/* * Checkup routine */ int mbedtls_dhm_self_test( int verbose ) { int ret; mbedtls_dhm_context dhm; mbedtls_dhm_init( &dhm ); if( verbose != 0 ) mbedtls_printf( " DHM parameter load: " ); if( ( ret = mbedtls_dhm_parse_dhm( &dhm, (const unsigned char *) mbedtls_test_dhm_params, mbedtls_test_dhm_params_len ) ) != 0 ) { if( verbose != 0 ) mbedtls_printf( "failed\n" ); ret = 1; goto exit; } if( verbose != 0 ) mbedtls_printf( "passed\n\n" ); exit: mbedtls_dhm_free( &dhm ); return( ret ); }
void blufi_security_deinit(void) { mbedtls_dhm_free(&blufi_sec->dhm); mbedtls_aes_free(&blufi_sec->aes); memset(blufi_sec, 0x0, sizeof(struct blufi_security)); free(blufi_sec); blufi_sec = NULL; }
/* * Parse DHM parameters */ int mbedtls_dhm_parse_dhm( mbedtls_dhm_context *dhm, const unsigned char *dhmin, size_t dhminlen ) { int ret; size_t len; unsigned char *p, *end; #if defined(MBEDTLS_PEM_PARSE_C) mbedtls_pem_context pem; mbedtls_pem_init( &pem ); /* Avoid calling mbedtls_pem_read_buffer() on non-null-terminated string */ if( dhminlen == 0 || dhmin[dhminlen - 1] != '\0' ) ret = MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT; else ret = mbedtls_pem_read_buffer( &pem, "-----BEGIN DH PARAMETERS-----", "-----END DH PARAMETERS-----", dhmin, NULL, 0, &dhminlen ); if( ret == 0 ) { /* * Was PEM encoded */ dhminlen = pem.buflen; } else if( ret != MBEDTLS_ERR_PEM_NO_HEADER_FOOTER_PRESENT ) goto exit; p = ( ret == 0 ) ? pem.buf : (unsigned char *) dhmin; #else p = (unsigned char *) dhmin; #endif /* MBEDTLS_PEM_PARSE_C */ end = p + dhminlen; /* * DHParams ::= SEQUENCE { * prime INTEGER, -- P * generator INTEGER, -- g * privateValueLength INTEGER OPTIONAL * } */ if( ( ret = mbedtls_asn1_get_tag( &p, end, &len, MBEDTLS_ASN1_CONSTRUCTED | MBEDTLS_ASN1_SEQUENCE ) ) != 0 ) { ret = MBEDTLS_ERR_DHM_INVALID_FORMAT + ret; goto exit; } end = p + len; if( ( ret = mbedtls_asn1_get_mpi( &p, end, &dhm->P ) ) != 0 || ( ret = mbedtls_asn1_get_mpi( &p, end, &dhm->G ) ) != 0 ) { ret = MBEDTLS_ERR_DHM_INVALID_FORMAT + ret; goto exit; } if( p != end ) { /* This might be the optional privateValueLength. * If so, we can cleanly discard it */ mbedtls_mpi rec; mbedtls_mpi_init( &rec ); ret = mbedtls_asn1_get_mpi( &p, end, &rec ); mbedtls_mpi_free( &rec ); if ( ret != 0 ) { ret = MBEDTLS_ERR_DHM_INVALID_FORMAT + ret; goto exit; } if ( p != end ) { ret = MBEDTLS_ERR_DHM_INVALID_FORMAT + MBEDTLS_ERR_ASN1_LENGTH_MISMATCH; goto exit; } } ret = 0; dhm->len = mbedtls_mpi_size( &dhm->P ); exit: #if defined(MBEDTLS_PEM_PARSE_C) mbedtls_pem_free( &pem ); #endif if( ret != 0 ) mbedtls_dhm_free( dhm ); return( ret ); }
int main( void ) { FILE *f; int ret; size_t n, buflen; mbedtls_net_context server_fd; unsigned char *p, *end; unsigned char buf[2048]; unsigned char hash[32]; const char *pers = "dh_client"; mbedtls_entropy_context entropy; mbedtls_ctr_drbg_context ctr_drbg; mbedtls_rsa_context rsa; mbedtls_dhm_context dhm; mbedtls_aes_context aes; mbedtls_net_init( &server_fd ); mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, MBEDTLS_MD_SHA256 ); mbedtls_dhm_init( &dhm ); mbedtls_aes_init( &aes ); mbedtls_ctr_drbg_init( &ctr_drbg ); /* * 1. Setup the RNG */ 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; } /* * 2. Read the server's public RSA key */ mbedtls_printf( "\n . Reading public key from rsa_pub.txt" ); fflush( stdout ); if( ( f = fopen( "rsa_pub.txt", "rb" ) ) == NULL ) { ret = 1; mbedtls_printf( " failed\n ! Could not open rsa_pub.txt\n" \ " ! Please run rsa_genkey first\n\n" ); goto exit; } mbedtls_rsa_init( &rsa, MBEDTLS_RSA_PKCS_V15, 0 ); if( ( ret = mbedtls_mpi_read_file( &rsa.N, 16, f ) ) != 0 || ( ret = mbedtls_mpi_read_file( &rsa.E, 16, f ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_mpi_read_file returned %d\n\n", ret ); goto exit; } rsa.len = ( mbedtls_mpi_bitlen( &rsa.N ) + 7 ) >> 3; fclose( f ); /* * 3. Initiate the connection */ mbedtls_printf( "\n . Connecting to tcp/%s/%s", SERVER_NAME, SERVER_PORT ); fflush( stdout ); if( ( ret = mbedtls_net_connect( &server_fd, SERVER_NAME, SERVER_PORT, MBEDTLS_NET_PROTO_TCP ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_net_connect returned %d\n\n", ret ); goto exit; } /* * 4a. First get the buffer length */ mbedtls_printf( "\n . Receiving the server's DH parameters" ); fflush( stdout ); memset( buf, 0, sizeof( buf ) ); if( ( ret = mbedtls_net_recv( &server_fd, buf, 2 ) ) != 2 ) { mbedtls_printf( " failed\n ! mbedtls_net_recv returned %d\n\n", ret ); goto exit; } n = buflen = ( buf[0] << 8 ) | buf[1]; if( buflen < 1 || buflen > sizeof( buf ) ) { mbedtls_printf( " failed\n ! Got an invalid buffer length\n\n" ); goto exit; } /* * 4b. Get the DHM parameters: P, G and Ys = G^Xs mod P */ memset( buf, 0, sizeof( buf ) ); if( ( ret = mbedtls_net_recv( &server_fd, buf, n ) ) != (int) n ) { mbedtls_printf( " failed\n ! mbedtls_net_recv returned %d\n\n", ret ); goto exit; } p = buf, end = buf + buflen; if( ( ret = mbedtls_dhm_read_params( &dhm, &p, end ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_dhm_read_params returned %d\n\n", ret ); goto exit; } if( dhm.len < 64 || dhm.len > 512 ) { ret = 1; mbedtls_printf( " failed\n ! Invalid DHM modulus size\n\n" ); goto exit; } /* * 5. Check that the server's RSA signature matches * the SHA-256 hash of (P,G,Ys) */ mbedtls_printf( "\n . Verifying the server's RSA signature" ); fflush( stdout ); p += 2; if( ( n = (size_t) ( end - p ) ) != rsa.len ) { ret = 1; mbedtls_printf( " failed\n ! Invalid RSA signature size\n\n" ); goto exit; } mbedtls_sha1( buf, (int)( p - 2 - buf ), hash ); if( ( ret = mbedtls_rsa_pkcs1_verify( &rsa, NULL, NULL, MBEDTLS_RSA_PUBLIC, MBEDTLS_MD_SHA256, 0, hash, p ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_rsa_pkcs1_verify returned %d\n\n", ret ); goto exit; } /* * 6. Send our public value: Yc = G ^ Xc mod P */ mbedtls_printf( "\n . Sending own public value to server" ); fflush( stdout ); n = dhm.len; if( ( ret = mbedtls_dhm_make_public( &dhm, (int) dhm.len, buf, n, mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_dhm_make_public returned %d\n\n", ret ); goto exit; } if( ( ret = mbedtls_net_send( &server_fd, buf, n ) ) != (int) n ) { mbedtls_printf( " failed\n ! mbedtls_net_send returned %d\n\n", ret ); goto exit; } /* * 7. Derive the shared secret: K = Ys ^ Xc mod P */ mbedtls_printf( "\n . Shared secret: " ); fflush( stdout ); if( ( ret = mbedtls_dhm_calc_secret( &dhm, buf, sizeof( buf ), &n, mbedtls_ctr_drbg_random, &ctr_drbg ) ) != 0 ) { mbedtls_printf( " failed\n ! mbedtls_dhm_calc_secret returned %d\n\n", ret ); goto exit; } for( n = 0; n < 16; n++ ) mbedtls_printf( "%02x", buf[n] ); /* * 8. Setup the AES-256 decryption key * * This is an overly simplified example; best practice is * to hash the shared secret with a random value to derive * the keying material for the encryption/decryption keys, * IVs and MACs. */ mbedtls_printf( "...\n . Receiving and decrypting the ciphertext" ); fflush( stdout ); mbedtls_aes_setkey_dec( &aes, buf, 256 ); memset( buf, 0, sizeof( buf ) ); if( ( ret = mbedtls_net_recv( &server_fd, buf, 16 ) ) != 16 ) { mbedtls_printf( " failed\n ! mbedtls_net_recv returned %d\n\n", ret ); goto exit; } mbedtls_aes_crypt_ecb( &aes, MBEDTLS_AES_DECRYPT, buf, buf ); buf[16] = '\0'; mbedtls_printf( "\n . Plaintext is \"%s\"\n\n", (char *) buf ); exit: mbedtls_net_free( &server_fd ); mbedtls_aes_free( &aes ); mbedtls_rsa_free( &rsa ); mbedtls_dhm_free( &dhm ); mbedtls_ctr_drbg_free( &ctr_drbg ); mbedtls_entropy_free( &entropy ); #if defined(_WIN32) mbedtls_printf( " + Press Enter to exit this program.\n" ); fflush( stdout ); getchar(); #endif return( ret ); }
void DHMContext::destructor(State & state, mbedtls_dhm_context * context){ mbedtls_dhm_free(context); delete context; }