forked from LeenkxTeam/LNXSDK
		
	
		
			
				
	
	
		
			712 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			712 lines
		
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  *  Diffie-Hellman-Merkle key exchange
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|  *
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|  *  Copyright The Mbed TLS Contributors
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|  *  SPDX-License-Identifier: Apache-2.0
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|  *
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|  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
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|  *  not use this file except in compliance with the License.
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|  *  You may obtain a copy of the License at
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|  *
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|  *  http://www.apache.org/licenses/LICENSE-2.0
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|  *
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|  *  Unless required by applicable law or agreed to in writing, software
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|  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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|  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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|  *  See the License for the specific language governing permissions and
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|  *  limitations under the License.
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|  */
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| /*
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|  *  The following sources were referenced in the design of this implementation
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|  *  of the Diffie-Hellman-Merkle algorithm:
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|  *
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|  *  [1] Handbook of Applied Cryptography - 1997, Chapter 12
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|  *      Menezes, van Oorschot and Vanstone
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|  *
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|  */
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| 
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| #include "common.h"
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| 
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| #if defined(MBEDTLS_DHM_C)
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| 
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| #include "mbedtls/dhm.h"
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| #include "mbedtls/platform_util.h"
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| #include "mbedtls/error.h"
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| 
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| #include <string.h>
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| 
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| #if defined(MBEDTLS_PEM_PARSE_C)
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| #include "mbedtls/pem.h"
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| #endif
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| 
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| #if defined(MBEDTLS_ASN1_PARSE_C)
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| #include "mbedtls/asn1.h"
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| #endif
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| 
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| #include "mbedtls/platform.h"
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| 
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| #if !defined(MBEDTLS_DHM_ALT)
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| 
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| #define DHM_VALIDATE_RET( cond )    \
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|     MBEDTLS_INTERNAL_VALIDATE_RET( cond, MBEDTLS_ERR_DHM_BAD_INPUT_DATA )
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| #define DHM_VALIDATE( cond )        \
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|     MBEDTLS_INTERNAL_VALIDATE( cond )
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| 
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| /*
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|  * helper to validate the mbedtls_mpi size and import it
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|  */
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| static int dhm_read_bignum( mbedtls_mpi *X,
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|                             unsigned char **p,
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|                             const unsigned char *end )
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| {
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|     int ret, n;
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| 
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|     if( end - *p < 2 )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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| 
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|     n = ( (*p)[0] << 8 ) | (*p)[1];
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|     (*p) += 2;
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| 
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|     if( (int)( end - *p ) < n )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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| 
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|     if( ( ret = mbedtls_mpi_read_binary( X, *p, n ) ) != 0 )
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|         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_READ_PARAMS_FAILED, ret ) );
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| 
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|     (*p) += n;
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| 
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|     return( 0 );
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| }
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| 
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| /*
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|  * Verify sanity of parameter with regards to P
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|  *
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|  * Parameter should be: 2 <= public_param <= P - 2
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|  *
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|  * This means that we need to return an error if
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|  *              public_param < 2 or public_param > P-2
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|  *
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|  * For more information on the attack, see:
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|  *  http://www.cl.cam.ac.uk/~rja14/Papers/psandqs.pdf
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|  *  http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2005-2643
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|  */
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| static int dhm_check_range( const mbedtls_mpi *param, const mbedtls_mpi *P )
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| {
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|     mbedtls_mpi U;
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|     int ret = 0;
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| 
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|     mbedtls_mpi_init( &U );
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| 
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &U, P, 2 ) );
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| 
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|     if( mbedtls_mpi_cmp_int( param, 2 ) < 0 ||
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|         mbedtls_mpi_cmp_mpi( param, &U ) > 0 )
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|     {
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|         ret = MBEDTLS_ERR_DHM_BAD_INPUT_DATA;
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|     }
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| 
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| cleanup:
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|     mbedtls_mpi_free( &U );
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|     return( ret );
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| }
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| 
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| void mbedtls_dhm_init( mbedtls_dhm_context *ctx )
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| {
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|     DHM_VALIDATE( ctx != NULL );
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|     memset( ctx, 0, sizeof( mbedtls_dhm_context ) );
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| }
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| 
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| /*
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|  * Parse the ServerKeyExchange parameters
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|  */
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| int mbedtls_dhm_read_params( mbedtls_dhm_context *ctx,
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|                      unsigned char **p,
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|                      const unsigned char *end )
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     DHM_VALIDATE_RET( ctx != NULL );
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|     DHM_VALIDATE_RET( p != NULL && *p != NULL );
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|     DHM_VALIDATE_RET( end != NULL );
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| 
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|     if( ( ret = dhm_read_bignum( &ctx->P,  p, end ) ) != 0 ||
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|         ( ret = dhm_read_bignum( &ctx->G,  p, end ) ) != 0 ||
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|         ( ret = dhm_read_bignum( &ctx->GY, p, end ) ) != 0 )
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|         return( ret );
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| 
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|     if( ( ret = dhm_check_range( &ctx->GY, &ctx->P ) ) != 0 )
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|         return( ret );
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| 
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|     ctx->len = mbedtls_mpi_size( &ctx->P );
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| 
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|     return( 0 );
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| }
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| 
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| /*
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|  * Pick a random R in the range [2, M-2] for blinding or key generation.
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|  */
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| static int dhm_random_below( mbedtls_mpi *R, const mbedtls_mpi *M,
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|                 int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
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| {
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|     int ret;
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| 
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_random( R, 3, M, f_rng, p_rng ) );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( R, R, 1 ) );
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| 
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| cleanup:
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|     return( ret );
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| }
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| 
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| static int dhm_make_common( mbedtls_dhm_context *ctx, int x_size,
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|                             int (*f_rng)(void *, unsigned char *, size_t),
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|                             void *p_rng )
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| {
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|     int ret = 0;
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| 
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|     if( mbedtls_mpi_cmp_int( &ctx->P, 0 ) == 0 )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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|     if( x_size < 0 )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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| 
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|     if( (unsigned) x_size < mbedtls_mpi_size( &ctx->P ) )
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|     {
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_fill_random( &ctx->X, x_size, f_rng, p_rng ) );
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|     }
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|     else
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|     {
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|         /* Generate X as large as possible ( <= P - 2 ) */
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|         ret = dhm_random_below( &ctx->X, &ctx->P, f_rng, p_rng );
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|         if( ret == MBEDTLS_ERR_MPI_NOT_ACCEPTABLE )
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|             return( MBEDTLS_ERR_DHM_MAKE_PARAMS_FAILED );
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|         if( ret != 0 )
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|             return( ret );
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|     }
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| 
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|     /*
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|      * Calculate GX = G^X mod P
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|      */
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->GX, &ctx->G, &ctx->X,
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|                           &ctx->P , &ctx->RP ) );
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| 
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|     if( ( ret = dhm_check_range( &ctx->GX, &ctx->P ) ) != 0 )
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|         return( ret );
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| 
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| cleanup:
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|     return( ret );
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| }
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| 
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| /*
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|  * Setup and write the ServerKeyExchange parameters
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|  */
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| int mbedtls_dhm_make_params( mbedtls_dhm_context *ctx, int x_size,
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|                      unsigned char *output, size_t *olen,
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|                      int (*f_rng)(void *, unsigned char *, size_t),
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|                      void *p_rng )
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| {
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|     int ret;
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|     size_t n1, n2, n3;
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|     unsigned char *p;
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|     DHM_VALIDATE_RET( ctx != NULL );
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|     DHM_VALIDATE_RET( output != NULL );
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|     DHM_VALIDATE_RET( olen != NULL );
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|     DHM_VALIDATE_RET( f_rng != NULL );
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| 
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|     ret = dhm_make_common( ctx, x_size, f_rng, p_rng );
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|     if( ret != 0 )
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|         goto cleanup;
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| 
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|     /*
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|      * Export P, G, GX. RFC 5246 §4.4 states that "leading zero octets are
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|      * not required". We omit leading zeros for compactness.
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|      */
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| #define DHM_MPI_EXPORT( X, n )                                          \
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|     do {                                                                \
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( ( X ),               \
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|                                                    p + 2,               \
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|                                                    ( n ) ) );           \
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|         *p++ = MBEDTLS_BYTE_1( n );                                     \
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|         *p++ = MBEDTLS_BYTE_0( n );                                     \
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|         p += ( n );                                                     \
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|     } while( 0 )
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| 
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|     n1 = mbedtls_mpi_size( &ctx->P  );
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|     n2 = mbedtls_mpi_size( &ctx->G  );
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|     n3 = mbedtls_mpi_size( &ctx->GX );
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| 
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|     p = output;
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|     DHM_MPI_EXPORT( &ctx->P , n1 );
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|     DHM_MPI_EXPORT( &ctx->G , n2 );
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|     DHM_MPI_EXPORT( &ctx->GX, n3 );
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| 
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|     *olen = p - output;
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| 
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|     ctx->len = n1;
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| 
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| cleanup:
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|     if( ret != 0 && ret > -128 )
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|         ret = MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_MAKE_PARAMS_FAILED, ret );
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|     return( ret );
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| }
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| 
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| /*
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|  * Set prime modulus and generator
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|  */
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| int mbedtls_dhm_set_group( mbedtls_dhm_context *ctx,
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|                            const mbedtls_mpi *P,
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|                            const mbedtls_mpi *G )
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     DHM_VALIDATE_RET( ctx != NULL );
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|     DHM_VALIDATE_RET( P != NULL );
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|     DHM_VALIDATE_RET( G != NULL );
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| 
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|     if( ( ret = mbedtls_mpi_copy( &ctx->P, P ) ) != 0 ||
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|         ( ret = mbedtls_mpi_copy( &ctx->G, G ) ) != 0 )
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|     {
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|         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_SET_GROUP_FAILED, ret ) );
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|     }
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| 
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|     ctx->len = mbedtls_mpi_size( &ctx->P );
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|     return( 0 );
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| }
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| 
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| /*
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|  * Import the peer's public value G^Y
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|  */
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| int mbedtls_dhm_read_public( mbedtls_dhm_context *ctx,
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|                      const unsigned char *input, size_t ilen )
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     DHM_VALIDATE_RET( ctx != NULL );
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|     DHM_VALIDATE_RET( input != NULL );
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| 
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|     if( ilen < 1 || ilen > ctx->len )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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| 
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|     if( ( ret = mbedtls_mpi_read_binary( &ctx->GY, input, ilen ) ) != 0 )
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|         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_READ_PUBLIC_FAILED, ret ) );
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| 
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|     return( 0 );
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| }
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| 
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| /*
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|  * Create own private value X and export G^X
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|  */
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| int mbedtls_dhm_make_public( mbedtls_dhm_context *ctx, int x_size,
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|                      unsigned char *output, size_t olen,
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|                      int (*f_rng)(void *, unsigned char *, size_t),
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|                      void *p_rng )
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| {
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|     int ret;
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|     DHM_VALIDATE_RET( ctx != NULL );
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|     DHM_VALIDATE_RET( output != NULL );
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|     DHM_VALIDATE_RET( f_rng != NULL );
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| 
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|     if( olen < 1 || olen > ctx->len )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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| 
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|     ret = dhm_make_common( ctx, x_size, f_rng, p_rng );
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|     if( ret == MBEDTLS_ERR_DHM_MAKE_PARAMS_FAILED )
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|         return( MBEDTLS_ERR_DHM_MAKE_PUBLIC_FAILED );
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|     if( ret != 0 )
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|         goto cleanup;
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| 
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->GX, output, olen ) );
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| 
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| cleanup:
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|     if( ret != 0 && ret > -128 )
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|         ret = MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_MAKE_PUBLIC_FAILED, ret );
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|     return( ret );
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| }
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| 
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| 
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| /*
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|  * Use the blinding method and optimisation suggested in section 10 of:
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|  *  KOCHER, Paul C. Timing attacks on implementations of Diffie-Hellman, RSA,
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|  *  DSS, and other systems. In : Advances in Cryptology-CRYPTO'96. Springer
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|  *  Berlin Heidelberg, 1996. p. 104-113.
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|  */
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| static int dhm_update_blinding( mbedtls_dhm_context *ctx,
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|                     int (*f_rng)(void *, unsigned char *, size_t), void *p_rng )
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| {
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|     int ret;
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|     mbedtls_mpi R;
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| 
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|     mbedtls_mpi_init( &R );
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| 
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|     /*
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|      * Don't use any blinding the first time a particular X is used,
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|      * but remember it to use blinding next time.
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|      */
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|     if( mbedtls_mpi_cmp_mpi( &ctx->X, &ctx->pX ) != 0 )
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|     {
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &ctx->pX, &ctx->X ) );
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &ctx->Vi, 1 ) );
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_lset( &ctx->Vf, 1 ) );
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| 
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|         return( 0 );
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|     }
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| 
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|     /*
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|      * Ok, we need blinding. Can we re-use existing values?
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|      * If yes, just update them by squaring them.
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|      */
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|     if( mbedtls_mpi_cmp_int( &ctx->Vi, 1 ) != 0 )
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|     {
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vi, &ctx->Vi, &ctx->Vi ) );
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vi, &ctx->Vi, &ctx->P ) );
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| 
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vf, &ctx->Vf, &ctx->Vf ) );
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->P ) );
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| 
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|         return( 0 );
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|     }
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| 
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|     /*
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|      * We need to generate blinding values from scratch
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|      */
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| 
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|     /* Vi = random( 2, P-2 ) */
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|     MBEDTLS_MPI_CHK( dhm_random_below( &ctx->Vi, &ctx->P, f_rng, p_rng ) );
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| 
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|     /* Vf = Vi^-X mod P
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|      * First compute Vi^-1 = R * (R Vi)^-1, (avoiding leaks from inv_mod),
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|      * then elevate to the Xth power. */
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|     MBEDTLS_MPI_CHK( dhm_random_below( &R, &ctx->P, f_rng, p_rng ) );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vf, &ctx->Vi, &R ) );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->P ) );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_inv_mod( &ctx->Vf, &ctx->Vf, &ctx->P ) );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->Vf, &ctx->Vf, &R ) );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->Vf, &ctx->Vf, &ctx->P ) );
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| 
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->Vf, &ctx->Vf, &ctx->X, &ctx->P, &ctx->RP ) );
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| 
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| cleanup:
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|     mbedtls_mpi_free( &R );
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| 
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|     return( ret );
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| }
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| 
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| /*
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|  * Derive and export the shared secret (G^Y)^X mod P
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|  */
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| int mbedtls_dhm_calc_secret( mbedtls_dhm_context *ctx,
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|                      unsigned char *output, size_t output_size, size_t *olen,
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|                      int (*f_rng)(void *, unsigned char *, size_t),
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|                      void *p_rng )
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| {
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|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
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|     mbedtls_mpi GYb;
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|     DHM_VALIDATE_RET( ctx != NULL );
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|     DHM_VALIDATE_RET( output != NULL );
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|     DHM_VALIDATE_RET( olen != NULL );
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| 
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|     if( output_size < ctx->len )
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|         return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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| 
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|     if( ( ret = dhm_check_range( &ctx->GY, &ctx->P ) ) != 0 )
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|         return( ret );
 | |
| 
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|     mbedtls_mpi_init( &GYb );
 | |
| 
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|     /* Blind peer's value */
 | |
|     if( f_rng != NULL )
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|     {
 | |
|         MBEDTLS_MPI_CHK( dhm_update_blinding( ctx, f_rng, p_rng ) );
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &GYb, &ctx->GY, &ctx->Vi ) );
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &GYb, &GYb, &ctx->P ) );
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|     }
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|     else
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|         MBEDTLS_MPI_CHK( mbedtls_mpi_copy( &GYb, &ctx->GY ) );
 | |
| 
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|     /* Do modular exponentiation */
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->K, &GYb, &ctx->X,
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|                           &ctx->P, &ctx->RP ) );
 | |
| 
 | |
|     /* Unblind secret value */
 | |
|     if( f_rng != NULL )
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|     {
 | |
|         MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->K, &ctx->K, &ctx->Vf ) );
 | |
|         MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->K, &ctx->K, &ctx->P ) );
 | |
|     }
 | |
| 
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|     /* Output the secret without any leading zero byte. This is mandatory
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|      * for TLS per RFC 5246 §8.1.2. */
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|     *olen = mbedtls_mpi_size( &ctx->K );
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|     MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->K, output, *olen ) );
 | |
| 
 | |
| cleanup:
 | |
|     mbedtls_mpi_free( &GYb );
 | |
| 
 | |
|     if( ret != 0 )
 | |
|         return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_CALC_SECRET_FAILED, ret ) );
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Free the components of a DHM key
 | |
|  */
 | |
| void mbedtls_dhm_free( mbedtls_dhm_context *ctx )
 | |
| {
 | |
|     if( ctx == NULL )
 | |
|         return;
 | |
| 
 | |
|     mbedtls_mpi_free( &ctx->pX );
 | |
|     mbedtls_mpi_free( &ctx->Vf );
 | |
|     mbedtls_mpi_free( &ctx->Vi );
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|     mbedtls_mpi_free( &ctx->RP );
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|     mbedtls_mpi_free( &ctx->K  );
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|     mbedtls_mpi_free( &ctx->GY );
 | |
|     mbedtls_mpi_free( &ctx->GX );
 | |
|     mbedtls_mpi_free( &ctx->X  );
 | |
|     mbedtls_mpi_free( &ctx->G  );
 | |
|     mbedtls_mpi_free( &ctx->P  );
 | |
| 
 | |
|     mbedtls_platform_zeroize( ctx, sizeof( mbedtls_dhm_context ) );
 | |
| }
 | |
| 
 | |
| #if defined(MBEDTLS_ASN1_PARSE_C)
 | |
| /*
 | |
|  * Parse DHM parameters
 | |
|  */
 | |
| int mbedtls_dhm_parse_dhm( mbedtls_dhm_context *dhm, const unsigned char *dhmin,
 | |
|                    size_t dhminlen )
 | |
| {
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
|     size_t len;
 | |
|     unsigned char *p, *end;
 | |
| #if defined(MBEDTLS_PEM_PARSE_C)
 | |
|     mbedtls_pem_context pem;
 | |
| #endif /* MBEDTLS_PEM_PARSE_C */
 | |
| 
 | |
|     DHM_VALIDATE_RET( dhm != NULL );
 | |
|     DHM_VALIDATE_RET( dhmin != NULL );
 | |
| 
 | |
| #if defined(MBEDTLS_PEM_PARSE_C)
 | |
|     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_ERROR_ADD( 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_ERROR_ADD( 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_ERROR_ADD( MBEDTLS_ERR_DHM_INVALID_FORMAT, ret );
 | |
|             goto exit;
 | |
|         }
 | |
|         if ( p != end )
 | |
|         {
 | |
|             ret = MBEDTLS_ERROR_ADD( 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 );
 | |
| }
 | |
| 
 | |
| #if defined(MBEDTLS_FS_IO)
 | |
| /*
 | |
|  * Load all data from a file into a given buffer.
 | |
|  *
 | |
|  * The file is expected to contain either PEM or DER encoded data.
 | |
|  * A terminating null byte is always appended. It is included in the announced
 | |
|  * length only if the data looks like it is PEM encoded.
 | |
|  */
 | |
| static int load_file( const char *path, unsigned char **buf, size_t *n )
 | |
| {
 | |
|     FILE *f;
 | |
|     long size;
 | |
| 
 | |
|     if( ( f = fopen( path, "rb" ) ) == NULL )
 | |
|         return( MBEDTLS_ERR_DHM_FILE_IO_ERROR );
 | |
| 
 | |
|     fseek( f, 0, SEEK_END );
 | |
|     if( ( size = ftell( f ) ) == -1 )
 | |
|     {
 | |
|         fclose( f );
 | |
|         return( MBEDTLS_ERR_DHM_FILE_IO_ERROR );
 | |
|     }
 | |
|     fseek( f, 0, SEEK_SET );
 | |
| 
 | |
|     *n = (size_t) size;
 | |
| 
 | |
|     if( *n + 1 == 0 ||
 | |
|         ( *buf = mbedtls_calloc( 1, *n + 1 ) ) == NULL )
 | |
|     {
 | |
|         fclose( f );
 | |
|         return( MBEDTLS_ERR_DHM_ALLOC_FAILED );
 | |
|     }
 | |
| 
 | |
|     if( fread( *buf, 1, *n, f ) != *n )
 | |
|     {
 | |
|         fclose( f );
 | |
| 
 | |
|         mbedtls_platform_zeroize( *buf, *n + 1 );
 | |
|         mbedtls_free( *buf );
 | |
| 
 | |
|         return( MBEDTLS_ERR_DHM_FILE_IO_ERROR );
 | |
|     }
 | |
| 
 | |
|     fclose( f );
 | |
| 
 | |
|     (*buf)[*n] = '\0';
 | |
| 
 | |
|     if( strstr( (const char *) *buf, "-----BEGIN " ) != NULL )
 | |
|         ++*n;
 | |
| 
 | |
|     return( 0 );
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Load and parse DHM parameters
 | |
|  */
 | |
| int mbedtls_dhm_parse_dhmfile( mbedtls_dhm_context *dhm, const char *path )
 | |
| {
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
|     size_t n;
 | |
|     unsigned char *buf;
 | |
|     DHM_VALIDATE_RET( dhm != NULL );
 | |
|     DHM_VALIDATE_RET( path != NULL );
 | |
| 
 | |
|     if( ( ret = load_file( path, &buf, &n ) ) != 0 )
 | |
|         return( ret );
 | |
| 
 | |
|     ret = mbedtls_dhm_parse_dhm( dhm, buf, n );
 | |
| 
 | |
|     mbedtls_platform_zeroize( buf, n );
 | |
|     mbedtls_free( buf );
 | |
| 
 | |
|     return( ret );
 | |
| }
 | |
| #endif /* MBEDTLS_FS_IO */
 | |
| #endif /* MBEDTLS_ASN1_PARSE_C */
 | |
| #endif /* MBEDTLS_DHM_ALT */
 | |
| 
 | |
| #if defined(MBEDTLS_SELF_TEST)
 | |
| 
 | |
| #if defined(MBEDTLS_PEM_PARSE_C)
 | |
| static const char mbedtls_test_dhm_params[] =
 | |
| "-----BEGIN DH PARAMETERS-----\r\n"
 | |
| "MIGHAoGBAJ419DBEOgmQTzo5qXl5fQcN9TN455wkOL7052HzxxRVMyhYmwQcgJvh\r\n"
 | |
| "1sa18fyfR9OiVEMYglOpkqVoGLN7qd5aQNNi5W7/C+VBdHTBJcGZJyyP5B3qcz32\r\n"
 | |
| "9mLJKudlVudV0Qxk5qUJaPZ/xupz0NyoVpviuiBOI1gNi8ovSXWzAgEC\r\n"
 | |
| "-----END DH PARAMETERS-----\r\n";
 | |
| #else /* MBEDTLS_PEM_PARSE_C */
 | |
| static const char mbedtls_test_dhm_params[] = {
 | |
|   0x30, 0x81, 0x87, 0x02, 0x81, 0x81, 0x00, 0x9e, 0x35, 0xf4, 0x30, 0x44,
 | |
|   0x3a, 0x09, 0x90, 0x4f, 0x3a, 0x39, 0xa9, 0x79, 0x79, 0x7d, 0x07, 0x0d,
 | |
|   0xf5, 0x33, 0x78, 0xe7, 0x9c, 0x24, 0x38, 0xbe, 0xf4, 0xe7, 0x61, 0xf3,
 | |
|   0xc7, 0x14, 0x55, 0x33, 0x28, 0x58, 0x9b, 0x04, 0x1c, 0x80, 0x9b, 0xe1,
 | |
|   0xd6, 0xc6, 0xb5, 0xf1, 0xfc, 0x9f, 0x47, 0xd3, 0xa2, 0x54, 0x43, 0x18,
 | |
|   0x82, 0x53, 0xa9, 0x92, 0xa5, 0x68, 0x18, 0xb3, 0x7b, 0xa9, 0xde, 0x5a,
 | |
|   0x40, 0xd3, 0x62, 0xe5, 0x6e, 0xff, 0x0b, 0xe5, 0x41, 0x74, 0x74, 0xc1,
 | |
|   0x25, 0xc1, 0x99, 0x27, 0x2c, 0x8f, 0xe4, 0x1d, 0xea, 0x73, 0x3d, 0xf6,
 | |
|   0xf6, 0x62, 0xc9, 0x2a, 0xe7, 0x65, 0x56, 0xe7, 0x55, 0xd1, 0x0c, 0x64,
 | |
|   0xe6, 0xa5, 0x09, 0x68, 0xf6, 0x7f, 0xc6, 0xea, 0x73, 0xd0, 0xdc, 0xa8,
 | |
|   0x56, 0x9b, 0xe2, 0xba, 0x20, 0x4e, 0x23, 0x58, 0x0d, 0x8b, 0xca, 0x2f,
 | |
|   0x49, 0x75, 0xb3, 0x02, 0x01, 0x02 };
 | |
| #endif /* MBEDTLS_PEM_PARSE_C */
 | |
| 
 | |
| static const size_t mbedtls_test_dhm_params_len = sizeof( mbedtls_test_dhm_params );
 | |
| 
 | |
| /*
 | |
|  * Checkup routine
 | |
|  */
 | |
| int mbedtls_dhm_self_test( int verbose )
 | |
| {
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
|     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 );
 | |
| }
 | |
| 
 | |
| #endif /* MBEDTLS_SELF_TEST */
 | |
| 
 | |
| #endif /* MBEDTLS_DHM_C */
 |