tidy up session multiplexing code, moving it into its own file and

making the function names more consistent - making ssh.c and
clientloop.c a fair bit more readable.

ok markus@

5 files changed, 692 insertions, 598 deletions

diff --git a/usr.bin/ssh/clientloop.c b/usr.bin/ssh/clientloop.c
index 91244d10a72..49177709014 100644
--- a/usr.bin/ssh/clientloop.c
+++ b/usr.bin/ssh/clientloop.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.c,v 1.191 2008/05/09 04:55:56 djm Exp $ */
+/* $OpenBSD: clientloop.c,v 1.192 2008/05/09 14:18:44 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -113,7 +113,7 @@ extern int stdin_null_flag;
 extern int no_shell_flag;
 
 /* Control socket */
-extern int control_fd;
+extern int muxserver_sock;
 
 /*
  * Name of the host we are connecting to.  This is the name given on the
@@ -154,17 +154,6 @@ static int session_closed = 0;	/* In SSH2: login session closed. */
 static void client_init_dispatch(void);
 int	session_ident = -1;
 
-struct confirm_ctx {
-	int want_tty;
-	int want_subsys;
-	int want_x_fwd;
-	int want_agent_fwd;
-	Buffer cmd;
-	char *term;
-	struct termios tio;
-	char **env;
-};
-
 struct channel_reply_ctx {
 	const char *request_type;
 	int id, do_close;
@@ -530,8 +519,8 @@ client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
 	if (packet_have_data_to_write())
 		FD_SET(connection_out, *writesetp);
 
-	if (control_fd != -1)
-		FD_SET(control_fd, *readsetp);
+	if (muxserver_sock != -1)
+		FD_SET(muxserver_sock, *readsetp);
 
 	/*
 	 * Wait for something to happen.  This will suspend the process until
@@ -699,284 +688,6 @@ client_expect_confirm(int id, const char *request, int do_close)
 }
 
 static void
-client_extra_session2_setup(int id, void *arg)
-{
-	struct confirm_ctx *cctx = arg;
-	const char *display;
-	Channel *c;
-	int i;
-
-	if (cctx == NULL)
-		fatal("%s: cctx == NULL", __func__);
-	if ((c = channel_lookup(id)) == NULL)
-		fatal("%s: no channel for id %d", __func__, id);
-
-	display = getenv("DISPLAY");
-	if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
-		char *proto, *data;
-		/* Get reasonable local authentication information. */
-		client_x11_get_proto(display, options.xauth_location,
-		    options.forward_x11_trusted, &proto, &data);
-		/* Request forwarding with authentication spoofing. */
-		debug("Requesting X11 forwarding with authentication spoofing.");
-		x11_request_forwarding_with_spoofing(id, display, proto, data);
-		/* XXX wait for reply */
-	}
-
-	if (cctx->want_agent_fwd && options.forward_agent) {
-		debug("Requesting authentication agent forwarding.");
-		channel_request_start(id, "auth-agent-req@openssh.com", 0);
-		packet_send();
-	}
-
-	client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
-	    cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env);
-
-	c->open_confirm_ctx = NULL;
-	buffer_free(&cctx->cmd);
-	xfree(cctx->term);
-	if (cctx->env != NULL) {
-		for (i = 0; cctx->env[i] != NULL; i++)
-			xfree(cctx->env[i]);
-		xfree(cctx->env);
-	}
-	xfree(cctx);
-}
-
-static void
-client_process_control(fd_set *readset)
-{
-	Buffer m;
-	Channel *c;
-	int client_fd, new_fd[3], ver, allowed, window, packetmax;
-	socklen_t addrlen;
-	struct sockaddr_storage addr;
-	struct confirm_ctx *cctx;
-	char *cmd;
-	u_int i, j, len, env_len, command, flags;
-	uid_t euid;
-	gid_t egid;
-
-	/*
-	 * Accept connection on control socket
-	 */
-	if (control_fd == -1 || !FD_ISSET(control_fd, readset))
-		return;
-
-	memset(&addr, 0, sizeof(addr));
-	addrlen = sizeof(addr);
-	if ((client_fd = accept(control_fd,
-	    (struct sockaddr*)&addr, &addrlen)) == -1) {
-		error("%s accept: %s", __func__, strerror(errno));
-		return;
-	}
-
-	if (getpeereid(client_fd, &euid, &egid) < 0) {
-		error("%s getpeereid failed: %s", __func__, strerror(errno));
-		close(client_fd);
-		return;
-	}
-	if ((euid != 0) && (getuid() != euid)) {
-		error("control mode uid mismatch: peer euid %u != uid %u",
-		    (u_int) euid, (u_int) getuid());
-		close(client_fd);
-		return;
-	}
-
-	unset_nonblock(client_fd);
-
-	/* Read command */
-	buffer_init(&m);
-	if (ssh_msg_recv(client_fd, &m) == -1) {
-		error("%s: client msg_recv failed", __func__);
-		close(client_fd);
-		buffer_free(&m);
-		return;
-	}
-	if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
-		error("%s: wrong client version %d", __func__, ver);
-		buffer_free(&m);
-		close(client_fd);
-		return;
-	}
-
-	allowed = 1;
-	command = buffer_get_int(&m);
-	flags = buffer_get_int(&m);
-
-	buffer_clear(&m);
-
-	switch (command) {
-	case SSHMUX_COMMAND_OPEN:
-		if (options.control_master == SSHCTL_MASTER_ASK ||
-		    options.control_master == SSHCTL_MASTER_AUTO_ASK)
-			allowed = ask_permission("Allow shared connection "
-			    "to %s? ", host);
-		/* continue below */
-		break;
-	case SSHMUX_COMMAND_TERMINATE:
-		if (options.control_master == SSHCTL_MASTER_ASK ||
-		    options.control_master == SSHCTL_MASTER_AUTO_ASK)
-			allowed = ask_permission("Terminate shared connection "
-			    "to %s? ", host);
-		if (allowed)
-			quit_pending = 1;
-		/* FALLTHROUGH */
-	case SSHMUX_COMMAND_ALIVE_CHECK:
-		/* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
-		buffer_clear(&m);
-		buffer_put_int(&m, allowed);
-		buffer_put_int(&m, getpid());
-		if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
-			error("%s: client msg_send failed", __func__);
-			close(client_fd);
-			buffer_free(&m);
-			return;
-		}
-		buffer_free(&m);
-		close(client_fd);
-		return;
-	default:
-		error("Unsupported command %d", command);
-		buffer_free(&m);
-		close(client_fd);
-		return;
-	}
-
-	/* Reply for SSHMUX_COMMAND_OPEN */
-	buffer_clear(&m);
-	buffer_put_int(&m, allowed);
-	buffer_put_int(&m, getpid());
-	if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
-		error("%s: client msg_send failed", __func__);
-		close(client_fd);
-		buffer_free(&m);
-		return;
-	}
-
-	if (!allowed) {
-		error("Refused control connection");
-		close(client_fd);
-		buffer_free(&m);
-		return;
-	}
-
-	buffer_clear(&m);
-	if (ssh_msg_recv(client_fd, &m) == -1) {
-		error("%s: client msg_recv failed", __func__);
-		close(client_fd);
-		buffer_free(&m);
-		return;
-	}
-	if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
-		error("%s: wrong client version %d", __func__, ver);
-		buffer_free(&m);
-		close(client_fd);
-		return;
-	}
-
-	cctx = xcalloc(1, sizeof(*cctx));
-	cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
-	cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
-	cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
-	cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
-	cctx->term = buffer_get_string(&m, &len);
-
-	cmd = buffer_get_string(&m, &len);
-	buffer_init(&cctx->cmd);
-	buffer_append(&cctx->cmd, cmd, strlen(cmd));
-
-	env_len = buffer_get_int(&m);
-	env_len = MIN(env_len, 4096);
-	debug3("%s: receiving %d env vars", __func__, env_len);
-	if (env_len != 0) {
-		cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
-		for (i = 0; i < env_len; i++)
-			cctx->env[i] = buffer_get_string(&m, &len);
-		cctx->env[i] = NULL;
-	}
-
-	debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
-	    cctx->want_tty, cctx->want_subsys, cmd);
-	xfree(cmd);
-
-	/* Gather fds from client */
-	for(i = 0; i < 3; i++) {
-		if ((new_fd[i] = mm_receive_fd(client_fd)) == -1) {
-			error("%s: failed to receive fd %d from slave",
-			    __func__, i);
-			for (j = 0; j < i; j++)
-				close(new_fd[j]);
-			for (j = 0; j < env_len; j++)
-				xfree(cctx->env[j]);
-			if (env_len > 0)
-				xfree(cctx->env);
-			xfree(cctx->term);
-			buffer_free(&cctx->cmd);
-			close(client_fd);
-			xfree(cctx);
-			return;
-		}
-	}
-
-	debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
-	    new_fd[0], new_fd[1], new_fd[2]);
-
-	/* Try to pick up ttymodes from client before it goes raw */
-	if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
-		error("%s: tcgetattr: %s", __func__, strerror(errno));
-
-	/* This roundtrip is just for synchronisation of ttymodes */
-	buffer_clear(&m);
-	if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
-		error("%s: client msg_send failed", __func__);
-		close(client_fd);
-		close(new_fd[0]);
-		close(new_fd[1]);
-		close(new_fd[2]);
-		buffer_free(&m);
-		xfree(cctx->term);
-		if (env_len != 0) {
-			for (i = 0; i < env_len; i++)
-				xfree(cctx->env[i]);
-			xfree(cctx->env);
-		}
-		return;
-	}
-	buffer_free(&m);
-
-	/* enable nonblocking unless tty */
-	if (!isatty(new_fd[0]))
-		set_nonblock(new_fd[0]);
-	if (!isatty(new_fd[1]))
-		set_nonblock(new_fd[1]);
-	if (!isatty(new_fd[2]))
-		set_nonblock(new_fd[2]);
-
-	set_nonblock(client_fd);
-
-	window = CHAN_SES_WINDOW_DEFAULT;
-	packetmax = CHAN_SES_PACKET_DEFAULT;
-	if (cctx->want_tty) {
-		window >>= 1;
-		packetmax >>= 1;
-	}
-	
-	c = channel_new("session", SSH_CHANNEL_OPENING,
-	    new_fd[0], new_fd[1], new_fd[2], window, packetmax,
-	    CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
-
-	/* XXX */
-	c->ctl_fd = client_fd;
-
-	debug3("%s: channel_new: %d", __func__, c->self);
-
-	channel_send_open(c->self);
-	channel_register_open_confirm(c->self,
-	    client_extra_session2_setup, cctx);
-}
-
-static void
 process_cmdline(void)
 {
 	void (*handler)(int);
@@ -1440,8 +1151,8 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 	connection_in = packet_get_connection_in();
 	connection_out = packet_get_connection_out();
 	max_fd = MAX(connection_in, connection_out);
-	if (control_fd != -1)
-		max_fd = MAX(max_fd, control_fd);
+	if (muxserver_sock != -1)
+		max_fd = MAX(max_fd, muxserver_sock);
 
 	if (!compat20) {
 		/* enable nonblocking unless tty */
@@ -1561,7 +1272,10 @@ client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
 		client_process_net_input(readset);
 
 		/* Accept control connections.  */
-		client_process_control(readset);
+		if (muxserver_sock != -1 &&FD_ISSET(muxserver_sock, readset)) {
+			if (muxserver_accept_control())
+				quit_pending = 1;
+		}
 
 		if (quit_pending)
 			break;
@@ -2143,7 +1857,7 @@ cleanup_exit(int i)
 {
 	leave_raw_mode();
 	leave_non_blocking();
-	if (options.control_path != NULL && control_fd != -1)
+	if (options.control_path != NULL && muxserver_sock != -1)
 		unlink(options.control_path);
 	_exit(i);
 }
diff --git a/usr.bin/ssh/clientloop.h b/usr.bin/ssh/clientloop.h
index cb2d7c08949..6f8e701233b 100644
--- a/usr.bin/ssh/clientloop.h
+++ b/usr.bin/ssh/clientloop.h
@@ -1,4 +1,4 @@
-/* $OpenBSD: clientloop.h,v 1.18 2008/05/08 13:06:11 djm Exp $ */
+/* $OpenBSD: clientloop.h,v 1.19 2008/05/09 14:18:44 djm Exp $ */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -58,3 +58,21 @@ int	 client_request_tun_fwd(int, int, int);
 #define SSHMUX_FLAG_SUBSYS		(1<<1)	/* Subsystem request on open */
 #define SSHMUX_FLAG_X11_FWD		(1<<2)	/* Request X11 forwarding */
 #define SSHMUX_FLAG_AGENT_FWD		(1<<3)	/* Request agent forwarding */
+
+/* Multiplexing routines */
+
+struct mux_session_confirm_ctx {
+	int want_tty;
+	int want_subsys;
+	int want_x_fwd;
+	int want_agent_fwd;
+	Buffer cmd;
+	char *term;
+	struct termios tio;
+	char **env;
+};
+
+/* mux.c */
+void	muxserver_listen(void);
+int	muxserver_accept_control(void);
+void	muxclient(const char *);
diff --git a/usr.bin/ssh/mux.c b/usr.bin/ssh/mux.c
new file mode 100644
index 00000000000..020d561c659
--- /dev/null
+++ b/usr.bin/ssh/mux.c
@@ -0,0 +1,645 @@
+/* $OpenBSD: mux.c,v 1.1 2008/05/09 14:18:44 djm Exp $ */
+/*
+ * Copyright (c) 2002-2008 Damien Miller <djm@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* ssh session multiplexing support */
+
+#include <sys/types.h>
+#include <sys/param.h>
+#include <sys/queue.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdarg.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <util.h>
+#include <paths.h>
+
+#include "xmalloc.h"
+#include "log.h"
+#include "ssh.h"
+#include "pathnames.h"
+#include "misc.h"
+#include "match.h"
+#include "buffer.h"
+#include "channels.h"
+#include "msg.h"
+#include "packet.h"
+#include "monitor_fdpass.h"
+#include "sshpty.h"
+#include "key.h"
+#include "readconf.h"
+#include "clientloop.h"
+
+/* from ssh.c */
+extern int tty_flag;
+extern Options options;
+extern int stdin_null_flag;
+extern char *host;
+int subsystem_flag;
+extern Buffer command;
+
+/* fd to control socket */
+int muxserver_sock = -1;
+
+/* Multiplexing control command */
+u_int muxclient_command = 0;
+
+/* Set when signalled. */
+static volatile sig_atomic_t muxclient_terminate = 0;
+
+/* PID of multiplex server */
+static u_int muxserver_pid = 0;
+
+
+/* ** Multiplexing master support */
+
+/* Prepare a mux master to listen on a Unix domain socket. */
+void
+muxserver_listen(void)
+{
+	struct sockaddr_un addr;
+	mode_t old_umask;
+
+	if (options.control_path == NULL ||
+	    options.control_master == SSHCTL_MASTER_NO)
+		return;
+
+	debug("setting up multiplex master socket");
+
+	memset(&addr, '\0', sizeof(addr));
+	addr.sun_family = AF_UNIX;
+	addr.sun_len = offsetof(struct sockaddr_un, sun_path) +
+	    strlen(options.control_path) + 1;
+
+	if (strlcpy(addr.sun_path, options.control_path,
+	    sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
+		fatal("ControlPath too long");
+
+	if ((muxserver_sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
+		fatal("%s socket(): %s", __func__, strerror(errno));
+
+	old_umask = umask(0177);
+	if (bind(muxserver_sock, (struct sockaddr *)&addr, addr.sun_len) == -1) {
+		muxserver_sock = -1;
+		if (errno == EINVAL || errno == EADDRINUSE)
+			fatal("ControlSocket %s already exists",
+			    options.control_path);
+		else
+			fatal("%s bind(): %s", __func__, strerror(errno));
+	}
+	umask(old_umask);
+
+	if (listen(muxserver_sock, 64) == -1)
+		fatal("%s listen(): %s", __func__, strerror(errno));
+
+	set_nonblock(muxserver_sock);
+}
+
+/* Callback on open confirmation in mux master for a mux client session. */
+static void
+client_extra_session2_setup(int id, void *arg)
+{
+	struct mux_session_confirm_ctx *cctx = arg;
+	const char *display;
+	Channel *c;
+	int i;
+
+	if (cctx == NULL)
+		fatal("%s: cctx == NULL", __func__);
+	if ((c = channel_lookup(id)) == NULL)
+		fatal("%s: no channel for id %d", __func__, id);
+
+	display = getenv("DISPLAY");
+	if (cctx->want_x_fwd && options.forward_x11 && display != NULL) {
+		char *proto, *data;
+		/* Get reasonable local authentication information. */
+		client_x11_get_proto(display, options.xauth_location,
+		    options.forward_x11_trusted, &proto, &data);
+		/* Request forwarding with authentication spoofing. */
+		debug("Requesting X11 forwarding with authentication spoofing.");
+		x11_request_forwarding_with_spoofing(id, display, proto, data);
+		/* XXX wait for reply */
+	}
+
+	if (cctx->want_agent_fwd && options.forward_agent) {
+		debug("Requesting authentication agent forwarding.");
+		channel_request_start(id, "auth-agent-req@openssh.com", 0);
+		packet_send();
+	}
+
+	client_session2_setup(id, cctx->want_tty, cctx->want_subsys,
+	    cctx->term, &cctx->tio, c->rfd, &cctx->cmd, cctx->env);
+
+	c->open_confirm_ctx = NULL;
+	buffer_free(&cctx->cmd);
+	xfree(cctx->term);
+	if (cctx->env != NULL) {
+		for (i = 0; cctx->env[i] != NULL; i++)
+			xfree(cctx->env[i]);
+		xfree(cctx->env);
+	}
+	xfree(cctx);
+}
+
+/*
+ * Accept a connection on the mux master socket and process the
+ * client's request. Returns flag indicating whether mux master should
+ * begin graceful close.
+ */
+int
+muxserver_accept_control(void)
+{
+	Buffer m;
+	Channel *c;
+	int client_fd, new_fd[3], ver, allowed, window, packetmax;
+	socklen_t addrlen;
+	struct sockaddr_storage addr;
+	struct mux_session_confirm_ctx *cctx;
+	char *cmd;
+	u_int i, j, len, env_len, mux_command, flags;
+	uid_t euid;
+	gid_t egid;
+	int start_close = 0;
+
+	/*
+	 * Accept connection on control socket
+	 */
+	memset(&addr, 0, sizeof(addr));
+	addrlen = sizeof(addr);
+	if ((client_fd = accept(muxserver_sock,
+	    (struct sockaddr*)&addr, &addrlen)) == -1) {
+		error("%s accept: %s", __func__, strerror(errno));
+		return 0;
+	}
+
+	if (getpeereid(client_fd, &euid, &egid) < 0) {
+		error("%s getpeereid failed: %s", __func__, strerror(errno));
+		close(client_fd);
+		return 0;
+	}
+	if ((euid != 0) && (getuid() != euid)) {
+		error("control mode uid mismatch: peer euid %u != uid %u",
+		    (u_int) euid, (u_int) getuid());
+		close(client_fd);
+		return 0;
+	}
+
+	/* XXX handle asynchronously */
+	unset_nonblock(client_fd);
+
+	/* Read command */
+	buffer_init(&m);
+	if (ssh_msg_recv(client_fd, &m) == -1) {
+		error("%s: client msg_recv failed", __func__);
+		close(client_fd);
+		buffer_free(&m);
+		return 0;
+	}
+	if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
+		error("%s: wrong client version %d", __func__, ver);
+		buffer_free(&m);
+		close(client_fd);
+		return 0;
+	}
+
+	allowed = 1;
+	mux_command = buffer_get_int(&m);
+	flags = buffer_get_int(&m);
+
+	buffer_clear(&m);
+
+	switch (mux_command) {
+	case SSHMUX_COMMAND_OPEN:
+		if (options.control_master == SSHCTL_MASTER_ASK ||
+		    options.control_master == SSHCTL_MASTER_AUTO_ASK)
+			allowed = ask_permission("Allow shared connection "
+			    "to %s? ", host);
+		/* continue below */
+		break;
+	case SSHMUX_COMMAND_TERMINATE:
+		if (options.control_master == SSHCTL_MASTER_ASK ||
+		    options.control_master == SSHCTL_MASTER_AUTO_ASK)
+			allowed = ask_permission("Terminate shared connection "
+			    "to %s? ", host);
+		if (allowed)
+			start_close = 1;
+		/* FALLTHROUGH */
+	case SSHMUX_COMMAND_ALIVE_CHECK:
+		/* Reply for SSHMUX_COMMAND_TERMINATE and ALIVE_CHECK */
+		buffer_clear(&m);
+		buffer_put_int(&m, allowed);
+		buffer_put_int(&m, getpid());
+		if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
+			error("%s: client msg_send failed", __func__);
+			close(client_fd);
+			buffer_free(&m);
+			return start_close;
+		}
+		buffer_free(&m);
+		close(client_fd);
+		return start_close;
+	default:
+		error("Unsupported command %d", mux_command);
+		buffer_free(&m);
+		close(client_fd);
+		return 0;
+	}
+
+	/* Reply for SSHMUX_COMMAND_OPEN */
+	buffer_clear(&m);
+	buffer_put_int(&m, allowed);
+	buffer_put_int(&m, getpid());
+	if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
+		error("%s: client msg_send failed", __func__);
+		close(client_fd);
+		buffer_free(&m);
+		return 0;
+	}
+
+	if (!allowed) {
+		error("Refused control connection");
+		close(client_fd);
+		buffer_free(&m);
+		return 0;
+	}
+
+	buffer_clear(&m);
+	if (ssh_msg_recv(client_fd, &m) == -1) {
+		error("%s: client msg_recv failed", __func__);
+		close(client_fd);
+		buffer_free(&m);
+		return 0;
+	}
+	if ((ver = buffer_get_char(&m)) != SSHMUX_VER) {
+		error("%s: wrong client version %d", __func__, ver);
+		buffer_free(&m);
+		close(client_fd);
+		return 0;
+	}
+
+	cctx = xcalloc(1, sizeof(*cctx));
+	cctx->want_tty = (flags & SSHMUX_FLAG_TTY) != 0;
+	cctx->want_subsys = (flags & SSHMUX_FLAG_SUBSYS) != 0;
+	cctx->want_x_fwd = (flags & SSHMUX_FLAG_X11_FWD) != 0;
+	cctx->want_agent_fwd = (flags & SSHMUX_FLAG_AGENT_FWD) != 0;
+	cctx->term = buffer_get_string(&m, &len);
+
+	cmd = buffer_get_string(&m, &len);
+	buffer_init(&cctx->cmd);
+	buffer_append(&cctx->cmd, cmd, strlen(cmd));
+
+	env_len = buffer_get_int(&m);
+	env_len = MIN(env_len, 4096);
+	debug3("%s: receiving %d env vars", __func__, env_len);
+	if (env_len != 0) {
+		cctx->env = xcalloc(env_len + 1, sizeof(*cctx->env));
+		for (i = 0; i < env_len; i++)
+			cctx->env[i] = buffer_get_string(&m, &len);
+		cctx->env[i] = NULL;
+	}
+
+	debug2("%s: accepted tty %d, subsys %d, cmd %s", __func__,
+	    cctx->want_tty, cctx->want_subsys, cmd);
+	xfree(cmd);
+
+	/* Gather fds from client */
+	for(i = 0; i < 3; i++) {
+		if ((new_fd[i] = mm_receive_fd(client_fd)) == -1) {
+			error("%s: failed to receive fd %d from slave",
+			    __func__, i);
+			for (j = 0; j < i; j++)
+				close(new_fd[j]);
+			for (j = 0; j < env_len; j++)
+				xfree(cctx->env[j]);
+			if (env_len > 0)
+				xfree(cctx->env);
+			xfree(cctx->term);
+			buffer_free(&cctx->cmd);
+			close(client_fd);
+			xfree(cctx);
+			return 0;
+		}
+	}
+
+	debug2("%s: got fds stdin %d, stdout %d, stderr %d", __func__,
+	    new_fd[0], new_fd[1], new_fd[2]);
+
+	/* Try to pick up ttymodes from client before it goes raw */
+	if (cctx->want_tty && tcgetattr(new_fd[0], &cctx->tio) == -1)
+		error("%s: tcgetattr: %s", __func__, strerror(errno));
+
+	/* This roundtrip is just for synchronisation of ttymodes */
+	buffer_clear(&m);
+	if (ssh_msg_send(client_fd, SSHMUX_VER, &m) == -1) {
+		error("%s: client msg_send failed", __func__);
+		close(client_fd);
+		close(new_fd[0]);
+		close(new_fd[1]);
+		close(new_fd[2]);
+		buffer_free(&m);
+		xfree(cctx->term);
+		if (env_len != 0) {
+			for (i = 0; i < env_len; i++)
+				xfree(cctx->env[i]);
+			xfree(cctx->env);
+		}
+		return 0;
+	}
+	buffer_free(&m);
+
+	/* enable nonblocking unless tty */
+	if (!isatty(new_fd[0]))
+		set_nonblock(new_fd[0]);
+	if (!isatty(new_fd[1]))
+		set_nonblock(new_fd[1]);
+	if (!isatty(new_fd[2]))
+		set_nonblock(new_fd[2]);
+
+	set_nonblock(client_fd);
+
+	window = CHAN_SES_WINDOW_DEFAULT;
+	packetmax = CHAN_SES_PACKET_DEFAULT;
+	if (cctx->want_tty) {
+		window >>= 1;
+		packetmax >>= 1;
+	}
+	
+	c = channel_new("session", SSH_CHANNEL_OPENING,
+	    new_fd[0], new_fd[1], new_fd[2], window, packetmax,
+	    CHAN_EXTENDED_WRITE, "client-session", /*nonblock*/0);
+
+	/* XXX */
+	c->ctl_fd = client_fd;
+
+	debug3("%s: channel_new: %d", __func__, c->self);
+
+	channel_send_open(c->self);
+	channel_register_open_confirm(c->self,
+	    client_extra_session2_setup, cctx);
+	return 0;
+}
+
+/* ** Multiplexing client support */
+
+/* Exit signal handler */
+static void
+control_client_sighandler(int signo)
+{
+	muxclient_terminate = signo;
+}
+
+/*
+ * Relay signal handler - used to pass some signals from mux client to
+ * mux master.
+ */
+static void
+control_client_sigrelay(int signo)
+{
+	int save_errno = errno;
+
+	if (muxserver_pid > 1)
+		kill(muxserver_pid, signo);
+
+	errno = save_errno;
+}
+
+/* Check mux client environment variables before passing them to mux master. */
+static int
+env_permitted(char *env)
+{
+	int i, ret;
+	char name[1024], *cp;
+
+	if ((cp = strchr(env, '=')) == NULL || cp == env)
+		return (0);
+	ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
+	if (ret <= 0 || (size_t)ret >= sizeof(name))
+		fatal("env_permitted: name '%.100s...' too long", env);
+
+	for (i = 0; i < options.num_send_env; i++)
+		if (match_pattern(name, options.send_env[i]))
+			return (1);
+
+	return (0);
+}
+
+/* Multiplex client main loop. */
+void
+muxclient(const char *path)
+{
+	struct sockaddr_un addr;
+	int i, r, fd, sock, exitval[2], num_env;
+	Buffer m;
+	char *term;
+	extern char **environ;
+	u_int  flags;
+
+	if (muxclient_command == 0)
+		muxclient_command = SSHMUX_COMMAND_OPEN;
+
+	switch (options.control_master) {
+	case SSHCTL_MASTER_AUTO:
+	case SSHCTL_MASTER_AUTO_ASK:
+		debug("auto-mux: Trying existing master");
+		/* FALLTHROUGH */
+	case SSHCTL_MASTER_NO:
+		break;
+	default:
+		return;
+	}
+
+	memset(&addr, '\0', sizeof(addr));
+	addr.sun_family = AF_UNIX;
+	addr.sun_len = offsetof(struct sockaddr_un, sun_path) +
+	    strlen(path) + 1;
+
+	if (strlcpy(addr.sun_path, path,
+	    sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
+		fatal("ControlPath too long");
+
+	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
+		fatal("%s socket(): %s", __func__, strerror(errno));
+
+	if (connect(sock, (struct sockaddr *)&addr, addr.sun_len) == -1) {
+		if (muxclient_command != SSHMUX_COMMAND_OPEN) {
+			fatal("Control socket connect(%.100s): %s", path,
+			    strerror(errno));
+		}
+		if (errno == ENOENT)
+			debug("Control socket \"%.100s\" does not exist", path);
+		else {
+			error("Control socket connect(%.100s): %s", path,
+			    strerror(errno));
+		}
+		close(sock);
+		return;
+	}
+
+	if (stdin_null_flag) {
+		if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
+			fatal("open(/dev/null): %s", strerror(errno));
+		if (dup2(fd, STDIN_FILENO) == -1)
+			fatal("dup2: %s", strerror(errno));
+		if (fd > STDERR_FILENO)
+			close(fd);
+	}
+
+	term = getenv("TERM");
+
+	flags = 0;
+	if (tty_flag)
+		flags |= SSHMUX_FLAG_TTY;
+	if (subsystem_flag)
+		flags |= SSHMUX_FLAG_SUBSYS;
+	if (options.forward_x11)
+		flags |= SSHMUX_FLAG_X11_FWD;
+	if (options.forward_agent)
+		flags |= SSHMUX_FLAG_AGENT_FWD;
+
+	signal(SIGPIPE, SIG_IGN);
+
+	buffer_init(&m);
+
+	/* Send our command to server */
+	buffer_put_int(&m, muxclient_command);
+	buffer_put_int(&m, flags);
+	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
+		fatal("%s: msg_send", __func__);
+	buffer_clear(&m);
+
+	/* Get authorisation status and PID of controlee */
+	if (ssh_msg_recv(sock, &m) == -1)
+		fatal("%s: msg_recv", __func__);
+	if (buffer_get_char(&m) != SSHMUX_VER)
+		fatal("%s: wrong version", __func__);
+	if (buffer_get_int(&m) != 1)
+		fatal("Connection to master denied");
+	muxserver_pid = buffer_get_int(&m);
+
+	buffer_clear(&m);
+
+	switch (muxclient_command) {
+	case SSHMUX_COMMAND_ALIVE_CHECK:
+		fprintf(stderr, "Master running (pid=%d)\r\n",
+		    muxserver_pid);
+		exit(0);
+	case SSHMUX_COMMAND_TERMINATE:
+		fprintf(stderr, "Exit request sent.\r\n");
+		exit(0);
+	case SSHMUX_COMMAND_OPEN:
+		/* continue below */
+		break;
+	default:
+		fatal("silly muxclient_command %d", muxclient_command);
+	}
+
+	/* SSHMUX_COMMAND_OPEN */
+	buffer_put_cstring(&m, term ? term : "");
+	buffer_append(&command, "\0", 1);
+	buffer_put_cstring(&m, buffer_ptr(&command));
+
+	if (options.num_send_env == 0 || environ == NULL) {
+		buffer_put_int(&m, 0);
+	} else {
+		/* Pass environment */
+		num_env = 0;
+		for (i = 0; environ[i] != NULL; i++)
+			if (env_permitted(environ[i]))
+				num_env++; /* Count */
+
+		buffer_put_int(&m, num_env);
+
+		for (i = 0; environ[i] != NULL && num_env >= 0; i++)
+			if (env_permitted(environ[i])) {
+				num_env--;
+				buffer_put_cstring(&m, environ[i]);
+			}
+	}
+
+	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
+		fatal("%s: msg_send", __func__);
+
+	if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
+	    mm_send_fd(sock, STDOUT_FILENO) == -1 ||
+	    mm_send_fd(sock, STDERR_FILENO) == -1)
+		fatal("%s: send fds failed", __func__);
+
+	/* Wait for reply, so master has a chance to gather ttymodes */
+	buffer_clear(&m);
+	if (ssh_msg_recv(sock, &m) == -1)
+		fatal("%s: msg_recv", __func__);
+	if (buffer_get_char(&m) != SSHMUX_VER)
+		fatal("%s: wrong version", __func__);
+	buffer_free(&m);
+
+	signal(SIGHUP, control_client_sighandler);
+	signal(SIGINT, control_client_sighandler);
+	signal(SIGTERM, control_client_sighandler);
+	signal(SIGWINCH, control_client_sigrelay);
+
+	if (tty_flag)
+		enter_raw_mode();
+
+	/*
+	 * Stick around until the controlee closes the client_fd.
+	 * Before it does, it is expected to write this process' exit
+	 * value (one int). This process must read the value and wait for
+	 * the closure of the client_fd; if this one closes early, the 
+	 * multiplex master will terminate early too (possibly losing data).
+	 */
+	exitval[0] = 0;
+	for (i = 0; !muxclient_terminate && i < (int)sizeof(exitval);) {
+		r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
+		if (r == 0) {
+			debug2("Received EOF from master");
+			break;
+		}
+		if (r == -1) {
+			if (errno == EINTR)
+				continue;
+			fatal("%s: read %s", __func__, strerror(errno));
+		}
+		i += r;
+	}
+
+	close(sock);
+	leave_raw_mode();
+	if (i > (int)sizeof(int))
+		fatal("%s: master returned too much data (%d > %lu)",
+		    __func__, i, sizeof(int));
+	if (muxclient_terminate) {
+		debug2("Exiting on signal %d", muxclient_terminate);
+		exitval[0] = 255;
+	} else if (i < (int)sizeof(int)) {
+		debug2("Control master terminated unexpectedly");
+		exitval[0] = 255;
+	} else
+		debug2("Received exit status from master %d", exitval[0]);
+
+	if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
+		fprintf(stderr, "Shared connection to %s closed.\r\n", host);
+
+	exit(exitval[0]);
+}
diff --git a/usr.bin/ssh/ssh.c b/usr.bin/ssh/ssh.c
index d6cd504f1af..d71f02f1bba 100644
--- a/usr.bin/ssh/ssh.c
+++ b/usr.bin/ssh/ssh.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: ssh.c,v 1.311 2008/05/08 13:06:11 djm Exp $ */
+/* $OpenBSD: ssh.c,v 1.312 2008/05/09 14:18:44 djm Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -41,14 +41,13 @@
  */
 
 #include <sys/types.h>
-#include <sys/time.h>
-#include <sys/resource.h>
 #include <sys/ioctl.h>
-#include <sys/types.h>
+#include <sys/queue.h>
+#include <sys/resource.h>
 #include <sys/socket.h>
-#include <sys/un.h>
 #include <sys/stat.h>
-#include <sys/queue.h>
+#include <sys/types.h>
+#include <sys/time.h>
 
 #include <ctype.h>
 #include <errno.h>
@@ -90,7 +89,6 @@
 #include "sshpty.h"
 #include "match.h"
 #include "msg.h"
-#include "monitor_fdpass.h"
 #include "uidswap.h"
 #include "version.h"
 
@@ -162,16 +160,6 @@ static int client_global_request_id = 0;
 /* pid of proxycommand child process */
 pid_t proxy_command_pid = 0;
 
-/* fd to control socket */
-int control_fd = -1;
-
-/* Multiplexing control command */
-static u_int mux_command = 0;
-
-/* Only used in control client mode */
-volatile sig_atomic_t control_client_terminate = 0;
-u_int control_server_pid = 0;
-
 /* Prints a help message to the user.  This function never returns. */
 
 static void
@@ -191,7 +179,10 @@ usage(void)
 static int ssh_session(void);
 static int ssh_session2(void);
 static void load_public_identity_files(void);
-static void control_client(const char *path);
+
+/* from muxclient.c */
+void muxclient(const char *);
+void muxserver_listen(void);
 
 /*
  * Main program for the ssh client.
@@ -296,9 +287,9 @@ main(int ac, char **av)
 			break;
 		case 'O':
 			if (strcmp(optarg, "check") == 0)
-				mux_command = SSHMUX_COMMAND_ALIVE_CHECK;
+				muxclient_command = SSHMUX_COMMAND_ALIVE_CHECK;
 			else if (strcmp(optarg, "exit") == 0)
-				mux_command = SSHMUX_COMMAND_TERMINATE;
+				muxclient_command = SSHMUX_COMMAND_TERMINATE;
 			else
 				fatal("Invalid multiplex command.");
 			break;
@@ -667,10 +658,10 @@ main(int ac, char **av)
 		    "r", options.user, "l", thishost, (char *)NULL);
 		xfree(cp);
 	}
-	if (mux_command != 0 && options.control_path == NULL)
+	if (muxclient_command != 0 && options.control_path == NULL)
 		fatal("No ControlPath specified for \"-O\" command");
 	if (options.control_path != NULL)
-		control_client(options.control_path);
+		muxclient(options.control_path);
 
 	timeout_ms = options.connection_timeout * 1000;
 
@@ -789,7 +780,7 @@ main(int ac, char **av)
 	exit_status = compat20 ? ssh_session2() : ssh_session();
 	packet_close();
 
-	if (options.control_path != NULL && control_fd != -1)
+	if (options.control_path != NULL && muxserver_sock != -1)
 		unlink(options.control_path);
 
 	/*
@@ -1044,47 +1035,6 @@ client_global_request_reply_fwd(int type, u_int32_t seq, void *ctxt)
 	}
 }
 
-static void
-ssh_control_listener(void)
-{
-	struct sockaddr_un addr;
-	mode_t old_umask;
-
-	if (options.control_path == NULL ||
-	    options.control_master == SSHCTL_MASTER_NO)
-		return;
-
-	debug("setting up multiplex master socket");
-
-	memset(&addr, '\0', sizeof(addr));
-	addr.sun_family = AF_UNIX;
-	addr.sun_len = offsetof(struct sockaddr_un, sun_path) +
-	    strlen(options.control_path) + 1;
-
-	if (strlcpy(addr.sun_path, options.control_path,
-	    sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
-		fatal("ControlPath too long");
-
-	if ((control_fd = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
-		fatal("%s socket(): %s", __func__, strerror(errno));
-
-	old_umask = umask(0177);
-	if (bind(control_fd, (struct sockaddr *)&addr, addr.sun_len) == -1) {
-		control_fd = -1;
-		if (errno == EINVAL || errno == EADDRINUSE)
-			fatal("ControlSocket %s already exists",
-			    options.control_path);
-		else
-			fatal("%s bind(): %s", __func__, strerror(errno));
-	}
-	umask(old_umask);
-
-	if (listen(control_fd, 64) == -1)
-		fatal("%s listen(): %s", __func__, strerror(errno));
-
-	set_nonblock(control_fd);
-}
-
 /* request pty/x11/agent/tcpfwd/shell for channel */
 static void
 ssh_session2_setup(int id, void *arg)
@@ -1183,7 +1133,7 @@ ssh_session2(void)
 		ssh_local_cmd(options.local_command);
 
 	/* Start listening for multiplex clients */
-	ssh_control_listener();
+	muxserver_listen();
 
 	/* If requested, let ssh continue in the background. */
 	if (fork_after_authentication_flag)
@@ -1252,236 +1202,3 @@ load_public_identity_files(void)
 	xfree(pwdir);
 }
 
-static void
-control_client_sighandler(int signo)
-{
-	control_client_terminate = signo;
-}
-
-static void
-control_client_sigrelay(int signo)
-{
-	int save_errno = errno;
-
-	if (control_server_pid > 1)
-		kill(control_server_pid, signo);
-
-	errno = save_errno;
-}
-
-static int
-env_permitted(char *env)
-{
-	int i, ret;
-	char name[1024], *cp;
-
-	if ((cp = strchr(env, '=')) == NULL || cp == env)
-		return (0);
-	ret = snprintf(name, sizeof(name), "%.*s", (int)(cp - env), env);
-	if (ret <= 0 || (size_t)ret >= sizeof(name))
-		fatal("env_permitted: name '%.100s...' too long", env);
-
-	for (i = 0; i < options.num_send_env; i++)
-		if (match_pattern(name, options.send_env[i]))
-			return (1);
-
-	return (0);
-}
-
-static void
-control_client(const char *path)
-{
-	struct sockaddr_un addr;
-	int i, r, fd, sock, exitval[2], num_env;
-	Buffer m;
-	char *term;
-	extern char **environ;
-	u_int  flags;
-
-	if (mux_command == 0)
-		mux_command = SSHMUX_COMMAND_OPEN;
-
-	switch (options.control_master) {
-	case SSHCTL_MASTER_AUTO:
-	case SSHCTL_MASTER_AUTO_ASK:
-		debug("auto-mux: Trying existing master");
-		/* FALLTHROUGH */
-	case SSHCTL_MASTER_NO:
-		break;
-	default:
-		return;
-	}
-
-	memset(&addr, '\0', sizeof(addr));
-	addr.sun_family = AF_UNIX;
-	addr.sun_len = offsetof(struct sockaddr_un, sun_path) +
-	    strlen(path) + 1;
-
-	if (strlcpy(addr.sun_path, path,
-	    sizeof(addr.sun_path)) >= sizeof(addr.sun_path))
-		fatal("ControlPath too long");
-
-	if ((sock = socket(PF_UNIX, SOCK_STREAM, 0)) < 0)
-		fatal("%s socket(): %s", __func__, strerror(errno));
-
-	if (connect(sock, (struct sockaddr *)&addr, addr.sun_len) == -1) {
-		if (mux_command != SSHMUX_COMMAND_OPEN) {
-			fatal("Control socket connect(%.100s): %s", path,
-			    strerror(errno));
-		}
-		if (errno == ENOENT)
-			debug("Control socket \"%.100s\" does not exist", path);
-		else {
-			error("Control socket connect(%.100s): %s", path,
-			    strerror(errno));
-		}
-		close(sock);
-		return;
-	}
-
-	if (stdin_null_flag) {
-		if ((fd = open(_PATH_DEVNULL, O_RDONLY)) == -1)
-			fatal("open(/dev/null): %s", strerror(errno));
-		if (dup2(fd, STDIN_FILENO) == -1)
-			fatal("dup2: %s", strerror(errno));
-		if (fd > STDERR_FILENO)
-			close(fd);
-	}
-
-	term = getenv("TERM");
-
-	flags = 0;
-	if (tty_flag)
-		flags |= SSHMUX_FLAG_TTY;
-	if (subsystem_flag)
-		flags |= SSHMUX_FLAG_SUBSYS;
-	if (options.forward_x11)
-		flags |= SSHMUX_FLAG_X11_FWD;
-	if (options.forward_agent)
-		flags |= SSHMUX_FLAG_AGENT_FWD;
-
-	signal(SIGPIPE, SIG_IGN);
-
-	buffer_init(&m);
-
-	/* Send our command to server */
-	buffer_put_int(&m, mux_command);
-	buffer_put_int(&m, flags);
-	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
-		fatal("%s: msg_send", __func__);
-	buffer_clear(&m);
-
-	/* Get authorisation status and PID of controlee */
-	if (ssh_msg_recv(sock, &m) == -1)
-		fatal("%s: msg_recv", __func__);
-	if (buffer_get_char(&m) != SSHMUX_VER)
-		fatal("%s: wrong version", __func__);
-	if (buffer_get_int(&m) != 1)
-		fatal("Connection to master denied");
-	control_server_pid = buffer_get_int(&m);
-
-	buffer_clear(&m);
-
-	switch (mux_command) {
-	case SSHMUX_COMMAND_ALIVE_CHECK:
-		fprintf(stderr, "Master running (pid=%d)\r\n",
-		    control_server_pid);
-		exit(0);
-	case SSHMUX_COMMAND_TERMINATE:
-		fprintf(stderr, "Exit request sent.\r\n");
-		exit(0);
-	case SSHMUX_COMMAND_OPEN:
-		/* continue below */
-		break;
-	default:
-		fatal("silly mux_command %d", mux_command);
-	}
-
-	/* SSHMUX_COMMAND_OPEN */
-	buffer_put_cstring(&m, term ? term : "");
-	buffer_append(&command, "\0", 1);
-	buffer_put_cstring(&m, buffer_ptr(&command));
-
-	if (options.num_send_env == 0 || environ == NULL) {
-		buffer_put_int(&m, 0);
-	} else {
-		/* Pass environment */
-		num_env = 0;
-		for (i = 0; environ[i] != NULL; i++)
-			if (env_permitted(environ[i]))
-				num_env++; /* Count */
-
-		buffer_put_int(&m, num_env);
-
-		for (i = 0; environ[i] != NULL && num_env >= 0; i++)
-			if (env_permitted(environ[i])) {
-				num_env--;
-				buffer_put_cstring(&m, environ[i]);
-			}
-	}
-
-	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
-		fatal("%s: msg_send", __func__);
-
-	if (mm_send_fd(sock, STDIN_FILENO) == -1 ||
-	    mm_send_fd(sock, STDOUT_FILENO) == -1 ||
-	    mm_send_fd(sock, STDERR_FILENO) == -1)
-		fatal("%s: send fds failed", __func__);
-
-	/* Wait for reply, so master has a chance to gather ttymodes */
-	buffer_clear(&m);
-	if (ssh_msg_recv(sock, &m) == -1)
-		fatal("%s: msg_recv", __func__);
-	if (buffer_get_char(&m) != SSHMUX_VER)
-		fatal("%s: wrong version", __func__);
-	buffer_free(&m);
-
-	signal(SIGHUP, control_client_sighandler);
-	signal(SIGINT, control_client_sighandler);
-	signal(SIGTERM, control_client_sighandler);
-	signal(SIGWINCH, control_client_sigrelay);
-
-	if (tty_flag)
-		enter_raw_mode();
-
-	/*
-	 * Stick around until the controlee closes the client_fd.
-	 * Before it does, it is expected to write this process' exit
-	 * value (one int). This process must read the value and wait for
-	 * the closure of the client_fd; if this one closes early, the 
-	 * multiplex master will terminate early too (possibly losing data).
-	 */
-	exitval[0] = 0;
-	for (i = 0; !control_client_terminate && i < (int)sizeof(exitval);) {
-		r = read(sock, (char *)exitval + i, sizeof(exitval) - i);
-		if (r == 0) {
-			debug2("Received EOF from master");
-			break;
-		}
-		if (r == -1) {
-			if (errno == EINTR)
-				continue;
-			fatal("%s: read %s", __func__, strerror(errno));
-		}
-		i += r;
-	}
-
-	close(sock);
-	leave_raw_mode();
-	if (i > (int)sizeof(int))
-		fatal("%s: master returned too much data (%d > %lu)",
-		    __func__, i, sizeof(int));
-	if (control_client_terminate) {
-		debug2("Exiting on signal %d", control_client_terminate);
-		exitval[0] = 255;
-	} else if (i < (int)sizeof(int)) {
-		debug2("Control master terminated unexpectedly");
-		exitval[0] = 255;
-	} else
-		debug2("Received exit status from master %d", exitval[0]);
-
-	if (tty_flag && options.log_level != SYSLOG_LEVEL_QUIET)
-		fprintf(stderr, "Shared connection to %s closed.\r\n", host);
-
-	exit(exitval[0]);
-}
diff --git a/usr.bin/ssh/ssh/Makefile b/usr.bin/ssh/ssh/Makefile
index ef560aca7af..dbbd0d0e9e3 100644
--- a/usr.bin/ssh/ssh/Makefile
+++ b/usr.bin/ssh/ssh/Makefile
@@ -1,4 +1,4 @@
-#	$OpenBSD: Makefile,v 1.51 2003/11/21 11:57:03 djm Exp $
+#	$OpenBSD: Makefile,v 1.52 2008/05/09 14:18:45 djm Exp $
 
 .PATH:		${.CURDIR}/..
 
@@ -13,7 +13,7 @@ LINKS=	${BINDIR}/ssh ${BINDIR}/slogin
 MLINKS=	ssh.1 slogin.1
 
 SRCS=	ssh.c readconf.c clientloop.c sshtty.c \
-	sshconnect.c sshconnect1.c sshconnect2.c
+	sshconnect.c sshconnect1.c sshconnect2.c mux.c
 
 .include <bsd.own.mk> # for AFS