diff options
Diffstat (limited to 'third_party/libsrtp/src/crypto/hash/hmac_mbedtls.c')
| -rw-r--r-- | third_party/libsrtp/src/crypto/hash/hmac_mbedtls.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/third_party/libsrtp/src/crypto/hash/hmac_mbedtls.c b/third_party/libsrtp/src/crypto/hash/hmac_mbedtls.c new file mode 100644 index 0000000000..f710be9c78 --- /dev/null +++ b/third_party/libsrtp/src/crypto/hash/hmac_mbedtls.c @@ -0,0 +1,221 @@ +/* + * hmac_mbedtls.c + * + * Implementation of hmac srtp_auth_type_t that leverages Mbedtls + * + * YongCheng Yang + */ +/* + * + * Copyright(c) 2013-2017, Cisco Systems, Inc. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * + * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * + * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * + * Neither the name of the Cisco Systems, Inc. nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS + * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE + * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, + * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES + * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) + * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, + * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) + * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED + * OF THE POSSIBILITY OF SUCH DAMAGE. + * + */ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include "auth.h" +#include "alloc.h" +#include "err.h" /* for srtp_debug */ +#include "auth_test_cases.h" +#include <mbedtls/md.h> + +#define SHA1_DIGEST_SIZE 20 + +/* the debug module for authentiation */ + +srtp_debug_module_t srtp_mod_hmac = { + 0, /* debugging is off by default */ + "hmac sha-1 mbedtls" /* printable name for module */ +}; + +static srtp_err_status_t srtp_hmac_mbedtls_alloc(srtp_auth_t **a, + int key_len, + int out_len) +{ + extern const srtp_auth_type_t srtp_hmac; + + debug_print(srtp_mod_hmac, "allocating auth func with key length %d", + key_len); + debug_print(srtp_mod_hmac, " tag length %d", + out_len); + + /* check output length - should be less than 20 bytes */ + if (key_len > SHA1_DIGEST_SIZE) { + return srtp_err_status_bad_param; + } + /* check output length - should be less than 20 bytes */ + if (out_len > SHA1_DIGEST_SIZE) { + return srtp_err_status_bad_param; + } + + *a = (srtp_auth_t *)srtp_crypto_alloc(sizeof(srtp_auth_t)); + if (*a == NULL) { + return srtp_err_status_alloc_fail; + } + // allocate the buffer of mbedtls context. + (*a)->state = srtp_crypto_alloc(sizeof(mbedtls_md_context_t)); + if ((*a)->state == NULL) { + srtp_crypto_free(*a); + *a = NULL; + return srtp_err_status_alloc_fail; + } + mbedtls_md_init((mbedtls_md_context_t *)(*a)->state); + + /* set pointers */ + (*a)->type = &srtp_hmac; + (*a)->out_len = out_len; + (*a)->key_len = key_len; + (*a)->prefix_len = 0; + + return srtp_err_status_ok; +} + +static srtp_err_status_t srtp_hmac_mbedtls_dealloc(srtp_auth_t *a) +{ + mbedtls_md_context_t *hmac_ctx; + hmac_ctx = (mbedtls_md_context_t *)a->state; + mbedtls_md_free(hmac_ctx); + srtp_crypto_free(hmac_ctx); + /* zeroize entire state*/ + octet_string_set_to_zero(a, sizeof(srtp_auth_t)); + + /* free memory */ + srtp_crypto_free(a); + + return srtp_err_status_ok; +} + +static srtp_err_status_t srtp_hmac_mbedtls_start(void *statev) +{ + mbedtls_md_context_t *state = (mbedtls_md_context_t *)statev; + if (mbedtls_md_hmac_reset(state) != 0) + return srtp_err_status_auth_fail; + + return srtp_err_status_ok; +} + +static srtp_err_status_t srtp_hmac_mbedtls_init(void *statev, + const uint8_t *key, + int key_len) +{ + mbedtls_md_context_t *state = (mbedtls_md_context_t *)statev; + const mbedtls_md_info_t *info = NULL; + + info = mbedtls_md_info_from_type(MBEDTLS_MD_SHA1); + if (info == NULL) + return srtp_err_status_auth_fail; + + if (mbedtls_md_setup(state, info, 1) != 0) + return srtp_err_status_auth_fail; + + debug_print(srtp_mod_hmac, "mbedtls setup, name: %s", + mbedtls_md_get_name(info)); + debug_print(srtp_mod_hmac, "mbedtls setup, size: %d", + mbedtls_md_get_size(info)); + + if (mbedtls_md_hmac_starts(state, key, key_len) != 0) + return srtp_err_status_auth_fail; + + return srtp_err_status_ok; +} + +static srtp_err_status_t srtp_hmac_mbedtls_update(void *statev, + const uint8_t *message, + int msg_octets) +{ + mbedtls_md_context_t *state = (mbedtls_md_context_t *)statev; + + debug_print(srtp_mod_hmac, "input: %s", + srtp_octet_string_hex_string(message, msg_octets)); + + if (mbedtls_md_hmac_update(state, message, msg_octets) != 0) + return srtp_err_status_auth_fail; + + return srtp_err_status_ok; +} + +static srtp_err_status_t srtp_hmac_mbedtls_compute(void *statev, + const uint8_t *message, + int msg_octets, + int tag_len, + uint8_t *result) +{ + mbedtls_md_context_t *state = (mbedtls_md_context_t *)statev; + uint8_t hash_value[SHA1_DIGEST_SIZE]; + int i; + + /* check tag length, return error if we can't provide the value expected */ + if (tag_len > SHA1_DIGEST_SIZE) { + return srtp_err_status_bad_param; + } + + /* hash message, copy output into H */ + if (mbedtls_md_hmac_update(statev, message, msg_octets) != 0) + return srtp_err_status_auth_fail; + + if (mbedtls_md_hmac_finish(state, hash_value) != 0) + return srtp_err_status_auth_fail; + + /* copy hash_value to *result */ + for (i = 0; i < tag_len; i++) { + result[i] = hash_value[i]; + } + + debug_print(srtp_mod_hmac, "output: %s", + srtp_octet_string_hex_string(hash_value, tag_len)); + + return srtp_err_status_ok; +} + +/* end test case 0 */ + +static const char srtp_hmac_mbedtls_description[] = + "hmac sha-1 authentication function using mbedtls"; + +/* + * srtp_auth_type_t hmac is the hmac metaobject + */ + +const srtp_auth_type_t srtp_hmac = { + srtp_hmac_mbedtls_alloc, /* */ + srtp_hmac_mbedtls_dealloc, /* */ + srtp_hmac_mbedtls_init, /* */ + srtp_hmac_mbedtls_compute, /* */ + srtp_hmac_mbedtls_update, /* */ + srtp_hmac_mbedtls_start, /* */ + srtp_hmac_mbedtls_description, /* */ + &srtp_hmac_test_case_0, /* */ + SRTP_HMAC_SHA1 /* */ +}; 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