Merged SSH1 robustness changes from 0.55 release branch on to trunk.
[u/mdw/putty] / ssh.c
diff --git a/ssh.c b/ssh.c
index 81ca0c8..2019d48 100644 (file)
--- a/ssh.c
+++ b/ssh.c
@@ -573,6 +573,7 @@ struct ssh_tag {
 
     void *frontend;
 
+    int ospeed, ispeed;                       /* temporaries */
     int term_width, term_height;
 
     tree234 *channels;                /* indexed by local id */
@@ -662,7 +663,7 @@ struct ssh_tag {
 #define logevent(s) logevent(ssh->frontend, s)
 
 /* logevent, only printf-formatted. */
-static void logeventf(Ssh ssh, char *fmt, ...)
+static void logeventf(Ssh ssh, const char *fmt, ...)
 {
     va_list ap;
     char *buf;
@@ -856,7 +857,7 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
     if (ssh->cipher)
        ssh->cipher->decrypt(ssh->v1_cipher_ctx, ssh->pktin.data, st->biglen);
 
-    st->realcrc = crc32(ssh->pktin.data, st->biglen - 4);
+    st->realcrc = crc32_compute(ssh->pktin.data, st->biglen - 4);
     st->gotcrc = GET_32BIT(ssh->pktin.data + st->biglen - 4);
     if (st->gotcrc != st->realcrc) {
        bombout(("Incorrect CRC received on packet"));
@@ -864,13 +865,17 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
     }
 
     ssh->pktin.body = ssh->pktin.data + st->pad + 1;
+    ssh->pktin.savedpos = 0;
 
     if (ssh->v1_compressing) {
        unsigned char *decompblk;
        int decomplen;
-       zlib_decompress_block(ssh->sc_comp_ctx,
-                             ssh->pktin.body - 1, ssh->pktin.length + 1,
-                             &decompblk, &decomplen);
+       if (!zlib_decompress_block(ssh->sc_comp_ctx,
+                                  ssh->pktin.body - 1, ssh->pktin.length + 1,
+                                  &decompblk, &decomplen)) {
+           bombout(("Zlib decompression encountered invalid data"));
+           crStop(0);
+       }
 
        if (ssh->pktin.maxlen < st->pad + decomplen) {
            ssh->pktin.maxlen = st->pad + decomplen;
@@ -1065,6 +1070,7 @@ static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
     }
 
     ssh->pktin.savedpos = 6;
+    ssh->pktin.body = ssh->pktin.data;
     ssh->pktin.type = ssh->pktin.data[5];
 
     if (ssh->logctx)
@@ -1244,7 +1250,7 @@ static int s_wrpkt_prepare(Ssh ssh)
 
     for (i = 0; i < pad; i++)
        ssh->pktout.data[i + 4] = random_byte();
-    crc = crc32(ssh->pktout.data + 4, biglen - 4);
+    crc = crc32_compute(ssh->pktout.data + 4, biglen - 4);
     PUT_32BIT(ssh->pktout.data + biglen, crc);
     PUT_32BIT(ssh->pktout.data, len);
 
@@ -1635,14 +1641,14 @@ static void sha_mpint(SHA_State * s, Bignum b)
 }
 
 /*
- * SSH2 packet decode functions.
+ * Packet decode functions for both SSH1 and SSH2.
  */
-static unsigned long ssh2_pkt_getuint32(Ssh ssh)
+static unsigned long ssh_pkt_getuint32(Ssh ssh)
 {
     unsigned long value;
     if (ssh->pktin.length - ssh->pktin.savedpos < 4)
        return 0;                      /* arrgh, no way to decline (FIXME?) */
-    value = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
+    value = GET_32BIT(ssh->pktin.body + ssh->pktin.savedpos);
     ssh->pktin.savedpos += 4;
     return value;
 }
@@ -1651,34 +1657,72 @@ static int ssh2_pkt_getbool(Ssh ssh)
     unsigned long value;
     if (ssh->pktin.length - ssh->pktin.savedpos < 1)
        return 0;                      /* arrgh, no way to decline (FIXME?) */
-    value = ssh->pktin.data[ssh->pktin.savedpos] != 0;
+    value = ssh->pktin.body[ssh->pktin.savedpos] != 0;
     ssh->pktin.savedpos++;
     return value;
 }
-static void ssh2_pkt_getstring(Ssh ssh, char **p, int *length)
+static void ssh_pkt_getstring(Ssh ssh, char **p, int *length)
 {
     int len;
     *p = NULL;
     *length = 0;
     if (ssh->pktin.length - ssh->pktin.savedpos < 4)
        return;
-    len = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
+    len = GET_32BIT(ssh->pktin.body + ssh->pktin.savedpos);
     if (len < 0)
        return;
     *length = len;
     ssh->pktin.savedpos += 4;
     if (ssh->pktin.length - ssh->pktin.savedpos < *length)
        return;
-    *p = (char *)(ssh->pktin.data + ssh->pktin.savedpos);
+    *p = (char *)(ssh->pktin.body + ssh->pktin.savedpos);
     ssh->pktin.savedpos += *length;
 }
+static void *ssh_pkt_getdata(Ssh ssh, int length)
+{
+    if (ssh->pktin.length - ssh->pktin.savedpos < length)
+       return NULL;
+    ssh->pktin.savedpos += length;
+    return ssh->pktin.body + (ssh->pktin.savedpos - length);
+}
+static int ssh1_pkt_getrsakey(Ssh ssh, struct RSAKey *key,
+                             unsigned char **keystr)
+{
+    int j;
+
+    j = makekey(ssh->pktin.body + ssh->pktin.savedpos,
+               ssh->pktin.length - ssh->pktin.savedpos,
+               key, keystr, 0);
+
+    if (j < 0)
+       return FALSE;
+    
+    ssh->pktin.savedpos += j;
+    assert(ssh->pktin.savedpos < ssh->pktin.length);
+
+    return TRUE;
+}
+static Bignum ssh1_pkt_getmp(Ssh ssh)
+{
+    int j;
+    Bignum b;
+
+    j = ssh1_read_bignum(ssh->pktin.body + ssh->pktin.savedpos,
+                        ssh->pktin.length - ssh->pktin.savedpos, &b);
+
+    if (j < 0)
+       return NULL;
+
+    ssh->pktin.savedpos += j;
+    return b;
+}
 static Bignum ssh2_pkt_getmp(Ssh ssh)
 {
     char *p;
     int length;
     Bignum b;
 
-    ssh2_pkt_getstring(ssh, &p, &length);
+    ssh_pkt_getstring(ssh, &p, &length);
     if (!p)
        return NULL;
     if (p[0] & 0x80) {
@@ -1777,7 +1821,8 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
        (ssh->cfg.sshbug_ignore1 == AUTO &&
         (!strcmp(imp, "1.2.18") || !strcmp(imp, "1.2.19") ||
          !strcmp(imp, "1.2.20") || !strcmp(imp, "1.2.21") ||
-         !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25")))) {
+         !strcmp(imp, "1.2.22") || !strcmp(imp, "Cisco-1.25") ||
+         !strcmp(imp, "OSU_1.4alpha3")))) {
        /*
         * These versions don't support SSH1_MSG_IGNORE, so we have
         * to use a different defence against password length
@@ -1789,7 +1834,7 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (ssh->cfg.sshbug_plainpw1 == FORCE_ON ||
        (ssh->cfg.sshbug_plainpw1 == AUTO &&
-        (!strcmp(imp, "Cisco-1.25")))) {
+        (!strcmp(imp, "Cisco-1.25") || !strcmp(imp, "OSU_1.4alpha3")))) {
        /*
         * These versions need a plain password sent; they can't
         * handle having a null and a random length of data after
@@ -1813,6 +1858,7 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (ssh->cfg.sshbug_hmac2 == FORCE_ON ||
        (ssh->cfg.sshbug_hmac2 == AUTO &&
+        !wc_match("* VShell", imp) &&
         (wc_match("2.1.0*", imp) || wc_match("2.0.*", imp) ||
          wc_match("2.2.0*", imp) || wc_match("2.3.0*", imp) ||
          wc_match("2.1 *", imp)))) {
@@ -1825,6 +1871,7 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (ssh->cfg.sshbug_derivekey2 == FORCE_ON ||
        (ssh->cfg.sshbug_derivekey2 == AUTO &&
+        !wc_match("* VShell", imp) &&
         (wc_match("2.0.0*", imp) || wc_match("2.0.10*", imp) ))) {
        /*
         * These versions have the key-derivation bug (failing to
@@ -2077,7 +2124,7 @@ static void ssh_do_close(Ssh ssh)
     }
 }
 
-static int ssh_closing(Plug plug, char *error_msg, int error_code,
+static int ssh_closing(Plug plug, const char *error_msg, int error_code,
                       int calling_back)
 {
     Ssh ssh = (Ssh) plug;
@@ -2085,7 +2132,7 @@ static int ssh_closing(Plug plug, char *error_msg, int error_code,
     if (error_msg) {
        /* A socket error has occurred. */
        logevent(error_msg);
-       connection_fatal(ssh->frontend, error_msg);
+       connection_fatal(ssh->frontend, "%s", error_msg);
     } else {
        /* Otherwise, the remote side closed the connection normally. */
     }
@@ -2120,8 +2167,8 @@ static void ssh_sent(Plug plug, int bufsize)
  * Also places the canonical host name into `realhost'. It must be
  * freed by the caller.
  */
-static char *connect_to_host(Ssh ssh, char *host, int port,
-                            char **realhost, int nodelay)
+static const char *connect_to_host(Ssh ssh, char *host, int port,
+                                  char **realhost, int nodelay, int keepalive)
 {
     static const struct plug_function_table fn_table = {
        ssh_closing,
@@ -2131,7 +2178,7 @@ static char *connect_to_host(Ssh ssh, char *host, int port,
     };
 
     SockAddr addr;
-    char *err;
+    const char *err;
 
     ssh->savedhost = snewn(1 + strlen(host), char);
     if (!ssh->savedhost)
@@ -2147,8 +2194,10 @@ static char *connect_to_host(Ssh ssh, char *host, int port,
      */
     logeventf(ssh, "Looking up host \"%s\"", host);
     addr = name_lookup(host, port, realhost, &ssh->cfg);
-    if ((err = sk_addr_error(addr)) != NULL)
+    if ((err = sk_addr_error(addr)) != NULL) {
+       sk_addr_free(addr);
        return err;
+    }
 
     /*
      * Open socket.
@@ -2160,7 +2209,7 @@ static char *connect_to_host(Ssh ssh, char *host, int port,
     }
     ssh->fn = &fn_table;
     ssh->s = new_connection(addr, *realhost, port,
-                           0, 1, nodelay, (Plug) ssh, &ssh->cfg);
+                           0, 1, nodelay, keepalive, (Plug) ssh, &ssh->cfg);
     if ((err = sk_socket_error(ssh->s)) != NULL) {
        ssh->s = NULL;
        return err;
@@ -2291,7 +2340,7 @@ static int process_userpass_input(Ssh ssh, unsigned char *in, int inlen)
     return 0;
 }
 
-void ssh_agent_callback(void *sshv, void *reply, int replylen)
+static void ssh_agent_callback(void *sshv, void *reply, int replylen)
 {
     Ssh ssh = (Ssh) sshv;
 
@@ -2304,7 +2353,7 @@ void ssh_agent_callback(void *sshv, void *reply, int replylen)
        do_ssh2_authconn(ssh, NULL, -1, 0);
 }
 
-void ssh_agentf_callback(void *cv, void *reply, int replylen)
+static void ssh_agentf_callback(void *cv, void *reply, int replylen)
 {
     struct ssh_channel *c = (struct ssh_channel *)cv;
     Ssh ssh = c->ssh;
@@ -2334,8 +2383,8 @@ void ssh_agentf_callback(void *cv, void *reply, int replylen)
  */
 static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 {
-    int i, j;
-    unsigned char cookie[8];
+    int i, j, ret;
+    unsigned char cookie[8], *ptr;
     struct RSAKey servkey, hostkey;
     struct MD5Context md5c;
     struct do_ssh1_login_state {
@@ -2377,10 +2426,18 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
     logevent("Received public keys");
 
-    memcpy(cookie, ssh->pktin.body, 8);
+    ptr = ssh_pkt_getdata(ssh, 8);
+    if (!ptr) {
+       bombout(("SSH1 public key packet stopped before random cookie"));
+       crStop(0);
+    }
+    memcpy(cookie, ptr, 8);
 
-    i = makekey(ssh->pktin.body + 8, &servkey, &s->keystr1, 0);
-    j = makekey(ssh->pktin.body + 8 + i, &hostkey, &s->keystr2, 0);
+    if (!ssh1_pkt_getrsakey(ssh, &servkey, &s->keystr1) ||
+       !ssh1_pkt_getrsakey(ssh, &hostkey, &s->keystr2)) {      
+       bombout(("SSH1 public key packet stopped before public keys"));
+       crStop(0);
+    }
 
     /*
      * Log the host key fingerprint.
@@ -2395,9 +2452,9 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        logevent(logmsg);
     }
 
-    ssh->v1_remote_protoflags = GET_32BIT(ssh->pktin.body + 8 + i + j);
-    s->supported_ciphers_mask = GET_32BIT(ssh->pktin.body + 12 + i + j);
-    s->supported_auths_mask = GET_32BIT(ssh->pktin.body + 16 + i + j);
+    ssh->v1_remote_protoflags = ssh_pkt_getuint32(ssh);
+    s->supported_ciphers_mask = ssh_pkt_getuint32(ssh);
+    s->supported_auths_mask = ssh_pkt_getuint32(ssh);
 
     ssh->v1_local_protoflags =
        ssh->v1_remote_protoflags & SSH1_PROTOFLAGS_SUPPORTED;
@@ -2406,12 +2463,21 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     MD5Init(&md5c);
     MD5Update(&md5c, s->keystr2, hostkey.bytes);
     MD5Update(&md5c, s->keystr1, servkey.bytes);
-    MD5Update(&md5c, ssh->pktin.body, 8);
+    MD5Update(&md5c, cookie, 8);
     MD5Final(s->session_id, &md5c);
 
     for (i = 0; i < 32; i++)
        ssh->session_key[i] = random_byte();
 
+    /*
+     * Verify that the `bits' and `bytes' parameters match.
+     */
+    if (hostkey.bits > hostkey.bytes * 8 ||
+       servkey.bits > servkey.bytes * 8) {
+       bombout(("SSH1 public keys were badly formatted"));
+       crStop(0);
+    }
+
     s->len = (hostkey.bytes > servkey.bytes ? hostkey.bytes : servkey.bytes);
 
     s->rsabuf = snewn(s->len, unsigned char);
@@ -2445,11 +2511,17 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     }
 
     if (hostkey.bytes > servkey.bytes) {
-       rsaencrypt(s->rsabuf, 32, &servkey);
-       rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
+       ret = rsaencrypt(s->rsabuf, 32, &servkey);
+       if (ret)
+           ret = rsaencrypt(s->rsabuf, servkey.bytes, &hostkey);
     } else {
-       rsaencrypt(s->rsabuf, 32, &hostkey);
-       rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
+       ret = rsaencrypt(s->rsabuf, 32, &hostkey);
+       if (ret)
+           ret = rsaencrypt(s->rsabuf, hostkey.bytes, &servkey);
+    }
+    if (!ret) {
+       bombout(("SSH1 public key encryptions failed due to bad formatting"));
+       crStop(0);      
     }
 
     logevent("Encrypted session key");
@@ -2527,6 +2599,22 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     ssh->crcda_ctx = crcda_make_context();
     logevent("Installing CRC compensation attack detector");
 
+    if (servkey.modulus) {
+       sfree(servkey.modulus);
+       servkey.modulus = NULL;
+    }
+    if (servkey.exponent) {
+       sfree(servkey.exponent);
+       servkey.exponent = NULL;
+    }
+    if (hostkey.modulus) {
+       sfree(hostkey.modulus);
+       hostkey.modulus = NULL;
+    }
+    if (hostkey.exponent) {
+       sfree(hostkey.exponent);
+       hostkey.exponent = NULL;
+    }
     crWaitUntil(ispkt);
 
     if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
@@ -2594,7 +2682,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     /* Load the public half of ssh->cfg.keyfile so we notice if it's in Pageant */
     if (!filename_is_null(ssh->cfg.keyfile)) {
        if (!rsakey_pubblob(&ssh->cfg.keyfile,
-                           &s->publickey_blob, &s->publickey_bloblen))
+                           &s->publickey_blob, &s->publickey_bloblen, NULL))
            s->publickey_blob = NULL;
     } else
        s->publickey_blob = NULL;
@@ -2652,12 +2740,37 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                        s->tried_publickey = 1;
                    }
                    s->p += 4;
-                   s->p += ssh1_read_bignum(s->p, &s->key.exponent);
-                   s->p += ssh1_read_bignum(s->p, &s->key.modulus);
-                   s->commentlen = GET_32BIT(s->p);
-                   s->p += 4;
-                   s->commentp = (char *)s->p;
-                   s->p += s->commentlen;
+                   {
+                       int n, ok = FALSE;
+                       do {           /* do while (0) to make breaking easy */
+                           n = ssh1_read_bignum
+                               (s->p, s->responselen-(s->p-s->response),
+                                &s->key.exponent);
+                           if (n < 0)
+                               break;
+                           s->p += n;
+                           n = ssh1_read_bignum
+                               (s->p, s->responselen-(s->p-s->response),
+                                &s->key.modulus);
+                           if (n < 0)
+                           break;
+                           s->p += n;
+                           if (s->responselen - (s->p-s->response) < 4)
+                               break;
+                           s->commentlen = GET_32BIT(s->p);
+                           s->p += 4;
+                           if (s->responselen - (s->p-s->response) <
+                               s->commentlen)
+                               break;
+                           s->commentp = (char *)s->p;
+                           s->p += s->commentlen;
+                           ok = TRUE;
+                       } while (0);
+                       if (!ok) {
+                           logevent("Pageant key list packet was truncated");
+                           break;
+                       }
+                   }
                    send_packet(ssh, SSH1_CMSG_AUTH_RSA,
                                PKT_BIGNUM, s->key.modulus, PKT_END);
                    crWaitUntil(ispkt);
@@ -2666,7 +2779,11 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                        continue;
                    }
                    logevent("Received RSA challenge");
-                   ssh1_read_bignum(ssh->pktin.body, &s->challenge);
+                   if ((s->challenge = ssh1_pkt_getmp(ssh)) == NULL) {
+                       bombout(("Server's RSA challenge was badly formatted"));
+                       crStop(0);
+                   }
+
                    {
                        char *agentreq, *q, *ret;
                        void *vret;
@@ -2743,6 +2860,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    if (s->authed)
                        break;
                }
+               sfree(s->response);
            }
            if (s->authed)
                break;
@@ -2764,11 +2882,18 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                s->tis_auth_refused = 1;
                continue;
            } else {
-               int challengelen = GET_32BIT(ssh->pktin.body);
+               char *challenge;
+               int challengelen;
+
+               ssh_pkt_getstring(ssh, &challenge, &challengelen);
+               if (!challenge) {
+                   bombout(("TIS challenge packet was badly formed"));
+                   crStop(0);
+               }
                logevent("Received TIS challenge");
                if (challengelen > sizeof(s->prompt) - 1)
                    challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
-               memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
+               memcpy(s->prompt, challenge, challengelen);
                /* Prompt heuristic comes from OpenSSH */
                strncpy(s->prompt + challengelen,
                        memchr(s->prompt, '\n', challengelen) ?
@@ -2790,11 +2915,18 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                s->ccard_auth_refused = 1;
                continue;
            } else {
-               int challengelen = GET_32BIT(ssh->pktin.body);
+               char *challenge;
+               int challengelen;
+
+               ssh_pkt_getstring(ssh, &challenge, &challengelen);
+               if (!challenge) {
+                   bombout(("CryptoCard challenge packet was badly formed"));
+                   crStop(0);
+               }
                logevent("Received CryptoCard challenge");
                if (challengelen > sizeof(s->prompt) - 1)
                    challengelen = sizeof(s->prompt) - 1;/* prevent overrun */
-               memcpy(s->prompt, ssh->pktin.body + 4, challengelen);
+               memcpy(s->prompt, challenge, challengelen);
                strncpy(s->prompt + challengelen,
                        memchr(s->prompt, '\n', challengelen) ?
                        "" : "\r\nResponse: ",
@@ -2880,11 +3012,15 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            s->tried_publickey = 1;
            
            {
-               int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password);
+               const char *error = NULL;
+               int ret = loadrsakey(&ssh->cfg.keyfile, &s->key, s->password,
+                                    &error);
                if (ret == 0) {
                    c_write_str(ssh, "Couldn't load private key from ");
                    c_write_str(ssh, filename_to_str(&ssh->cfg.keyfile));
-                   c_write_str(ssh, ".\r\n");
+                   c_write_str(ssh, " (");
+                   c_write_str(ssh, error);
+                   c_write_str(ssh, ").\r\n");
                    continue;          /* go and try password */
                }
                if (ret == -1) {
@@ -2915,7 +3051,10 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                unsigned char buffer[32];
                Bignum challenge, response;
 
-               ssh1_read_bignum(ssh->pktin.body, &challenge);
+               if ((challenge = ssh1_pkt_getmp(ssh)) == NULL) {
+                   bombout(("Server's RSA challenge was badly formatted"));
+                   crStop(0);
+               }
                response = rsadecrypt(challenge, &s->key);
                freebn(s->key.private_exponent);/* burn the evidence */
 
@@ -3025,6 +3164,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    }
                    logevent("Sending password with camouflage packets");
                    ssh_pkt_defersend(ssh);
+                   sfree(randomstr);
                } 
                else if (!(ssh->remote_bugs & BUG_NEEDS_SSH1_PLAIN_PASSWORD)) {
                    /*
@@ -3290,6 +3430,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            } else {
                while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
                dport = dserv = -1;
+               ssh->portfwd_strptr++; /* eat the NUL and move to next one */
            }
            sport = atoi(sports);
            sserv = 0;
@@ -3370,11 +3511,19 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     }
 
     if (!ssh->cfg.nopty) {
+       /* Unpick the terminal-speed string. */
+       /* XXX perhaps we should allow no speeds to be sent. */
+       ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
+       sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
+       /* Send the pty request. */
        send_packet(ssh, SSH1_CMSG_REQUEST_PTY,
                    PKT_STR, ssh->cfg.termtype,
                    PKT_INT, ssh->term_height,
                    PKT_INT, ssh->term_width,
-                   PKT_INT, 0, PKT_INT, 0, PKT_CHAR, 0, PKT_END);
+                   PKT_INT, 0, PKT_INT, 0, /* width,height in pixels */
+                   PKT_CHAR, 192, PKT_INT, ssh->ispeed, /* TTY_OP_ISPEED */
+                   PKT_CHAR, 193, PKT_INT, ssh->ospeed, /* TTY_OP_OSPEED */
+                   PKT_CHAR, 0, PKT_END);
        ssh->state = SSH_STATE_INTERMED;
        do {
            crReturnV;
@@ -3387,7 +3536,8 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            c_write_str(ssh, "Server refused to allocate pty\r\n");
            ssh->editing = ssh->echoing = 1;
        }
-       logevent("Allocated pty");
+       logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
+                 ssh->ospeed, ssh->ispeed);
     } else {
        ssh->editing = ssh->echoing = 1;
     }
@@ -3448,11 +3598,19 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        if (ispkt) {
            if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
                ssh->pktin.type == SSH1_SMSG_STDERR_DATA) {
-               long len = GET_32BIT(ssh->pktin.body);
-               int bufsize =
+               char *string;
+               int stringlen, bufsize;
+
+               ssh_pkt_getstring(ssh, &string, &stringlen);
+               if (string == NULL) {
+                   bombout(("Incoming terminal data packet was badly formed"));
+                   crStopV;
+               }
+
+               bufsize =
                    from_backend(ssh->frontend,
                                 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
-                                (char *)(ssh->pktin.body) + 4, len);
+                                string, stringlen);
                if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
                    ssh->v1_stdout_throttling = 1;
                    ssh1_throttle(ssh, +1);
@@ -3465,12 +3623,13 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                /* Remote side is trying to open a channel to talk to our
                 * X-Server. Give them back a local channel number. */
                struct ssh_channel *c;
+               int remoteid = ssh_pkt_getuint32(ssh);
 
                logevent("Received X11 connect request");
                /* Refuse if X11 forwarding is disabled. */
                if (!ssh->X11_fwd_enabled) {
                    send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
-                               PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
+                               PKT_INT, remoteid, PKT_END);
                    logevent("Rejected X11 connect request");
                } else {
                    c = snew(struct ssh_channel);
@@ -3478,15 +3637,14 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
                    if (x11_init(&c->u.x11.s, ssh->cfg.x11_display, c,
                                 ssh->x11auth, NULL, -1, &ssh->cfg) != NULL) {
-                       logevent("opening X11 forward connection failed");
+                       logevent("Opening X11 forward connection failed");
                        sfree(c);
                        send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
-                                   PKT_INT, GET_32BIT(ssh->pktin.body),
-                                   PKT_END);
+                                   PKT_INT, remoteid, PKT_END);
                    } else {
                        logevent
-                           ("opening X11 forward connection succeeded");
-                       c->remoteid = GET_32BIT(ssh->pktin.body);
+                           ("Opening X11 forward connection succeeded");
+                       c->remoteid = remoteid;
                        c->localid = alloc_channel_id(ssh);
                        c->closes = 0;
                        c->v.v1.throttling = 0;
@@ -3502,15 +3660,16 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                /* Remote side is trying to open a channel to talk to our
                 * agent. Give them back a local channel number. */
                struct ssh_channel *c;
+               int remoteid = ssh_pkt_getuint32(ssh);
 
                /* Refuse if agent forwarding is disabled. */
                if (!ssh->agentfwd_enabled) {
                    send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
-                               PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
+                               PKT_INT, remoteid, PKT_END);
                } else {
                    c = snew(struct ssh_channel);
                    c->ssh = ssh;
-                   c->remoteid = GET_32BIT(ssh->pktin.body);
+                   c->remoteid = remoteid;
                    c->localid = alloc_channel_id(ssh);
                    c->closes = 0;
                    c->v.v1.throttling = 0;
@@ -3526,46 +3685,44 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                 * forwarded port. Give them back a local channel number. */
                struct ssh_channel *c;
                struct ssh_rportfwd pf;
+               int remoteid;
                int hostsize, port;
-               char host[256], buf[1024];
-               char *p, *h, *e;
+               char *host, buf[1024];
+               const char *e;
                c = snew(struct ssh_channel);
                c->ssh = ssh;
 
-               hostsize = GET_32BIT(ssh->pktin.body+4);
-               for (h = host, p = (char *)(ssh->pktin.body+8);
-                    hostsize != 0; hostsize--) {
-                   if (h+1 < host+sizeof(host))
-                       *h++ = *p;
-                   p++;
-               }
-               *h = 0;
-               port = GET_32BIT(p);
+               remoteid = ssh_pkt_getuint32(ssh);
+               ssh_pkt_getstring(ssh, &host, &hostsize);
+               port = ssh_pkt_getuint32(ssh);
 
-               strcpy(pf.dhost, host);
+               if (hostsize >= lenof(pf.dhost))
+                   hostsize = lenof(pf.dhost)-1;
+               memcpy(pf.dhost, host, hostsize);
+               pf.dhost[hostsize] = '\0';
                pf.dport = port;
 
                if (find234(ssh->rportfwds, &pf, NULL) == NULL) {
                    sprintf(buf, "Rejected remote port open request for %s:%d",
-                           host, port);
+                           pf.dhost, port);
                    logevent(buf);
                     send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
-                                PKT_INT, GET_32BIT(ssh->pktin.body), PKT_END);
+                                PKT_INT, remoteid, PKT_END);
                } else {
                    sprintf(buf, "Received remote port open request for %s:%d",
-                           host, port);
+                           pf.dhost, port);
                    logevent(buf);
-                   e = pfd_newconnect(&c->u.pfd.s, host, port, c, &ssh->cfg);
+                   e = pfd_newconnect(&c->u.pfd.s, pf.dhost, port,
+                                      c, &ssh->cfg);
                    if (e != NULL) {
                        char buf[256];
                        sprintf(buf, "Port open failed: %s", e);
                        logevent(buf);
                        sfree(c);
                        send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
-                                   PKT_INT, GET_32BIT(ssh->pktin.body),
-                                   PKT_END);
+                                   PKT_INT, remoteid, PKT_END);
                    } else {
-                       c->remoteid = GET_32BIT(ssh->pktin.body);
+                       c->remoteid = remoteid;
                        c->localid = alloc_channel_id(ssh);
                        c->closes = 0;
                        c->v.v1.throttling = 0;
@@ -3579,8 +3736,8 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                }
 
            } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_CONFIRMATION) {
-               unsigned int remoteid = GET_32BIT(ssh->pktin.body);
-               unsigned int localid = GET_32BIT(ssh->pktin.body+4);
+               unsigned int remoteid = ssh_pkt_getuint32(ssh);
+               unsigned int localid = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
 
                c = find234(ssh->channels, &remoteid, ssh_channelfind);
@@ -3603,7 +3760,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                }
 
            } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_OPEN_FAILURE) {
-               unsigned int remoteid = GET_32BIT(ssh->pktin.body);
+               unsigned int remoteid = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
 
                c = find234(ssh->channels, &remoteid, ssh_channelfind);
@@ -3617,7 +3774,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ||
                       ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE_CONFIRMATION) {
                /* Remote side closes a channel. */
-               unsigned i = GET_32BIT(ssh->pktin.body);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (c && ((int)c->remoteid) != -1) {
@@ -3658,19 +3815,22 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                }
            } else if (ssh->pktin.type == SSH1_MSG_CHANNEL_DATA) {
                /* Data sent down one of our channels. */
-               int i = GET_32BIT(ssh->pktin.body);
-               int len = GET_32BIT(ssh->pktin.body + 4);
-               unsigned char *p = ssh->pktin.body + 8;
+               int i = ssh_pkt_getuint32(ssh);
+               char *p;
+               int len;
                struct ssh_channel *c;
+
+               ssh_pkt_getstring(ssh, &p, &len);
+
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (c) {
                    int bufsize = 0;
                    switch (c->type) {
                      case CHAN_X11:
-                       bufsize = x11_send(c->u.x11.s, (char *)p, len);
+                       bufsize = x11_send(c->u.x11.s, p, len);
                        break;
                      case CHAN_SOCKDATA:
-                       bufsize = pfd_send(c->u.pfd.s, (char *)p, len);
+                       bufsize = pfd_send(c->u.pfd.s, p, len);
                        break;
                      case CHAN_AGENT:
                        /* Data for an agent message. Buffer it. */
@@ -3727,7 +3887,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                 * if no pty is available or in other odd cases. Ignore */
            } else if (ssh->pktin.type == SSH1_SMSG_EXIT_STATUS) {
                char buf[100];
-               ssh->exitcode = GET_32BIT(ssh->pktin.body);
+               ssh->exitcode = ssh_pkt_getuint32(ssh);
                sprintf(buf, "Server sent command exit status %d",
                        ssh->exitcode);
                logevent(buf);
@@ -4027,7 +4187,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        s->cscomp_tobe = NULL;
        s->sccomp_tobe = NULL;
        ssh->pktin.savedpos += 16;              /* skip garbage cookie */
-       ssh2_pkt_getstring(ssh, &str, &len);    /* key exchange algorithms */
+       ssh_pkt_getstring(ssh, &str, &len);    /* key exchange algorithms */
        for (i = 0; i < lenof(kex_algs); i++) {
            if (kex_algs[i] == &ssh_diffiehellman_gex &&
                (ssh->remote_bugs & BUG_SSH2_DH_GEX))
@@ -4037,14 +4197,14 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                break;
            }
        }
-       ssh2_pkt_getstring(ssh, &str, &len);    /* host key algorithms */
+       ssh_pkt_getstring(ssh, &str, &len);    /* host key algorithms */
        for (i = 0; i < lenof(hostkey_algs); i++) {
            if (in_commasep_string(hostkey_algs[i]->name, str, len)) {
                ssh->hostkey = hostkey_algs[i];
                break;
            }
        }
-       ssh2_pkt_getstring(ssh, &str, &len);    /* client->server cipher */
+       ssh_pkt_getstring(ssh, &str, &len);    /* client->server cipher */
        s->warn = 0;
        for (i = 0; i < s->n_preferred_ciphers; i++) {
            const struct ssh2_ciphers *c = s->preferred_ciphers[i];
@@ -4070,7 +4230,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            crStop(0);
        }
 
-       ssh2_pkt_getstring(ssh, &str, &len);    /* server->client cipher */
+       ssh_pkt_getstring(ssh, &str, &len);    /* server->client cipher */
        s->warn = 0;
        for (i = 0; i < s->n_preferred_ciphers; i++) {
            const struct ssh2_ciphers *c = s->preferred_ciphers[i];
@@ -4096,21 +4256,21 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            crStop(0);
        }
 
-       ssh2_pkt_getstring(ssh, &str, &len);    /* client->server mac */
+       ssh_pkt_getstring(ssh, &str, &len);    /* client->server mac */
        for (i = 0; i < s->nmacs; i++) {
            if (in_commasep_string(s->maclist[i]->name, str, len)) {
                s->csmac_tobe = s->maclist[i];
                break;
            }
        }
-       ssh2_pkt_getstring(ssh, &str, &len);    /* server->client mac */
+       ssh_pkt_getstring(ssh, &str, &len);    /* server->client mac */
        for (i = 0; i < s->nmacs; i++) {
            if (in_commasep_string(s->maclist[i]->name, str, len)) {
                s->scmac_tobe = s->maclist[i];
                break;
            }
        }
-       ssh2_pkt_getstring(ssh, &str, &len);  /* client->server compression */
+       ssh_pkt_getstring(ssh, &str, &len);  /* client->server compression */
        for (i = 0; i < lenof(compressions) + 1; i++) {
            const struct ssh_compress *c =
                i == 0 ? s->preferred_comp : compressions[i - 1];
@@ -4119,7 +4279,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                break;
            }
        }
-       ssh2_pkt_getstring(ssh, &str, &len);  /* server->client compression */
+       ssh_pkt_getstring(ssh, &str, &len);  /* server->client compression */
        for (i = 0; i < lenof(compressions) + 1; i++) {
            const struct ssh_compress *c =
                i == 0 ? s->preferred_comp : compressions[i - 1];
@@ -4194,9 +4354,9 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        bombout(("expected key exchange reply packet from server"));
        crStop(0);
     }
-    ssh2_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
+    ssh_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
     s->f = ssh2_pkt_getmp(ssh);
-    ssh2_pkt_getstring(ssh, &s->sigdata, &s->siglen);
+    ssh_pkt_getstring(ssh, &s->sigdata, &s->siglen);
 
     s->K = dh_find_K(ssh->kex_ctx, s->f);
 
@@ -4324,6 +4484,12 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     if (ssh->sccomp->text_name)
        logeventf(ssh, "Initialised %s decompression",
                  ssh->sccomp->text_name);
+    freebn(s->f);
+    freebn(s->K);
+    if (ssh->kex == &ssh_diffiehellman_gex) {
+       freebn(s->g);
+       freebn(s->p);
+    }
 
     /*
      * If this is the first key exchange phase, we must pass the
@@ -4577,7 +4743,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            if (keytype == SSH_KEYTYPE_SSH2) {
                s->publickey_blob =
                    ssh2_userkey_loadpub(&ssh->cfg.keyfile, NULL,
-                                        &s->publickey_bloblen);
+                                        &s->publickey_bloblen, NULL);
            } else {
                char *msgbuf;
                logeventf(ssh, "Unable to use this key file (%s)",
@@ -4611,7 +4777,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                 * output of (say) plink.)
                 */
                if (flags & (FLAG_VERBOSE | FLAG_INTERACTIVE)) {
-                   ssh2_pkt_getstring(ssh, &banner, &size);
+                   ssh_pkt_getstring(ssh, &banner, &size);
                    if (banner)
                        c_write_untrusted(ssh, banner, size);
                }
@@ -4650,7 +4816,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            if (ssh->pktin.type == SSH2_MSG_USERAUTH_FAILURE) {
                char *methods;
                int methlen;
-               ssh2_pkt_getstring(ssh, &methods, &methlen);
+               ssh_pkt_getstring(ssh, &methods, &methlen);
                s->kbd_inter_running = FALSE;
                if (!ssh2_pkt_getbool(ssh)) {
                    /*
@@ -4706,6 +4872,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
            s->method = 0;
            ssh->pkt_ctx &= ~SSH2_PKTCTX_AUTH_MASK;
+           s->need_pw = FALSE;
 
            /*
             * Most password/passphrase prompts will be
@@ -4885,6 +5052,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    if (s->authed)
                        continue;
                }
+               sfree(s->response);
            }
 
            if (!s->method && s->can_pubkey && s->publickey_blob
@@ -4907,7 +5075,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                pub_blob =
                    (unsigned char *)ssh2_userkey_loadpub(&ssh->cfg.keyfile,
                                                          &algorithm,
-                                                         &pub_blob_len);
+                                                         &pub_blob_len,
+                                                         NULL);
                if (pub_blob) {
                    ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
                    ssh2_pkt_addstring(ssh, s->username);
@@ -4941,9 +5110,11 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    } else {
                        s->need_pw = FALSE;
                    }
-                   c_write_str(ssh, "Authenticating with public key \"");
-                   c_write_str(ssh, comment);
-                   c_write_str(ssh, "\"\r\n");
+                   if (flags & FLAG_VERBOSE) {
+                       c_write_str(ssh, "Authenticating with public key \"");
+                       c_write_str(ssh, comment);
+                       c_write_str(ssh, "\"\r\n");
+                   }
                    s->method = AUTH_PUBLICKEY_FILE;
                }
            }
@@ -4994,9 +5165,9 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    char *name, *inst, *lang;
                    int name_len, inst_len, lang_len;
 
-                   ssh2_pkt_getstring(ssh, &name, &name_len);
-                   ssh2_pkt_getstring(ssh, &inst, &inst_len);
-                   ssh2_pkt_getstring(ssh, &lang, &lang_len);
+                   ssh_pkt_getstring(ssh, &name, &name_len);
+                   ssh_pkt_getstring(ssh, &inst, &inst_len);
+                   ssh_pkt_getstring(ssh, &lang, &lang_len);
                    if (name_len > 0) {
                        c_write_untrusted(ssh, name, name_len);
                        c_write_str(ssh, "\r\n");
@@ -5005,7 +5176,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                        c_write_untrusted(ssh, inst, inst_len);
                        c_write_str(ssh, "\r\n");
                    }
-                   s->num_prompts = ssh2_pkt_getuint32(ssh);
+                   s->num_prompts = ssh_pkt_getuint32(ssh);
                }
 
                /*
@@ -5016,7 +5187,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    char *prompt;
                    int prompt_len;
 
-                   ssh2_pkt_getstring(ssh, &prompt, &prompt_len);
+                   ssh_pkt_getstring(ssh, &prompt, &prompt_len);
                    if (prompt_len > 0) {
                        strncpy(s->pwprompt, prompt, sizeof(s->pwprompt));
                        s->pwprompt[prompt_len < sizeof(s->pwprompt) ?
@@ -5084,14 +5255,18 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                 * We have our passphrase. Now try the actual authentication.
                 */
                struct ssh2_userkey *key;
+               const char *error = NULL;
 
-               key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password);
+               key = ssh2_load_userkey(&ssh->cfg.keyfile, s->password,
+                                       &error);
                if (key == SSH2_WRONG_PASSPHRASE || key == NULL) {
                    if (key == SSH2_WRONG_PASSPHRASE) {
                        c_write_str(ssh, "Wrong passphrase\r\n");
                        s->tried_pubkey_config = FALSE;
                    } else {
-                       c_write_str(ssh, "Unable to load private key\r\n");
+                       c_write_str(ssh, "Unable to load private key (");
+                       c_write_str(ssh, error);
+                       c_write_str(ssh, ")\r\n");
                        s->tried_pubkey_config = TRUE;
                    }
                    /* Send a spurious AUTH_NONE to return to the top. */
@@ -5153,6 +5328,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
                    ssh2_pkt_send(ssh);
                    s->type = AUTH_TYPE_PUBLICKEY;
+                   key->alg->freekey(key->data);
                }
            } else if (s->method == AUTH_PASSWORD) {
                /*
@@ -5280,15 +5456,15 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        crStopV;
        /* FIXME: error data comes back in FAILURE packet */
     }
-    if (ssh2_pkt_getuint32(ssh) != ssh->mainchan->localid) {
+    if (ssh_pkt_getuint32(ssh) != ssh->mainchan->localid) {
        bombout(("Server's channel confirmation cited wrong channel"));
        crStopV;
     }
-    ssh->mainchan->remoteid = ssh2_pkt_getuint32(ssh);
+    ssh->mainchan->remoteid = ssh_pkt_getuint32(ssh);
     ssh->mainchan->type = CHAN_MAINSESSION;
     ssh->mainchan->closes = 0;
-    ssh->mainchan->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
-    ssh->mainchan->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
+    ssh->mainchan->v.v2.remwindow = ssh_pkt_getuint32(ssh);
+    ssh->mainchan->v.v2.remmaxpkt = ssh_pkt_getuint32(ssh);
     bufchain_init(&ssh->mainchan->v.v2.outbuffer);
     add234(ssh->channels, ssh->mainchan);
     logevent("Opened channel for session");
@@ -5315,12 +5491,12 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        do {
            crWaitUntilV(ispkt);
            if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
                    continue;          /* nonexistent channel */
-               c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
+               c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
            }
        } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
 
@@ -5400,6 +5576,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            } else {
                while (*ssh->portfwd_strptr) ssh->portfwd_strptr++;
                dport = dserv = -1;
+               ssh->portfwd_strptr++; /* eat the NUL and move to next one */
            }
            sport = atoi(sports);
            sserv = 0;
@@ -5470,12 +5647,12 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                        do {
                            crWaitUntilV(ispkt);
                            if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
-                               unsigned i = ssh2_pkt_getuint32(ssh);
+                               unsigned i = ssh_pkt_getuint32(ssh);
                                struct ssh_channel *c;
                                c = find234(ssh->channels, &i, ssh_channelfind);
                                if (!c)
                                    continue;/* nonexistent channel */
-                               c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
+                               c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
                            }
                        } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
 
@@ -5510,12 +5687,12 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        do {
            crWaitUntilV(ispkt);
            if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
                    continue;          /* nonexistent channel */
-               c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
+               c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
            }
        } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
 
@@ -5536,6 +5713,11 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
      * Now allocate a pty for the session.
      */
     if (!ssh->cfg.nopty) {
+       /* Unpick the terminal-speed string. */
+       /* XXX perhaps we should allow no speeds to be sent. */
+        ssh->ospeed = 38400; ssh->ispeed = 38400; /* last-resort defaults */
+       sscanf(ssh->cfg.termspeed, "%d,%d", &ssh->ospeed, &ssh->ispeed);
+       /* Build the pty request. */
        ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
        ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);       /* recipient channel */
        ssh2_pkt_addstring(ssh, "pty-req");
@@ -5546,19 +5728,23 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        ssh2_pkt_adduint32(ssh, 0);            /* pixel width */
        ssh2_pkt_adduint32(ssh, 0);            /* pixel height */
        ssh2_pkt_addstring_start(ssh);
-       ssh2_pkt_addstring_data(ssh, "\0", 1);  /* TTY_OP_END, no special options */
+       ssh2_pkt_addbyte(ssh, 128);            /* TTY_OP_ISPEED */
+       ssh2_pkt_adduint32(ssh, ssh->ispeed);
+       ssh2_pkt_addbyte(ssh, 129);            /* TTY_OP_OSPEED */
+       ssh2_pkt_adduint32(ssh, ssh->ospeed);
+       ssh2_pkt_addstring_data(ssh, "\0", 1); /* TTY_OP_END */
        ssh2_pkt_send(ssh);
        ssh->state = SSH_STATE_INTERMED;
 
        do {
            crWaitUntilV(ispkt);
            if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
                    continue;          /* nonexistent channel */
-               c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
+               c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
            }
        } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
 
@@ -5571,7 +5757,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
            c_write_str(ssh, "Server refused to allocate pty\r\n");
            ssh->editing = ssh->echoing = 1;
        } else {
-           logevent("Allocated pty");
+           logeventf(ssh, "Allocated pty (ospeed %dbps, ispeed %dbps)",
+                     ssh->ospeed, ssh->ispeed);
        }
     } else {
        ssh->editing = ssh->echoing = 1;
@@ -5612,12 +5799,12 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
        do {
            crWaitUntilV(ispkt);
            if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
                    continue;          /* nonexistent channel */
-               c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
+               c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
            }
        } while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
        if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
@@ -5665,15 +5852,15 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA) {
                char *data;
                int length;
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
                    continue;          /* nonexistent channel */
                if (ssh->pktin.type == SSH2_MSG_CHANNEL_EXTENDED_DATA &&
-                   ssh2_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
+                   ssh_pkt_getuint32(ssh) != SSH2_EXTENDED_DATA_STDERR)
                    continue;          /* extended but not stderr */
-               ssh2_pkt_getstring(ssh, &data, &length);
+               ssh_pkt_getstring(ssh, &data, &length);
                if (data) {
                    int bufsize = 0;
                    c->v.v2.locwindow -= length;
@@ -5740,7 +5927,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                        ssh2_set_window(c, OUR_V2_WINSIZE - bufsize);
                }
            } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_EOF) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
 
                c = find234(ssh->channels, &i, ssh_channelfind);
@@ -5761,7 +5948,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    sshfwd_close(c);
                }
            } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_CLOSE) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
 
                c = find234(ssh->channels, &i, ssh_channelfind);
@@ -5825,25 +6012,25 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                }
                continue;              /* remote sends close; ignore (FIXME) */
            } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c || c->closes)
                    continue;          /* nonexistent or closing channel */
-               c->v.v2.remwindow += ssh2_pkt_getuint32(ssh);
+               c->v.v2.remwindow += ssh_pkt_getuint32(ssh);
                s->try_send = TRUE;
            } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
                    continue;          /* nonexistent channel */
                if (c->type != CHAN_SOCKDATA_DORMANT)
                    continue;          /* dunno why they're confirming this */
-               c->remoteid = ssh2_pkt_getuint32(ssh);
+               c->remoteid = ssh_pkt_getuint32(ssh);
                c->type = CHAN_SOCKDATA;
-               c->v.v2.remwindow = ssh2_pkt_getuint32(ssh);
-               c->v.v2.remmaxpkt = ssh2_pkt_getuint32(ssh);
+               c->v.v2.remwindow = ssh_pkt_getuint32(ssh);
+               c->v.v2.remmaxpkt = ssh_pkt_getuint32(ssh);
                if (c->u.pfd.s)
                    pfd_confirm(c->u.pfd.s);
                if (c->closes) {
@@ -5858,7 +6045,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    ssh2_pkt_send(ssh);
                }
            } else if (ssh->pktin.type == SSH2_MSG_CHANNEL_OPEN_FAILURE) {
-               unsigned i = ssh2_pkt_getuint32(ssh);
+               unsigned i = ssh_pkt_getuint32(ssh);
                struct ssh_channel *c;
                c = find234(ssh->channels, &i, ssh_channelfind);
                if (!c)
@@ -5878,8 +6065,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                int typelen, want_reply;
                struct ssh_channel *c;
 
-               localid = ssh2_pkt_getuint32(ssh);
-               ssh2_pkt_getstring(ssh, &type, &typelen);
+               localid = ssh_pkt_getuint32(ssh);
+               ssh_pkt_getstring(ssh, &type, &typelen);
                want_reply = ssh2_pkt_getbool(ssh);
 
                /*
@@ -5911,7 +6098,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    c == ssh->mainchan) {
                    /* We recognise "exit-status" on the primary channel. */
                    char buf[100];
-                   ssh->exitcode = ssh2_pkt_getuint32(ssh);
+                   ssh->exitcode = ssh_pkt_getuint32(ssh);
                    sprintf(buf, "Server sent command exit status %d",
                            ssh->exitcode);
                    logevent(buf);
@@ -5937,7 +6124,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                char *type;
                int typelen, want_reply;
 
-               ssh2_pkt_getstring(ssh, &type, &typelen);
+               ssh_pkt_getstring(ssh, &type, &typelen);
                want_reply = ssh2_pkt_getbool(ssh);
 
                 /*
@@ -5959,22 +6146,22 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                char *error = NULL;
                struct ssh_channel *c;
                unsigned remid, winsize, pktsize;
-               ssh2_pkt_getstring(ssh, &type, &typelen);
+               ssh_pkt_getstring(ssh, &type, &typelen);
                c = snew(struct ssh_channel);
                c->ssh = ssh;
 
-               remid = ssh2_pkt_getuint32(ssh);
-               winsize = ssh2_pkt_getuint32(ssh);
-               pktsize = ssh2_pkt_getuint32(ssh);
+               remid = ssh_pkt_getuint32(ssh);
+               winsize = ssh_pkt_getuint32(ssh);
+               pktsize = ssh_pkt_getuint32(ssh);
 
                if (typelen == 3 && !memcmp(type, "x11", 3)) {
                    char *addrstr;
 
-                    ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
+                    ssh_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
                    addrstr = snewn(peeraddrlen+1, char);
                    memcpy(addrstr, peeraddr, peeraddrlen);
                    peeraddr[peeraddrlen] = '\0';
-                    peerport = ssh2_pkt_getuint32(ssh);
+                    peerport = ssh_pkt_getuint32(ssh);
 
                    if (!ssh->X11_fwd_enabled)
                        error = "X11 forwarding is not enabled";
@@ -5992,16 +6179,18 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                    struct ssh_rportfwd pf, *realpf;
                    char *dummy;
                    int dummylen;
-                   ssh2_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
-                   pf.sport = ssh2_pkt_getuint32(ssh);
-                    ssh2_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
-                    peerport = ssh2_pkt_getuint32(ssh);
+                   ssh_pkt_getstring(ssh, &dummy, &dummylen);/* skip address */
+                   pf.sport = ssh_pkt_getuint32(ssh);
+                    ssh_pkt_getstring(ssh, &peeraddr, &peeraddrlen);
+                    peerport = ssh_pkt_getuint32(ssh);
                    realpf = find234(ssh->rportfwds, &pf, NULL);
                    if (realpf == NULL) {
                        error = "Remote port is not recognised";
                    } else {
-                       char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
-                                                realpf->dport, c, &ssh->cfg);
+                       const char *e = pfd_newconnect(&c->u.pfd.s,
+                                                      realpf->dhost,
+                                                      realpf->dport, c,
+                                                      &ssh->cfg);
                        logeventf(ssh, "Received remote port open request"
                                  " for %s:%d", realpf->dhost, realpf->dport);
                        if (e != NULL) {
@@ -6110,11 +6299,12 @@ static void ssh2_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
  *
  * Returns an error message, or NULL on success.
  */
-static char *ssh_init(void *frontend_handle, void **backend_handle,
-                     Config *cfg,
-                     char *host, int port, char **realhost, int nodelay)
+static const char *ssh_init(void *frontend_handle, void **backend_handle,
+                           Config *cfg,
+                           char *host, int port, char **realhost, int nodelay,
+                           int keepalive)
 {
-    char *p;
+    const char *p;
     Ssh ssh;
 
     ssh = snew(struct ssh_tag);
@@ -6196,7 +6386,7 @@ static char *ssh_init(void *frontend_handle, void **backend_handle,
 
     ssh->protocol = NULL;
 
-    p = connect_to_host(ssh, host, port, realhost, nodelay);
+    p = connect_to_host(ssh, host, port, realhost, nodelay, keepalive);
     if (p != NULL)
        return p;
 
@@ -6219,10 +6409,18 @@ static void ssh_free(void *handle)
        ssh->csmac->free_context(ssh->cs_mac_ctx);
     if (ssh->sc_mac_ctx)
        ssh->scmac->free_context(ssh->sc_mac_ctx);
-    if (ssh->cs_comp_ctx)
-       ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
-    if (ssh->sc_comp_ctx)
-       ssh->sccomp->compress_cleanup(ssh->sc_comp_ctx);
+    if (ssh->cs_comp_ctx) {
+       if (ssh->cscomp)
+           ssh->cscomp->compress_cleanup(ssh->cs_comp_ctx);
+       else
+           zlib_compress_cleanup(ssh->cs_comp_ctx);
+    }
+    if (ssh->sc_comp_ctx) {
+       if (ssh->sccomp)
+           ssh->sccomp->decompress_cleanup(ssh->sc_comp_ctx);
+       else
+           zlib_decompress_cleanup(ssh->sc_comp_ctx);
+    }
     if (ssh->kex_ctx)
        dh_cleanup(ssh->kex_ctx);
     sfree(ssh->savedhost);
@@ -6256,7 +6454,22 @@ static void ssh_free(void *handle)
     sfree(ssh->do_ssh1_login_state);
     sfree(ssh->do_ssh2_transport_state);
     sfree(ssh->do_ssh2_authconn_state);
-    
+    if (ssh->pktout.data) {
+       sfree(ssh->pktout.data);
+       ssh->pktout.data = NULL;
+    }
+    if (ssh->pktin.data) {
+       sfree(ssh->pktin.data);
+       ssh->pktin.data = NULL;
+    }
+    if (ssh->crcda_ctx) {
+       crcda_free_context(ssh->crcda_ctx);
+       ssh->crcda_ctx = NULL;
+    }
+    if (ssh->logctx) {
+       log_free(ssh->logctx);
+       ssh->logctx = NULL;
+    }
     if (ssh->s)
        ssh_do_close(ssh);
     sfree(ssh);