vendor/openssh/2.1

1 files changed, 115 insertions, 1055 deletions

diff --git a/crypto/openssh/sshconnect.c b/crypto/openssh/sshconnect.c
index 07277986949e..80beac30680a 100644
--- a/crypto/openssh/sshconnect.c
+++ b/crypto/openssh/sshconnect.c
@@ -8,31 +8,26 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect.c,v 1.58 2000/03/23 22:15:33 markus Exp $");
+RCSID("$OpenBSD: sshconnect.c,v 1.72 2000/05/04 09:50:22 markus Exp $");
+
+#include <openssl/bn.h>
+#include <openssl/dsa.h>
+#include <openssl/rsa.h>
 
-#include <ssl/bn.h>
 #include "xmalloc.h"
 #include "rsa.h"
 #include "ssh.h"
+#include "buffer.h"
 #include "packet.h"
-#include "authfd.h"
-#include "cipher.h"
-#include "mpaux.h"
 #include "uidswap.h"
 #include "compat.h"
 #include "readconf.h"
-
-#include <ssl/rsa.h>
-#include <ssl/dsa.h>
-#include <ssl/md5.h>
 #include "key.h"
+#include "sshconnect.h"
 #include "hostfile.h"
 
-/* Session id for the current session. */
-unsigned char session_id[16];
-
-/* authentications supported by server */
-unsigned int supported_authentications;
+char *client_version_string = NULL;
+char *server_version_string = NULL;
 
 extern Options options;
 extern char *__progname;
@@ -48,7 +43,7 @@ ssh_proxy_connect(const char *host, u_short port, uid_t original_real_uid,
 	const char *cp;
 	char *command_string;
 	int pin[2], pout[2];
-	int pid;
+	pid_t pid;
 	char strport[NI_MAXSERV];
 
 	/* Convert the port number into a string. */
@@ -229,7 +224,7 @@ ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
 			debug("Trying again...");
 
 		/* Loop through addresses for this host, and try each one in
- 		   sequence until the connection succeeds. */
+		   sequence until the connection succeeds. */
 		for (ai = aitop; ai; ai = ai->ai_next) {
 			if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
 				continue;
@@ -243,7 +238,7 @@ ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
 				host, ntop, strport);
 
 			/* Create a socket for connecting. */
-			sock = ssh_create_socket(original_real_uid, 
+			sock = ssh_create_socket(original_real_uid,
 			    !anonymous && geteuid() == 0 && port < IPPORT_RESERVED,
 			    ai->ai_family);
 			if (sock < 0)
@@ -302,651 +297,19 @@ ssh_connect(const char *host, struct sockaddr_storage * hostaddr,
 	return 1;
 }
 
-/*
- * Checks if the user has an authentication agent, and if so, tries to
- * authenticate using the agent.
- */
-int
-try_agent_authentication()
-{
-	int status, type;
-	char *comment;
-	AuthenticationConnection *auth;
-	unsigned char response[16];
-	unsigned int i;
-	BIGNUM *e, *n, *challenge;
-
-	/* Get connection to the agent. */
-	auth = ssh_get_authentication_connection();
-	if (!auth)
-		return 0;
-
-	e = BN_new();
-	n = BN_new();
-	challenge = BN_new();
-
-	/* Loop through identities served by the agent. */
-	for (status = ssh_get_first_identity(auth, e, n, &comment);
-	     status;
-	     status = ssh_get_next_identity(auth, e, n, &comment)) {
-		int plen, clen;
-
-		/* Try this identity. */
-		debug("Trying RSA authentication via agent with '%.100s'", comment);
-		xfree(comment);
-
-		/* Tell the server that we are willing to authenticate using this key. */
-		packet_start(SSH_CMSG_AUTH_RSA);
-		packet_put_bignum(n);
-		packet_send();
-		packet_write_wait();
-
-		/* Wait for server's response. */
-		type = packet_read(&plen);
-
-		/* The server sends failure if it doesn\'t like our key or
-		   does not support RSA authentication. */
-		if (type == SSH_SMSG_FAILURE) {
-			debug("Server refused our key.");
-			continue;
-		}
-		/* Otherwise it should have sent a challenge. */
-		if (type != SSH_SMSG_AUTH_RSA_CHALLENGE)
-			packet_disconnect("Protocol error during RSA authentication: %d",
-					  type);
-
-		packet_get_bignum(challenge, &clen);
-
-		packet_integrity_check(plen, clen, type);
-
-		debug("Received RSA challenge from server.");
-
-		/* Ask the agent to decrypt the challenge. */
-		if (!ssh_decrypt_challenge(auth, e, n, challenge,
-					   session_id, 1, response)) {
-			/* The agent failed to authenticate this identifier although it
-			   advertised it supports this.  Just return a wrong value. */
-			log("Authentication agent failed to decrypt challenge.");
-			memset(response, 0, sizeof(response));
-		}
-		debug("Sending response to RSA challenge.");
-
-		/* Send the decrypted challenge back to the server. */
-		packet_start(SSH_CMSG_AUTH_RSA_RESPONSE);
-		for (i = 0; i < 16; i++)
-			packet_put_char(response[i]);
-		packet_send();
-		packet_write_wait();
-
-		/* Wait for response from the server. */
-		type = packet_read(&plen);
-
-		/* The server returns success if it accepted the authentication. */
-		if (type == SSH_SMSG_SUCCESS) {
-			debug("RSA authentication accepted by server.");
-			BN_clear_free(e);
-			BN_clear_free(n);
-			BN_clear_free(challenge);
-			return 1;
-		}
-		/* Otherwise it should return failure. */
-		if (type != SSH_SMSG_FAILURE)
-			packet_disconnect("Protocol error waiting RSA auth response: %d",
-					  type);
-	}
-
-	BN_clear_free(e);
-	BN_clear_free(n);
-	BN_clear_free(challenge);
-
-	debug("RSA authentication using agent refused.");
-	return 0;
-}
-
-/*
- * Computes the proper response to a RSA challenge, and sends the response to
- * the server.
- */
-void
-respond_to_rsa_challenge(BIGNUM * challenge, RSA * prv)
-{
-	unsigned char buf[32], response[16];
-	MD5_CTX md;
-	int i, len;
-
-	/* Decrypt the challenge using the private key. */
-	rsa_private_decrypt(challenge, challenge, prv);
-
-	/* Compute the response. */
-	/* The response is MD5 of decrypted challenge plus session id. */
-	len = BN_num_bytes(challenge);
-	if (len <= 0 || len > sizeof(buf))
-		packet_disconnect("respond_to_rsa_challenge: bad challenge length %d",
-				  len);
-
-	memset(buf, 0, sizeof(buf));
-	BN_bn2bin(challenge, buf + sizeof(buf) - len);
-	MD5_Init(&md);
-	MD5_Update(&md, buf, 32);
-	MD5_Update(&md, session_id, 16);
-	MD5_Final(response, &md);
-
-	debug("Sending response to host key RSA challenge.");
-
-	/* Send the response back to the server. */
-	packet_start(SSH_CMSG_AUTH_RSA_RESPONSE);
-	for (i = 0; i < 16; i++)
-		packet_put_char(response[i]);
-	packet_send();
-	packet_write_wait();
-
-	memset(buf, 0, sizeof(buf));
-	memset(response, 0, sizeof(response));
-	memset(&md, 0, sizeof(md));
-}
-
-/*
- * Checks if the user has authentication file, and if so, tries to authenticate
- * the user using it.
- */
-int
-try_rsa_authentication(const char *authfile)
-{
-	BIGNUM *challenge;
-	RSA *private_key;
-	RSA *public_key;
-	char *passphrase, *comment;
-	int type, i;
-	int plen, clen;
-
-	/* Try to load identification for the authentication key. */
-	public_key = RSA_new();
-	if (!load_public_key(authfile, public_key, &comment)) {
-		RSA_free(public_key);
-		/* Could not load it.  Fail. */
-		return 0;
-	}
-	debug("Trying RSA authentication with key '%.100s'", comment);
-
-	/* Tell the server that we are willing to authenticate using this key. */
-	packet_start(SSH_CMSG_AUTH_RSA);
-	packet_put_bignum(public_key->n);
-	packet_send();
-	packet_write_wait();
-
-	/* We no longer need the public key. */
-	RSA_free(public_key);
-
-	/* Wait for server's response. */
-	type = packet_read(&plen);
-
-	/*
-	 * The server responds with failure if it doesn\'t like our key or
-	 * doesn\'t support RSA authentication.
-	 */
-	if (type == SSH_SMSG_FAILURE) {
-		debug("Server refused our key.");
-		xfree(comment);
-		return 0;
-	}
-	/* Otherwise, the server should respond with a challenge. */
-	if (type != SSH_SMSG_AUTH_RSA_CHALLENGE)
-		packet_disconnect("Protocol error during RSA authentication: %d", type);
-
-	/* Get the challenge from the packet. */
-	challenge = BN_new();
-	packet_get_bignum(challenge, &clen);
-
-	packet_integrity_check(plen, clen, type);
-
-	debug("Received RSA challenge from server.");
-
-	private_key = RSA_new();
-	/*
-	 * Load the private key.  Try first with empty passphrase; if it
-	 * fails, ask for a passphrase.
-	 */
-	if (!load_private_key(authfile, "", private_key, NULL)) {
-		char buf[300];
-		snprintf(buf, sizeof buf, "Enter passphrase for RSA key '%.100s': ",
-		    comment);
-		if (!options.batch_mode)
-			passphrase = read_passphrase(buf, 0);
-		else {
-			debug("Will not query passphrase for %.100s in batch mode.",
-			      comment);
-			passphrase = xstrdup("");
-		}
-
-		/* Load the authentication file using the pasphrase. */
-		if (!load_private_key(authfile, passphrase, private_key, NULL)) {
-			memset(passphrase, 0, strlen(passphrase));
-			xfree(passphrase);
-			error("Bad passphrase.");
-
-			/* Send a dummy response packet to avoid protocol error. */
-			packet_start(SSH_CMSG_AUTH_RSA_RESPONSE);
-			for (i = 0; i < 16; i++)
-				packet_put_char(0);
-			packet_send();
-			packet_write_wait();
-
-			/* Expect the server to reject it... */
-			packet_read_expect(&plen, SSH_SMSG_FAILURE);
-			xfree(comment);
-			return 0;
-		}
-		/* Destroy the passphrase. */
-		memset(passphrase, 0, strlen(passphrase));
-		xfree(passphrase);
-	}
-	/* We no longer need the comment. */
-	xfree(comment);
-
-	/* Compute and send a response to the challenge. */
-	respond_to_rsa_challenge(challenge, private_key);
-
-	/* Destroy the private key. */
-	RSA_free(private_key);
-
-	/* We no longer need the challenge. */
-	BN_clear_free(challenge);
-
-	/* Wait for response from the server. */
-	type = packet_read(&plen);
-	if (type == SSH_SMSG_SUCCESS) {
-		debug("RSA authentication accepted by server.");
-		return 1;
-	}
-	if (type != SSH_SMSG_FAILURE)
-		packet_disconnect("Protocol error waiting RSA auth response: %d", type);
-	debug("RSA authentication refused.");
-	return 0;
-}
-
-/*
- * Tries to authenticate the user using combined rhosts or /etc/hosts.equiv
- * authentication and RSA host authentication.
- */
-int
-try_rhosts_rsa_authentication(const char *local_user, RSA * host_key)
-{
-	int type;
-	BIGNUM *challenge;
-	int plen, clen;
-
-	debug("Trying rhosts or /etc/hosts.equiv with RSA host authentication.");
-
-	/* Tell the server that we are willing to authenticate using this key. */
-	packet_start(SSH_CMSG_AUTH_RHOSTS_RSA);
-	packet_put_string(local_user, strlen(local_user));
-	packet_put_int(BN_num_bits(host_key->n));
-	packet_put_bignum(host_key->e);
-	packet_put_bignum(host_key->n);
-	packet_send();
-	packet_write_wait();
-
-	/* Wait for server's response. */
-	type = packet_read(&plen);
-
-	/* The server responds with failure if it doesn't admit our
-	   .rhosts authentication or doesn't know our host key. */
-	if (type == SSH_SMSG_FAILURE) {
-		debug("Server refused our rhosts authentication or host key.");
-		return 0;
-	}
-	/* Otherwise, the server should respond with a challenge. */
-	if (type != SSH_SMSG_AUTH_RSA_CHALLENGE)
-		packet_disconnect("Protocol error during RSA authentication: %d", type);
-
-	/* Get the challenge from the packet. */
-	challenge = BN_new();
-	packet_get_bignum(challenge, &clen);
-
-	packet_integrity_check(plen, clen, type);
-
-	debug("Received RSA challenge for host key from server.");
-
-	/* Compute a response to the challenge. */
-	respond_to_rsa_challenge(challenge, host_key);
-
-	/* We no longer need the challenge. */
-	BN_clear_free(challenge);
-
-	/* Wait for response from the server. */
-	type = packet_read(&plen);
-	if (type == SSH_SMSG_SUCCESS) {
-		debug("Rhosts or /etc/hosts.equiv with RSA host authentication accepted by server.");
-		return 1;
-	}
-	if (type != SSH_SMSG_FAILURE)
-		packet_disconnect("Protocol error waiting RSA auth response: %d", type);
-	debug("Rhosts or /etc/hosts.equiv with RSA host authentication refused.");
-	return 0;
-}
-
-#ifdef KRB4
-int
-try_kerberos_authentication()
+char *
+chop(char *s)
 {
-	KTEXT_ST auth;		/* Kerberos data */
-	char *reply;
-	char inst[INST_SZ];
-	char *realm;
-	CREDENTIALS cred;
-	int r, type, plen;
-	socklen_t slen;
-	Key_schedule schedule;
-	u_long checksum, cksum;
-	MSG_DAT msg_data;
-	struct sockaddr_in local, foreign;
-	struct stat st;
-
-	/* Don't do anything if we don't have any tickets. */
-	if (stat(tkt_string(), &st) < 0)
-		return 0;
-
-	strncpy(inst, (char *) krb_get_phost(get_canonical_hostname()), INST_SZ);
-
-	realm = (char *) krb_realmofhost(get_canonical_hostname());
-	if (!realm) {
-		debug("Kerberos V4: no realm for %s", get_canonical_hostname());
-		return 0;
-	}
-	/* This can really be anything. */
-	checksum = (u_long) getpid();
-
-	r = krb_mk_req(&auth, KRB4_SERVICE_NAME, inst, realm, checksum);
-	if (r != KSUCCESS) {
-		debug("Kerberos V4 krb_mk_req failed: %s", krb_err_txt[r]);
-		return 0;
-	}
-	/* Get session key to decrypt the server's reply with. */
-	r = krb_get_cred(KRB4_SERVICE_NAME, inst, realm, &cred);
-	if (r != KSUCCESS) {
-		debug("get_cred failed: %s", krb_err_txt[r]);
-		return 0;
-	}
-	des_key_sched((des_cblock *) cred.session, schedule);
-
-	/* Send authentication info to server. */
-	packet_start(SSH_CMSG_AUTH_KERBEROS);
-	packet_put_string((char *) auth.dat, auth.length);
-	packet_send();
-	packet_write_wait();
-
-	/* Zero the buffer. */
-	(void) memset(auth.dat, 0, MAX_KTXT_LEN);
-
-	slen = sizeof(local);
-	memset(&local, 0, sizeof(local));
-	if (getsockname(packet_get_connection_in(),
-			(struct sockaddr *) & local, &slen) < 0)
-		debug("getsockname failed: %s", strerror(errno));
-
-	slen = sizeof(foreign);
-	memset(&foreign, 0, sizeof(foreign));
-	if (getpeername(packet_get_connection_in(),
-			(struct sockaddr *) & foreign, &slen) < 0) {
-		debug("getpeername failed: %s", strerror(errno));
-		fatal_cleanup();
-	}
-	/* Get server reply. */
-	type = packet_read(&plen);
-	switch (type) {
-	case SSH_SMSG_FAILURE:
-		/* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */
-		debug("Kerberos V4 authentication failed.");
-		return 0;
-		break;
-
-	case SSH_SMSG_AUTH_KERBEROS_RESPONSE:
-		/* SSH_SMSG_AUTH_KERBEROS_SUCCESS */
-		debug("Kerberos V4 authentication accepted.");
-
-		/* Get server's response. */
-		reply = packet_get_string((unsigned int *) &auth.length);
-		memcpy(auth.dat, reply, auth.length);
-		xfree(reply);
-
-		packet_integrity_check(plen, 4 + auth.length, type);
-
-		/*
-		 * If his response isn't properly encrypted with the session
-		 * key, and the decrypted checksum fails to match, he's
-		 * bogus. Bail out.
-		 */
-		r = krb_rd_priv(auth.dat, auth.length, schedule, &cred.session,
-				&foreign, &local, &msg_data);
-		if (r != KSUCCESS) {
-			debug("Kerberos V4 krb_rd_priv failed: %s", krb_err_txt[r]);
-			packet_disconnect("Kerberos V4 challenge failed!");
+	char *t = s;
+	while (*t) {
+		if(*t == '\n' || *t == '\r') {
+			*t = '\0';
+			return s;
 		}
-		/* Fetch the (incremented) checksum that we supplied in the request. */
-		(void) memcpy((char *) &cksum, (char *) msg_data.app_data, sizeof(cksum));
-		cksum = ntohl(cksum);
-
-		/* If it matches, we're golden. */
-		if (cksum == checksum + 1) {
-			debug("Kerberos V4 challenge successful.");
-			return 1;
-		} else
-			packet_disconnect("Kerberos V4 challenge failed!");
-		break;
-
-	default:
-		packet_disconnect("Protocol error on Kerberos V4 response: %d", type);
-	}
-	return 0;
-}
-
-#endif /* KRB4 */
-
-#ifdef AFS
-int
-send_kerberos_tgt()
-{
-	CREDENTIALS *creds;
-	char pname[ANAME_SZ], pinst[INST_SZ], prealm[REALM_SZ];
-	int r, type, plen;
-	char buffer[8192];
-	struct stat st;
-
-	/* Don't do anything if we don't have any tickets. */
-	if (stat(tkt_string(), &st) < 0)
-		return 0;
-
-	creds = xmalloc(sizeof(*creds));
-
-	if ((r = krb_get_tf_fullname(TKT_FILE, pname, pinst, prealm)) != KSUCCESS) {
-		debug("Kerberos V4 tf_fullname failed: %s", krb_err_txt[r]);
-		return 0;
-	}
-	if ((r = krb_get_cred("krbtgt", prealm, prealm, creds)) != GC_OK) {
-		debug("Kerberos V4 get_cred failed: %s", krb_err_txt[r]);
-		return 0;
-	}
-	if (time(0) > krb_life_to_time(creds->issue_date, creds->lifetime)) {
-		debug("Kerberos V4 ticket expired: %s", TKT_FILE);
-		return 0;
-	}
-	creds_to_radix(creds, (unsigned char *)buffer);
-	xfree(creds);
-
-	packet_start(SSH_CMSG_HAVE_KERBEROS_TGT);
-	packet_put_string(buffer, strlen(buffer));
-	packet_send();
-	packet_write_wait();
-
-	type = packet_read(&plen);
-
-	if (type == SSH_SMSG_FAILURE)
-		debug("Kerberos TGT for realm %s rejected.", prealm);
-	else if (type != SSH_SMSG_SUCCESS)
-		packet_disconnect("Protocol error on Kerberos TGT response: %d", type);
-
-	return 1;
-}
-
-void
-send_afs_tokens(void)
-{
-	CREDENTIALS creds;
-	struct ViceIoctl parms;
-	struct ClearToken ct;
-	int i, type, len, plen;
-	char buf[2048], *p, *server_cell;
-	char buffer[8192];
-
-	/* Move over ktc_GetToken, here's something leaner. */
-	for (i = 0; i < 100; i++) {	/* just in case */
-		parms.in = (char *) &i;
-		parms.in_size = sizeof(i);
-		parms.out = buf;
-		parms.out_size = sizeof(buf);
-		if (k_pioctl(0, VIOCGETTOK, &parms, 0) != 0)
-			break;
-		p = buf;
-
-		/* Get secret token. */
-		memcpy(&creds.ticket_st.length, p, sizeof(unsigned int));
-		if (creds.ticket_st.length > MAX_KTXT_LEN)
-			break;
-		p += sizeof(unsigned int);
-		memcpy(creds.ticket_st.dat, p, creds.ticket_st.length);
-		p += creds.ticket_st.length;
-
-		/* Get clear token. */
-		memcpy(&len, p, sizeof(len));
-		if (len != sizeof(struct ClearToken))
-			break;
-		p += sizeof(len);
-		memcpy(&ct, p, len);
-		p += len;
-		p += sizeof(len);	/* primary flag */
-		server_cell = p;
-
-		/* Flesh out our credentials. */
-		strlcpy(creds.service, "afs", sizeof creds.service);
-		creds.instance[0] = '\0';
-		strlcpy(creds.realm, server_cell, REALM_SZ);
-		memcpy(creds.session, ct.HandShakeKey, DES_KEY_SZ);
-		creds.issue_date = ct.BeginTimestamp;
-		creds.lifetime = krb_time_to_life(creds.issue_date, ct.EndTimestamp);
-		creds.kvno = ct.AuthHandle;
-		snprintf(creds.pname, sizeof(creds.pname), "AFS ID %d", ct.ViceId);
-		creds.pinst[0] = '\0';
-
-		/* Encode token, ship it off. */
-		if (!creds_to_radix(&creds, (unsigned char*) buffer))
-			break;
-		packet_start(SSH_CMSG_HAVE_AFS_TOKEN);
-		packet_put_string(buffer, strlen(buffer));
-		packet_send();
-		packet_write_wait();
-
-		/* Roger, Roger. Clearance, Clarence. What's your vector,
-		   Victor? */
-		type = packet_read(&plen);
-
-		if (type == SSH_SMSG_FAILURE)
-			debug("AFS token for cell %s rejected.", server_cell);
-		else if (type != SSH_SMSG_SUCCESS)
-			packet_disconnect("Protocol error on AFS token response: %d", type);
-	}
-}
-
-#endif /* AFS */
-
-/*
- * Tries to authenticate with any string-based challenge/response system.
- * Note that the client code is not tied to s/key or TIS.
- */
-int
-try_skey_authentication()
-{
-	int type, i;
-	int payload_len;
-	unsigned int clen;
-	char *challenge, *response;
-
-	debug("Doing skey authentication.");
-
-	/* request a challenge */
-	packet_start(SSH_CMSG_AUTH_TIS);
-	packet_send();
-	packet_write_wait();
-
-	type = packet_read(&payload_len);
-	if (type != SSH_SMSG_FAILURE &&
-	    type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
-		packet_disconnect("Protocol error: got %d in response "
-				  "to skey-auth", type);
-	}
-	if (type != SSH_SMSG_AUTH_TIS_CHALLENGE) {
-		debug("No challenge for skey authentication.");
-		return 0;
-	}
-	challenge = packet_get_string(&clen);
-	packet_integrity_check(payload_len, (4 + clen), type);
-	if (options.cipher == SSH_CIPHER_NONE)
-		log("WARNING: Encryption is disabled! "
-		    "Reponse will be transmitted in clear text.");
-	fprintf(stderr, "%s\n", challenge);
-	xfree(challenge);
-	fflush(stderr);
-	for (i = 0; i < options.number_of_password_prompts; i++) {
-		if (i != 0)
-			error("Permission denied, please try again.");
-		response = read_passphrase("Response: ", 0);
-		packet_start(SSH_CMSG_AUTH_TIS_RESPONSE);
-		packet_put_string(response, strlen(response));
-		memset(response, 0, strlen(response));
-		xfree(response);
-		packet_send();
-		packet_write_wait();
-		type = packet_read(&payload_len);
-		if (type == SSH_SMSG_SUCCESS)
-			return 1;
-		if (type != SSH_SMSG_FAILURE)
-			packet_disconnect("Protocol error: got %d in response "
-					  "to skey-auth-reponse", type);
+		t++;
 	}
-	/* failure */
-	return 0;
-}
+	return s;
 
-/*
- * Tries to authenticate with plain passwd authentication.
- */
-int
-try_password_authentication(char *prompt)
-{
-	int type, i, payload_len;
-	char *password;
-
-	debug("Doing password authentication.");
-	if (options.cipher == SSH_CIPHER_NONE)
-		log("WARNING: Encryption is disabled! Password will be transmitted in clear text.");
-	for (i = 0; i < options.number_of_password_prompts; i++) {
-		if (i != 0)
-			error("Permission denied, please try again.");
-		password = read_passphrase(prompt, 0);
-		packet_start(SSH_CMSG_AUTH_PASSWORD);
-		packet_put_string(password, strlen(password));
-		memset(password, 0, strlen(password));
-		xfree(password);
-		packet_send();
-		packet_write_wait();
-
-		type = packet_read(&payload_len);
-		if (type == SSH_SMSG_SUCCESS)
-			return 1;
-		if (type != SSH_SMSG_FAILURE)
-			packet_disconnect("Protocol error: got %d in response to passwd auth", type);
-	}
-	/* failure */
-	return 0;
 }
 
 /*
@@ -957,7 +320,7 @@ void
 ssh_exchange_identification()
 {
 	char buf[256], remote_version[256];	/* must be same size! */
-	int remote_major, remote_minor, i;
+	int remote_major, remote_minor, i, mismatch;
 	int connection_in = packet_get_connection_in();
 	int connection_out = packet_get_connection_out();
 
@@ -971,7 +334,7 @@ ssh_exchange_identification()
 		if (buf[i] == '\r') {
 			buf[i] = '\n';
 			buf[i + 1] = 0;
-			break;
+			continue;		/**XXX wait for \n */
 		}
 		if (buf[i] == '\n') {
 			buf[i + 1] = 0;
@@ -979,49 +342,73 @@ ssh_exchange_identification()
 		}
 	}
 	buf[sizeof(buf) - 1] = 0;
+	server_version_string = xstrdup(buf);
 
 	/*
 	 * Check that the versions match.  In future this might accept
 	 * several versions and set appropriate flags to handle them.
 	 */
-	if (sscanf(buf, "SSH-%d.%d-%[^\n]\n", &remote_major, &remote_minor,
-		   remote_version) != 3)
+	if (sscanf(server_version_string, "SSH-%d.%d-%[^\n]\n",
+	    &remote_major, &remote_minor, remote_version) != 3)
 		fatal("Bad remote protocol version identification: '%.100s'", buf);
 	debug("Remote protocol version %d.%d, remote software version %.100s",
 	      remote_major, remote_minor, remote_version);
 
-	/* Check if the remote protocol version is too old. */
-	if (remote_major == 1 && remote_minor < 3)
-		fatal("Remote machine has too old SSH software version.");
+	compat_datafellows(remote_version);
+	mismatch = 0;
 
-	/* We speak 1.3, too. */
-	if (remote_major == 1 && remote_minor == 3) {
-		enable_compat13();
-		if (options.forward_agent) {
-			log("Agent forwarding disabled for protocol 1.3");
-			options.forward_agent = 0;
+	switch(remote_major) {
+	case 1:
+		if (remote_minor == 99 &&
+		    (options.protocol & SSH_PROTO_2) &&
+		    !(options.protocol & SSH_PROTO_1_PREFERRED)) {
+			enable_compat20();
+			break;
+		}
+		if (!(options.protocol & SSH_PROTO_1)) {
+			mismatch = 1;
+			break;
+		}
+		if (remote_minor < 3) {
+			fatal("Remote machine has too old SSH software version.");
+		} else if (remote_minor == 3) {
+			/* We speak 1.3, too. */
+			enable_compat13();
+			if (options.forward_agent) {
+				log("Agent forwarding disabled for protocol 1.3");
+				options.forward_agent = 0;
+			}
+		}
+		break;
+	case 2:
+		if (options.protocol & SSH_PROTO_2) {
+			enable_compat20();
+			break;
 		}
+		/* FALLTHROUGH */
+	default:
+		mismatch = 1;
+		break;
 	}
-#if 0
-	/*
-	 * Removed for now, to permit compatibility with latter versions. The
-	 * server will reject our version and disconnect if it doesn't
-	 * support it.
-	 */
-	if (remote_major != PROTOCOL_MAJOR)
+	if (mismatch)
 		fatal("Protocol major versions differ: %d vs. %d",
-		      PROTOCOL_MAJOR, remote_major);
-#endif
-
+		    (options.protocol & SSH_PROTO_2) ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
+		    remote_major);
+	if (compat20)
+		packet_set_ssh2_format();
 	/* Send our own protocol version identification. */
 	snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
-	    PROTOCOL_MAJOR, PROTOCOL_MINOR, SSH_VERSION);
+	    compat20 ? PROTOCOL_MAJOR_2 : PROTOCOL_MAJOR_1,
+	    compat20 ? PROTOCOL_MINOR_2 : PROTOCOL_MINOR_1,
+	    SSH_VERSION);
 	if (atomicio(write, connection_out, buf, strlen(buf)) != strlen(buf))
 		fatal("write: %.100s", strerror(errno));
+	client_version_string = xstrdup(buf);
+	chop(client_version_string);
+	chop(server_version_string);
+	debug("Local version string %.100s", client_version_string);
 }
 
-int ssh_cipher_default = SSH_CIPHER_3DES;
-
 int
 read_yes_or_no(const char *prompt, int defval)
 {
@@ -1070,9 +457,11 @@ read_yes_or_no(const char *prompt, int defval)
  */
 
 void
-check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
+check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key,
+	const char *user_hostfile, const char *system_hostfile)
 {
 	Key *file_key;
+	char *type = key_type(host_key);
 	char *ip = NULL;
 	char hostline[1000], *hostp;
 	HostStatus host_status;
@@ -1088,6 +477,7 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 	 * essentially disables host authentication for localhost; however,
 	 * this is probably not a real problem.
 	 */
+	/**  hostaddr == 0! */
 	switch (hostaddr->sa_family) {
 	case AF_INET:
 		local = (ntohl(((struct sockaddr_in *)hostaddr)->sin_addr.s_addr) >> 24) == IN_LOOPBACKNET;
@@ -1128,19 +518,19 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 	 * Check if the host key is present in the user\'s list of known
 	 * hosts or in the systemwide list.
 	 */
-	host_status = check_host_in_hostfile(options.user_hostfile, host, host_key, file_key);
+	host_status = check_host_in_hostfile(user_hostfile, host, host_key, file_key);
 	if (host_status == HOST_NEW)
-		host_status = check_host_in_hostfile(options.system_hostfile, host, host_key, file_key);
+		host_status = check_host_in_hostfile(system_hostfile, host, host_key, file_key);
 	/*
 	 * Also perform check for the ip address, skip the check if we are
 	 * localhost or the hostname was an ip address to begin with
 	 */
 	if (options.check_host_ip && !local && strcmp(host, ip)) {
 		Key *ip_key = key_new(host_key->type);
-		ip_status = check_host_in_hostfile(options.user_hostfile, ip, host_key, ip_key);
+		ip_status = check_host_in_hostfile(user_hostfile, ip, host_key, ip_key);
 
 		if (ip_status == HOST_NEW)
-			ip_status = check_host_in_hostfile(options.system_hostfile, ip, host_key, ip_key);
+			ip_status = check_host_in_hostfile(system_hostfile, ip, host_key, ip_key);
 		if (host_status == HOST_CHANGED &&
 		    (ip_status != HOST_CHANGED || !key_equal(ip_key, file_key)))
 			host_ip_differ = 1;
@@ -1154,18 +544,19 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 	switch (host_status) {
 	case HOST_OK:
 		/* The host is known and the key matches. */
-		debug("Host '%.200s' is known and matches the host key.", host);
+		debug("Host '%.200s' is known and matches the %s host key.",
+		    host, type);
 		if (options.check_host_ip) {
 			if (ip_status == HOST_NEW) {
-				if (!add_host_to_hostfile(options.user_hostfile, ip, host_key))
-					log("Failed to add the host key for IP address '%.30s' to the list of known hosts (%.30s).",
-					    ip, options.user_hostfile);
+				if (!add_host_to_hostfile(user_hostfile, ip, host_key))
+					log("Failed to add the %s host key for IP address '%.30s' to the list of known hosts (%.30s).",
+					    type, ip, user_hostfile);
 				else
-					log("Warning: Permanently added host key for IP address '%.30s' to the list of known hosts.",
-					    ip);
+					log("Warning: Permanently added the %s host key for IP address '%.30s' to the list of known hosts.",
+					    type, ip);
 			} else if (ip_status != HOST_OK)
-				log("Warning: the host key for '%.200s' differs from the key for the IP address '%.30s'",
-				    host, ip);
+				log("Warning: the %s host key for '%.200s' differs from the key for the IP address '%.30s'",
+				    type, host, ip);
 		}
 		break;
 	case HOST_NEW:
@@ -1173,16 +564,16 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 		if (options.strict_host_key_checking == 1) {
 			/* User has requested strict host key checking.  We will not add the host key
 			   automatically.  The only alternative left is to abort. */
-			fatal("No host key is known for %.200s and you have requested strict checking.", host);
+			fatal("No %s host key is known for %.200s and you have requested strict checking.", type, host);
 		} else if (options.strict_host_key_checking == 2) {
 			/* The default */
 			char prompt[1024];
 			char *fp = key_fingerprint(host_key);
 			snprintf(prompt, sizeof(prompt),
 			    "The authenticity of host '%.200s' can't be established.\n"
-			    "Key fingerprint is %s.\n"
+			    "%s key fingerprint is %s.\n"
 			    "Are you sure you want to continue connecting (yes/no)? ",
-			    host, fp);
+			    host, type, fp);
 			if (!read_yes_or_no(prompt, -1))
 				fatal("Aborted by user!\n");
 		}
@@ -1193,12 +584,12 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 			hostp = host;
 
 		/* If not in strict mode, add the key automatically to the local known_hosts file. */
-		if (!add_host_to_hostfile(options.user_hostfile, hostp, host_key))
+		if (!add_host_to_hostfile(user_hostfile, hostp, host_key))
 			log("Failed to add the host to the list of known hosts (%.500s).",
-			    options.user_hostfile);
+			    user_hostfile);
 		else
-			log("Warning: Permanently added '%.200s' to the list of known hosts.",
-			    hostp);
+			log("Warning: Permanently added '%.200s' (%s) to the list of known hosts.",
+			    hostp, type);
 		break;
 	case HOST_CHANGED:
 		if (options.check_host_ip && host_ip_differ) {
@@ -1212,7 +603,7 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 			error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
 			error("@       WARNING: POSSIBLE DNS SPOOFING DETECTED!          @");
 			error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
-			error("The host key for %s has changed,", host);
+			error("The %s host key for %s has changed,", type, host);
 			error("and the key for the according IP address %s", ip);
 			error("%s. This could either mean that", msg);
 			error("DNS SPOOFING is happening or the IP address for the host");
@@ -1224,17 +615,17 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 		error("@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@");
 		error("IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!");
 		error("Someone could be eavesdropping on you right now (man-in-the-middle attack)!");
-		error("It is also possible that the host key has just been changed.");
+		error("It is also possible that the %s host key has just been changed.", type);
 		error("Please contact your system administrator.");
 		error("Add correct host key in %.100s to get rid of this message.",
-		      options.user_hostfile);
+		      user_hostfile);
 
 		/*
 		 * If strict host key checking is in use, the user will have
 		 * to edit the key manually and we can only abort.
 		 */
 		if (options.strict_host_key_checking)
-			fatal("Host key for %.200s has changed and you have requested strict checking.", host);
+			fatal("%s host key for %.200s has changed and you have requested strict checking.", type, host);
 
 		/*
 		 * If strict host key checking has not been requested, allow
@@ -1261,349 +652,8 @@ check_host_key(char *host, struct sockaddr *hostaddr, Key *host_key)
 	if (options.check_host_ip)
 		xfree(ip);
 }
-void
-check_rsa_host_key(char *host, struct sockaddr *hostaddr, RSA *host_key)
-{
-	Key k;
-	k.type = KEY_RSA;
-	k.rsa = host_key;
-	check_host_key(host, hostaddr, &k);
-}
-
-/*
- * SSH1 key exchange
- */
-void
-ssh_kex(char *host, struct sockaddr *hostaddr)
-{
-	int i;
-	BIGNUM *key;
-	RSA *host_key;
-	RSA *public_key;
-	int bits, rbits;
-	unsigned char session_key[SSH_SESSION_KEY_LENGTH];
-	unsigned char cookie[8];
-	unsigned int supported_ciphers;
-	unsigned int server_flags, client_flags;
-	int payload_len, clen, sum_len = 0;
-	u_int32_t rand = 0;
-
-	debug("Waiting for server public key.");
-
-	/* Wait for a public key packet from the server. */
-	packet_read_expect(&payload_len, SSH_SMSG_PUBLIC_KEY);
-
-	/* Get cookie from the packet. */
-	for (i = 0; i < 8; i++)
-		cookie[i] = packet_get_char();
-
-	/* Get the public key. */
-	public_key = RSA_new();
-	bits = packet_get_int();/* bits */
-	public_key->e = BN_new();
-	packet_get_bignum(public_key->e, &clen);
-	sum_len += clen;
-	public_key->n = BN_new();
-	packet_get_bignum(public_key->n, &clen);
-	sum_len += clen;
-
-	rbits = BN_num_bits(public_key->n);
-	if (bits != rbits) {
-		log("Warning: Server lies about size of server public key: "
-		    "actual size is %d bits vs. announced %d.", rbits, bits);
-		log("Warning: This may be due to an old implementation of ssh.");
-	}
-	/* Get the host key. */
-	host_key = RSA_new();
-	bits = packet_get_int();/* bits */
-	host_key->e = BN_new();
-	packet_get_bignum(host_key->e, &clen);
-	sum_len += clen;
-	host_key->n = BN_new();
-	packet_get_bignum(host_key->n, &clen);
-	sum_len += clen;
-
-	rbits = BN_num_bits(host_key->n);
-	if (bits != rbits) {
-		log("Warning: Server lies about size of server host key: "
-		    "actual size is %d bits vs. announced %d.", rbits, bits);
-		log("Warning: This may be due to an old implementation of ssh.");
-	}
-
-	/* Get protocol flags. */
-	server_flags = packet_get_int();
-	packet_set_protocol_flags(server_flags);
-
-	supported_ciphers = packet_get_int();
-	supported_authentications = packet_get_int();
-
-	debug("Received server public key (%d bits) and host key (%d bits).",
-	      BN_num_bits(public_key->n), BN_num_bits(host_key->n));
-
-	packet_integrity_check(payload_len,
-			       8 + 4 + sum_len + 0 + 4 + 0 + 0 + 4 + 4 + 4,
-			       SSH_SMSG_PUBLIC_KEY);
-
-	check_rsa_host_key(host, hostaddr, host_key);
-
-	client_flags = SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN;
-
-	compute_session_id(session_id, cookie, host_key->n, public_key->n);
-
-	/* Generate a session key. */
-	arc4random_stir();
-
-	/*
-	 * Generate an encryption key for the session.   The key is a 256 bit
-	 * random number, interpreted as a 32-byte key, with the least
-	 * significant 8 bits being the first byte of the key.
-	 */
-	for (i = 0; i < 32; i++) {
-		if (i % 4 == 0)
-			rand = arc4random();
-		session_key[i] = rand & 0xff;
-		rand >>= 8;
-	}
-
-	/*
-	 * According to the protocol spec, the first byte of the session key
-	 * is the highest byte of the integer.  The session key is xored with
-	 * the first 16 bytes of the session id.
-	 */
-	key = BN_new();
-	BN_set_word(key, 0);
-	for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) {
-		BN_lshift(key, key, 8);
-		if (i < 16)
-			BN_add_word(key, session_key[i] ^ session_id[i]);
-		else
-			BN_add_word(key, session_key[i]);
-	}
-
-	/*
-	 * Encrypt the integer using the public key and host key of the
-	 * server (key with smaller modulus first).
-	 */
-	if (BN_cmp(public_key->n, host_key->n) < 0) {
-		/* Public key has smaller modulus. */
-		if (BN_num_bits(host_key->n) <
-		    BN_num_bits(public_key->n) + SSH_KEY_BITS_RESERVED) {
-			fatal("respond_to_rsa_challenge: host_key %d < public_key %d + "
-			      "SSH_KEY_BITS_RESERVED %d",
-			      BN_num_bits(host_key->n),
-			      BN_num_bits(public_key->n),
-			      SSH_KEY_BITS_RESERVED);
-		}
-		rsa_public_encrypt(key, key, public_key);
-		rsa_public_encrypt(key, key, host_key);
-	} else {
-		/* Host key has smaller modulus (or they are equal). */
-		if (BN_num_bits(public_key->n) <
-		    BN_num_bits(host_key->n) + SSH_KEY_BITS_RESERVED) {
-			fatal("respond_to_rsa_challenge: public_key %d < host_key %d + "
-			      "SSH_KEY_BITS_RESERVED %d",
-			      BN_num_bits(public_key->n),
-			      BN_num_bits(host_key->n),
-			      SSH_KEY_BITS_RESERVED);
-		}
-		rsa_public_encrypt(key, key, host_key);
-		rsa_public_encrypt(key, key, public_key);
-	}
-
-	/* Destroy the public keys since we no longer need them. */
-	RSA_free(public_key);
-	RSA_free(host_key);
-
-	if (options.cipher == SSH_CIPHER_NOT_SET) {
-		if (cipher_mask() & supported_ciphers & (1 << ssh_cipher_default))
-			options.cipher = ssh_cipher_default;
-		else {
-			debug("Cipher %s not supported, using %.100s instead.",
-			      cipher_name(ssh_cipher_default),
-			      cipher_name(SSH_FALLBACK_CIPHER));
-			options.cipher = SSH_FALLBACK_CIPHER;
-		}
-	}
-	/* Check that the selected cipher is supported. */
-	if (!(supported_ciphers & (1 << options.cipher)))
-		fatal("Selected cipher type %.100s not supported by server.",
-		      cipher_name(options.cipher));
-
-	debug("Encryption type: %.100s", cipher_name(options.cipher));
-
-	/* Send the encrypted session key to the server. */
-	packet_start(SSH_CMSG_SESSION_KEY);
-	packet_put_char(options.cipher);
-
-	/* Send the cookie back to the server. */
-	for (i = 0; i < 8; i++)
-		packet_put_char(cookie[i]);
-
-	/* Send and destroy the encrypted encryption key integer. */
-	packet_put_bignum(key);
-	BN_clear_free(key);
-
-	/* Send protocol flags. */
-	packet_put_int(client_flags);
-
-	/* Send the packet now. */
-	packet_send();
-	packet_write_wait();
-
-	debug("Sent encrypted session key.");
-
-	/* Set the encryption key. */
-	packet_set_encryption_key(session_key, SSH_SESSION_KEY_LENGTH, options.cipher);
-
-	/* We will no longer need the session key here.  Destroy any extra copies. */
-	memset(session_key, 0, sizeof(session_key));
-
-	/*
-	 * Expect a success message from the server.  Note that this message
-	 * will be received in encrypted form.
-	 */
-	packet_read_expect(&payload_len, SSH_SMSG_SUCCESS);
-
-	debug("Received encrypted confirmation.");
-}
 
 /*
- * Authenticate user
- */
-void
-ssh_userauth(int host_key_valid, RSA *own_host_key,
-    uid_t original_real_uid, char *host)
-{
-	int i, type;
-	int payload_len;
-	struct passwd *pw;
-	const char *server_user, *local_user;
-
-	/* Get local user name.  Use it as server user if no user name was given. */
-	pw = getpwuid(original_real_uid);
-	if (!pw)
-		fatal("User id %d not found from user database.", original_real_uid);
-	local_user = xstrdup(pw->pw_name);
-	server_user = options.user ? options.user : local_user;
-
-	/* Send the name of the user to log in as on the server. */
-	packet_start(SSH_CMSG_USER);
-	packet_put_string(server_user, strlen(server_user));
-	packet_send();
-	packet_write_wait();
-
-	/*
-	 * The server should respond with success if no authentication is
-	 * needed (the user has no password).  Otherwise the server responds
-	 * with failure.
-	 */
-	type = packet_read(&payload_len);
-
-	/* check whether the connection was accepted without authentication. */
-	if (type == SSH_SMSG_SUCCESS)
-		return;
-	if (type != SSH_SMSG_FAILURE)
-		packet_disconnect("Protocol error: got %d in response to SSH_CMSG_USER",
-				  type);
-
-#ifdef AFS
-	/* Try Kerberos tgt passing if the server supports it. */
-	if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) &&
-	    options.kerberos_tgt_passing) {
-		if (options.cipher == SSH_CIPHER_NONE)
-			log("WARNING: Encryption is disabled! Ticket will be transmitted in the clear!");
-		(void) send_kerberos_tgt();
-	}
-	/* Try AFS token passing if the server supports it. */
-	if ((supported_authentications & (1 << SSH_PASS_AFS_TOKEN)) &&
-	    options.afs_token_passing && k_hasafs()) {
-		if (options.cipher == SSH_CIPHER_NONE)
-			log("WARNING: Encryption is disabled! Token will be transmitted in the clear!");
-		send_afs_tokens();
-	}
-#endif /* AFS */
-
-#ifdef KRB4
-	if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) &&
-	    options.kerberos_authentication) {
-		debug("Trying Kerberos authentication.");
-		if (try_kerberos_authentication()) {
-			/* The server should respond with success or failure. */
-			type = packet_read(&payload_len);
-			if (type == SSH_SMSG_SUCCESS)
-				return;
-			if (type != SSH_SMSG_FAILURE)
-				packet_disconnect("Protocol error: got %d in response to Kerberos auth", type);
-		}
-	}
-#endif /* KRB4 */
-
-	/*
-	 * Use rhosts authentication if running in privileged socket and we
-	 * do not wish to remain anonymous.
-	 */
-	if ((supported_authentications & (1 << SSH_AUTH_RHOSTS)) &&
-	    options.rhosts_authentication) {
-		debug("Trying rhosts authentication.");
-		packet_start(SSH_CMSG_AUTH_RHOSTS);
-		packet_put_string(local_user, strlen(local_user));
-		packet_send();
-		packet_write_wait();
-
-		/* The server should respond with success or failure. */
-		type = packet_read(&payload_len);
-		if (type == SSH_SMSG_SUCCESS)
-			return;
-		if (type != SSH_SMSG_FAILURE)
-			packet_disconnect("Protocol error: got %d in response to rhosts auth",
-					  type);
-	}
-	/*
-	 * Try .rhosts or /etc/hosts.equiv authentication with RSA host
-	 * authentication.
-	 */
-	if ((supported_authentications & (1 << SSH_AUTH_RHOSTS_RSA)) &&
-	    options.rhosts_rsa_authentication && host_key_valid) {
-		if (try_rhosts_rsa_authentication(local_user, own_host_key))
-			return;
-	}
-	/* Try RSA authentication if the server supports it. */
-	if ((supported_authentications & (1 << SSH_AUTH_RSA)) &&
-	    options.rsa_authentication) {
-		/*
-		 * Try RSA authentication using the authentication agent. The
-		 * agent is tried first because no passphrase is needed for
-		 * it, whereas identity files may require passphrases.
-		 */
-		if (try_agent_authentication())
-			return;
-
-		/* Try RSA authentication for each identity. */
-		for (i = 0; i < options.num_identity_files; i++)
-			if (try_rsa_authentication(options.identity_files[i]))
-				return;
-	}
-	/* Try skey authentication if the server supports it. */
-	if ((supported_authentications & (1 << SSH_AUTH_TIS)) &&
-	    options.skey_authentication && !options.batch_mode) {
-		if (try_skey_authentication())
-			return;
-	}
-	/* Try password authentication if the server supports it. */
-	if ((supported_authentications & (1 << SSH_AUTH_PASSWORD)) &&
-	    options.password_authentication && !options.batch_mode) {
-		char prompt[80];
-
-		snprintf(prompt, sizeof(prompt), "%.30s@%.40s's password: ",
-		    server_user, host);
-		if (try_password_authentication(prompt))
-			return;
-	}
-	/* All authentication methods have failed.  Exit with an error message. */
-	fatal("Permission denied.");
-	/* NOTREACHED */
-}
-/*
  * Starts a dialog with the server, and authenticates the current user on the
  * server.  This does not need any extra privileges.  The basic connection
  * to the server must already have been established before this is called.
@@ -1614,7 +664,16 @@ void
 ssh_login(int host_key_valid, RSA *own_host_key, const char *orighost,
     struct sockaddr *hostaddr, uid_t original_real_uid)
 {
+	struct passwd *pw;
 	char *host, *cp;
+	char *server_user, *local_user;
+
+	/* Get local user name.  Use it as server user if no user name was given. */
+	pw = getpwuid(original_real_uid);
+	if (!pw)
+		fatal("User id %d not found from user database.", original_real_uid);
+	local_user = xstrdup(pw->pw_name);
+	server_user = options.user ? options.user : local_user;
 
 	/* Convert the user-supplied hostname into all lowercase. */
 	host = xstrdup(orighost);
@@ -1628,12 +687,13 @@ ssh_login(int host_key_valid, RSA *own_host_key, const char *orighost,
 	/* Put the connection into non-blocking mode. */
 	packet_set_nonblocking();
 
-	supported_authentications = 0;
 	/* key exchange */
-	ssh_kex(host, hostaddr);
-	if (supported_authentications == 0)
-		fatal("supported_authentications == 0.");
-
 	/* authenticate user */
-	ssh_userauth(host_key_valid, own_host_key, original_real_uid, host);
+	if (compat20) {
+		ssh_kex2(host, hostaddr);
+		ssh_userauth2(server_user, host);
+	} else {
+		ssh_kex(host, hostaddr);
+		ssh_userauth(local_user, server_user, host, host_key_valid, own_host_key);
+	}
 }