X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/aacab402991cf3ce8991ada093d5f3058f4170af..51529944e9ab39541ed61a8267e7a4e003b1e271:/mux.c?ds=sidebyside

diff --git a/mux.c b/mux.c
index f5e68f65..239edd5f 100644
--- a/mux.c
+++ b/mux.c
@@ -1,4 +1,4 @@
-/* $OpenBSD: mux.c,v 1.3 2008/06/12 05:32:30 djm Exp $ */
+/* $OpenBSD: mux.c,v 1.9 2010/01/09 05:04:24 djm Exp $ */
 /*
  * Copyright (c) 2002-2008 Damien Miller <djm@openbsd.org>
  *
@@ -82,10 +82,11 @@
 
 /* from ssh.c */
 extern int tty_flag;
+extern int force_tty_flag;
 extern Options options;
 extern int stdin_null_flag;
 extern char *host;
-int subsystem_flag;
+extern int subsystem_flag;
 extern Buffer command;
 
 /* Context for session open confirmation callback */
@@ -144,10 +145,16 @@ muxserver_listen(void)
 	old_umask = umask(0177);
 	if (bind(muxserver_sock, (struct sockaddr *)&addr, addr_len) == -1) {
 		muxserver_sock = -1;
-		if (errno == EINVAL || errno == EADDRINUSE)
-			fatal("ControlSocket %s already exists",
-			    options.control_path);
-		else
+		if (errno == EINVAL || errno == EADDRINUSE) {
+			error("ControlSocket %s already exists, "
+			    "disabling multiplexing", options.control_path);
+			close(muxserver_sock);
+			muxserver_sock = -1;
+			xfree(options.control_path);
+			options.control_path = NULL;
+			options.control_master = SSHCTL_MASTER_NO;
+			return;
+		} else
 			fatal("%s bind(): %s", __func__, strerror(errno));
 	}
 	umask(old_umask);
@@ -436,6 +443,7 @@ muxserver_accept_control(void)
 	if (cctx->want_tty && escape_char != 0xffffffff) {
 		channel_register_filter(c->self,
 		    client_simple_escape_filter, NULL,
+		    client_filter_cleanup,
 		    client_new_escape_filter_ctx((int)escape_char));
 	}
 
@@ -499,7 +507,7 @@ muxclient(const char *path)
 	Buffer m;
 	char *term;
 	extern char **environ;
-	u_int  flags;
+	u_int allowed, flags;
 
 	if (muxclient_command == 0)
 		muxclient_command = SSHMUX_COMMAND_OPEN;
@@ -570,17 +578,38 @@ muxclient(const char *path)
 	/* 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__);
+	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1) {
+		error("%s: msg_send", __func__);
+ muxerr:
+		close(sock);
+		buffer_free(&m);
+		if (muxclient_command != SSHMUX_COMMAND_OPEN)
+			cleanup_exit(255);
+		logit("Falling back to non-multiplexed connection");
+		xfree(options.control_path);
+		options.control_path = NULL;
+		options.control_master = SSHCTL_MASTER_NO;
+		return;
+	}
 	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");
+	if (ssh_msg_recv(sock, &m) == -1) {
+		error("%s: Did not receive reply from master", __func__);
+		goto muxerr;
+	}
+	if (buffer_get_char(&m) != SSHMUX_VER) {
+		error("%s: Master replied with wrong version", __func__);
+		goto muxerr;
+	}
+	if (buffer_get_int_ret(&allowed, &m) != 0) {
+		error("%s: bad server reply", __func__);
+		goto muxerr;
+	}
+	if (allowed != 1) {
+		error("Connection to master denied");
+		goto muxerr;
+	}
 	muxserver_pid = buffer_get_int(&m);
 
 	buffer_clear(&m);
@@ -624,13 +653,22 @@ muxclient(const char *path)
 		fatal("unrecognised muxclient_command %d", muxclient_command);
 	}
 
-	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1)
-		fatal("%s: msg_send", __func__);
+	if (ssh_msg_send(sock, SSHMUX_VER, &m) == -1) {
+		error("%s: msg_send", __func__);
+		goto muxerr;
+	}
 
 	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__);
+	    mm_send_fd(sock, STDERR_FILENO) == -1) {
+		error("%s: send fds failed", __func__);
+		goto muxerr;
+	}
+
+	/*
+	 * Mux errors are non-recoverable from this point as the master
+	 * has ownership of the session now.
+	 */
 
 	/* Wait for reply, so master has a chance to gather ttymodes */
 	buffer_clear(&m);
@@ -646,7 +684,7 @@ muxclient(const char *path)
 	signal(SIGWINCH, control_client_sigrelay);
 
 	if (tty_flag)
-		enter_raw_mode();
+		enter_raw_mode(force_tty_flag);
 
 	/*
 	 * Stick around until the controlee closes the client_fd.
@@ -671,10 +709,10 @@ muxclient(const char *path)
 	}
 
 	close(sock);
-	leave_raw_mode();
+	leave_raw_mode(force_tty_flag);
 	if (i > (int)sizeof(int))
 		fatal("%s: master returned too much data (%d > %lu)",
-		    __func__, i, sizeof(int));
+		    __func__, i, (u_long)sizeof(int));
 	if (muxclient_terminate) {
 		debug2("Exiting on signal %d", muxclient_terminate);
 		exitval[0] = 255;