xref: /freebsd/crypto/openssh/clientloop.c (revision 10b59a9b4add0320d52c15ce057dd697261e7dfc)
1 /* $OpenBSD: clientloop.c,v 1.236 2011/06/22 22:08:42 djm Exp $ */
2 /* $FreeBSD$ */
3 /*
4  * Author: Tatu Ylonen <ylo@cs.hut.fi>
5  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6  *                    All rights reserved
7  * The main loop for the interactive session (client side).
8  *
9  * As far as I am concerned, the code I have written for this software
10  * can be used freely for any purpose.  Any derived versions of this
11  * software must be clearly marked as such, and if the derived work is
12  * incompatible with the protocol description in the RFC file, it must be
13  * called by a name other than "ssh" or "Secure Shell".
14  *
15  *
16  * Copyright (c) 1999 Theo de Raadt.  All rights reserved.
17  *
18  * Redistribution and use in source and binary forms, with or without
19  * modification, are permitted provided that the following conditions
20  * are met:
21  * 1. Redistributions of source code must retain the above copyright
22  *    notice, this list of conditions and the following disclaimer.
23  * 2. Redistributions in binary form must reproduce the above copyright
24  *    notice, this list of conditions and the following disclaimer in the
25  *    documentation and/or other materials provided with the distribution.
26  *
27  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37  *
38  *
39  * SSH2 support added by Markus Friedl.
40  * Copyright (c) 1999, 2000, 2001 Markus Friedl.  All rights reserved.
41  *
42  * Redistribution and use in source and binary forms, with or without
43  * modification, are permitted provided that the following conditions
44  * are met:
45  * 1. Redistributions of source code must retain the above copyright
46  *    notice, this list of conditions and the following disclaimer.
47  * 2. Redistributions in binary form must reproduce the above copyright
48  *    notice, this list of conditions and the following disclaimer in the
49  *    documentation and/or other materials provided with the distribution.
50  *
51  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
52  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
53  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
54  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
55  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
56  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
57  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
58  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
60  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61  */
62 
63 #include "includes.h"
64 
65 #include <sys/types.h>
66 #include <sys/ioctl.h>
67 #include <sys/param.h>
68 #ifdef HAVE_SYS_STAT_H
69 # include <sys/stat.h>
70 #endif
71 #ifdef HAVE_SYS_TIME_H
72 # include <sys/time.h>
73 #endif
74 #include <sys/socket.h>
75 
76 #include <ctype.h>
77 #include <errno.h>
78 #ifdef HAVE_PATHS_H
79 #include <paths.h>
80 #endif
81 #include <signal.h>
82 #include <stdarg.h>
83 #include <stdio.h>
84 #include <stdlib.h>
85 #include <string.h>
86 #include <termios.h>
87 #include <pwd.h>
88 #include <unistd.h>
89 
90 #include "openbsd-compat/sys-queue.h"
91 #include "xmalloc.h"
92 #include "ssh.h"
93 #include "ssh1.h"
94 #include "ssh2.h"
95 #include "packet.h"
96 #include "buffer.h"
97 #include "compat.h"
98 #include "channels.h"
99 #include "dispatch.h"
100 #include "key.h"
101 #include "cipher.h"
102 #include "kex.h"
103 #include "log.h"
104 #include "readconf.h"
105 #include "clientloop.h"
106 #include "sshconnect.h"
107 #include "authfd.h"
108 #include "atomicio.h"
109 #include "sshpty.h"
110 #include "misc.h"
111 #include "match.h"
112 #include "msg.h"
113 #include "roaming.h"
114 
115 /* import options */
116 extern Options options;
117 
118 /* Flag indicating that stdin should be redirected from /dev/null. */
119 extern int stdin_null_flag;
120 
121 /* Flag indicating that no shell has been requested */
122 extern int no_shell_flag;
123 
124 /* Control socket */
125 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
126 
127 /*
128  * Name of the host we are connecting to.  This is the name given on the
129  * command line, or the HostName specified for the user-supplied name in a
130  * configuration file.
131  */
132 extern char *host;
133 
134 /*
135  * Flag to indicate that we have received a window change signal which has
136  * not yet been processed.  This will cause a message indicating the new
137  * window size to be sent to the server a little later.  This is volatile
138  * because this is updated in a signal handler.
139  */
140 static volatile sig_atomic_t received_window_change_signal = 0;
141 static volatile sig_atomic_t received_signal = 0;
142 
143 /* Flag indicating whether the user's terminal is in non-blocking mode. */
144 static int in_non_blocking_mode = 0;
145 
146 /* Time when backgrounded control master using ControlPersist should exit */
147 static time_t control_persist_exit_time = 0;
148 
149 /* Common data for the client loop code. */
150 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
151 static int escape_char1;	/* Escape character. (proto1 only) */
152 static int escape_pending1;	/* Last character was an escape (proto1 only) */
153 static int last_was_cr;		/* Last character was a newline. */
154 static int exit_status;		/* Used to store the command exit status. */
155 static int stdin_eof;		/* EOF has been encountered on stderr. */
156 static Buffer stdin_buffer;	/* Buffer for stdin data. */
157 static Buffer stdout_buffer;	/* Buffer for stdout data. */
158 static Buffer stderr_buffer;	/* Buffer for stderr data. */
159 static u_int buffer_high;	/* Soft max buffer size. */
160 static int connection_in;	/* Connection to server (input). */
161 static int connection_out;	/* Connection to server (output). */
162 static int need_rekeying;	/* Set to non-zero if rekeying is requested. */
163 static int session_closed;	/* In SSH2: login session closed. */
164 static int x11_refuse_time;	/* If >0, refuse x11 opens after this time. */
165 
166 static void client_init_dispatch(void);
167 int	session_ident = -1;
168 
169 int	session_resumed = 0;
170 
171 /* Track escape per proto2 channel */
172 struct escape_filter_ctx {
173 	int escape_pending;
174 	int escape_char;
175 };
176 
177 /* Context for channel confirmation replies */
178 struct channel_reply_ctx {
179 	const char *request_type;
180 	int id;
181 	enum confirm_action action;
182 };
183 
184 /* Global request success/failure callbacks */
185 struct global_confirm {
186 	TAILQ_ENTRY(global_confirm) entry;
187 	global_confirm_cb *cb;
188 	void *ctx;
189 	int ref_count;
190 };
191 TAILQ_HEAD(global_confirms, global_confirm);
192 static struct global_confirms global_confirms =
193     TAILQ_HEAD_INITIALIZER(global_confirms);
194 
195 /*XXX*/
196 extern Kex *xxx_kex;
197 
198 void ssh_process_session2_setup(int, int, int, Buffer *);
199 
200 /* Restores stdin to blocking mode. */
201 
202 static void
203 leave_non_blocking(void)
204 {
205 	if (in_non_blocking_mode) {
206 		unset_nonblock(fileno(stdin));
207 		in_non_blocking_mode = 0;
208 	}
209 }
210 
211 /* Puts stdin terminal in non-blocking mode. */
212 
213 static void
214 enter_non_blocking(void)
215 {
216 	in_non_blocking_mode = 1;
217 	set_nonblock(fileno(stdin));
218 }
219 
220 /*
221  * Signal handler for the window change signal (SIGWINCH).  This just sets a
222  * flag indicating that the window has changed.
223  */
224 /*ARGSUSED */
225 static void
226 window_change_handler(int sig)
227 {
228 	received_window_change_signal = 1;
229 	signal(SIGWINCH, window_change_handler);
230 }
231 
232 /*
233  * Signal handler for signals that cause the program to terminate.  These
234  * signals must be trapped to restore terminal modes.
235  */
236 /*ARGSUSED */
237 static void
238 signal_handler(int sig)
239 {
240 	received_signal = sig;
241 	quit_pending = 1;
242 }
243 
244 /*
245  * Returns current time in seconds from Jan 1, 1970 with the maximum
246  * available resolution.
247  */
248 
249 static double
250 get_current_time(void)
251 {
252 	struct timeval tv;
253 	gettimeofday(&tv, NULL);
254 	return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
255 }
256 
257 /*
258  * Sets control_persist_exit_time to the absolute time when the
259  * backgrounded control master should exit due to expiry of the
260  * ControlPersist timeout.  Sets it to 0 if we are not a backgrounded
261  * control master process, or if there is no ControlPersist timeout.
262  */
263 static void
264 set_control_persist_exit_time(void)
265 {
266 	if (muxserver_sock == -1 || !options.control_persist
267 	    || options.control_persist_timeout == 0) {
268 		/* not using a ControlPersist timeout */
269 		control_persist_exit_time = 0;
270 	} else if (channel_still_open()) {
271 		/* some client connections are still open */
272 		if (control_persist_exit_time > 0)
273 			debug2("%s: cancel scheduled exit", __func__);
274 		control_persist_exit_time = 0;
275 	} else if (control_persist_exit_time <= 0) {
276 		/* a client connection has recently closed */
277 		control_persist_exit_time = time(NULL) +
278 			(time_t)options.control_persist_timeout;
279 		debug2("%s: schedule exit in %d seconds", __func__,
280 		    options.control_persist_timeout);
281 	}
282 	/* else we are already counting down to the timeout */
283 }
284 
285 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
286 void
287 client_x11_get_proto(const char *display, const char *xauth_path,
288     u_int trusted, u_int timeout, char **_proto, char **_data)
289 {
290 	char cmd[1024];
291 	char line[512];
292 	char xdisplay[512];
293 	static char proto[512], data[512];
294 	FILE *f;
295 	int got_data = 0, generated = 0, do_unlink = 0, i;
296 	char *xauthdir, *xauthfile;
297 	struct stat st;
298 	u_int now;
299 
300 	xauthdir = xauthfile = NULL;
301 	*_proto = proto;
302 	*_data = data;
303 	proto[0] = data[0] = '\0';
304 
305 	if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
306 		debug("No xauth program.");
307 	} else {
308 		if (display == NULL) {
309 			debug("x11_get_proto: DISPLAY not set");
310 			return;
311 		}
312 		/*
313 		 * Handle FamilyLocal case where $DISPLAY does
314 		 * not match an authorization entry.  For this we
315 		 * just try "xauth list unix:displaynum.screennum".
316 		 * XXX: "localhost" match to determine FamilyLocal
317 		 *      is not perfect.
318 		 */
319 		if (strncmp(display, "localhost:", 10) == 0) {
320 			snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
321 			    display + 10);
322 			display = xdisplay;
323 		}
324 		if (trusted == 0) {
325 			xauthdir = xmalloc(MAXPATHLEN);
326 			xauthfile = xmalloc(MAXPATHLEN);
327 			mktemp_proto(xauthdir, MAXPATHLEN);
328 			if (mkdtemp(xauthdir) != NULL) {
329 				do_unlink = 1;
330 				snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
331 				    xauthdir);
332 				snprintf(cmd, sizeof(cmd),
333 				    "%s -f %s generate %s " SSH_X11_PROTO
334 				    " untrusted timeout %u 2>" _PATH_DEVNULL,
335 				    xauth_path, xauthfile, display, timeout);
336 				debug2("x11_get_proto: %s", cmd);
337 				if (system(cmd) == 0)
338 					generated = 1;
339 				if (x11_refuse_time == 0) {
340 					now = time(NULL) + 1;
341 					if (UINT_MAX - timeout < now)
342 						x11_refuse_time = UINT_MAX;
343 					else
344 						x11_refuse_time = now + timeout;
345 				}
346 			}
347 		}
348 
349 		/*
350 		 * When in untrusted mode, we read the cookie only if it was
351 		 * successfully generated as an untrusted one in the step
352 		 * above.
353 		 */
354 		if (trusted || generated) {
355 			snprintf(cmd, sizeof(cmd),
356 			    "%s %s%s list %s 2>" _PATH_DEVNULL,
357 			    xauth_path,
358 			    generated ? "-f " : "" ,
359 			    generated ? xauthfile : "",
360 			    display);
361 			debug2("x11_get_proto: %s", cmd);
362 			f = popen(cmd, "r");
363 			if (f && fgets(line, sizeof(line), f) &&
364 			    sscanf(line, "%*s %511s %511s", proto, data) == 2)
365 				got_data = 1;
366 			if (f)
367 				pclose(f);
368 		} else
369 			error("Warning: untrusted X11 forwarding setup failed: "
370 			    "xauth key data not generated");
371 	}
372 
373 	if (do_unlink) {
374 		unlink(xauthfile);
375 		rmdir(xauthdir);
376 	}
377 	if (xauthdir)
378 		xfree(xauthdir);
379 	if (xauthfile)
380 		xfree(xauthfile);
381 
382 	/*
383 	 * If we didn't get authentication data, just make up some
384 	 * data.  The forwarding code will check the validity of the
385 	 * response anyway, and substitute this data.  The X11
386 	 * server, however, will ignore this fake data and use
387 	 * whatever authentication mechanisms it was using otherwise
388 	 * for the local connection.
389 	 */
390 	if (!got_data) {
391 		u_int32_t rnd = 0;
392 
393 		logit("Warning: No xauth data; "
394 		    "using fake authentication data for X11 forwarding.");
395 		strlcpy(proto, SSH_X11_PROTO, sizeof proto);
396 		for (i = 0; i < 16; i++) {
397 			if (i % 4 == 0)
398 				rnd = arc4random();
399 			snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
400 			    rnd & 0xff);
401 			rnd >>= 8;
402 		}
403 	}
404 }
405 
406 /*
407  * This is called when the interactive is entered.  This checks if there is
408  * an EOF coming on stdin.  We must check this explicitly, as select() does
409  * not appear to wake up when redirecting from /dev/null.
410  */
411 
412 static void
413 client_check_initial_eof_on_stdin(void)
414 {
415 	int len;
416 	char buf[1];
417 
418 	/*
419 	 * If standard input is to be "redirected from /dev/null", we simply
420 	 * mark that we have seen an EOF and send an EOF message to the
421 	 * server. Otherwise, we try to read a single character; it appears
422 	 * that for some files, such /dev/null, select() never wakes up for
423 	 * read for this descriptor, which means that we never get EOF.  This
424 	 * way we will get the EOF if stdin comes from /dev/null or similar.
425 	 */
426 	if (stdin_null_flag) {
427 		/* Fake EOF on stdin. */
428 		debug("Sending eof.");
429 		stdin_eof = 1;
430 		packet_start(SSH_CMSG_EOF);
431 		packet_send();
432 	} else {
433 		enter_non_blocking();
434 
435 		/* Check for immediate EOF on stdin. */
436 		len = read(fileno(stdin), buf, 1);
437 		if (len == 0) {
438 			/*
439 			 * EOF.  Record that we have seen it and send
440 			 * EOF to server.
441 			 */
442 			debug("Sending eof.");
443 			stdin_eof = 1;
444 			packet_start(SSH_CMSG_EOF);
445 			packet_send();
446 		} else if (len > 0) {
447 			/*
448 			 * Got data.  We must store the data in the buffer,
449 			 * and also process it as an escape character if
450 			 * appropriate.
451 			 */
452 			if ((u_char) buf[0] == escape_char1)
453 				escape_pending1 = 1;
454 			else
455 				buffer_append(&stdin_buffer, buf, 1);
456 		}
457 		leave_non_blocking();
458 	}
459 }
460 
461 
462 /*
463  * Make packets from buffered stdin data, and buffer them for sending to the
464  * connection.
465  */
466 
467 static void
468 client_make_packets_from_stdin_data(void)
469 {
470 	u_int len;
471 
472 	/* Send buffered stdin data to the server. */
473 	while (buffer_len(&stdin_buffer) > 0 &&
474 	    packet_not_very_much_data_to_write()) {
475 		len = buffer_len(&stdin_buffer);
476 		/* Keep the packets at reasonable size. */
477 		if (len > packet_get_maxsize())
478 			len = packet_get_maxsize();
479 		packet_start(SSH_CMSG_STDIN_DATA);
480 		packet_put_string(buffer_ptr(&stdin_buffer), len);
481 		packet_send();
482 		buffer_consume(&stdin_buffer, len);
483 		/* If we have a pending EOF, send it now. */
484 		if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
485 			packet_start(SSH_CMSG_EOF);
486 			packet_send();
487 		}
488 	}
489 }
490 
491 /*
492  * Checks if the client window has changed, and sends a packet about it to
493  * the server if so.  The actual change is detected elsewhere (by a software
494  * interrupt on Unix); this just checks the flag and sends a message if
495  * appropriate.
496  */
497 
498 static void
499 client_check_window_change(void)
500 {
501 	struct winsize ws;
502 
503 	if (! received_window_change_signal)
504 		return;
505 	/** XXX race */
506 	received_window_change_signal = 0;
507 
508 	debug2("client_check_window_change: changed");
509 
510 	if (compat20) {
511 		channel_send_window_changes();
512 	} else {
513 		if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
514 			return;
515 		packet_start(SSH_CMSG_WINDOW_SIZE);
516 		packet_put_int((u_int)ws.ws_row);
517 		packet_put_int((u_int)ws.ws_col);
518 		packet_put_int((u_int)ws.ws_xpixel);
519 		packet_put_int((u_int)ws.ws_ypixel);
520 		packet_send();
521 	}
522 }
523 
524 static void
525 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
526 {
527 	struct global_confirm *gc;
528 
529 	if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
530 		return;
531 	if (gc->cb != NULL)
532 		gc->cb(type, seq, gc->ctx);
533 	if (--gc->ref_count <= 0) {
534 		TAILQ_REMOVE(&global_confirms, gc, entry);
535 		bzero(gc, sizeof(*gc));
536 		xfree(gc);
537 	}
538 
539 	packet_set_alive_timeouts(0);
540 }
541 
542 static void
543 server_alive_check(void)
544 {
545 	if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
546 		logit("Timeout, server %s not responding.", host);
547 		cleanup_exit(255);
548 	}
549 	packet_start(SSH2_MSG_GLOBAL_REQUEST);
550 	packet_put_cstring("keepalive@openssh.com");
551 	packet_put_char(1);     /* boolean: want reply */
552 	packet_send();
553 	/* Insert an empty placeholder to maintain ordering */
554 	client_register_global_confirm(NULL, NULL);
555 }
556 
557 /*
558  * Waits until the client can do something (some data becomes available on
559  * one of the file descriptors).
560  */
561 static void
562 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
563     int *maxfdp, u_int *nallocp, int rekeying)
564 {
565 	struct timeval tv, *tvp;
566 	int timeout_secs;
567 	int ret;
568 
569 	/* Add any selections by the channel mechanism. */
570 	channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, rekeying);
571 
572 	if (!compat20) {
573 		/* Read from the connection, unless our buffers are full. */
574 		if (buffer_len(&stdout_buffer) < buffer_high &&
575 		    buffer_len(&stderr_buffer) < buffer_high &&
576 		    channel_not_very_much_buffered_data())
577 			FD_SET(connection_in, *readsetp);
578 		/*
579 		 * Read from stdin, unless we have seen EOF or have very much
580 		 * buffered data to send to the server.
581 		 */
582 		if (!stdin_eof && packet_not_very_much_data_to_write())
583 			FD_SET(fileno(stdin), *readsetp);
584 
585 		/* Select stdout/stderr if have data in buffer. */
586 		if (buffer_len(&stdout_buffer) > 0)
587 			FD_SET(fileno(stdout), *writesetp);
588 		if (buffer_len(&stderr_buffer) > 0)
589 			FD_SET(fileno(stderr), *writesetp);
590 	} else {
591 		/* channel_prepare_select could have closed the last channel */
592 		if (session_closed && !channel_still_open() &&
593 		    !packet_have_data_to_write()) {
594 			/* clear mask since we did not call select() */
595 			memset(*readsetp, 0, *nallocp);
596 			memset(*writesetp, 0, *nallocp);
597 			return;
598 		} else {
599 			FD_SET(connection_in, *readsetp);
600 		}
601 	}
602 
603 	/* Select server connection if have data to write to the server. */
604 	if (packet_have_data_to_write())
605 		FD_SET(connection_out, *writesetp);
606 
607 	/*
608 	 * Wait for something to happen.  This will suspend the process until
609 	 * some selected descriptor can be read, written, or has some other
610 	 * event pending, or a timeout expires.
611 	 */
612 
613 	timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
614 	if (options.server_alive_interval > 0 && compat20)
615 		timeout_secs = options.server_alive_interval;
616 	set_control_persist_exit_time();
617 	if (control_persist_exit_time > 0) {
618 		timeout_secs = MIN(timeout_secs,
619 			control_persist_exit_time - time(NULL));
620 		if (timeout_secs < 0)
621 			timeout_secs = 0;
622 	}
623 	if (timeout_secs == INT_MAX)
624 		tvp = NULL;
625 	else {
626 		tv.tv_sec = timeout_secs;
627 		tv.tv_usec = 0;
628 		tvp = &tv;
629 	}
630 
631 	ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
632 	if (ret < 0) {
633 		char buf[100];
634 
635 		/*
636 		 * We have to clear the select masks, because we return.
637 		 * We have to return, because the mainloop checks for the flags
638 		 * set by the signal handlers.
639 		 */
640 		memset(*readsetp, 0, *nallocp);
641 		memset(*writesetp, 0, *nallocp);
642 
643 		if (errno == EINTR)
644 			return;
645 		/* Note: we might still have data in the buffers. */
646 		snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
647 		buffer_append(&stderr_buffer, buf, strlen(buf));
648 		quit_pending = 1;
649 	} else if (ret == 0)
650 		server_alive_check();
651 }
652 
653 static void
654 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
655 {
656 	/* Flush stdout and stderr buffers. */
657 	if (buffer_len(bout) > 0)
658 		atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
659 		    buffer_len(bout));
660 	if (buffer_len(berr) > 0)
661 		atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
662 		    buffer_len(berr));
663 
664 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
665 
666 	/*
667 	 * Free (and clear) the buffer to reduce the amount of data that gets
668 	 * written to swap.
669 	 */
670 	buffer_free(bin);
671 	buffer_free(bout);
672 	buffer_free(berr);
673 
674 	/* Send the suspend signal to the program itself. */
675 	kill(getpid(), SIGTSTP);
676 
677 	/* Reset window sizes in case they have changed */
678 	received_window_change_signal = 1;
679 
680 	/* OK, we have been continued by the user. Reinitialize buffers. */
681 	buffer_init(bin);
682 	buffer_init(bout);
683 	buffer_init(berr);
684 
685 	enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
686 }
687 
688 static void
689 client_process_net_input(fd_set *readset)
690 {
691 	int len, cont = 0;
692 	char buf[SSH_IOBUFSZ];
693 
694 	/*
695 	 * Read input from the server, and add any such data to the buffer of
696 	 * the packet subsystem.
697 	 */
698 	if (FD_ISSET(connection_in, readset)) {
699 		/* Read as much as possible. */
700 		len = roaming_read(connection_in, buf, sizeof(buf), &cont);
701 		if (len == 0 && cont == 0) {
702 			/*
703 			 * Received EOF.  The remote host has closed the
704 			 * connection.
705 			 */
706 			snprintf(buf, sizeof buf,
707 			    "Connection to %.300s closed by remote host.\r\n",
708 			    host);
709 			buffer_append(&stderr_buffer, buf, strlen(buf));
710 			quit_pending = 1;
711 			return;
712 		}
713 		/*
714 		 * There is a kernel bug on Solaris that causes select to
715 		 * sometimes wake up even though there is no data available.
716 		 */
717 		if (len < 0 &&
718 		    (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
719 			len = 0;
720 
721 		if (len < 0) {
722 			/*
723 			 * An error has encountered.  Perhaps there is a
724 			 * network problem.
725 			 */
726 			snprintf(buf, sizeof buf,
727 			    "Read from remote host %.300s: %.100s\r\n",
728 			    host, strerror(errno));
729 			buffer_append(&stderr_buffer, buf, strlen(buf));
730 			quit_pending = 1;
731 			return;
732 		}
733 		packet_process_incoming(buf, len);
734 	}
735 }
736 
737 static void
738 client_status_confirm(int type, Channel *c, void *ctx)
739 {
740 	struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
741 	char errmsg[256];
742 	int tochan;
743 
744 	/*
745 	 * If a TTY was explicitly requested, then a failure to allocate
746 	 * one is fatal.
747 	 */
748 	if (cr->action == CONFIRM_TTY &&
749 	    (options.request_tty == REQUEST_TTY_FORCE ||
750 	    options.request_tty == REQUEST_TTY_YES))
751 		cr->action = CONFIRM_CLOSE;
752 
753 	/* XXX supress on mux _client_ quietmode */
754 	tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
755 	    c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
756 
757 	if (type == SSH2_MSG_CHANNEL_SUCCESS) {
758 		debug2("%s request accepted on channel %d",
759 		    cr->request_type, c->self);
760 	} else if (type == SSH2_MSG_CHANNEL_FAILURE) {
761 		if (tochan) {
762 			snprintf(errmsg, sizeof(errmsg),
763 			    "%s request failed\r\n", cr->request_type);
764 		} else {
765 			snprintf(errmsg, sizeof(errmsg),
766 			    "%s request failed on channel %d",
767 			    cr->request_type, c->self);
768 		}
769 		/* If error occurred on primary session channel, then exit */
770 		if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
771 			fatal("%s", errmsg);
772 		/*
773 		 * If error occurred on mux client, append to
774 		 * their stderr.
775 		 */
776 		if (tochan) {
777 			buffer_append(&c->extended, errmsg,
778 			    strlen(errmsg));
779 		} else
780 			error("%s", errmsg);
781 		if (cr->action == CONFIRM_TTY) {
782 			/*
783 			 * If a TTY allocation error occurred, then arrange
784 			 * for the correct TTY to leave raw mode.
785 			 */
786 			if (c->self == session_ident)
787 				leave_raw_mode(0);
788 			else
789 				mux_tty_alloc_failed(c);
790 		} else if (cr->action == CONFIRM_CLOSE) {
791 			chan_read_failed(c);
792 			chan_write_failed(c);
793 		}
794 	}
795 	xfree(cr);
796 }
797 
798 static void
799 client_abandon_status_confirm(Channel *c, void *ctx)
800 {
801 	xfree(ctx);
802 }
803 
804 void
805 client_expect_confirm(int id, const char *request,
806     enum confirm_action action)
807 {
808 	struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
809 
810 	cr->request_type = request;
811 	cr->action = action;
812 
813 	channel_register_status_confirm(id, client_status_confirm,
814 	    client_abandon_status_confirm, cr);
815 }
816 
817 void
818 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
819 {
820 	struct global_confirm *gc, *last_gc;
821 
822 	/* Coalesce identical callbacks */
823 	last_gc = TAILQ_LAST(&global_confirms, global_confirms);
824 	if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
825 		if (++last_gc->ref_count >= INT_MAX)
826 			fatal("%s: last_gc->ref_count = %d",
827 			    __func__, last_gc->ref_count);
828 		return;
829 	}
830 
831 	gc = xmalloc(sizeof(*gc));
832 	gc->cb = cb;
833 	gc->ctx = ctx;
834 	gc->ref_count = 1;
835 	TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
836 }
837 
838 static void
839 process_cmdline(void)
840 {
841 	void (*handler)(int);
842 	char *s, *cmd, *cancel_host;
843 	int delete = 0;
844 	int local = 0, remote = 0, dynamic = 0;
845 	int cancel_port;
846 	Forward fwd;
847 
848 	bzero(&fwd, sizeof(fwd));
849 	fwd.listen_host = fwd.connect_host = NULL;
850 
851 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
852 	handler = signal(SIGINT, SIG_IGN);
853 	cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
854 	if (s == NULL)
855 		goto out;
856 	while (isspace(*s))
857 		s++;
858 	if (*s == '-')
859 		s++;	/* Skip cmdline '-', if any */
860 	if (*s == '\0')
861 		goto out;
862 
863 	if (*s == 'h' || *s == 'H' || *s == '?') {
864 		logit("Commands:");
865 		logit("      -L[bind_address:]port:host:hostport    "
866 		    "Request local forward");
867 		logit("      -R[bind_address:]port:host:hostport    "
868 		    "Request remote forward");
869 		logit("      -D[bind_address:]port                  "
870 		    "Request dynamic forward");
871 		logit("      -KR[bind_address:]port                 "
872 		    "Cancel remote forward");
873 		if (!options.permit_local_command)
874 			goto out;
875 		logit("      !args                                  "
876 		    "Execute local command");
877 		goto out;
878 	}
879 
880 	if (*s == '!' && options.permit_local_command) {
881 		s++;
882 		ssh_local_cmd(s);
883 		goto out;
884 	}
885 
886 	if (*s == 'K') {
887 		delete = 1;
888 		s++;
889 	}
890 	if (*s == 'L')
891 		local = 1;
892 	else if (*s == 'R')
893 		remote = 1;
894 	else if (*s == 'D')
895 		dynamic = 1;
896 	else {
897 		logit("Invalid command.");
898 		goto out;
899 	}
900 
901 	if ((local || dynamic) && delete) {
902 		logit("Not supported.");
903 		goto out;
904 	}
905 	if (remote && delete && !compat20) {
906 		logit("Not supported for SSH protocol version 1.");
907 		goto out;
908 	}
909 
910 	while (isspace(*++s))
911 		;
912 
913 	/* XXX update list of forwards in options */
914 	if (delete) {
915 		cancel_port = 0;
916 		cancel_host = hpdelim(&s);	/* may be NULL */
917 		if (s != NULL) {
918 			cancel_port = a2port(s);
919 			cancel_host = cleanhostname(cancel_host);
920 		} else {
921 			cancel_port = a2port(cancel_host);
922 			cancel_host = NULL;
923 		}
924 		if (cancel_port <= 0) {
925 			logit("Bad forwarding close port");
926 			goto out;
927 		}
928 		channel_request_rforward_cancel(cancel_host, cancel_port);
929 	} else {
930 		if (!parse_forward(&fwd, s, dynamic, remote)) {
931 			logit("Bad forwarding specification.");
932 			goto out;
933 		}
934 		if (local || dynamic) {
935 			if (channel_setup_local_fwd_listener(fwd.listen_host,
936 			    fwd.listen_port, fwd.connect_host,
937 			    fwd.connect_port, options.gateway_ports) < 0) {
938 				logit("Port forwarding failed.");
939 				goto out;
940 			}
941 		} else {
942 			if (channel_request_remote_forwarding(fwd.listen_host,
943 			    fwd.listen_port, fwd.connect_host,
944 			    fwd.connect_port) < 0) {
945 				logit("Port forwarding failed.");
946 				goto out;
947 			}
948 		}
949 
950 		logit("Forwarding port.");
951 	}
952 
953 out:
954 	signal(SIGINT, handler);
955 	enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
956 	if (cmd)
957 		xfree(cmd);
958 	if (fwd.listen_host != NULL)
959 		xfree(fwd.listen_host);
960 	if (fwd.connect_host != NULL)
961 		xfree(fwd.connect_host);
962 }
963 
964 /*
965  * Process the characters one by one, call with c==NULL for proto1 case.
966  */
967 static int
968 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
969     char *buf, int len)
970 {
971 	char string[1024];
972 	pid_t pid;
973 	int bytes = 0;
974 	u_int i;
975 	u_char ch;
976 	char *s;
977 	int *escape_pendingp, escape_char;
978 	struct escape_filter_ctx *efc;
979 
980 	if (c == NULL) {
981 		escape_pendingp = &escape_pending1;
982 		escape_char = escape_char1;
983 	} else {
984 		if (c->filter_ctx == NULL)
985 			return 0;
986 		efc = (struct escape_filter_ctx *)c->filter_ctx;
987 		escape_pendingp = &efc->escape_pending;
988 		escape_char = efc->escape_char;
989 	}
990 
991 	if (len <= 0)
992 		return (0);
993 
994 	for (i = 0; i < (u_int)len; i++) {
995 		/* Get one character at a time. */
996 		ch = buf[i];
997 
998 		if (*escape_pendingp) {
999 			/* We have previously seen an escape character. */
1000 			/* Clear the flag now. */
1001 			*escape_pendingp = 0;
1002 
1003 			/* Process the escaped character. */
1004 			switch (ch) {
1005 			case '.':
1006 				/* Terminate the connection. */
1007 				snprintf(string, sizeof string, "%c.\r\n",
1008 				    escape_char);
1009 				buffer_append(berr, string, strlen(string));
1010 
1011 				if (c && c->ctl_chan != -1) {
1012 					chan_read_failed(c);
1013 					chan_write_failed(c);
1014 					return 0;
1015 				} else
1016 					quit_pending = 1;
1017 				return -1;
1018 
1019 			case 'Z' - 64:
1020 				/* XXX support this for mux clients */
1021 				if (c && c->ctl_chan != -1) {
1022  noescape:
1023 					snprintf(string, sizeof string,
1024 					    "%c%c escape not available to "
1025 					    "multiplexed sessions\r\n",
1026 					    escape_char, ch);
1027 					buffer_append(berr, string,
1028 					    strlen(string));
1029 					continue;
1030 				}
1031 				/* Suspend the program. Inform the user */
1032 				snprintf(string, sizeof string,
1033 				    "%c^Z [suspend ssh]\r\n", escape_char);
1034 				buffer_append(berr, string, strlen(string));
1035 
1036 				/* Restore terminal modes and suspend. */
1037 				client_suspend_self(bin, bout, berr);
1038 
1039 				/* We have been continued. */
1040 				continue;
1041 
1042 			case 'B':
1043 				if (compat20) {
1044 					snprintf(string, sizeof string,
1045 					    "%cB\r\n", escape_char);
1046 					buffer_append(berr, string,
1047 					    strlen(string));
1048 					channel_request_start(session_ident,
1049 					    "break", 0);
1050 					packet_put_int(1000);
1051 					packet_send();
1052 				}
1053 				continue;
1054 
1055 			case 'R':
1056 				if (compat20) {
1057 					if (datafellows & SSH_BUG_NOREKEY)
1058 						logit("Server does not "
1059 						    "support re-keying");
1060 					else
1061 						need_rekeying = 1;
1062 				}
1063 				continue;
1064 
1065 			case '&':
1066 				if (c && c->ctl_chan != -1)
1067 					goto noescape;
1068 				/*
1069 				 * Detach the program (continue to serve
1070 				 * connections, but put in background and no
1071 				 * more new connections).
1072 				 */
1073 				/* Restore tty modes. */
1074 				leave_raw_mode(
1075 				    options.request_tty == REQUEST_TTY_FORCE);
1076 
1077 				/* Stop listening for new connections. */
1078 				channel_stop_listening();
1079 
1080 				snprintf(string, sizeof string,
1081 				    "%c& [backgrounded]\n", escape_char);
1082 				buffer_append(berr, string, strlen(string));
1083 
1084 				/* Fork into background. */
1085 				pid = fork();
1086 				if (pid < 0) {
1087 					error("fork: %.100s", strerror(errno));
1088 					continue;
1089 				}
1090 				if (pid != 0) {	/* This is the parent. */
1091 					/* The parent just exits. */
1092 					exit(0);
1093 				}
1094 				/* The child continues serving connections. */
1095 				if (compat20) {
1096 					buffer_append(bin, "\004", 1);
1097 					/* fake EOF on stdin */
1098 					return -1;
1099 				} else if (!stdin_eof) {
1100 					/*
1101 					 * Sending SSH_CMSG_EOF alone does not
1102 					 * always appear to be enough.  So we
1103 					 * try to send an EOF character first.
1104 					 */
1105 					packet_start(SSH_CMSG_STDIN_DATA);
1106 					packet_put_string("\004", 1);
1107 					packet_send();
1108 					/* Close stdin. */
1109 					stdin_eof = 1;
1110 					if (buffer_len(bin) == 0) {
1111 						packet_start(SSH_CMSG_EOF);
1112 						packet_send();
1113 					}
1114 				}
1115 				continue;
1116 
1117 			case '?':
1118 				if (c && c->ctl_chan != -1) {
1119 					snprintf(string, sizeof string,
1120 "%c?\r\n\
1121 Supported escape sequences:\r\n\
1122   %c.  - terminate session\r\n\
1123   %cB  - send a BREAK to the remote system\r\n\
1124   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1125   %c#  - list forwarded connections\r\n\
1126   %c?  - this message\r\n\
1127   %c%c  - send the escape character by typing it twice\r\n\
1128 (Note that escapes are only recognized immediately after newline.)\r\n",
1129 					    escape_char, escape_char,
1130 					    escape_char, escape_char,
1131 					    escape_char, escape_char,
1132 					    escape_char, escape_char);
1133 				} else {
1134 					snprintf(string, sizeof string,
1135 "%c?\r\n\
1136 Supported escape sequences:\r\n\
1137   %c.  - terminate connection (and any multiplexed sessions)\r\n\
1138   %cB  - send a BREAK to the remote system\r\n\
1139   %cC  - open a command line\r\n\
1140   %cR  - Request rekey (SSH protocol 2 only)\r\n\
1141   %c^Z - suspend ssh\r\n\
1142   %c#  - list forwarded connections\r\n\
1143   %c&  - background ssh (when waiting for connections to terminate)\r\n\
1144   %c?  - this message\r\n\
1145   %c%c  - send the escape character by typing it twice\r\n\
1146 (Note that escapes are only recognized immediately after newline.)\r\n",
1147 					    escape_char, escape_char,
1148 					    escape_char, escape_char,
1149 					    escape_char, escape_char,
1150 					    escape_char, escape_char,
1151 					    escape_char, escape_char,
1152 					    escape_char);
1153 				}
1154 				buffer_append(berr, string, strlen(string));
1155 				continue;
1156 
1157 			case '#':
1158 				snprintf(string, sizeof string, "%c#\r\n",
1159 				    escape_char);
1160 				buffer_append(berr, string, strlen(string));
1161 				s = channel_open_message();
1162 				buffer_append(berr, s, strlen(s));
1163 				xfree(s);
1164 				continue;
1165 
1166 			case 'C':
1167 				if (c && c->ctl_chan != -1)
1168 					goto noescape;
1169 				process_cmdline();
1170 				continue;
1171 
1172 			default:
1173 				if (ch != escape_char) {
1174 					buffer_put_char(bin, escape_char);
1175 					bytes++;
1176 				}
1177 				/* Escaped characters fall through here */
1178 				break;
1179 			}
1180 		} else {
1181 			/*
1182 			 * The previous character was not an escape char.
1183 			 * Check if this is an escape.
1184 			 */
1185 			if (last_was_cr && ch == escape_char) {
1186 				/*
1187 				 * It is. Set the flag and continue to
1188 				 * next character.
1189 				 */
1190 				*escape_pendingp = 1;
1191 				continue;
1192 			}
1193 		}
1194 
1195 		/*
1196 		 * Normal character.  Record whether it was a newline,
1197 		 * and append it to the buffer.
1198 		 */
1199 		last_was_cr = (ch == '\r' || ch == '\n');
1200 		buffer_put_char(bin, ch);
1201 		bytes++;
1202 	}
1203 	return bytes;
1204 }
1205 
1206 static void
1207 client_process_input(fd_set *readset)
1208 {
1209 	int len;
1210 	char buf[SSH_IOBUFSZ];
1211 
1212 	/* Read input from stdin. */
1213 	if (FD_ISSET(fileno(stdin), readset)) {
1214 		/* Read as much as possible. */
1215 		len = read(fileno(stdin), buf, sizeof(buf));
1216 		if (len < 0 &&
1217 		    (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1218 			return;		/* we'll try again later */
1219 		if (len <= 0) {
1220 			/*
1221 			 * Received EOF or error.  They are treated
1222 			 * similarly, except that an error message is printed
1223 			 * if it was an error condition.
1224 			 */
1225 			if (len < 0) {
1226 				snprintf(buf, sizeof buf, "read: %.100s\r\n",
1227 				    strerror(errno));
1228 				buffer_append(&stderr_buffer, buf, strlen(buf));
1229 			}
1230 			/* Mark that we have seen EOF. */
1231 			stdin_eof = 1;
1232 			/*
1233 			 * Send an EOF message to the server unless there is
1234 			 * data in the buffer.  If there is data in the
1235 			 * buffer, no message will be sent now.  Code
1236 			 * elsewhere will send the EOF when the buffer
1237 			 * becomes empty if stdin_eof is set.
1238 			 */
1239 			if (buffer_len(&stdin_buffer) == 0) {
1240 				packet_start(SSH_CMSG_EOF);
1241 				packet_send();
1242 			}
1243 		} else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1244 			/*
1245 			 * Normal successful read, and no escape character.
1246 			 * Just append the data to buffer.
1247 			 */
1248 			buffer_append(&stdin_buffer, buf, len);
1249 		} else {
1250 			/*
1251 			 * Normal, successful read.  But we have an escape
1252 			 * character and have to process the characters one
1253 			 * by one.
1254 			 */
1255 			if (process_escapes(NULL, &stdin_buffer,
1256 			    &stdout_buffer, &stderr_buffer, buf, len) == -1)
1257 				return;
1258 		}
1259 	}
1260 }
1261 
1262 static void
1263 client_process_output(fd_set *writeset)
1264 {
1265 	int len;
1266 	char buf[100];
1267 
1268 	/* Write buffered output to stdout. */
1269 	if (FD_ISSET(fileno(stdout), writeset)) {
1270 		/* Write as much data as possible. */
1271 		len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1272 		    buffer_len(&stdout_buffer));
1273 		if (len <= 0) {
1274 			if (errno == EINTR || errno == EAGAIN ||
1275 			    errno == EWOULDBLOCK)
1276 				len = 0;
1277 			else {
1278 				/*
1279 				 * An error or EOF was encountered.  Put an
1280 				 * error message to stderr buffer.
1281 				 */
1282 				snprintf(buf, sizeof buf,
1283 				    "write stdout: %.50s\r\n", strerror(errno));
1284 				buffer_append(&stderr_buffer, buf, strlen(buf));
1285 				quit_pending = 1;
1286 				return;
1287 			}
1288 		}
1289 		/* Consume printed data from the buffer. */
1290 		buffer_consume(&stdout_buffer, len);
1291 	}
1292 	/* Write buffered output to stderr. */
1293 	if (FD_ISSET(fileno(stderr), writeset)) {
1294 		/* Write as much data as possible. */
1295 		len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1296 		    buffer_len(&stderr_buffer));
1297 		if (len <= 0) {
1298 			if (errno == EINTR || errno == EAGAIN ||
1299 			    errno == EWOULDBLOCK)
1300 				len = 0;
1301 			else {
1302 				/*
1303 				 * EOF or error, but can't even print
1304 				 * error message.
1305 				 */
1306 				quit_pending = 1;
1307 				return;
1308 			}
1309 		}
1310 		/* Consume printed characters from the buffer. */
1311 		buffer_consume(&stderr_buffer, len);
1312 	}
1313 }
1314 
1315 /*
1316  * Get packets from the connection input buffer, and process them as long as
1317  * there are packets available.
1318  *
1319  * Any unknown packets received during the actual
1320  * session cause the session to terminate.  This is
1321  * intended to make debugging easier since no
1322  * confirmations are sent.  Any compatible protocol
1323  * extensions must be negotiated during the
1324  * preparatory phase.
1325  */
1326 
1327 static void
1328 client_process_buffered_input_packets(void)
1329 {
1330 	dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1331 	    compat20 ? xxx_kex : NULL);
1332 }
1333 
1334 /* scan buf[] for '~' before sending data to the peer */
1335 
1336 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1337 void *
1338 client_new_escape_filter_ctx(int escape_char)
1339 {
1340 	struct escape_filter_ctx *ret;
1341 
1342 	ret = xmalloc(sizeof(*ret));
1343 	ret->escape_pending = 0;
1344 	ret->escape_char = escape_char;
1345 	return (void *)ret;
1346 }
1347 
1348 /* Free the escape filter context on channel free */
1349 void
1350 client_filter_cleanup(int cid, void *ctx)
1351 {
1352 	xfree(ctx);
1353 }
1354 
1355 int
1356 client_simple_escape_filter(Channel *c, char *buf, int len)
1357 {
1358 	if (c->extended_usage != CHAN_EXTENDED_WRITE)
1359 		return 0;
1360 
1361 	return process_escapes(c, &c->input, &c->output, &c->extended,
1362 	    buf, len);
1363 }
1364 
1365 static void
1366 client_channel_closed(int id, void *arg)
1367 {
1368 	channel_cancel_cleanup(id);
1369 	session_closed = 1;
1370 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1371 }
1372 
1373 /*
1374  * Implements the interactive session with the server.  This is called after
1375  * the user has been authenticated, and a command has been started on the
1376  * remote host.  If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1377  * used as an escape character for terminating or suspending the session.
1378  */
1379 
1380 int
1381 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1382 {
1383 	fd_set *readset = NULL, *writeset = NULL;
1384 	double start_time, total_time;
1385 	int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1386 	u_int64_t ibytes, obytes;
1387 	u_int nalloc = 0;
1388 	char buf[100];
1389 
1390 	debug("Entering interactive session.");
1391 
1392 	start_time = get_current_time();
1393 
1394 	/* Initialize variables. */
1395 	escape_pending1 = 0;
1396 	last_was_cr = 1;
1397 	exit_status = -1;
1398 	stdin_eof = 0;
1399 	buffer_high = 64 * 1024;
1400 	connection_in = packet_get_connection_in();
1401 	connection_out = packet_get_connection_out();
1402 	max_fd = MAX(connection_in, connection_out);
1403 
1404 	if (!compat20) {
1405 		/* enable nonblocking unless tty */
1406 		if (!isatty(fileno(stdin)))
1407 			set_nonblock(fileno(stdin));
1408 		if (!isatty(fileno(stdout)))
1409 			set_nonblock(fileno(stdout));
1410 		if (!isatty(fileno(stderr)))
1411 			set_nonblock(fileno(stderr));
1412 		max_fd = MAX(max_fd, fileno(stdin));
1413 		max_fd = MAX(max_fd, fileno(stdout));
1414 		max_fd = MAX(max_fd, fileno(stderr));
1415 	}
1416 	quit_pending = 0;
1417 	escape_char1 = escape_char_arg;
1418 
1419 	/* Initialize buffers. */
1420 	buffer_init(&stdin_buffer);
1421 	buffer_init(&stdout_buffer);
1422 	buffer_init(&stderr_buffer);
1423 
1424 	client_init_dispatch();
1425 
1426 	/*
1427 	 * Set signal handlers, (e.g. to restore non-blocking mode)
1428 	 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1429 	 */
1430 	if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1431 		signal(SIGHUP, signal_handler);
1432 	if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1433 		signal(SIGINT, signal_handler);
1434 	if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1435 		signal(SIGQUIT, signal_handler);
1436 	if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1437 		signal(SIGTERM, signal_handler);
1438 	signal(SIGWINCH, window_change_handler);
1439 
1440 	if (have_pty)
1441 		enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1442 
1443 	if (compat20) {
1444 		session_ident = ssh2_chan_id;
1445 		if (session_ident != -1) {
1446 			if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1447 				channel_register_filter(session_ident,
1448 				    client_simple_escape_filter, NULL,
1449 				    client_filter_cleanup,
1450 				    client_new_escape_filter_ctx(
1451 				    escape_char_arg));
1452 			}
1453 			channel_register_cleanup(session_ident,
1454 			    client_channel_closed, 0);
1455 		}
1456 	} else {
1457 		/* Check if we should immediately send eof on stdin. */
1458 		client_check_initial_eof_on_stdin();
1459 	}
1460 
1461 	/* Main loop of the client for the interactive session mode. */
1462 	while (!quit_pending) {
1463 
1464 		/* Process buffered packets sent by the server. */
1465 		client_process_buffered_input_packets();
1466 
1467 		if (compat20 && session_closed && !channel_still_open())
1468 			break;
1469 
1470 		rekeying = (xxx_kex != NULL && !xxx_kex->done);
1471 
1472 		if (rekeying) {
1473 			debug("rekeying in progress");
1474 		} else {
1475 			/*
1476 			 * Make packets of buffered stdin data, and buffer
1477 			 * them for sending to the server.
1478 			 */
1479 			if (!compat20)
1480 				client_make_packets_from_stdin_data();
1481 
1482 			/*
1483 			 * Make packets from buffered channel data, and
1484 			 * enqueue them for sending to the server.
1485 			 */
1486 			if (packet_not_very_much_data_to_write())
1487 				channel_output_poll();
1488 
1489 			/*
1490 			 * Check if the window size has changed, and buffer a
1491 			 * message about it to the server if so.
1492 			 */
1493 			client_check_window_change();
1494 
1495 			if (quit_pending)
1496 				break;
1497 		}
1498 		/*
1499 		 * Wait until we have something to do (something becomes
1500 		 * available on one of the descriptors).
1501 		 */
1502 		max_fd2 = max_fd;
1503 		client_wait_until_can_do_something(&readset, &writeset,
1504 		    &max_fd2, &nalloc, rekeying);
1505 
1506 		if (quit_pending)
1507 			break;
1508 
1509 		/* Do channel operations unless rekeying in progress. */
1510 		if (!rekeying) {
1511 			channel_after_select(readset, writeset);
1512 			if (need_rekeying || packet_need_rekeying()) {
1513 				debug("need rekeying");
1514 				xxx_kex->done = 0;
1515 				kex_send_kexinit(xxx_kex);
1516 				need_rekeying = 0;
1517 			}
1518 		}
1519 
1520 		/* Buffer input from the connection.  */
1521 		client_process_net_input(readset);
1522 
1523 		if (quit_pending)
1524 			break;
1525 
1526 		if (!compat20) {
1527 			/* Buffer data from stdin */
1528 			client_process_input(readset);
1529 			/*
1530 			 * Process output to stdout and stderr.  Output to
1531 			 * the connection is processed elsewhere (above).
1532 			 */
1533 			client_process_output(writeset);
1534 		}
1535 
1536 		if (session_resumed) {
1537 			connection_in = packet_get_connection_in();
1538 			connection_out = packet_get_connection_out();
1539 			max_fd = MAX(max_fd, connection_out);
1540 			max_fd = MAX(max_fd, connection_in);
1541 			session_resumed = 0;
1542 		}
1543 
1544 		/*
1545 		 * Send as much buffered packet data as possible to the
1546 		 * sender.
1547 		 */
1548 		if (FD_ISSET(connection_out, writeset))
1549 			packet_write_poll();
1550 
1551 		/*
1552 		 * If we are a backgrounded control master, and the
1553 		 * timeout has expired without any active client
1554 		 * connections, then quit.
1555 		 */
1556 		if (control_persist_exit_time > 0) {
1557 			if (time(NULL) >= control_persist_exit_time) {
1558 				debug("ControlPersist timeout expired");
1559 				break;
1560 			}
1561 		}
1562 	}
1563 	if (readset)
1564 		xfree(readset);
1565 	if (writeset)
1566 		xfree(writeset);
1567 
1568 	/* Terminate the session. */
1569 
1570 	/* Stop watching for window change. */
1571 	signal(SIGWINCH, SIG_DFL);
1572 
1573 	if (compat20) {
1574 		packet_start(SSH2_MSG_DISCONNECT);
1575 		packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1576 		packet_put_cstring("disconnected by user");
1577 		packet_put_cstring(""); /* language tag */
1578 		packet_send();
1579 		packet_write_wait();
1580 	}
1581 
1582 	channel_free_all();
1583 
1584 	if (have_pty)
1585 		leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1586 
1587 	/* restore blocking io */
1588 	if (!isatty(fileno(stdin)))
1589 		unset_nonblock(fileno(stdin));
1590 	if (!isatty(fileno(stdout)))
1591 		unset_nonblock(fileno(stdout));
1592 	if (!isatty(fileno(stderr)))
1593 		unset_nonblock(fileno(stderr));
1594 
1595 	/*
1596 	 * If there was no shell or command requested, there will be no remote
1597 	 * exit status to be returned.  In that case, clear error code if the
1598 	 * connection was deliberately terminated at this end.
1599 	 */
1600 	if (no_shell_flag && received_signal == SIGTERM) {
1601 		received_signal = 0;
1602 		exit_status = 0;
1603 	}
1604 
1605 	if (received_signal)
1606 		fatal("Killed by signal %d.", (int) received_signal);
1607 
1608 	/*
1609 	 * In interactive mode (with pseudo tty) display a message indicating
1610 	 * that the connection has been closed.
1611 	 */
1612 	if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1613 		snprintf(buf, sizeof buf,
1614 		    "Connection to %.64s closed.\r\n", host);
1615 		buffer_append(&stderr_buffer, buf, strlen(buf));
1616 	}
1617 
1618 	/* Output any buffered data for stdout. */
1619 	if (buffer_len(&stdout_buffer) > 0) {
1620 		len = atomicio(vwrite, fileno(stdout),
1621 		    buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1622 		if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1623 			error("Write failed flushing stdout buffer.");
1624 		else
1625 			buffer_consume(&stdout_buffer, len);
1626 	}
1627 
1628 	/* Output any buffered data for stderr. */
1629 	if (buffer_len(&stderr_buffer) > 0) {
1630 		len = atomicio(vwrite, fileno(stderr),
1631 		    buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1632 		if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1633 			error("Write failed flushing stderr buffer.");
1634 		else
1635 			buffer_consume(&stderr_buffer, len);
1636 	}
1637 
1638 	/* Clear and free any buffers. */
1639 	memset(buf, 0, sizeof(buf));
1640 	buffer_free(&stdin_buffer);
1641 	buffer_free(&stdout_buffer);
1642 	buffer_free(&stderr_buffer);
1643 
1644 	/* Report bytes transferred, and transfer rates. */
1645 	total_time = get_current_time() - start_time;
1646 	packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1647 	packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1648 	verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1649 	    (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1650 	if (total_time > 0)
1651 		verbose("Bytes per second: sent %.1f, received %.1f",
1652 		    obytes / total_time, ibytes / total_time);
1653 	/* Return the exit status of the program. */
1654 	debug("Exit status %d", exit_status);
1655 	return exit_status;
1656 }
1657 
1658 /*********/
1659 
1660 static void
1661 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1662 {
1663 	u_int data_len;
1664 	char *data = packet_get_string(&data_len);
1665 	packet_check_eom();
1666 	buffer_append(&stdout_buffer, data, data_len);
1667 	memset(data, 0, data_len);
1668 	xfree(data);
1669 }
1670 static void
1671 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1672 {
1673 	u_int data_len;
1674 	char *data = packet_get_string(&data_len);
1675 	packet_check_eom();
1676 	buffer_append(&stderr_buffer, data, data_len);
1677 	memset(data, 0, data_len);
1678 	xfree(data);
1679 }
1680 static void
1681 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1682 {
1683 	exit_status = packet_get_int();
1684 	packet_check_eom();
1685 	/* Acknowledge the exit. */
1686 	packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1687 	packet_send();
1688 	/*
1689 	 * Must wait for packet to be sent since we are
1690 	 * exiting the loop.
1691 	 */
1692 	packet_write_wait();
1693 	/* Flag that we want to exit. */
1694 	quit_pending = 1;
1695 }
1696 static void
1697 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1698 {
1699 	Channel *c = NULL;
1700 	int remote_id, sock;
1701 
1702 	/* Read the remote channel number from the message. */
1703 	remote_id = packet_get_int();
1704 	packet_check_eom();
1705 
1706 	/*
1707 	 * Get a connection to the local authentication agent (this may again
1708 	 * get forwarded).
1709 	 */
1710 	sock = ssh_get_authentication_socket();
1711 
1712 	/*
1713 	 * If we could not connect the agent, send an error message back to
1714 	 * the server. This should never happen unless the agent dies,
1715 	 * because authentication forwarding is only enabled if we have an
1716 	 * agent.
1717 	 */
1718 	if (sock >= 0) {
1719 		c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1720 		    -1, 0, 0, 0, "authentication agent connection", 1);
1721 		c->remote_id = remote_id;
1722 		c->force_drain = 1;
1723 	}
1724 	if (c == NULL) {
1725 		packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1726 		packet_put_int(remote_id);
1727 	} else {
1728 		/* Send a confirmation to the remote host. */
1729 		debug("Forwarding authentication connection.");
1730 		packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1731 		packet_put_int(remote_id);
1732 		packet_put_int(c->self);
1733 	}
1734 	packet_send();
1735 }
1736 
1737 static Channel *
1738 client_request_forwarded_tcpip(const char *request_type, int rchan)
1739 {
1740 	Channel *c = NULL;
1741 	char *listen_address, *originator_address;
1742 	u_short listen_port, originator_port;
1743 
1744 	/* Get rest of the packet */
1745 	listen_address = packet_get_string(NULL);
1746 	listen_port = packet_get_int();
1747 	originator_address = packet_get_string(NULL);
1748 	originator_port = packet_get_int();
1749 	packet_check_eom();
1750 
1751 	debug("client_request_forwarded_tcpip: listen %s port %d, "
1752 	    "originator %s port %d", listen_address, listen_port,
1753 	    originator_address, originator_port);
1754 
1755 	c = channel_connect_by_listen_address(listen_port,
1756 	    "forwarded-tcpip", originator_address);
1757 
1758 	xfree(originator_address);
1759 	xfree(listen_address);
1760 	return c;
1761 }
1762 
1763 static Channel *
1764 client_request_x11(const char *request_type, int rchan)
1765 {
1766 	Channel *c = NULL;
1767 	char *originator;
1768 	u_short originator_port;
1769 	int sock;
1770 
1771 	if (!options.forward_x11) {
1772 		error("Warning: ssh server tried X11 forwarding.");
1773 		error("Warning: this is probably a break-in attempt by a "
1774 		    "malicious server.");
1775 		return NULL;
1776 	}
1777 	if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1778 		verbose("Rejected X11 connection after ForwardX11Timeout "
1779 		    "expired");
1780 		return NULL;
1781 	}
1782 	originator = packet_get_string(NULL);
1783 	if (datafellows & SSH_BUG_X11FWD) {
1784 		debug2("buggy server: x11 request w/o originator_port");
1785 		originator_port = 0;
1786 	} else {
1787 		originator_port = packet_get_int();
1788 	}
1789 	packet_check_eom();
1790 	/* XXX check permission */
1791 	debug("client_request_x11: request from %s %d", originator,
1792 	    originator_port);
1793 	xfree(originator);
1794 	sock = x11_connect_display();
1795 	if (sock < 0)
1796 		return NULL;
1797 	if (options.hpn_disabled)
1798 		c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1799 		    CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1800 		    0, "x11", 1);
1801 	else
1802 		c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1803 		    options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT,
1804 		    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 #if defined(SSH_TUN_FILTER)
1871 	if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1872 		channel_register_filter(c->self, sys_tun_infilter,
1873 		    sys_tun_outfilter, NULL, NULL);
1874 #endif
1875 
1876 	packet_start(SSH2_MSG_CHANNEL_OPEN);
1877 	packet_put_cstring("tun@openssh.com");
1878 	packet_put_int(c->self);
1879 	packet_put_int(c->local_window_max);
1880 	packet_put_int(c->local_maxpacket);
1881 	packet_put_int(tun_mode);
1882 	packet_put_int(remote_tun);
1883 	packet_send();
1884 
1885 	return 0;
1886 }
1887 
1888 /* XXXX move to generic input handler */
1889 static void
1890 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1891 {
1892 	Channel *c = NULL;
1893 	char *ctype;
1894 	int rchan;
1895 	u_int rmaxpack, rwindow, len;
1896 
1897 	ctype = packet_get_string(&len);
1898 	rchan = packet_get_int();
1899 	rwindow = packet_get_int();
1900 	rmaxpack = packet_get_int();
1901 
1902 	debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1903 	    ctype, rchan, rwindow, rmaxpack);
1904 
1905 	if (strcmp(ctype, "forwarded-tcpip") == 0) {
1906 		c = client_request_forwarded_tcpip(ctype, rchan);
1907 	} else if (strcmp(ctype, "x11") == 0) {
1908 		c = client_request_x11(ctype, rchan);
1909 	} else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1910 		c = client_request_agent(ctype, rchan);
1911 	}
1912 /* XXX duplicate : */
1913 	if (c != NULL) {
1914 		debug("confirm %s", ctype);
1915 		c->remote_id = rchan;
1916 		c->remote_window = rwindow;
1917 		c->remote_maxpacket = rmaxpack;
1918 		if (c->type != SSH_CHANNEL_CONNECTING) {
1919 			packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1920 			packet_put_int(c->remote_id);
1921 			packet_put_int(c->self);
1922 			packet_put_int(c->local_window);
1923 			packet_put_int(c->local_maxpacket);
1924 			packet_send();
1925 		}
1926 	} else {
1927 		debug("failure %s", ctype);
1928 		packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1929 		packet_put_int(rchan);
1930 		packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1931 		if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1932 			packet_put_cstring("open failed");
1933 			packet_put_cstring("");
1934 		}
1935 		packet_send();
1936 	}
1937 	xfree(ctype);
1938 }
1939 static void
1940 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1941 {
1942 	Channel *c = NULL;
1943 	int exitval, id, reply, success = 0;
1944 	char *rtype;
1945 
1946 	id = packet_get_int();
1947 	rtype = packet_get_string(NULL);
1948 	reply = packet_get_char();
1949 
1950 	debug("client_input_channel_req: channel %d rtype %s reply %d",
1951 	    id, rtype, reply);
1952 
1953 	if (id == -1) {
1954 		error("client_input_channel_req: request for channel -1");
1955 	} else if ((c = channel_lookup(id)) == NULL) {
1956 		error("client_input_channel_req: channel %d: "
1957 		    "unknown channel", id);
1958 	} else if (strcmp(rtype, "eow@openssh.com") == 0) {
1959 		packet_check_eom();
1960 		chan_rcvd_eow(c);
1961 	} else if (strcmp(rtype, "exit-status") == 0) {
1962 		exitval = packet_get_int();
1963 		if (c->ctl_chan != -1) {
1964 			mux_exit_message(c, exitval);
1965 			success = 1;
1966 		} else if (id == session_ident) {
1967 			/* Record exit value of local session */
1968 			success = 1;
1969 			exit_status = exitval;
1970 		} else {
1971 			/* Probably for a mux channel that has already closed */
1972 			debug("%s: no sink for exit-status on channel %d",
1973 			    __func__, id);
1974 		}
1975 		packet_check_eom();
1976 	}
1977 	if (reply && c != NULL) {
1978 		packet_start(success ?
1979 		    SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1980 		packet_put_int(c->remote_id);
1981 		packet_send();
1982 	}
1983 	xfree(rtype);
1984 }
1985 static void
1986 client_input_global_request(int type, u_int32_t seq, void *ctxt)
1987 {
1988 	char *rtype;
1989 	int want_reply;
1990 	int success = 0;
1991 
1992 	rtype = packet_get_string(NULL);
1993 	want_reply = packet_get_char();
1994 	debug("client_input_global_request: rtype %s want_reply %d",
1995 	    rtype, want_reply);
1996 	if (want_reply) {
1997 		packet_start(success ?
1998 		    SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1999 		packet_send();
2000 		packet_write_wait();
2001 	}
2002 	xfree(rtype);
2003 }
2004 
2005 void
2006 client_session2_setup(int id, int want_tty, int want_subsystem,
2007     const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2008 {
2009 	int len;
2010 	Channel *c = NULL;
2011 
2012 	debug2("%s: id %d", __func__, id);
2013 
2014 	if ((c = channel_lookup(id)) == NULL)
2015 		fatal("client_session2_setup: channel %d: unknown channel", id);
2016 
2017 	packet_set_interactive(want_tty,
2018 	    options.ip_qos_interactive, options.ip_qos_bulk);
2019 
2020 	if (want_tty) {
2021 		struct winsize ws;
2022 
2023 		/* Store window size in the packet. */
2024 		if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2025 			memset(&ws, 0, sizeof(ws));
2026 
2027 		channel_request_start(id, "pty-req", 1);
2028 		client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2029 		packet_put_cstring(term != NULL ? term : "");
2030 		packet_put_int((u_int)ws.ws_col);
2031 		packet_put_int((u_int)ws.ws_row);
2032 		packet_put_int((u_int)ws.ws_xpixel);
2033 		packet_put_int((u_int)ws.ws_ypixel);
2034 		if (tiop == NULL)
2035 			tiop = get_saved_tio();
2036 		tty_make_modes(-1, tiop);
2037 		packet_send();
2038 		/* XXX wait for reply */
2039 		c->client_tty = 1;
2040 	}
2041 
2042 	/* Transfer any environment variables from client to server */
2043 	if (options.num_send_env != 0 && env != NULL) {
2044 		int i, j, matched;
2045 		char *name, *val;
2046 
2047 		debug("Sending environment.");
2048 		for (i = 0; env[i] != NULL; i++) {
2049 			/* Split */
2050 			name = xstrdup(env[i]);
2051 			if ((val = strchr(name, '=')) == NULL) {
2052 				xfree(name);
2053 				continue;
2054 			}
2055 			*val++ = '\0';
2056 
2057 			matched = 0;
2058 			for (j = 0; j < options.num_send_env; j++) {
2059 				if (match_pattern(name, options.send_env[j])) {
2060 					matched = 1;
2061 					break;
2062 				}
2063 			}
2064 			if (!matched) {
2065 				debug3("Ignored env %s", name);
2066 				xfree(name);
2067 				continue;
2068 			}
2069 
2070 			debug("Sending env %s = %s", name, val);
2071 			channel_request_start(id, "env", 0);
2072 			packet_put_cstring(name);
2073 			packet_put_cstring(val);
2074 			packet_send();
2075 			xfree(name);
2076 		}
2077 	}
2078 
2079 	len = buffer_len(cmd);
2080 	if (len > 0) {
2081 		if (len > 900)
2082 			len = 900;
2083 		if (want_subsystem) {
2084 			debug("Sending subsystem: %.*s",
2085 			    len, (u_char*)buffer_ptr(cmd));
2086 			channel_request_start(id, "subsystem", 1);
2087 			client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2088 		} else {
2089 			debug("Sending command: %.*s",
2090 			    len, (u_char*)buffer_ptr(cmd));
2091 			channel_request_start(id, "exec", 1);
2092 			client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2093 		}
2094 		packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2095 		packet_send();
2096 	} else {
2097 		channel_request_start(id, "shell", 1);
2098 		client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2099 		packet_send();
2100 	}
2101 }
2102 
2103 static void
2104 client_init_dispatch_20(void)
2105 {
2106 	dispatch_init(&dispatch_protocol_error);
2107 
2108 	dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2109 	dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2110 	dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2111 	dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2112 	dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2113 	dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2114 	dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2115 	dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2116 	dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2117 	dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2118 	dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2119 	dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2120 
2121 	/* rekeying */
2122 	dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2123 
2124 	/* global request reply messages */
2125 	dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2126 	dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2127 }
2128 
2129 static void
2130 client_init_dispatch_13(void)
2131 {
2132 	dispatch_init(NULL);
2133 	dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2134 	dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2135 	dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2136 	dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2137 	dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2138 	dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2139 	dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2140 	dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2141 	dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2142 
2143 	dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2144 	    &client_input_agent_open : &deny_input_open);
2145 	dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2146 	    &x11_input_open : &deny_input_open);
2147 }
2148 
2149 static void
2150 client_init_dispatch_15(void)
2151 {
2152 	client_init_dispatch_13();
2153 	dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2154 	dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2155 }
2156 
2157 static void
2158 client_init_dispatch(void)
2159 {
2160 	if (compat20)
2161 		client_init_dispatch_20();
2162 	else if (compat13)
2163 		client_init_dispatch_13();
2164 	else
2165 		client_init_dispatch_15();
2166 }
2167 
2168 void
2169 client_stop_mux(void)
2170 {
2171 	if (options.control_path != NULL && muxserver_sock != -1)
2172 		unlink(options.control_path);
2173 	/*
2174 	 * If we are in persist mode, signal that we should close when all
2175 	 * active channels are closed.
2176 	 */
2177 	if (options.control_persist) {
2178 		session_closed = 1;
2179 		setproctitle("[stopped mux]");
2180 	}
2181 }
2182 
2183 /* client specific fatal cleanup */
2184 void
2185 cleanup_exit(int i)
2186 {
2187 	leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2188 	leave_non_blocking();
2189 	if (options.control_path != NULL && muxserver_sock != -1)
2190 		unlink(options.control_path);
2191 	ssh_kill_proxy_command();
2192 	_exit(i);
2193 }
2194