gnupg/g10/dsa.c

72 lines
2.0 KiB
C

/* dsa.c
* 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 <assert.h>
#include "options.h"
#include "packet.h"
#include "errors.h"
#include "iobuf.h"
#include "keydb.h"
#include "memory.h"
#include "util.h"
#include "main.h"
void
g10_dsa_sign( PKT_secret_cert *skc, PKT_signature *sig,
MD_HANDLE md, int digest_algo )
{
DSA_secret_key skey;
MPI frame;
byte *dp;
assert( sig->pubkey_algo == PUBKEY_ALGO_DSA );
if( !digest_algo )
digest_algo = md_get_algo(md);
dp = md_read( md, digest_algo );
keyid_from_skc( skc, sig->keyid );
sig->digest_algo = digest_algo;
sig->digest_start[0] = dp[0];
sig->digest_start[1] = dp[1];
sig->d.dsa.r = mpi_alloc( mpi_get_nlimbs(skc->d.dsa.p) );
sig->d.dsa.s = mpi_alloc( mpi_get_nlimbs(skc->d.dsa.p) );
frame = encode_md_value( md, mpi_get_nbits(skc->d.dsa.p));
skey.p = skc->d.elg.p;
skey.g = skc->d.elg.g;
skey.y = skc->d.elg.y;
skey.x = skc->d.elg.x;
dsa_sign( sig->d.dsa.r, sig->d.dsa.s, frame, &skey);
memset( &skey, 0, sizeof skey );
mpi_free(frame);
if( opt.verbose ) {
char *ustr = get_user_id_string( sig->keyid );
log_info("DSA signature from: %s\n", ustr );
m_free(ustr);
}
}