xref: /openbsd-src/usr.bin/ssh/clientloop.c (revision 8500990981f885cbe5e6a4958549cacc238b5ae6)
1 /*
2  * Author: Tatu Ylonen <ylo@cs.hut.fi>
3  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4  *                    All rights reserved
5  * The main loop for the interactive session (client side).
6  *
7  * As far as I am concerned, the code I have written for this software
8  * can be used freely for any purpose.  Any derived versions of this
9  * software must be clearly marked as such, and if the derived work is
10  * incompatible with the protocol description in the RFC file, it must be
11  * called by a name other than "ssh" or "Secure Shell".
12  *
13  *
14  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
15  *
16  * Redistribution and use in source and binary forms, with or without
17  * modification, are permitted provided that the following conditions
18  * are met:
19  * 1. Redistributions of source code must retain the above copyright
20  *    notice, this list of conditions and the following disclaimer.
21  * 2. Redistributions in binary form must reproduce the above copyright
22  *    notice, this list of conditions and the following disclaimer in the
23  *    documentation and/or other materials provided with the distribution.
24  *
25  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35  *
36  *
37  * SSH2 support added by Markus Friedl.
38  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
39  *
40  * Redistribution and use in source and binary forms, with or without
41  * modification, are permitted provided that the following conditions
42  * are met:
43  * 1. Redistributions of source code must retain the above copyright
44  *    notice, this list of conditions and the following disclaimer.
45  * 2. Redistributions in binary form must reproduce the above copyright
46  *    notice, this list of conditions and the following disclaimer in the
47  *    documentation and/or other materials provided with the distribution.
48  *
49  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
50  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
51  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
52  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
53  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
54  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
55  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
56  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
57  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
58  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
59  */
60 
61 #include "includes.h"
62 RCSID("$OpenBSD: clientloop.c,v 1.115 2003/09/23 20:41:11 markus Exp $");
63 
64 #include "ssh.h"
65 #include "ssh1.h"
66 #include "ssh2.h"
67 #include "xmalloc.h"
68 #include "packet.h"
69 #include "buffer.h"
70 #include "compat.h"
71 #include "channels.h"
72 #include "dispatch.h"
73 #include "buffer.h"
74 #include "bufaux.h"
75 #include "key.h"
76 #include "kex.h"
77 #include "log.h"
78 #include "readconf.h"
79 #include "clientloop.h"
80 #include "authfd.h"
81 #include "atomicio.h"
82 #include "sshtty.h"
83 #include "misc.h"
84 #include "readpass.h"
85 
86 /* import options */
87 extern Options options;
88 
89 /* Flag indicating that stdin should be redirected from /dev/null. */
90 extern int stdin_null_flag;
91 
92 /*
93  * Name of the host we are connecting to.  This is the name given on the
94  * command line, or the HostName specified for the user-supplied name in a
95  * configuration file.
96  */
97 extern char *host;
98 
99 /*
100  * Flag to indicate that we have received a window change signal which has
101  * not yet been processed.  This will cause a message indicating the new
102  * window size to be sent to the server a little later.  This is volatile
103  * because this is updated in a signal handler.
104  */
105 static volatile sig_atomic_t received_window_change_signal = 0;
106 static volatile sig_atomic_t received_signal = 0;
107 
108 /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
109 static int in_non_blocking_mode = 0;
110 
111 /* Common data for the client loop code. */
112 static int quit_pending;	/* Set to non-zero to quit the client loop. */
113 static int escape_char;		/* Escape character. */
114 static int escape_pending;	/* Last character was the escape character */
115 static int last_was_cr;		/* Last character was a newline. */
116 static int exit_status;		/* Used to store the exit status of the command. */
117 static int stdin_eof;		/* EOF has been encountered on standard error. */
118 static Buffer stdin_buffer;	/* Buffer for stdin data. */
119 static Buffer stdout_buffer;	/* Buffer for stdout data. */
120 static Buffer stderr_buffer;	/* Buffer for stderr data. */
121 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
122 static u_int buffer_high;/* Soft max buffer size. */
123 static int connection_in;	/* Connection to server (input). */
124 static int connection_out;	/* Connection to server (output). */
125 static int need_rekeying;	/* Set to non-zero if rekeying is requested. */
126 static int session_closed = 0;	/* In SSH2: login session closed. */
127 
128 static void client_init_dispatch(void);
129 int	session_ident = -1;
130 
131 /*XXX*/
132 extern Kex *xxx_kex;
133 
134 /* Restores stdin to blocking mode. */
135 
136 static void
137 leave_non_blocking(void)
138 {
139 	if (in_non_blocking_mode) {
140 		(void) fcntl(fileno(stdin), F_SETFL, 0);
141 		in_non_blocking_mode = 0;
142 	}
143 }
144 
145 /* Puts stdin terminal in non-blocking mode. */
146 
147 static void
148 enter_non_blocking(void)
149 {
150 	in_non_blocking_mode = 1;
151 	(void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
152 }
153 
154 /*
155  * Signal handler for the window change signal (SIGWINCH).  This just sets a
156  * flag indicating that the window has changed.
157  */
158 
159 static void
160 window_change_handler(int sig)
161 {
162 	received_window_change_signal = 1;
163 	signal(SIGWINCH, window_change_handler);
164 }
165 
166 /*
167  * Signal handler for signals that cause the program to terminate.  These
168  * signals must be trapped to restore terminal modes.
169  */
170 
171 static void
172 signal_handler(int sig)
173 {
174 	received_signal = sig;
175 	quit_pending = 1;
176 }
177 
178 /*
179  * Returns current time in seconds from Jan 1, 1970 with the maximum
180  * available resolution.
181  */
182 
183 static double
184 get_current_time(void)
185 {
186 	struct timeval tv;
187 	gettimeofday(&tv, NULL);
188 	return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
189 }
190 
191 /*
192  * This is called when the interactive is entered.  This checks if there is
193  * an EOF coming on stdin.  We must check this explicitly, as select() does
194  * not appear to wake up when redirecting from /dev/null.
195  */
196 
197 static void
198 client_check_initial_eof_on_stdin(void)
199 {
200 	int len;
201 	char buf[1];
202 
203 	/*
204 	 * If standard input is to be "redirected from /dev/null", we simply
205 	 * mark that we have seen an EOF and send an EOF message to the
206 	 * server. Otherwise, we try to read a single character; it appears
207 	 * that for some files, such /dev/null, select() never wakes up for
208 	 * read for this descriptor, which means that we never get EOF.  This
209 	 * way we will get the EOF if stdin comes from /dev/null or similar.
210 	 */
211 	if (stdin_null_flag) {
212 		/* Fake EOF on stdin. */
213 		debug("Sending eof.");
214 		stdin_eof = 1;
215 		packet_start(SSH_CMSG_EOF);
216 		packet_send();
217 	} else {
218 		enter_non_blocking();
219 
220 		/* Check for immediate EOF on stdin. */
221 		len = read(fileno(stdin), buf, 1);
222 		if (len == 0) {
223 			/* EOF.  Record that we have seen it and send EOF to server. */
224 			debug("Sending eof.");
225 			stdin_eof = 1;
226 			packet_start(SSH_CMSG_EOF);
227 			packet_send();
228 		} else if (len > 0) {
229 			/*
230 			 * Got data.  We must store the data in the buffer,
231 			 * and also process it as an escape character if
232 			 * appropriate.
233 			 */
234 			if ((u_char) buf[0] == escape_char)
235 				escape_pending = 1;
236 			else
237 				buffer_append(&stdin_buffer, buf, 1);
238 		}
239 		leave_non_blocking();
240 	}
241 }
242 
243 
244 /*
245  * Make packets from buffered stdin data, and buffer them for sending to the
246  * connection.
247  */
248 
249 static void
250 client_make_packets_from_stdin_data(void)
251 {
252 	u_int len;
253 
254 	/* Send buffered stdin data to the server. */
255 	while (buffer_len(&stdin_buffer) > 0 &&
256 	    packet_not_very_much_data_to_write()) {
257 		len = buffer_len(&stdin_buffer);
258 		/* Keep the packets at reasonable size. */
259 		if (len > packet_get_maxsize())
260 			len = packet_get_maxsize();
261 		packet_start(SSH_CMSG_STDIN_DATA);
262 		packet_put_string(buffer_ptr(&stdin_buffer), len);
263 		packet_send();
264 		buffer_consume(&stdin_buffer, len);
265 		stdin_bytes += len;
266 		/* If we have a pending EOF, send it now. */
267 		if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
268 			packet_start(SSH_CMSG_EOF);
269 			packet_send();
270 		}
271 	}
272 }
273 
274 /*
275  * Checks if the client window has changed, and sends a packet about it to
276  * the server if so.  The actual change is detected elsewhere (by a software
277  * interrupt on Unix); this just checks the flag and sends a message if
278  * appropriate.
279  */
280 
281 static void
282 client_check_window_change(void)
283 {
284 	struct winsize ws;
285 
286 	if (! received_window_change_signal)
287 		return;
288 	/** XXX race */
289 	received_window_change_signal = 0;
290 
291 	if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
292 		return;
293 
294 	debug2("client_check_window_change: changed");
295 
296 	if (compat20) {
297 		channel_request_start(session_ident, "window-change", 0);
298 		packet_put_int(ws.ws_col);
299 		packet_put_int(ws.ws_row);
300 		packet_put_int(ws.ws_xpixel);
301 		packet_put_int(ws.ws_ypixel);
302 		packet_send();
303 	} else {
304 		packet_start(SSH_CMSG_WINDOW_SIZE);
305 		packet_put_int(ws.ws_row);
306 		packet_put_int(ws.ws_col);
307 		packet_put_int(ws.ws_xpixel);
308 		packet_put_int(ws.ws_ypixel);
309 		packet_send();
310 	}
311 }
312 
313 /*
314  * Waits until the client can do something (some data becomes available on
315  * one of the file descriptors).
316  */
317 
318 static void
319 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
320     int *maxfdp, int *nallocp, int rekeying)
321 {
322 	/* Add any selections by the channel mechanism. */
323 	channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
324 
325 	if (!compat20) {
326 		/* Read from the connection, unless our buffers are full. */
327 		if (buffer_len(&stdout_buffer) < buffer_high &&
328 		    buffer_len(&stderr_buffer) < buffer_high &&
329 		    channel_not_very_much_buffered_data())
330 			FD_SET(connection_in, *readsetp);
331 		/*
332 		 * Read from stdin, unless we have seen EOF or have very much
333 		 * buffered data to send to the server.
334 		 */
335 		if (!stdin_eof && packet_not_very_much_data_to_write())
336 			FD_SET(fileno(stdin), *readsetp);
337 
338 		/* Select stdout/stderr if have data in buffer. */
339 		if (buffer_len(&stdout_buffer) > 0)
340 			FD_SET(fileno(stdout), *writesetp);
341 		if (buffer_len(&stderr_buffer) > 0)
342 			FD_SET(fileno(stderr), *writesetp);
343 	} else {
344 		/* channel_prepare_select could have closed the last channel */
345 		if (session_closed && !channel_still_open() &&
346 		    !packet_have_data_to_write()) {
347 			/* clear mask since we did not call select() */
348 			memset(*readsetp, 0, *nallocp);
349 			memset(*writesetp, 0, *nallocp);
350 			return;
351 		} else {
352 			FD_SET(connection_in, *readsetp);
353 		}
354 	}
355 
356 	/* Select server connection if have data to write to the server. */
357 	if (packet_have_data_to_write())
358 		FD_SET(connection_out, *writesetp);
359 
360 	/*
361 	 * Wait for something to happen.  This will suspend the process until
362 	 * some selected descriptor can be read, written, or has some other
363 	 * event pending. Note: if you want to implement SSH_MSG_IGNORE
364 	 * messages to fool traffic analysis, this might be the place to do
365 	 * it: just have a random timeout for the select, and send a random
366 	 * SSH_MSG_IGNORE packet when the timeout expires.
367 	 */
368 
369 	if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
370 		char buf[100];
371 
372 		/*
373 		 * We have to clear the select masks, because we return.
374 		 * We have to return, because the mainloop checks for the flags
375 		 * set by the signal handlers.
376 		 */
377 		memset(*readsetp, 0, *nallocp);
378 		memset(*writesetp, 0, *nallocp);
379 
380 		if (errno == EINTR)
381 			return;
382 		/* Note: we might still have data in the buffers. */
383 		snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
384 		buffer_append(&stderr_buffer, buf, strlen(buf));
385 		quit_pending = 1;
386 	}
387 }
388 
389 static void
390 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
391 {
392 	struct winsize oldws, newws;
393 
394 	/* Flush stdout and stderr buffers. */
395 	if (buffer_len(bout) > 0)
396 		atomicio(vwrite, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
397 	if (buffer_len(berr) > 0)
398 		atomicio(vwrite, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
399 
400 	leave_raw_mode();
401 
402 	/*
403 	 * Free (and clear) the buffer to reduce the amount of data that gets
404 	 * written to swap.
405 	 */
406 	buffer_free(bin);
407 	buffer_free(bout);
408 	buffer_free(berr);
409 
410 	/* Save old window size. */
411 	ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
412 
413 	/* Send the suspend signal to the program itself. */
414 	kill(getpid(), SIGTSTP);
415 
416 	/* Check if the window size has changed. */
417 	if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
418 	    (oldws.ws_row != newws.ws_row ||
419 	    oldws.ws_col != newws.ws_col ||
420 	    oldws.ws_xpixel != newws.ws_xpixel ||
421 	    oldws.ws_ypixel != newws.ws_ypixel))
422 		received_window_change_signal = 1;
423 
424 	/* OK, we have been continued by the user. Reinitialize buffers. */
425 	buffer_init(bin);
426 	buffer_init(bout);
427 	buffer_init(berr);
428 
429 	enter_raw_mode();
430 }
431 
432 static void
433 client_process_net_input(fd_set * readset)
434 {
435 	int len;
436 	char buf[8192];
437 
438 	/*
439 	 * Read input from the server, and add any such data to the buffer of
440 	 * the packet subsystem.
441 	 */
442 	if (FD_ISSET(connection_in, readset)) {
443 		/* Read as much as possible. */
444 		len = read(connection_in, buf, sizeof(buf));
445 		if (len == 0) {
446 			/* Received EOF.  The remote host has closed the connection. */
447 			snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
448 				 host);
449 			buffer_append(&stderr_buffer, buf, strlen(buf));
450 			quit_pending = 1;
451 			return;
452 		}
453 		/*
454 		 * There is a kernel bug on Solaris that causes select to
455 		 * sometimes wake up even though there is no data available.
456 		 */
457 		if (len < 0 && (errno == EAGAIN || errno == EINTR))
458 			len = 0;
459 
460 		if (len < 0) {
461 			/* An error has encountered.  Perhaps there is a network problem. */
462 			snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
463 				 host, strerror(errno));
464 			buffer_append(&stderr_buffer, buf, strlen(buf));
465 			quit_pending = 1;
466 			return;
467 		}
468 		packet_process_incoming(buf, len);
469 	}
470 }
471 
472 static void
473 process_cmdline(void)
474 {
475 	void (*handler)(int);
476 	char *s, *cmd;
477 	u_short fwd_port, fwd_host_port;
478 	char buf[1024], sfwd_port[6], sfwd_host_port[6];
479 	int local = 0;
480 
481 	leave_raw_mode();
482 	handler = signal(SIGINT, SIG_IGN);
483 	cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
484 	if (s == NULL)
485 		goto out;
486 	while (*s && isspace(*s))
487 		s++;
488 	if (*s == 0)
489 		goto out;
490 	if (strlen(s) < 2 || s[0] != '-' || !(s[1] == 'L' || s[1] == 'R')) {
491 		logit("Invalid command.");
492 		goto out;
493 	}
494 	if (s[1] == 'L')
495 		local = 1;
496 	if (!local && !compat20) {
497 		logit("Not supported for SSH protocol version 1.");
498 		goto out;
499 	}
500 	s += 2;
501 	while (*s && isspace(*s))
502 		s++;
503 
504 	if (sscanf(s, "%5[0-9]:%255[^:]:%5[0-9]",
505 	    sfwd_port, buf, sfwd_host_port) != 3 &&
506 	    sscanf(s, "%5[0-9]/%255[^/]/%5[0-9]",
507 	    sfwd_port, buf, sfwd_host_port) != 3) {
508 		logit("Bad forwarding specification.");
509 		goto out;
510 	}
511 	if ((fwd_port = a2port(sfwd_port)) == 0 ||
512 	    (fwd_host_port = a2port(sfwd_host_port)) == 0) {
513 		logit("Bad forwarding port(s).");
514 		goto out;
515 	}
516 	if (local) {
517 		if (channel_setup_local_fwd_listener(fwd_port, buf,
518 		    fwd_host_port, options.gateway_ports) < 0) {
519 			logit("Port forwarding failed.");
520 			goto out;
521 		}
522 	} else
523 		channel_request_remote_forwarding(fwd_port, buf,
524 		    fwd_host_port);
525 	logit("Forwarding port.");
526 out:
527 	signal(SIGINT, handler);
528 	enter_raw_mode();
529 	if (cmd)
530 		xfree(cmd);
531 }
532 
533 /* process the characters one by one */
534 static int
535 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
536 {
537 	char string[1024];
538 	pid_t pid;
539 	int bytes = 0;
540 	u_int i;
541 	u_char ch;
542 	char *s;
543 
544 	for (i = 0; i < len; i++) {
545 		/* Get one character at a time. */
546 		ch = buf[i];
547 
548 		if (escape_pending) {
549 			/* We have previously seen an escape character. */
550 			/* Clear the flag now. */
551 			escape_pending = 0;
552 
553 			/* Process the escaped character. */
554 			switch (ch) {
555 			case '.':
556 				/* Terminate the connection. */
557 				snprintf(string, sizeof string, "%c.\r\n", escape_char);
558 				buffer_append(berr, string, strlen(string));
559 
560 				quit_pending = 1;
561 				return -1;
562 
563 			case 'Z' - 64:
564 				/* Suspend the program. */
565 				/* Print a message to that effect to the user. */
566 				snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
567 				buffer_append(berr, string, strlen(string));
568 
569 				/* Restore terminal modes and suspend. */
570 				client_suspend_self(bin, bout, berr);
571 
572 				/* We have been continued. */
573 				continue;
574 
575 			case 'B':
576 				if (compat20) {
577 					snprintf(string, sizeof string,
578 					    "%cB\r\n", escape_char);
579 					buffer_append(berr, string,
580 					    strlen(string));
581 					channel_request_start(session_ident,
582 					    "break", 0);
583 					packet_put_int(1000);
584 					packet_send();
585 				}
586 				continue;
587 
588 			case 'R':
589 				if (compat20) {
590 					if (datafellows & SSH_BUG_NOREKEY)
591 						logit("Server does not support re-keying");
592 					else
593 						need_rekeying = 1;
594 				}
595 				continue;
596 
597 			case '&':
598 				/*
599 				 * Detach the program (continue to serve connections,
600 				 * but put in background and no more new connections).
601 				 */
602 				/* Restore tty modes. */
603 				leave_raw_mode();
604 
605 				/* Stop listening for new connections. */
606 				channel_stop_listening();
607 
608 				snprintf(string, sizeof string,
609 				    "%c& [backgrounded]\n", escape_char);
610 				buffer_append(berr, string, strlen(string));
611 
612 				/* Fork into background. */
613 				pid = fork();
614 				if (pid < 0) {
615 					error("fork: %.100s", strerror(errno));
616 					continue;
617 				}
618 				if (pid != 0) {	/* This is the parent. */
619 					/* The parent just exits. */
620 					exit(0);
621 				}
622 				/* The child continues serving connections. */
623 				if (compat20) {
624 					buffer_append(bin, "\004", 1);
625 					/* fake EOF on stdin */
626 					return -1;
627 				} else if (!stdin_eof) {
628 					/*
629 					 * Sending SSH_CMSG_EOF alone does not always appear
630 					 * to be enough.  So we try to send an EOF character
631 					 * first.
632 					 */
633 					packet_start(SSH_CMSG_STDIN_DATA);
634 					packet_put_string("\004", 1);
635 					packet_send();
636 					/* Close stdin. */
637 					stdin_eof = 1;
638 					if (buffer_len(bin) == 0) {
639 						packet_start(SSH_CMSG_EOF);
640 						packet_send();
641 					}
642 				}
643 				continue;
644 
645 			case '?':
646 				snprintf(string, sizeof string,
647 "%c?\r\n\
648 Supported escape sequences:\r\n\
649 %c.  - terminate connection\r\n\
650 %cB  - send a BREAK to the remote system\r\n\
651 %cC  - open a command line\r\n\
652 %cR  - Request rekey (SSH protocol 2 only)\r\n\
653 %c^Z - suspend ssh\r\n\
654 %c#  - list forwarded connections\r\n\
655 %c&  - background ssh (when waiting for connections to terminate)\r\n\
656 %c?  - this message\r\n\
657 %c%c  - send the escape character by typing it twice\r\n\
658 (Note that escapes are only recognized immediately after newline.)\r\n",
659 				    escape_char, escape_char, escape_char, escape_char,
660 				    escape_char, escape_char, escape_char, escape_char,
661 				    escape_char, escape_char, escape_char);
662 				buffer_append(berr, string, strlen(string));
663 				continue;
664 
665 			case '#':
666 				snprintf(string, sizeof string, "%c#\r\n", escape_char);
667 				buffer_append(berr, string, strlen(string));
668 				s = channel_open_message();
669 				buffer_append(berr, s, strlen(s));
670 				xfree(s);
671 				continue;
672 
673 			case 'C':
674 				process_cmdline();
675 				continue;
676 
677 			default:
678 				if (ch != escape_char) {
679 					buffer_put_char(bin, escape_char);
680 					bytes++;
681 				}
682 				/* Escaped characters fall through here */
683 				break;
684 			}
685 		} else {
686 			/*
687 			 * The previous character was not an escape char. Check if this
688 			 * is an escape.
689 			 */
690 			if (last_was_cr && ch == escape_char) {
691 				/* It is. Set the flag and continue to next character. */
692 				escape_pending = 1;
693 				continue;
694 			}
695 		}
696 
697 		/*
698 		 * Normal character.  Record whether it was a newline,
699 		 * and append it to the buffer.
700 		 */
701 		last_was_cr = (ch == '\r' || ch == '\n');
702 		buffer_put_char(bin, ch);
703 		bytes++;
704 	}
705 	return bytes;
706 }
707 
708 static void
709 client_process_input(fd_set * readset)
710 {
711 	int len;
712 	char buf[8192];
713 
714 	/* Read input from stdin. */
715 	if (FD_ISSET(fileno(stdin), readset)) {
716 		/* Read as much as possible. */
717 		len = read(fileno(stdin), buf, sizeof(buf));
718 		if (len < 0 && (errno == EAGAIN || errno == EINTR))
719 			return;		/* we'll try again later */
720 		if (len <= 0) {
721 			/*
722 			 * Received EOF or error.  They are treated
723 			 * similarly, except that an error message is printed
724 			 * if it was an error condition.
725 			 */
726 			if (len < 0) {
727 				snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
728 				buffer_append(&stderr_buffer, buf, strlen(buf));
729 			}
730 			/* Mark that we have seen EOF. */
731 			stdin_eof = 1;
732 			/*
733 			 * Send an EOF message to the server unless there is
734 			 * data in the buffer.  If there is data in the
735 			 * buffer, no message will be sent now.  Code
736 			 * elsewhere will send the EOF when the buffer
737 			 * becomes empty if stdin_eof is set.
738 			 */
739 			if (buffer_len(&stdin_buffer) == 0) {
740 				packet_start(SSH_CMSG_EOF);
741 				packet_send();
742 			}
743 		} else if (escape_char == SSH_ESCAPECHAR_NONE) {
744 			/*
745 			 * Normal successful read, and no escape character.
746 			 * Just append the data to buffer.
747 			 */
748 			buffer_append(&stdin_buffer, buf, len);
749 		} else {
750 			/*
751 			 * Normal, successful read.  But we have an escape character
752 			 * and have to process the characters one by one.
753 			 */
754 			if (process_escapes(&stdin_buffer, &stdout_buffer,
755 			    &stderr_buffer, buf, len) == -1)
756 				return;
757 		}
758 	}
759 }
760 
761 static void
762 client_process_output(fd_set * writeset)
763 {
764 	int len;
765 	char buf[100];
766 
767 	/* Write buffered output to stdout. */
768 	if (FD_ISSET(fileno(stdout), writeset)) {
769 		/* Write as much data as possible. */
770 		len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
771 		    buffer_len(&stdout_buffer));
772 		if (len <= 0) {
773 			if (errno == EINTR || errno == EAGAIN)
774 				len = 0;
775 			else {
776 				/*
777 				 * An error or EOF was encountered.  Put an
778 				 * error message to stderr buffer.
779 				 */
780 				snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
781 				buffer_append(&stderr_buffer, buf, strlen(buf));
782 				quit_pending = 1;
783 				return;
784 			}
785 		}
786 		/* Consume printed data from the buffer. */
787 		buffer_consume(&stdout_buffer, len);
788 		stdout_bytes += len;
789 	}
790 	/* Write buffered output to stderr. */
791 	if (FD_ISSET(fileno(stderr), writeset)) {
792 		/* Write as much data as possible. */
793 		len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
794 		    buffer_len(&stderr_buffer));
795 		if (len <= 0) {
796 			if (errno == EINTR || errno == EAGAIN)
797 				len = 0;
798 			else {
799 				/* EOF or error, but can't even print error message. */
800 				quit_pending = 1;
801 				return;
802 			}
803 		}
804 		/* Consume printed characters from the buffer. */
805 		buffer_consume(&stderr_buffer, len);
806 		stderr_bytes += len;
807 	}
808 }
809 
810 /*
811  * Get packets from the connection input buffer, and process them as long as
812  * there are packets available.
813  *
814  * Any unknown packets received during the actual
815  * session cause the session to terminate.  This is
816  * intended to make debugging easier since no
817  * confirmations are sent.  Any compatible protocol
818  * extensions must be negotiated during the
819  * preparatory phase.
820  */
821 
822 static void
823 client_process_buffered_input_packets(void)
824 {
825 	dispatch_run(DISPATCH_NONBLOCK, &quit_pending, compat20 ? xxx_kex : NULL);
826 }
827 
828 /* scan buf[] for '~' before sending data to the peer */
829 
830 static int
831 simple_escape_filter(Channel *c, char *buf, int len)
832 {
833 	/* XXX we assume c->extended is writeable */
834 	return process_escapes(&c->input, &c->output, &c->extended, buf, len);
835 }
836 
837 static void
838 client_channel_closed(int id, void *arg)
839 {
840 	if (id != session_ident)
841 		error("client_channel_closed: id %d != session_ident %d",
842 		    id, session_ident);
843 	channel_cancel_cleanup(id);
844 	session_closed = 1;
845 	leave_raw_mode();
846 }
847 
848 /*
849  * Implements the interactive session with the server.  This is called after
850  * the user has been authenticated, and a command has been started on the
851  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
852  * used as an escape character for terminating or suspending the session.
853  */
854 
855 int
856 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
857 {
858 	fd_set *readset = NULL, *writeset = NULL;
859 	double start_time, total_time;
860 	int max_fd = 0, max_fd2 = 0, len, rekeying = 0, nalloc = 0;
861 	char buf[100];
862 
863 	debug("Entering interactive session.");
864 
865 	start_time = get_current_time();
866 
867 	/* Initialize variables. */
868 	escape_pending = 0;
869 	last_was_cr = 1;
870 	exit_status = -1;
871 	stdin_eof = 0;
872 	buffer_high = 64 * 1024;
873 	connection_in = packet_get_connection_in();
874 	connection_out = packet_get_connection_out();
875 	max_fd = MAX(connection_in, connection_out);
876 
877 	if (!compat20) {
878 		/* enable nonblocking unless tty */
879 		if (!isatty(fileno(stdin)))
880 			set_nonblock(fileno(stdin));
881 		if (!isatty(fileno(stdout)))
882 			set_nonblock(fileno(stdout));
883 		if (!isatty(fileno(stderr)))
884 			set_nonblock(fileno(stderr));
885 		max_fd = MAX(max_fd, fileno(stdin));
886 		max_fd = MAX(max_fd, fileno(stdout));
887 		max_fd = MAX(max_fd, fileno(stderr));
888 	}
889 	stdin_bytes = 0;
890 	stdout_bytes = 0;
891 	stderr_bytes = 0;
892 	quit_pending = 0;
893 	escape_char = escape_char_arg;
894 
895 	/* Initialize buffers. */
896 	buffer_init(&stdin_buffer);
897 	buffer_init(&stdout_buffer);
898 	buffer_init(&stderr_buffer);
899 
900 	client_init_dispatch();
901 
902 	/*
903 	 * Set signal handlers, (e.g. to restore non-blocking mode)
904 	 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
905 	 */
906 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
907 		signal(SIGINT, signal_handler);
908 	if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
909 		signal(SIGQUIT, signal_handler);
910 	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
911 		signal(SIGTERM, signal_handler);
912 	if (have_pty)
913 		signal(SIGWINCH, window_change_handler);
914 
915 	if (have_pty)
916 		enter_raw_mode();
917 
918 	if (compat20) {
919 		session_ident = ssh2_chan_id;
920 		if (escape_char != SSH_ESCAPECHAR_NONE)
921 			channel_register_filter(session_ident,
922 			    simple_escape_filter);
923 		if (session_ident != -1)
924 			channel_register_cleanup(session_ident,
925 			    client_channel_closed);
926 	} else {
927 		/* Check if we should immediately send eof on stdin. */
928 		client_check_initial_eof_on_stdin();
929 	}
930 
931 	/* Main loop of the client for the interactive session mode. */
932 	while (!quit_pending) {
933 
934 		/* Process buffered packets sent by the server. */
935 		client_process_buffered_input_packets();
936 
937 		if (compat20 && session_closed && !channel_still_open())
938 			break;
939 
940 		rekeying = (xxx_kex != NULL && !xxx_kex->done);
941 
942 		if (rekeying) {
943 			debug("rekeying in progress");
944 		} else {
945 			/*
946 			 * Make packets of buffered stdin data, and buffer
947 			 * them for sending to the server.
948 			 */
949 			if (!compat20)
950 				client_make_packets_from_stdin_data();
951 
952 			/*
953 			 * Make packets from buffered channel data, and
954 			 * enqueue them for sending to the server.
955 			 */
956 			if (packet_not_very_much_data_to_write())
957 				channel_output_poll();
958 
959 			/*
960 			 * Check if the window size has changed, and buffer a
961 			 * message about it to the server if so.
962 			 */
963 			client_check_window_change();
964 
965 			if (quit_pending)
966 				break;
967 		}
968 		/*
969 		 * Wait until we have something to do (something becomes
970 		 * available on one of the descriptors).
971 		 */
972 		max_fd2 = max_fd;
973 		client_wait_until_can_do_something(&readset, &writeset,
974 		    &max_fd2, &nalloc, rekeying);
975 
976 		if (quit_pending)
977 			break;
978 
979 		/* Do channel operations unless rekeying in progress. */
980 		if (!rekeying) {
981 			channel_after_select(readset, writeset);
982 			if (need_rekeying || packet_need_rekeying()) {
983 				debug("need rekeying");
984 				xxx_kex->done = 0;
985 				kex_send_kexinit(xxx_kex);
986 				need_rekeying = 0;
987 			}
988 		}
989 
990 		/* Buffer input from the connection.  */
991 		client_process_net_input(readset);
992 
993 		if (quit_pending)
994 			break;
995 
996 		if (!compat20) {
997 			/* Buffer data from stdin */
998 			client_process_input(readset);
999 			/*
1000 			 * Process output to stdout and stderr.  Output to
1001 			 * the connection is processed elsewhere (above).
1002 			 */
1003 			client_process_output(writeset);
1004 		}
1005 
1006 		/* Send as much buffered packet data as possible to the sender. */
1007 		if (FD_ISSET(connection_out, writeset))
1008 			packet_write_poll();
1009 	}
1010 	if (readset)
1011 		xfree(readset);
1012 	if (writeset)
1013 		xfree(writeset);
1014 
1015 	/* Terminate the session. */
1016 
1017 	/* Stop watching for window change. */
1018 	if (have_pty)
1019 		signal(SIGWINCH, SIG_DFL);
1020 
1021 	channel_free_all();
1022 
1023 	if (have_pty)
1024 		leave_raw_mode();
1025 
1026 	/* restore blocking io */
1027 	if (!isatty(fileno(stdin)))
1028 		unset_nonblock(fileno(stdin));
1029 	if (!isatty(fileno(stdout)))
1030 		unset_nonblock(fileno(stdout));
1031 	if (!isatty(fileno(stderr)))
1032 		unset_nonblock(fileno(stderr));
1033 
1034 	if (received_signal)
1035 		fatal("Killed by signal %d.", (int) received_signal);
1036 
1037 	/*
1038 	 * In interactive mode (with pseudo tty) display a message indicating
1039 	 * that the connection has been closed.
1040 	 */
1041 	if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1042 		snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
1043 		buffer_append(&stderr_buffer, buf, strlen(buf));
1044 	}
1045 
1046 	/* Output any buffered data for stdout. */
1047 	while (buffer_len(&stdout_buffer) > 0) {
1048 		len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1049 		    buffer_len(&stdout_buffer));
1050 		if (len <= 0) {
1051 			error("Write failed flushing stdout buffer.");
1052 			break;
1053 		}
1054 		buffer_consume(&stdout_buffer, len);
1055 		stdout_bytes += len;
1056 	}
1057 
1058 	/* Output any buffered data for stderr. */
1059 	while (buffer_len(&stderr_buffer) > 0) {
1060 		len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1061 		    buffer_len(&stderr_buffer));
1062 		if (len <= 0) {
1063 			error("Write failed flushing stderr buffer.");
1064 			break;
1065 		}
1066 		buffer_consume(&stderr_buffer, len);
1067 		stderr_bytes += len;
1068 	}
1069 
1070 	/* Clear and free any buffers. */
1071 	memset(buf, 0, sizeof(buf));
1072 	buffer_free(&stdin_buffer);
1073 	buffer_free(&stdout_buffer);
1074 	buffer_free(&stderr_buffer);
1075 
1076 	/* Report bytes transferred, and transfer rates. */
1077 	total_time = get_current_time() - start_time;
1078 	debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
1079 	    stdin_bytes, stdout_bytes, stderr_bytes, total_time);
1080 	if (total_time > 0)
1081 		debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
1082 		    stdin_bytes / total_time, stdout_bytes / total_time,
1083 		    stderr_bytes / total_time);
1084 
1085 	/* Return the exit status of the program. */
1086 	debug("Exit status %d", exit_status);
1087 	return exit_status;
1088 }
1089 
1090 /*********/
1091 
1092 static void
1093 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1094 {
1095 	u_int data_len;
1096 	char *data = packet_get_string(&data_len);
1097 	packet_check_eom();
1098 	buffer_append(&stdout_buffer, data, data_len);
1099 	memset(data, 0, data_len);
1100 	xfree(data);
1101 }
1102 static void
1103 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1104 {
1105 	u_int data_len;
1106 	char *data = packet_get_string(&data_len);
1107 	packet_check_eom();
1108 	buffer_append(&stderr_buffer, data, data_len);
1109 	memset(data, 0, data_len);
1110 	xfree(data);
1111 }
1112 static void
1113 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1114 {
1115 	exit_status = packet_get_int();
1116 	packet_check_eom();
1117 	/* Acknowledge the exit. */
1118 	packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1119 	packet_send();
1120 	/*
1121 	 * Must wait for packet to be sent since we are
1122 	 * exiting the loop.
1123 	 */
1124 	packet_write_wait();
1125 	/* Flag that we want to exit. */
1126 	quit_pending = 1;
1127 }
1128 static void
1129 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1130 {
1131 	Channel *c = NULL;
1132 	int remote_id, sock;
1133 
1134 	/* Read the remote channel number from the message. */
1135 	remote_id = packet_get_int();
1136 	packet_check_eom();
1137 
1138 	/*
1139 	 * Get a connection to the local authentication agent (this may again
1140 	 * get forwarded).
1141 	 */
1142 	sock = ssh_get_authentication_socket();
1143 
1144 	/*
1145 	 * If we could not connect the agent, send an error message back to
1146 	 * the server. This should never happen unless the agent dies,
1147 	 * because authentication forwarding is only enabled if we have an
1148 	 * agent.
1149 	 */
1150 	if (sock >= 0) {
1151 		c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1152 		    -1, 0, 0, 0, "authentication agent connection", 1);
1153 		c->remote_id = remote_id;
1154 		c->force_drain = 1;
1155 	}
1156 	if (c == NULL) {
1157 		packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1158 		packet_put_int(remote_id);
1159 	} else {
1160 		/* Send a confirmation to the remote host. */
1161 		debug("Forwarding authentication connection.");
1162 		packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1163 		packet_put_int(remote_id);
1164 		packet_put_int(c->self);
1165 	}
1166 	packet_send();
1167 }
1168 
1169 static Channel *
1170 client_request_forwarded_tcpip(const char *request_type, int rchan)
1171 {
1172 	Channel *c = NULL;
1173 	char *listen_address, *originator_address;
1174 	int listen_port, originator_port;
1175 	int sock;
1176 
1177 	/* Get rest of the packet */
1178 	listen_address = packet_get_string(NULL);
1179 	listen_port = packet_get_int();
1180 	originator_address = packet_get_string(NULL);
1181 	originator_port = packet_get_int();
1182 	packet_check_eom();
1183 
1184 	debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1185 	    listen_address, listen_port, originator_address, originator_port);
1186 
1187 	sock = channel_connect_by_listen_address(listen_port);
1188 	if (sock < 0) {
1189 		xfree(originator_address);
1190 		xfree(listen_address);
1191 		return NULL;
1192 	}
1193 	c = channel_new("forwarded-tcpip",
1194 	    SSH_CHANNEL_CONNECTING, sock, sock, -1,
1195 	    CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1196 	    originator_address, 1);
1197 	xfree(originator_address);
1198 	xfree(listen_address);
1199 	return c;
1200 }
1201 
1202 static Channel *
1203 client_request_x11(const char *request_type, int rchan)
1204 {
1205 	Channel *c = NULL;
1206 	char *originator;
1207 	int originator_port;
1208 	int sock;
1209 
1210 	if (!options.forward_x11) {
1211 		error("Warning: ssh server tried X11 forwarding.");
1212 		error("Warning: this is probably a break in attempt by a malicious server.");
1213 		return NULL;
1214 	}
1215 	originator = packet_get_string(NULL);
1216 	if (datafellows & SSH_BUG_X11FWD) {
1217 		debug2("buggy server: x11 request w/o originator_port");
1218 		originator_port = 0;
1219 	} else {
1220 		originator_port = packet_get_int();
1221 	}
1222 	packet_check_eom();
1223 	/* XXX check permission */
1224 	debug("client_request_x11: request from %s %d", originator,
1225 	    originator_port);
1226 	xfree(originator);
1227 	sock = x11_connect_display();
1228 	if (sock < 0)
1229 		return NULL;
1230 	c = channel_new("x11",
1231 	    SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1232 	    CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1233 	c->force_drain = 1;
1234 	return c;
1235 }
1236 
1237 static Channel *
1238 client_request_agent(const char *request_type, int rchan)
1239 {
1240 	Channel *c = NULL;
1241 	int sock;
1242 
1243 	if (!options.forward_agent) {
1244 		error("Warning: ssh server tried agent forwarding.");
1245 		error("Warning: this is probably a break in attempt by a malicious server.");
1246 		return NULL;
1247 	}
1248 	sock =  ssh_get_authentication_socket();
1249 	if (sock < 0)
1250 		return NULL;
1251 	c = channel_new("authentication agent connection",
1252 	    SSH_CHANNEL_OPEN, sock, sock, -1,
1253 	    CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1254 	    "authentication agent connection", 1);
1255 	c->force_drain = 1;
1256 	return c;
1257 }
1258 
1259 /* XXXX move to generic input handler */
1260 static void
1261 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1262 {
1263 	Channel *c = NULL;
1264 	char *ctype;
1265 	int rchan;
1266 	u_int rmaxpack, rwindow, len;
1267 
1268 	ctype = packet_get_string(&len);
1269 	rchan = packet_get_int();
1270 	rwindow = packet_get_int();
1271 	rmaxpack = packet_get_int();
1272 
1273 	debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1274 	    ctype, rchan, rwindow, rmaxpack);
1275 
1276 	if (strcmp(ctype, "forwarded-tcpip") == 0) {
1277 		c = client_request_forwarded_tcpip(ctype, rchan);
1278 	} else if (strcmp(ctype, "x11") == 0) {
1279 		c = client_request_x11(ctype, rchan);
1280 	} else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1281 		c = client_request_agent(ctype, rchan);
1282 	}
1283 /* XXX duplicate : */
1284 	if (c != NULL) {
1285 		debug("confirm %s", ctype);
1286 		c->remote_id = rchan;
1287 		c->remote_window = rwindow;
1288 		c->remote_maxpacket = rmaxpack;
1289 		if (c->type != SSH_CHANNEL_CONNECTING) {
1290 			packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1291 			packet_put_int(c->remote_id);
1292 			packet_put_int(c->self);
1293 			packet_put_int(c->local_window);
1294 			packet_put_int(c->local_maxpacket);
1295 			packet_send();
1296 		}
1297 	} else {
1298 		debug("failure %s", ctype);
1299 		packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1300 		packet_put_int(rchan);
1301 		packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1302 		if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1303 			packet_put_cstring("open failed");
1304 			packet_put_cstring("");
1305 		}
1306 		packet_send();
1307 	}
1308 	xfree(ctype);
1309 }
1310 static void
1311 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1312 {
1313 	Channel *c = NULL;
1314 	int id, reply, success = 0;
1315 	char *rtype;
1316 
1317 	id = packet_get_int();
1318 	rtype = packet_get_string(NULL);
1319 	reply = packet_get_char();
1320 
1321 	debug("client_input_channel_req: channel %d rtype %s reply %d",
1322 	    id, rtype, reply);
1323 
1324 	if (session_ident == -1) {
1325 		error("client_input_channel_req: no channel %d", session_ident);
1326 	} else if (id != session_ident) {
1327 		error("client_input_channel_req: channel %d: wrong channel: %d",
1328 		    session_ident, id);
1329 	}
1330 	c = channel_lookup(id);
1331 	if (c == NULL) {
1332 		error("client_input_channel_req: channel %d: unknown channel", id);
1333 	} else if (strcmp(rtype, "exit-status") == 0) {
1334 		success = 1;
1335 		exit_status = packet_get_int();
1336 		packet_check_eom();
1337 	}
1338 	if (reply) {
1339 		packet_start(success ?
1340 		    SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1341 		packet_put_int(c->remote_id);
1342 		packet_send();
1343 	}
1344 	xfree(rtype);
1345 }
1346 static void
1347 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1348 {
1349 	char *rtype;
1350 	int want_reply;
1351 	int success = 0;
1352 
1353 	rtype = packet_get_string(NULL);
1354 	want_reply = packet_get_char();
1355 	debug("client_input_global_request: rtype %s want_reply %d", rtype, want_reply);
1356 	if (want_reply) {
1357 		packet_start(success ?
1358 		    SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1359 		packet_send();
1360 		packet_write_wait();
1361 	}
1362 	xfree(rtype);
1363 }
1364 
1365 static void
1366 client_init_dispatch_20(void)
1367 {
1368 	dispatch_init(&dispatch_protocol_error);
1369 
1370 	dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1371 	dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1372 	dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1373 	dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1374 	dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1375 	dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1376 	dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1377 	dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1378 	dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1379 	dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
1380 
1381 	/* rekeying */
1382 	dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1383 
1384 	/* global request reply messages */
1385 	dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
1386 	dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
1387 }
1388 static void
1389 client_init_dispatch_13(void)
1390 {
1391 	dispatch_init(NULL);
1392 	dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1393 	dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1394 	dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1395 	dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1396 	dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1397 	dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1398 	dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1399 	dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1400 	dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1401 
1402 	dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1403 	    &client_input_agent_open : &deny_input_open);
1404 	dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1405 	    &x11_input_open : &deny_input_open);
1406 }
1407 static void
1408 client_init_dispatch_15(void)
1409 {
1410 	client_init_dispatch_13();
1411 	dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1412 	dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1413 }
1414 static void
1415 client_init_dispatch(void)
1416 {
1417 	if (compat20)
1418 		client_init_dispatch_20();
1419 	else if (compat13)
1420 		client_init_dispatch_13();
1421 	else
1422 		client_init_dispatch_15();
1423 }
1424 
1425 /* client specific fatal cleanup */
1426 void
1427 cleanup_exit(int i)
1428 {
1429 	leave_raw_mode();
1430 	leave_non_blocking();
1431 	_exit(i);
1432 }
1433