_get_session_key( struct SRPUser * usr )
|
||||
{
|
||||
return usr->session_key;
|
||||
}
|
||||
|
||||
/* Output: username, bytes_A, len_A */
|
||||
void srp_user_start_authentication( struct SRPUser * usr, const char ** username,
|
||||
const unsigned char ** bytes_A, int * len_A )
|
||||
{
|
||||
BN_CTX *ctx = BN_CTX_new();
|
||||
|
||||
BN_rand(usr->a, 256, -1, 0);
|
||||
|
||||
BN_mod_exp(usr->A, g, usr->a, N, ctx);
|
||||
|
||||
BN_CTX_free(ctx);
|
||||
|
||||
*len_A = BN_num_bytes(usr->A);
|
||||
*bytes_A = malloc( *len_A );
|
||||
|
||||
BN_bn2bin( usr->A, (unsigned char *) *bytes_A );
|
||||
|
||||
usr->bytes_A = *bytes_A;
|
||||
*username = usr->username;
|
||||
}
|
||||
|
||||
|
||||
/* Output: bytes_M. Buffer length is SRP_SHA256_DIGEST_LENGTH */
|
||||
void srp_user_process_challenge( struct SRPUser * usr,
|
||||
const unsigned char * bytes_s, int len_s,
|
||||
const unsigned char * bytes_B, int len_B,
|
||||
const unsigned char ** bytes_M )
|
||||
{
|
||||
BIGNUM *s = BN_bin2bn(bytes_s, len_s, NULL);
|
||||
BIGNUM *B = BN_bin2bn(bytes_B, len_B, NULL);
|
||||
BIGNUM *u = 0;
|
||||
BIGNUM *x = 0;
|
||||
BIGNUM *v = BN_new();
|
||||
BIGNUM *tmp1 = BN_new();
|
||||
BIGNUM *tmp2 = BN_new();
|
||||
BIGNUM *tmp3 = BN_new();
|
||||
BN_CTX *ctx = BN_CTX_new();
|
||||
|
||||
u = H_nn(usr->A,B);
|
||||
|
||||
x = calculate_x( s, usr->username, usr->password, usr->password_len );
|
||||
|
||||
/* SRP-6a safety check */
|
||||
if ( !BN_is_zero(B) && !BN_is_zero(u) )
|
||||
{
|
||||
BN_mod_exp(v, g, x, N, ctx);
|
||||
|
||||
/* S = (B - k*(g^x)) ^ (a + ux) */
|
||||
BN_mul(tmp1, u, x, ctx);
|
||||
BN_add(tmp2, usr->a, tmp1); /* tmp2 = (a + ux) */
|
||||
BN_mod_exp(tmp1, g, x, N, ctx);
|
||||
BN_mul(tmp3, k, tmp1, ctx); /* tmp3 = k*(g^x) */
|
||||
BN_sub(tmp1, B, tmp3); /* tmp1 = (B - K*(g^x)) */
|
||||
BN_mod_exp(usr->S, tmp1, tmp2, N, ctx);
|
||||
|
||||
hash_num(usr->S, usr->session_key);
|
||||
|
||||
calculate_M( usr->M, usr->username, s, usr->A, B, usr->session_key );
|
||||
calculate_H_AMK( usr->H_AMK, usr->A, usr->M, usr->session_key );
|
||||
|
||||
*bytes_M = usr->M;
|
||||
}
|
||||
else
|
||||
{
|
||||
*bytes_M = NULL;
|
||||
}
|
||||
|
||||
BN_free(s);
|
||||
BN_free(B);
|
||||
BN_free(u);
|
||||
BN_free(x);
|
||||
BN_free(v);
|
||||
BN_free(tmp1);
|
||||
BN_free(tmp2);
|
||||
BN_free(tmp3);
|
||||
BN_CTX_free(ctx);
|
||||
}
|
||||
|
||||
/* bytes_HAMK must be exactly SRP_SHA256_DIGEST_LENGTH bytes in size */
|
||||
void srp_user_verify_session( struct SRPUser * usr, const unsigned char * bytes_HAMK )
|
||||
{
|
||||
if ( memcmp( usr->H_AMK, bytes_HAMK, SRP_SHA256_DIGEST_LENGTH ) == 0 )
|
||||
usr->authenticated = 1;
|
||||
}
|
||||
|
|
@ -0,0 +1,137 @@
|
|||
/*
|
||||
* Secure Remote Password 6a implementation
|
||||
* Copyright (c) 2010 Tom Cocagne. All rights reserved.
|
||||
* http://csrp.googlecode.com/p/csrp/
|
||||
*
|
||||
* 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 Google Code 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 TOM COCAGNE 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.
|
||||
*
|
||||
*/
|
||||
|
||||
/*
|
||||
*
|
||||
* Purpose: This is a direct implementation of the Secure Remote Password
|
||||
* Protocol version 6a as described by
|
||||
* http://srp.stanford.edu/design.html
|
||||
*
|
||||
* Author: tom.cocagne@gmail.com (Tom Cocagne)
|
||||
*
|
||||
* Dependencies: OpenSSL (and Advapi32.lib on Windows)
|
||||
*
|
||||
* Usage: Refer to test_srp.c for a demonstration
|
||||
*
|
||||
* Note:
|
||||
* The SRP protocol does not mandate a specific hashing algorithm. This
|
||||
* implementation uses SHA256 rather than SHA1 for additional security
|
||||
* and the increased number of bytes in the resulting shared key. However,
|
||||
* SHA256 is approximately 20% slower than SHA1. If speed is more important
|
||||
* than the key length and/or added security, you may change it to SHA1.
|
||||
*
|
||||
*/
|
||||
|
||||
#ifndef SRP_H
|
||||
#define SRP_H
|
||||
|
||||
#define SRP_SHA256_DIGEST_LENGTH 32
|
||||
|
||||
/* srp_init() must be called prior to usage of any other srp_* functions.
|
||||
* and a matching srp_fini() will clean up all memory allocated by srp_init().
|
||||
*/
|
||||
void srp_init();
|
||||
void srp_fini();
|
||||
|
||||
/* Returns 1 if srp_init() if the library is initialized */
|
||||
int srp_is_initialized();
|
||||
|
||||
|
||||
struct SRPVerifier;
|
||||
struct SRPUser;
|
||||
|
||||
|
||||
/* Out: bytes_s, len_s, bytes_v, len_v
|
||||
*
|
||||
* The caller is responsible for freeing the memory allocated for bytes_s and bytes_v
|
||||
*/
|
||||
void srp_gen_sv( const char * username,
|
||||
const unsigned char * password, int len_password,
|
||||
const unsigned char ** bytes_s, int * len_s,
|
||||
const unsigned char ** bytes_v, int * len_v );
|
||||
|
||||
|
||||
/* Out: bytes_B, len_B.
|
||||
*
|
||||
* On failure, bytes_B will be set to NULL and len_B will be set to 0
|
||||
*/
|
||||
struct SRPVerifier * srp_verifier_new( const char * username,
|
||||
const unsigned char * bytes_s, int len_s,
|
||||
const unsigned char * bytes_v, int len_v,
|
||||
const unsigned char * bytes_A, int len_A,
|
||||
const unsigned char ** bytes_B, int * len_B);
|
||||
|
||||
|
||||
void srp_verifier_delete( struct SRPVerifier * ver );
|
||||
|
||||
|
||||
int srp_verifier_is_authenticated( struct SRPVerifier * ver );
|
||||
|
||||
|
||||
const char * srp_verifier_get_username( struct SRPVerifier * ver );
|
||||
|
||||
|
||||
/* Key length is SRP_SHA256_DIGEST_LENGTH */
|
||||
const unsigned char * srp_verifier_get_session_key( struct SRPVerifier * ver );
|
||||
|
||||
|
||||
/* user_M must be exactly SRP_SHA256_DIGEST_LENGTH bytes in size */
|
||||
void srp_verifier_verify_session( struct SRPVerifier * ver,
|
||||
const unsigned char * user_M,
|
||||
const unsigned char ** bytes_HAMK );
|
||||
|
||||
/*******************************************************************************/
|
||||
|
||||
struct SRPUser * srp_user_new( const char * username,
|
||||
const unsigned char * bytes_password, int len_password );
|
||||
|
||||
void srp_user_delete( struct SRPUser * usr );
|
||||
|
||||
int srp_user_is_authenticated( struct SRPUser * usr);
|
||||
|
||||
|
||||
const char * srp_user_get_username( struct SRPUser * usr );
|
||||
|
||||
/* Key length is SRP_SHA256_DIGEST_LENGTH */
|
||||
const unsigned char * srp_user_get_session_key( struct SRPUser * usr );
|
||||
|
||||
/* Output: username, bytes_A, len_A */
|
||||
void srp_user_start_authentication( struct SRPUser * usr, const char ** username,
|
||||
const unsigned char ** bytes_A, int * len_A );
|
||||
|
||||
/* Output: bytes_M. Buffer length is SRP_SHA256_DIGEST_LENGTH */
|
||||
void srp_user_process_challenge( struct SRPUser * usr,
|
||||
const unsigned char * bytes_s, int len_s,
|
||||
const unsigned char * bytes_B, int len_B,
|
||||
const unsigned char ** bytes_M );
|
||||
|
||||
/* bytes_HAMK must be exactly SRP_SHA256_DIGEST_LENGTH bytes in size */
|
||||
void srp_user_verify_session( struct SRPUser * usr, const unsigned char * bytes_HAMK );
|
||||
|
||||
#endif /* Include Guard */
|
||||
|
|
@ -0,0 +1,115 @@
|
|||
#include <stdio.h>
|
||||
#include <stdlib.h>
|
||||
#include <string.h>
|
||||
#include <sys/time.h>
|
||||
|
||||
|
||||
#include "srp.h"
|
||||
|
||||
|
||||
#define NITER 100
|
||||
|
||||
|
||||
unsigned long long get_usec()
|
||||
{
|
||||
struct timeval t;
|
||||
gettimeofday(&t, NULL);
|
||||
return (((unsigned long long)t.tv_sec) * 1000000) + t.tv_usec;
|
||||
}
|
||||
|
||||
|
||||
int main( int argc, char * argv[] )
|
||||
{
|
||||
struct SRPVerifier * ver;
|
||||
struct SRPUser * usr;
|
||||
|
||||
const unsigned char * bytes_s = 0;
|
||||
const unsigned char * bytes_v = 0;
|
||||
const unsigned char * bytes_A = 0;
|
||||
const unsigned char * bytes_B = 0;
|
||||
|
||||
const unsigned char * bytes_M = 0;
|
||||
const unsigned char * bytes_HAMK = 0;
|
||||
|
||||
int len_s = 0;
|
||||
int len_v = 0;
|
||||
int len_A = 0;
|
||||
int len_B = 0;
|
||||
int i;
|
||||
|
||||
unsigned long long start;
|
||||
unsigned long long duration;
|
||||
|
||||
const char * username = "testuser";
|
||||
const char * password = "password";
|
||||
|
||||
const char * auth_username = 0;
|
||||
|
||||
srp_init(NULL,0);
|
||||
|
||||
srp_gen_sv( username, password, strlen(password),
|
||||
&bytes_s, &len_s, &bytes_v, &len_v );
|
||||
|
||||
|
||||
|
||||
start = get_usec();
|
||||
|
||||
for( i = 0; i < NITER; i++ )
|
||||
{
|
||||
usr = srp_user_new( username, password, strlen(password) );
|
||||
|
||||
srp_user_start_authentication( usr, &auth_username, &bytes_A, &len_A );
|
||||
|
||||
/* User -> Host: (username, bytes_A) */
|
||||
ver = srp_verifier_new( username, bytes_s, len_s, bytes_v, len_v,
|
||||
bytes_A, len_A, & bytes_B, &len_B );
|
||||
|
||||
if ( !bytes_B )
|
||||
{
|
||||
printf("Verifier SRP-6a safety check violated!\n");
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
/* Host -> User: (bytes_s, bytes_B) */
|
||||
srp_user_process_challenge( usr, bytes_s, len_s, bytes_B, len_B, &bytes_M );
|
||||
|
||||
if ( !bytes_M )
|
||||
{
|
||||
printf("User SRP-6a safety check violation!\n");
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
/* User -> Host: (bytes_M) */
|
||||
srp_verifier_verify_session( ver, bytes_M, &bytes_HAMK );
|
||||
|
||||
if ( !bytes_HAMK )
|
||||
{
|
||||
printf("User authentication failed!\n");
|
||||
goto cleanup;
|
||||
}
|
||||
|
||||
/* Host -> User: (HAMK) */
|
||||
srp_user_verify_session( usr, bytes_HAMK );
|
||||
|
||||
if ( !srp_user_is_authenticated(usr) )
|
||||
{
|
||||
printf("Server authentication failed!\n");
|
||||
}
|
||||
|
||||
cleanup:
|
||||
srp_verifier_delete( ver );
|
||||
srp_user_delete( usr );
|
||||
}
|
||||
|
||||
duration = get_usec() - start;
|
||||
|
||||
printf("Usec per call: %d\n", (int)(duration / NITER));
|
||||
|
||||
|
||||
free( (char *)bytes_s );
|
||||
free( (char *)bytes_v );
|
||||
|
||||
srp_fini();
|
||||
|
||||
return 0;
|
||||
}
|
||||
Loading…
Reference in New Issue