--- old/usr/src/cmd/ssh/libssh/common/channels.c	Tue Aug 16 19:27:13 2016
+++ /dev/null	Tue Aug 16 19:26:53 2016
@@ -1,3035 +0,0 @@
-/*
- * Author: Tatu Ylonen <ylo@cs.hut.fi>
- * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
- *                    All rights reserved
- * This file contains functions for generic socket connection forwarding.
- * There is also code for initiating connection forwarding for X11 connections,
- * arbitrary tcp/ip connections, and the authentication agent connection.
- *
- * As far as I am concerned, the code I have written for this software
- * can be used freely for any purpose.  Any derived versions of this
- * software must be clearly marked as such, and if the derived work is
- * incompatible with the protocol description in the RFC file, it must be
- * called by a name other than "ssh" or "Secure Shell".
- *
- * SSH2 support added by Markus Friedl.
- * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl.  All rights reserved.
- * Copyright (c) 1999 Dug Song.  All rights reserved.
- * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- * 1. Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-/*
- * Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
- */
-
-#include "includes.h"
-RCSID("$OpenBSD: channels.c,v 1.183 2002/09/17 07:47:02 itojun Exp $");
-
-#include "ssh.h"
-#include "ssh1.h"
-#include "ssh2.h"
-#include "packet.h"
-#include "xmalloc.h"
-#include "log.h"
-#include "misc.h"
-#include "channels.h"
-#include "compat.h"
-#include "canohost.h"
-#include "key.h"
-#include "authfd.h"
-#include "pathnames.h"
-#include "bufaux.h"
-
-
-/* -- channel core */
-
-/*
- * Pointer to an array containing all allocated channels.  The array is
- * dynamically extended as needed.
- */
-static Channel **channels = NULL;
-
-/*
- * Size of the channel array.  All slots of the array must always be
- * initialized (at least the type field); unused slots set to NULL
- */
-static int channels_alloc = 0;
-
-/*
- * Maximum file descriptor value used in any of the channels.  This is
- * updated in channel_new.
- */
-static int channel_max_fd = 0;
-
-
-/* -- tcp forwarding */
-
-/*
- * Data structure for storing which hosts are permitted for forward requests.
- * The local sides of any remote forwards are stored in this array to prevent
- * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
- * network (which might be behind a firewall).
- */
-typedef struct {
-	char *host_to_connect;		/* Connect to 'host'. */
-	u_short port_to_connect;	/* Connect to 'port'. */
-	u_short listen_port;		/* Remote side should listen port number. */
-} ForwardPermission;
-
-/* List of all permitted host/port pairs to connect. */
-static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
-
-/* Number of permitted host/port pairs in the array. */
-static int num_permitted_opens = 0;
-/*
- * If this is true, all opens are permitted.  This is the case on the server
- * on which we have to trust the client anyway, and the user could do
- * anything after logging in anyway.
- */
-static int all_opens_permitted = 0;
-
-
-/* -- X11 forwarding */
-
-/* Maximum number of fake X11 displays to try. */
-#define MAX_DISPLAYS  1000
-
-/* Saved X11 authentication protocol name. */
-static char *x11_saved_proto = NULL;
-
-/* Saved X11 authentication data.  This is the real data. */
-static char *x11_saved_data = NULL;
-static u_int x11_saved_data_len = 0;
-
-/*
- * Fake X11 authentication data.  This is what the server will be sending us;
- * we should replace any occurrences of this by the real data.
- */
-static u_char *x11_fake_data = NULL;
-static u_int x11_fake_data_len;
-
-
-/* -- agent forwarding */
-
-#define	NUM_SOCKS	10
-
-/* AF_UNSPEC or AF_INET or AF_INET6 */
-static int IPv4or6 = AF_UNSPEC;
-
-/* helper */
-static void port_open_helper(Channel *c, char *rtype);
-
-/* -- channel core */
-
-Channel *
-channel_lookup(int id)
-{
-	Channel *c;
-
-	if (id < 0 || id >= channels_alloc) {
-		log("channel_lookup: %d: bad id", id);
-		return NULL;
-	}
-	c = channels[id];
-	if (c == NULL) {
-		log("channel_lookup: %d: bad id: channel free", id);
-		return NULL;
-	}
-	return c;
-}
-
-/*
- * Register filedescriptors for a channel, used when allocating a channel or
- * when the channel consumer/producer is ready, e.g. shell exec'd
- */
-
-static void
-channel_register_fds(Channel *c, int rfd, int wfd, int efd,
-    int extusage, int nonblock)
-{
-	/* Update the maximum file descriptor value. */
-	channel_max_fd = MAX(channel_max_fd, rfd);
-	channel_max_fd = MAX(channel_max_fd, wfd);
-	channel_max_fd = MAX(channel_max_fd, efd);
-
-	/* XXX set close-on-exec -markus */
-
-	c->rfd = rfd;
-	c->wfd = wfd;
-	c->sock = (rfd == wfd) ? rfd : -1;
-	c->efd = efd;
-	c->extended_usage = extusage;
-
-	/* XXX ugly hack: nonblock is only set by the server */
-	if (nonblock && isatty(c->rfd)) {
-		debug("channel %d: rfd %d isatty", c->self, c->rfd);
-		c->isatty = 1;
-		if (!isatty(c->wfd)) {
-			error("channel %d: wfd %d is not a tty?",
-			    c->self, c->wfd);
-		}
-	} else {
-		c->isatty = 0;
-	}
-	c->wfd_isatty = isatty(c->wfd);
-
-	/* enable nonblocking mode */
-	if (nonblock) {
-		if (rfd != -1)
-			set_nonblock(rfd);
-		if (wfd != -1)
-			set_nonblock(wfd);
-		if (efd != -1)
-			set_nonblock(efd);
-	}
-}
-
-/*
- * Allocate a new channel object and set its type and socket. This will cause
- * remote_name to be freed.
- */
-
-Channel *
-channel_new(char *ctype, int type, int rfd, int wfd, int efd,
-    u_int window, u_int maxpack, int extusage, char *remote_name, int nonblock)
-{
-	int i, found;
-	Channel *c;
-
-	/* Do initial allocation if this is the first call. */
-	if (channels_alloc == 0) {
-		channels_alloc = 10;
-		channels = xmalloc(channels_alloc * sizeof(Channel *));
-		for (i = 0; i < channels_alloc; i++)
-			channels[i] = NULL;
-		fatal_add_cleanup((void (*) (void *)) channel_free_all, NULL);
-	}
-	/* Try to find a free slot where to put the new channel. */
-	for (found = -1, i = 0; i < channels_alloc; i++)
-		if (channels[i] == NULL) {
-			/* Found a free slot. */
-			found = i;
-			break;
-		}
-	if (found == -1) {
-		/* There are no free slots.  Take last+1 slot and expand the array.  */
-		found = channels_alloc;
-		if (channels_alloc > 10000)
-			fatal("channel_new: internal error: channels_alloc %d "
-			    "too big.", channels_alloc);
-		channels = xrealloc(channels,
-		    (channels_alloc + 10) * sizeof(Channel *));
-		channels_alloc += 10;
-		debug2("channel: expanding %d", channels_alloc);
-		for (i = found; i < channels_alloc; i++)
-			channels[i] = NULL;
-	}
-	/* Initialize and return new channel. */
-	c = channels[found] = xmalloc(sizeof(Channel));
-	memset(c, 0, sizeof(Channel));
-	buffer_init(&c->input);
-	buffer_init(&c->output);
-	buffer_init(&c->extended);
-	c->ostate = CHAN_OUTPUT_OPEN;
-	c->istate = CHAN_INPUT_OPEN;
-	c->flags = 0;
-	channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
-	c->self = found;
-	c->type = type;
-	c->ctype = ctype;
-	c->local_window = window;
-	c->local_window_max = window;
-	c->local_consumed = 0;
-	c->local_maxpacket = maxpack;
-	c->remote_id = -1;
-	c->remote_name = remote_name;
-	c->remote_window = 0;
-	c->remote_maxpacket = 0;
-	c->force_drain = 0;
-	c->single_connection = 0;
-	c->detach_user = NULL;
-	c->confirm = NULL;
-	c->input_filter = NULL;
-	c->delayed = 1;		/* prevent call to channel_post handler */
-	debug("channel %d: new [%s]", found, remote_name);
-	return c;
-}
-
-static int
-channel_find_maxfd(void)
-{
-	int i, max = 0;
-	Channel *c;
-
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c != NULL) {
-			max = MAX(max, c->rfd);
-			max = MAX(max, c->wfd);
-			max = MAX(max, c->efd);
-		}
-	}
-	return max;
-}
-
-int
-channel_close_fd(int *fdp)
-{
-	int ret = 0, fd = *fdp;
-
-	if (fd != -1) {
-		ret = close(fd);
-		*fdp = -1;
-		if (fd == channel_max_fd)
-			channel_max_fd = channel_find_maxfd();
-	}
-	return ret;
-}
-
-/* Close all channel fd/socket. */
-
-static void
-channel_close_fds(Channel *c)
-{
-	debug3("channel_close_fds: channel %d: r %d w %d e %d",
-	    c->self, c->rfd, c->wfd, c->efd);
-
-	channel_close_fd(&c->sock);
-	channel_close_fd(&c->rfd);
-	channel_close_fd(&c->wfd);
-	channel_close_fd(&c->efd);
-}
-
-/* Free the channel and close its fd/socket. */
-
-void
-channel_free(Channel *c)
-{
-	char *s;
-	int i, n;
-
-	for (n = 0, i = 0; i < channels_alloc; i++)
-		if (channels[i])
-			n++;
-	debug("channel_free: channel %d: %s, nchannels %d", c->self,
-	    c->remote_name ? c->remote_name : "???", n);
-
-	s = channel_open_message();
-	debug3("channel_free: status: %s", s);
-	xfree(s);
-
-	if (c->sock != -1)
-		shutdown(c->sock, SHUT_RDWR);
-	channel_close_fds(c);
-	buffer_free(&c->input);
-	buffer_free(&c->output);
-	buffer_free(&c->extended);
-	if (c->remote_name) {
-		xfree(c->remote_name);
-		c->remote_name = NULL;
-	}
-	channels[c->self] = NULL;
-	xfree(c);
-}
-
-void
-channel_free_all(void)
-{
-	int i;
-
-	for (i = 0; i < channels_alloc; i++)
-		if (channels[i] != NULL)
-			channel_free(channels[i]);
-}
-
-/*
- * Closes the sockets/fds of all channels.  This is used to close extra file
- * descriptors after a fork.
- */
-
-void
-channel_close_all(void)
-{
-	int i;
-
-	for (i = 0; i < channels_alloc; i++)
-		if (channels[i] != NULL)
-			channel_close_fds(channels[i]);
-}
-
-/*
- * Stop listening to channels.
- */
-
-void
-channel_stop_listening(void)
-{
-	int i;
-	Channel *c;
-
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c != NULL) {
-			switch (c->type) {
-			case SSH_CHANNEL_AUTH_SOCKET:
-			case SSH_CHANNEL_PORT_LISTENER:
-			case SSH_CHANNEL_RPORT_LISTENER:
-			case SSH_CHANNEL_X11_LISTENER:
-				channel_close_fd(&c->sock);
-				channel_free(c);
-				break;
-			}
-		}
-	}
-}
-
-/*
- * Returns true if no channel has too much buffered data, and false if one or
- * more channel is overfull.
- */
-
-int
-channel_not_very_much_buffered_data(void)
-{
-	u_int i;
-	Channel *c;
-
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c != NULL && c->type == SSH_CHANNEL_OPEN) {
-#if 0
-			if (!compat20 &&
-			    buffer_len(&c->input) > packet_get_maxsize()) {
-				debug("channel %d: big input buffer %d",
-				    c->self, buffer_len(&c->input));
-				return 0;
-			}
-#endif
-			if (buffer_len(&c->output) > packet_get_maxsize()) {
-				debug("channel %d: big output buffer %d > %d",
-				    c->self, buffer_len(&c->output),
-				    packet_get_maxsize());
-				return 0;
-			}
-		}
-	}
-	return 1;
-}
-
-/* Returns true if any channel is still open. */
-
-int
-channel_still_open(void)
-{
-	int i;
-	Channel *c;
-
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c == NULL)
-			continue;
-		switch (c->type) {
-		case SSH_CHANNEL_X11_LISTENER:
-		case SSH_CHANNEL_PORT_LISTENER:
-		case SSH_CHANNEL_RPORT_LISTENER:
-		case SSH_CHANNEL_CLOSED:
-		case SSH_CHANNEL_AUTH_SOCKET:
-		case SSH_CHANNEL_DYNAMIC:
-		case SSH_CHANNEL_CONNECTING:
-		case SSH_CHANNEL_ZOMBIE:
-			continue;
-		case SSH_CHANNEL_LARVAL:
-			if (!compat20)
-				fatal("cannot happen: SSH_CHANNEL_LARVAL");
-			continue;
-		case SSH_CHANNEL_OPENING:
-		case SSH_CHANNEL_OPEN:
-		case SSH_CHANNEL_X11_OPEN:
-			return 1;
-		case SSH_CHANNEL_INPUT_DRAINING:
-		case SSH_CHANNEL_OUTPUT_DRAINING:
-			if (!compat13)
-				fatal("cannot happen: OUT_DRAIN");
-			return 1;
-		default:
-			fatal("channel_still_open: bad channel type %d", c->type);
-			/* NOTREACHED */
-		}
-	}
-	return 0;
-}
-
-/* Returns the id of an open channel suitable for keepaliving */
-
-int
-channel_find_open(void)
-{
-	int i;
-	Channel *c;
-
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c == NULL)
-			continue;
-		switch (c->type) {
-		case SSH_CHANNEL_CLOSED:
-		case SSH_CHANNEL_DYNAMIC:
-		case SSH_CHANNEL_X11_LISTENER:
-		case SSH_CHANNEL_PORT_LISTENER:
-		case SSH_CHANNEL_RPORT_LISTENER:
-		case SSH_CHANNEL_OPENING:
-		case SSH_CHANNEL_CONNECTING:
-		case SSH_CHANNEL_ZOMBIE:
-			continue;
-		case SSH_CHANNEL_LARVAL:
-		case SSH_CHANNEL_AUTH_SOCKET:
-		case SSH_CHANNEL_OPEN:
-		case SSH_CHANNEL_X11_OPEN:
-			return i;
-		case SSH_CHANNEL_INPUT_DRAINING:
-		case SSH_CHANNEL_OUTPUT_DRAINING:
-			if (!compat13)
-				fatal("cannot happen: OUT_DRAIN");
-			return i;
-		default:
-			fatal("channel_find_open: bad channel type %d", c->type);
-			/* NOTREACHED */
-		}
-	}
-	return -1;
-}
-
-
-/*
- * Returns a message describing the currently open forwarded connections,
- * suitable for sending to the client.  The message contains crlf pairs for
- * newlines.
- */
-
-char *
-channel_open_message(void)
-{
-	Buffer buffer;
-	Channel *c;
-	char buf[1024], *cp;
-	int i;
-
-	buffer_init(&buffer);
-	snprintf(buf, sizeof buf, "The following connections are open:\r\n");
-	buffer_append(&buffer, buf, strlen(buf));
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c == NULL)
-			continue;
-		switch (c->type) {
-		case SSH_CHANNEL_X11_LISTENER:
-		case SSH_CHANNEL_PORT_LISTENER:
-		case SSH_CHANNEL_RPORT_LISTENER:
-		case SSH_CHANNEL_CLOSED:
-		case SSH_CHANNEL_AUTH_SOCKET:
-		case SSH_CHANNEL_ZOMBIE:
-			continue;
-		case SSH_CHANNEL_LARVAL:
-		case SSH_CHANNEL_OPENING:
-		case SSH_CHANNEL_CONNECTING:
-		case SSH_CHANNEL_DYNAMIC:
-		case SSH_CHANNEL_OPEN:
-		case SSH_CHANNEL_X11_OPEN:
-		case SSH_CHANNEL_INPUT_DRAINING:
-		case SSH_CHANNEL_OUTPUT_DRAINING:
-			snprintf(buf, sizeof buf, "  #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
-			    c->self, c->remote_name,
-			    c->type, c->remote_id,
-			    c->istate, buffer_len(&c->input),
-			    c->ostate, buffer_len(&c->output),
-			    c->rfd, c->wfd);
-			buffer_append(&buffer, buf, strlen(buf));
-			continue;
-		default:
-			fatal("channel_open_message: bad channel type %d", c->type);
-			/* NOTREACHED */
-		}
-	}
-	buffer_append(&buffer, "\0", 1);
-	cp = xstrdup(buffer_ptr(&buffer));
-	buffer_free(&buffer);
-	return cp;
-}
-
-void
-channel_send_open(int id)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL) {
-		log("channel_send_open: %d: bad id", id);
-		return;
-	}
-	debug("send channel open %d", id);
-	packet_start(SSH2_MSG_CHANNEL_OPEN);
-	packet_put_cstring(c->ctype);
-	packet_put_int(c->self);
-	packet_put_int(c->local_window);
-	packet_put_int(c->local_maxpacket);
-	packet_send();
-}
-
-void
-channel_request_start(int local_id, char *service, int wantconfirm)
-{
-	Channel *c = channel_lookup(local_id);
-
-	debug("channel request %d: %s", local_id, service);
-	if (c == NULL) {
-		log("channel_request_start: %d: unknown channel id", local_id);
-		return;
-	}
-	packet_start(SSH2_MSG_CHANNEL_REQUEST);
-	packet_put_int(c->remote_id);
-	packet_put_cstring(service);
-	packet_put_char(wantconfirm);
-}
-void
-channel_register_confirm(int id, channel_callback_fn *fn)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL) {
-		log("channel_register_comfirm: %d: bad id", id);
-		return;
-	}
-	c->confirm = fn;
-}
-void
-channel_register_cleanup(int id, channel_callback_fn *fn)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL) {
-		log("channel_register_cleanup: %d: bad id", id);
-		return;
-	}
-	c->detach_user = fn;
-}
-void
-channel_cancel_cleanup(int id)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL) {
-		log("channel_cancel_cleanup: %d: bad id", id);
-		return;
-	}
-	c->detach_user = NULL;
-}
-void
-channel_register_filter(int id, channel_filter_fn *fn)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL) {
-		log("channel_register_filter: %d: bad id", id);
-		return;
-	}
-	c->input_filter = fn;
-}
-
-void
-channel_set_fds(int id, int rfd, int wfd, int efd,
-    int extusage, int nonblock, u_int window_max)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
-		fatal("channel_activate for non-larval channel %d.", id);
-	channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
-	c->type = SSH_CHANNEL_OPEN;
-	c->local_window = c->local_window_max = window_max;
-	packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
-	packet_put_int(c->remote_id);
-	packet_put_int(c->local_window);
-	packet_send();
-}
-
-void
-channel_set_wait_for_exit(int id, int wait_for_exit)
-{
-	Channel *c = channel_lookup(id);
-
-	if (c == NULL || c->type != SSH_CHANNEL_OPEN)
-		fatal("channel_set_wait_for_exit for non-open channel %d.", id);
-
-	debug3("channel_set_wait_for_exit %d, %d (type: %d)", id, wait_for_exit, c->type);
-	c->wait_for_exit = wait_for_exit;
-}
-
-/*
- * 'channel_pre*' are called just before select() to add any bits relevant to
- * channels in the select bitmasks.
- */
-/*
- * 'channel_post*': perform any appropriate operations for channels which
- * have events pending.
- */
-typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
-chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
-chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
-
-static void
-channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	FD_SET(c->sock, readset);
-}
-
-static void
-channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	debug3("channel %d: waiting for connection", c->self);
-	FD_SET(c->sock, writeset);
-}
-
-static void
-channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	if (buffer_len(&c->input) < packet_get_maxsize())
-		FD_SET(c->sock, readset);
-	if (buffer_len(&c->output) > 0)
-		FD_SET(c->sock, writeset);
-}
-
-static void
-channel_pre_open(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	u_int limit = compat20 ? c->remote_window : packet_get_maxsize();
-
-	if (c->istate == CHAN_INPUT_OPEN &&
-	    limit > 0 &&
-	    buffer_len(&c->input) < limit &&
-	    buffer_check_alloc(&c->input, CHAN_RBUF))
-		FD_SET(c->rfd, readset);
-	if (c->ostate == CHAN_OUTPUT_OPEN ||
-	    c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
-		if (buffer_len(&c->output) > 0) {
-			FD_SET(c->wfd, writeset);
-		} else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
-			if (CHANNEL_EFD_OUTPUT_ACTIVE(c))
-			       debug2("channel %d: obuf_empty delayed efd %d/(%d)",
-				   c->self, c->efd, buffer_len(&c->extended));
-			else
-				chan_obuf_empty(c);
-		}
-	}
-	/** XXX check close conditions, too */
-	if (compat20 && c->efd != -1) {
-		if (c->extended_usage == CHAN_EXTENDED_WRITE &&
-		    buffer_len(&c->extended) > 0)
-			FD_SET(c->efd, writeset);
-		else if (!(c->flags & CHAN_EOF_SENT) &&
-		    c->extended_usage == CHAN_EXTENDED_READ &&
-		    buffer_len(&c->extended) < c->remote_window)
-			FD_SET(c->efd, readset);
-	}
-}
-
-static void
-channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	if (buffer_len(&c->input) == 0) {
-		packet_start(SSH_MSG_CHANNEL_CLOSE);
-		packet_put_int(c->remote_id);
-		packet_send();
-		c->type = SSH_CHANNEL_CLOSED;
-		debug("channel %d: closing after input drain.", c->self);
-	}
-}
-
-static void
-channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	if (buffer_len(&c->output) == 0)
-		chan_mark_dead(c);
-	else
-		FD_SET(c->sock, writeset);
-}
-
-/*
- * This is a special state for X11 authentication spoofing.  An opened X11
- * connection (when authentication spoofing is being done) remains in this
- * state until the first packet has been completely read.  The authentication
- * data in that packet is then substituted by the real data if it matches the
- * fake data, and the channel is put into normal mode.
- * XXX All this happens at the client side.
- * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
- */
-static int
-x11_open_helper(Buffer *b)
-{
-	u_char *ucp;
-	u_int proto_len, data_len;
-
-	/* Check if the fixed size part of the packet is in buffer. */
-	if (buffer_len(b) < 12)
-		return 0;
-
-	/* Parse the lengths of variable-length fields. */
-	ucp = buffer_ptr(b);
-	if (ucp[0] == 0x42) {	/* Byte order MSB first. */
-		proto_len = 256 * ucp[6] + ucp[7];
-		data_len = 256 * ucp[8] + ucp[9];
-	} else if (ucp[0] == 0x6c) {	/* Byte order LSB first. */
-		proto_len = ucp[6] + 256 * ucp[7];
-		data_len = ucp[8] + 256 * ucp[9];
-	} else {
-		debug("Initial X11 packet contains bad byte order byte: 0x%x",
-		    ucp[0]);
-		return -1;
-	}
-
-	/* Check if the whole packet is in buffer. */
-	if (buffer_len(b) <
-	    12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
-		return 0;
-
-	/* Check if authentication protocol matches. */
-	if (proto_len != strlen(x11_saved_proto) ||
-	    memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
-		debug("X11 connection uses different authentication protocol.");
-		return -1;
-	}
-	/* Check if authentication data matches our fake data. */
-	if (data_len != x11_fake_data_len ||
-	    memcmp(ucp + 12 + ((proto_len + 3) & ~3),
-		x11_fake_data, x11_fake_data_len) != 0) {
-		debug("X11 auth data does not match fake data.");
-		return -1;
-	}
-	/* Check fake data length */
-	if (x11_fake_data_len != x11_saved_data_len) {
-		error("X11 fake_data_len %d != saved_data_len %d",
-		    x11_fake_data_len, x11_saved_data_len);
-		return -1;
-	}
-	/*
-	 * Received authentication protocol and data match
-	 * our fake data. Substitute the fake data with real
-	 * data.
-	 */
-	memcpy(ucp + 12 + ((proto_len + 3) & ~3),
-	    x11_saved_data, x11_saved_data_len);
-	return 1;
-}
-
-static void
-channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	int ret = x11_open_helper(&c->output);
-
-	if (ret == 1) {
-		/* Start normal processing for the channel. */
-		c->type = SSH_CHANNEL_OPEN;
-		channel_pre_open_13(c, readset, writeset);
-	} else if (ret == -1) {
-		/*
-		 * We have received an X11 connection that has bad
-		 * authentication information.
-		 */
-		log("X11 connection rejected because of wrong authentication.");
-		buffer_clear(&c->input);
-		buffer_clear(&c->output);
-		channel_close_fd(&c->sock);
-		c->sock = -1;
-		c->type = SSH_CHANNEL_CLOSED;
-		packet_start(SSH_MSG_CHANNEL_CLOSE);
-		packet_put_int(c->remote_id);
-		packet_send();
-	}
-}
-
-static void
-channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	int ret = x11_open_helper(&c->output);
-
-	/* c->force_drain = 1; */
-
-	if (ret == 1) {
-		c->type = SSH_CHANNEL_OPEN;
-		channel_pre_open(c, readset, writeset);
-	} else if (ret == -1) {
-		log("X11 connection rejected because of wrong authentication.");
-		debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
-		chan_read_failed(c);
-		buffer_clear(&c->input);
-		chan_ibuf_empty(c);
-		buffer_clear(&c->output);
-		/* for proto v1, the peer will send an IEOF */
-		if (compat20)
-			chan_write_failed(c);
-		else
-			c->type = SSH_CHANNEL_OPEN;
-		debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
-	}
-}
-
-/* try to decode a socks4 header */
-static int
-channel_decode_socks4(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	char *p, *host;
-	int len, have, i, found;
-	char username[256];
-	struct {
-		u_int8_t version;
-		u_int8_t command;
-		u_int16_t dest_port;
-		struct in_addr dest_addr;
-	} s4_req, s4_rsp;
-
-	debug2("channel %d: decode socks4", c->self);
-
-	have = buffer_len(&c->input);
-	len = sizeof(s4_req);
-	if (have < len)
-		return 0;
-	p = buffer_ptr(&c->input);
-	for (found = 0, i = len; i < have; i++) {
-		if (p[i] == '\0') {
-			found = 1;
-			break;
-		}
-		if (i > 1024) {
-			/* the peer is probably sending garbage */
-			debug("channel %d: decode socks4: too long",
-			    c->self);
-			return -1;
-		}
-	}
-	if (!found)
-		return 0;
-	buffer_get(&c->input, (char *)&s4_req.version, 1);
-	buffer_get(&c->input, (char *)&s4_req.command, 1);
-	buffer_get(&c->input, (char *)&s4_req.dest_port, 2);
-	buffer_get(&c->input, (char *)&s4_req.dest_addr, 4);
-	have = buffer_len(&c->input);
-	p = buffer_ptr(&c->input);
-	len = strlen(p);
-	debug2("channel %d: decode socks4: user %s/%d", c->self, p, len);
-	if (len > have)
-		fatal("channel %d: decode socks4: len %d > have %d",
-		    c->self, len, have);
-	strlcpy(username, p, sizeof(username));
-	buffer_consume(&c->input, len);
-	buffer_consume(&c->input, 1);		/* trailing '\0' */
-
-	host = inet_ntoa(s4_req.dest_addr);
-	strlcpy(c->path, host, sizeof(c->path));
-	c->host_port = ntohs(s4_req.dest_port);
-
-	debug("channel %d: dynamic request: socks4 host %s port %u command %u",
-	    c->self, host, c->host_port, s4_req.command);
-
-	if (s4_req.command != 1) {
-		debug("channel %d: cannot handle: socks4 cn %d",
-		    c->self, s4_req.command);
-		return -1;
-	}
-	s4_rsp.version = 0;			/* vn: 0 for reply */
-	s4_rsp.command = 90;			/* cd: req granted */
-	s4_rsp.dest_port = 0;			/* ignored */
-	s4_rsp.dest_addr.s_addr = INADDR_ANY;	/* ignored */
-	buffer_append(&c->output, (char *)&s4_rsp, sizeof(s4_rsp));
-	return 1;
-}
-
-/* try to decode a socks5 header */
-#define SSH_SOCKS5_AUTHDONE	0x1000
-#define SSH_SOCKS5_NOAUTH	0x00
-#define SSH_SOCKS5_IPV4		0x01
-#define SSH_SOCKS5_DOMAIN	0x03
-#define SSH_SOCKS5_IPV6		0x04
-#define SSH_SOCKS5_CONNECT	0x01
-#define SSH_SOCKS5_SUCCESS	0x00
-
-/* ARGSUSED */
-static int
-channel_decode_socks5(Channel *c, fd_set *readset, fd_set *writeset)
-{
-	struct {
-		u_int8_t version;
-		u_int8_t command;
-		u_int8_t reserved;
-		u_int8_t atyp;
-	} s5_req, s5_rsp;
-	u_int16_t dest_port;
-	u_char *p, dest_addr[255+1];
-	u_int have, need, i, found, nmethods, addrlen;
-	struct in_addr bnd_addr;
-	int af;
-
-	debug2("channel %d: decode socks5", c->self);
-	p = buffer_ptr(&c->input);
-	if (p[0] != 0x05)
-		return -1;
-	have = buffer_len(&c->input);
-	if (!(c->flags & SSH_SOCKS5_AUTHDONE)) {
-		/* format: ver | nmethods | methods */
-		if (have < 2)
-			return 0;
-		nmethods = p[1];
-		if (have < nmethods + 2)
-			return 0;
-		/* look for method: "NO AUTHENTICATION REQUIRED" */
-		for (found = 0, i = 2 ; i < nmethods + 2; i++) {
-			if (p[i] == SSH_SOCKS5_NOAUTH) {
-				found = 1;
-				break;
-			}
-		}
-		if (!found) {
-			error("channel %d: socks5 authentication methods not implemented",
-			    c->self);
-			error("channel %d: forwarding failed: "
-			    "SSH_SOCKS5_NOAUTH method not found", c->self);
-			return -1;
-		}
-		buffer_consume(&c->input, nmethods + 2);
-		buffer_put_char(&c->output, 0x05);		/* version */
-		buffer_put_char(&c->output, SSH_SOCKS5_NOAUTH);	/* method */
-		FD_SET(c->sock, writeset);
-		c->flags |= SSH_SOCKS5_AUTHDONE;
-		debug2("channel %d: socks5 auth done", c->self);
-		return 0;				/* need more */
-	}
-	debug2("channel %d: socks5 post auth", c->self);
-	if (have < sizeof(s5_req)+1)
-		return 0;			/* need more */
-	memcpy(&s5_req, p, sizeof(s5_req));
-	if (s5_req.version != 0x05 ||
-	    s5_req.command != SSH_SOCKS5_CONNECT ||
-	    s5_req.reserved != 0x00) {
-		error("channel %d: forwarding failed: "
-		    "only socks5 connect is supported", c->self);
-		return -1;
-	}
-	switch (s5_req.atyp){
-	case SSH_SOCKS5_IPV4:
-		addrlen = 4;
-		af = AF_INET;
-		break;
-	case SSH_SOCKS5_DOMAIN:
-		addrlen = p[sizeof(s5_req)];
-		af = -1;
-		break;
-	case SSH_SOCKS5_IPV6:
-		addrlen = 16;
-		af = AF_INET6;
-		break;
-	default:
-		error("channel %d: forwarding failed: "
-		    "bad socks5 atyp %d", c->self, s5_req.atyp);
-		return -1;
-	}
-	need = sizeof(s5_req) + addrlen + 2;
-	if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
-		need++;
-	if (have < need)
-		return 0;
-	buffer_consume(&c->input, sizeof(s5_req));
-	if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
-		buffer_consume(&c->input, 1);    /* host string length */
-	buffer_get(&c->input, (char *)&dest_addr, addrlen);
-	buffer_get(&c->input, (char *)&dest_port, 2);
-	dest_addr[addrlen] = '\0';
-	if (s5_req.atyp == SSH_SOCKS5_DOMAIN)
-		strlcpy(c->path, (char *)dest_addr, sizeof(c->path));
-	else if (inet_ntop(af, dest_addr, c->path, sizeof(c->path)) == NULL)
-		return -1;
-	c->host_port = ntohs(dest_port);
-
-	debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
-	    c->self, c->path, c->host_port, s5_req.command);
-
-	s5_rsp.version = 0x05;
-	s5_rsp.command = SSH_SOCKS5_SUCCESS;
-	s5_rsp.reserved = 0;			/* ignored */
-	s5_rsp.atyp = SSH_SOCKS5_IPV4;
-	bzero(&bnd_addr, sizeof(bnd_addr));
-	bnd_addr.s_addr = htonl(INADDR_ANY);
-	dest_port = 0;				/* ignored */
-
-	buffer_append(&c->output, &s5_rsp, sizeof(s5_rsp));
-	buffer_append(&c->output, &bnd_addr, sizeof(struct in_addr));
-	buffer_append(&c->output, &dest_port, sizeof(dest_port));
-	return 1;
-}
-
-/* dynamic port forwarding */
-static void
-channel_pre_dynamic(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	u_char *p;
-	int have, ret;
-
-	have = buffer_len(&c->input);
-	debug2("channel %d: pre_dynamic: have %d", c->self, have);
-	/* buffer_dump(&c->input); */
-	/* check if the fixed size part of the packet is in buffer. */
-	if (have < 3) {
-		/* need more */
-		FD_SET(c->sock, readset);
-		return;
-	}
-	/* try to guess the protocol */
-	p = buffer_ptr(&c->input);
-	switch (p[0]) {
-	case 0x04:
-		ret = channel_decode_socks4(c, readset, writeset);
-		break;
-	case 0x05:
-		ret = channel_decode_socks5(c, readset, writeset);
-		break;
-	default:
-		error("channel %d: forwarding failed: unknown socks "
-		    "version 0x%02X", c->self, p[0]);
-		ret = -1;
-		break;
-	}
-	if (ret < 0) {
-		chan_mark_dead(c);
-	} else if (ret == 0) {
-		debug2("channel %d: pre_dynamic: need more", c->self);
-		/* need more */
-		FD_SET(c->sock, readset);
-	} else {
-		/* switch to the next state */
-		c->type = SSH_CHANNEL_OPENING;
-		port_open_helper(c, "direct-tcpip");
-	}
-}
-
-/* This is our fake X11 server socket. */
-static void
-channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	Channel *nc;
-	struct sockaddr addr;
-	int newsock;
-	socklen_t addrlen;
-	char buf[16384], *remote_ipaddr;
-	int remote_port;
-
-	if (FD_ISSET(c->sock, readset)) {
-		debug("X11 connection requested.");
-		addrlen = sizeof(addr);
-		newsock = accept(c->sock, &addr, &addrlen);
-		if (c->single_connection) {
-			debug("single_connection: closing X11 listener.");
-			channel_close_fd(&c->sock);
-			chan_mark_dead(c);
-		}
-		if (newsock < 0) {
-			error("accept: %.100s", strerror(errno));
-			return;
-		}
-		set_nodelay(newsock);
-		remote_ipaddr = get_peer_ipaddr(newsock);
-		remote_port = get_peer_port(newsock);
-		snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
-		    remote_ipaddr, remote_port);
-
-		nc = channel_new("accepted x11 socket",
-		    SSH_CHANNEL_OPENING, newsock, newsock, -1,
-		    c->local_window_max, c->local_maxpacket,
-		    0, xstrdup(buf), 1);
-		if (compat20) {
-			packet_start(SSH2_MSG_CHANNEL_OPEN);
-			packet_put_cstring("x11");
-			packet_put_int(nc->self);
-			packet_put_int(nc->local_window_max);
-			packet_put_int(nc->local_maxpacket);
-			/* originator ipaddr and port */
-			packet_put_cstring(remote_ipaddr);
-			if (datafellows & SSH_BUG_X11FWD) {
-				debug("ssh2 x11 bug compat mode");
-			} else {
-				packet_put_int(remote_port);
-			}
-			packet_send();
-		} else {
-			packet_start(SSH_SMSG_X11_OPEN);
-			packet_put_int(nc->self);
-			if (packet_get_protocol_flags() &
-			    SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
-				packet_put_cstring(buf);
-			packet_send();
-		}
-		xfree(remote_ipaddr);
-	}
-}
-
-static void
-port_open_helper(Channel *c, char *rtype)
-{
-	int direct;
-	char buf[1024];
-	char *remote_ipaddr = get_peer_ipaddr(c->sock);
-	u_short remote_port = get_peer_port(c->sock);
-
-	direct = (strcmp(rtype, "direct-tcpip") == 0);
-
-	snprintf(buf, sizeof buf,
-	    "%s: listening port %d for %.100s port %d, "
-	    "connect from %.200s port %d",
-	    rtype, c->listening_port, c->path, c->host_port,
-	    remote_ipaddr, remote_port);
-
-	xfree(c->remote_name);
-	c->remote_name = xstrdup(buf);
-
-	if (compat20) {
-		packet_start(SSH2_MSG_CHANNEL_OPEN);
-		packet_put_cstring(rtype);
-		packet_put_int(c->self);
-		packet_put_int(c->local_window_max);
-		packet_put_int(c->local_maxpacket);
-		if (direct) {
-			/* target host, port */
-			packet_put_cstring(c->path);
-			packet_put_int(c->host_port);
-		} else {
-			/* listen address, port */
-			packet_put_cstring(c->path);
-			packet_put_int(c->listening_port);
-		}
-		/* originator host and port */
-		packet_put_cstring(remote_ipaddr);
-		packet_put_int(remote_port);
-		packet_send();
-	} else {
-		packet_start(SSH_MSG_PORT_OPEN);
-		packet_put_int(c->self);
-		packet_put_cstring(c->path);
-		packet_put_int(c->host_port);
-		if (packet_get_protocol_flags() &
-		    SSH_PROTOFLAG_HOST_IN_FWD_OPEN)
-			packet_put_cstring(c->remote_name);
-		packet_send();
-	}
-	xfree(remote_ipaddr);
-}
-
-/*
- * This socket is listening for connections to a forwarded TCP/IP port.
- */
-static void
-channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	Channel *nc;
-	struct sockaddr addr;
-	int newsock, nextstate;
-	socklen_t addrlen;
-	char *rtype;
-
-	if (FD_ISSET(c->sock, readset)) {
-		debug("Connection to port %d forwarding "
-		    "to %.100s port %d requested.",
-		    c->listening_port, c->path, c->host_port);
-
-		if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
-			nextstate = SSH_CHANNEL_OPENING;
-			rtype = "forwarded-tcpip";
-		} else {
-			if (c->host_port == 0) {
-				nextstate = SSH_CHANNEL_DYNAMIC;
-				rtype = "dynamic-tcpip";
-			} else {
-				nextstate = SSH_CHANNEL_OPENING;
-				rtype = "direct-tcpip";
-			}
-		}
-
-		addrlen = sizeof(addr);
-		newsock = accept(c->sock, &addr, &addrlen);
-		if (newsock < 0) {
-			error("accept: %.100s", strerror(errno));
-			return;
-		}
-		set_nodelay(newsock);
-		nc = channel_new(rtype,
-		    nextstate, newsock, newsock, -1,
-		    c->local_window_max, c->local_maxpacket,
-		    0, xstrdup(rtype), 1);
-		nc->listening_port = c->listening_port;
-		nc->host_port = c->host_port;
-		strlcpy(nc->path, c->path, sizeof(nc->path));
-
-		if (nextstate != SSH_CHANNEL_DYNAMIC)
-			port_open_helper(nc, rtype);
-	}
-}
-
-/*
- * This is the authentication agent socket listening for connections from
- * clients.
- */
-static void
-channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	Channel *nc;
-	char *name;
-	int newsock;
-	struct sockaddr addr;
-	socklen_t addrlen;
-
-	if (FD_ISSET(c->sock, readset)) {
-		addrlen = sizeof(addr);
-		newsock = accept(c->sock, &addr, &addrlen);
-		if (newsock < 0) {
-			error("accept from auth socket: %.100s", strerror(errno));
-			return;
-		}
-		name = xstrdup("accepted auth socket");
-		nc = channel_new("accepted auth socket",
-		    SSH_CHANNEL_OPENING, newsock, newsock, -1,
-		    c->local_window_max, c->local_maxpacket,
-		    0, name, 1);
-		if (compat20) {
-			packet_start(SSH2_MSG_CHANNEL_OPEN);
-			packet_put_cstring("auth-agent@openssh.com");
-			packet_put_int(nc->self);
-			packet_put_int(c->local_window_max);
-			packet_put_int(c->local_maxpacket);
-		} else {
-			packet_start(SSH_SMSG_AGENT_OPEN);
-			packet_put_int(nc->self);
-		}
-		packet_send();
-	}
-}
-
-static void
-channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	int err = 0;
-	socklen_t sz = sizeof(err);
-
-	if (FD_ISSET(c->sock, writeset)) {
-		if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, &err, &sz) < 0) {
-			err = errno;
-			error("getsockopt SO_ERROR failed");
-		}
-		if (err == 0) {
-			debug("channel %d: connected", c->self);
-			c->type = SSH_CHANNEL_OPEN;
-			if (compat20) {
-				packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
-				packet_put_int(c->remote_id);
-				packet_put_int(c->self);
-				packet_put_int(c->local_window);
-				packet_put_int(c->local_maxpacket);
-			} else {
-				packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
-				packet_put_int(c->remote_id);
-				packet_put_int(c->self);
-			}
-		} else {
-			debug("channel %d: not connected: %s",
-			    c->self, strerror(err));
-			if (compat20) {
-				packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
-				packet_put_int(c->remote_id);
-				packet_put_int(SSH2_OPEN_CONNECT_FAILED);
-				if (!(datafellows & SSH_BUG_OPENFAILURE)) {
-					packet_put_utf8_cstring(strerror(err));
-					packet_put_cstring("");
-				}
-			} else {
-				packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
-				packet_put_int(c->remote_id);
-			}
-			chan_mark_dead(c);
-		}
-		packet_send();
-	}
-}
-
-static int
-channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	char buf[CHAN_RBUF];
-	int len;
-
-	if (c->rfd != -1 &&
-	    FD_ISSET(c->rfd, readset)) {
-		len = read(c->rfd, buf, sizeof(buf));
-		if (len < 0 && (errno == EINTR || errno == EAGAIN))
-			return 1;
-		if (len <= 0) {
-			debug("channel %d: read<=0 rfd %d len %d",
-			    c->self, c->rfd, len);
-			if (c->type != SSH_CHANNEL_OPEN) {
-				debug("channel %d: not open", c->self);
-				chan_mark_dead(c);
-				return -1;
-			} else if (compat13) {
-				buffer_clear(&c->output);
-				c->type = SSH_CHANNEL_INPUT_DRAINING;
-				debug("channel %d: input draining.", c->self);
-			} else {
-				chan_read_failed(c);
-			}
-			return -1;
-		}
-		if (c->input_filter != NULL) {
-			if (c->input_filter(c, buf, len) == -1) {
-				debug("channel %d: filter stops", c->self);
-				chan_read_failed(c);
-			}
-		} else {
-			buffer_append(&c->input, buf, len);
-		}
-	}
-	return 1;
-}
-static int
-channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	struct termios tio;
-	u_char *data;
-	u_int dlen;
-	int len;
-
-	/* Send buffered output data to the socket. */
-	if (c->wfd != -1 &&
-	    FD_ISSET(c->wfd, writeset) &&
-	    buffer_len(&c->output) > 0) {
-		data = buffer_ptr(&c->output);
-		dlen = buffer_len(&c->output);
-#ifdef _AIX
-		/* XXX: Later AIX versions can't push as much data to tty */ 
-		if (compat20 && c->wfd_isatty && dlen > 8*1024)
-			dlen = 8*1024;
-#endif
-		len = write(c->wfd, data, dlen);
-		if (len < 0 && (errno == EINTR || errno == EAGAIN))
-			return 1;
-		if (len <= 0) {
-			if (c->type != SSH_CHANNEL_OPEN) {
-				debug("channel %d: not open", c->self);
-				chan_mark_dead(c);
-				return -1;
-			} else if (compat13) {
-				buffer_clear(&c->output);
-				debug("channel %d: input draining.", c->self);
-				c->type = SSH_CHANNEL_INPUT_DRAINING;
-			} else {
-				chan_write_failed(c);
-			}
-			return -1;
-		}
-		if (compat20 && c->isatty && dlen >= 1 && data[0] != '\r') {
-			if (tcgetattr(c->wfd, &tio) == 0 &&
-			    !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
-				/*
-				 * Simulate echo to reduce the impact of
-				 * traffic analysis. We need to match the
-				 * size of a SSH2_MSG_CHANNEL_DATA message
-				 * (4 byte channel id + data)
-				 */
-				packet_send_ignore(4 + len);
-				packet_send();
-			}
-		}
-		buffer_consume(&c->output, len);
-		if (compat20 && len > 0) {
-			c->local_consumed += len;
-		}
-	}
-	return 1;
-}
-static int
-channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	char buf[CHAN_RBUF];
-	int len;
-
-/** XXX handle drain efd, too */
-	if (c->efd != -1) {
-		if (c->extended_usage == CHAN_EXTENDED_WRITE &&
-		    FD_ISSET(c->efd, writeset) &&
-		    buffer_len(&c->extended) > 0) {
-			len = write(c->efd, buffer_ptr(&c->extended),
-			    buffer_len(&c->extended));
-			debug2("channel %d: written %d to efd %d",
-			    c->self, len, c->efd);
-			if (len < 0 && (errno == EINTR || errno == EAGAIN))
-				return 1;
-			if (len <= 0) {
-				debug2("channel %d: closing write-efd %d",
-				    c->self, c->efd);
-				channel_close_fd(&c->efd);
-			} else {
-				buffer_consume(&c->extended, len);
-				c->local_consumed += len;
-			}
-		} else if (c->extended_usage == CHAN_EXTENDED_READ &&
-		    FD_ISSET(c->efd, readset)) {
-			len = read(c->efd, buf, sizeof(buf));
-			debug2("channel %d: read %d from efd %d",
-			    c->self, len, c->efd);
-			if (len < 0 && (errno == EINTR || errno == EAGAIN))
-				return 1;
-			if (len <= 0) {
-				debug2("channel %d: closing read-efd %d",
-				    c->self, c->efd);
-				channel_close_fd(&c->efd);
-			} else {
-				buffer_append(&c->extended, buf, len);
-			}
-		}
-	}
-	return 1;
-}
-static int
-channel_check_window(Channel *c)
-{
-	if (c->type == SSH_CHANNEL_OPEN &&
-	    !(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
-	    c->local_window < c->local_window_max/2 &&
-	    c->local_consumed > 0) {
-		packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
-		packet_put_int(c->remote_id);
-		packet_put_int(c->local_consumed);
-		packet_send();
-		debug2("channel %d: window %d sent adjust %d",
-		    c->self, c->local_window,
-		    c->local_consumed);
-		c->local_window += c->local_consumed;
-		c->local_consumed = 0;
-	}
-	return 1;
-}
-
-static void
-channel_post_open(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	channel_handle_rfd(c, readset, writeset);
-	channel_handle_wfd(c, readset, writeset);
-	if (!compat20)
-		return;
-	channel_handle_efd(c, readset, writeset);
-	channel_check_window(c);
-}
-
-static void
-channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
-{
-	int len;
-
-	/* Send buffered output data to the socket. */
-	if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
-		len = write(c->sock, buffer_ptr(&c->output),
-			    buffer_len(&c->output));
-		if (len <= 0)
-			buffer_clear(&c->output);
-		else
-			buffer_consume(&c->output, len);
-	}
-}
-
-static void
-channel_handler_init_20(void)
-{
-	channel_pre[SSH_CHANNEL_OPEN] =			&channel_pre_open;
-	channel_pre[SSH_CHANNEL_X11_OPEN] =		&channel_pre_x11_open;
-	channel_pre[SSH_CHANNEL_PORT_LISTENER] =	&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_RPORT_LISTENER] =	&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_X11_LISTENER] =		&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_AUTH_SOCKET] =		&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_CONNECTING] =		&channel_pre_connecting;
-	channel_pre[SSH_CHANNEL_DYNAMIC] =		&channel_pre_dynamic;
-
-	channel_post[SSH_CHANNEL_OPEN] =		&channel_post_open;
-	channel_post[SSH_CHANNEL_PORT_LISTENER] =	&channel_post_port_listener;
-	channel_post[SSH_CHANNEL_RPORT_LISTENER] =	&channel_post_port_listener;
-	channel_post[SSH_CHANNEL_X11_LISTENER] =	&channel_post_x11_listener;
-	channel_post[SSH_CHANNEL_AUTH_SOCKET] =		&channel_post_auth_listener;
-	channel_post[SSH_CHANNEL_CONNECTING] =		&channel_post_connecting;
-	channel_post[SSH_CHANNEL_DYNAMIC] =		&channel_post_open;
-}
-
-static void
-channel_handler_init_13(void)
-{
-	channel_pre[SSH_CHANNEL_OPEN] =			&channel_pre_open_13;
-	channel_pre[SSH_CHANNEL_X11_OPEN] =		&channel_pre_x11_open_13;
-	channel_pre[SSH_CHANNEL_X11_LISTENER] =		&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_PORT_LISTENER] =	&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_AUTH_SOCKET] =		&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_INPUT_DRAINING] =	&channel_pre_input_draining;
-	channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] =	&channel_pre_output_draining;
-	channel_pre[SSH_CHANNEL_CONNECTING] =		&channel_pre_connecting;
-	channel_pre[SSH_CHANNEL_DYNAMIC] =		&channel_pre_dynamic;
-
-	channel_post[SSH_CHANNEL_OPEN] =		&channel_post_open;
-	channel_post[SSH_CHANNEL_X11_LISTENER] =	&channel_post_x11_listener;
-	channel_post[SSH_CHANNEL_PORT_LISTENER] =	&channel_post_port_listener;
-	channel_post[SSH_CHANNEL_AUTH_SOCKET] =		&channel_post_auth_listener;
-	channel_post[SSH_CHANNEL_OUTPUT_DRAINING] =	&channel_post_output_drain_13;
-	channel_post[SSH_CHANNEL_CONNECTING] =		&channel_post_connecting;
-	channel_post[SSH_CHANNEL_DYNAMIC] =		&channel_post_open;
-}
-
-static void
-channel_handler_init_15(void)
-{
-	channel_pre[SSH_CHANNEL_OPEN] =			&channel_pre_open;
-	channel_pre[SSH_CHANNEL_X11_OPEN] =		&channel_pre_x11_open;
-	channel_pre[SSH_CHANNEL_X11_LISTENER] =		&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_PORT_LISTENER] =	&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_AUTH_SOCKET] =		&channel_pre_listener;
-	channel_pre[SSH_CHANNEL_CONNECTING] =		&channel_pre_connecting;
-	channel_pre[SSH_CHANNEL_DYNAMIC] =		&channel_pre_dynamic;
-
-	channel_post[SSH_CHANNEL_X11_LISTENER] =	&channel_post_x11_listener;
-	channel_post[SSH_CHANNEL_PORT_LISTENER] =	&channel_post_port_listener;
-	channel_post[SSH_CHANNEL_AUTH_SOCKET] =		&channel_post_auth_listener;
-	channel_post[SSH_CHANNEL_OPEN] =		&channel_post_open;
-	channel_post[SSH_CHANNEL_CONNECTING] =		&channel_post_connecting;
-	channel_post[SSH_CHANNEL_DYNAMIC] =		&channel_post_open;
-}
-
-static void
-channel_handler_init(void)
-{
-	int i;
-
-	for (i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
-		channel_pre[i] = NULL;
-		channel_post[i] = NULL;
-	}
-	if (compat20)
-		channel_handler_init_20();
-	else if (compat13)
-		channel_handler_init_13();
-	else
-		channel_handler_init_15();
-}
-
-/* gc dead channels */
-static void
-channel_garbage_collect(Channel *c)
-{
-	if (c == NULL)
-		return;
-	if (c->detach_user != NULL) {
-		if (!chan_is_dead(c, 0))
-			return;
-		debug("channel %d: gc: notify user", c->self);
-		c->detach_user(c->self, NULL);
-		/* if we still have a callback */
-		if (c->detach_user != NULL)
-			return;
-		debug("channel %d: gc: user detached", c->self);
-	}
-	if (!c->wait_for_exit && !chan_is_dead(c, 1))
-		return;
-	debug("channel %d: garbage collecting", c->self);
-	channel_free(c);
-}
-
-static void
-channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
-{
-	static int did_init = 0;
-	int i, oalloc;
-	Channel *c;
-
-	if (!did_init) {
-		channel_handler_init();
-		did_init = 1;
-	}
-	for (i = 0, oalloc = channels_alloc; i < oalloc; i++) {
-		c = channels[i];
-		if (c == NULL)
-			continue;
-		if (c->delayed) {
-			if (ftab == channel_pre)
-				c->delayed = 0;
-			else
-				continue;
-		}
-		if (ftab[c->type] != NULL)
-			(*ftab[c->type])(c, readset, writeset);
-		channel_garbage_collect(c);
-	}
-}
-
-/*
- * Allocate/update select bitmasks and add any bits relevant to channels in
- * select bitmasks.
- */
-void
-channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
-    int *nallocp, int rekeying)
-{
-	int n;
-	u_int sz;
-
-	n = MAX(*maxfdp, channel_max_fd);
-
-	sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
-	/* perhaps check sz < nalloc/2 and shrink? */
-	if (*readsetp == NULL || sz > *nallocp) {
-		*readsetp = xrealloc(*readsetp, sz);
-		*writesetp = xrealloc(*writesetp, sz);
-		*nallocp = sz;
-	}
-	*maxfdp = n;
-	memset(*readsetp, 0, sz);
-	memset(*writesetp, 0, sz);
-
-	if (!rekeying)
-		channel_handler(channel_pre, *readsetp, *writesetp);
-}
-
-/*
- * After select, perform any appropriate operations for channels which have
- * events pending.
- */
-void
-channel_after_select(fd_set * readset, fd_set * writeset)
-{
-	channel_handler(channel_post, readset, writeset);
-}
-
-
-/* If there is data to send to the connection, enqueue some of it now. */
-
-void
-channel_output_poll(void)
-{
-	Channel *c;
-	int i;
-	u_int len;
-
-	for (i = 0; i < channels_alloc; i++) {
-		c = channels[i];
-		if (c == NULL)
-			continue;
-
-		/*
-		 * We are only interested in channels that can have buffered
-		 * incoming data.
-		 */
-		if (compat13) {
-			if (c->type != SSH_CHANNEL_OPEN &&
-			    c->type != SSH_CHANNEL_INPUT_DRAINING)
-				continue;
-		} else {
-			if (c->type != SSH_CHANNEL_OPEN)
-				continue;
-		}
-		if (compat20 &&
-		    (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
-			/* XXX is this true? */
-			debug3("channel %d: will not send data after close", c->self);
-			continue;
-		}
-
-		/* Get the amount of buffered data for this channel. */
-		if ((c->istate == CHAN_INPUT_OPEN ||
-		    c->istate == CHAN_INPUT_WAIT_DRAIN) &&
-		    (len = buffer_len(&c->input)) > 0) {
-			/*
-			 * Send some data for the other side over the secure
-			 * connection.
-			 */
-			if (compat20) {
-				if (len > c->remote_window)
-					len = c->remote_window;
-				if (len > c->remote_maxpacket)
-					len = c->remote_maxpacket;
-			} else {
-				if (packet_is_interactive()) {
-					if (len > 1024)
-						len = 512;
-				} else {
-					/* Keep the packets at reasonable size. */
-					if (len > packet_get_maxsize()/2)
-						len = packet_get_maxsize()/2;
-				}
-			}
-			if (len > 0) {
-				packet_start(compat20 ?
-				    SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
-				packet_put_int(c->remote_id);
-				packet_put_string(buffer_ptr(&c->input), len);
-				packet_send();
-				buffer_consume(&c->input, len);
-				c->remote_window -= len;
-			}
-		} else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
-			if (compat13)
-				fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
-			/*
-			 * input-buffer is empty and read-socket shutdown:
-			 * tell peer, that we will not send more data: send IEOF.
-			 * hack for extended data: delay EOF if EFD still in use.
-			 */
-			if (CHANNEL_EFD_INPUT_ACTIVE(c))
-			       debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
-				   c->self, c->efd, buffer_len(&c->extended));
-			else
-				chan_ibuf_empty(c);
-		}
-		/* Send extended data, i.e. stderr */
-		if (compat20 &&
-		    !(c->flags & CHAN_EOF_SENT) &&
-		    c->remote_window > 0 &&
-		    (len = buffer_len(&c->extended)) > 0 &&
-		    c->extended_usage == CHAN_EXTENDED_READ) {
-			debug2("channel %d: rwin %u elen %u euse %d",
-			    c->self, c->remote_window, buffer_len(&c->extended),
-			    c->extended_usage);
-			if (len > c->remote_window)
-				len = c->remote_window;
-			if (len > c->remote_maxpacket)
-				len = c->remote_maxpacket;
-			packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
-			packet_put_int(c->remote_id);
-			packet_put_int(SSH2_EXTENDED_DATA_STDERR);
-			packet_put_string(buffer_ptr(&c->extended), len);
-			packet_send();
-			buffer_consume(&c->extended, len);
-			c->remote_window -= len;
-			debug2("channel %d: sent ext data %d", c->self, len);
-		}
-	}
-}
-
-
-/* -- protocol input */
-
-void
-channel_input_data(int type, u_int32_t seq, void *ctxt)
-{
-	int id;
-	char *data;
-	u_int data_len;
-	Channel *c;
-
-	/* Get the channel number and verify it. */
-	id = packet_get_int();
-	c = channel_lookup(id);
-	if (c == NULL)
-		packet_disconnect("Received data for nonexistent channel %d.", id);
-
-	/* Ignore any data for non-open channels (might happen on close) */
-	if (c->type != SSH_CHANNEL_OPEN &&
-	    c->type != SSH_CHANNEL_X11_OPEN)
-		return;
-
-	/* same for protocol 1.5 if output end is no longer open */
-	if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
-		return;
-
-	/* Get the data. */
-	data = packet_get_string(&data_len);
-
-	if (compat20) {
-		if (data_len > c->local_maxpacket) {
-			log("channel %d: rcvd big packet %d, maxpack %d",
-			    c->self, data_len, c->local_maxpacket);
-		}
-		if (data_len > c->local_window) {
-			log("channel %d: rcvd too much data %d, win %d",
-			    c->self, data_len, c->local_window);
-			xfree(data);
-			return;
-		}
-		c->local_window -= data_len;
-	}
-	packet_check_eom();
-	buffer_append(&c->output, data, data_len);
-	xfree(data);
-}
-
-void
-channel_input_extended_data(int type, u_int32_t seq, void *ctxt)
-{
-	int id;
-	char *data;
-	u_int data_len, tcode;
-	Channel *c;
-
-	/* Get the channel number and verify it. */
-	id = packet_get_int();
-	c = channel_lookup(id);
-
-	if (c == NULL)
-		packet_disconnect("Received extended_data for bad channel %d.", id);
-	if (c->type != SSH_CHANNEL_OPEN) {
-		log("channel %d: ext data for non open", id);
-		return;
-	}
-	if (c->flags & CHAN_EOF_RCVD) {
-		if (datafellows & SSH_BUG_EXTEOF)
-			debug("channel %d: accepting ext data after eof", id);
-		else
-			packet_disconnect("Received extended_data after EOF "
-			    "on channel %d.", id);
-	}
-	tcode = packet_get_int();
-	if (c->efd == -1 ||
-	    c->extended_usage != CHAN_EXTENDED_WRITE ||
-	    tcode != SSH2_EXTENDED_DATA_STDERR) {
-		log("channel %d: bad ext data", c->self);
-		return;
-	}
-	data = packet_get_string(&data_len);
-	packet_check_eom();
-	if (data_len > c->local_window) {
-		log("channel %d: rcvd too much extended_data %d, win %d",
-		    c->self, data_len, c->local_window);
-		xfree(data);
-		return;
-	}
-	debug2("channel %d: rcvd ext data %d", c->self, data_len);
-	c->local_window -= data_len;
-	buffer_append(&c->extended, data, data_len);
-	xfree(data);
-}
-
-void
-channel_input_ieof(int type, u_int32_t seq, void *ctxt)
-{
-	int id;
-	Channel *c;
-
-	id = packet_get_int();
-	packet_check_eom();
-	c = channel_lookup(id);
-	if (c == NULL)
-		packet_disconnect("Received ieof for nonexistent channel %d.", id);
-	chan_rcvd_ieof(c);
-
-	/* XXX force input close */
-	if (c->force_drain && c->istate == CHAN_INPUT_OPEN) {
-		debug("channel %d: FORCE input drain", c->self);
-		c->istate = CHAN_INPUT_WAIT_DRAIN;
-		if (buffer_len(&c->input) == 0)
-			chan_ibuf_empty(c);
-	}
-
-}
-
-void
-channel_input_close(int type, u_int32_t seq, void *ctxt)
-{
-	int id;
-	Channel *c;
-
-	id = packet_get_int();
-	packet_check_eom();
-	c = channel_lookup(id);
-	if (c == NULL)
-		packet_disconnect("Received close for nonexistent channel %d.", id);
-
-	/*
-	 * Send a confirmation that we have closed the channel and no more
-	 * data is coming for it.
-	 */
-	packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
-	packet_put_int(c->remote_id);
-	packet_send();
-
-	/*
-	 * If the channel is in closed state, we have sent a close request,
-	 * and the other side will eventually respond with a confirmation.
-	 * Thus, we cannot free the channel here, because then there would be
-	 * no-one to receive the confirmation.  The channel gets freed when
-	 * the confirmation arrives.
-	 */
-	if (c->type != SSH_CHANNEL_CLOSED) {
-		/*
-		 * Not a closed channel - mark it as draining, which will
-		 * cause it to be freed later.
-		 */
-		buffer_clear(&c->input);
-		c->type = SSH_CHANNEL_OUTPUT_DRAINING;
-	}
-}
-
-/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
-void
-channel_input_oclose(int type, u_int32_t seq, void *ctxt)
-{
-	int id = packet_get_int();
-	Channel *c = channel_lookup(id);
-
-	packet_check_eom();
-	if (c == NULL)
-		packet_disconnect("Received oclose for nonexistent channel %d.", id);
-	chan_rcvd_oclose(c);
-}
-
-void
-channel_input_close_confirmation(int type, u_int32_t seq, void *ctxt)
-{
-	int id = packet_get_int();
-	Channel *c = channel_lookup(id);
-
-	packet_check_eom();
-	if (c == NULL)
-		packet_disconnect("Received close confirmation for "
-		    "out-of-range channel %d.", id);
-	if (c->type != SSH_CHANNEL_CLOSED)
-		packet_disconnect("Received close confirmation for "
-		    "non-closed channel %d (type %d).", id, c->type);
-	channel_free(c);
-}
-
-void
-channel_input_open_confirmation(int type, u_int32_t seq, void *ctxt)
-{
-	int id, remote_id;
-	Channel *c;
-
-	id = packet_get_int();
-	c = channel_lookup(id);
-
-	if (c==NULL || c->type != SSH_CHANNEL_OPENING)
-		packet_disconnect("Received open confirmation for "
-		    "non-opening channel %d.", id);
-	remote_id = packet_get_int();
-	/* Record the remote channel number and mark that the channel is now open. */
-	c->remote_id = remote_id;
-	c->type = SSH_CHANNEL_OPEN;
-
-	if (compat20) {
-		c->remote_window = packet_get_int();
-		c->remote_maxpacket = packet_get_int();
-		if (c->confirm) {
-			debug2("callback start");
-			c->confirm(c->self, NULL);
-			debug2("callback done");
-		}
-		debug("channel %d: open confirm rwindow %u rmax %u", c->self,
-		    c->remote_window, c->remote_maxpacket);
-	}
-	packet_check_eom();
-}
-
-static char *
-reason2txt(int reason)
-{
-	switch (reason) {
-	case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED:
-		return "administratively prohibited";
-	case SSH2_OPEN_CONNECT_FAILED:
-		return "connect failed";
-	case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE:
-		return "unknown channel type";
-	case SSH2_OPEN_RESOURCE_SHORTAGE:
-		return "resource shortage";
-	}
-	return "unknown reason";
-}
-
-void
-channel_input_open_failure(int type, u_int32_t seq, void *ctxt)
-{
-	int id, reason;
-	char *msg = NULL, *lang = NULL;
-	Channel *c;
-
-	id = packet_get_int();
-	c = channel_lookup(id);
-
-	if (c==NULL || c->type != SSH_CHANNEL_OPENING)
-		packet_disconnect("Received open failure for "
-		    "non-opening channel %d.", id);
-	if (compat20) {
-		reason = packet_get_int();
-		if (!(datafellows & SSH_BUG_OPENFAILURE)) {
-			msg  = packet_get_string(NULL);
-			lang = packet_get_string(NULL);
-		}
-		log("channel %d: open failed: %s%s%s", id,
-		    reason2txt(reason), msg ? ": ": "", msg ? msg : "");
-		if (msg != NULL)
-			xfree(msg);
-		if (lang != NULL)
-			xfree(lang);
-	}
-	packet_check_eom();
-	/* Free the channel.  This will also close the socket. */
-	channel_free(c);
-}
-
-void
-channel_input_window_adjust(int type, u_int32_t seq, void *ctxt)
-{
-	Channel *c;
-	int id;
-	u_int adjust;
-
-	if (!compat20)
-		return;
-
-	/* Get the channel number and verify it. */
-	id = packet_get_int();
-	c = channel_lookup(id);
-
-	if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
-		log("Received window adjust for "
-		    "non-open channel %d.", id);
-		return;
-	}
-	adjust = packet_get_int();
-	packet_check_eom();
-	debug2("channel %d: rcvd adjust %u", id, adjust);
-	c->remote_window += adjust;
-}
-
-void
-channel_input_port_open(int type, u_int32_t seq, void *ctxt)
-{
-	Channel *c = NULL;
-	u_short host_port;
-	char *host, *originator_string;
-	int remote_id, sock = -1;
-
-	remote_id = packet_get_int();
-	host = packet_get_string(NULL);
-	host_port = packet_get_int();
-
-	if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
-		originator_string = packet_get_string(NULL);
-	} else {
-		originator_string = xstrdup("unknown (remote did not supply name)");
-	}
-	packet_check_eom();
-	sock = channel_connect_to(host, host_port);
-	if (sock != -1) {
-		c = channel_new("connected socket",
-		    SSH_CHANNEL_CONNECTING, sock, sock, -1, 0, 0, 0,
-		    originator_string, 1);
-		c->remote_id = remote_id;
-	}
-	if (c == NULL) {
-		packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
-		packet_put_int(remote_id);
-		packet_send();
-	}
-	xfree(host);
-}
-
-
-/* -- tcp forwarding */
-
-void
-channel_set_af(int af)
-{
-	IPv4or6 = af;
-}
-
-static int
-channel_setup_fwd_listener(int type, const char *listen_addr, u_short listen_port,
-    const char *host_to_connect, u_short port_to_connect, int gateway_ports)
-{
-	Channel *c;
-	int sock, r, is_client, on = 1, wildcard = 0, success = 0;
-	struct addrinfo hints, *ai, *aitop;
-	const char *host, *addr;
-	char ntop[NI_MAXHOST], strport[NI_MAXSERV];
-
-	host = (type == SSH_CHANNEL_RPORT_LISTENER) ?
-	    listen_addr : host_to_connect;
-	is_client = (type == SSH_CHANNEL_PORT_LISTENER);
-
-	if (host == NULL) {
-		error("No forward host name.");
-		return 0;
-	}
-	if (strlen(host) > SSH_CHANNEL_PATH_LEN - 1) {
-		error("Forward host name too long.");
-		return 0;
-	}
-
-	/*
-	 * Determine whether or not a port forward listens to loopback,
-	 * specified address or wildcard. On the client, a specified bind
-	 * address will always override gateway_ports. On the server, a
-	 * gateway_ports of 1 (``yes'') will override the client's
-	 * specification and force a wildcard bind, whereas a value of 2
-	 * (``clientspecified'') will bind to whatever address the client
-	 * asked for.
-	 *
-	 * Special-case listen_addrs are:
-	 *
-	 * "0.0.0.0"               -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
-	 * "" (empty string), "*"  -> wildcard v4/v6
-	 * "localhost"             -> loopback v4/v6
-	 */
-	addr = NULL;
-	if (listen_addr == NULL) {
-		/* No address specified: default to gateway_ports setting */
-		if (gateway_ports)
-			wildcard = 1;
-	} else if (gateway_ports || is_client) {
-		if (((datafellows & SSH_OLD_FORWARD_ADDR) &&
-		    strcmp(listen_addr, "0.0.0.0") == 0 && is_client == 0) ||
-		    *listen_addr == '\0' || strcmp(listen_addr, "*") == 0 ||
-		    (!is_client && gateway_ports == 1))
-			wildcard = 1;
-		else if (strcmp(listen_addr, "localhost") != 0)
-			addr = listen_addr;
-	}
-
-	debug3("channel_setup_fwd_listener: type %d wildcard %d addr %s",
-	    type, wildcard, (addr == NULL) ? "NULL" : addr);
-
-	/*
-	 * getaddrinfo returns a loopback address if the hostname is
-	 * set to NULL and hints.ai_flags is not AI_PASSIVE
-	 */
-	memset(&hints, 0, sizeof(hints));
-	hints.ai_family = IPv4or6;
-	hints.ai_flags = wildcard ? AI_PASSIVE : 0;
-	hints.ai_socktype = SOCK_STREAM;
-	snprintf(strport, sizeof strport, "%d", listen_port);
-	if ((r = getaddrinfo(addr, strport, &hints, &aitop)) != 0) {
-		if (addr == NULL) {
-			/* This really shouldn't happen */
-			packet_disconnect("getaddrinfo: fatal error: %s",
-			    gai_strerror(r));
-		} else {
-			error("channel_setup_fwd_listener: "
-			    "getaddrinfo(%.64s): %s", addr, gai_strerror(r));
-		}
-		return 0;
-	}
-
-	for (ai = aitop; ai; ai = ai->ai_next) {
-		if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
-			continue;
-		if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
-		    strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
-			error("channel_setup_fwd_listener: getnameinfo failed");
-			continue;
-		}
-		/* Create a port to listen for the host. */
-		sock = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
-		if (sock < 0) {
-			/* this is no error since kernel may not support ipv6 */
-			verbose("socket: %.100s", strerror(errno));
-			continue;
-		}
-		/*
-		 * Set socket options.
-		 * Allow local port reuse in TIME_WAIT.
-		 */
-		if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &on,
-		    sizeof(on)) == -1)
-			error("setsockopt SO_REUSEADDR: %s", strerror(errno));
-
-		debug("Local forwarding listening on %s port %s.", ntop, strport);
-
-		/* Bind the socket to the address. */
-		if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
-			/* address can be in use ipv6 address is already bound */
-			if (!ai->ai_next)
-				error("bind: %.100s", strerror(errno));
-			else
-				verbose("bind: %.100s", strerror(errno));
-
-			close(sock);
-			continue;
-		}
-		/* Start listening for connections on the socket. */
-		if (listen(sock, 5) < 0) {
-			error("listen: %.100s", strerror(errno));
-			close(sock);
-			continue;
-		}
-		/* Allocate a channel number for the socket. */
-		c = channel_new("port listener", type, sock, sock, -1,
-		    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
-		    0, xstrdup("port listener"), 1);
-		strlcpy(c->path, host, sizeof(c->path));
-		c->host_port = port_to_connect;
-		c->listening_port = listen_port;
-		success = 1;
-	}
-	if (success == 0)
-		error("channel_setup_fwd_listener: cannot listen to port: %d",
-		    listen_port);
-	freeaddrinfo(aitop);
-	return success;
-}
-
-int
-channel_cancel_rport_listener(const char *host, u_short port)
-{
-	u_int i;
-	int found = 0;
-
-	for (i = 0; i < channels_alloc; i++) {
-		Channel *c = channels[i];
-
-		if (c != NULL && c->type == SSH_CHANNEL_RPORT_LISTENER &&
-		    strncmp(c->path, host, sizeof(c->path)) == 0 &&
-		    c->listening_port == port) {
-			debug2("%s: close channel %d", __func__, i);
-			channel_free(c);
-			found = 1;
-		}
-	}
-
-	return (found);
-}
-
-/* protocol local port fwd, used by ssh (and sshd in v1) */
-int
-channel_setup_local_fwd_listener(const char *listen_host, u_short listen_port,
-    const char *host_to_connect, u_short port_to_connect, int gateway_ports)
-{
-	return channel_setup_fwd_listener(SSH_CHANNEL_PORT_LISTENER,
-	    listen_host, listen_port, host_to_connect, port_to_connect,
-	    gateway_ports);
-}
-
-/* protocol v2 remote port fwd, used by sshd */
-int
-channel_setup_remote_fwd_listener(const char *listen_address,
-    u_short listen_port, int gateway_ports)
-{
-	return channel_setup_fwd_listener(SSH_CHANNEL_RPORT_LISTENER,
-	    listen_address, listen_port, NULL, 0, gateway_ports);
-}
-
-/*
- * Initiate forwarding of connections to port "port" on remote host through
- * the secure channel to host:port from local side.
- */
-
-int
-channel_request_remote_forwarding(const char *listen_host, u_short listen_port,
-    const char *host_to_connect, u_short port_to_connect)
-{
-	int type, success = 0;
-
-	/* Record locally that connection to this host/port is permitted. */
-	if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
-		fatal("channel_request_remote_forwarding: too many forwards");
-
-	if (listen_host != NULL &&
-	    strlen(listen_host) > SSH_CHANNEL_PATH_LEN - 1) {
-		error("Binding address too long.");
-		return -1;
-	}
-
-	/* Send the forward request to the remote side. */
-	if (compat20) {
-		const char *address_to_bind;
-		if (listen_host == NULL) {
-			if (datafellows & SSH_BUG_RFWD_ADDR)
-				address_to_bind = "127.0.0.1";
-			else
-				address_to_bind = "localhost";
-		} else if (*listen_host == '\0' ||
-			   strcmp(listen_host, "*") == 0) {
-			if (datafellows & SSH_BUG_RFWD_ADDR)
-				address_to_bind = "0.0.0.0";
-			else
-				address_to_bind = "";
-		} else
-			address_to_bind = listen_host;
-
-		packet_start(SSH2_MSG_GLOBAL_REQUEST);
-		packet_put_cstring("tcpip-forward");
-		packet_put_char(1);			/* boolean: want reply */
-		packet_put_cstring(address_to_bind);
-		packet_put_int(listen_port);
-		packet_send();
-		packet_write_wait();
-		/* Assume that server accepts the request */
-		success = 1;
-	} else {
-		packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
-		packet_put_int(listen_port);
-		packet_put_cstring(host_to_connect);
-		packet_put_int(port_to_connect);
-		packet_send();
-		packet_write_wait();
-
-		/* Wait for response from the remote side. */
-		type = packet_read();
-		switch (type) {
-		case SSH_SMSG_SUCCESS:
-			success = 1;
-			break;
-		case SSH_SMSG_FAILURE:
-			log("Warning: Server denied remote port forwarding.");
-			break;
-		default:
-			/* Unknown packet */
-			packet_disconnect("Protocol error for port forward request:"
-			    "received packet type %d.", type);
-		}
-	}
-	if (success) {
-		permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
-		permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
-		permitted_opens[num_permitted_opens].listen_port = listen_port;
-		num_permitted_opens++;
-	}
-	return (success ? 0 : -1);
-}
-
-/*
- * Request cancellation of remote forwarding of connection host:port from
- * local side.
- */
-void
-channel_request_rforward_cancel(const char *host, u_short port)
-{
-	int i;
-
-	if (!compat20)
-		return;
-
-	for (i = 0; i < num_permitted_opens; i++) {
-		if (permitted_opens[i].host_to_connect != NULL &&
-		    permitted_opens[i].listen_port == port)
-			break;
-	}
-	if (i >= num_permitted_opens) {
-		debug("%s: requested forward not found", __func__);
-		return;
-	}
-	packet_start(SSH2_MSG_GLOBAL_REQUEST);
-	packet_put_cstring("cancel-tcpip-forward");
-	packet_put_char(0);
-	packet_put_cstring(host == NULL ? "" : host);
-	packet_put_int(port);
-	packet_send();
-
-	permitted_opens[i].listen_port = 0;
-	permitted_opens[i].port_to_connect = 0;
-	xfree(permitted_opens[i].host_to_connect);
-	permitted_opens[i].host_to_connect = NULL;
-}
-
-/*
- * This is called after receiving CHANNEL_FORWARDING_REQUEST.  This initates
- * listening for the port, and sends back a success reply (or disconnect
- * message if there was an error).  This never returns if there was an error.
- */
-
-void
-channel_input_port_forward_request(int is_root, int gateway_ports)
-{
-	u_short port, host_port;
-	char *hostname;
-
-	/* Get arguments from the packet. */
-	port = packet_get_int();
-	hostname = packet_get_string(NULL);
-	host_port = packet_get_int();
-
-#ifndef HAVE_CYGWIN
-	/*
-	 * Check that an unprivileged user is not trying to forward a
-	 * privileged port.
-	 */
-	if (port < IPPORT_RESERVED && !is_root)
-		packet_disconnect("Requested forwarding of port %d but user is not root.",
-				  port);
-#endif
-	/* Initiate forwarding */
-	channel_setup_local_fwd_listener(NULL, port, hostname,
-	    host_port, gateway_ports);
-
-	/* Free the argument string. */
-	xfree(hostname);
-}
-
-/*
- * Permits opening to any host/port if permitted_opens[] is empty.  This is
- * usually called by the server, because the user could connect to any port
- * anyway, and the server has no way to know but to trust the client anyway.
- */
-void
-channel_permit_all_opens(void)
-{
-	if (num_permitted_opens == 0)
-		all_opens_permitted = 1;
-}
-
-void
-channel_add_permitted_opens(char *host, int port)
-{
-	if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
-		fatal("channel_add_permitted_opens: too many forwards");
-	debug("allow port forwarding to host %s port %d", host, port);
-
-	permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
-	permitted_opens[num_permitted_opens].port_to_connect = port;
-	num_permitted_opens++;
-
-	all_opens_permitted = 0;
-}
-
-void
-channel_clear_permitted_opens(void)
-{
-	int i;
-
-	for (i = 0; i < num_permitted_opens; i++)
-		xfree(permitted_opens[i].host_to_connect);
-	num_permitted_opens = 0;
-}
-
-
-/* return socket to remote host, port */
-static int
-connect_to(const char *host, u_short port)
-{
-	struct addrinfo hints, *ai, *aitop;
-	char ntop[NI_MAXHOST], strport[NI_MAXSERV];
-	int gaierr;
-	int sock = -1;
-
-	memset(&hints, 0, sizeof(hints));
-	hints.ai_family = IPv4or6;
-	hints.ai_socktype = SOCK_STREAM;
-	snprintf(strport, sizeof strport, "%d", port);
-	if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
-		error("connect_to %.100s: unknown host (%s)", host,
-		    gai_strerror(gaierr));
-		return -1;
-	}
-	for (ai = aitop; ai; ai = ai->ai_next) {
-		if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
-			continue;
-		if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
-		    strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
-			error("connect_to: getnameinfo failed");
-			continue;
-		}
-		sock = socket(ai->ai_family, SOCK_STREAM, 0);
-		if (sock < 0) {
-			error("socket: %.100s", strerror(errno));
-			continue;
-		}
-		if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
-			fatal("connect_to: F_SETFL: %s", strerror(errno));
-		if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
-		    errno != EINPROGRESS) {
-			error("connect_to %.100s port %s: %.100s", ntop, strport,
-			    strerror(errno));
-			close(sock);
-			continue;	/* fail -- try next */
-		}
-		break; /* success */
-
-	}
-	freeaddrinfo(aitop);
-	if (!ai) {
-		error("connect_to %.100s port %d: failed.", host, port);
-		return -1;
-	}
-	/* success */
-	set_nodelay(sock);
-	return sock;
-}
-
-int
-channel_connect_by_listen_address(u_short listen_port)
-{
-	int i;
-
-	for (i = 0; i < num_permitted_opens; i++)
-		if (permitted_opens[i].listen_port == listen_port)
-			return connect_to(
-			    permitted_opens[i].host_to_connect,
-			    permitted_opens[i].port_to_connect);
-	error("WARNING: Server requests forwarding for unknown listen_port %d",
-	    listen_port);
-	return -1;
-}
-
-/* Check if connecting to that port is permitted and connect. */
-int
-channel_connect_to(const char *host, u_short port)
-{
-	int i, permit;
-
-	permit = all_opens_permitted;
-	if (!permit) {
-		for (i = 0; i < num_permitted_opens; i++)
-			if (permitted_opens[i].port_to_connect == port &&
-			    strcmp(permitted_opens[i].host_to_connect, host) == 0)
-				permit = 1;
-
-	}
-	if (!permit) {
-		log("Received request to connect to host %.100s port %d, "
-		    "but the request was denied.", host, port);
-		return -1;
-	}
-	return connect_to(host, port);
-}
-
-/* -- X11 forwarding */
-
-/*
- * Creates an internet domain socket for listening for X11 connections.
- * Returns 0 and a suitable display number for the DISPLAY variable
- * stored in display_numberp , or -1 if an error occurs.
- */
-int
-x11_create_display_inet(int x11_display_offset, int x11_use_localhost,
-    int single_connection, u_int *display_numberp)
-{
-	Channel *nc = NULL;
-	int display_number, sock;
-	u_short port;
-	struct addrinfo hints, *ai, *aitop;
-	char strport[NI_MAXSERV];
-	int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
-
-	for (display_number = x11_display_offset;
-	    display_number < MAX_DISPLAYS;
-	    display_number++) {
-		port = 6000 + display_number;
-		memset(&hints, 0, sizeof(hints));
-		hints.ai_family = IPv4or6;
-		hints.ai_flags = x11_use_localhost ? 0: AI_PASSIVE;
-		hints.ai_socktype = SOCK_STREAM;
-		snprintf(strport, sizeof strport, "%d", port);
-		if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
-			error("getaddrinfo: %.100s", gai_strerror(gaierr));
-			return -1;
-		}
-		for (ai = aitop; ai; ai = ai->ai_next) {
-			if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
-				continue;
-			sock = socket(ai->ai_family, SOCK_STREAM, 0);
-			if (sock < 0) {
-				if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
-					error("socket: %.100s", strerror(errno));
-					freeaddrinfo(aitop);
-					for (n = 0; n < num_socks; n++)
-						close(socks[n]);
-					return -1;
-				} else {
-					debug("x11_create_display_inet: Socket family %d not supported",
-						 ai->ai_family);
-					continue;
-				}
-			}
-#ifdef IPV6_V6ONLY
-			if (ai->ai_family == AF_INET6) {
-				int on = 1;
-				if (setsockopt(sock, IPPROTO_IPV6, IPV6_V6ONLY, &on, sizeof(on)) < 0)
-					error("setsockopt IPV6_V6ONLY: %.100s", strerror(errno));
-			}
-#endif
-			if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
-				/*
-				 * If bind() fails  with EADDRNOTAVAIL, we
-				 * should not break immediately but rather
-				 * try the next address available.
-				 */
-				if (errno == EADDRNOTAVAIL) {
-					close(sock);
-					continue;
-				}
-								
-				debug("bind port %d: %.100s; skipping this port", port,
-				    strerror(errno));
-				close(sock);
-
-				for (n = 0; n < num_socks; n++) {
-					close(socks[n]);
-				}
-				num_socks = 0;
-				break;
-			}
-			socks[num_socks++] = sock;
-#ifndef DONT_TRY_OTHER_AF
-			if (num_socks == NUM_SOCKS)
-				break;
-#else
-			if (x11_use_localhost) {
-				if (num_socks == NUM_SOCKS)
-					break;
-			} else {
-				break;
-			}
-#endif
-		}
-		freeaddrinfo(aitop);
-		if (num_socks > 0)
-			break;
-	}
-	if (display_number >= MAX_DISPLAYS) {
-		error("Failed to allocate internet-domain X11 display socket.");
-		return -1;
-	}
-	/* Start listening for connections on the socket. */
-	for (n = 0; n < num_socks; n++) {
-		sock = socks[n];
-		if (listen(sock, 5) < 0) {
-			int i;
-			error("listen: %.100s", strerror(errno));
-			for (i = 0; i < num_socks; i++)
-				close(socks[i]);
-			return -1;
-		}
-	}
-
-	/* Allocate a channel for each socket. */
-	for (n = 0; n < num_socks; n++) {
-		sock = socks[n];
-		nc = channel_new("x11 listener",
-		    SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
-		    CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
-		    0, xstrdup("X11 inet listener"), 1);
-		nc->single_connection = single_connection;
-	}
-
-	/* Return the display number for the DISPLAY environment variable. */
-	*display_numberp = display_number;
-	return (0);
-}
-
-static int
-connect_local_xsocket(u_int dnr)
-{
-	int sock;
-	struct sockaddr_un addr;
-
-	sock = socket(AF_UNIX, SOCK_STREAM, 0);
-	if (sock < 0)
-		error("socket: %.100s", strerror(errno));
-	memset(&addr, 0, sizeof(addr));
-	addr.sun_family = AF_UNIX;
-	snprintf(addr.sun_path, sizeof addr.sun_path, _PATH_UNIX_X, dnr);
-	if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
-		return sock;
-	close(sock);
-	error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
-	return -1;
-}
-
-int
-x11_connect_display(void)
-{
-	int display_number, sock = 0;
-	const char *display;
-	char buf[1024], *cp;
-	struct addrinfo hints, *ai, *aitop;
-	char strport[NI_MAXSERV];
-	int gaierr;
-
-	/* Try to open a socket for the local X server. */
-	display = getenv("DISPLAY");
-	if (!display) {
-		error("DISPLAY not set.");
-		return -1;
-	}
-	/*
-	 * Now we decode the value of the DISPLAY variable and make a
-	 * connection to the real X server.
-	 */
-
-	/*
-	 * Check if it is a unix domain socket.  Unix domain displays are in
-	 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
-	 */
-	if (strncmp(display, "unix:", 5) == 0 ||
-	    display[0] == ':') {
-		/* Connect to the unix domain socket. */
-		if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
-			error("Could not parse display number from DISPLAY: %.100s",
-			    display);
-			return -1;
-		}
-		/* Create a socket. */
-		sock = connect_local_xsocket(display_number);
-		if (sock < 0)
-			return -1;
-
-		/* OK, we now have a connection to the display. */
-		return sock;
-	}
-	/*
-	 * Connect to an inet socket.  The DISPLAY value is supposedly
-	 * hostname:d[.s], where hostname may also be numeric IP address.
-	 */
-	strlcpy(buf, display, sizeof(buf));
-	cp = strchr(buf, ':');
-	if (!cp) {
-		error("Could not find ':' in DISPLAY: %.100s", display);
-		return -1;
-	}
-	*cp = 0;
-	/* buf now contains the host name.  But first we parse the display number. */
-	if (sscanf(cp + 1, "%d", &display_number) != 1) {
-		error("Could not parse display number from DISPLAY: %.100s",
-		    display);
-		return -1;
-	}
-
-	/* Look up the host address */
-	memset(&hints, 0, sizeof(hints));
-	hints.ai_family = IPv4or6;
-	hints.ai_socktype = SOCK_STREAM;
-	snprintf(strport, sizeof strport, "%d", 6000 + display_number);
-	if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
-		error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
-		return -1;
-	}
-	for (ai = aitop; ai; ai = ai->ai_next) {
-		/* Create a socket. */
-		sock = socket(ai->ai_family, SOCK_STREAM, 0);
-		if (sock < 0) {
-			debug("socket: %.100s", strerror(errno));
-			continue;
-		}
-		/* Connect it to the display. */
-		if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
-			debug("connect %.100s port %d: %.100s", buf,
-			    6000 + display_number, strerror(errno));
-			close(sock);
-			continue;
-		}
-		/* Success */
-		break;
-	}
-	freeaddrinfo(aitop);
-	if (!ai) {
-		error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
-		    strerror(errno));
-		return -1;
-	}
-	set_nodelay(sock);
-	return sock;
-}
-
-/*
- * This is called when SSH_SMSG_X11_OPEN is received.  The packet contains
- * the remote channel number.  We should do whatever we want, and respond
- * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
- */
-
-void
-x11_input_open(int type, u_int32_t seq, void *ctxt)
-{
-	Channel *c = NULL;
-	int remote_id, sock = 0;
-	char *remote_host;
-
-	debug("Received X11 open request.");
-
-	remote_id = packet_get_int();
-
-	if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN) {
-		remote_host = packet_get_string(NULL);
-	} else {
-		remote_host = xstrdup("unknown (remote did not supply name)");
-	}
-	packet_check_eom();
-
-	/* Obtain a connection to the real X display. */
-	sock = x11_connect_display();
-	if (sock != -1) {
-		/* Allocate a channel for this connection. */
-		c = channel_new("connected x11 socket",
-		    SSH_CHANNEL_X11_OPEN, sock, sock, -1, 0, 0, 0,
-		    remote_host, 1);
-		c->remote_id = remote_id;
-		c->force_drain = 1;
-	}
-	if (c == NULL) {
-		/* Send refusal to the remote host. */
-		packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
-		packet_put_int(remote_id);
-	} else {
-		/* Send a confirmation to the remote host. */
-		packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
-		packet_put_int(remote_id);
-		packet_put_int(c->self);
-	}
-	packet_send();
-}
-
-/* dummy protocol handler that denies SSH-1 requests (agent/x11) */
-void
-deny_input_open(int type, u_int32_t seq, void *ctxt)
-{
-	int rchan = packet_get_int();
-
-	switch (type) {
-	case SSH_SMSG_AGENT_OPEN:
-		error("Warning: ssh server tried agent forwarding.");
-		break;
-	case SSH_SMSG_X11_OPEN:
-		error("Warning: ssh server tried X11 forwarding.");
-		break;
-	default:
-		error("deny_input_open: type %d", type);
-		break;
-	}
-	error("Warning: this is probably a break in attempt by a malicious server.");
-	packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
-	packet_put_int(rchan);
-	packet_send();
-}
-
-/*
- * Requests forwarding of X11 connections, generates fake authentication
- * data, and enables authentication spoofing.
- * This should be called in the client only.
- */
-void
-x11_request_forwarding_with_spoofing(int client_session_id, const char *disp,
-    const char *proto, const char *data)
-{
-	u_int data_len = (u_int) strlen(data) / 2;
-	u_int i, value;
-	char *new_data;
-	int screen_number;
-	const char *cp;
-	u_int32_t rand = 0;
-
-	cp = disp;
-	if (disp)
-		cp = strchr(disp, ':');
-	if (cp)
-		cp = strchr(cp, '.');
-	if (cp)
-		screen_number = atoi(cp + 1);
-	else
-		screen_number = 0;
-
-	/* Save protocol name. */
-	x11_saved_proto = xstrdup(proto);
-
-	/*
-	 * Extract real authentication data and generate fake data of the
-	 * same length.
-	 */
-	x11_saved_data = xmalloc(data_len);
-	x11_fake_data = xmalloc(data_len);
-	for (i = 0; i < data_len; i++) {
-		if (sscanf(data + 2 * i, "%2x", &value) != 1)
-			fatal("x11_request_forwarding: bad authentication data: %.100s", data);
-		if (i % 4 == 0)
-			rand = arc4random();
-		x11_saved_data[i] = value;
-		x11_fake_data[i] = rand & 0xff;
-		rand >>= 8;
-	}
-	x11_saved_data_len = data_len;
-	x11_fake_data_len = data_len;
-
-	/* Convert the fake data into hex. */
-	new_data = tohex(x11_fake_data, data_len);
-
-	/* Send the request packet. */
-	if (compat20) {
-		channel_request_start(client_session_id, "x11-req", 0);
-		packet_put_char(0);	/* XXX bool single connection */
-	} else {
-		packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
-	}
-	packet_put_cstring(proto);
-	packet_put_cstring(new_data);
-	packet_put_int(screen_number);
-	packet_send();
-	packet_write_wait();
-	xfree(new_data);
-}
-
-
-/* -- agent forwarding */
-
-/* Sends a message to the server to request authentication fd forwarding. */
-
-void
-auth_request_forwarding(void)
-{
-	packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
-	packet_send();
-	packet_write_wait();
-}
-
-/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
-
-void
-auth_input_open_request(int type, u_int32_t seq, void *ctxt)
-{
-	Channel *c = NULL;
-	int remote_id, sock;
-	char *name;
-
-	/* Read the remote channel number from the message. */
-	remote_id = packet_get_int();
-	packet_check_eom();
-
-	/*
-	 * Get a connection to the local authentication agent (this may again
-	 * get forwarded).
-	 */
-	sock = ssh_get_authentication_socket();
-
-	/*
-	 * If we could not connect the agent, send an error message back to
-	 * the server. This should never happen unless the agent dies,
-	 * because authentication forwarding is only enabled if we have an
-	 * agent.
-	 */
-	if (sock >= 0) {
-		name = xstrdup("authentication agent connection");
-		c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
-		    -1, 0, 0, 0, name, 1);
-		c->remote_id = remote_id;
-		c->force_drain = 1;
-	}
-	if (c == NULL) {
-		packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
-		packet_put_int(remote_id);
-	} else {
-		/* Send a confirmation to the remote host. */
-		debug("Forwarding authentication connection.");
-		packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
-		packet_put_int(remote_id);
-		packet_put_int(c->self);
-	}
-	packet_send();
-}
