mirror of
https://github.com/Relintai/pandemonium_engine_minimal.git
synced 2024-11-10 20:12:10 +01:00
724 lines
20 KiB
C
724 lines
20 KiB
C
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/*
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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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#include "mbedtls/platform.h"
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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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}
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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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}
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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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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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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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}
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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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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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}
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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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MBEDTLS_MPI_CHK(mbedtls_mpi_fill_random(&ctx->X, x_size, f_rng, p_rng));
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} else {
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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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}
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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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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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* 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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/*
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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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}
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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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|
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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_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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/*
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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) {
|
||
|
return MBEDTLS_ERROR_ADD(MBEDTLS_ERR_DHM_READ_PUBLIC_FAILED, ret);
|
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|
}
|
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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),
|
||
|
void *p_rng)
|
||
|
{
|
||
|
int ret;
|
||
|
DHM_VALIDATE_RET(ctx != NULL);
|
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|
DHM_VALIDATE_RET(output != NULL);
|
||
|
DHM_VALIDATE_RET(f_rng != NULL);
|
||
|
|
||
|
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));
|
||
|
|
||
|
cleanup:
|
||
|
if (ret != 0 && ret > -128) {
|
||
|
ret = MBEDTLS_ERROR_ADD(MBEDTLS_ERR_DHM_MAKE_PUBLIC_FAILED, ret);
|
||
|
}
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
|
||
|
/*
|
||
|
* Use the blinding method and optimisation suggested in section 10 of:
|
||
|
* KOCHER, Paul C. Timing attacks on implementations of Diffie-Hellman, RSA,
|
||
|
* DSS, and other systems. In : Advances in Cryptology-CRYPTO'96. Springer
|
||
|
* Berlin Heidelberg, 1996. p. 104-113.
|
||
|
*/
|
||
|
static int dhm_update_blinding(mbedtls_dhm_context *ctx,
|
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|
int (*f_rng)(void *, unsigned char *, size_t), void *p_rng)
|
||
|
{
|
||
|
int ret;
|
||
|
mbedtls_mpi R;
|
||
|
|
||
|
mbedtls_mpi_init(&R);
|
||
|
|
||
|
/*
|
||
|
* Don't use any blinding the first time a particular X is used,
|
||
|
* but remember it to use blinding next time.
|
||
|
*/
|
||
|
if (mbedtls_mpi_cmp_mpi(&ctx->X, &ctx->pX) != 0) {
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&ctx->pX, &ctx->X));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_lset(&ctx->Vi, 1));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_lset(&ctx->Vf, 1));
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Ok, we need blinding. Can we re-use existing values?
|
||
|
* If yes, just update them by squaring them.
|
||
|
*/
|
||
|
if (mbedtls_mpi_cmp_int(&ctx->Vi, 1) != 0) {
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&ctx->Vi, &ctx->Vi, &ctx->Vi));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&ctx->Vi, &ctx->Vi, &ctx->P));
|
||
|
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&ctx->Vf, &ctx->Vf, &ctx->Vf));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&ctx->Vf, &ctx->Vf, &ctx->P));
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* We need to generate blinding values from scratch
|
||
|
*/
|
||
|
|
||
|
/* Vi = random( 2, P-2 ) */
|
||
|
MBEDTLS_MPI_CHK(dhm_random_below(&ctx->Vi, &ctx->P, f_rng, p_rng));
|
||
|
|
||
|
/* Vf = Vi^-X mod P
|
||
|
* First compute Vi^-1 = R * (R Vi)^-1, (avoiding leaks from inv_mod),
|
||
|
* then elevate to the Xth power. */
|
||
|
MBEDTLS_MPI_CHK(dhm_random_below(&R, &ctx->P, f_rng, p_rng));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&ctx->Vf, &ctx->Vi, &R));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&ctx->Vf, &ctx->Vf, &ctx->P));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_inv_mod(&ctx->Vf, &ctx->Vf, &ctx->P));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&ctx->Vf, &ctx->Vf, &R));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&ctx->Vf, &ctx->Vf, &ctx->P));
|
||
|
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&ctx->Vf, &ctx->Vf, &ctx->X, &ctx->P, &ctx->RP));
|
||
|
|
||
|
cleanup:
|
||
|
mbedtls_mpi_free(&R);
|
||
|
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Derive and export the shared secret (G^Y)^X mod P
|
||
|
*/
|
||
|
int mbedtls_dhm_calc_secret(mbedtls_dhm_context *ctx,
|
||
|
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) {
|
||
|
return MBEDTLS_ERR_DHM_BAD_INPUT_DATA;
|
||
|
}
|
||
|
|
||
|
if ((ret = dhm_check_range(&ctx->GY, &ctx->P)) != 0) {
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
mbedtls_mpi_init(&GYb);
|
||
|
|
||
|
/* Blind peer's value */
|
||
|
if (f_rng != NULL) {
|
||
|
MBEDTLS_MPI_CHK(dhm_update_blinding(ctx, f_rng, p_rng));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mul_mpi(&GYb, &ctx->GY, &ctx->Vi));
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_mod_mpi(&GYb, &GYb, &ctx->P));
|
||
|
} else {
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_copy(&GYb, &ctx->GY));
|
||
|
}
|
||
|
|
||
|
/* Do modular exponentiation */
|
||
|
MBEDTLS_MPI_CHK(mbedtls_mpi_exp_mod(&ctx->K, &GYb, &ctx->X,
|
||
|
&ctx->P, &ctx->RP));
|
||
|
|
||
|
/* Unblind secret value */
|
||
|
if (f_rng != NULL) {
|
||
|
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));
|
||
|
}
|
||
|
|
||
|
/* Output the secret without any leading zero byte. This is mandatory
|
||
|
* for TLS per RFC 5246 §8.1.2. */
|
||
|
*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_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);
|
||
|
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 */
|