diff options
Diffstat (limited to 'programs/pkey/ecdh_curve25519.c')
| -rw-r--r-- | programs/pkey/ecdh_curve25519.c | 210 |
1 files changed, 210 insertions, 0 deletions
diff --git a/programs/pkey/ecdh_curve25519.c b/programs/pkey/ecdh_curve25519.c new file mode 100644 index 000000000..5dd6bddb4 --- /dev/null +++ b/programs/pkey/ecdh_curve25519.c @@ -0,0 +1,210 @@ +/* + * Example ECDHE with Curve25519 program + * + * Copyright The Mbed TLS Contributors + * 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. + */ + +#include "mbedtls/build_info.h" + +#include "mbedtls/platform.h" + +#if !defined(MBEDTLS_ECDH_C) || \ + !defined(MBEDTLS_ECP_DP_CURVE25519_ENABLED) || \ + !defined(MBEDTLS_ENTROPY_C) || !defined(MBEDTLS_CTR_DRBG_C) +int main( void ) +{ + mbedtls_printf( "MBEDTLS_ECDH_C and/or " + "MBEDTLS_ECP_DP_CURVE25519_ENABLED and/or " + "MBEDTLS_ENTROPY_C and/or MBEDTLS_CTR_DRBG_C " + "not defined\n" ); + mbedtls_exit( 0 ); +} +#else + +#include "mbedtls/entropy.h" +#include "mbedtls/ctr_drbg.h" +#include "mbedtls/ecdh.h" + +#include <string.h> + + +int main( int argc, char *argv[] ) +{ + int ret = 1; + int exit_code = MBEDTLS_EXIT_FAILURE; + mbedtls_ecdh_context ctx_cli, ctx_srv; + mbedtls_entropy_context entropy; + mbedtls_ctr_drbg_context ctr_drbg; + unsigned char cli_to_srv[36], srv_to_cli[33]; + const char pers[] = "ecdh"; + + size_t srv_olen; + size_t cli_olen; + unsigned char secret_cli[32] = { 0 }; + unsigned char secret_srv[32] = { 0 }; + const unsigned char *p_cli_to_srv = cli_to_srv; + + ((void) argc); + ((void) argv); + + mbedtls_ecdh_init( &ctx_cli ); + mbedtls_ecdh_init( &ctx_srv ); + mbedtls_ctr_drbg_init( &ctr_drbg ); + + /* + * Initialize random number generation + */ + mbedtls_printf( " . Seed 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, + sizeof pers ) ) != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ctr_drbg_seed returned %d\n", + ret ); + goto exit; + } + + mbedtls_printf( " ok\n" ); + + /* + * Client: initialize context and generate keypair + */ + mbedtls_printf( " . Set up client context, generate EC key pair..." ); + fflush( stdout ); + + ret = mbedtls_ecdh_setup( &ctx_cli, MBEDTLS_ECP_DP_CURVE25519 ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_setup returned %d\n", ret ); + goto exit; + } + + ret = mbedtls_ecdh_make_params( &ctx_cli, &cli_olen, cli_to_srv, + sizeof( cli_to_srv ), + mbedtls_ctr_drbg_random, &ctr_drbg ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_make_params returned %d\n", + ret ); + goto exit; + } + + mbedtls_printf( " ok\n" ); + + /* + * Server: initialize context and generate keypair + */ + mbedtls_printf( " . Server: read params, generate public key..." ); + fflush( stdout ); + + ret = mbedtls_ecdh_read_params( &ctx_srv, &p_cli_to_srv, + p_cli_to_srv + sizeof( cli_to_srv ) ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_read_params returned %d\n", + ret ); + goto exit; + } + + ret = mbedtls_ecdh_make_public( &ctx_srv, &srv_olen, srv_to_cli, + sizeof( srv_to_cli ), + mbedtls_ctr_drbg_random, &ctr_drbg ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_make_public returned %d\n", + ret ); + goto exit; + } + + mbedtls_printf( " ok\n" ); + + /* + * Client: read public key + */ + mbedtls_printf( " . Client: read public key..." ); + fflush( stdout ); + + ret = mbedtls_ecdh_read_public( &ctx_cli, srv_to_cli, + sizeof( srv_to_cli ) ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_read_public returned %d\n", + ret ); + goto exit; + } + + mbedtls_printf( " ok\n" ); + + /* + * Calculate secrets + */ + mbedtls_printf( " . Calculate secrets..." ); + fflush( stdout ); + + ret = mbedtls_ecdh_calc_secret( &ctx_cli, &cli_olen, secret_cli, + sizeof( secret_cli ), + mbedtls_ctr_drbg_random, &ctr_drbg ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_calc_secret returned %d\n", + ret ); + goto exit; + } + + ret = mbedtls_ecdh_calc_secret( &ctx_srv, &srv_olen, secret_srv, + sizeof( secret_srv ), + mbedtls_ctr_drbg_random, &ctr_drbg ); + if( ret != 0 ) + { + mbedtls_printf( " failed\n ! mbedtls_ecdh_calc_secret returned %d\n", + ret ); + goto exit; + } + + mbedtls_printf( " ok\n" ); + + /* + * Verification: are the computed secrets equal? + */ + mbedtls_printf( " . Check if both calculated secrets are equal..." ); + fflush( stdout ); + + ret = memcmp( secret_srv, secret_cli, srv_olen ); + if( ret != 0 || ( cli_olen != srv_olen ) ) + { + mbedtls_printf( " failed\n ! Shared secrets not equal.\n" ); + goto exit; + } + + mbedtls_printf( " ok\n" ); + + exit_code = MBEDTLS_EXIT_SUCCESS; + +exit: + + mbedtls_ecdh_free( &ctx_srv ); + mbedtls_ecdh_free( &ctx_cli ); + mbedtls_ctr_drbg_free( &ctr_drbg ); + mbedtls_entropy_free( &entropy ); + + mbedtls_exit( exit_code ); +} +#endif /* MBEDTLS_ECDH_C && MBEDTLS_ECP_DP_CURVE25519_ENABLED && + MBEDTLS_ENTROPY_C && MBEDTLS_CTR_DRBG_C */ |