X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/6b78788aeda49ad942a13e736cda2cf282432d78..70e5d0fd16d26307b670972cdfd2a12c21a06572:/ssh.c?ds=sidebyside

diff --git a/ssh.c b/ssh.c
index 59726ae5..442d35a3 100644
--- a/ssh.c
+++ b/ssh.c
@@ -1,4 +1,3 @@
-#include <windows.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
@@ -15,26 +14,6 @@
 #define TRUE 1
 #endif
 
-#define logevent(s) { logevent(s); \
-                      if ((flags & FLAG_STDERR) && (flags & FLAG_VERBOSE)) \
-                      { fprintf(stderr, "%s\n", s); fflush(stderr); } }
-
-/* logevent, only printf-formatted. */
-void logeventf(char *fmt, ...)
-{
-    va_list ap;
-    char stuff[200];
-
-    va_start(ap, fmt);
-    vsprintf(stuff, fmt, ap);
-    va_end(ap);
-    logevent(stuff);
-}
-
-#define bombout(msg) ( ssh->state = SSH_STATE_CLOSED, \
-                          (ssh->s ? sk_close(ssh->s), ssh->s = NULL : 0), \
-                          logeventf msg, connection_fatal msg )
-
 #define SSH1_MSG_DISCONNECT                       1	/* 0x1 */
 #define SSH1_SMSG_PUBLIC_KEY                      2	/* 0x2 */
 #define SSH1_CMSG_SESSION_KEY                     3	/* 0x3 */
@@ -312,16 +291,17 @@ enum { PKT_END, PKT_INT, PKT_CHAR, PKT_DATA, PKT_STR, PKT_BIGNUM };
 
 typedef struct ssh_tag *Ssh;
 
-extern char *x11_init(Socket *, char *, void *);
+extern char *x11_init(Socket *, char *, void *, void *);
 extern void x11_close(Socket);
 extern int x11_send(Socket, char *, int);
-extern void x11_invent_auth(char *, int, char *, int);
+extern void *x11_invent_auth(char *, int, char *, int);
 extern void x11_unthrottle(Socket s);
 extern void x11_override_throttle(Socket s, int enable);
+extern int x11_get_screen_number(char *display);
 
 extern char *pfd_newconnect(Socket * s, char *hostname, int port, void *c);
-extern char *pfd_addforward(char *desthost, int destport, int port,
-			    void *backhandle);
+extern char *pfd_addforward(char *desthost, int destport, char *srcaddr,
+			    int port, void *backhandle);
 extern void pfd_close(Socket s);
 extern int pfd_send(Socket s, char *data, int len);
 extern void pfd_confirm(Socket s);
@@ -335,7 +315,7 @@ static void ssh2_pkt_addstring_start(Ssh);
 static void ssh2_pkt_addstring_str(Ssh, char *data);
 static void ssh2_pkt_addstring_data(Ssh, char *data, int len);
 static void ssh2_pkt_addstring(Ssh, char *data);
-static char *ssh2_mpint_fmt(Bignum b, int *len);
+static unsigned char *ssh2_mpint_fmt(Bignum b, int *len);
 static void ssh2_pkt_addmp(Ssh, Bignum b);
 static int ssh2_pkt_construct(Ssh);
 static void ssh2_pkt_send(Ssh);
@@ -557,6 +537,7 @@ struct ssh_tag {
     Socket s;
 
     void *ldisc;
+    void *logctx;
 
     unsigned char session_key[32];
     int v1_compressing;
@@ -628,6 +609,8 @@ struct ssh_tag {
     char *portfwd_strptr;
     int pkt_ctx;
 
+    void *x11auth;
+
     int version;
     int v1_throttle_count;
     int overall_bufsize;
@@ -656,6 +639,25 @@ struct ssh_tag {
     int (*s_rdpkt) (Ssh ssh, unsigned char **data, int *datalen);
 };
 
+#define logevent(s) logevent(ssh->frontend, s)
+
+/* logevent, only printf-formatted. */
+void logeventf(Ssh ssh, char *fmt, ...)
+{
+    va_list ap;
+    char *buf;
+
+    va_start(ap, fmt);
+    buf = dupvprintf(fmt, ap);
+    va_end(ap);
+    logevent(buf);
+    sfree(buf);
+}
+
+#define bombout(msg) ( ssh->state = SSH_STATE_CLOSED, \
+                          (ssh->s ? sk_close(ssh->s), ssh->s = NULL : 0), \
+                          logeventf msg, connection_fatal msg )
+
 static int ssh_channelcmp(void *av, void *bv)
 {
     struct ssh_channel *a = (struct ssh_channel *) av;
@@ -821,7 +823,7 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
 
     if (ssh->cipher && detect_attack(ssh->crcda_ctx, ssh->pktin.data,
 				     st->biglen, NULL)) {
-        bombout(("Network attack (CRC compensation) detected!"));
+        bombout((ssh,"Network attack (CRC compensation) detected!"));
         crReturn(0);
     }
 
@@ -831,7 +833,7 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
     st->realcrc = crc32(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"));
+	bombout((ssh,"Incorrect CRC received on packet"));
 	crReturn(0);
     }
 
@@ -858,8 +860,11 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
 
     ssh->pktin.type = ssh->pktin.body[-1];
 
-    log_packet(PKT_INCOMING, ssh->pktin.type, ssh1_pkt_type(ssh->pktin.type),
-	       ssh->pktin.body, ssh->pktin.length);
+    if (ssh->logctx)
+	log_packet(ssh->logctx,
+		   PKT_INCOMING, ssh->pktin.type,
+		   ssh1_pkt_type(ssh->pktin.type),
+		   ssh->pktin.body, ssh->pktin.length);
 
     if (ssh->pktin.type == SSH1_SMSG_STDOUT_DATA ||
 	ssh->pktin.type == SSH1_SMSG_STDERR_DATA ||
@@ -868,7 +873,7 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
 	ssh->pktin.type == SSH1_SMSG_AUTH_CCARD_CHALLENGE) {
 	long stringlen = GET_32BIT(ssh->pktin.body);
 	if (stringlen + 4 != ssh->pktin.length) {
-	    bombout(("Received data packet with bogus string length"));
+	    bombout((ssh,"Received data packet with bogus string length"));
 	    crReturn(0);
 	}
     }
@@ -901,7 +906,7 @@ static int ssh1_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
 	memcpy(buf + nowlen, ssh->pktin.body + 4, msglen);
 	buf[nowlen + msglen] = '\0';
 	/* logevent(buf); (this is now done within the bombout macro) */
-	bombout(("Server sent disconnect message:\n\"%s\"", buf+nowlen));
+	bombout((ssh,"Server sent disconnect message:\n\"%s\"", buf+nowlen));
 	crReturn(0);
     }
 
@@ -955,7 +960,7 @@ static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
      * do us any more damage.
      */
     if (st->len < 0 || st->pad < 0 || st->len + st->pad < 0) {
-	bombout(("Incoming packet was garbled on decryption"));
+	bombout((ssh,"Incoming packet was garbled on decryption"));
 	crReturn(0);
     }
 
@@ -1003,7 +1008,7 @@ static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
     if (ssh->scmac
 	&& !ssh->scmac->verify(ssh->sc_mac_ctx, ssh->pktin.data, st->len + 4,
 			       st->incoming_sequence)) {
-	bombout(("Incorrect MAC received on packet"));
+	bombout((ssh,"Incorrect MAC received on packet"));
 	crReturn(0);
     }
     st->incoming_sequence++;	       /* whether or not we MACed */
@@ -1032,9 +1037,10 @@ static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
     ssh->pktin.savedpos = 6;
     ssh->pktin.type = ssh->pktin.data[5];
 
-    log_packet(PKT_INCOMING, ssh->pktin.type,
-	       ssh2_pkt_type(ssh->pkt_ctx, ssh->pktin.type),
-	       ssh->pktin.data+6, ssh->pktin.length-6);
+    if (ssh->logctx)
+	log_packet(ssh->logctx, PKT_INCOMING, ssh->pktin.type,
+		   ssh2_pkt_type(ssh->pkt_ctx, ssh->pktin.type),
+		   ssh->pktin.data+6, ssh->pktin.length-6);
 
     switch (ssh->pktin.type) {
         /*
@@ -1043,30 +1049,29 @@ static int ssh2_rdpkt(Ssh ssh, unsigned char **data, int *datalen)
       case SSH2_MSG_DISCONNECT:
         {
             /* log reason code in disconnect message */
-            char buf[256];
+            char *buf;
+	    int nowlen;
             int reason = GET_32BIT(ssh->pktin.data + 6);
             unsigned msglen = GET_32BIT(ssh->pktin.data + 10);
-            unsigned nowlen;
+
             if (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) {
-                sprintf(buf, "Received disconnect message (%s)",
-                        ssh2_disconnect_reasons[reason]);
+                buf = dupprintf("Received disconnect message (%s)",
+				ssh2_disconnect_reasons[reason]);
             } else {
-                sprintf(buf, "Received disconnect message (unknown type %d)",
-                        reason);
+                buf = dupprintf("Received disconnect message (unknown"
+				" type %d)", reason);
             }
             logevent(buf);
-            strcpy(buf, "Disconnection message text: ");
-            nowlen = strlen(buf);
-            if (msglen > sizeof(buf) - nowlen - 1)
-                msglen = sizeof(buf) - nowlen - 1;
-            memcpy(buf + nowlen, ssh->pktin.data + 14, msglen);
-            buf[nowlen + msglen] = '\0';
+	    sfree(buf);
+            buf = dupprintf("Disconnection message text: %n%.*s",
+			    &nowlen, msglen, ssh->pktin.data + 14);
             logevent(buf);
-            bombout(("Server sent disconnect message\ntype %d (%s):\n\"%s\"",
+            bombout((ssh,"Server sent disconnect message\ntype %d (%s):\n\"%s\"",
                      reason,
                      (reason > 0 && reason < lenof(ssh2_disconnect_reasons)) ?
                      ssh2_disconnect_reasons[reason] : "unknown",
                      buf+nowlen));
+	    sfree(buf);
             crReturn(0);
         }
         break;
@@ -1175,8 +1180,10 @@ static int s_wrpkt_prepare(Ssh ssh)
 
     ssh->pktout.body[-1] = ssh->pktout.type;
 
-    log_packet(PKT_OUTGOING, ssh->pktout.type, ssh1_pkt_type(ssh->pktout.type),
-	       ssh->pktout.body, ssh->pktout.length);
+    if (ssh->logctx)
+	log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.type,
+		   ssh1_pkt_type(ssh->pktout.type),
+		   ssh->pktout.body, ssh->pktout.length);
 
     if (ssh->v1_compressing) {
 	unsigned char *compblk;
@@ -1209,7 +1216,7 @@ static void s_wrpkt(Ssh ssh)
 {
     int len, backlog;
     len = s_wrpkt_prepare(ssh);
-    backlog = sk_write(ssh->s, ssh->pktout.data, len);
+    backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
     if (backlog > SSH_MAX_BACKLOG)
 	ssh_throttle_all(ssh, 1, backlog);
 }
@@ -1245,7 +1252,7 @@ static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
 	    pktlen += 4;
 	    break;
 	  case PKT_CHAR:
-	    (void) va_arg(ap1, char);
+	    (void) va_arg(ap1, int);
 	    pktlen++;
 	    break;
 	  case PKT_DATA:
@@ -1255,7 +1262,7 @@ static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
 	    break;
 	  case PKT_STR:
 	    argp = va_arg(ap1, unsigned char *);
-	    arglen = strlen(argp);
+	    arglen = strlen((char *)argp);
 	    pktlen += 4 + arglen;
 	    break;
 	  case PKT_BIGNUM:
@@ -1278,7 +1285,7 @@ static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
 	    p += 4;
 	    break;
 	  case PKT_CHAR:
-	    argchar = va_arg(ap2, unsigned char);
+	    argchar = (unsigned char) va_arg(ap2, int);
 	    *p = argchar;
 	    p++;
 	    break;
@@ -1290,7 +1297,7 @@ static void construct_packet(Ssh ssh, int pkttype, va_list ap1, va_list ap2)
 	    break;
 	  case PKT_STR:
 	    argp = va_arg(ap2, unsigned char *);
-	    arglen = strlen(argp);
+	    arglen = strlen((char *)argp);
 	    PUT_32BIT(p, arglen);
 	    memcpy(p + 4, argp, arglen);
 	    p += 4 + arglen;
@@ -1421,7 +1428,7 @@ static void ssh2_pkt_addstring(Ssh ssh, char *data)
     ssh2_pkt_addstring_start(ssh);
     ssh2_pkt_addstring_str(ssh, data);
 }
-static char *ssh2_mpint_fmt(Bignum b, int *len)
+static unsigned char *ssh2_mpint_fmt(Bignum b, int *len)
 {
     unsigned char *p;
     int i, n = (bignum_bitcount(b) + 7) / 8;
@@ -1444,7 +1451,7 @@ static void ssh2_pkt_addmp(Ssh ssh, Bignum b)
     int len;
     p = ssh2_mpint_fmt(b, &len);
     ssh2_pkt_addstring_start(ssh);
-    ssh2_pkt_addstring_data(ssh, p, len);
+    ssh2_pkt_addstring_data(ssh, (char *)p, len);
     sfree(p);
 }
 
@@ -1457,9 +1464,10 @@ static int ssh2_pkt_construct(Ssh ssh)
 {
     int cipherblk, maclen, padding, i;
 
-    log_packet(PKT_OUTGOING, ssh->pktout.data[5],
-	       ssh2_pkt_type(ssh->pkt_ctx, ssh->pktout.data[5]),
-	       ssh->pktout.data + 6, ssh->pktout.length - 6);
+    if (ssh->logctx)
+	log_packet(ssh->logctx, PKT_OUTGOING, ssh->pktout.data[5],
+		   ssh2_pkt_type(ssh->pkt_ctx, ssh->pktout.data[5]),
+		   ssh->pktout.data + 6, ssh->pktout.length - 6);
 
     /*
      * Compress packet payload.
@@ -1514,7 +1522,7 @@ static void ssh2_pkt_send(Ssh ssh)
     int len;
     int backlog;
     len = ssh2_pkt_construct(ssh);
-    backlog = sk_write(ssh->s, ssh->pktout.data, len);
+    backlog = sk_write(ssh->s, (char *)ssh->pktout.data, len);
     if (backlog > SSH_MAX_BACKLOG)
 	ssh_throttle_all(ssh, 1, backlog);
 }
@@ -1549,7 +1557,8 @@ static void ssh2_pkt_defer(Ssh ssh)
 static void ssh_pkt_defersend(Ssh ssh)
 {
     int backlog;
-    backlog = sk_write(ssh->s, ssh->deferred_send_data, ssh->deferred_len);
+    backlog = sk_write(ssh->s, (char *)ssh->deferred_send_data,
+		       ssh->deferred_len);
     ssh->deferred_len = ssh->deferred_size = 0;
     sfree(ssh->deferred_send_data);
     ssh->deferred_send_data = NULL;
@@ -1603,15 +1612,19 @@ static int ssh2_pkt_getbool(Ssh ssh)
 }
 static void ssh2_pkt_getstring(Ssh ssh, char **p, int *length)
 {
+    int len;
     *p = NULL;
     *length = 0;
     if (ssh->pktin.length - ssh->pktin.savedpos < 4)
 	return;
-    *length = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
+    len = GET_32BIT(ssh->pktin.data + ssh->pktin.savedpos);
+    if (len < 0)
+	return;
+    *length = len;
     ssh->pktin.savedpos += 4;
     if (ssh->pktin.length - ssh->pktin.savedpos < *length)
 	return;
-    *p = ssh->pktin.data + ssh->pktin.savedpos;
+    *p = (char *)(ssh->pktin.data + ssh->pktin.savedpos);
     ssh->pktin.savedpos += *length;
 }
 static Bignum ssh2_pkt_getmp(Ssh ssh)
@@ -1624,10 +1637,10 @@ static Bignum ssh2_pkt_getmp(Ssh ssh)
     if (!p)
 	return NULL;
     if (p[0] & 0x80) {
-	bombout(("internal error: Can't handle negative mpints"));
+	bombout((ssh,"internal error: Can't handle negative mpints"));
 	return NULL;
     }
-    b = bignum_from_bytes(p, length);
+    b = bignum_from_bytes((unsigned char *)p, length);
     return b;
 }
 
@@ -1677,18 +1690,18 @@ static void ssh2_add_sigblob(Ssh ssh, void *pkblob_v, int pkblob_len,
 	if (len != siglen) {
 	    unsigned char newlen[4];
 	    ssh2_pkt_addstring_start(ssh);
-	    ssh2_pkt_addstring_data(ssh, sigblob, pos);
+	    ssh2_pkt_addstring_data(ssh, (char *)sigblob, pos);
 	    /* dmemdump(sigblob, pos); */
 	    pos += 4;		       /* point to start of actual sig */
 	    PUT_32BIT(newlen, len);
-	    ssh2_pkt_addstring_data(ssh, newlen, 4);
+	    ssh2_pkt_addstring_data(ssh, (char *)newlen, 4);
 	    /* dmemdump(newlen, 4); */
 	    newlen[0] = 0;
 	    while (len-- > siglen) {
-		ssh2_pkt_addstring_data(ssh, newlen, 1);
+		ssh2_pkt_addstring_data(ssh, (char *)newlen, 1);
 		/* dmemdump(newlen, 1); */
 	    }
-	    ssh2_pkt_addstring_data(ssh, sigblob+pos, siglen);
+	    ssh2_pkt_addstring_data(ssh, (char *)(sigblob+pos), siglen);
 	    /* dmemdump(sigblob+pos, siglen); */
 	    return;
 	}
@@ -1697,7 +1710,7 @@ static void ssh2_add_sigblob(Ssh ssh, void *pkblob_v, int pkblob_len,
     }
 
     ssh2_pkt_addstring_start(ssh);
-    ssh2_pkt_addstring_data(ssh, sigblob, sigblob_len);
+    ssh2_pkt_addstring_data(ssh, (char *)sigblob, sigblob_len);
 }
 
 /*
@@ -1755,9 +1768,9 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (cfg.sshbug_hmac2 == BUG_ON ||
 	(cfg.sshbug_hmac2 == BUG_AUTO &&
-	 (!strncmp(imp, "2.1.0", 5) || !strncmp(imp, "2.0.", 4) ||
-	  !strncmp(imp, "2.2.0", 5) || !strncmp(imp, "2.3.0", 5) ||
-	  !strncmp(imp, "2.1 ", 4)))) {
+	 (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)))) {
 	/*
 	 * These versions have the HMAC bug.
 	 */
@@ -1767,7 +1780,7 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (cfg.sshbug_derivekey2 == BUG_ON ||
 	(cfg.sshbug_derivekey2 == BUG_AUTO &&
-	 (!strncmp(imp, "2.0.", 4)))) {
+	 (wc_match("2.0.0*", imp) || wc_match("2.0.1[01]*", imp) ))) {
 	/*
 	 * These versions have the key-derivation bug (failing to
 	 * include the literal shared secret in the hashes that
@@ -1779,8 +1792,8 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (cfg.sshbug_rsapad2 == BUG_ON ||
 	(cfg.sshbug_rsapad2 == BUG_AUTO &&
-	 ((!strncmp(imp, "OpenSSH_2.", 10) && imp[10]>='5' && imp[10]<='9') ||
-	  (!strncmp(imp, "OpenSSH_3.", 10) && imp[10]>='0' && imp[10]<='2')))){
+	 (wc_match("OpenSSH_2.[5-9]*", imp) ||
+	  wc_match("OpenSSH_3.[0-2]*", imp)))) {
 	/*
 	 * These versions have the SSH2 RSA padding bug.
 	 */
@@ -1790,7 +1803,7 @@ static void ssh_detect_bugs(Ssh ssh, char *vstring)
 
     if (cfg.sshbug_dhgex2 == BUG_ON) {
 	/*
-	 * These versions have the SSH2 DH GEX bug.
+	 * User specified the SSH2 DH GEX bug.
 	 */
 	ssh->remote_bugs |= BUG_SSH2_DH_GEX;
 	logevent("We believe remote version has SSH2 DH group exchange bug");
@@ -1876,11 +1889,11 @@ static int do_ssh_init(Ssh ssh, unsigned char c)
     s->proto2 = ssh_versioncmp(s->version, "1.99") >= 0;
 
     if (cfg.sshprot == 0 && !s->proto1) {
-	bombout(("SSH protocol version 1 required by user but not provided by server"));
+	bombout((ssh,"SSH protocol version 1 required by user but not provided by server"));
 	crReturn(0);
     }
     if (cfg.sshprot == 3 && !s->proto2) {
-	bombout(("SSH protocol version 2 required by user but not provided by server"));
+	bombout((ssh,"SSH protocol version 2 required by user but not provided by server"));
 	crReturn(0);
     }
 
@@ -1987,7 +2000,7 @@ 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(error_msg);
+	connection_fatal(ssh->frontend, error_msg);
     } else {
 	/* Otherwise, the remote side closed the connection normally. */
     }
@@ -1997,7 +2010,7 @@ static int ssh_closing(Plug plug, char *error_msg, int error_code,
 static int ssh_receive(Plug plug, int urgent, char *data, int len)
 {
     Ssh ssh = (Ssh) plug;
-    ssh_gotdata(ssh, data, len);
+    ssh_gotdata(ssh, (unsigned char *)data, len);
     if (ssh->state == SSH_STATE_CLOSED) {
 	if (ssh->s) {
 	    sk_close(ssh->s);
@@ -2050,27 +2063,22 @@ static char *connect_to_host(Ssh ssh, char *host, int port,
     /*
      * Try to find host.
      */
-    {
-	char buf[200];
-	sprintf(buf, "Looking up host \"%.170s\"", host);
-	logevent(buf);
-    }
-    addr = sk_namelookup(host, realhost);
-    if ((err = sk_addr_error(addr)))
+    logeventf(ssh, "Looking up host \"%s\"", host);
+    addr = name_lookup(host, port, realhost);
+    if ((err = sk_addr_error(addr)) != NULL)
 	return err;
 
     /*
      * Open socket.
      */
     {
-	char buf[200], addrbuf[100];
+	char addrbuf[100];
 	sk_getaddr(addr, addrbuf, 100);
-	sprintf(buf, "Connecting to %.100s port %d", addrbuf, port);
-	logevent(buf);
+	logeventf(ssh, "Connecting to %s port %d", addrbuf, port);
     }
     ssh->fn = &fn_table;
     ssh->s = new_connection(addr, *realhost, port, 0, 1, nodelay, (Plug) ssh);
-    if ((err = sk_socket_error(ssh->s))) {
+    if ((err = sk_socket_error(ssh->s)) != NULL) {
 	ssh->s = NULL;
 	return err;
     }
@@ -2236,7 +2244,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	crWaitUntil(ispkt);
 
     if (ssh->pktin.type != SSH1_SMSG_PUBLIC_KEY) {
-	bombout(("Public key packet not received"));
+	bombout((ssh,"Public key packet not received"));
 	crReturn(0);
     }
 
@@ -2297,7 +2305,8 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	    fatalbox("Out of memory");
 	rsastr_fmt(keystr, &hostkey);
 	rsa_fingerprint(fingerprint, sizeof(fingerprint), &hostkey);
-	verify_ssh_host_key(ssh->savedhost, ssh->savedport, "rsa", keystr,
+	verify_ssh_host_key(ssh->frontend,
+			    ssh->savedhost, ssh->savedport, "rsa", keystr,
 			    fingerprint);
 	sfree(keystr);
     }
@@ -2345,17 +2354,17 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	}
 	if (!cipher_chosen) {
 	    if ((s->supported_ciphers_mask & (1 << SSH_CIPHER_3DES)) == 0)
-		bombout(("Server violates SSH 1 protocol by not "
+		bombout((ssh,"Server violates SSH 1 protocol by not "
 			 "supporting 3DES encryption"));
 	    else
 		/* shouldn't happen */
-		bombout(("No supported ciphers found"));
+		bombout((ssh,"No supported ciphers found"));
 	    crReturn(0);
 	}
 
 	/* Warn about chosen cipher if necessary. */
 	if (warn)
-	    askcipher(cipher_string, 0);
+	    askcipher(ssh->frontend, cipher_string, 0);
     }
 
     switch (s->cipher_type) {
@@ -2386,11 +2395,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		   &ssh_3des);
     ssh->v1_cipher_ctx = ssh->cipher->make_context();
     ssh->cipher->sesskey(ssh->v1_cipher_ctx, ssh->session_key);
-    {
-	char buf[256];
-	sprintf(buf, "Initialised %.200s encryption", ssh->cipher->text_name);
-	logevent(buf);
-    }
+    logeventf(ssh, "Initialised %s encryption", ssh->cipher->text_name);
 
     ssh->crcda_ctx = crcda_make_context();
     logevent("Installing CRC compensation attack detector");
@@ -2398,7 +2403,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     crWaitUntil(ispkt);
 
     if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
-	bombout(("Encryption not successfully enabled"));
+	bombout((ssh,"Encryption not successfully enabled"));
 	crReturn(0);
     }
 
@@ -2512,7 +2517,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    s->p += ssh1_read_bignum(s->p, &s->key.modulus);
 		    s->commentlen = GET_32BIT(s->p);
 		    s->p += 4;
-		    s->commentp = s->p;
+		    s->commentp = (char *)s->p;
 		    s->p += s->commentlen;
 		    send_packet(ssh, SSH1_CMSG_AUTH_RSA,
 				PKT_BIGNUM, s->key.modulus, PKT_END);
@@ -2654,8 +2659,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	    char msgbuf[256];
 	    if (flags & FLAG_VERBOSE)
 		c_write_str(ssh, "Trying public key authentication.\r\n");
-	    sprintf(msgbuf, "Trying public key \"%.200s\"", cfg.keyfile);
-	    logevent(msgbuf);
+	    logeventf(ssh, "Trying public key \"%s\"", cfg.keyfile);
 	    type = key_type(cfg.keyfile);
 	    if (type != SSH_KEYTYPE_SSH1) {
 		sprintf(msgbuf, "Key is of wrong type (%s)",
@@ -2692,7 +2696,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			    PKT_STR, "No more passwords available to try",
 			    PKT_END);
 		logevent("Unable to authenticate");
-		connection_fatal("Unable to authenticate");
+		connection_fatal(ssh->frontend, "Unable to authenticate");
 		ssh->state = SSH_STATE_CLOSED;
 		crReturn(1);
 	    }
@@ -2748,7 +2752,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		continue;	       /* go and try password */
 	    }
 	    if (ssh->pktin.type != SSH1_SMSG_AUTH_RSA_CHALLENGE) {
-		bombout(("Bizarre response to offer of public key"));
+		bombout((ssh,"Bizarre response to offer of public key"));
 		crReturn(0);
 	    }
 
@@ -2784,7 +2788,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 				" our public key.\r\n");
 		continue;	       /* go and try password */
 	    } else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
-		bombout(("Bizarre response to RSA authentication response"));
+		bombout((ssh,"Bizarre response to RSA authentication response"));
 		crReturn(0);
 	    }
 
@@ -2917,7 +2921,7 @@ static int do_ssh1_login(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		c_write_str(ssh, "Access denied\r\n");
 	    logevent("Authentication refused");
 	} else if (ssh->pktin.type != SSH1_SMSG_SUCCESS) {
-	    bombout(("Strange packet received, type %d", ssh->pktin.type));
+	    bombout((ssh,"Strange packet received, type %d", ssh->pktin.type));
 	    crReturn(0);
 	}
     }
@@ -3017,7 +3021,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	} while (!ispkt);
 	if (ssh->pktin.type != SSH1_SMSG_SUCCESS
 	    && ssh->pktin.type != SSH1_SMSG_FAILURE) {
-	    bombout(("Protocol confusion"));
+	    bombout((ssh,"Protocol confusion"));
 	    crReturnV;
 	} else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
 	    logevent("Agent forwarding refused");
@@ -3030,11 +3034,13 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     if (cfg.x11_forward) {
 	char proto[20], data[64];
 	logevent("Requesting X11 forwarding");
-	x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
+	ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
+				       data, sizeof(data));
 	if (ssh->v1_local_protoflags & SSH1_PROTOFLAG_SCREEN_NUMBER) {
 	    send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
 			PKT_STR, proto, PKT_STR, data,
-			PKT_INT, 0, PKT_END);
+			PKT_INT, x11_get_screen_number(cfg.x11_display),
+			PKT_END);
 	} else {
 	    send_packet(ssh, SSH1_CMSG_X11_REQUEST_FORWARDING,
 			PKT_STR, proto, PKT_STR, data, PKT_END);
@@ -3044,7 +3050,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	} while (!ispkt);
 	if (ssh->pktin.type != SSH1_SMSG_SUCCESS
 	    && ssh->pktin.type != SSH1_SMSG_FAILURE) {
-	    bombout(("Protocol confusion"));
+	    bombout((ssh,"Protocol confusion"));
 	    crReturnV;
 	} else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
 	    logevent("X11 forwarding refused");
@@ -3058,91 +3064,104 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	char type;
 	int n;
 	int sport,dport,sserv,dserv;
-	char sports[256], dports[256], host[256];
-	char buf[1024];
-	struct servent *se;
+	char sports[256], dports[256], saddr[256], host[256];
 
 	ssh->rportfwds = newtree234(ssh_rportcmp_ssh1);
         /* Add port forwardings. */
 	ssh->portfwd_strptr = cfg.portfwd;
 	while (*ssh->portfwd_strptr) {
 	    type = *ssh->portfwd_strptr++;
+	    saddr[0] = '\0';
 	    n = 0;
-	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t')
-		sports[n++] = *ssh->portfwd_strptr++;
+	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
+		if (*ssh->portfwd_strptr == ':') {
+		    /*
+		     * We've seen a colon in the middle of the
+		     * source port number. This means that
+		     * everything we've seen until now is the
+		     * source _address_, so we'll move it into
+		     * saddr and start sports from the beginning
+		     * again.
+		     */
+		    ssh->portfwd_strptr++;
+		    sports[n] = '\0';
+		    strcpy(saddr, sports);
+		    n = 0;
+		}
+		if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
+	    }
 	    sports[n] = 0;
 	    if (*ssh->portfwd_strptr == '\t')
 		ssh->portfwd_strptr++;
 	    n = 0;
-	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':')
-		host[n++] = *ssh->portfwd_strptr++;
+	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
+		if (n < 255) host[n++] = *ssh->portfwd_strptr++;
+	    }
 	    host[n] = 0;
 	    if (*ssh->portfwd_strptr == ':')
 		ssh->portfwd_strptr++;
 	    n = 0;
-	    while (*ssh->portfwd_strptr)
-		dports[n++] = *ssh->portfwd_strptr++;
+	    while (*ssh->portfwd_strptr) {
+		if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
+	    }
 	    dports[n] = 0;
 	    ssh->portfwd_strptr++;
 	    dport = atoi(dports);
 	    dserv = 0;
 	    if (dport == 0) {
 		dserv = 1;
-		se = getservbyname(dports, NULL);
-		if (se != NULL) {
-		    dport = ntohs(se->s_port);
-		} else {
-		    sprintf(buf,
-			    "Service lookup failed for destination port \"%s\"",
-			    dports);
-		    logevent(buf);
+		dport = net_service_lookup(dports);
+		if (!dport) {
+		    logeventf(ssh, "Service lookup failed for"
+			      " destination port \"%s\"", dports);
 		}
 	    }
 	    sport = atoi(sports);
 	    sserv = 0;
 	    if (sport == 0) {
 		sserv = 1;
-		se = getservbyname(sports, NULL);
-		if (se != NULL) {
-		    sport = ntohs(se->s_port);
-		} else {
-		    sprintf(buf,
-			    "Service lookup failed for source port \"%s\"",
-			    sports);
-		    logevent(buf);
+		sport = net_service_lookup(sports);
+		if (!sport) {
+		    logeventf(ssh, "Service lookup failed for source"
+			      " port \"%s\"", sports);
 		}
 	    }
 	    if (sport && dport) {
 		if (type == 'L') {
-		    pfd_addforward(host, dport, sport, ssh);
-		    sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to"
-			    " %s:%.*s%.*s%d%.*s",
-			    sserv ? strlen(sports) : 0, sports,
-			    sserv, "(", sport, sserv, ")",
-			    host,
-			    dserv ? strlen(dports) : 0, dports,
-			    dserv, "(", dport, dserv, ")");
-		    logevent(buf);
+		    pfd_addforward(host, dport, *saddr ? saddr : NULL,
+				   sport, ssh);
+		    logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
+			      " forwarding to %s:%.*s%.*s%d%.*s",
+			      (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
+			      (int)(*saddr?1:0), ":",
+			      (int)(sserv ? strlen(sports) : 0), sports,
+			      sserv, "(", sport, sserv, ")",
+			      host,
+			      (int)(dserv ? strlen(dports) : 0), dports,
+			      dserv, "(", dport, dserv, ")");
 		} else {
 		    struct ssh_rportfwd *pf;
 		    pf = smalloc(sizeof(*pf));
 		    strcpy(pf->dhost, host);
 		    pf->dport = dport;
+		    if (saddr) {
+			logeventf(ssh,
+				  "SSH1 cannot handle source address spec \"%s:%d\"; ignoring",
+				  saddr, sport);
+		    }
 		    if (add234(ssh->rportfwds, pf) != pf) {
-			sprintf(buf, 
-				"Duplicate remote port forwarding to %s:%d",
-				host, dport);
-			logevent(buf);
+			logeventf(ssh, 
+				  "Duplicate remote port forwarding to %s:%d",
+				  host, dport);
 			sfree(pf);
 		    } else {
-			sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s"
-				" forward to %s:%.*s%.*s%d%.*s",
-			    sserv ? strlen(sports) : 0, sports,
-			    sserv, "(", sport, sserv, ")",
-			    host,
-			    dserv ? strlen(dports) : 0, dports,
-			    dserv, "(", dport, dserv, ")");
-			logevent(buf);
+			logeventf(ssh, "Requesting remote port %.*s%.*s%d%.*s"
+				  " forward to %s:%.*s%.*s%d%.*s",
+				  (int)(sserv ? strlen(sports) : 0), sports,
+				  sserv, "(", sport, sserv, ")",
+				  host,
+				  (int)(dserv ? strlen(dports) : 0), dports,
+				  dserv, "(", dport, dserv, ")");
 			send_packet(ssh, SSH1_CMSG_PORT_FORWARD_REQUEST,
 				    PKT_INT, sport,
 				    PKT_STR, host,
@@ -3153,7 +3172,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			} while (!ispkt);
 			if (ssh->pktin.type != SSH1_SMSG_SUCCESS
 			    && ssh->pktin.type != SSH1_SMSG_FAILURE) {
-			    bombout(("Protocol confusion"));
+			    bombout((ssh,"Protocol confusion"));
 			    crReturnV;
 			} else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
 			    c_write_str(ssh, "Server refused port"
@@ -3178,7 +3197,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	} while (!ispkt);
 	if (ssh->pktin.type != SSH1_SMSG_SUCCESS
 	    && ssh->pktin.type != SSH1_SMSG_FAILURE) {
-	    bombout(("Protocol confusion"));
+	    bombout((ssh,"Protocol confusion"));
 	    crReturnV;
 	} else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
 	    c_write_str(ssh, "Server refused to allocate pty\r\n");
@@ -3196,7 +3215,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	} while (!ispkt);
 	if (ssh->pktin.type != SSH1_SMSG_SUCCESS
 	    && ssh->pktin.type != SSH1_SMSG_FAILURE) {
-	    bombout(("Protocol confusion"));
+	    bombout((ssh,"Protocol confusion"));
 	    crReturnV;
 	} else if (ssh->pktin.type == SSH1_SMSG_FAILURE) {
 	    c_write_str(ssh, "Server refused to compress\r\n");
@@ -3249,7 +3268,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		int bufsize =
 		    from_backend(ssh->frontend,
 				 ssh->pktin.type == SSH1_SMSG_STDERR_DATA,
-				 ssh->pktin.body + 4, len);
+				 (char *)(ssh->pktin.body) + 4, len);
 		if (!ssh->v1_stdout_throttling && bufsize > SSH1_BUFFER_LIMIT) {
 		    ssh->v1_stdout_throttling = 1;
 		    ssh1_throttle(ssh, +1);
@@ -3273,7 +3292,8 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    c = smalloc(sizeof(struct ssh_channel));
 		    c->ssh = ssh;
 
-		    if (x11_init(&c->u.x11.s, cfg.x11_display, c) != NULL) {
+		    if (x11_init(&c->u.x11.s, cfg.x11_display, c,
+				 ssh->x11auth) != NULL) {
 			logevent("opening X11 forward connection failed");
 			sfree(c);
 			send_packet(ssh, SSH1_MSG_CHANNEL_OPEN_FAILURE,
@@ -3329,7 +3349,8 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		c->ssh = ssh;
 
 		hostsize = GET_32BIT(ssh->pktin.body+4);
-		for(h = host, p = ssh->pktin.body+8; hostsize != 0; hostsize--) {
+		for (h = host, p = (char *)(ssh->pktin.body+8);
+		     hostsize != 0; hostsize--) {
 		    if (h+1 < host+sizeof(host))
 			*h++ = *p;
 		    p++;
@@ -3399,7 +3420,6 @@ 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 localid = GET_32BIT(ssh->pktin.body+4);
 		struct ssh_channel *c;
 
 		c = find234(ssh->channels, &remoteid, ssh_channelfind);
@@ -3446,7 +3466,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			sfree(c);
 		    }
 		} else {
-		    bombout(("Received CHANNEL_CLOSE%s for %s channel %d\n",
+		    bombout((ssh,"Received CHANNEL_CLOSE%s for %s channel %d\n",
 			     ssh->pktin.type == SSH1_MSG_CHANNEL_CLOSE ? "" :
 			     "_CONFIRMATION", c ? "half-open" : "nonexistent",
 			     i));
@@ -3462,10 +3482,10 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    int bufsize;
 		    switch (c->type) {
 		      case CHAN_X11:
-			bufsize = x11_send(c->u.x11.s, p, len);
+			bufsize = x11_send(c->u.x11.s, (char *)p, len);
 			break;
 		      case CHAN_SOCKDATA:
-			bufsize = pfd_send(c->u.pfd.s, p, len);
+			bufsize = pfd_send(c->u.pfd.s, (char *)p, len);
 			break;
 		      case CHAN_AGENT:
 			/* Data for an agent message. Buffer it. */
@@ -3548,7 +3568,7 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
                 ssh->state = SSH_STATE_CLOSED;
                 crReturnV;
 	    } else {
-		bombout(("Strange packet received: type %d", ssh->pktin.type));
+		bombout((ssh,"Strange packet received: type %d", ssh->pktin.type));
 		crReturnV;
 	    }
 	} else {
@@ -3570,7 +3590,10 @@ static void ssh1_protocol(Ssh ssh, unsigned char *in, int inlen, int ispkt)
  */
 static int in_commasep_string(char *needle, char *haystack, int haylen)
 {
-    int needlen = strlen(needle);
+    int needlen;
+    if (!needle || !haystack)	       /* protect against null pointers */
+	return 0;
+    needlen = strlen(needle);
     while (1) {
 	/*
 	 * Is it at the start of the string?
@@ -3596,8 +3619,9 @@ static int in_commasep_string(char *needle, char *haystack, int haylen)
 /*
  * SSH2 key creation method.
  */
-static void ssh2_mkkey(Ssh ssh, Bignum K, char *H, char *sessid, char chr,
-		       char *keyspace)
+static void ssh2_mkkey(Ssh ssh, Bignum K, unsigned char *H,
+		       unsigned char *sessid, char chr,
+		       unsigned char *keyspace)
 {
     SHA_State s;
     /* First 20 bytes. */
@@ -3805,7 +3829,8 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
     if (!ispkt)
 	crWaitUntil(ispkt);
-    sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
+    if (ssh->pktin.length > 5)
+	sha_string(&ssh->exhash, ssh->pktin.data + 5, ssh->pktin.length - 5);
 
     /*
      * Now examine the other side's KEXINIT to see what we're up
@@ -3816,7 +3841,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	int i, j, len;
 
 	if (ssh->pktin.type != SSH2_MSG_KEXINIT) {
-	    bombout(("expected key exchange packet from server"));
+	    bombout((ssh,"expected key exchange packet from server"));
 	    crReturn(0);
 	}
 	ssh->kex = NULL;
@@ -3861,12 +3886,13 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	    }
 	    if (s->cscipher_tobe) {
 		if (s->warn)
-		    askcipher(s->cscipher_tobe->name, 1);
+		    askcipher(ssh->frontend, s->cscipher_tobe->name, 1);
 		break;
 	    }
 	}
 	if (!s->cscipher_tobe) {
-	    bombout(("Couldn't agree a client-to-server cipher (available: %s)", str));
+	    bombout((ssh,"Couldn't agree a client-to-server cipher (available: %s)",
+		     str ? str : "(null)"));
 	    crReturn(0);
 	}
 
@@ -3886,12 +3912,13 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	    }
 	    if (s->sccipher_tobe) {
 		if (s->warn)
-		    askcipher(s->sccipher_tobe->name, 2);
+		    askcipher(ssh->frontend, s->sccipher_tobe->name, 2);
 		break;
 	    }
 	}
 	if (!s->sccipher_tobe) {
-	    bombout(("Couldn't agree a server-to-client cipher (available: %s)", str));
+	    bombout((ssh,"Couldn't agree a server-to-client cipher (available: %s)",
+		     str ? str : "(null)"));
 	    crReturn(0);
 	}
 
@@ -3964,7 +3991,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
 	crWaitUntil(ispkt);
 	if (ssh->pktin.type != SSH2_MSG_KEX_DH_GEX_GROUP) {
-	    bombout(("expected key exchange group packet from server"));
+	    bombout((ssh,"expected key exchange group packet from server"));
 	    crReturn(0);
 	}
 	s->p = ssh2_pkt_getmp(ssh);
@@ -3990,7 +4017,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
     crWaitUntil(ispkt);
     if (ssh->pktin.type != s->kex_reply_value) {
-	bombout(("expected key exchange reply packet from server"));
+	bombout((ssh,"expected key exchange reply packet from server"));
 	crReturn(0);
     }
     ssh2_pkt_getstring(ssh, &s->hostkeydata, &s->hostkeylen);
@@ -4020,8 +4047,8 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     s->hkey = ssh->hostkey->newkey(s->hostkeydata, s->hostkeylen);
     if (!s->hkey ||
 	!ssh->hostkey->verifysig(s->hkey, s->sigdata, s->siglen,
-				 s->exchange_hash, 20)) {
-	bombout(("Server's host key did not match the signature supplied"));
+				 (char *)s->exchange_hash, 20)) {
+	bombout((ssh,"Server's host key did not match the signature supplied"));
 	crReturn(0);
     }
 
@@ -4031,7 +4058,8 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
      */
     s->keystr = ssh->hostkey->fmtkey(s->hkey);
     s->fingerprint = ssh->hostkey->fingerprint(s->hkey);
-    verify_ssh_host_key(ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
+    verify_ssh_host_key(ssh->frontend,
+			ssh->savedhost, ssh->savedport, ssh->hostkey->keytype,
 			s->keystr, s->fingerprint);
     if (s->first_kex) {		       /* don't bother logging this in rekeys */
 	logevent("Host key fingerprint is:");
@@ -4052,7 +4080,7 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
      */
     crWaitUntil(ispkt);
     if (ssh->pktin.type != SSH2_MSG_NEWKEYS) {
-	bombout(("expected new-keys packet from server"));
+	bombout((ssh,"expected new-keys packet from server"));
 	crReturn(0);
     }
 
@@ -4111,26 +4139,16 @@ static int do_ssh2_transport(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	ssh2_mkkey(ssh,s->K,s->exchange_hash,ssh->v2_session_id,'F',keyspace);
 	ssh->scmac->setkey(ssh->sc_mac_ctx, keyspace);
     }
-    {
-	char buf[256];
-	sprintf(buf, "Initialised %.200s client->server encryption",
-		ssh->cscipher->text_name);
-	logevent(buf);
-	sprintf(buf, "Initialised %.200s server->client encryption",
-		ssh->sccipher->text_name);
-	logevent(buf);
-	if (ssh->cscomp->text_name) {
-	    sprintf(buf, "Initialised %.200s compression",
-		    ssh->cscomp->text_name);
-	    logevent(buf);
-	}
-	if (ssh->sccomp->text_name) {
-	    sprintf(buf, "Initialised %.200s decompression",
-		    ssh->sccomp->text_name);
-	    logevent(buf);
-	}
-    }
-
+    logeventf(ssh, "Initialised %.200s client->server encryption",
+	      ssh->cscipher->text_name);
+    logeventf(ssh, "Initialised %.200s server->client encryption",
+	      ssh->sccipher->text_name);
+    if (ssh->cscomp->text_name)
+	logeventf(ssh, "Initialised %s compression",
+		  ssh->cscomp->text_name);
+    if (ssh->sccomp->text_name)
+	logeventf(ssh, "Initialised %s decompression",
+		  ssh->sccomp->text_name);
 
     /*
      * If this is the first key exchange phase, we must pass the
@@ -4277,7 +4295,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     ssh2_pkt_send(ssh);
     crWaitUntilV(ispkt);
     if (ssh->pktin.type != SSH2_MSG_SERVICE_ACCEPT) {
-	bombout(("Server refused user authentication protocol"));
+	bombout((ssh,"Server refused user authentication protocol"));
 	crReturnV;
     }
 
@@ -4340,16 +4358,17 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		} while (ret == 0);
 		if (ret < 0)
 		    cleanup_exit(0);
+		c_write_str(ssh, "\r\n");
 	    }
-	    c_write_str(ssh, "\r\n");
 	    s->username[strcspn(s->username, "\n\r")] = '\0';
 	} else {
-	    char stuff[200];
+	    char *stuff;
 	    strncpy(s->username, cfg.username, sizeof(s->username));
 	    s->username[sizeof(s->username)-1] = '\0';
 	    if ((flags & FLAG_VERBOSE) || (flags & FLAG_INTERACTIVE)) {
-		sprintf(stuff, "Using username \"%s\".\r\n", s->username);
+		stuff = dupprintf("Using username \"%s\".\r\n", s->username);
 		c_write_str(ssh, stuff);
+		sfree(stuff);
 	    }
 	}
 	s->got_username = TRUE;
@@ -4377,19 +4396,21 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	/* Load the pub half of cfg.keyfile so we notice if it's in Pageant */
 	if (*cfg.keyfile) {
 	    int keytype;
-	    logeventf("Reading private key file \"%.150s\"", cfg.keyfile);
+	    logeventf(ssh, "Reading private key file \"%.150s\"", cfg.keyfile);
 	    keytype = key_type(cfg.keyfile);
 	    if (keytype == SSH_KEYTYPE_SSH2) {
 		s->publickey_blob =
 		    ssh2_userkey_loadpub(cfg.keyfile, NULL,
 					 &s->publickey_bloblen);
 	    } else {
-		char msgbuf[256];
-		logeventf("Unable to use this key file (%s)",
-			key_type_to_str(keytype));
-		sprintf(msgbuf, "Unable to use key file \"%.150s\" (%s)\r\n",
-			cfg.keyfile, key_type_to_str(keytype));
+		char *msgbuf;
+		logeventf(ssh, "Unable to use this key file (%s)",
+			  key_type_to_str(keytype));
+		msgbuf = dupprintf("Unable to use key file \"%.150s\""
+				   " (%s)\r\n", cfg.keyfile,
+				   key_type_to_str(keytype));
 		c_write_str(ssh, msgbuf);
+		sfree(msgbuf);
 		s->publickey_blob = NULL;
 	    }
 	} else
@@ -4437,7 +4458,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		if (!s->gotit)
 		    s->curr_prompt = 0;
 	    } else if (ssh->pktin.type != SSH2_MSG_USERAUTH_FAILURE) {
-		bombout(("Strange packet received during authentication: type %d",
+		bombout((ssh,"Strange packet received during authentication: type %d",
 			 ssh->pktin.type));
 		crReturnV;
 	    }
@@ -4564,13 +4585,13 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			    logevent("This key matches configured key file");
 			    s->tried_pubkey_config = 1;
 			}
-			s->pkblob = s->p;
+			s->pkblob = (char *)s->p;
 			s->p += s->pklen;
 			s->alglen = GET_32BIT(s->pkblob);
 			s->alg = s->pkblob + 4;
 			s->commentlen = GET_32BIT(s->p);
 			s->p += 4;
-			s->commentp = s->p;
+			s->commentp = (char *)s->p;
 			s->p += s->commentlen;
 			ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
 			ssh2_pkt_addstring(ssh, s->username);
@@ -4676,8 +4697,10 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		 * First, offer the public blob to see if the server is
 		 * willing to accept it.
 		 */
-		pub_blob = ssh2_userkey_loadpub(cfg.keyfile, &algorithm,
-						&pub_blob_len);
+		pub_blob =
+		    (unsigned char *)ssh2_userkey_loadpub(cfg.keyfile,
+							  &algorithm,
+							  &pub_blob_len);
 		if (pub_blob) {
 		    ssh2_pkt_init(ssh, SSH2_MSG_USERAUTH_REQUEST);
 		    ssh2_pkt_addstring(ssh, s->username);
@@ -4686,7 +4709,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    ssh2_pkt_addbool(ssh, FALSE);	/* no signature included */
 		    ssh2_pkt_addstring(ssh, algorithm);
 		    ssh2_pkt_addstring_start(ssh);
-		    ssh2_pkt_addstring_data(ssh, pub_blob, pub_blob_len);
+		    ssh2_pkt_addstring_data(ssh, (char *)pub_blob,
+					    pub_blob_len);
 		    ssh2_pkt_send(ssh);
 		    logevent("Offered public key");	/* FIXME */
 
@@ -4826,7 +4850,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 			ssh2_pkt_addstring(ssh, "en");	/* language tag */
 			ssh2_pkt_send(ssh);
 			logevent("Unable to authenticate");
-			connection_fatal("Unable to authenticate");
+			connection_fatal(ssh->frontend,
+					 "Unable to authenticate");
 			ssh->state = SSH_STATE_CLOSED;
 			crReturnV;
 		    }
@@ -4886,7 +4911,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    ssh2_pkt_addstring(ssh, key->alg->name);
 		    pkblob = key->alg->public_blob(key->data, &pkblob_len);
 		    ssh2_pkt_addstring_start(ssh);
-		    ssh2_pkt_addstring_data(ssh, pkblob, pkblob_len);
+		    ssh2_pkt_addstring_data(ssh, (char *)pkblob, pkblob_len);
 
 		    /*
 		     * The data to be signed is:
@@ -4902,7 +4927,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    memcpy(sigdata + 4, ssh->v2_session_id, 20);
 		    memcpy(sigdata + 24, ssh->pktout.data + 5,
 			   ssh->pktout.length - 5);
-		    sigblob = key->alg->sign(key->data, sigdata,
+		    sigblob = key->alg->sign(key->data, (char *)sigdata,
 					     sigdata_len, &sigblob_len);
 		    ssh2_add_sigblob(ssh, pkblob, pkblob_len,
 				     sigblob, sigblob_len);
@@ -5034,12 +5059,12 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     ssh2_pkt_send(ssh);
     crWaitUntilV(ispkt);
     if (ssh->pktin.type != SSH2_MSG_CHANNEL_OPEN_CONFIRMATION) {
-	bombout(("Server refused to open a session"));
+	bombout((ssh,"Server refused to open a session"));
 	crReturnV;
 	/* FIXME: error data comes back in FAILURE packet */
     }
     if (ssh2_pkt_getuint32(ssh) != ssh->mainchan->localid) {
-	bombout(("Server's channel confirmation cited wrong channel"));
+	bombout((ssh,"Server's channel confirmation cited wrong channel"));
 	crReturnV;
     }
     ssh->mainchan->remoteid = ssh2_pkt_getuint32(ssh);
@@ -5057,7 +5082,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
     if (cfg.x11_forward) {
 	char proto[20], data[64];
 	logevent("Requesting X11 forwarding");
-	x11_invent_auth(proto, sizeof(proto), data, sizeof(data));
+	ssh->x11auth = x11_invent_auth(proto, sizeof(proto),
+				       data, sizeof(data));
 	ssh2_pkt_init(ssh, SSH2_MSG_CHANNEL_REQUEST);
 	ssh2_pkt_adduint32(ssh, ssh->mainchan->remoteid);
 	ssh2_pkt_addstring(ssh, "x11-req");
@@ -5065,7 +5091,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	ssh2_pkt_addbool(ssh, 0);	       /* many connections */
 	ssh2_pkt_addstring(ssh, proto);
 	ssh2_pkt_addstring(ssh, data);
-	ssh2_pkt_adduint32(ssh, 0);	       /* screen number */
+	ssh2_pkt_adduint32(ssh, x11_get_screen_number(cfg.x11_display));
 	ssh2_pkt_send(ssh);
 
 	do {
@@ -5082,7 +5108,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
 	if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
 	    if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
-		bombout(("Unexpected response to X11 forwarding request:"
+		bombout((ssh,"Unexpected response to X11 forwarding request:"
 			 " packet type %d", ssh->pktin.type));
 		crReturnV;
 	    }
@@ -5100,71 +5126,81 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	char type;
 	int n;
 	int sport,dport,sserv,dserv;
-	char sports[256], dports[256], host[256];
-	char buf[1024];
-	struct servent *se;
+	char sports[256], dports[256], saddr[256], host[256];
 
 	ssh->rportfwds = newtree234(ssh_rportcmp_ssh2);
         /* Add port forwardings. */
 	ssh->portfwd_strptr = cfg.portfwd;
 	while (*ssh->portfwd_strptr) {
 	    type = *ssh->portfwd_strptr++;
+	    saddr[0] = '\0';
 	    n = 0;
-	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t')
-		sports[n++] = *ssh->portfwd_strptr++;
+	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != '\t') {
+		if (*ssh->portfwd_strptr == ':') {
+		    /*
+		     * We've seen a colon in the middle of the
+		     * source port number. This means that
+		     * everything we've seen until now is the
+		     * source _address_, so we'll move it into
+		     * saddr and start sports from the beginning
+		     * again.
+		     */
+		    ssh->portfwd_strptr++;
+		    sports[n] = '\0';
+		    strcpy(saddr, sports);
+		    n = 0;
+		}
+		if (n < 255) sports[n++] = *ssh->portfwd_strptr++;
+	    }
 	    sports[n] = 0;
 	    if (*ssh->portfwd_strptr == '\t')
 		ssh->portfwd_strptr++;
 	    n = 0;
-	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':')
-		host[n++] = *ssh->portfwd_strptr++;
+	    while (*ssh->portfwd_strptr && *ssh->portfwd_strptr != ':') {
+		if (n < 255) host[n++] = *ssh->portfwd_strptr++;
+	    }
 	    host[n] = 0;
 	    if (*ssh->portfwd_strptr == ':')
 		ssh->portfwd_strptr++;
 	    n = 0;
-	    while (*ssh->portfwd_strptr)
-		dports[n++] = *ssh->portfwd_strptr++;
+	    while (*ssh->portfwd_strptr) {
+		if (n < 255) dports[n++] = *ssh->portfwd_strptr++;
+	    }
 	    dports[n] = 0;
 	    ssh->portfwd_strptr++;
 	    dport = atoi(dports);
 	    dserv = 0;
 	    if (dport == 0) {
 		dserv = 1;
-		se = getservbyname(dports, NULL);
-		if (se != NULL) {
-		    dport = ntohs(se->s_port);
-		} else {
-		    sprintf(buf,
-			    "Service lookup failed for destination port \"%s\"",
-			    dports);
-		    logevent(buf);
+		dport = net_service_lookup(dports);
+		if (!dport) {
+		    logeventf(ssh, "Service lookup failed for destination"
+			      " port \"%s\"", dports);
 		}
 	    }
 	    sport = atoi(sports);
 	    sserv = 0;
 	    if (sport == 0) {
 		sserv = 1;
-		se = getservbyname(sports, NULL);
-		if (se != NULL) {
-		    sport = ntohs(se->s_port);
-		} else {
-		    sprintf(buf,
-			    "Service lookup failed for source port \"%s\"",
-			    sports);
-		    logevent(buf);
+		sport = net_service_lookup(sports);
+		if (!sport) {
+		    logeventf(ssh, "Service lookup failed for source"
+			      " port \"%s\"", sports);
 		}
 	    }
 	    if (sport && dport) {
 		if (type == 'L') {
-		    pfd_addforward(host, dport, sport, ssh);
-		    sprintf(buf, "Local port %.*s%.*s%d%.*s forwarding to"
-			    " %s:%.*s%.*s%d%.*s",
-			    sserv ? strlen(sports) : 0, sports,
-			    sserv, "(", sport, sserv, ")",
-			    host,
-			    dserv ? strlen(dports) : 0, dports,
-			    dserv, "(", dport, dserv, ")");
-		    logevent(buf);
+		    pfd_addforward(host, dport, *saddr ? saddr : NULL,
+				   sport, ssh);
+		    logeventf(ssh, "Local port %.*s%.*s%.*s%.*s%d%.*s"
+			      " forwarding to %s:%.*s%.*s%d%.*s",
+			      (int)(*saddr?strlen(saddr):0), *saddr?saddr:NULL,
+			      (int)(*saddr?1:0), ":",
+			      (int)(sserv ? strlen(sports) : 0), sports,
+			      sserv, "(", sport, sserv, ")",
+			      host,
+			      (int)(dserv ? strlen(dports) : 0), dports,
+			      dserv, "(", dport, dserv, ")");
 		} else {
 		    struct ssh_rportfwd *pf;
 		    pf = smalloc(sizeof(*pf));
@@ -5172,23 +5208,26 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    pf->dport = dport;
 		    pf->sport = sport;
 		    if (add234(ssh->rportfwds, pf) != pf) {
-			sprintf(buf, 
-				"Duplicate remote port forwarding to %s:%d",
-				host, dport);
-			logevent(buf);
+			logeventf(ssh, "Duplicate remote port forwarding"
+				  " to %s:%d", host, dport);
 			sfree(pf);
 		    } else {
-			sprintf(buf, "Requesting remote port %.*s%.*s%d%.*s"
-				" forward to %s:%.*s%.*s%d%.*s",
-			    sserv ? strlen(sports) : 0, sports,
-			    sserv, "(", sport, sserv, ")",
-			    host,
-			    dserv ? strlen(dports) : 0, dports,
-			    dserv, "(", dport, dserv, ")");
-			logevent(buf);
+			logeventf(ssh, "Requesting remote port "
+				  "%.*s%.*s%.*s%.*s%d%.*s"
+				  " forward to %s:%.*s%.*s%d%.*s",
+				  (int)(*saddr?strlen(saddr):0),
+				  *saddr?saddr:NULL,
+				  (int)(*saddr?1:0), ":",
+				  (int)(sserv ? strlen(sports) : 0), sports,
+				  sserv, "(", sport, sserv, ")",
+				  host,
+				  (int)(dserv ? strlen(dports) : 0), dports,
+				  dserv, "(", dport, dserv, ")");
 			ssh2_pkt_init(ssh, SSH2_MSG_GLOBAL_REQUEST);
 			ssh2_pkt_addstring(ssh, "tcpip-forward");
 			ssh2_pkt_addbool(ssh, 1);/* want reply */
+			if (*saddr)
+			    ssh2_pkt_addstring(ssh, saddr);
 			if (cfg.rport_acceptall)
 			    ssh2_pkt_addstring(ssh, "0.0.0.0");
 			else
@@ -5210,7 +5249,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
 			if (ssh->pktin.type != SSH2_MSG_REQUEST_SUCCESS) {
 			    if (ssh->pktin.type != SSH2_MSG_REQUEST_FAILURE) {
-				bombout(("Unexpected response to port "
+				bombout((ssh,"Unexpected response to port "
 					 "forwarding request: packet type %d",
 					 ssh->pktin.type));
 				crReturnV;
@@ -5250,7 +5289,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
 	if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
 	    if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
-		bombout(("Unexpected response to agent forwarding request:"
+		bombout((ssh,"Unexpected response to agent forwarding request:"
 			 " packet type %d", ssh->pktin.type));
 		crReturnV;
 	    }
@@ -5293,7 +5332,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
 	if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
 	    if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
-		bombout(("Unexpected response to pty request:"
+		bombout((ssh,"Unexpected response to pty request:"
 			 " packet type %d", ssh->pktin.type));
 		crReturnV;
 	    }
@@ -5351,7 +5390,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 	} while (ssh->pktin.type == SSH2_MSG_CHANNEL_WINDOW_ADJUST);
 	if (ssh->pktin.type != SSH2_MSG_CHANNEL_SUCCESS) {
 	    if (ssh->pktin.type != SSH2_MSG_CHANNEL_FAILURE) {
-		bombout(("Unexpected response to shell/command request:"
+		bombout((ssh,"Unexpected response to shell/command request:"
 			 " packet type %d", ssh->pktin.type));
 		crReturnV;
 	    }
@@ -5366,7 +5405,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		ssh->fallback_cmd = TRUE;
 		continue;
 	    }
-	    bombout(("Server refused to start a shell/command"));
+	    bombout((ssh,"Server refused to start a shell/command"));
 	    crReturnV;
 	} else {
 	    logevent("Started a shell/command");
@@ -5503,7 +5542,7 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 
 		c = find234(ssh->channels, &i, ssh_channelfind);
 		if (!c || ((int)c->remoteid) == -1) {
-		    bombout(("Received CHANNEL_CLOSE for %s channel %d\n",
+		    bombout((ssh,"Received CHANNEL_CLOSE for %s channel %d\n",
 			     c ? "half-open" : "nonexistent", i));
 		}
 		/* Do pre-close processing on the channel. */
@@ -5703,8 +5742,8 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		if (typelen == 3 && !memcmp(type, "x11", 3)) {
 		    if (!ssh->X11_fwd_enabled)
 			error = "X11 forwarding is not enabled";
-		    else if (x11_init(&c->u.x11.s, cfg.x11_display, c) !=
-			     NULL) {
+		    else if (x11_init(&c->u.x11.s, cfg.x11_display, c,
+				      ssh->x11auth) != NULL) {
 			error = "Unable to open an X11 connection";
 		    } else {
 			c->type = CHAN_X11;
@@ -5722,13 +5761,10 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    } else {
 			char *e = pfd_newconnect(&c->u.pfd.s, realpf->dhost,
 						 realpf->dport, c);
-			char buf[1024];
-			sprintf(buf, "Received remote port open request for %s:%d",
-				realpf->dhost, realpf->dport);
-			logevent(buf);
+			logeventf(ssh, "Received remote port open request"
+				  " for %s:%d", realpf->dhost, realpf->dport);
 			if (e != NULL) {
-			    sprintf(buf, "Port open failed: %s", e);
-			    logevent(buf);
+			    logeventf(ssh, "Port open failed: %s", e);
 			    error = "Port open failed";
 			} else {
 			    logevent("Forwarded port opened successfully");
@@ -5772,14 +5808,14 @@ static void do_ssh2_authconn(Ssh ssh, unsigned char *in, int inlen, int ispkt)
 		    ssh2_pkt_send(ssh);
 		}
 	    } else {
-		bombout(("Strange packet received: type %d", ssh->pktin.type));
+		bombout((ssh,"Strange packet received: type %d", ssh->pktin.type));
 		crReturnV;
 	    }
 	} else {
 	    /*
 	     * We have spare data. Add it to the channel buffer.
 	     */
-	    ssh2_add_channel_data(ssh->mainchan, in, inlen);
+	    ssh2_add_channel_data(ssh->mainchan, (char *)in, inlen);
 	    s->try_send = TRUE;
 	}
 	if (s->try_send) {
@@ -5846,7 +5882,7 @@ static char *ssh_init(void *frontend_handle, void **backend_handle,
     ssh->sccipher = NULL;
     ssh->sc_cipher_ctx = NULL;
     ssh->csmac = NULL;
-    ssh->sc_mac_ctx = NULL;
+    ssh->cs_mac_ctx = NULL;
     ssh->scmac = NULL;
     ssh->sc_mac_ctx = NULL;
     ssh->cscomp = NULL;
@@ -5860,6 +5896,7 @@ static char *ssh_init(void *frontend_handle, void **backend_handle,
     ssh->size_needed = FALSE;
     ssh->eof_needed = FALSE;
     ssh->ldisc = NULL;
+    ssh->logctx = NULL;
     {
 	static const struct Packet empty = { 0, 0, NULL, NULL, 0 };
 	ssh->pktin = ssh->pktout = empty;
@@ -5869,6 +5906,8 @@ static char *ssh_init(void *frontend_handle, void **backend_handle,
     ssh->deferred_size = 0;
     ssh->fallback_cmd = 0;
     ssh->pkt_ctx = 0;
+    ssh->x11auth = NULL;
+    ssh->v1_compressing = FALSE;
     ssh->v2_outgoing_sequence = 0;
     ssh->ssh1_rdpkt_crstate = 0;
     ssh->ssh2_rdpkt_crstate = 0;
@@ -5882,6 +5921,9 @@ static char *ssh_init(void *frontend_handle, void **backend_handle,
     ssh->do_ssh1_login_state = NULL;
     ssh->do_ssh2_transport_state = NULL;
     ssh->do_ssh2_authconn_state = NULL;
+    ssh->mainchan = NULL;
+    ssh->throttled_all = 0;
+    ssh->v1_stdout_throttling = 0;
 
     *backend_handle = ssh;
 
@@ -5918,7 +5960,7 @@ static int ssh_send(void *handle, char *buf, int len)
     if (ssh == NULL || ssh->s == NULL || ssh->protocol == NULL)
 	return 0;
 
-    ssh->protocol(ssh, buf, len, 0);
+    ssh->protocol(ssh, (unsigned char *)buf, len, 0);
 
     return ssh_sendbuffer(ssh);
 }
@@ -5975,8 +6017,6 @@ static void ssh_size(void *handle, int width, int height)
 	break;
       case SSH_STATE_SESSION:
 	if (!cfg.nopty) {
-	    if (!term)
-		return;
 	    if (ssh->version == 1) {
 		send_packet(ssh, SSH1_CMSG_WINDOW_SIZE,
 			    PKT_INT, ssh->term_height,
@@ -6082,10 +6122,8 @@ void ssh_send_port_open(void *channel, char *hostname, int port, char *org)
 {
     struct ssh_channel *c = (struct ssh_channel *)channel;
     Ssh ssh = c->ssh;
-    char buf[1024];
 
-    sprintf(buf, "Opening forwarded connection to %.512s:%d", hostname, port);
-    logevent(buf);
+    logeventf(ssh, "Opening forwarded connection to %s:%d", hostname, port);
 
     if (ssh->version == 1) {
 	send_packet(ssh, SSH1_MSG_PORT_OPEN,
@@ -6144,6 +6182,12 @@ static void ssh_provide_ldisc(void *handle, void *ldisc)
     ssh->ldisc = ldisc;
 }
 
+static void ssh_provide_logctx(void *handle, void *logctx)
+{
+    Ssh ssh = (Ssh) handle;
+    ssh->logctx = logctx;
+}
+
 static int ssh_return_exitcode(void *handle)
 {
     Ssh ssh = (Ssh) handle;
@@ -6172,6 +6216,7 @@ Backend ssh_backend = {
     ssh_sendok,
     ssh_ldisc,
     ssh_provide_ldisc,
+    ssh_provide_logctx,
     ssh_unthrottle,
     22
 };