| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207208209210211212213214215216217218219220221222223224225226227228229230231 | /* *  Example ECDSA program * *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved *  SPDX-License-Identifier: Apache-2.0 * *  Licensed under the Apache License, Version 2.0 (the "License"); you may *  not use this file except in compliance with the License. *  You may obtain a copy of the License at * *  http://www.apache.org/licenses/LICENSE-2.0 * *  Unless required by applicable law or agreed to in writing, software *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *  See the License for the specific language governing permissions and *  limitations under the License. * *  This file is part of mbed TLS (https://tls.mbed.org) */#if !defined(MBEDTLS_CONFIG_FILE)#include "mbedtls/config.h"#else#include MBEDTLS_CONFIG_FILE#endif#if defined(MBEDTLS_PLATFORM_C)#include "mbedtls/platform.h"#else#include <stdio.h>#define mbedtls_printf     printf#endif#if defined(MBEDTLS_ECDSA_C) && \    defined(MBEDTLS_ENTROPY_C) && defined(MBEDTLS_CTR_DRBG_C)#include "mbedtls/entropy.h"#include "mbedtls/ctr_drbg.h"#include "mbedtls/ecdsa.h"#include <string.h>#endif/* * Uncomment to show key and signature details */#define VERBOSE/* * Uncomment to force use of a specific curve */#define ECPARAMS    MBEDTLS_ECP_DP_SECP192R1#if !defined(ECPARAMS)#define ECPARAMS    mbedtls_ecp_curve_list()->grp_id#endif#if !defined(MBEDTLS_ECDSA_C) || !defined(MBEDTLS_SHA256_C) || \    !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C)int main( void ){    mbedtls_printf("MBEDTLS_ECDSA_C and/or MBEDTLS_SHA256_C and/or "           "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C not defined\n");    return( 0 );}#else#if defined(VERBOSE)static void dump_buf( const char *title, unsigned char *buf, size_t len ){    size_t i;    mbedtls_printf( "%s", title );    for( i = 0; i < len; i++ )        mbedtls_printf("%c%c", "0123456789ABCDEF" [buf[i] / 16],                       "0123456789ABCDEF" [buf[i] % 16] );    mbedtls_printf( "\n" );}static void dump_pubkey( const char *title, mbedtls_ecdsa_context *key ){    unsigned char buf[300];    size_t len;    if( mbedtls_ecp_point_write_binary( &key->grp, &key->Q,                MBEDTLS_ECP_PF_UNCOMPRESSED, &len, buf, sizeof buf ) != 0 )    {        mbedtls_printf("internal error\n");        return;    }    dump_buf( title, buf, len );}#else#define dump_buf( a, b, c )#define dump_pubkey( a, b )#endifint main( int argc, char *argv[] ){    int ret;    mbedtls_ecdsa_context ctx_sign, ctx_verify;    mbedtls_entropy_context entropy;    mbedtls_ctr_drbg_context ctr_drbg;    unsigned char hash[] = "This should be the hash of a message.";    unsigned char sig[512];    size_t sig_len;    const char *pers = "ecdsa";    ((void) argv);    mbedtls_ecdsa_init( &ctx_sign );    mbedtls_ecdsa_init( &ctx_verify );    mbedtls_ctr_drbg_init( &ctr_drbg );    memset(sig, 0, sizeof( sig ) );    ret = 1;    if( argc != 1 )    {        mbedtls_printf( "usage: ecdsa\n" );#if defined(_WIN32)        mbedtls_printf( "\n" );#endif        goto exit;    }    /*     * Generate a key pair for signing     */    mbedtls_printf( "\n  . Seeding the random number generator..." );    fflush( stdout );    mbedtls_entropy_init( &entropy );    if( ( ret = mbedtls_ctr_drbg_seed( &ctr_drbg, mbedtls_entropy_func, &entropy,                               (const unsigned char *) pers,                               strlen( pers ) ) ) != 0 )    {        mbedtls_printf( " failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret );        goto exit;    }    mbedtls_printf( " ok\n  . Generating key pair..." );    fflush( stdout );    if( ( ret = mbedtls_ecdsa_genkey( &ctx_sign, ECPARAMS,                              mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )    {        mbedtls_printf( " failed\n  ! mbedtls_ecdsa_genkey returned %d\n", ret );        goto exit;    }    mbedtls_printf( " ok (key size: %d bits)\n", (int) ctx_sign.grp.pbits );    dump_pubkey( "  + Public key: ", &ctx_sign );    /*     * Sign some message hash     */    mbedtls_printf( "  . Signing message..." );    fflush( stdout );    if( ( ret = mbedtls_ecdsa_write_signature( &ctx_sign, MBEDTLS_MD_SHA256,                                       hash, sizeof( hash ),                                       sig, &sig_len,                                       mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 )    {        mbedtls_printf( " failed\n  ! mbedtls_ecdsa_genkey returned %d\n", ret );        goto exit;    }    mbedtls_printf( " ok (signature length = %u)\n", (unsigned int) sig_len );    dump_buf( "  + Hash: ", hash, sizeof hash );    dump_buf( "  + Signature: ", sig, sig_len );    /*     * Transfer public information to verifying context     *     * We could use the same context for verification and signatures, but we     * chose to use a new one in order to make it clear that the verifying     * context only needs the public key (Q), and not the private key (d).     */    mbedtls_printf( "  . Preparing verification context..." );    fflush( stdout );    if( ( ret = mbedtls_ecp_group_copy( &ctx_verify.grp, &ctx_sign.grp ) ) != 0 )    {        mbedtls_printf( " failed\n  ! mbedtls_ecp_group_copy returned %d\n", ret );        goto exit;    }    if( ( ret = mbedtls_ecp_copy( &ctx_verify.Q, &ctx_sign.Q ) ) != 0 )    {        mbedtls_printf( " failed\n  ! mbedtls_ecp_copy returned %d\n", ret );        goto exit;    }    ret = 0;    /*     * Verify signature     */    mbedtls_printf( " ok\n  . Verifying signature..." );    fflush( stdout );    if( ( ret = mbedtls_ecdsa_read_signature( &ctx_verify,                                      hash, sizeof( hash ),                                      sig, sig_len ) ) != 0 )    {        mbedtls_printf( " failed\n  ! mbedtls_ecdsa_read_signature returned %d\n", ret );        goto exit;    }    mbedtls_printf( " ok\n" );exit:#if defined(_WIN32)    mbedtls_printf( "  + Press Enter to exit this program.\n" );    fflush( stdout ); getchar();#endif    mbedtls_ecdsa_free( &ctx_verify );    mbedtls_ecdsa_free( &ctx_sign );    mbedtls_ctr_drbg_free( &ctr_drbg );    mbedtls_entropy_free( &entropy );    return( ret );}#endif /* MBEDTLS_ECDSA_C && MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C &&          ECPARAMS */
 |