rpm/beecrypt/hmac.c

142 lines
3.4 KiB
C

/** \ingroup HMAC_m
* \file hmac.c
*
* HMAC message authentication code, code.
*/
/*
* Copyright (c) 1999, 2000, 2002 Virtual Unlimited B.V.
*
* Author: Bob Deblier <bob@virtualunlimited.com>
*
* This library 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.
*
* This library 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 this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
*/
#include "system.h"
#include "hmac.h"
#include "mp32.h"
#include "endianness.h"
#include "debug.h"
#define HMAC_IPAD 0x36
#define HMAC_OPAD 0x5c
/*@-boundswrite@*/
int hmacSetup(hmacParam* hp, const hashFunction* hash, hashFunctionParam* param, const uint32* key, int keybits)
{
register int i, rc;
int keywords = (((uint32)keybits + 31) >> 5); /* rounded up */
int keybytes = (((uint32)keybits ) >> 3);
/* if the key is too large, hash it first */
if (keybytes > 64)
{
uint32 keydigest[16];
byte* tmp;
/* if the hash digest is too large, this doesn't help */
if (hash->digestsize > 64)
return -1;
if (hash->reset(param))
return -1;
tmp = (byte*) malloc(keybytes);
if (tmp == (byte*) 0)
return -1;
/* before we can hash the key, we need to encode it! */
(void) encodeIntsPartial(key, tmp, keybytes);
rc = hash->update(param, tmp, keybytes);
free(tmp);
if (rc)
return -1;
memset(keydigest, 0, sizeof(keydigest));
if (hash->digest(param, keydigest))
return -1;
keywords = hash->digestsize >> 2;
keybytes = hash->digestsize;
(void) encodeInts(keydigest, hp->kxi, keybytes);
(void) encodeInts(keydigest, hp->kxo, keybytes);
}
else if (keybytes > 0)
{
(void) encodeIntsPartial(key, hp->kxi, keybytes);
(void) encodeIntsPartial(key, hp->kxo, keybytes);
}
else
return -1;
for (i = 0; i < keybytes; i++)
{
hp->kxi[i] ^= HMAC_IPAD;
hp->kxo[i] ^= HMAC_OPAD;
}
for (i = keybytes; i < 64; i++)
{
hp->kxi[i] = HMAC_IPAD;
hp->kxo[i] = HMAC_OPAD;
}
return hmacReset(hp, hash, param);
}
/*@=boundswrite@*/
int hmacReset(hmacParam* hp, const hashFunction* hash, hashFunctionParam* param)
{
if (hash->reset(param))
return -1;
if (hash->update(param, hp->kxi, 64))
return -1;
return 0;
}
int hmacUpdate(/*@unused@*/ hmacParam* hp, const hashFunction* hash, hashFunctionParam* param, const byte* data, int size)
{
return hash->update(param, data, size);
}
int hmacDigest(hmacParam* hp, const hashFunction* hash, hashFunctionParam* param, uint32* data)
{
if (hash->digest(param, data))
return -1;
if (hash->update(param, hp->kxo, 64))
return -1;
/* digestsize is in bytes; divide by 4 to get the number of words */
/*@-compdef@*/ /* FIX: *data undef ??? Code looks bogus ... */
(void) encodeInts((const javaint*) data, (byte*) data, hash->digestsize >> 2);
/*@=compdef@*/
if (hash->update(param, (const byte*) data, hash->digestsize))
return -1;
if (hash->digest(param, data))
return -1;
return 0;
}