- OpenBSD CVS updates:

   - [channels.c]
     repair x11-fwd
   - [sshconnect.c]
     fix passwd prompt for ssh2, less debugging output.
   - [clientloop.c compat.c dsa.c kex.c sshd.c]
     less debugging output
   - [kex.c kex.h sshconnect.c sshd.c]
     check for reasonable public DH values
   - [README.openssh2 cipher.c cipher.h compat.c compat.h readconf.c]
     [readconf.h servconf.c servconf.h ssh.c ssh.h sshconnect.c sshd.c]
     add Cipher and Protocol options to ssh/sshd, e.g.:
     ssh -o 'Protocol 1,2' if you prefer proto 1, ssh -o 'Ciphers
     arcfour,3des-cbc'
   - [sshd.c]
     print 1.99 only if server supports both

19 files changed, 363 insertions, 145 deletions

diff --git a/ChangeLog b/ChangeLog
index 976c3834f..af54ab6d8 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,21 @@
+20000412
+ - OpenBSD CVS updates:
+   - [channels.c]
+     repair x11-fwd
+   - [sshconnect.c]
+     fix passwd prompt for ssh2, less debugging output.
+   - [clientloop.c compat.c dsa.c kex.c sshd.c]
+     less debugging output
+   - [kex.c kex.h sshconnect.c sshd.c]
+     check for reasonable public DH values
+   - [README.openssh2 cipher.c cipher.h compat.c compat.h readconf.c]
+     [readconf.h servconf.c servconf.h ssh.c ssh.h sshconnect.c sshd.c]
+     add Cipher and Protocol options to ssh/sshd, e.g.:
+     ssh -o 'Protocol 1,2' if you prefer proto 1, ssh -o 'Ciphers
+     arcfour,3des-cbc'
+   - [sshd.c]
+     print 1.99 only if server supports both
+
 20000408
  - Avoid some compiler warnings in fake-get*.c
  - Add IPTOS macros for systems which lack them
diff --git a/README.openssh2 b/README.openssh2
index 59f8cf9f6..bdf78bf58 100644
--- a/README.openssh2
+++ b/README.openssh2
@@ -1,4 +1,13 @@
-$Id: README.openssh2,v 1.2 2000/04/06 21:28:22 markus Exp $
+$Id: README.openssh2,v 1.3 2000/04/12 07:45:43 markus Exp $
+
+howto:
+        1) generate server key:
+                $ umask 077
+                $ openssl dsaparam 1024 -out dsa1024.pem
+                $ openssl gendsa -out /etc/ssh_dsa_key dsa1024.pem -rand /dev/arandom
+        2) enable ssh2:
+                server: add 'Protocol 2,1' to /etc/sshd_config
+                client: ssh -o 'Protocol 2,1', or add to .ssh/config
 
 works:
         secsh-transport: works w/o rekey
@@ -11,11 +20,7 @@ works:
                 tcp-forwarding: -L works
         dss: verification works,
                 key database in ~/.ssh/known_hosts with bits == 0 hack
-        dss: signature works, keygen w/ openssl:
-                $ umask 077
-                $ openssl dsaparam 1024 -out dsa1024.pem
-                $ openssl gendsa -out /etc/ssh_dsa_key dsa1024.pem -rand /dev/arandom
-                start sshd with '-2' flag
+        dss: signature works, keygen w/ openssl
         client interops w/ sshd2, lshd
         server interops w/ ssh2, lsh, ssh.com's Windows client, SecureCRT
         server supports multiple concurrent sessions (e.g. with SSH.com Windows client)
@@ -33,4 +38,4 @@ todo:
         sftp
 
 -markus
-$Date: 2000/04/06 21:28:22 $
+$Date: 2000/04/12 07:45:43 $
diff --git a/channels.c b/channels.c
index c140b77dc..957b4a428 100644
--- a/channels.c
+++ b/channels.c
@@ -17,7 +17,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: channels.c,v 1.23 2000/04/12 08:45:06 damien Exp $");
+RCSID("$Id: channels.c,v 1.24 2000/04/12 10:17:38 damien Exp $");
 
 #include "ssh.h"
 #include "packet.h"
@@ -437,6 +437,7 @@ channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
         if (ret == 1) {
                 /* Start normal processing for the channel. */
                 c->type = SSH_CHANNEL_OPEN;
+                channel_pre_open_13(c, readset, writeset);
         } else if (ret == -1) {
                 /*
                  * We have received an X11 connection that has bad
@@ -460,6 +461,7 @@ channel_pre_x11_open_15(Channel *c, fd_set * readset, fd_set * writeset)
         int ret = x11_open_helper(c);
         if (ret == 1) {
                 c->type = SSH_CHANNEL_OPEN;
+                channel_pre_open_15(c, readset, writeset);
         } else if (ret == -1) {
                 debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
                 chan_read_failed(c);
diff --git a/cipher.c b/cipher.c
index 8911ffef6..27debf90f 100644
--- a/cipher.c
+++ b/cipher.c
@@ -12,11 +12,11 @@
  */
 
 #include "includes.h"
-RCSID("$Id: cipher.c,v 1.16 2000/04/06 02:32:39 damien Exp $");
+RCSID("$Id: cipher.c,v 1.17 2000/04/12 10:17:39 damien Exp $");
 
 #include "ssh.h"
 #include "cipher.h"
-#include "config.h"
+#include "xmalloc.h"
 
 #ifdef HAVE_OPENSSL
 #include <openssl/md5.h>
@@ -26,7 +26,9 @@ RCSID("$Id: cipher.c,v 1.16 2000/04/06 02:32:39 damien Exp $");
 #endif
 
 /*
- * What kind of tripple DES are these 2 routines?
+ * This is used by SSH1:
+ *
+ * What kind of triple DES are these 2 routines?
  *
  * Why is there a redundant initialization vector?
  *
@@ -81,7 +83,7 @@ SSH_3CBC_DECRYPT(des_key_schedule ks1,
 }
 
 /*
- * SSH uses a variation on Blowfish, all bytes must be swapped before
+ * SSH1 uses a variation on Blowfish, all bytes must be swapped before
  * and after encryption/decryption. Thus the swap_bytes stuff (yuk).
  */
 static void
@@ -167,10 +169,34 @@ cipher_name(int cipher)
 {
         if (cipher < 0 || cipher >= sizeof(cipher_names) / sizeof(cipher_names[0]) ||
             cipher_names[cipher] == NULL)
-                fatal("cipher_name: bad cipher number: %d", cipher);
+                fatal("cipher_name: bad cipher name: %d", cipher);
         return cipher_names[cipher];
 }
 
+/* Returns 1 if the name of the ciphers are valid. */
+
+#define CIPHER_SEP      ","
+int
+ciphers_valid(const char *names)
+{
+        char *ciphers;
+        char *p;
+        int i;
+
+        if (strcmp(names, "") == 0)
+                return 0;
+        ciphers = xstrdup(names);
+        for ((p = strtok(ciphers, CIPHER_SEP)); p; (p = strtok(NULL, CIPHER_SEP))) {
+                i = cipher_number(p);
+                if (i == -1 || !(cipher_mask2() & (1 << i))) {
+                        xfree(ciphers);
+                        return 0;
+                }
+        }
+        xfree(ciphers);
+        return 1;
+}
+
 /*
  * Parses the name of the cipher.  Returns the number of the corresponding
  * cipher, or -1 on error.
@@ -271,7 +297,6 @@ cipher_set_key(CipherContext *context, int cipher, const unsigned char *key,
         memset(padded, 0, sizeof(padded));
 }
 
-
 void 
 cipher_set_key_iv(CipherContext * context, int cipher,
     const unsigned char *key, int keylen, 
diff --git a/cipher.h b/cipher.h
index 94c0ceee5..ee0e312fb 100644
--- a/cipher.h
+++ b/cipher.h
@@ -11,7 +11,7 @@
  * 
  */
 
-/* RCSID("$Id: cipher.h,v 1.8 2000/04/06 02:32:39 damien Exp $"); */
+/* RCSID("$Id: cipher.h,v 1.9 2000/04/12 10:17:39 damien Exp $"); */
 
 #ifndef CIPHER_H
 #define CIPHER_H
@@ -88,6 +88,9 @@ const char *cipher_name(int cipher);
  */
 int     cipher_number(const char *name);
 
+/* returns 1 if all ciphers are supported (ssh2 only) */
+int     ciphers_valid(const char *names);
+
 /*
  * Selects the cipher to use and sets the key.  If for_encryption is true,
  * the key is setup for encryption; otherwise it is setup for decryption.
diff --git a/clientloop.c b/clientloop.c
index 4f2e5037d..91a200663 100644
--- a/clientloop.c
+++ b/clientloop.c
@@ -16,7 +16,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: clientloop.c,v 1.9 2000/04/06 02:32:39 damien Exp $");
+RCSID("$Id: clientloop.c,v 1.10 2000/04/12 10:17:39 damien Exp $");
 
 #include "xmalloc.h"
 #include "ssh.h"
@@ -1013,7 +1013,7 @@ client_input_channel_req(int id, void *arg)
         rtype = packet_get_string(&len);
         reply = packet_get_char();
 
-        log("session_input_channel_req: rtype %s reply %d", rtype, reply);
+        debug("session_input_channel_req: rtype %s reply %d", rtype, reply);
 
         c = channel_lookup(id);
         if (c == NULL)
diff --git a/compat.c b/compat.c
index c183866c3..d56e3e81d 100644
--- a/compat.c
+++ b/compat.c
@@ -28,10 +28,12 @@
  */
 
 #include "includes.h"
-RCSID("$Id: compat.c,v 1.6 2000/04/12 08:45:06 damien Exp $");
+RCSID("$Id: compat.c,v 1.7 2000/04/12 10:17:39 damien Exp $");
 
 #include "ssh.h"
 #include "packet.h"
+#include "xmalloc.h"
+#include "compat.h"
 
 int compat13 = 0;
 int compat20 = 0;
@@ -65,9 +67,36 @@ compat_datafellows(const char *version)
                 len = strlen(check[i]);
                 if (strlen(version) >= len &&
                    (strncmp(version, check[i], len) == 0)) {
-                        log("datafellows: %.200s", version);
+                        verbose("datafellows: %.200s", version);
                         datafellows = 1;
                         return;
                 }
         }
 }
+
+#define SEP     ","
+int
+proto_spec(const char *spec)
+{
+        char *s = xstrdup(spec);
+        char *p;
+        int ret = SSH_PROTO_UNKNOWN;
+
+        for ((p = strtok(s, SEP)); p; (p = strtok(NULL, SEP))) {
+                switch(atoi(p)) {
+                case 1:
+                        if (ret == SSH_PROTO_UNKNOWN)
+                                ret |= SSH_PROTO_1_PREFERRED;
+                        ret |= SSH_PROTO_1;
+                        break;
+                case 2:
+                        ret |= SSH_PROTO_2;
+                        break;
+                default:
+                        log("ignoring bad proto spec: '%s'.", p);
+                        break;
+                }
+        }
+        xfree(s);
+        return ret;
+}
diff --git a/compat.h b/compat.h
index 4247f53b4..4943e5a29 100644
--- a/compat.h
+++ b/compat.h
@@ -26,13 +26,20 @@
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
-/* RCSID("$Id: compat.h,v 1.4 2000/04/04 04:39:01 damien Exp $"); */
+/* RCSID("$Id: compat.h,v 1.5 2000/04/12 10:17:39 damien Exp $"); */
 
 #ifndef COMPAT_H
 #define COMPAT_H
+
+#define SSH_PROTO_UNKNOWN       0x00
+#define SSH_PROTO_1             0x01
+#define SSH_PROTO_1_PREFERRED   0x02
+#define SSH_PROTO_2             0x04
+
 void    enable_compat13(void);
 void    enable_compat20(void);
 void    compat_datafellows(const char *s);
+int     proto_spec(const char *spec);
 extern int compat13;
 extern int compat20;
 extern int datafellows;
diff --git a/dsa.c b/dsa.c
index eeb4ead10..a35d85bf5 100644
--- a/dsa.c
+++ b/dsa.c
@@ -28,7 +28,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: dsa.c,v 1.1 2000/04/04 04:39:01 damien Exp $");
+RCSID("$Id: dsa.c,v 1.2 2000/04/12 06:37:02 markus Exp $");
 
 #include "ssh.h"
 #include "xmalloc.h"
@@ -80,7 +80,7 @@ dsa_serverkey_from_blob(
         buffer_append(&b, serverhostkey, serverhostkeylen);
         ktype = buffer_get_string(&b, NULL);
         if (strcmp(KEX_DSS, ktype) != 0) {
-                log("dsa_serverkey_from_blob: cannot handle type  %s", ktype);
+                error("dsa_serverkey_from_blob: cannot handle type  %s", ktype);
                 key_free(key);
                 return NULL;
         }
@@ -90,10 +90,10 @@ dsa_serverkey_from_blob(
         buffer_get_bignum2(&b, dsa->pub_key);
         rlen = buffer_len(&b);
         if(rlen != 0)
-                log("dsa_serverkey_from_blob: remaining bytes in serverhostkey %d", rlen);
+                error("dsa_serverkey_from_blob: remaining bytes in serverhostkey %d", rlen);
         buffer_free(&b);
 
-        log("keytype %s", ktype);
+        debug("keytype %s", ktype);
 #ifdef DEBUG_DSS
         DSA_print_fp(stderr, dsa, 8);
 #endif
@@ -172,7 +172,7 @@ dsa_sign(
         Buffer b;
 
         if (key == NULL || key->type != KEY_DSA || key->dsa == NULL) {
-                log("dsa_sign: no DSA key");
+                error("dsa_sign: no DSA key");
                 return -1;
         }
         digest = xmalloc(evp_md->md_size);
@@ -185,11 +185,11 @@ dsa_sign(
         rlen = BN_num_bytes(sig->r);
         slen = BN_num_bytes(sig->s);
         if (rlen > INTBLOB_LEN || slen > INTBLOB_LEN) {
-                log("bad sig size %d %d", rlen, slen);
+                error("bad sig size %d %d", rlen, slen);
                 DSA_SIG_free(sig);
                 return -1;
         }
-        log("sig size %d %d", rlen, slen);
+        debug("sig size %d %d", rlen, slen);
 
         memset(sigblob, 0, SIGBLOB_LEN);
         BN_bn2bin(sig->r, sigblob+ SIGBLOB_LEN - INTBLOB_LEN - rlen);
@@ -197,7 +197,7 @@ dsa_sign(
         DSA_SIG_free(sig);
 
         if (datafellows) {
-                log("datafellows");
+                debug("datafellows");
                 ret = xmalloc(SIGBLOB_LEN);
                 memcpy(ret, sigblob, SIGBLOB_LEN);
                 if (lenp != NULL)
@@ -239,7 +239,7 @@ dsa_verify(
         int ret;
 
         if (key == NULL || key->type != KEY_DSA || key->dsa == NULL) {
-                log("dsa_verify: no DSA key");
+                error("dsa_verify: no DSA key");
                 return -1;
         }
 
@@ -248,7 +248,7 @@ dsa_verify(
                 datafellows = 0;
         }
 
-        log("len %d datafellows %d", signaturelen, datafellows);
+        debug("len %d datafellows %d", signaturelen, datafellows);
 
         /* fetch signature */
         if (datafellows) {
@@ -262,7 +262,7 @@ dsa_verify(
                 sigblob = (unsigned char *)buffer_get_string(&b, &len);
                 rlen = buffer_len(&b);
                 if(rlen != 0)
-                        log("remaining bytes in signature %d", rlen);
+                        error("remaining bytes in signature %d", rlen);
                 buffer_free(&b);
         }
 
@@ -305,6 +305,6 @@ dsa_verify(
                 txt = "error";
                 break;
         }
-        log("dsa_verify: signature %s", txt);
+        debug("dsa_verify: signature %s", txt);
         return ret;
 }
diff --git a/kex.c b/kex.c
index d2047d6f1..9ec75ee0e 100644
--- a/kex.c
+++ b/kex.c
@@ -28,7 +28,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: kex.c,v 1.2 2000/04/04 04:57:08 damien Exp $");
+RCSID("$Id: kex.c,v 1.3 2000/04/12 10:17:39 damien Exp $");
 
 #include "ssh.h"
 #include "ssh2.h"
@@ -43,8 +43,6 @@ RCSID("$Id: kex.c,v 1.2 2000/04/04 04:57:08 damien Exp $");
 # include <openssl/dh.h>
 # include <openssl/crypto.h>
 # include <openssl/bio.h>
-# include <openssl/bn.h>
-# include <openssl/dh.h>
 # include <openssl/pem.h>
 #endif /* HAVE_OPENSSL */
 #if HAVE_SSL
@@ -52,12 +50,9 @@ RCSID("$Id: kex.c,v 1.2 2000/04/04 04:57:08 damien Exp $");
 # include <ssl/dh.h>
 # include <ssl/crypto.h>
 # include <ssl/bio.h>
-# include <ssl/bn.h>
-# include <ssl/dh.h>
 # include <ssl/pem.h>
 #endif /* HAVE_SSL */
 
-#include "entropy.h"
 #include "kex.h"
 
 Buffer *
@@ -85,8 +80,36 @@ kex_init(char *myproposal[PROPOSAL_MAX])
 
 /* diffie-hellman-group1-sha1 */
 
+int
+dh_pub_is_valid(DH *dh, BIGNUM *dh_pub)
+{
+        int i;
+        int n = BN_num_bits(dh_pub);
+        int bits_set = 0;
+
+        /* we only accept g==2 */
+        if (!BN_is_word(dh->g, 2)) {
+                log("invalid DH base != 2");
+                return 0;
+        }
+        if (dh_pub->neg) {
+                log("invalid public DH value: negativ");
+                return 0;
+        }
+        for (i = 0; i <= n; i++)
+                if (BN_is_bit_set(dh_pub, i))
+                        bits_set++;
+        debug("bits set: %d/%d", bits_set, BN_num_bits(dh->p));
+
+        /* if g==2 and bits_set==1 then computing log_g(dh_pub) is trivial */
+        if (bits_set > 1 && (BN_cmp(dh_pub, dh->p) == -1))
+                return 1;
+        log("invalid public DH value (%d/%d)", bits_set, BN_num_bits(dh->p));
+        return 0;
+}
+
 DH *
-new_dh_group1()
+dh_new_group1()
 {
         static char *group1 =
             "FFFFFFFF" "FFFFFFFF" "C90FDAA2" "2168C234" "C4C6628B" "80DC1CD1"
@@ -96,22 +119,23 @@ new_dh_group1()
             "EE386BFB" "5A899FA5" "AE9F2411" "7C4B1FE6" "49286651" "ECE65381"
             "FFFFFFFF" "FFFFFFFF";
         DH *dh;
-        int ret;
+        int ret, tries = 0;
         dh = DH_new();
         if(dh == NULL)
                 fatal("DH_new");
-        ret = BN_hex2bn(&dh->p,group1);
+        ret = BN_hex2bn(&dh->p, group1);
         if(ret<0)
                 fatal("BN_hex2bn");
         dh->g = BN_new();
         if(dh->g == NULL)
                 fatal("DH_new g");
-        BN_set_word(dh->g,2);
-
-        seed_rng();
-        if (DH_generate_key(dh) == 0)
-                fatal("DH_generate_key");
-
+        BN_set_word(dh->g, 2);
+        do {
+                if (DH_generate_key(dh) == 0)
+                        fatal("DH_generate_key");
+                if (tries++ > 10)
+                        fatal("dh_new_group1: too many bad keys: giving up");
+        } while (!dh_pub_is_valid(dh, dh->pub_key));
         return dh;
 }
 
@@ -356,7 +380,7 @@ kex_choose_conf(char *cprop[PROPOSAL_MAX], char *sprop[PROPOSAL_MAX], int server
                 choose_enc (&k->enc [mode], cprop[nenc],  sprop[nenc]);
                 choose_mac (&k->mac [mode], cprop[nmac],  sprop[nmac]);
                 choose_comp(&k->comp[mode], cprop[ncomp], sprop[ncomp]);
-                log("kex: %s %s %s %s",
+                debug("kex: %s %s %s %s",
                     ctos ? "client->server" : "server->client",
                     k->enc[mode].name,
                     k->mac[mode].name,
diff --git a/kex.h b/kex.h
index 81c41342a..29e1e887f 100644
--- a/kex.h
+++ b/kex.h
@@ -102,7 +102,8 @@ struct Kex {
 };
 
 Buffer  *kex_init(char *myproposal[PROPOSAL_MAX]);
-DH      *new_dh_group1();
+int     dh_pub_is_valid(DH *dh, BIGNUM *dh_pub);
+DH      *dh_new_group1();
 Kex     *kex_choose_conf(char *cprop[PROPOSAL_MAX], char *sprop[PROPOSAL_MAX], int server);
 int     kex_derive_keys(Kex *k, unsigned char *hash, BIGNUM *shared_secret);
 void    bignum_print(BIGNUM *b);
diff --git a/readconf.c b/readconf.c
index bb420ac05..1ba70c36a 100644
--- a/readconf.c
+++ b/readconf.c
@@ -14,13 +14,14 @@
  */
 
 #include "includes.h"
-RCSID("$Id: readconf.c,v 1.9 2000/04/01 01:09:25 damien Exp $");
+RCSID("$Id: readconf.c,v 1.10 2000/04/12 10:17:40 damien Exp $");
 
 #include "ssh.h"
 #include "cipher.h"
 #include "readconf.h"
 #include "match.h"
 #include "xmalloc.h"
+#include "compat.h"
 
 /* Format of the configuration file:
 
@@ -103,7 +104,7 @@ typedef enum {
         oGlobalKnownHostsFile, oUserKnownHostsFile, oConnectionAttempts,
         oBatchMode, oCheckHostIP, oStrictHostKeyChecking, oCompression,
         oCompressionLevel, oKeepAlives, oNumberOfPasswordPrompts, oTISAuthentication,
-        oUsePrivilegedPort, oLogLevel
+        oUsePrivilegedPort, oLogLevel, oCiphers, oProtocol
 } OpCodes;
 
 /* Textual representations of the tokens. */
@@ -134,6 +135,8 @@ static struct {
         { "proxycommand", oProxyCommand },
         { "port", oPort },
         { "cipher", oCipher },
+        { "ciphers", oCiphers },
+        { "protocol", oProtocol },
         { "remoteforward", oRemoteForward },
         { "localforward", oLocalForward },
         { "user", oUser },
@@ -444,6 +447,26 @@ parse_int:
                         *intptr = value;
                 break;
 
+        case oCiphers:
+                cp = strtok(NULL, WHITESPACE);
+                if (!ciphers_valid(cp))
+                        fatal("%.200s line %d: Bad cipher spec '%s'.",
+                              filename, linenum, cp ? cp : "<NONE>");
+                if (*activep && options->ciphers == NULL)
+                        options->ciphers = xstrdup(cp);
+                break;
+
+        case oProtocol:
+                intptr = &options->protocol;
+                cp = strtok(NULL, WHITESPACE);
+                value = proto_spec(cp);
+                if (value == SSH_PROTO_UNKNOWN)
+                        fatal("%.200s line %d: Bad protocol spec '%s'.",
+                              filename, linenum, cp ? cp : "<NONE>");
+                if (*activep && *intptr == SSH_PROTO_UNKNOWN)
+                        *intptr = value;
+                break;
+
         case oLogLevel:
                 intptr = (int *) &options->log_level;
                 cp = strtok(NULL, WHITESPACE);
@@ -616,6 +639,8 @@ initialize_options(Options * options)
         options->connection_attempts = -1;
         options->number_of_password_prompts = -1;
         options->cipher = -1;
+        options->ciphers = NULL;
+        options->protocol = SSH_PROTO_UNKNOWN;
         options->num_identity_files = 0;
         options->hostname = NULL;
         options->proxy_command = NULL;
@@ -689,6 +714,8 @@ fill_default_options(Options * options)
         /* Selected in ssh_login(). */
         if (options->cipher == -1)
                 options->cipher = SSH_CIPHER_NOT_SET;
+        if (options->protocol == SSH_PROTO_UNKNOWN)
+                options->protocol = SSH_PROTO_1;
         if (options->num_identity_files == 0) {
                 options->identity_files[0] =
                         xmalloc(2 + strlen(SSH_CLIENT_IDENTITY) + 1);
diff --git a/readconf.h b/readconf.h
index 09f051401..86f342d37 100644
--- a/readconf.h
+++ b/readconf.h
@@ -13,7 +13,7 @@
  * 
  */
 
-/* RCSID("$Id: readconf.h,v 1.6 1999/12/06 00:47:29 damien Exp $"); */
+/* RCSID("$Id: readconf.h,v 1.7 2000/04/12 10:17:40 damien Exp $"); */
 
 #ifndef READCONF_H
 #define READCONF_H
@@ -64,6 +64,8 @@ typedef struct {
         int     number_of_password_prompts;     /* Max number of password
                                                  * prompts. */
         int     cipher;         /* Cipher to use. */
+        char   *ciphers;        /* Ciphers in order of preference. */
+        int     protocol;       /* Protocol in order of preference. */
         char   *hostname;       /* Real host to connect. */
         char   *proxy_command;  /* Proxy command for connecting the host. */
         char   *user;           /* User to log in as. */
diff --git a/servconf.c b/servconf.c
index 800c4d5f4..918fb8ed2 100644
--- a/servconf.c
+++ b/servconf.c
@@ -12,11 +12,12 @@
  */
 
 #include "includes.h"
-RCSID("$Id: servconf.c,v 1.10 2000/04/12 08:45:06 damien Exp $");
+RCSID("$Id: servconf.c,v 1.11 2000/04/12 10:17:40 damien Exp $");
 
 #include "ssh.h"
 #include "servconf.h"
 #include "xmalloc.h"
+#include "compat.h"
 
 /* add listen address */
 void add_listen_addr(ServerOptions *options, char *addr);
@@ -68,6 +69,8 @@ initialize_server_options(ServerOptions *options)
         options->num_deny_users = 0;
         options->num_allow_groups = 0;
         options->num_deny_groups = 0;
+        options->ciphers = NULL;
+        options->protocol = SSH_PROTO_UNKNOWN;
 }
 
 void 
@@ -139,6 +142,8 @@ fill_default_server_options(ServerOptions *options)
                 options->permit_empty_passwd = 0;
         if (options->use_login == -1)
                 options->use_login = 0;
+        if (options->protocol == SSH_PROTO_UNKNOWN)
+                options->protocol = SSH_PROTO_1;
 }
 
 #define WHITESPACE " \t\r\n"
@@ -162,7 +167,7 @@ typedef enum {
         sPrintMotd, sIgnoreRhosts, sX11Forwarding, sX11DisplayOffset,
         sStrictModes, sEmptyPasswd, sRandomSeedFile, sKeepAlives, sCheckMail,
         sUseLogin, sAllowUsers, sDenyUsers, sAllowGroups, sDenyGroups,
-        sIgnoreUserKnownHosts, sDSAKeyFile
+        sIgnoreUserKnownHosts, sDSAKeyFile, sCiphers, sProtocol
 } ServerOpCodes;
 
 /* Textual representation of the tokens. */
@@ -211,6 +216,8 @@ static struct {
         { "denyusers", sDenyUsers },
         { "allowgroups", sAllowGroups },
         { "denygroups", sDenyGroups },
+        { "ciphers", sCiphers },
+        { "protocol", sProtocol },
         { NULL, 0 }
 };
 
@@ -494,7 +501,7 @@ parse_flag:
                         value = log_facility_number(cp);
                         if (value == (SyslogFacility) - 1)
                                 fatal("%.200s line %d: unsupported log facility '%s'\n",
-                                  filename, linenum, cp ? cp : "<NONE>");
+                                    filename, linenum, cp ? cp : "<NONE>");
                         if (*intptr == -1)
                                 *intptr = (SyslogFacility) value;
                         break;
@@ -505,55 +512,67 @@ parse_flag:
                         value = log_level_number(cp);
                         if (value == (LogLevel) - 1)
                                 fatal("%.200s line %d: unsupported log level '%s'\n",
-                                  filename, linenum, cp ? cp : "<NONE>");
+                                    filename, linenum, cp ? cp : "<NONE>");
                         if (*intptr == -1)
                                 *intptr = (LogLevel) value;
                         break;
 
                 case sAllowUsers:
                         while ((cp = strtok(NULL, WHITESPACE))) {
-                                if (options->num_allow_users >= MAX_ALLOW_USERS) {
-                                        fprintf(stderr, "%s line %d: too many allow users.\n",
-                                                filename, linenum);
-                                        exit(1);
-                                }
+                                if (options->num_allow_users >= MAX_ALLOW_USERS)
+                                        fatal("%s line %d: too many allow users.\n",
+                                            filename, linenum);
                                 options->allow_users[options->num_allow_users++] = xstrdup(cp);
                         }
                         break;
 
                 case sDenyUsers:
                         while ((cp = strtok(NULL, WHITESPACE))) {
-                                if (options->num_deny_users >= MAX_DENY_USERS) {
-                                        fprintf(stderr, "%s line %d: too many deny users.\n",
-                                                filename, linenum);
-                                        exit(1);
-                                }
+                                if (options->num_deny_users >= MAX_DENY_USERS)
+                                        fatal( "%s line %d: too many deny users.\n",
+                                            filename, linenum);
                                 options->deny_users[options->num_deny_users++] = xstrdup(cp);
                         }
                         break;
 
                 case sAllowGroups:
                         while ((cp = strtok(NULL, WHITESPACE))) {
-                                if (options->num_allow_groups >= MAX_ALLOW_GROUPS) {
-                                        fprintf(stderr, "%s line %d: too many allow groups.\n",
-                                                filename, linenum);
-                                        exit(1);
-                                }
+                                if (options->num_allow_groups >= MAX_ALLOW_GROUPS)
+                                        fatal("%s line %d: too many allow groups.\n",
+                                            filename, linenum);
                                 options->allow_groups[options->num_allow_groups++] = xstrdup(cp);
                         }
                         break;
 
                 case sDenyGroups:
                         while ((cp = strtok(NULL, WHITESPACE))) {
-                                if (options->num_deny_groups >= MAX_DENY_GROUPS) {
-                                        fprintf(stderr, "%s line %d: too many deny groups.\n",
-                                                filename, linenum);
-                                        exit(1);
-                                }
+                                if (options->num_deny_groups >= MAX_DENY_GROUPS)
+                                        fatal("%s line %d: too many deny groups.\n",
+                                            filename, linenum);
                                 options->deny_groups[options->num_deny_groups++] = xstrdup(cp);
                         }
                         break;
 
+                case sCiphers:
+                        cp = strtok(NULL, WHITESPACE);
+                        if (!ciphers_valid(cp))
+                                fatal("%s line %d: Bad cipher spec '%s'.",
+                                    filename, linenum, cp ? cp : "<NONE>");
+                        if (options->ciphers == NULL)
+                                options->ciphers = xstrdup(cp);
+                        break;
+
+                case sProtocol:
+                        intptr = &options->protocol;
+                        cp = strtok(NULL, WHITESPACE);
+                        value = proto_spec(cp);
+                        if (value == SSH_PROTO_UNKNOWN)
+                                fatal("%s line %d: Bad protocol spec '%s'.",
+                                      filename, linenum, cp ? cp : "<NONE>");
+                        if (*intptr == SSH_PROTO_UNKNOWN)
+                                *intptr = value;
+                        break;
+
                 default:
                         fprintf(stderr, "%s line %d: Missing handler for opcode %s (%d)\n",
                                 filename, linenum, cp, opcode);
diff --git a/servconf.h b/servconf.h
index 5ce3f1594..2a3686245 100644
--- a/servconf.h
+++ b/servconf.h
@@ -13,7 +13,7 @@
  * 
  */
 
-/* RCSID("$Id: servconf.h,v 1.7 2000/04/12 08:45:07 damien Exp $"); */
+/* RCSID("$Id: servconf.h,v 1.8 2000/04/12 10:17:40 damien Exp $"); */
 
 #ifndef SERVCONF_H
 #define SERVCONF_H
@@ -48,6 +48,8 @@ typedef struct {
                                          * searching at */
         int     strict_modes;   /* If true, require string home dir modes. */
         int     keepalives;     /* If true, set SO_KEEPALIVE. */
+        char   *ciphers;        /* Ciphers in order of preference. */
+        int     protocol;       /* Protocol in order of preference. */
         SyslogFacility log_facility;    /* Facility for system logging. */
         LogLevel log_level;     /* Level for system logging. */
         int     rhosts_authentication;  /* If true, permit rhosts
diff --git a/ssh.c b/ssh.c
index cce0e6b7f..f23694247 100644
--- a/ssh.c
+++ b/ssh.c
@@ -11,7 +11,7 @@
  */
 
 #include "includes.h"
-RCSID("$Id: ssh.c,v 1.24 2000/04/06 02:32:40 damien Exp $");
+RCSID("$Id: ssh.c,v 1.25 2000/04/12 10:17:40 damien Exp $");
 
 #include "xmalloc.h"
 #include "ssh.h"
@@ -42,6 +42,7 @@ int IPv4or6 = AF_UNSPEC;
 /* Flag indicating whether debug mode is on.  This can be set on the command line. */
 int debug_flag = 0;
 
+/* Flag indicating whether a tty should be allocated */
 int tty_flag = 0;
 
 /* don't exec a shell */
@@ -336,8 +337,10 @@ main(int ac, char **av)
 
                 case 'v':
                 case 'V':
-                        fprintf(stderr, "SSH Version %s, protocol version %d.%d.\n",
-                            SSH_VERSION, PROTOCOL_MAJOR, PROTOCOL_MINOR);
+                        fprintf(stderr, "SSH Version %s, protocol versions %d.%d/%d.%d.\n",
+                            SSH_VERSION,
+                            PROTOCOL_MAJOR_1, PROTOCOL_MINOR_1,
+                            PROTOCOL_MAJOR_2, PROTOCOL_MINOR_2);
                         fprintf(stderr, "Compiled with SSL (0x%8.8lx).\n", SSLeay());
                         if (opt == 'V')
                                 exit(0);
diff --git a/ssh.h b/ssh.h
index 7c5bf9c52..ea2dc032c 100644
--- a/ssh.h
+++ b/ssh.h
@@ -13,7 +13,7 @@
  * 
  */
 
-/* RCSID("$Id: ssh.h,v 1.30 2000/04/12 08:45:07 damien Exp $"); */
+/* RCSID("$Id: ssh.h,v 1.31 2000/04/12 10:17:41 damien Exp $"); */
 
 #ifndef SSH_H
 #define SSH_H
@@ -54,14 +54,16 @@
 /*
  * Major protocol version.  Different version indicates major incompatiblity
  * that prevents communication.
- */
-#define PROTOCOL_MAJOR          1
-
-/*
+ *
  * Minor protocol version.  Different version indicates minor incompatibility
  * that does not prevent interoperation.
  */
-#define PROTOCOL_MINOR          5
+#define PROTOCOL_MAJOR_1        1
+#define PROTOCOL_MINOR_1        5
+
+/* We support both SSH1 and SSH2 */
+#define PROTOCOL_MAJOR_2        2
+#define PROTOCOL_MINOR_2        0
 
 /*
  * Name for the service.  The port named by this service overrides the
diff --git a/sshconnect.c b/sshconnect.c
index 2f9496090..167b8e63a 100644
--- a/sshconnect.c
+++ b/sshconnect.c
@@ -10,7 +10,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshconnect.c,v 1.61 2000/04/04 21:37:27 markus Exp $");
+RCSID("$OpenBSD: sshconnect.c,v 1.65 2000/04/12 07:56:16 markus Exp $");
 
 #ifdef HAVE_OPENSSL
 #include <openssl/bn.h>
@@ -993,7 +993,7 @@ 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();
 
@@ -1027,39 +1027,51 @@ ssh_exchange_identification()
         debug("Remote protocol version %d.%d, remote software version %.100s",
               remote_major, remote_minor, remote_version);
 
-/*** XXX option for disabling 2.0 or 1.5 */
         compat_datafellows(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.");
-
-        /* 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;
+        mismatch = 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 ((remote_major == 2 && remote_minor == 0) ||
-            (remote_major == 1 && remote_minor == 99)) {
-                enable_compat20();
-        }
-#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);
+
         /* Send our own protocol version identification. */
         snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
-            compat20 ? 2 : PROTOCOL_MAJOR,
-            compat20 ? 0 : PROTOCOL_MINOR,
+            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));
@@ -1350,11 +1362,15 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
 /* KEXINIT */
 
         debug("Sending KEX init.");
-        if (options.cipher == SSH_CIPHER_ARCFOUR ||
+        if (options.ciphers != NULL) {
+                myproposal[PROPOSAL_ENC_ALGS_CTOS] = 
+                myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
+        } else if (
+            options.cipher == SSH_CIPHER_ARCFOUR ||
             options.cipher == SSH_CIPHER_3DES_CBC ||
             options.cipher == SSH_CIPHER_CAST128_CBC ||
             options.cipher == SSH_CIPHER_BLOWFISH_CBC) {
-                myproposal[PROPOSAL_ENC_ALGS_CTOS] = cipher_name(options.cipher);
+                myproposal[PROPOSAL_ENC_ALGS_CTOS] =
                 myproposal[PROPOSAL_ENC_ALGS_STOC] = cipher_name(options.cipher);
         }
         if (options.compression) {
@@ -1404,7 +1420,7 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         debug("Sending SSH2_MSG_KEXDH_INIT.");
 
         /* generate and send 'e', client DH public key */
-        dh = new_dh_group1();
+        dh = dh_new_group1();
         packet_start(SSH2_MSG_KEXDH_INIT);
         packet_put_bignum2(dh->pub_key);
         packet_send();
@@ -1451,6 +1467,9 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         /* signed H */
         signature = packet_get_string(&slen);
 
+        if (!dh_pub_is_valid(dh, dh_server_pub))
+                packet_disconnect("bad server public DH value");
+
         klen = DH_size(dh);
         kbuf = xmalloc(klen);
         kout = DH_compute_key(kbuf, dh_server_pub, dh);
@@ -1507,12 +1526,13 @@ ssh_kex2(char *host, struct sockaddr *hostaddr)
         packet_write_wait();
         debug("done: send SSH2_MSG_NEWKEYS.");
 
+#ifdef DEBUG_KEXDH
         /* send 1st encrypted/maced/compressed message */
         packet_start(SSH2_MSG_IGNORE);
         packet_put_cstring("markus");
         packet_send();
         packet_write_wait();
-
+#endif
         debug("done: KEX2.");
 }
 /*
@@ -1527,6 +1547,7 @@ ssh_userauth2(int host_key_valid, RSA *own_host_key,
         unsigned int dlen;
         int partial;
         struct passwd *pw;
+        char prompt[80];
         char *server_user, *local_user;
         char *auths;
         char *password;
@@ -1578,7 +1599,9 @@ ssh_userauth2(int host_key_valid, RSA *own_host_key,
                         fatal("passwd auth not supported: %s", auths);
                 xfree(auths);
                 /* try passwd */
-                password = read_passphrase("password: ", 0);
+                snprintf(prompt, sizeof(prompt), "%.30s@%.40s's password: ",
+                    server_user, host);
+                password = read_passphrase(prompt, 0);
                 packet_start(SSH2_MSG_USERAUTH_REQUEST);
                 packet_put_cstring(server_user);
                 packet_put_cstring(service);
diff --git a/sshd.c b/sshd.c
index 44782e397..266146bf0 100644
--- a/sshd.c
+++ b/sshd.c
@@ -14,7 +14,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.99 2000/04/07 09:17:39 markus Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.103 2000/04/12 08:11:36 markus Exp $");
 
 #include "xmalloc.h"
 #include "rsa.h"
@@ -77,9 +77,6 @@ int IPv4or6 = AF_INET;
 int IPv4or6 = AF_UNSPEC;
 #endif
 
-/* Flag indicating whether SSH2 is enabled */
-int allow_ssh2 = 0;
-
 /*
  * Debug mode flag.  This can be set on the command line.  If debug
  * mode is enabled, extra debugging output will be sent to the system
@@ -284,16 +281,25 @@ chop(char *s)
 void
 sshd_exchange_identification(int sock_in, int sock_out)
 {
-        int i;
+        int i, mismatch;
         int remote_major, remote_minor;
+        int major, minor;
         char *s;
         char buf[256];                  /* Must not be larger than remote_version. */
         char remote_version[256];       /* Must be at least as big as buf. */
 
-        snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
-                 allow_ssh2 ? 1  : PROTOCOL_MAJOR,
-                 allow_ssh2 ? 99 : PROTOCOL_MINOR,
-                 SSH_VERSION);
+        if ((options.protocol & SSH_PROTO_1) &&
+            (options.protocol & SSH_PROTO_2)) {
+                major = PROTOCOL_MAJOR_1;
+                minor = 99;
+        } else if (options.protocol & SSH_PROTO_2) {
+                major = PROTOCOL_MAJOR_2;
+                minor = PROTOCOL_MINOR_2;
+        } else {
+                major = PROTOCOL_MAJOR_1;
+                minor = PROTOCOL_MINOR_1;
+        }
+        snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n", major, minor, SSH_VERSION);
         server_version_string = xstrdup(buf);
 
         if (client_version_string == NULL) {
@@ -314,7 +320,6 @@ sshd_exchange_identification(int sock_in, int sock_out)
                                 buf[i] = '\n';
                                 buf[i + 1] = 0;
                                 continue;
-                                //break;
                         }
                         if (buf[i] == '\n') {
                                 /* buf[i] == '\n' */
@@ -345,8 +350,13 @@ sshd_exchange_identification(int sock_in, int sock_out)
 
         compat_datafellows(remote_version);
 
+        mismatch = 0;
         switch(remote_major) {
         case 1:
+                if (!(options.protocol & SSH_PROTO_1)) {
+                        mismatch = 1;
+                        break;
+                }
                 if (remote_minor < 3) {
                         packet_disconnect("Your ssh version is too old and"
                             "is no longer supported.  Please install a newer version.");
@@ -354,27 +364,37 @@ sshd_exchange_identification(int sock_in, int sock_out)
                         /* note that this disables agent-forwarding */
                         enable_compat13();
                 }
-                if (remote_minor != 99)
-                       break;
-                /* FALLTHROUGH */
+                if (remote_minor == 99) {
+                        if (options.protocol & SSH_PROTO_2)
+                                enable_compat20();
+                        else
+                                mismatch = 1;
+                }
+                break;
         case 2:
-                if (allow_ssh2) {
+                if (options.protocol & SSH_PROTO_2) {
                         enable_compat20();
                         break;
                 }
                 /* FALLTHROUGH */
         default: 
+                mismatch = 1;
+                break;
+        }
+        chop(server_version_string);
+        chop(client_version_string);
+        debug("Local version string %.200s", server_version_string);
+
+        if (mismatch) {
                 s = "Protocol major versions differ.\n";
                 (void) atomicio(write, sock_out, s, strlen(s));
                 close(sock_in);
                 close(sock_out);
-                log("Protocol major versions differ for %s: %d vs. %d",
-                    get_remote_ipaddr(), PROTOCOL_MAJOR, remote_major);
+                log("Protocol major versions differ for %s: %.200s vs. %.200s",
+                    get_remote_ipaddr(),
+                    server_version_string, client_version_string);
                 fatal_cleanup();
-                break;
         }
-        chop(server_version_string);
-        chop(client_version_string);
 }
 
 /*
@@ -410,11 +430,8 @@ main(int ac, char **av)
         initialize_server_options(&options);
 
         /* Parse command-line arguments. */
-        while ((opt = getopt(ac, av, "f:p:b:k:h:g:V:diqQ246")) != EOF) {
+        while ((opt = getopt(ac, av, "f:p:b:k:h:g:V:diqQ46")) != EOF) {
                 switch (opt) {
-                case '2':
-                        allow_ssh2 = 1;
-                        break;
                 case '4':
                         IPv4or6 = AF_INET;
                         break;
@@ -593,6 +610,7 @@ main(int ac, char **av)
                 public_key = RSA_new();
                 sensitive_data.private_key = RSA_new();
 
+                /* XXX check options.protocol */
                 log("Generating %d bit RSA key.", options.server_key_bits);
                 rsa_generate_key(sensitive_data.private_key, public_key,
                                  options.server_key_bits);
@@ -1126,6 +1144,11 @@ do_ssh2_kex()
 
 /* KEXINIT */
 
+        if (options.ciphers != NULL) {
+                myproposal[PROPOSAL_ENC_ALGS_CTOS] = 
+                myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
+        }
+
         debug("Sending KEX init.");
 
         for (i = 0; i < PROPOSAL_MAX; i++)
@@ -1185,7 +1208,7 @@ do_ssh2_kex()
 #endif
 
         /* generate DH key */
-        dh = new_dh_group1();                   /* XXX depends on 'kex' */
+        dh = dh_new_group1();                   /* XXX depends on 'kex' */
 
 #ifdef DEBUG_KEXDH
         fprintf(stderr, "\np= ");
@@ -1196,6 +1219,8 @@ do_ssh2_kex()
         bignum_print(dh->pub_key);
         fprintf(stderr, "\n");
 #endif
+        if (!dh_pub_is_valid(dh, dh_client_pub))
+                packet_disconnect("bad client public DH value");
 
         klen = DH_size(dh);
         kbuf = xmalloc(klen);
@@ -1267,11 +1292,12 @@ do_ssh2_kex()
         packet_read_expect(&payload_len, SSH2_MSG_NEWKEYS);
         debug("GOT SSH2_MSG_NEWKEYS.");
 
+#ifdef DEBUG_KEXDH
         /* send 1st encrypted/maced/compressed message */
         packet_start(SSH2_MSG_IGNORE);
         packet_put_cstring("markus");
         packet_send();
         packet_write_wait();
-
+#endif
         debug("done: KEX2.");
 }