1 files changed, 98 insertions, 0 deletions
diff --git a/g10/elg.c b/g10/elg.c
new file mode 100644
index 000000000..9f11d632c
--- /dev/null
+++ b/g10/elg.c
@@ -0,0 +1,98 @@
+/* elg.c
+ *	Copyright (c) 1997 by Werner Koch (dd9jn)
+ *
+ * This file is part of G10.
+ *
+ * G10 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.
+ *
+ * G10 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_elg_encrypt( PKT_public_cert *pkc, PKT_pubkey_enc *enc, DEK *dek )
+{
+    ELG_public_key pkey;
+    MPI frame;
+
+    assert( enc->pubkey_algo == PUBKEY_ALGO_ELGAMAL );
+
+    enc->d.elg.a = mpi_alloc( mpi_get_nlimbs(pkc->d.elg.p) );
+    enc->d.elg.b = mpi_alloc( mpi_get_nlimbs(pkc->d.elg.p) );
+    keyid_from_pkc( pkc, enc->keyid );
+    frame = encode_session_key( dek, mpi_get_nbits(pkc->d.elg.p) );
+    pkey.p = pkc->d.elg.p;
+    pkey.g = pkc->d.elg.g;
+    pkey.y = pkc->d.elg.y;
+    if( DBG_CIPHER )
+	log_mpidump("Plain DEK frame: ", frame);
+    elg_encrypt( enc->d.elg.a, enc->d.elg.b, frame, &pkey);
+    mpi_free( frame );
+    if( DBG_CIPHER ) {
+	log_mpidump("Encry DEK a: ", enc->d.elg.a );
+	log_mpidump("      DEK b: ", enc->d.elg.b );
+    }
+    if( opt.verbose ) {
+	char *ustr = get_user_id_string( enc->keyid );
+	log_info("ElGamal encrypted for: %s\n", ustr );
+	m_free(ustr);
+    }
+}
+
+
+void
+g10_elg_sign( PKT_secret_cert *skc, PKT_signature *sig, MD_HANDLE *md )
+{
+    ELG_secret_key skey;
+    MPI frame;
+    byte *dp;
+
+    assert( sig->pubkey_algo == PUBKEY_ALGO_ELGAMAL );
+
+    dp = md_final( md );
+    keyid_from_skc( skc, sig->keyid );
+    sig->d.elg.digest_algo = md->algo;
+    sig->d.elg.digest_start[0] = dp[0];
+    sig->d.elg.digest_start[1] = dp[1];
+    sig->d.elg.a = mpi_alloc( mpi_get_nlimbs(skc->d.elg.p) );
+    sig->d.elg.b = mpi_alloc( mpi_get_nlimbs(skc->d.elg.p) );
+    frame = encode_md_value( md, mpi_get_nbits(skc->d.elg.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;
+    elg_sign( sig->d.elg.a, sig->d.elg.b, frame, &skey);
+    memset( &skey, 0, sizeof skey );
+    mpi_free(frame);
+    if( opt.verbose ) {
+	char *ustr = get_user_id_string( sig->keyid );
+	log_info("ElGamal signature from: %s\n", ustr );
+	m_free(ustr);
+    }
+}
+