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			698 lines
		
	
	
	
		
			20 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			698 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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| #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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| 
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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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|     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_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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|     mbedtls_mpi L, U;
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|     int ret = 0;
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| 
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|     mbedtls_mpi_init(&L);
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|     mbedtls_mpi_init(&U);
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| 
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|     MBEDTLS_MPI_CHK(mbedtls_mpi_lset(&L, 2));
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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_mpi(param, &L) < 0 ||
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|             mbedtls_mpi_cmp_mpi(param, &U) > 0) {
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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(&L);
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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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|     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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|     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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|  * 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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|     int ret, count = 0;
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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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|     if (mbedtls_mpi_cmp_int(&ctx->P, 0) == 0)
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|         return (MBEDTLS_ERR_DHM_BAD_INPUT_DATA);
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| 
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|     /*
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|      * Generate X as large as possible ( < P )
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|      */
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|     do {
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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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|         while (mbedtls_mpi_cmp_mpi(&ctx->X, &ctx->P) >= 0)
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|             MBEDTLS_MPI_CHK(mbedtls_mpi_shift_r(&ctx->X, 1));
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| 
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|         if (count++ > 10)
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|             return (MBEDTLS_ERR_DHM_MAKE_PARAMS_FAILED);
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|     } while (dhm_check_range(&ctx->X, &ctx->P) != 0);
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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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|     /*
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|      * export P, G, GX
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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++ = (unsigned char)( ( n ) >> 8 );                           \
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|         *p++ = (unsigned char)( ( 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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| 
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|     if (ret != 0)
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|         return (MBEDTLS_ERR_DHM_MAKE_PARAMS_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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|  * 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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|     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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|         return (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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|     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_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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|     int ret, count = 0;
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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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|     if (mbedtls_mpi_cmp_int(&ctx->P, 0) == 0)
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|         return (MBEDTLS_ERR_DHM_BAD_INPUT_DATA);
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| 
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|     /*
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|      * generate X and calculate GX = G^X mod P
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|      */
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|     do {
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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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|         while (mbedtls_mpi_cmp_mpi(&ctx->X, &ctx->P) >= 0)
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|             MBEDTLS_MPI_CHK(mbedtls_mpi_shift_r(&ctx->X, 1));
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| 
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|         if (count++ > 10)
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|             return (MBEDTLS_ERR_DHM_MAKE_PUBLIC_FAILED);
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|     } while (dhm_check_range(&ctx->X, &ctx->P) != 0);
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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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|     MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&ctx->GX, output, olen));
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| 
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| cleanup:
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| 
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|     if (ret != 0)
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|         return (MBEDTLS_ERR_DHM_MAKE_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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|  * Pick a random R in the range [2, M) for blinding purposes
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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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|     int ret, count;
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| 
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|     count = 0;
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|     do {
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|         MBEDTLS_MPI_CHK(mbedtls_mpi_fill_random(R, mbedtls_mpi_size(M), f_rng, p_rng));
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| 
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|         while (mbedtls_mpi_cmp_mpi(R, M) >= 0)
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|             MBEDTLS_MPI_CHK(mbedtls_mpi_shift_r(R, 1));
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| 
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|         if (count++ > 10)
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|             return (MBEDTLS_ERR_MPI_NOT_ACCEPTABLE);
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|     } while (mbedtls_mpi_cmp_int(R, 1) <= 0);
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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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| /*
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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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|     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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|         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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|         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-1 ) */
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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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| 
 | |
| cleanup:
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|     mbedtls_mpi_free(&R);
 | |
| 
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|     return (ret);
 | |
| }
 | |
| 
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| /*
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|  * Derive and export the shared secret (G^Y)^X mod P
 | |
|  */
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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,
 | |
|                             int (*f_rng)(void *, unsigned char *, size_t),
 | |
|                             void *p_rng) {
 | |
|     int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
 | |
|     mbedtls_mpi GYb;
 | |
|     DHM_VALIDATE_RET(ctx != NULL);
 | |
|     DHM_VALIDATE_RET(output != NULL);
 | |
|     DHM_VALIDATE_RET(olen != NULL);
 | |
| 
 | |
|     if (output_size < ctx->len)
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|         return (MBEDTLS_ERR_DHM_BAD_INPUT_DATA);
 | |
| 
 | |
|     if ((ret = dhm_check_range(&ctx->GY, &ctx->P)) != 0)
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|         return (ret);
 | |
| 
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|     mbedtls_mpi_init(&GYb);
 | |
| 
 | |
|     /* 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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|     } else
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|         MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&GYb, &ctx->GY));
 | |
| 
 | |
|     /* Do modular exponentiation */
 | |
|     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));
 | |
|     }
 | |
| 
 | |
|     *olen = mbedtls_mpi_size(&ctx->K);
 | |
| 
 | |
|     MBEDTLS_MPI_CHK(mbedtls_mpi_write_binary(&ctx->K, output, *olen));
 | |
| 
 | |
| cleanup:
 | |
|     mbedtls_mpi_free(&GYb);
 | |
| 
 | |
|     if (ret != 0)
 | |
|         return (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);
 | |
|     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_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);
 | |
| }
 | |
| 
 | |
| #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 */
 |