- (djm) Merge OpenBSD changes:
- markus@cvs.openbsd.org 2000/11/06 16:04:56
[channels.c channels.h clientloop.c nchan.c serverloop.c]
[session.c ssh.c]
agent forwarding and -R for ssh2, based on work from
jhuuskon@messi.uku.fi
- markus@cvs.openbsd.org 2000/11/06 16:13:27
[ssh.c sshconnect.c sshd.c]
do not disabled rhosts(rsa) if server port > 1024; from
pekkas@netcore.fi
- markus@cvs.openbsd.org 2000/11/06 16:16:35
[sshconnect.c]
downgrade client to 1.3 if server is 1.4; help from mdb@juniper.net
- markus@cvs.openbsd.org 2000/11/09 18:04:40
[auth1.c]
typo; from mouring@pconline.com
- markus@cvs.openbsd.org 2000/11/12 12:03:28
[ssh-agent.c]
off-by-one when removing a key from the agent
- markus@cvs.openbsd.org 2000/11/12 12:50:39
[auth-rh-rsa.c auth2.c authfd.c authfd.h]
[authfile.c hostfile.c kex.c kex.h key.c key.h myproposal.h]
[readconf.c readconf.h rsa.c rsa.h servconf.c servconf.h ssh-add.c]
[ssh-agent.c ssh-keygen.1 ssh-keygen.c ssh.1 ssh.c ssh_config]
[sshconnect1.c sshconnect2.c sshd.8 sshd.c sshd_config ssh-dss.c]
[ssh-dss.h ssh-rsa.c ssh-rsa.h dsa.c dsa.h]
add support for RSA to SSH2. please test.
there are now 3 types of keys: RSA1 is used by ssh-1 only,
RSA and DSA are used by SSH2.
you can use 'ssh-keygen -t rsa -f ssh2_rsa_file' to generate RSA
keys for SSH2 and use the RSA keys for hostkeys or for user keys.
SSH2 RSA or DSA keys are added to .ssh/authorised_keys2 as before.
- (djm) Fix up Makefile and Redhat init script to create RSA host keys
- (djm) Change to interim version
diff --git a/ssh-dss.c b/ssh-dss.c
new file mode 100644
index 0000000..fea1fe2
--- /dev/null
+++ b/ssh-dss.c
@@ -0,0 +1,216 @@
+/*
+ * Copyright (c) 2000 Markus Friedl. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: ssh-dss.c,v 1.1 2000/11/12 19:50:38 markus Exp $");
+
+#include "ssh.h"
+#include "xmalloc.h"
+#include "buffer.h"
+#include "bufaux.h"
+#include "compat.h"
+
+#include <openssl/bn.h>
+#include <openssl/rsa.h>
+#include <openssl/dsa.h>
+#include <openssl/evp.h>
+
+#include "key.h"
+
+#define INTBLOB_LEN 20
+#define SIGBLOB_LEN (2*INTBLOB_LEN)
+
+int
+ssh_dss_sign(
+ Key *key,
+ unsigned char **sigp, int *lenp,
+ unsigned char *data, int datalen)
+{
+ unsigned char *digest;
+ unsigned char *ret;
+ DSA_SIG *sig;
+ EVP_MD *evp_md = EVP_sha1();
+ EVP_MD_CTX md;
+ unsigned int rlen;
+ unsigned int slen;
+ unsigned int len;
+ unsigned char sigblob[SIGBLOB_LEN];
+ Buffer b;
+
+ if (key == NULL || key->type != KEY_DSA || key->dsa == NULL) {
+ error("ssh_dss_sign: no DSA key");
+ return -1;
+ }
+ digest = xmalloc(evp_md->md_size);
+ EVP_DigestInit(&md, evp_md);
+ EVP_DigestUpdate(&md, data, datalen);
+ EVP_DigestFinal(&md, digest, NULL);
+
+ sig = DSA_do_sign(digest, evp_md->md_size, key->dsa);
+ if (sig == NULL) {
+ fatal("ssh_dss_sign: cannot sign");
+ }
+
+ rlen = BN_num_bytes(sig->r);
+ slen = BN_num_bytes(sig->s);
+ if (rlen > INTBLOB_LEN || slen > INTBLOB_LEN) {
+ error("bad sig size %d %d", rlen, slen);
+ DSA_SIG_free(sig);
+ return -1;
+ }
+ debug("sig size %d %d", rlen, slen);
+
+ memset(sigblob, 0, SIGBLOB_LEN);
+ BN_bn2bin(sig->r, sigblob+ SIGBLOB_LEN - INTBLOB_LEN - rlen);
+ BN_bn2bin(sig->s, sigblob+ SIGBLOB_LEN - slen);
+ DSA_SIG_free(sig);
+
+ if (datafellows & SSH_BUG_SIGBLOB) {
+ debug("datafellows");
+ ret = xmalloc(SIGBLOB_LEN);
+ memcpy(ret, sigblob, SIGBLOB_LEN);
+ if (lenp != NULL)
+ *lenp = SIGBLOB_LEN;
+ if (sigp != NULL)
+ *sigp = ret;
+ } else {
+ /* ietf-drafts */
+ buffer_init(&b);
+ buffer_put_cstring(&b, "ssh-dss");
+ buffer_put_string(&b, sigblob, SIGBLOB_LEN);
+ len = buffer_len(&b);
+ ret = xmalloc(len);
+ memcpy(ret, buffer_ptr(&b), len);
+ buffer_free(&b);
+ if (lenp != NULL)
+ *lenp = len;
+ if (sigp != NULL)
+ *sigp = ret;
+ }
+ return 0;
+}
+int
+ssh_dss_verify(
+ Key *key,
+ unsigned char *signature, int signaturelen,
+ unsigned char *data, int datalen)
+{
+ Buffer b;
+ unsigned char *digest;
+ DSA_SIG *sig;
+ EVP_MD *evp_md = EVP_sha1();
+ EVP_MD_CTX md;
+ unsigned char *sigblob;
+ char *txt;
+ unsigned int len, dlen;
+ int rlen;
+ int ret;
+
+ if (key == NULL || key->type != KEY_DSA || key->dsa == NULL) {
+ error("ssh_dss_verify: no DSA key");
+ return -1;
+ }
+
+ if (!(datafellows & SSH_BUG_SIGBLOB) &&
+ signaturelen == SIGBLOB_LEN) {
+ datafellows |= ~SSH_BUG_SIGBLOB;
+ log("autodetect SSH_BUG_SIGBLOB");
+ } else if ((datafellows & SSH_BUG_SIGBLOB) &&
+ signaturelen != SIGBLOB_LEN) {
+ log("autoremove SSH_BUG_SIGBLOB");
+ datafellows &= ~SSH_BUG_SIGBLOB;
+ }
+
+ debug("len %d datafellows %d", signaturelen, datafellows);
+
+ /* fetch signature */
+ if (datafellows & SSH_BUG_SIGBLOB) {
+ sigblob = signature;
+ len = signaturelen;
+ } else {
+ /* ietf-drafts */
+ char *ktype;
+ buffer_init(&b);
+ buffer_append(&b, (char *) signature, signaturelen);
+ ktype = buffer_get_string(&b, NULL);
+ if (strcmp("ssh-dss", ktype) != 0) {
+ error("ssh_dss_verify: cannot handle type %s", ktype);
+ buffer_free(&b);
+ return -1;
+ }
+ sigblob = (unsigned char *)buffer_get_string(&b, &len);
+ rlen = buffer_len(&b);
+ if(rlen != 0) {
+ error("remaining bytes in signature %d", rlen);
+ buffer_free(&b);
+ return -1;
+ }
+ buffer_free(&b);
+ xfree(ktype);
+ }
+
+ if (len != SIGBLOB_LEN) {
+ fatal("bad sigbloblen %d != SIGBLOB_LEN", len);
+ }
+
+ /* parse signature */
+ sig = DSA_SIG_new();
+ sig->r = BN_new();
+ sig->s = BN_new();
+ BN_bin2bn(sigblob, INTBLOB_LEN, sig->r);
+ BN_bin2bn(sigblob+ INTBLOB_LEN, INTBLOB_LEN, sig->s);
+
+ if (!(datafellows & SSH_BUG_SIGBLOB)) {
+ memset(sigblob, 0, len);
+ xfree(sigblob);
+ }
+
+ /* sha1 the data */
+ dlen = evp_md->md_size;
+ digest = xmalloc(dlen);
+ EVP_DigestInit(&md, evp_md);
+ EVP_DigestUpdate(&md, data, datalen);
+ EVP_DigestFinal(&md, digest, NULL);
+
+ ret = DSA_do_verify(digest, dlen, sig, key->dsa);
+
+ memset(digest, 0, dlen);
+ xfree(digest);
+ DSA_SIG_free(sig);
+
+ switch (ret) {
+ case 1:
+ txt = "correct";
+ break;
+ case 0:
+ txt = "incorrect";
+ break;
+ case -1:
+ default:
+ txt = "error";
+ break;
+ }
+ debug("ssh_dss_verify: signature %s", txt);
+ return ret;
+}