e7e0186eeb
* commit 'ab2ad8bd56882c0ea160b154e8b836eb71abc49d': lavf: Add functions for SRTP decryption/encryption lavu: Add an API for calculating HMAC (RFC 2104) Conflicts: doc/APIchanges libavutil/version.h Merged-by: Michael Niedermayer <michaelni@gmx.at>
139 lines
3.5 KiB
C
139 lines
3.5 KiB
C
/*
|
|
* 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 "hmac.h"
|
|
#include "md5.h"
|
|
#include "sha.h"
|
|
#include "mem.h"
|
|
|
|
#define MAX_HASHLEN 20
|
|
#define MAX_BLOCKLEN 64
|
|
|
|
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;
|
|
};
|
|
|
|
static void sha1_init(void *ctx)
|
|
{
|
|
av_sha_init(ctx, 160);
|
|
}
|
|
|
|
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 = av_md5_init;
|
|
c->update = av_md5_update;
|
|
c->final = av_md5_final;
|
|
c->hash = av_md5_alloc();
|
|
break;
|
|
case AV_HMAC_SHA1:
|
|
c->blocklen = 64;
|
|
c->hashlen = 20;
|
|
c->init = sha1_init;
|
|
c->update = av_sha_update;
|
|
c->final = av_sha_final;
|
|
c->hash = av_sha_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_free(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);
|
|
}
|