| Index: libsrtp/crypto/hash/hmac.c
|
| ===================================================================
|
| --- libsrtp/crypto/hash/hmac.c (revision 0)
|
| +++ libsrtp/crypto/hash/hmac.c (revision 0)
|
| @@ -0,0 +1,268 @@
|
| +/*
|
| + * hmac.c
|
| + *
|
| + * implementation of hmac auth_type_t
|
| + *
|
| + * David A. McGrew
|
| + * Cisco Systems, Inc.
|
| + */
|
| +/*
|
| + *
|
| + * Copyright(c) 2001-2006 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.
|
| + *
|
| + */
|
| +
|
| +#include "hmac.h"
|
| +#include "alloc.h"
|
| +
|
| +/* the debug module for authentiation */
|
| +
|
| +debug_module_t mod_hmac = {
|
| + 0, /* debugging is off by default */
|
| + "hmac sha-1" /* printable name for module */
|
| +};
|
| +
|
| +
|
| +err_status_t
|
| +hmac_alloc(auth_t **a, int key_len, int out_len) {
|
| + extern auth_type_t hmac;
|
| + uint8_t *pointer;
|
| +
|
| + debug_print(mod_hmac, "allocating auth func with key length %d", key_len);
|
| + debug_print(mod_hmac, " tag length %d", out_len);
|
| +
|
| + /*
|
| + * check key length - note that we don't support keys larger
|
| + * than 20 bytes yet
|
| + */
|
| + if (key_len > 20)
|
| + return err_status_bad_param;
|
| +
|
| + /* check output length - should be less than 20 bytes */
|
| + if (out_len > 20)
|
| + return err_status_bad_param;
|
| +
|
| + /* allocate memory for auth and hmac_ctx_t structures */
|
| + pointer = (uint8_t*)crypto_alloc(sizeof(hmac_ctx_t) + sizeof(auth_t));
|
| + if (pointer == NULL)
|
| + return err_status_alloc_fail;
|
| +
|
| + /* set pointers */
|
| + *a = (auth_t *)pointer;
|
| + (*a)->type = &hmac;
|
| + (*a)->state = pointer + sizeof(auth_t);
|
| + (*a)->out_len = out_len;
|
| + (*a)->key_len = key_len;
|
| + (*a)->prefix_len = 0;
|
| +
|
| + /* increment global count of all hmac uses */
|
| + hmac.ref_count++;
|
| +
|
| + return err_status_ok;
|
| +}
|
| +
|
| +err_status_t
|
| +hmac_dealloc(auth_t *a) {
|
| + extern auth_type_t hmac;
|
| +
|
| + /* zeroize entire state*/
|
| + octet_string_set_to_zero((uint8_t *)a,
|
| + sizeof(hmac_ctx_t) + sizeof(auth_t));
|
| +
|
| + /* free memory */
|
| + crypto_free(a);
|
| +
|
| + /* decrement global count of all hmac uses */
|
| + hmac.ref_count--;
|
| +
|
| + return err_status_ok;
|
| +}
|
| +
|
| +err_status_t
|
| +hmac_init(hmac_ctx_t *state, const uint8_t *key, int key_len) {
|
| + int i;
|
| + uint8_t ipad[64];
|
| +
|
| + /*
|
| + * check key length - note that we don't support keys larger
|
| + * than 20 bytes yet
|
| + */
|
| + if (key_len > 20)
|
| + return err_status_bad_param;
|
| +
|
| + /*
|
| + * set values of ipad and opad by exoring the key into the
|
| + * appropriate constant values
|
| + */
|
| + for (i=0; i < key_len; i++) {
|
| + ipad[i] = key[i] ^ 0x36;
|
| + state->opad[i] = key[i] ^ 0x5c;
|
| + }
|
| + /* set the rest of ipad, opad to constant values */
|
| + for ( ; i < 64; i++) {
|
| + ipad[i] = 0x36;
|
| + ((uint8_t *)state->opad)[i] = 0x5c;
|
| + }
|
| +
|
| + debug_print(mod_hmac, "ipad: %s", octet_string_hex_string(ipad, 64));
|
| +
|
| + /* initialize sha1 context */
|
| + sha1_init(&state->init_ctx);
|
| +
|
| + /* hash ipad ^ key */
|
| + sha1_update(&state->init_ctx, ipad, 64);
|
| + memcpy(&state->ctx, &state->init_ctx, sizeof(sha1_ctx_t));
|
| +
|
| + return err_status_ok;
|
| +}
|
| +
|
| +err_status_t
|
| +hmac_start(hmac_ctx_t *state) {
|
| +
|
| + memcpy(&state->ctx, &state->init_ctx, sizeof(sha1_ctx_t));
|
| +
|
| + return err_status_ok;
|
| +}
|
| +
|
| +err_status_t
|
| +hmac_update(hmac_ctx_t *state, const uint8_t *message, int msg_octets) {
|
| +
|
| + debug_print(mod_hmac, "input: %s",
|
| + octet_string_hex_string(message, msg_octets));
|
| +
|
| + /* hash message into sha1 context */
|
| + sha1_update(&state->ctx, message, msg_octets);
|
| +
|
| + return err_status_ok;
|
| +}
|
| +
|
| +err_status_t
|
| +hmac_compute(hmac_ctx_t *state, const void *message,
|
| + int msg_octets, int tag_len, uint8_t *result) {
|
| + uint32_t hash_value[5];
|
| + uint32_t H[5];
|
| + int i;
|
| +
|
| + /* check tag length, return error if we can't provide the value expected */
|
| + if (tag_len > 20)
|
| + return err_status_bad_param;
|
| +
|
| + /* hash message, copy output into H */
|
| + hmac_update(state, (const uint8_t*)message, msg_octets);
|
| + sha1_final(&state->ctx, H);
|
| +
|
| + /*
|
| + * note that we don't need to debug_print() the input, since the
|
| + * function hmac_update() already did that for us
|
| + */
|
| + debug_print(mod_hmac, "intermediate state: %s",
|
| + octet_string_hex_string((uint8_t *)H, 20));
|
| +
|
| + /* re-initialize hash context */
|
| + sha1_init(&state->ctx);
|
| +
|
| + /* hash opad ^ key */
|
| + sha1_update(&state->ctx, (uint8_t *)state->opad, 64);
|
| +
|
| + /* hash the result of the inner hash */
|
| + sha1_update(&state->ctx, (uint8_t *)H, 20);
|
| +
|
| + /* the result is returned in the array hash_value[] */
|
| + sha1_final(&state->ctx, hash_value);
|
| +
|
| + /* copy hash_value to *result */
|
| + for (i=0; i < tag_len; i++)
|
| + result[i] = ((uint8_t *)hash_value)[i];
|
| +
|
| + debug_print(mod_hmac, "output: %s",
|
| + octet_string_hex_string((uint8_t *)hash_value, tag_len));
|
| +
|
| + return err_status_ok;
|
| +}
|
| +
|
| +
|
| +/* begin test case 0 */
|
| +
|
| +uint8_t
|
| +hmac_test_case_0_key[20] = {
|
| + 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
|
| + 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b, 0x0b,
|
| + 0x0b, 0x0b, 0x0b, 0x0b
|
| +};
|
| +
|
| +uint8_t
|
| +hmac_test_case_0_data[8] = {
|
| + 0x48, 0x69, 0x20, 0x54, 0x68, 0x65, 0x72, 0x65 /* "Hi There" */
|
| +};
|
| +
|
| +uint8_t
|
| +hmac_test_case_0_tag[20] = {
|
| + 0xb6, 0x17, 0x31, 0x86, 0x55, 0x05, 0x72, 0x64,
|
| + 0xe2, 0x8b, 0xc0, 0xb6, 0xfb, 0x37, 0x8c, 0x8e,
|
| + 0xf1, 0x46, 0xbe, 0x00
|
| +};
|
| +
|
| +auth_test_case_t
|
| +hmac_test_case_0 = {
|
| + 20, /* octets in key */
|
| + hmac_test_case_0_key, /* key */
|
| + 8, /* octets in data */
|
| + hmac_test_case_0_data, /* data */
|
| + 20, /* octets in tag */
|
| + hmac_test_case_0_tag, /* tag */
|
| + NULL /* pointer to next testcase */
|
| +};
|
| +
|
| +/* end test case 0 */
|
| +
|
| +char hmac_description[] = "hmac sha-1 authentication function";
|
| +
|
| +/*
|
| + * auth_type_t hmac is the hmac metaobject
|
| + */
|
| +
|
| +auth_type_t
|
| +hmac = {
|
| + (auth_alloc_func) hmac_alloc,
|
| + (auth_dealloc_func) hmac_dealloc,
|
| + (auth_init_func) hmac_init,
|
| + (auth_compute_func) hmac_compute,
|
| + (auth_update_func) hmac_update,
|
| + (auth_start_func) hmac_start,
|
| + (char *) hmac_description,
|
| + (int) 0, /* instance count */
|
| + (auth_test_case_t *) &hmac_test_case_0,
|
| + (debug_module_t *) &mod_hmac,
|
| + (auth_type_id_t) HMAC_SHA1
|
| +};
|
| +
|
|
|
| Property changes on: libsrtp/crypto/hash/hmac.c
|
| ___________________________________________________________________
|
| Added: svn:eol-style
|
| + LF
|
|
|
|
|