Commit 8ee288d2 authored by Martin Storsjö's avatar Martin Storsjö
Browse files

lavu: Add an API for calculating HMAC (RFC 2104)



This supports HMAC-MD5 and HMAC-SHA1 for now, other hashes are
simple to add.
Signed-off-by: default avatarMartin Storsjö <martin@martin.st>
parent 47812070
......@@ -13,6 +13,9 @@ libavutil: 2012-10-22
API changes, most recent first:
2013-01-xx - xxxxxxx - lavu 52.5.0 - hmac.h
Add AVHMAC.
2013-01-13 - xxxxxxx - lavc 54.36.0 - vdpau.h
Add AVVDPAUContext struct for VDPAU hardware-accelerated decoding.
......
......@@ -19,6 +19,7 @@ HEADERS = adler32.h \
eval.h \
fifo.h \
file.h \
hmac.h \
imgutils.h \
intfloat.h \
intfloat_readwrite.h \
......@@ -66,6 +67,7 @@ OBJS = adler32.o \
fifo.o \
file.o \
float_dsp.o \
hmac.o \
imgutils.o \
intfloat_readwrite.o \
intmath.o \
......
/*
* Copyright (C) 2012 Martin Storsjo
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; 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);
}
/*
* Copyright (C) 2012 Martin Storsjo
*
* This file is part of Libav.
*
* Libav 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.
*
* Libav 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 Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#ifndef AVUTIL_HMAC_H
#define AVUTIL_HMAC_H
#include <stdint.h>
/**
* @defgroup lavu_hmac HMAC
* @ingroup lavu_crypto
* @{
*/
enum AVHMACType {
AV_HMAC_MD5,
AV_HMAC_SHA1,
};
typedef struct AVHMAC AVHMAC;
/**
* Allocate an AVHMAC context.
* @param type The hash function used for the HMAC.
*/
AVHMAC *av_hmac_alloc(enum AVHMACType type);
/**
* Free an AVHMAC context.
* @param ctx The context to free, may be NULL
*/
void av_hmac_free(AVHMAC *ctx);
/**
* Initialize an AVHMAC context with an authentication key.
* @param ctx The HMAC context
* @param key The authentication key
* @param keylen The length of the key, in bytes
*/
void av_hmac_init(AVHMAC *ctx, const uint8_t *key, unsigned int keylen);
/**
* Hash data with the HMAC.
* @param ctx The HMAC context
* @param data The data to hash
* @param len The length of the data, in bytes
*/
void av_hmac_update(AVHMAC *ctx, const uint8_t *data, unsigned int len);
/**
* Finish hashing and output the HMAC digest.
* @param ctx The HMAC context
* @param out The output buffer to write the digest into
* @param outlen The length of the out buffer, in bytes
* @return The number of bytes written to out, or a negative error code.
*/
int av_hmac_final(AVHMAC *ctx, uint8_t *out, unsigned int outlen);
/**
* Hash an array of data with a key.
* @param ctx The HMAC context
* @param data The data to hash
* @param len The length of the data, in bytes
* @param key The authentication key
* @param keylen The length of the key, in bytes
* @param out The output buffer to write the digest into
* @param outlen The length of the out buffer, in bytes
* @return The number of bytes written to out, or a negative error code.
*/
int av_hmac_calc(AVHMAC *ctx, const uint8_t *data, unsigned int len,
const uint8_t *key, unsigned int keylen,
uint8_t *out, unsigned int outlen);
/**
* @}
*/
#endif /* AVUTIL_HMAC_H */
......@@ -37,7 +37,7 @@
*/
#define LIBAVUTIL_VERSION_MAJOR 52
#define LIBAVUTIL_VERSION_MINOR 4
#define LIBAVUTIL_VERSION_MINOR 5
#define LIBAVUTIL_VERSION_MICRO 0
#define LIBAVUTIL_VERSION_INT AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
......
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