/*
* Copyright (C) 2012 Martin Storsjo
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <string.h>
#include "attributes.h"
#include "hmac.h"
#include "md5.h"
#include "sha.h"
#include "sha512.h"
#include "mem.h"
#define MAX_HASHLEN 64
#define MAX_BLOCKLEN 128
struct AVHMAC {
void *hash;
int blocklen, hashlen;
void (*final)(void*, uint8_t*);
void (*update)(void*, const uint8_t*, int len);
void (*init)(void*);
uint8_t key[MAX_BLOCKLEN];
int keylen;
};
#define DEFINE_SHA(bits) \
static av_cold void sha ## bits ##_init(void *ctx) \
{ \
av_sha_init(ctx, bits); \
}
#define DEFINE_SHA512(bits) \
static av_cold void sha ## bits ##_init(void *ctx) \
{ \
av_sha512_init(ctx, bits); \
}
DEFINE_SHA(160)
DEFINE_SHA(224)
DEFINE_SHA(256)
DEFINE_SHA512(384)
DEFINE_SHA512(512)
AVHMAC *av_hmac_alloc(enum AVHMACType type)
{
AVHMAC *c = av_mallocz(sizeof(*c));
if (!c)
return NULL;
switch (type) {
case AV_HMAC_MD5:
c->blocklen = 64;
c->hashlen = 16;
c->init = (void*)av_md5_init;
c->update = (void*)av_md5_update;
c->final = (void*)av_md5_final;
c->hash = av_md5_alloc();
break;
case AV_HMAC_SHA1:
c->blocklen = 64;
c->hashlen = 20;
c->init = sha160_init;
c->update = (void*)av_sha_update;
c->final = (void*)av_sha_final;
c->hash = av_sha_alloc();
break;
case AV_HMAC_SHA224:
#if FF_API_HMAC
case AV_HMAC_SHA224_DEPRECATED:
#endif
c->blocklen = 64;
c->hashlen = 28;
c->init = sha224_init;
c->update = (void*)av_sha_update;
c->final = (void*)av_sha_final;
c->hash = av_sha_alloc();
break;
case AV_HMAC_SHA256:
#if FF_API_HMAC
case AV_HMAC_SHA256_DEPRECATED:
#endif
c->blocklen = 64;
c->hashlen = 32;
c->init = sha256_init;
c->update = (void*)av_sha_update;
c->final = (void*)av_sha_final;
c->hash = av_sha_alloc();
break;
case AV_HMAC_SHA384:
c->blocklen = 128;
c->hashlen = 48;
c->init = sha384_init;
c->update = (void*)av_sha512_update;
c->final = (void*)av_sha512_final;
c->hash = av_sha512_alloc();
break;
case AV_HMAC_SHA512:
c->blocklen = 128;
c->hashlen = 64;
c->init = sha512_init;
c->update = (void*)av_sha512_update;
c->final = (void*)av_sha512_final;
c->hash = av_sha512_alloc();
break;
default:
av_free(c);
return NULL;
}
if (!c->hash) {
av_free(c);
return NULL;
}
return c;
}
void av_hmac_free(AVHMAC *c)
{
if (!c)
return;
av_freep(&c->hash);
av_free(c);
}
void av_hmac_init(AVHMAC *c, const uint8_t *key, unsigned int keylen)
{
int i;
uint8_t block[MAX_BLOCKLEN];
if (keylen > c->blocklen) {
c->init(c->hash);
c->update(c->hash, key, keylen);
c->final(c->hash, c->key);
c->keylen = c->hashlen;
} else {
memcpy(c->key, key, keylen);
c->keylen = keylen;
}
c->init(c->hash);
for (i = 0; i < c->keylen; i++)
block[i] = c->key[i] ^ 0x36;
for (i = c->keylen; i < c->blocklen; i++)
block[i] = 0x36;
c->update(c->hash, block, c->blocklen);
}
void av_hmac_update(AVHMAC *c, const uint8_t *data, unsigned int len)
{
c->update(c->hash, data, len);
}
int av_hmac_final(AVHMAC *c, uint8_t *out, unsigned int outlen)
{
uint8_t block[MAX_BLOCKLEN];
int i;
if (outlen < c->hashlen)
return AVERROR(EINVAL);
c->final(c->hash, out);
c->init(c->hash);
for (i = 0; i < c->keylen; i++)
block[i] = c->key[i] ^ 0x5C;
for (i = c->keylen; i < c->blocklen; i++)
block[i] = 0x5C;
c->update(c->hash, block, c->blocklen);
c->update(c->hash, out, c->hashlen);
c->final(c->hash, out);
return c->hashlen;
}
int av_hmac_calc(AVHMAC *c, const uint8_t *data, unsigned int len,
const uint8_t *key, unsigned int keylen,
uint8_t *out, unsigned int outlen)
{
av_hmac_init(c, key, keylen);
av_hmac_update(c, data, len);
return av_hmac_final(c, out, outlen);
}
#ifdef TEST
#include <stdio.h>
static void test(AVHMAC *hmac, const uint8_t *key, int keylen,
const uint8_t *data, int datalen)
{
uint8_t buf[MAX_HASHLEN];
int out, i;
// Some of the test vectors are strings, where sizeof() includes the
// trailing null byte - remove that.
if (!key[keylen - 1])
keylen--;
if (!data[datalen - 1])
datalen--;
out = av_hmac_calc(hmac, data, datalen, key, keylen, buf, sizeof(buf));
for (i = 0; i < out; i++)
printf("%02x", buf[i]);
printf("\n");
}
int main(void)
{
uint8_t key1[20], key3[131], data3[50];
AVHMAC *hmac;
enum AVHMACType i;
static const uint8_t key2[] = "Jefe";
static const uint8_t data1[] = "Hi There";
static const uint8_t data2[] = "what do ya want for nothing?";
static const uint8_t data4[] = "Test Using Larger Than Block-Size Key - Hash Key First";
static const uint8_t data5[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data";
static const uint8_t data6[] = "This is a test using a larger than block-size key and a larger "
"than block-size data. The key needs to be hashed before being used"
" by the HMAC algorithm.";
memset(key1, 0x0b, sizeof(key1));
memset(key3, 0xaa, sizeof(key3));
memset(data3, 0xdd, sizeof(data3));
/* MD5, SHA-1 */
for (i = AV_HMAC_MD5; i <= AV_HMAC_SHA1; i++) {
hmac = av_hmac_alloc(i);
if (!hmac)
return 1;
// RFC 2202 test vectors
test(hmac, key1, hmac->hashlen, data1, sizeof(data1));
test(hmac, key2, sizeof(key2), data2, sizeof(data2));
test(hmac, key3, hmac->hashlen, data3, sizeof(data3));
test(hmac, key3, 80, data4, sizeof(data4));
test(hmac, key3, 80, data5, sizeof(data5));
av_hmac_free(hmac);
}
/* SHA-2 */
for (i = AV_HMAC_SHA224; i <= AV_HMAC_SHA256; i++) {
hmac = av_hmac_alloc(i);
if (!hmac)
return 1;
// RFC 4231 test vectors
test(hmac, key1, sizeof(key1), data1, sizeof(data1));
test(hmac, key2, sizeof(key2), data2, sizeof(data2));
test(hmac, key3, 20, data3, sizeof(data3));
test(hmac, key3, sizeof(key3), data4, sizeof(data4));
test(hmac, key3, sizeof(key3), data6, sizeof(data6));
av_hmac_free(hmac);
}
for (i = AV_HMAC_SHA384; i <= AV_HMAC_SHA512; i++) {
hmac = av_hmac_alloc(i);
if (!hmac)
return 1;
// RFC 4231 test vectors
test(hmac, key1, sizeof(key1), data1, sizeof(data1));
test(hmac, key2, sizeof(key2), data2, sizeof(data2));
test(hmac, key3, 20, data3, sizeof(data3));
test(hmac, key3, sizeof(key3), data4, sizeof(data4));
test(hmac, key3, sizeof(key3), data6, sizeof(data6));
av_hmac_free(hmac);
}
return 0;
}
#endif /* TEST */