xref: /dragonfly/crypto/openssh/clientloop.c (revision 650094e1)
1 /* $OpenBSD: clientloop.c,v 1.236 2011/06/22 22:08:42 djm Exp $ */
2 /*
3  * Author: Tatu Ylonen <ylo@cs.hut.fi>
4  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5  *                    All rights reserved
6  * The main loop for the interactive session (client side).
7  *
8  * As far as I am concerned, the code I have written for this software
9  * can be used freely for any purpose.  Any derived versions of this
10  * software must be clearly marked as such, and if the derived work is
11  * incompatible with the protocol description in the RFC file, it must be
12  * called by a name other than "ssh" or "Secure Shell".
13  *
14  *
15  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
16  *
17  * Redistribution and use in source and binary forms, with or without
18  * modification, are permitted provided that the following conditions
19  * are met:
20  * 1. Redistributions of source code must retain the above copyright
21  *    notice, this list of conditions and the following disclaimer.
22  * 2. Redistributions in binary form must reproduce the above copyright
23  *    notice, this list of conditions and the following disclaimer in the
24  *    documentation and/or other materials provided with the distribution.
25  *
26  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36  *
37  *
38  * SSH2 support added by Markus Friedl.
39  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
40  *
41  * Redistribution and use in source and binary forms, with or without
42  * modification, are permitted provided that the following conditions
43  * are met:
44  * 1. Redistributions of source code must retain the above copyright
45  *    notice, this list of conditions and the following disclaimer.
46  * 2. Redistributions in binary form must reproduce the above copyright
47  *    notice, this list of conditions and the following disclaimer in the
48  *    documentation and/or other materials provided with the distribution.
49  *
50  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
51  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
52  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
53  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
54  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
55  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
56  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
57  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
58  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
59  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
60  */
61 
62 #include "includes.h"
63 
64 #include <sys/types.h>
65 #include <sys/ioctl.h>
66 #include <sys/param.h>
67 #ifdef HAVE_SYS_STAT_H
68 # include <sys/stat.h>
69 #endif
70 #ifdef HAVE_SYS_TIME_H
71 # include <sys/time.h>
72 #endif
73 #include <sys/socket.h>
74 
75 #include <ctype.h>
76 #include <errno.h>
77 #ifdef HAVE_PATHS_H
78 #include <paths.h>
79 #endif
80 #include <signal.h>
81 #include <stdarg.h>
82 #include <stdio.h>
83 #include <stdlib.h>
84 #include <string.h>
85 #include <termios.h>
86 #include <pwd.h>
87 #include <unistd.h>
88 
89 #include "openbsd-compat/sys-queue.h"
90 #include "xmalloc.h"
91 #include "ssh.h"
92 #include "ssh1.h"
93 #include "ssh2.h"
94 #include "packet.h"
95 #include "buffer.h"
96 #include "compat.h"
97 #include "channels.h"
98 #include "dispatch.h"
99 #include "key.h"
100 #include "cipher.h"
101 #include "kex.h"
102 #include "log.h"
103 #include "readconf.h"
104 #include "clientloop.h"
105 #include "sshconnect.h"
106 #include "authfd.h"
107 #include "atomicio.h"
108 #include "sshpty.h"
109 #include "misc.h"
110 #include "match.h"
111 #include "msg.h"
112 #include "roaming.h"
113 
114 /* import options */
115 extern Options options;
116 
117 /* Flag indicating that stdin should be redirected from /dev/null. */
118 extern int stdin_null_flag;
119 
120 /* Flag indicating that no shell has been requested */
121 extern int no_shell_flag;
122 
123 /* Control socket */
124 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
125 
126 /*
127  * Name of the host we are connecting to.  This is the name given on the
128  * command line, or the HostName specified for the user-supplied name in a
129  * configuration file.
130  */
131 extern char *host;
132 
133 /*
134  * Flag to indicate that we have received a window change signal which has
135  * not yet been processed.  This will cause a message indicating the new
136  * window size to be sent to the server a little later.  This is volatile
137  * because this is updated in a signal handler.
138  */
139 static volatile sig_atomic_t received_window_change_signal = 0;
140 static volatile sig_atomic_t received_signal = 0;
141 
142 /* Flag indicating whether the user's terminal is in non-blocking mode. */
143 static int in_non_blocking_mode = 0;
144 
145 /* Time when backgrounded control master using ControlPersist should exit */
146 static time_t control_persist_exit_time = 0;
147 
148 /* Common data for the client loop code. */
149 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
150 static int escape_char1;	/* Escape character. (proto1 only) */
151 static int escape_pending1;	/* Last character was an escape (proto1 only) */
152 static int last_was_cr;		/* Last character was a newline. */
153 static int exit_status;		/* Used to store the command exit status. */
154 static int stdin_eof;		/* EOF has been encountered on stderr. */
155 static Buffer stdin_buffer;	/* Buffer for stdin data. */
156 static Buffer stdout_buffer;	/* Buffer for stdout data. */
157 static Buffer stderr_buffer;	/* Buffer for stderr data. */
158 static u_int buffer_high;	/* Soft max buffer size. */
159 static int connection_in;	/* Connection to server (input). */
160 static int connection_out;	/* Connection to server (output). */
161 static int need_rekeying;	/* Set to non-zero if rekeying is requested. */
162 static int session_closed;	/* In SSH2: login session closed. */
163 static int x11_refuse_time;	/* If >0, refuse x11 opens after this time. */
164 
165 static void client_init_dispatch(void);
166 int	session_ident = -1;
167 
168 int	session_resumed = 0;
169 
170 /* Track escape per proto2 channel */
171 struct escape_filter_ctx {
172 	int escape_pending;
173 	int escape_char;
174 };
175 
176 /* Context for channel confirmation replies */
177 struct channel_reply_ctx {
178 	const char *request_type;
179 	int id;
180 	enum confirm_action action;
181 };
182 
183 /* Global request success/failure callbacks */
184 struct global_confirm {
185 	TAILQ_ENTRY(global_confirm) entry;
186 	global_confirm_cb *cb;
187 	void *ctx;
188 	int ref_count;
189 };
190 TAILQ_HEAD(global_confirms, global_confirm);
191 static struct global_confirms global_confirms =
192     TAILQ_HEAD_INITIALIZER(global_confirms);
193 
194 /*XXX*/
195 extern Kex *xxx_kex;
196 
197 void ssh_process_session2_setup(int, int, int, Buffer *);
198 
199 /* Restores stdin to blocking mode. */
200 
201 static void
202 leave_non_blocking(void)
203 {
204 	if (in_non_blocking_mode) {
205 		unset_nonblock(fileno(stdin));
206 		in_non_blocking_mode = 0;
207 	}
208 }
209 
210 /* Puts stdin terminal in non-blocking mode. */
211 
212 static void
213 enter_non_blocking(void)
214 {
215 	in_non_blocking_mode = 1;
216 	set_nonblock(fileno(stdin));
217 }
218 
219 /*
220  * Signal handler for the window change signal (SIGWINCH).  This just sets a
221  * flag indicating that the window has changed.
222  */
223 /*ARGSUSED */
224 static void
225 window_change_handler(int sig)
226 {
227 	received_window_change_signal = 1;
228 	signal(SIGWINCH, window_change_handler);
229 }
230 
231 /*
232  * Signal handler for signals that cause the program to terminate.  These
233  * signals must be trapped to restore terminal modes.
234  */
235 /*ARGSUSED */
236 static void
237 signal_handler(int sig)
238 {
239 	received_signal = sig;
240 	quit_pending = 1;
241 }
242 
243 /*
244  * Returns current time in seconds from Jan 1, 1970 with the maximum
245  * available resolution.
246  */
247 
248 static double
249 get_current_time(void)
250 {
251 	struct timeval tv;
252 	gettimeofday(&tv, NULL);
253 	return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
254 }
255 
256 /*
257  * Sets control_persist_exit_time to the absolute time when the
258  * backgrounded control master should exit due to expiry of the
259  * ControlPersist timeout.  Sets it to 0 if we are not a backgrounded
260  * control master process, or if there is no ControlPersist timeout.
261  */
262 static void
263 set_control_persist_exit_time(void)
264 {
265 	if (muxserver_sock == -1 || !options.control_persist
266 	    || options.control_persist_timeout == 0) {
267 		/* not using a ControlPersist timeout */
268 		control_persist_exit_time = 0;
269 	} else if (channel_still_open()) {
270 		/* some client connections are still open */
271 		if (control_persist_exit_time > 0)
272 			debug2("%s: cancel scheduled exit", __func__);
273 		control_persist_exit_time = 0;
274 	} else if (control_persist_exit_time <= 0) {
275 		/* a client connection has recently closed */
276 		control_persist_exit_time = time(NULL) +
277 			(time_t)options.control_persist_timeout;
278 		debug2("%s: schedule exit in %d seconds", __func__,
279 		    options.control_persist_timeout);
280 	}
281 	/* else we are already counting down to the timeout */
282 }
283 
284 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
285 void
286 client_x11_get_proto(const char *display, const char *xauth_path,
287     u_int trusted, u_int timeout, char **_proto, char **_data)
288 {
289 	char cmd[1024];
290 	char line[512];
291 	char xdisplay[512];
292 	static char proto[512], data[512];
293 	FILE *f;
294 	int got_data = 0, generated = 0, do_unlink = 0, i;
295 	char *xauthdir, *xauthfile;
296 	struct stat st;
297 	u_int now;
298 
299 	xauthdir = xauthfile = NULL;
300 	*_proto = proto;
301 	*_data = data;
302 	proto[0] = data[0] = '\0';
303 
304 	if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
305 		debug("No xauth program.");
306 	} else {
307 		if (display == NULL) {
308 			debug("x11_get_proto: DISPLAY not set");
309 			return;
310 		}
311 		/*
312 		 * Handle FamilyLocal case where $DISPLAY does
313 		 * not match an authorization entry.  For this we
314 		 * just try "xauth list unix:displaynum.screennum".
315 		 * XXX: "localhost" match to determine FamilyLocal
316 		 *      is not perfect.
317 		 */
318 		if (strncmp(display, "localhost:", 10) == 0) {
319 			snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
320 			    display + 10);
321 			display = xdisplay;
322 		}
323 		if (trusted == 0) {
324 			xauthdir = xmalloc(MAXPATHLEN);
325 			xauthfile = xmalloc(MAXPATHLEN);
326 			mktemp_proto(xauthdir, MAXPATHLEN);
327 			if (mkdtemp(xauthdir) != NULL) {
328 				do_unlink = 1;
329 				snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
330 				    xauthdir);
331 				snprintf(cmd, sizeof(cmd),
332 				    "%s -f %s generate %s " SSH_X11_PROTO
333 				    " untrusted timeout %u 2>" _PATH_DEVNULL,
334 				    xauth_path, xauthfile, display, timeout);
335 				debug2("x11_get_proto: %s", cmd);
336 				if (system(cmd) == 0)
337 					generated = 1;
338 				if (x11_refuse_time == 0) {
339 					now = time(NULL) + 1;
340 					if (UINT_MAX - timeout < now)
341 						x11_refuse_time = UINT_MAX;
342 					else
343 						x11_refuse_time = now + timeout;
344 				}
345 			}
346 		}
347 
348 		/*
349 		 * When in untrusted mode, we read the cookie only if it was
350 		 * successfully generated as an untrusted one in the step
351 		 * above.
352 		 */
353 		if (trusted || generated) {
354 			snprintf(cmd, sizeof(cmd),
355 			    "%s %s%s list %s 2>" _PATH_DEVNULL,
356 			    xauth_path,
357 			    generated ? "-f " : "" ,
358 			    generated ? xauthfile : "",
359 			    display);
360 			debug2("x11_get_proto: %s", cmd);
361 			f = popen(cmd, "r");
362 			if (f && fgets(line, sizeof(line), f) &&
363 			    sscanf(line, "%*s %511s %511s", proto, data) == 2)
364 				got_data = 1;
365 			if (f)
366 				pclose(f);
367 		} else
368 			error("Warning: untrusted X11 forwarding setup failed: "
369 			    "xauth key data not generated");
370 	}
371 
372 	if (do_unlink) {
373 		unlink(xauthfile);
374 		rmdir(xauthdir);
375 	}
376 	if (xauthdir)
377 		xfree(xauthdir);
378 	if (xauthfile)
379 		xfree(xauthfile);
380 
381 	/*
382 	 * If we didn't get authentication data, just make up some
383 	 * data.  The forwarding code will check the validity of the
384 	 * response anyway, and substitute this data.  The X11
385 	 * server, however, will ignore this fake data and use
386 	 * whatever authentication mechanisms it was using otherwise
387 	 * for the local connection.
388 	 */
389 	if (!got_data) {
390 		u_int32_t rnd = 0;
391 
392 		logit("Warning: No xauth data; "
393 		    "using fake authentication data for X11 forwarding.");
394 		strlcpy(proto, SSH_X11_PROTO, sizeof proto);
395 		for (i = 0; i < 16; i++) {
396 			if (i % 4 == 0)
397 				rnd = arc4random();
398 			snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
399 			    rnd & 0xff);
400 			rnd >>= 8;
401 		}
402 	}
403 }
404 
405 /*
406  * This is called when the interactive is entered.  This checks if there is
407  * an EOF coming on stdin.  We must check this explicitly, as select() does
408  * not appear to wake up when redirecting from /dev/null.
409  */
410 
411 static void
412 client_check_initial_eof_on_stdin(void)
413 {
414 	int len;
415 	char buf[1];
416 
417 	/*
418 	 * If standard input is to be "redirected from /dev/null", we simply
419 	 * mark that we have seen an EOF and send an EOF message to the
420 	 * server. Otherwise, we try to read a single character; it appears
421 	 * that for some files, such /dev/null, select() never wakes up for
422 	 * read for this descriptor, which means that we never get EOF.  This
423 	 * way we will get the EOF if stdin comes from /dev/null or similar.
424 	 */
425 	if (stdin_null_flag) {
426 		/* Fake EOF on stdin. */
427 		debug("Sending eof.");
428 		stdin_eof = 1;
429 		packet_start(SSH_CMSG_EOF);
430 		packet_send();
431 	} else {
432 		enter_non_blocking();
433 
434 		/* Check for immediate EOF on stdin. */
435 		len = read(fileno(stdin), buf, 1);
436 		if (len == 0) {
437 			/*
438 			 * EOF.  Record that we have seen it and send
439 			 * EOF to server.
440 			 */
441 			debug("Sending eof.");
442 			stdin_eof = 1;
443 			packet_start(SSH_CMSG_EOF);
444 			packet_send();
445 		} else if (len > 0) {
446 			/*
447 			 * Got data.  We must store the data in the buffer,
448 			 * and also process it as an escape character if
449 			 * appropriate.
450 			 */
451 			if ((u_char) buf[0] == escape_char1)
452 				escape_pending1 = 1;
453 			else
454 				buffer_append(&stdin_buffer, buf, 1);
455 		}
456 		leave_non_blocking();
457 	}
458 }
459 
460 
461 /*
462  * Make packets from buffered stdin data, and buffer them for sending to the
463  * connection.
464  */
465 
466 static void
467 client_make_packets_from_stdin_data(void)
468 {
469 	u_int len;
470 
471 	/* Send buffered stdin data to the server. */
472 	while (buffer_len(&stdin_buffer) > 0 &&
473 	    packet_not_very_much_data_to_write()) {
474 		len = buffer_len(&stdin_buffer);
475 		/* Keep the packets at reasonable size. */
476 		if (len > packet_get_maxsize())
477 			len = packet_get_maxsize();
478 		packet_start(SSH_CMSG_STDIN_DATA);
479 		packet_put_string(buffer_ptr(&stdin_buffer), len);
480 		packet_send();
481 		buffer_consume(&stdin_buffer, len);
482 		/* If we have a pending EOF, send it now. */
483 		if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
484 			packet_start(SSH_CMSG_EOF);
485 			packet_send();
486 		}
487 	}
488 }
489 
490 /*
491  * Checks if the client window has changed, and sends a packet about it to
492  * the server if so.  The actual change is detected elsewhere (by a software
493  * interrupt on Unix); this just checks the flag and sends a message if
494  * appropriate.
495  */
496 
497 static void
498 client_check_window_change(void)
499 {
500 	struct winsize ws;
501 
502 	if (! received_window_change_signal)
503 		return;
504 	/** XXX race */
505 	received_window_change_signal = 0;
506 
507 	debug2("client_check_window_change: changed");
508 
509 	if (compat20) {
510 		channel_send_window_changes();
511 	} else {
512 		if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
513 			return;
514 		packet_start(SSH_CMSG_WINDOW_SIZE);
515 		packet_put_int((u_int)ws.ws_row);
516 		packet_put_int((u_int)ws.ws_col);
517 		packet_put_int((u_int)ws.ws_xpixel);
518 		packet_put_int((u_int)ws.ws_ypixel);
519 		packet_send();
520 	}
521 }
522 
523 static void
524 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
525 {
526 	struct global_confirm *gc;
527 
528 	if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
529 		return;
530 	if (gc->cb != NULL)
531 		gc->cb(type, seq, gc->ctx);
532 	if (--gc->ref_count <= 0) {
533 		TAILQ_REMOVE(&global_confirms, gc, entry);
534 		bzero(gc, sizeof(*gc));
535 		xfree(gc);
536 	}
537 
538 	packet_set_alive_timeouts(0);
539 }
540 
541 static void
542 server_alive_check(void)
543 {
544 	if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
545 		logit("Timeout, server %s not responding.", host);
546 		cleanup_exit(255);
547 	}
548 	packet_start(SSH2_MSG_GLOBAL_REQUEST);
549 	packet_put_cstring("keepalive@openssh.com");
550 	packet_put_char(1);     /* boolean: want reply */
551 	packet_send();
552 	/* Insert an empty placeholder to maintain ordering */
553 	client_register_global_confirm(NULL, NULL);
554 }
555 
556 /*
557  * Waits until the client can do something (some data becomes available on
558  * one of the file descriptors).
559  */
560 static void
561 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
562     int *maxfdp, u_int *nallocp, int rekeying)
563 {
564 	struct timeval tv, *tvp;
565 	int timeout_secs;
566 	int ret;
567 
568 	/* Add any selections by the channel mechanism. */
569 	channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
570 
571 	if (!compat20) {
572 		/* Read from the connection, unless our buffers are full. */
573 		if (buffer_len(&stdout_buffer) < buffer_high &&
574 		    buffer_len(&stderr_buffer) < buffer_high &&
575 		    channel_not_very_much_buffered_data())
576 			FD_SET(connection_in, *readsetp);
577 		/*
578 		 * Read from stdin, unless we have seen EOF or have very much
579 		 * buffered data to send to the server.
580 		 */
581 		if (!stdin_eof && packet_not_very_much_data_to_write())
582 			FD_SET(fileno(stdin), *readsetp);
583 
584 		/* Select stdout/stderr if have data in buffer. */
585 		if (buffer_len(&stdout_buffer) > 0)
586 			FD_SET(fileno(stdout), *writesetp);
587 		if (buffer_len(&stderr_buffer) > 0)
588 			FD_SET(fileno(stderr), *writesetp);
589 	} else {
590 		/* channel_prepare_select could have closed the last channel */
591 		if (session_closed && !channel_still_open() &&
592 		    !packet_have_data_to_write()) {
593 			/* clear mask since we did not call select() */
594 			memset(*readsetp, 0, *nallocp);
595 			memset(*writesetp, 0, *nallocp);
596 			return;
597 		} else {
598 			FD_SET(connection_in, *readsetp);
599 		}
600 	}
601 
602 	/* Select server connection if have data to write to the server. */
603 	if (packet_have_data_to_write())
604 		FD_SET(connection_out, *writesetp);
605 
606 	/*
607 	 * Wait for something to happen.  This will suspend the process until
608 	 * some selected descriptor can be read, written, or has some other
609 	 * event pending, or a timeout expires.
610 	 */
611 
612 	timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
613 	if (options.server_alive_interval > 0 && compat20)
614 		timeout_secs = options.server_alive_interval;
615 	set_control_persist_exit_time();
616 	if (control_persist_exit_time > 0) {
617 		timeout_secs = MIN(timeout_secs,
618 			control_persist_exit_time - time(NULL));
619 		if (timeout_secs < 0)
620 			timeout_secs = 0;
621 	}
622 	if (timeout_secs == INT_MAX)
623 		tvp = NULL;
624 	else {
625 		tv.tv_sec = timeout_secs;
626 		tv.tv_usec = 0;
627 		tvp = &tv;
628 	}
629 
630 	ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
631 	if (ret < 0) {
632 		char buf[100];
633 
634 		/*
635 		 * We have to clear the select masks, because we return.
636 		 * We have to return, because the mainloop checks for the flags
637 		 * set by the signal handlers.
638 		 */
639 		memset(*readsetp, 0, *nallocp);
640 		memset(*writesetp, 0, *nallocp);
641 
642 		if (errno == EINTR)
643 			return;
644 		/* Note: we might still have data in the buffers. */
645 		snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
646 		buffer_append(&stderr_buffer, buf, strlen(buf));
647 		quit_pending = 1;
648 	} else if (ret == 0)
649 		server_alive_check();
650 }
651 
652 static void
653 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
654 {
655 	/* Flush stdout and stderr buffers. */
656 	if (buffer_len(bout) > 0)
657 		atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
658 		    buffer_len(bout));
659 	if (buffer_len(berr) > 0)
660 		atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
661 		    buffer_len(berr));
662 
663 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
664 
665 	/*
666 	 * Free (and clear) the buffer to reduce the amount of data that gets
667 	 * written to swap.
668 	 */
669 	buffer_free(bin);
670 	buffer_free(bout);
671 	buffer_free(berr);
672 
673 	/* Send the suspend signal to the program itself. */
674 	kill(getpid(), SIGTSTP);
675 
676 	/* Reset window sizes in case they have changed */
677 	received_window_change_signal = 1;
678 
679 	/* OK, we have been continued by the user. Reinitialize buffers. */
680 	buffer_init(bin);
681 	buffer_init(bout);
682 	buffer_init(berr);
683 
684 	enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
685 }
686 
687 static void
688 client_process_net_input(fd_set *readset)
689 {
690 	int len, cont = 0;
691 	char buf[SSH_IOBUFSZ];
692 
693 	/*
694 	 * Read input from the server, and add any such data to the buffer of
695 	 * the packet subsystem.
696 	 */
697 	if (FD_ISSET(connection_in, readset)) {
698 		/* Read as much as possible. */
699 		len = roaming_read(connection_in, buf, sizeof(buf), &cont);
700 		if (len == 0 && cont == 0) {
701 			/*
702 			 * Received EOF.  The remote host has closed the
703 			 * connection.
704 			 */
705 			snprintf(buf, sizeof buf,
706 			    "Connection to %.300s closed by remote host.\r\n",
707 			    host);
708 			buffer_append(&stderr_buffer, buf, strlen(buf));
709 			quit_pending = 1;
710 			return;
711 		}
712 		/*
713 		 * There is a kernel bug on Solaris that causes select to
714 		 * sometimes wake up even though there is no data available.
715 		 */
716 		if (len < 0 &&
717 		    (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
718 			len = 0;
719 
720 		if (len < 0) {
721 			/*
722 			 * An error has encountered.  Perhaps there is a
723 			 * network problem.
724 			 */
725 			snprintf(buf, sizeof buf,
726 			    "Read from remote host %.300s: %.100s\r\n",
727 			    host, strerror(errno));
728 			buffer_append(&stderr_buffer, buf, strlen(buf));
729 			quit_pending = 1;
730 			return;
731 		}
732 		packet_process_incoming(buf, len);
733 	}
734 }
735 
736 static void
737 client_status_confirm(int type, Channel *c, void *ctx)
738 {
739 	struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
740 	char errmsg[256];
741 	int tochan;
742 
743 	/*
744 	 * If a TTY was explicitly requested, then a failure to allocate
745 	 * one is fatal.
746 	 */
747 	if (cr->action == CONFIRM_TTY &&
748 	    (options.request_tty == REQUEST_TTY_FORCE ||
749 	    options.request_tty == REQUEST_TTY_YES))
750 		cr->action = CONFIRM_CLOSE;
751 
752 	/* XXX supress on mux _client_ quietmode */
753 	tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
754 	    c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
755 
756 	if (type == SSH2_MSG_CHANNEL_SUCCESS) {
757 		debug2("%s request accepted on channel %d",
758 		    cr->request_type, c->self);
759 	} else if (type == SSH2_MSG_CHANNEL_FAILURE) {
760 		if (tochan) {
761 			snprintf(errmsg, sizeof(errmsg),
762 			    "%s request failed\r\n", cr->request_type);
763 		} else {
764 			snprintf(errmsg, sizeof(errmsg),
765 			    "%s request failed on channel %d",
766 			    cr->request_type, c->self);
767 		}
768 		/* If error occurred on primary session channel, then exit */
769 		if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
770 			fatal("%s", errmsg);
771 		/*
772 		 * If error occurred on mux client, append to
773 		 * their stderr.
774 		 */
775 		if (tochan) {
776 			buffer_append(&c->extended, errmsg,
777 			    strlen(errmsg));
778 		} else
779 			error("%s", errmsg);
780 		if (cr->action == CONFIRM_TTY) {
781 			/*
782 			 * If a TTY allocation error occurred, then arrange
783 			 * for the correct TTY to leave raw mode.
784 			 */
785 			if (c->self == session_ident)
786 				leave_raw_mode(0);
787 			else
788 				mux_tty_alloc_failed(c);
789 		} else if (cr->action == CONFIRM_CLOSE) {
790 			chan_read_failed(c);
791 			chan_write_failed(c);
792 		}
793 	}
794 	xfree(cr);
795 }
796 
797 static void
798 client_abandon_status_confirm(Channel *c, void *ctx)
799 {
800 	xfree(ctx);
801 }
802 
803 void
804 client_expect_confirm(int id, const char *request,
805     enum confirm_action action)
806 {
807 	struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
808 
809 	cr->request_type = request;
810 	cr->action = action;
811 
812 	channel_register_status_confirm(id, client_status_confirm,
813 	    client_abandon_status_confirm, cr);
814 }
815 
816 void
817 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
818 {
819 	struct global_confirm *gc, *last_gc;
820 
821 	/* Coalesce identical callbacks */
822 	last_gc = TAILQ_LAST(&global_confirms, global_confirms);
823 	if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
824 		if (++last_gc->ref_count >= INT_MAX)
825 			fatal("%s: last_gc->ref_count = %d",
826 			    __func__, last_gc->ref_count);
827 		return;
828 	}
829 
830 	gc = xmalloc(sizeof(*gc));
831 	gc->cb = cb;
832 	gc->ctx = ctx;
833 	gc->ref_count = 1;
834 	TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
835 }
836 
837 static void
838 process_cmdline(void)
839 {
840 	void (*handler)(int);
841 	char *s, *cmd, *cancel_host;
842 	int delete = 0;
843 	int local = 0, remote = 0, dynamic = 0;
844 	int cancel_port;
845 	Forward fwd;
846 
847 	bzero(&fwd, sizeof(fwd));
848 	fwd.listen_host = fwd.connect_host = NULL;
849 
850 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
851 	handler = signal(SIGINT, SIG_IGN);
852 	cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
853 	if (s == NULL)
854 		goto out;
855 	while (isspace(*s))
856 		s++;
857 	if (*s == '-')
858 		s++;	/* Skip cmdline '-', if any */
859 	if (*s == '\0')
860 		goto out;
861 
862 	if (*s == 'h' || *s == 'H' || *s == '?') {
863 		logit("Commands:");
864 		logit("      -L[bind_address:]port:host:hostport    "
865 		    "Request local forward");
866 		logit("      -R[bind_address:]port:host:hostport    "
867 		    "Request remote forward");
868 		logit("      -D[bind_address:]port                  "
869 		    "Request dynamic forward");
870 		logit("      -KR[bind_address:]port                 "
871 		    "Cancel remote forward");
872 		if (!options.permit_local_command)
873 			goto out;
874 		logit("      !args                                  "
875 		    "Execute local command");
876 		goto out;
877 	}
878 
879 	if (*s == '!' && options.permit_local_command) {
880 		s++;
881 		ssh_local_cmd(s);
882 		goto out;
883 	}
884 
885 	if (*s == 'K') {
886 		delete = 1;
887 		s++;
888 	}
889 	if (*s == 'L')
890 		local = 1;
891 	else if (*s == 'R')
892 		remote = 1;
893 	else if (*s == 'D')
894 		dynamic = 1;
895 	else {
896 		logit("Invalid command.");
897 		goto out;
898 	}
899 
900 	if ((local || dynamic) && delete) {
901 		logit("Not supported.");
902 		goto out;
903 	}
904 	if (remote && delete && !compat20) {
905 		logit("Not supported for SSH protocol version 1.");
906 		goto out;
907 	}
908 
909 	while (isspace(*++s))
910 		;
911 
912 	/* XXX update list of forwards in options */
913 	if (delete) {
914 		cancel_port = 0;
915 		cancel_host = hpdelim(&s);	/* may be NULL */
916 		if (s != NULL) {
917 			cancel_port = a2port(s);
918 			cancel_host = cleanhostname(cancel_host);
919 		} else {
920 			cancel_port = a2port(cancel_host);
921 			cancel_host = NULL;
922 		}
923 		if (cancel_port <= 0) {
924 			logit("Bad forwarding close port");
925 			goto out;
926 		}
927 		channel_request_rforward_cancel(cancel_host, cancel_port);
928 	} else {
929 		if (!parse_forward(&fwd, s, dynamic, remote)) {
930 			logit("Bad forwarding specification.");
931 			goto out;
932 		}
933 		if (local || dynamic) {
934 			if (channel_setup_local_fwd_listener(fwd.listen_host,
935 			    fwd.listen_port, fwd.connect_host,
936 			    fwd.connect_port, options.gateway_ports) < 0) {
937 				logit("Port forwarding failed.");
938 				goto out;
939 			}
940 		} else {
941 			if (channel_request_remote_forwarding(fwd.listen_host,
942 			    fwd.listen_port, fwd.connect_host,
943 			    fwd.connect_port) < 0) {
944 				logit("Port forwarding failed.");
945 				goto out;
946 			}
947 		}
948 
949 		logit("Forwarding port.");
950 	}
951 
952 out:
953 	signal(SIGINT, handler);
954 	enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
955 	if (cmd)
956 		xfree(cmd);
957 	if (fwd.listen_host != NULL)
958 		xfree(fwd.listen_host);
959 	if (fwd.connect_host != NULL)
960 		xfree(fwd.connect_host);
961 }
962 
963 /*
964  * Process the characters one by one, call with c==NULL for proto1 case.
965  */
966 static int
967 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
968     char *buf, int len)
969 {
970 	char string[1024];
971 	pid_t pid;
972 	int bytes = 0;
973 	u_int i;
974 	u_char ch;
975 	char *s;
976 	int *escape_pendingp, escape_char;
977 	struct escape_filter_ctx *efc;
978 
979 	if (c == NULL) {
980 		escape_pendingp = &escape_pending1;
981 		escape_char = escape_char1;
982 	} else {
983 		if (c->filter_ctx == NULL)
984 			return 0;
985 		efc = (struct escape_filter_ctx *)c->filter_ctx;
986 		escape_pendingp = &efc->escape_pending;
987 		escape_char = efc->escape_char;
988 	}
989 
990 	if (len <= 0)
991 		return (0);
992 
993 	for (i = 0; i < (u_int)len; i++) {
994 		/* Get one character at a time. */
995 		ch = buf[i];
996 
997 		if (*escape_pendingp) {
998 			/* We have previously seen an escape character. */
999 			/* Clear the flag now. */
1000 			*escape_pendingp = 0;
1001 
1002 			/* Process the escaped character. */
1003 			switch (ch) {
1004 			case '.':
1005 				/* Terminate the connection. */
1006 				snprintf(string, sizeof string, "%c.\r\n",
1007 				    escape_char);
1008 				buffer_append(berr, string, strlen(string));
1009 
1010 				if (c && c->ctl_chan != -1) {
1011 					chan_read_failed(c);
1012 					chan_write_failed(c);
1013 					return 0;
1014 				} else
1015 					quit_pending = 1;
1016 				return -1;
1017 
1018 			case 'Z' - 64:
1019 				/* XXX support this for mux clients */
1020 				if (c && c->ctl_chan != -1) {
1021  noescape:
1022 					snprintf(string, sizeof string,
1023 					    "%c%c escape not available to "
1024 					    "multiplexed sessions\r\n",
1025 					    escape_char, ch);
1026 					buffer_append(berr, string,
1027 					    strlen(string));
1028 					continue;
1029 				}
1030 				/* Suspend the program. Inform the user */
1031 				snprintf(string, sizeof string,
1032 				    "%c^Z [suspend ssh]\r\n", escape_char);
1033 				buffer_append(berr, string, strlen(string));
1034 
1035 				/* Restore terminal modes and suspend. */
1036 				client_suspend_self(bin, bout, berr);
1037 
1038 				/* We have been continued. */
1039 				continue;
1040 
1041 			case 'B':
1042 				if (compat20) {
1043 					snprintf(string, sizeof string,
1044 					    "%cB\r\n", escape_char);
1045 					buffer_append(berr, string,
1046 					    strlen(string));
1047 					channel_request_start(session_ident,
1048 					    "break", 0);
1049 					packet_put_int(1000);
1050 					packet_send();
1051 				}
1052 				continue;
1053 
1054 			case 'R':
1055 				if (compat20) {
1056 					if (datafellows & SSH_BUG_NOREKEY)
1057 						logit("Server does not "
1058 						    "support re-keying");
1059 					else
1060 						need_rekeying = 1;
1061 				}
1062 				continue;
1063 
1064 			case '&':
1065 				if (c && c->ctl_chan != -1)
1066 					goto noescape;
1067 				/*
1068 				 * Detach the program (continue to serve
1069 				 * connections, but put in background and no
1070 				 * more new connections).
1071 				 */
1072 				/* Restore tty modes. */
1073 				leave_raw_mode(
1074 				    options.request_tty == REQUEST_TTY_FORCE);
1075 
1076 				/* Stop listening for new connections. */
1077 				channel_stop_listening();
1078 
1079 				snprintf(string, sizeof string,
1080 				    "%c& [backgrounded]\n", escape_char);
1081 				buffer_append(berr, string, strlen(string));
1082 
1083 				/* Fork into background. */
1084 				pid = fork();
1085 				if (pid < 0) {
1086 					error("fork: %.100s", strerror(errno));
1087 					continue;
1088 				}
1089 				if (pid != 0) {	/* This is the parent. */
1090 					/* The parent just exits. */
1091 					exit(0);
1092 				}
1093 				/* The child continues serving connections. */
1094 				if (compat20) {
1095 					buffer_append(bin, "\004", 1);
1096 					/* fake EOF on stdin */
1097 					return -1;
1098 				} else if (!stdin_eof) {
1099 					/*
1100 					 * Sending SSH_CMSG_EOF alone does not
1101 					 * always appear to be enough.  So we
1102 					 * try to send an EOF character first.
1103 					 */
1104 					packet_start(SSH_CMSG_STDIN_DATA);
1105 					packet_put_string("\004", 1);
1106 					packet_send();
1107 					/* Close stdin. */
1108 					stdin_eof = 1;
1109 					if (buffer_len(bin) == 0) {
1110 						packet_start(SSH_CMSG_EOF);
1111 						packet_send();
1112 					}
1113 				}
1114 				continue;
1115 
1116 			case '?':
1117 				if (c && c->ctl_chan != -1) {
1118 					snprintf(string, sizeof string,
1119 "%c?\r\n\
1120 Supported escape sequences:\r\n\
1121   %c.  - terminate session\r\n\
1122   %cB  - send a BREAK to the remote system\r\n\
1123   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1124   %c#  - list forwarded connections\r\n\
1125   %c?  - this message\r\n\
1126   %c%c  - send the escape character by typing it twice\r\n\
1127 (Note that escapes are only recognized immediately after newline.)\r\n",
1128 					    escape_char, escape_char,
1129 					    escape_char, escape_char,
1130 					    escape_char, escape_char,
1131 					    escape_char, escape_char);
1132 				} else {
1133 					snprintf(string, sizeof string,
1134 "%c?\r\n\
1135 Supported escape sequences:\r\n\
1136   %c.  - terminate connection (and any multiplexed sessions)\r\n\
1137   %cB  - send a BREAK to the remote system\r\n\
1138   %cC  - open a command line\r\n\
1139   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1140   %c^Z - suspend ssh\r\n\
1141   %c#  - list forwarded connections\r\n\
1142   %c&  - background ssh (when waiting for connections to terminate)\r\n\
1143   %c?  - this message\r\n\
1144   %c%c  - send the escape character by typing it twice\r\n\
1145 (Note that escapes are only recognized immediately after newline.)\r\n",
1146 					    escape_char, escape_char,
1147 					    escape_char, escape_char,
1148 					    escape_char, escape_char,
1149 					    escape_char, escape_char,
1150 					    escape_char, escape_char,
1151 					    escape_char);
1152 				}
1153 				buffer_append(berr, string, strlen(string));
1154 				continue;
1155 
1156 			case '#':
1157 				snprintf(string, sizeof string, "%c#\r\n",
1158 				    escape_char);
1159 				buffer_append(berr, string, strlen(string));
1160 				s = channel_open_message();
1161 				buffer_append(berr, s, strlen(s));
1162 				xfree(s);
1163 				continue;
1164 
1165 			case 'C':
1166 				if (c && c->ctl_chan != -1)
1167 					goto noescape;
1168 				process_cmdline();
1169 				continue;
1170 
1171 			default:
1172 				if (ch != escape_char) {
1173 					buffer_put_char(bin, escape_char);
1174 					bytes++;
1175 				}
1176 				/* Escaped characters fall through here */
1177 				break;
1178 			}
1179 		} else {
1180 			/*
1181 			 * The previous character was not an escape char.
1182 			 * Check if this is an escape.
1183 			 */
1184 			if (last_was_cr && ch == escape_char) {
1185 				/*
1186 				 * It is. Set the flag and continue to
1187 				 * next character.
1188 				 */
1189 				*escape_pendingp = 1;
1190 				continue;
1191 			}
1192 		}
1193 
1194 		/*
1195 		 * Normal character.  Record whether it was a newline,
1196 		 * and append it to the buffer.
1197 		 */
1198 		last_was_cr = (ch == '\r' || ch == '\n');
1199 		buffer_put_char(bin, ch);
1200 		bytes++;
1201 	}
1202 	return bytes;
1203 }
1204 
1205 static void
1206 client_process_input(fd_set *readset)
1207 {
1208 	int len;
1209 	char buf[SSH_IOBUFSZ];
1210 
1211 	/* Read input from stdin. */
1212 	if (FD_ISSET(fileno(stdin), readset)) {
1213 		/* Read as much as possible. */
1214 		len = read(fileno(stdin), buf, sizeof(buf));
1215 		if (len < 0 &&
1216 		    (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1217 			return;		/* we'll try again later */
1218 		if (len <= 0) {
1219 			/*
1220 			 * Received EOF or error.  They are treated
1221 			 * similarly, except that an error message is printed
1222 			 * if it was an error condition.
1223 			 */
1224 			if (len < 0) {
1225 				snprintf(buf, sizeof buf, "read: %.100s\r\n",
1226 				    strerror(errno));
1227 				buffer_append(&stderr_buffer, buf, strlen(buf));
1228 			}
1229 			/* Mark that we have seen EOF. */
1230 			stdin_eof = 1;
1231 			/*
1232 			 * Send an EOF message to the server unless there is
1233 			 * data in the buffer.  If there is data in the
1234 			 * buffer, no message will be sent now.  Code
1235 			 * elsewhere will send the EOF when the buffer
1236 			 * becomes empty if stdin_eof is set.
1237 			 */
1238 			if (buffer_len(&stdin_buffer) == 0) {
1239 				packet_start(SSH_CMSG_EOF);
1240 				packet_send();
1241 			}
1242 		} else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1243 			/*
1244 			 * Normal successful read, and no escape character.
1245 			 * Just append the data to buffer.
1246 			 */
1247 			buffer_append(&stdin_buffer, buf, len);
1248 		} else {
1249 			/*
1250 			 * Normal, successful read.  But we have an escape
1251 			 * character and have to process the characters one
1252 			 * by one.
1253 			 */
1254 			if (process_escapes(NULL, &stdin_buffer,
1255 			    &stdout_buffer, &stderr_buffer, buf, len) == -1)
1256 				return;
1257 		}
1258 	}
1259 }
1260 
1261 static void
1262 client_process_output(fd_set *writeset)
1263 {
1264 	int len;
1265 	char buf[100];
1266 
1267 	/* Write buffered output to stdout. */
1268 	if (FD_ISSET(fileno(stdout), writeset)) {
1269 		/* Write as much data as possible. */
1270 		len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1271 		    buffer_len(&stdout_buffer));
1272 		if (len <= 0) {
1273 			if (errno == EINTR || errno == EAGAIN ||
1274 			    errno == EWOULDBLOCK)
1275 				len = 0;
1276 			else {
1277 				/*
1278 				 * An error or EOF was encountered.  Put an
1279 				 * error message to stderr buffer.
1280 				 */
1281 				snprintf(buf, sizeof buf,
1282 				    "write stdout: %.50s\r\n", strerror(errno));
1283 				buffer_append(&stderr_buffer, buf, strlen(buf));
1284 				quit_pending = 1;
1285 				return;
1286 			}
1287 		}
1288 		/* Consume printed data from the buffer. */
1289 		buffer_consume(&stdout_buffer, len);
1290 	}
1291 	/* Write buffered output to stderr. */
1292 	if (FD_ISSET(fileno(stderr), writeset)) {
1293 		/* Write as much data as possible. */
1294 		len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1295 		    buffer_len(&stderr_buffer));
1296 		if (len <= 0) {
1297 			if (errno == EINTR || errno == EAGAIN ||
1298 			    errno == EWOULDBLOCK)
1299 				len = 0;
1300 			else {
1301 				/*
1302 				 * EOF or error, but can't even print
1303 				 * error message.
1304 				 */
1305 				quit_pending = 1;
1306 				return;
1307 			}
1308 		}
1309 		/* Consume printed characters from the buffer. */
1310 		buffer_consume(&stderr_buffer, len);
1311 	}
1312 }
1313 
1314 /*
1315  * Get packets from the connection input buffer, and process them as long as
1316  * there are packets available.
1317  *
1318  * Any unknown packets received during the actual
1319  * session cause the session to terminate.  This is
1320  * intended to make debugging easier since no
1321  * confirmations are sent.  Any compatible protocol
1322  * extensions must be negotiated during the
1323  * preparatory phase.
1324  */
1325 
1326 static void
1327 client_process_buffered_input_packets(void)
1328 {
1329 	dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1330 	    compat20 ? xxx_kex : NULL);
1331 }
1332 
1333 /* scan buf[] for '~' before sending data to the peer */
1334 
1335 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1336 void *
1337 client_new_escape_filter_ctx(int escape_char)
1338 {
1339 	struct escape_filter_ctx *ret;
1340 
1341 	ret = xmalloc(sizeof(*ret));
1342 	ret->escape_pending = 0;
1343 	ret->escape_char = escape_char;
1344 	return (void *)ret;
1345 }
1346 
1347 /* Free the escape filter context on channel free */
1348 void
1349 client_filter_cleanup(int cid, void *ctx)
1350 {
1351 	xfree(ctx);
1352 }
1353 
1354 int
1355 client_simple_escape_filter(Channel *c, char *buf, int len)
1356 {
1357 	if (c->extended_usage != CHAN_EXTENDED_WRITE)
1358 		return 0;
1359 
1360 	return process_escapes(c, &c->input, &c->output, &c->extended,
1361 	    buf, len);
1362 }
1363 
1364 static void
1365 client_channel_closed(int id, void *arg)
1366 {
1367 	channel_cancel_cleanup(id);
1368 	session_closed = 1;
1369 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1370 }
1371 
1372 /*
1373  * Implements the interactive session with the server.  This is called after
1374  * the user has been authenticated, and a command has been started on the
1375  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1376  * used as an escape character for terminating or suspending the session.
1377  */
1378 
1379 int
1380 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1381 {
1382 	fd_set *readset = NULL, *writeset = NULL;
1383 	double start_time, total_time;
1384 	int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1385 	u_int64_t ibytes, obytes;
1386 	u_int nalloc = 0;
1387 	char buf[100];
1388 
1389 	debug("Entering interactive session.");
1390 
1391 	start_time = get_current_time();
1392 
1393 	/* Initialize variables. */
1394 	escape_pending1 = 0;
1395 	last_was_cr = 1;
1396 	exit_status = -1;
1397 	stdin_eof = 0;
1398 	buffer_high = 64 * 1024;
1399 	connection_in = packet_get_connection_in();
1400 	connection_out = packet_get_connection_out();
1401 	max_fd = MAX(connection_in, connection_out);
1402 
1403 	if (!compat20) {
1404 		/* enable nonblocking unless tty */
1405 		if (!isatty(fileno(stdin)))
1406 			set_nonblock(fileno(stdin));
1407 		if (!isatty(fileno(stdout)))
1408 			set_nonblock(fileno(stdout));
1409 		if (!isatty(fileno(stderr)))
1410 			set_nonblock(fileno(stderr));
1411 		max_fd = MAX(max_fd, fileno(stdin));
1412 		max_fd = MAX(max_fd, fileno(stdout));
1413 		max_fd = MAX(max_fd, fileno(stderr));
1414 	}
1415 	quit_pending = 0;
1416 	escape_char1 = escape_char_arg;
1417 
1418 	/* Initialize buffers. */
1419 	buffer_init(&stdin_buffer);
1420 	buffer_init(&stdout_buffer);
1421 	buffer_init(&stderr_buffer);
1422 
1423 	client_init_dispatch();
1424 
1425 	/*
1426 	 * Set signal handlers, (e.g. to restore non-blocking mode)
1427 	 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1428 	 */
1429 	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1430 		signal(SIGHUP, signal_handler);
1431 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1432 		signal(SIGINT, signal_handler);
1433 	if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1434 		signal(SIGQUIT, signal_handler);
1435 	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1436 		signal(SIGTERM, signal_handler);
1437 	signal(SIGWINCH, window_change_handler);
1438 
1439 	if (have_pty)
1440 		enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1441 
1442 	if (compat20) {
1443 		session_ident = ssh2_chan_id;
1444 		if (session_ident != -1) {
1445 			if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1446 				channel_register_filter(session_ident,
1447 				    client_simple_escape_filter, NULL,
1448 				    client_filter_cleanup,
1449 				    client_new_escape_filter_ctx(
1450 				    escape_char_arg));
1451 			}
1452 			channel_register_cleanup(session_ident,
1453 			    client_channel_closed, 0);
1454 		}
1455 	} else {
1456 		/* Check if we should immediately send eof on stdin. */
1457 		client_check_initial_eof_on_stdin();
1458 	}
1459 
1460 	/* Main loop of the client for the interactive session mode. */
1461 	while (!quit_pending) {
1462 
1463 		/* Process buffered packets sent by the server. */
1464 		client_process_buffered_input_packets();
1465 
1466 		if (compat20 && session_closed && !channel_still_open())
1467 			break;
1468 
1469 		rekeying = (xxx_kex != NULL && !xxx_kex->done);
1470 
1471 		if (rekeying) {
1472 			debug("rekeying in progress");
1473 		} else {
1474 			/*
1475 			 * Make packets of buffered stdin data, and buffer
1476 			 * them for sending to the server.
1477 			 */
1478 			if (!compat20)
1479 				client_make_packets_from_stdin_data();
1480 
1481 			/*
1482 			 * Make packets from buffered channel data, and
1483 			 * enqueue them for sending to the server.
1484 			 */
1485 			if (packet_not_very_much_data_to_write())
1486 				channel_output_poll();
1487 
1488 			/*
1489 			 * Check if the window size has changed, and buffer a
1490 			 * message about it to the server if so.
1491 			 */
1492 			client_check_window_change();
1493 
1494 			if (quit_pending)
1495 				break;
1496 		}
1497 		/*
1498 		 * Wait until we have something to do (something becomes
1499 		 * available on one of the descriptors).
1500 		 */
1501 		max_fd2 = max_fd;
1502 		client_wait_until_can_do_something(&readset, &writeset,
1503 		    &max_fd2, &nalloc, rekeying);
1504 
1505 		if (quit_pending)
1506 			break;
1507 
1508 		/* Do channel operations unless rekeying in progress. */
1509 		if (!rekeying) {
1510 			channel_after_select(readset, writeset);
1511 			if (need_rekeying || packet_need_rekeying()) {
1512 				debug("need rekeying");
1513 				xxx_kex->done = 0;
1514 				kex_send_kexinit(xxx_kex);
1515 				need_rekeying = 0;
1516 			}
1517 		}
1518 
1519 		/* Buffer input from the connection.  */
1520 		client_process_net_input(readset);
1521 
1522 		if (quit_pending)
1523 			break;
1524 
1525 		if (!compat20) {
1526 			/* Buffer data from stdin */
1527 			client_process_input(readset);
1528 			/*
1529 			 * Process output to stdout and stderr.  Output to
1530 			 * the connection is processed elsewhere (above).
1531 			 */
1532 			client_process_output(writeset);
1533 		}
1534 
1535 		if (session_resumed) {
1536 			connection_in = packet_get_connection_in();
1537 			connection_out = packet_get_connection_out();
1538 			max_fd = MAX(max_fd, connection_out);
1539 			max_fd = MAX(max_fd, connection_in);
1540 			session_resumed = 0;
1541 		}
1542 
1543 		/*
1544 		 * Send as much buffered packet data as possible to the
1545 		 * sender.
1546 		 */
1547 		if (FD_ISSET(connection_out, writeset))
1548 			packet_write_poll();
1549 
1550 		/*
1551 		 * If we are a backgrounded control master, and the
1552 		 * timeout has expired without any active client
1553 		 * connections, then quit.
1554 		 */
1555 		if (control_persist_exit_time > 0) {
1556 			if (time(NULL) >= control_persist_exit_time) {
1557 				debug("ControlPersist timeout expired");
1558 				break;
1559 			}
1560 		}
1561 	}
1562 	if (readset)
1563 		xfree(readset);
1564 	if (writeset)
1565 		xfree(writeset);
1566 
1567 	/* Terminate the session. */
1568 
1569 	/* Stop watching for window change. */
1570 	signal(SIGWINCH, SIG_DFL);
1571 
1572 	if (compat20) {
1573 		packet_start(SSH2_MSG_DISCONNECT);
1574 		packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1575 		packet_put_cstring("disconnected by user");
1576 		packet_put_cstring(""); /* language tag */
1577 		packet_send();
1578 		packet_write_wait();
1579 	}
1580 
1581 	channel_free_all();
1582 
1583 	if (have_pty)
1584 		leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1585 
1586 	/* restore blocking io */
1587 	if (!isatty(fileno(stdin)))
1588 		unset_nonblock(fileno(stdin));
1589 	if (!isatty(fileno(stdout)))
1590 		unset_nonblock(fileno(stdout));
1591 	if (!isatty(fileno(stderr)))
1592 		unset_nonblock(fileno(stderr));
1593 
1594 	/*
1595 	 * If there was no shell or command requested, there will be no remote
1596 	 * exit status to be returned.  In that case, clear error code if the
1597 	 * connection was deliberately terminated at this end.
1598 	 */
1599 	if (no_shell_flag && received_signal == SIGTERM) {
1600 		received_signal = 0;
1601 		exit_status = 0;
1602 	}
1603 
1604 	if (received_signal)
1605 		fatal("Killed by signal %d.", (int) received_signal);
1606 
1607 	/*
1608 	 * In interactive mode (with pseudo tty) display a message indicating
1609 	 * that the connection has been closed.
1610 	 */
1611 	if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1612 		snprintf(buf, sizeof buf,
1613 		    "Connection to %.64s closed.\r\n", host);
1614 		buffer_append(&stderr_buffer, buf, strlen(buf));
1615 	}
1616 
1617 	/* Output any buffered data for stdout. */
1618 	if (buffer_len(&stdout_buffer) > 0) {
1619 		len = atomicio(vwrite, fileno(stdout),
1620 		    buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1621 		if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1622 			error("Write failed flushing stdout buffer.");
1623 		else
1624 			buffer_consume(&stdout_buffer, len);
1625 	}
1626 
1627 	/* Output any buffered data for stderr. */
1628 	if (buffer_len(&stderr_buffer) > 0) {
1629 		len = atomicio(vwrite, fileno(stderr),
1630 		    buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1631 		if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1632 			error("Write failed flushing stderr buffer.");
1633 		else
1634 			buffer_consume(&stderr_buffer, len);
1635 	}
1636 
1637 	/* Clear and free any buffers. */
1638 	memset(buf, 0, sizeof(buf));
1639 	buffer_free(&stdin_buffer);
1640 	buffer_free(&stdout_buffer);
1641 	buffer_free(&stderr_buffer);
1642 
1643 	/* Report bytes transferred, and transfer rates. */
1644 	total_time = get_current_time() - start_time;
1645 	packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1646 	packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1647 	verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1648 	    (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1649 	if (total_time > 0)
1650 		verbose("Bytes per second: sent %.1f, received %.1f",
1651 		    obytes / total_time, ibytes / total_time);
1652 	/* Return the exit status of the program. */
1653 	debug("Exit status %d", exit_status);
1654 	return exit_status;
1655 }
1656 
1657 /*********/
1658 
1659 static void
1660 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1661 {
1662 	u_int data_len;
1663 	char *data = packet_get_string(&data_len);
1664 	packet_check_eom();
1665 	buffer_append(&stdout_buffer, data, data_len);
1666 	memset(data, 0, data_len);
1667 	xfree(data);
1668 }
1669 static void
1670 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1671 {
1672 	u_int data_len;
1673 	char *data = packet_get_string(&data_len);
1674 	packet_check_eom();
1675 	buffer_append(&stderr_buffer, data, data_len);
1676 	memset(data, 0, data_len);
1677 	xfree(data);
1678 }
1679 static void
1680 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1681 {
1682 	exit_status = packet_get_int();
1683 	packet_check_eom();
1684 	/* Acknowledge the exit. */
1685 	packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1686 	packet_send();
1687 	/*
1688 	 * Must wait for packet to be sent since we are
1689 	 * exiting the loop.
1690 	 */
1691 	packet_write_wait();
1692 	/* Flag that we want to exit. */
1693 	quit_pending = 1;
1694 }
1695 static void
1696 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1697 {
1698 	Channel *c = NULL;
1699 	int remote_id, sock;
1700 
1701 	/* Read the remote channel number from the message. */
1702 	remote_id = packet_get_int();
1703 	packet_check_eom();
1704 
1705 	/*
1706 	 * Get a connection to the local authentication agent (this may again
1707 	 * get forwarded).
1708 	 */
1709 	sock = ssh_get_authentication_socket();
1710 
1711 	/*
1712 	 * If we could not connect the agent, send an error message back to
1713 	 * the server. This should never happen unless the agent dies,
1714 	 * because authentication forwarding is only enabled if we have an
1715 	 * agent.
1716 	 */
1717 	if (sock >= 0) {
1718 		c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1719 		    -1, 0, 0, 0, "authentication agent connection", 1);
1720 		c->remote_id = remote_id;
1721 		c->force_drain = 1;
1722 	}
1723 	if (c == NULL) {
1724 		packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1725 		packet_put_int(remote_id);
1726 	} else {
1727 		/* Send a confirmation to the remote host. */
1728 		debug("Forwarding authentication connection.");
1729 		packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1730 		packet_put_int(remote_id);
1731 		packet_put_int(c->self);
1732 	}
1733 	packet_send();
1734 }
1735 
1736 static Channel *
1737 client_request_forwarded_tcpip(const char *request_type, int rchan)
1738 {
1739 	Channel *c = NULL;
1740 	char *listen_address, *originator_address;
1741 	u_short listen_port, originator_port;
1742 
1743 	/* Get rest of the packet */
1744 	listen_address = packet_get_string(NULL);
1745 	listen_port = packet_get_int();
1746 	originator_address = packet_get_string(NULL);
1747 	originator_port = packet_get_int();
1748 	packet_check_eom();
1749 
1750 	debug("client_request_forwarded_tcpip: listen %s port %d, "
1751 	    "originator %s port %d", listen_address, listen_port,
1752 	    originator_address, originator_port);
1753 
1754 	c = channel_connect_by_listen_address(listen_port,
1755 	    "forwarded-tcpip", originator_address);
1756 
1757 	xfree(originator_address);
1758 	xfree(listen_address);
1759 	return c;
1760 }
1761 
1762 static Channel *
1763 client_request_x11(const char *request_type, int rchan)
1764 {
1765 	Channel *c = NULL;
1766 	char *originator;
1767 	u_short originator_port;
1768 	int sock;
1769 
1770 	if (!options.forward_x11) {
1771 		error("Warning: ssh server tried X11 forwarding.");
1772 		error("Warning: this is probably a break-in attempt by a "
1773 		    "malicious server.");
1774 		return NULL;
1775 	}
1776 	if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1777 		verbose("Rejected X11 connection after ForwardX11Timeout "
1778 		    "expired");
1779 		return NULL;
1780 	}
1781 	originator = packet_get_string(NULL);
1782 	if (datafellows & SSH_BUG_X11FWD) {
1783 		debug2("buggy server: x11 request w/o originator_port");
1784 		originator_port = 0;
1785 	} else {
1786 		originator_port = packet_get_int();
1787 	}
1788 	packet_check_eom();
1789 	/* XXX check permission */
1790 	debug("client_request_x11: request from %s %d", originator,
1791 	    originator_port);
1792 	xfree(originator);
1793 	sock = x11_connect_display();
1794 	if (sock < 0)
1795 		return NULL;
1796 	/* again is this really necessary for X11? */
1797 	if (options.hpn_disabled)
1798 	c = channel_new("x11",
1799 	    SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1800 	    CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1801 	else
1802 		c = channel_new("x11",
1803 		    SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1804 		    options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1805 	c->force_drain = 1;
1806 	return c;
1807 }
1808 
1809 static Channel *
1810 client_request_agent(const char *request_type, int rchan)
1811 {
1812 	Channel *c = NULL;
1813 	int sock;
1814 
1815 	if (!options.forward_agent) {
1816 		error("Warning: ssh server tried agent forwarding.");
1817 		error("Warning: this is probably a break-in attempt by a "
1818 		    "malicious server.");
1819 		return NULL;
1820 	}
1821 	sock = ssh_get_authentication_socket();
1822 	if (sock < 0)
1823 		return NULL;
1824 	if (options.hpn_disabled)
1825 	c = channel_new("authentication agent connection",
1826 	    SSH_CHANNEL_OPEN, sock, sock, -1,
1827 		    CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1828 		    "authentication agent connection", 1);
1829        else
1830 	c = channel_new("authentication agent connection",
1831 	    SSH_CHANNEL_OPEN, sock, sock, -1,
1832                    options.hpn_buffer_size, options.hpn_buffer_size, 0,
1833 	    "authentication agent connection", 1);
1834 	c->force_drain = 1;
1835 	return c;
1836 }
1837 
1838 int
1839 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1840 {
1841 	Channel *c;
1842 	int fd;
1843 
1844 	if (tun_mode == SSH_TUNMODE_NO)
1845 		return 0;
1846 
1847 	if (!compat20) {
1848 		error("Tunnel forwarding is not supported for protocol 1");
1849 		return -1;
1850 	}
1851 
1852 	debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1853 
1854 	/* Open local tunnel device */
1855 	if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1856 		error("Tunnel device open failed.");
1857 		return -1;
1858 	}
1859 
1860 	if(options.hpn_disabled)
1861 	c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1862 				CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1863 				0, "tun", 1);
1864 	else
1865 	c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1866 				options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
1867 				0, "tun", 1);
1868 	c->datagram = 1;
1869 
1870 
1871 
1872 #if defined(SSH_TUN_FILTER)
1873 	if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1874 		channel_register_filter(c->self, sys_tun_infilter,
1875 		    sys_tun_outfilter, NULL, NULL);
1876 #endif
1877 
1878 	packet_start(SSH2_MSG_CHANNEL_OPEN);
1879 	packet_put_cstring("tun@openssh.com");
1880 	packet_put_int(c->self);
1881 	packet_put_int(c->local_window_max);
1882 	packet_put_int(c->local_maxpacket);
1883 	packet_put_int(tun_mode);
1884 	packet_put_int(remote_tun);
1885 	packet_send();
1886 
1887 	return 0;
1888 }
1889 
1890 /* XXXX move to generic input handler */
1891 static void
1892 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1893 {
1894 	Channel *c = NULL;
1895 	char *ctype;
1896 	int rchan;
1897 	u_int rmaxpack, rwindow, len;
1898 
1899 	ctype = packet_get_string(&len);
1900 	rchan = packet_get_int();
1901 	rwindow = packet_get_int();
1902 	rmaxpack = packet_get_int();
1903 
1904 	debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1905 	    ctype, rchan, rwindow, rmaxpack);
1906 
1907 	if (strcmp(ctype, "forwarded-tcpip") == 0) {
1908 		c = client_request_forwarded_tcpip(ctype, rchan);
1909 	} else if (strcmp(ctype, "x11") == 0) {
1910 		c = client_request_x11(ctype, rchan);
1911 	} else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1912 		c = client_request_agent(ctype, rchan);
1913 	}
1914 /* XXX duplicate : */
1915 	if (c != NULL) {
1916 		debug("confirm %s", ctype);
1917 		c->remote_id = rchan;
1918 		c->remote_window = rwindow;
1919 		c->remote_maxpacket = rmaxpack;
1920 		if (c->type != SSH_CHANNEL_CONNECTING) {
1921 			packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1922 			packet_put_int(c->remote_id);
1923 			packet_put_int(c->self);
1924 			packet_put_int(c->local_window);
1925 			packet_put_int(c->local_maxpacket);
1926 			packet_send();
1927 		}
1928 	} else {
1929 		debug("failure %s", ctype);
1930 		packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1931 		packet_put_int(rchan);
1932 		packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1933 		if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1934 			packet_put_cstring("open failed");
1935 			packet_put_cstring("");
1936 		}
1937 		packet_send();
1938 	}
1939 	xfree(ctype);
1940 }
1941 static void
1942 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1943 {
1944 	Channel *c = NULL;
1945 	int exitval, id, reply, success = 0;
1946 	char *rtype;
1947 
1948 	id = packet_get_int();
1949 	rtype = packet_get_string(NULL);
1950 	reply = packet_get_char();
1951 
1952 	debug("client_input_channel_req: channel %d rtype %s reply %d",
1953 	    id, rtype, reply);
1954 
1955 	if (id == -1) {
1956 		error("client_input_channel_req: request for channel -1");
1957 	} else if ((c = channel_lookup(id)) == NULL) {
1958 		error("client_input_channel_req: channel %d: "
1959 		    "unknown channel", id);
1960 	} else if (strcmp(rtype, "eow@openssh.com") == 0) {
1961 		packet_check_eom();
1962 		chan_rcvd_eow(c);
1963 	} else if (strcmp(rtype, "exit-status") == 0) {
1964 		exitval = packet_get_int();
1965 		if (c->ctl_chan != -1) {
1966 			mux_exit_message(c, exitval);
1967 			success = 1;
1968 		} else if (id == session_ident) {
1969 			/* Record exit value of local session */
1970 			success = 1;
1971 			exit_status = exitval;
1972 		} else {
1973 			/* Probably for a mux channel that has already closed */
1974 			debug("%s: no sink for exit-status on channel %d",
1975 			    __func__, id);
1976 		}
1977 		packet_check_eom();
1978 	}
1979 	if (reply && c != NULL) {
1980 		packet_start(success ?
1981 		    SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1982 		packet_put_int(c->remote_id);
1983 		packet_send();
1984 	}
1985 	xfree(rtype);
1986 }
1987 static void
1988 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1989 {
1990 	char *rtype;
1991 	int want_reply;
1992 	int success = 0;
1993 
1994 	rtype = packet_get_string(NULL);
1995 	want_reply = packet_get_char();
1996 	debug("client_input_global_request: rtype %s want_reply %d",
1997 	    rtype, want_reply);
1998 	if (want_reply) {
1999 		packet_start(success ?
2000 		    SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2001 		packet_send();
2002 		packet_write_wait();
2003 	}
2004 	xfree(rtype);
2005 }
2006 
2007 void
2008 client_session2_setup(int id, int want_tty, int want_subsystem,
2009     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2010 {
2011 	int len;
2012 	Channel *c = NULL;
2013 
2014 	debug2("%s: id %d", __func__, id);
2015 
2016 	if ((c = channel_lookup(id)) == NULL)
2017 		fatal("client_session2_setup: channel %d: unknown channel", id);
2018 
2019 	packet_set_interactive(want_tty,
2020 	    options.ip_qos_interactive, options.ip_qos_bulk);
2021 
2022 	if (want_tty) {
2023 		struct winsize ws;
2024 
2025 		/* Store window size in the packet. */
2026 		if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2027 			memset(&ws, 0, sizeof(ws));
2028 
2029 		channel_request_start(id, "pty-req", 1);
2030 		client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2031 		packet_put_cstring(term != NULL ? term : "");
2032 		packet_put_int((u_int)ws.ws_col);
2033 		packet_put_int((u_int)ws.ws_row);
2034 		packet_put_int((u_int)ws.ws_xpixel);
2035 		packet_put_int((u_int)ws.ws_ypixel);
2036 		if (tiop == NULL)
2037 			tiop = get_saved_tio();
2038 		tty_make_modes(-1, tiop);
2039 		packet_send();
2040 		/* XXX wait for reply */
2041 		c->client_tty = 1;
2042 	}
2043 
2044 	/* Transfer any environment variables from client to server */
2045 	if (options.num_send_env != 0 && env != NULL) {
2046 		int i, j, matched;
2047 		char *name, *val;
2048 
2049 		debug("Sending environment.");
2050 		for (i = 0; env[i] != NULL; i++) {
2051 			/* Split */
2052 			name = xstrdup(env[i]);
2053 			if ((val = strchr(name, '=')) == NULL) {
2054 				xfree(name);
2055 				continue;
2056 			}
2057 			*val++ = '\0';
2058 
2059 			matched = 0;
2060 			for (j = 0; j < options.num_send_env; j++) {
2061 				if (match_pattern(name, options.send_env[j])) {
2062 					matched = 1;
2063 					break;
2064 				}
2065 			}
2066 			if (!matched) {
2067 				debug3("Ignored env %s", name);
2068 				xfree(name);
2069 				continue;
2070 			}
2071 
2072 			debug("Sending env %s = %s", name, val);
2073 			channel_request_start(id, "env", 0);
2074 			packet_put_cstring(name);
2075 			packet_put_cstring(val);
2076 			packet_send();
2077 			xfree(name);
2078 		}
2079 	}
2080 
2081 	len = buffer_len(cmd);
2082 	if (len > 0) {
2083 		if (len > 900)
2084 			len = 900;
2085 		if (want_subsystem) {
2086 			debug("Sending subsystem: %.*s",
2087 			    len, (u_char*)buffer_ptr(cmd));
2088 			channel_request_start(id, "subsystem", 1);
2089 			client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2090 		} else {
2091 			debug("Sending command: %.*s",
2092 			    len, (u_char*)buffer_ptr(cmd));
2093 			channel_request_start(id, "exec", 1);
2094 			client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2095 		}
2096 		packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2097 		packet_send();
2098 	} else {
2099 		channel_request_start(id, "shell", 1);
2100 		client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2101 		packet_send();
2102 	}
2103 }
2104 
2105 static void
2106 client_init_dispatch_20(void)
2107 {
2108 	dispatch_init(&dispatch_protocol_error);
2109 
2110 	dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2111 	dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2112 	dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2113 	dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2114 	dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2115 	dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2116 	dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2117 	dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2118 	dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2119 	dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2120 	dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2121 	dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2122 
2123 	/* rekeying */
2124 	dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2125 
2126 	/* global request reply messages */
2127 	dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2128 	dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2129 }
2130 
2131 static void
2132 client_init_dispatch_13(void)
2133 {
2134 	dispatch_init(NULL);
2135 	dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2136 	dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2137 	dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2138 	dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2139 	dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2140 	dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2141 	dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2142 	dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2143 	dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2144 
2145 	dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2146 	    &client_input_agent_open : &deny_input_open);
2147 	dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2148 	    &x11_input_open : &deny_input_open);
2149 }
2150 
2151 static void
2152 client_init_dispatch_15(void)
2153 {
2154 	client_init_dispatch_13();
2155 	dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2156 	dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2157 }
2158 
2159 static void
2160 client_init_dispatch(void)
2161 {
2162 	if (compat20)
2163 		client_init_dispatch_20();
2164 	else if (compat13)
2165 		client_init_dispatch_13();
2166 	else
2167 		client_init_dispatch_15();
2168 }
2169 
2170 void
2171 client_stop_mux(void)
2172 {
2173 	if (options.control_path != NULL && muxserver_sock != -1)
2174 		unlink(options.control_path);
2175 	/*
2176 	 * If we are in persist mode, signal that we should close when all
2177 	 * active channels are closed.
2178 	 */
2179 	if (options.control_persist) {
2180 		session_closed = 1;
2181 		setproctitle("[stopped mux]");
2182 	}
2183 }
2184 
2185 /* client specific fatal cleanup */
2186 void
2187 cleanup_exit(int i)
2188 {
2189 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2190 	leave_non_blocking();
2191 	if (options.control_path != NULL && muxserver_sock != -1)
2192 		unlink(options.control_path);
2193 	ssh_kill_proxy_command();
2194 	_exit(i);
2195 }
2196