mirror of
https://github.com/yuzu-emu/mbedtls.git
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ad1115a3fd
byte shifting opertations throughout library/ were only replaced with the byte reading macros when an 0xff mask was being used. The byte reading macros are now more widley used, however they have not been used in all cases of a byte shift operation, as it detracted from the immediate readability or otherwise did not seem appropriate. Signed-off-by: Joe Subbiani <joe.subbiani@arm.com>
720 lines
20 KiB
C
720 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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#include "common.h"
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#if defined(MBEDTLS_DHM_C)
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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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#include <string.h>
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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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#if defined(MBEDTLS_ASN1_PARSE_C)
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#include "mbedtls/asn1.h"
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#endif
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#if defined(MBEDTLS_PLATFORM_C)
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#include "mbedtls/platform.h"
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#else
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#include <stdlib.h>
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#include <stdio.h>
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#define mbedtls_printf printf
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#define mbedtls_calloc calloc
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#define mbedtls_free free
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#endif
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#if !defined(MBEDTLS_DHM_ALT)
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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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* 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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if( end - *p < 2 )
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return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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n = ( (*p)[0] << 8 ) | (*p)[1];
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(*p) += 2;
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if( (int)( end - *p ) < n )
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return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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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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(*p) += n;
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return( 0 );
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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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mbedtls_mpi_init( &U );
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MBEDTLS_MPI_CHK( mbedtls_mpi_sub_int( &U, P, 2 ) );
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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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cleanup:
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mbedtls_mpi_free( &U );
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return( ret );
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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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* 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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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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if( ( ret = dhm_check_range( &ctx->GY, &ctx->P ) ) != 0 )
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return( ret );
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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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* 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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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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cleanup:
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return( ret );
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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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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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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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* 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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if( ( ret = dhm_check_range( &ctx->GX, &ctx->P ) ) != 0 )
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return( ret );
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cleanup:
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return( ret );
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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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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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* 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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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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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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*olen = p - output;
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ctx->len = n1;
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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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* 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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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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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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* 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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if( ilen < 1 || ilen > ctx->len )
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return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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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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return( 0 );
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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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if( olen < 1 || olen > ctx->len )
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return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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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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MBEDTLS_MPI_CHK( mbedtls_mpi_write_binary( &ctx->GX, output, olen ) );
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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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* 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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mbedtls_mpi_init( &R );
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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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return( 0 );
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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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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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return( 0 );
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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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/* 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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/* 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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MBEDTLS_MPI_CHK( mbedtls_mpi_exp_mod( &ctx->Vf, &ctx->Vf, &ctx->X, &ctx->P, &ctx->RP ) );
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cleanup:
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mbedtls_mpi_free( &R );
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return( ret );
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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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if( output_size < ctx->len )
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return( MBEDTLS_ERR_DHM_BAD_INPUT_DATA );
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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 */
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if( f_rng != NULL )
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{
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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 ) );
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/* Unblind secret value */
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if( f_rng != NULL )
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{
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MBEDTLS_MPI_CHK( mbedtls_mpi_mul_mpi( &ctx->K, &ctx->K, &ctx->Vf ) );
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MBEDTLS_MPI_CHK( mbedtls_mpi_mod_mpi( &ctx->K, &ctx->K, &ctx->P ) );
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}
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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 ) );
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cleanup:
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mbedtls_mpi_free( &GYb );
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if( ret != 0 )
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return( MBEDTLS_ERROR_ADD( MBEDTLS_ERR_DHM_CALC_SECRET_FAILED, ret ) );
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return( 0 );
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}
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/*
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* Free the components of a DHM key
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*/
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void mbedtls_dhm_free( mbedtls_dhm_context *ctx )
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{
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if( ctx == NULL )
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return;
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mbedtls_mpi_free( &ctx->pX );
|
|
mbedtls_mpi_free( &ctx->Vf );
|
|
mbedtls_mpi_free( &ctx->Vi );
|
|
mbedtls_mpi_free( &ctx->RP );
|
|
mbedtls_mpi_free( &ctx->K );
|
|
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 */
|