/* md.c - message digest dispatcher
* Copyright (C) 1998 Free Software Foundation, Inc.
*
* This file is part of GNUPG.
*
* GNUPG is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* GNUPG 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*/
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include "util.h"
#include "cipher.h"
#include "errors.h"
/****************
* Open a message digest handle for use with algorithm ALGO.
* More algorithms may be added by md_enable(). The initial algorithm
* may be 0.
*/
MD_HANDLE
md_open( int algo, int secure )
{
MD_HANDLE hd;
hd = secure ? m_alloc_secure_clear( sizeof *hd )
: m_alloc_clear( sizeof *hd );
hd->secure = secure;
if( algo )
md_enable( hd, algo );
fast_random_poll();
return hd;
}
void
md_enable( MD_HANDLE h, int algo )
{
if( algo == DIGEST_ALGO_MD5 ) {
if( !h->use_md5 )
md5_init( &h->md5 );
h->use_md5 = 1;
}
else if( algo == DIGEST_ALGO_RMD160 ) {
if( !h->use_rmd160 )
rmd160_init( &h->rmd160 );
h->use_rmd160 = 1;
}
else if( algo == DIGEST_ALGO_SHA1 ) {
if( !h->use_sha1 )
sha1_init( &h->sha1 );
h->use_sha1 = 1;
}
#ifdef WITH_TIGER_HASH
else if( algo == DIGEST_ALGO_TIGER ) {
if( !h->use_tiger )
tiger_init( &h->tiger );
h->use_tiger = 1;
}
#endif
else
log_bug("md_enable(%d)", algo );
}
MD_HANDLE
md_copy( MD_HANDLE a )
{
MD_HANDLE b;
b = a->secure ? m_alloc_secure( sizeof *b )
: m_alloc( sizeof *b );
memcpy( b, a, sizeof *a );
return b;
}
void
md_close(MD_HANDLE a)
{
if( !a )
return;
if( a->debug )
md_stop_debug(a);
m_free(a);
}
void
md_write( MD_HANDLE a, byte *inbuf, size_t inlen)
{
if( a->debug ) {
if( a->bufcount && fwrite(a->buffer, a->bufcount, 1, a->debug ) != 1 )
BUG();
if( inlen && fwrite(inbuf, inlen, 1, a->debug ) != 1 )
BUG();
}
if( a->use_rmd160 ) {
rmd160_write( &a->rmd160, a->buffer, a->bufcount );
rmd160_write( &a->rmd160, inbuf, inlen );
}
if( a->use_sha1 ) {
sha1_write( &a->sha1, a->buffer, a->bufcount );
sha1_write( &a->sha1, inbuf, inlen );
}
#ifdef WITH_TIGER_HASH
if( a->use_tiger ) {
tiger_write( &a->tiger, a->buffer, a->bufcount );
tiger_write( &a->tiger, inbuf, inlen );
}
#endif
if( a->use_md5 ) {
md5_write( &a->md5, a->buffer, a->bufcount );
md5_write( &a->md5, inbuf, inlen );
}
a->bufcount = 0;
}
void
md_final(MD_HANDLE a)
{
if( a->bufcount )
md_write( a, NULL, 0 );
if( a->use_rmd160 )
rmd160_final( &a->rmd160 );
if( a->use_sha1 )
sha1_final( &a->sha1 );
#ifdef WITH_TIGER_HASH
if( a->use_tiger )
tiger_final( &a->tiger );
#endif
if( a->use_md5 )
md5_final( &a->md5 );
}
/****************
* if ALGO is null get the digest for the used algo (which should be only one)
*/
byte *
md_read( MD_HANDLE a, int algo )
{
if( !algo ) {
if( a->use_rmd160 )
return rmd160_read( &a->rmd160 );
if( a->use_sha1 )
return sha1_read( &a->sha1 );
#ifdef WITH_TIGER_HASH
if( a->use_tiger )
return tiger_read( &a->tiger );
#endif
if( a->use_md5 )
return md5_read( &a->md5 );
}
else {
if( algo == DIGEST_ALGO_RMD160 )
return rmd160_read( &a->rmd160 );
if( algo == DIGEST_ALGO_SHA1 )
return sha1_read( &a->sha1 );
#ifdef WITH_TIGER_HASH
if( algo == DIGEST_ALGO_TIGER )
return tiger_read( &a->tiger );
#endif
if( algo == DIGEST_ALGO_MD5 )
return md5_read( &a->md5 );
}
BUG();
}
int
md_get_algo( MD_HANDLE a )
{
if( a->use_rmd160 )
return DIGEST_ALGO_RMD160;
if( a->use_sha1 )
return DIGEST_ALGO_SHA1;
#ifdef WITH_TIGER_HASH
if( a->use_tiger )
return DIGEST_ALGO_TIGER;
#endif
if( a->use_md5 )
return DIGEST_ALGO_MD5;
return 0;
}
/****************
* Return the length of the digest
*/
int
md_digest_length( int algo )
{
switch( algo ) {
case DIGEST_ALGO_TIGER:
return 24;
case DIGEST_ALGO_RMD160:
case DIGEST_ALGO_SHA1:
return 20;
default:
return 16;
}
}
/* fixme: put the oids in a table and add a mode to enumerate the OIDs
* to make g10/sig-check.c more portable */
const byte *
md_asn_oid( int algo, size_t *asnlen, size_t *mdlen )
{
size_t alen;
byte *p;
if( algo == DIGEST_ALGO_MD5 ) {
static byte asn[18] = /* Object ID is 1.2.840.113549.2.5 */
{ 0x30, 0x20, 0x30, 0x0c, 0x06, 0x08, 0x2a, 0x86,0x48,
0x86, 0xf7, 0x0d, 0x02, 0x05, 0x05, 0x00, 0x04, 0x10 };
alen = DIM(asn); p = asn;
}
else if( algo == DIGEST_ALGO_RMD160 ) {
static byte asn[15] = /* Object ID is 1.3.36.3.2.1 */
{ 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x24, 0x03,
0x02, 0x01, 0x05, 0x00, 0x04, 0x14 };
alen = DIM(asn); p = asn;
}
else if( algo == DIGEST_ALGO_TIGER ) {
/* 40: SEQUENCE {
* 12: SEQUENCE {
* 8: OCTET STRING :54 49 47 45 52 31 39 32
* 0: NULL
* : }
* 24: OCTET STRING
* : }
*
* By replacing the 5th byte (0x04) with 0x16 we would have;
* 8: IA5String 'TIGER192'
*/
static byte asn[18] =
{ 0x30, 0x28, 0x30, 0x0c, 0x04, 0x08, 0x54, 0x49, 0x47,
0x45, 0x52, 0x31, 0x39, 0x32, 0x05, 0x00, 0x04, 0x18 };
alen = DIM(asn); p = asn;
}
else if( algo == DIGEST_ALGO_SHA1 ) {
static byte asn[15] = /* Object ID is 1.3.14.3.2.26 */
{ 0x30, 0x21, 0x30, 0x09, 0x06, 0x05, 0x2b, 0x0e, 0x03,
0x02, 0x1a, 0x05, 0x00, 0x04, 0x14 };
alen = DIM(asn); p = asn;
}
else
log_bug("md_asn_oid(%d)", algo );
if( asnlen )
*asnlen = alen;
if( mdlen )
*mdlen = p[alen-1];
return p;
}
void
md_start_debug( MD_HANDLE md, const char *suffix )
{
static int index=0;
char buf[25];
if( md->debug ) {
log_debug("Oops: md debug already started\n");
return;
}
index++;
sprintf(buf, "dbgmd-%05d.%.10s", index, suffix );
md->debug = fopen(buf, "w");
if( !md->debug )
log_debug("md debug: can't open %s\n", buf );
}
void
md_stop_debug( MD_HANDLE md )
{
if( md->debug ) {
fclose(md->debug);
md->debug = NULL;
}
}