1 /* $OpenBSD: clientloop.c,v 1.240 2012/06/20 04:42:58 djm Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * The main loop for the interactive session (client side).
8 * As far as I am concerned, the code I have written for this software
9 * can be used freely for any purpose. Any derived versions of this
10 * software must be clearly marked as such, and if the derived work is
11 * incompatible with the protocol description in the RFC file, it must be
12 * called by a name other than "ssh" or "Secure Shell".
15 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
20 * 1. Redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution.
26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
38 * SSH2 support added by Markus Friedl.
39 * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
41 * Redistribution and use in source and binary forms, with or without
42 * modification, are permitted provided that the following conditions
44 * 1. Redistributions of source code must retain the above copyright
45 * notice, this list of conditions and the following disclaimer.
46 * 2. Redistributions in binary form must reproduce the above copyright
47 * notice, this list of conditions and the following disclaimer in the
48 * documentation and/or other materials provided with the distribution.
50 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
51 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
52 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
53 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
54 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
55 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
56 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
57 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
58 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
59 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
64 #include <sys/types.h>
65 #include <sys/ioctl.h>
66 #include <sys/param.h>
67 #ifdef HAVE_SYS_STAT_H
68 # include <sys/stat.h>
70 #ifdef HAVE_SYS_TIME_H
71 # include <sys/time.h>
73 #include <sys/socket.h>
89 #include "openbsd-compat/sys-queue.h"
103 #include "readconf.h"
104 #include "clientloop.h"
105 #include "sshconnect.h"
107 #include "atomicio.h"
115 extern Options options;
117 /* Flag indicating that stdin should be redirected from /dev/null. */
118 extern int stdin_null_flag;
120 /* Flag indicating that no shell has been requested */
121 extern int no_shell_flag;
124 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
127 * Name of the host we are connecting to. This is the name given on the
128 * command line, or the HostName specified for the user-supplied name in a
129 * configuration file.
134 * Flag to indicate that we have received a window change signal which has
135 * not yet been processed. This will cause a message indicating the new
136 * window size to be sent to the server a little later. This is volatile
137 * because this is updated in a signal handler.
139 static volatile sig_atomic_t received_window_change_signal = 0;
140 static volatile sig_atomic_t received_signal = 0;
142 /* Flag indicating whether the user's terminal is in non-blocking mode. */
143 static int in_non_blocking_mode = 0;
145 /* Time when backgrounded control master using ControlPersist should exit */
146 static time_t control_persist_exit_time = 0;
148 /* Common data for the client loop code. */
149 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
150 static int escape_char1; /* Escape character. (proto1 only) */
151 static int escape_pending1; /* Last character was an escape (proto1 only) */
152 static int last_was_cr; /* Last character was a newline. */
153 static int exit_status; /* Used to store the command exit status. */
154 static int stdin_eof; /* EOF has been encountered on stderr. */
155 static Buffer stdin_buffer; /* Buffer for stdin data. */
156 static Buffer stdout_buffer; /* Buffer for stdout data. */
157 static Buffer stderr_buffer; /* Buffer for stderr data. */
158 static u_int buffer_high; /* Soft max buffer size. */
159 static int connection_in; /* Connection to server (input). */
160 static int connection_out; /* Connection to server (output). */
161 static int need_rekeying; /* Set to non-zero if rekeying is requested. */
162 static int session_closed; /* In SSH2: login session closed. */
163 static int x11_refuse_time; /* If >0, refuse x11 opens after this time. */
165 static void client_init_dispatch(void);
166 int session_ident = -1;
168 int session_resumed = 0;
170 /* Track escape per proto2 channel */
171 struct escape_filter_ctx {
176 /* Context for channel confirmation replies */
177 struct channel_reply_ctx {
178 const char *request_type;
180 enum confirm_action action;
183 /* Global request success/failure callbacks */
184 struct global_confirm {
185 TAILQ_ENTRY(global_confirm) entry;
186 global_confirm_cb *cb;
190 TAILQ_HEAD(global_confirms, global_confirm);
191 static struct global_confirms global_confirms =
192 TAILQ_HEAD_INITIALIZER(global_confirms);
197 void ssh_process_session2_setup(int, int, int, Buffer *);
199 /* Restores stdin to blocking mode. */
202 leave_non_blocking(void)
204 if (in_non_blocking_mode) {
205 unset_nonblock(fileno(stdin));
206 in_non_blocking_mode = 0;
210 /* Puts stdin terminal in non-blocking mode. */
213 enter_non_blocking(void)
215 in_non_blocking_mode = 1;
216 set_nonblock(fileno(stdin));
220 * Signal handler for the window change signal (SIGWINCH). This just sets a
221 * flag indicating that the window has changed.
225 window_change_handler(int sig)
227 received_window_change_signal = 1;
228 signal(SIGWINCH, window_change_handler);
232 * Signal handler for signals that cause the program to terminate. These
233 * signals must be trapped to restore terminal modes.
237 signal_handler(int sig)
239 received_signal = sig;
244 * Returns current time in seconds from Jan 1, 1970 with the maximum
245 * available resolution.
249 get_current_time(void)
252 gettimeofday(&tv, NULL);
253 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
257 * Sets control_persist_exit_time to the absolute time when the
258 * backgrounded control master should exit due to expiry of the
259 * ControlPersist timeout. Sets it to 0 if we are not a backgrounded
260 * control master process, or if there is no ControlPersist timeout.
263 set_control_persist_exit_time(void)
265 if (muxserver_sock == -1 || !options.control_persist
266 || options.control_persist_timeout == 0) {
267 /* not using a ControlPersist timeout */
268 control_persist_exit_time = 0;
269 } else if (channel_still_open()) {
270 /* some client connections are still open */
271 if (control_persist_exit_time > 0)
272 debug2("%s: cancel scheduled exit", __func__);
273 control_persist_exit_time = 0;
274 } else if (control_persist_exit_time <= 0) {
275 /* a client connection has recently closed */
276 control_persist_exit_time = time(NULL) +
277 (time_t)options.control_persist_timeout;
278 debug2("%s: schedule exit in %d seconds", __func__,
279 options.control_persist_timeout);
281 /* else we are already counting down to the timeout */
284 #define SSH_X11_VALID_DISPLAY_CHARS ":/.-_"
286 client_x11_display_valid(const char *display)
290 dlen = strlen(display);
291 for (i = 0; i < dlen; i++) {
292 if (!isalnum(display[i]) &&
293 strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) {
294 debug("Invalid character '%c' in DISPLAY", display[i]);
301 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
303 client_x11_get_proto(const char *display, const char *xauth_path,
304 u_int trusted, u_int timeout, char **_proto, char **_data)
309 static char proto[512], data[512];
311 int got_data = 0, generated = 0, do_unlink = 0, i;
312 char *xauthdir, *xauthfile;
316 xauthdir = xauthfile = NULL;
319 proto[0] = data[0] = '\0';
321 if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
322 debug("No xauth program.");
323 } else if (!client_x11_display_valid(display)) {
324 logit("DISPLAY '%s' invalid, falling back to fake xauth data",
327 if (display == NULL) {
328 debug("x11_get_proto: DISPLAY not set");
332 * Handle FamilyLocal case where $DISPLAY does
333 * not match an authorization entry. For this we
334 * just try "xauth list unix:displaynum.screennum".
335 * XXX: "localhost" match to determine FamilyLocal
338 if (strncmp(display, "localhost:", 10) == 0) {
339 snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
344 xauthdir = xmalloc(MAXPATHLEN);
345 xauthfile = xmalloc(MAXPATHLEN);
346 mktemp_proto(xauthdir, MAXPATHLEN);
347 if (mkdtemp(xauthdir) != NULL) {
349 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
351 snprintf(cmd, sizeof(cmd),
352 "%s -f %s generate %s " SSH_X11_PROTO
353 " untrusted timeout %u 2>" _PATH_DEVNULL,
354 xauth_path, xauthfile, display, timeout);
355 debug2("x11_get_proto: %s", cmd);
356 if (system(cmd) == 0)
358 if (x11_refuse_time == 0) {
359 now = time(NULL) + 1;
360 if (UINT_MAX - timeout < now)
361 x11_refuse_time = UINT_MAX;
363 x11_refuse_time = now + timeout;
369 * When in untrusted mode, we read the cookie only if it was
370 * successfully generated as an untrusted one in the step
373 if (trusted || generated) {
374 snprintf(cmd, sizeof(cmd),
375 "%s %s%s list %s 2>" _PATH_DEVNULL,
377 generated ? "-f " : "" ,
378 generated ? xauthfile : "",
380 debug2("x11_get_proto: %s", cmd);
382 if (f && fgets(line, sizeof(line), f) &&
383 sscanf(line, "%*s %511s %511s", proto, data) == 2)
388 error("Warning: untrusted X11 forwarding setup failed: "
389 "xauth key data not generated");
402 * If we didn't get authentication data, just make up some
403 * data. The forwarding code will check the validity of the
404 * response anyway, and substitute this data. The X11
405 * server, however, will ignore this fake data and use
406 * whatever authentication mechanisms it was using otherwise
407 * for the local connection.
412 logit("Warning: No xauth data; "
413 "using fake authentication data for X11 forwarding.");
414 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
415 for (i = 0; i < 16; i++) {
418 snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
426 * This is called when the interactive is entered. This checks if there is
427 * an EOF coming on stdin. We must check this explicitly, as select() does
428 * not appear to wake up when redirecting from /dev/null.
432 client_check_initial_eof_on_stdin(void)
438 * If standard input is to be "redirected from /dev/null", we simply
439 * mark that we have seen an EOF and send an EOF message to the
440 * server. Otherwise, we try to read a single character; it appears
441 * that for some files, such /dev/null, select() never wakes up for
442 * read for this descriptor, which means that we never get EOF. This
443 * way we will get the EOF if stdin comes from /dev/null or similar.
445 if (stdin_null_flag) {
446 /* Fake EOF on stdin. */
447 debug("Sending eof.");
449 packet_start(SSH_CMSG_EOF);
452 enter_non_blocking();
454 /* Check for immediate EOF on stdin. */
455 len = read(fileno(stdin), buf, 1);
458 * EOF. Record that we have seen it and send
461 debug("Sending eof.");
463 packet_start(SSH_CMSG_EOF);
465 } else if (len > 0) {
467 * Got data. We must store the data in the buffer,
468 * and also process it as an escape character if
471 if ((u_char) buf[0] == escape_char1)
474 buffer_append(&stdin_buffer, buf, 1);
476 leave_non_blocking();
482 * Make packets from buffered stdin data, and buffer them for sending to the
487 client_make_packets_from_stdin_data(void)
491 /* Send buffered stdin data to the server. */
492 while (buffer_len(&stdin_buffer) > 0 &&
493 packet_not_very_much_data_to_write()) {
494 len = buffer_len(&stdin_buffer);
495 /* Keep the packets at reasonable size. */
496 if (len > packet_get_maxsize())
497 len = packet_get_maxsize();
498 packet_start(SSH_CMSG_STDIN_DATA);
499 packet_put_string(buffer_ptr(&stdin_buffer), len);
501 buffer_consume(&stdin_buffer, len);
502 /* If we have a pending EOF, send it now. */
503 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
504 packet_start(SSH_CMSG_EOF);
511 * Checks if the client window has changed, and sends a packet about it to
512 * the server if so. The actual change is detected elsewhere (by a software
513 * interrupt on Unix); this just checks the flag and sends a message if
518 client_check_window_change(void)
522 if (! received_window_change_signal)
525 received_window_change_signal = 0;
527 debug2("client_check_window_change: changed");
530 channel_send_window_changes();
532 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
534 packet_start(SSH_CMSG_WINDOW_SIZE);
535 packet_put_int((u_int)ws.ws_row);
536 packet_put_int((u_int)ws.ws_col);
537 packet_put_int((u_int)ws.ws_xpixel);
538 packet_put_int((u_int)ws.ws_ypixel);
544 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
546 struct global_confirm *gc;
548 if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
551 gc->cb(type, seq, gc->ctx);
552 if (--gc->ref_count <= 0) {
553 TAILQ_REMOVE(&global_confirms, gc, entry);
554 bzero(gc, sizeof(*gc));
558 packet_set_alive_timeouts(0);
562 server_alive_check(void)
564 if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
565 logit("Timeout, server %s not responding.", host);
568 packet_start(SSH2_MSG_GLOBAL_REQUEST);
569 packet_put_cstring("keepalive@openssh.com");
570 packet_put_char(1); /* boolean: want reply */
572 /* Insert an empty placeholder to maintain ordering */
573 client_register_global_confirm(NULL, NULL);
577 * Waits until the client can do something (some data becomes available on
578 * one of the file descriptors).
581 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
582 int *maxfdp, u_int *nallocp, int rekeying)
584 struct timeval tv, *tvp;
586 time_t minwait_secs = 0;
589 /* Add any selections by the channel mechanism. */
590 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp,
591 &minwait_secs, rekeying);
594 /* Read from the connection, unless our buffers are full. */
595 if (buffer_len(&stdout_buffer) < buffer_high &&
596 buffer_len(&stderr_buffer) < buffer_high &&
597 channel_not_very_much_buffered_data())
598 FD_SET(connection_in, *readsetp);
600 * Read from stdin, unless we have seen EOF or have very much
601 * buffered data to send to the server.
603 if (!stdin_eof && packet_not_very_much_data_to_write())
604 FD_SET(fileno(stdin), *readsetp);
606 /* Select stdout/stderr if have data in buffer. */
607 if (buffer_len(&stdout_buffer) > 0)
608 FD_SET(fileno(stdout), *writesetp);
609 if (buffer_len(&stderr_buffer) > 0)
610 FD_SET(fileno(stderr), *writesetp);
612 /* channel_prepare_select could have closed the last channel */
613 if (session_closed && !channel_still_open() &&
614 !packet_have_data_to_write()) {
615 /* clear mask since we did not call select() */
616 memset(*readsetp, 0, *nallocp);
617 memset(*writesetp, 0, *nallocp);
620 FD_SET(connection_in, *readsetp);
624 /* Select server connection if have data to write to the server. */
625 if (packet_have_data_to_write())
626 FD_SET(connection_out, *writesetp);
629 * Wait for something to happen. This will suspend the process until
630 * some selected descriptor can be read, written, or has some other
631 * event pending, or a timeout expires.
634 timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
635 if (options.server_alive_interval > 0 && compat20)
636 timeout_secs = options.server_alive_interval;
637 set_control_persist_exit_time();
638 if (control_persist_exit_time > 0) {
639 timeout_secs = MIN(timeout_secs,
640 control_persist_exit_time - time(NULL));
641 if (timeout_secs < 0)
644 if (minwait_secs != 0)
645 timeout_secs = MIN(timeout_secs, (int)minwait_secs);
646 if (timeout_secs == INT_MAX)
649 tv.tv_sec = timeout_secs;
654 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
659 * We have to clear the select masks, because we return.
660 * We have to return, because the mainloop checks for the flags
661 * set by the signal handlers.
663 memset(*readsetp, 0, *nallocp);
664 memset(*writesetp, 0, *nallocp);
668 /* Note: we might still have data in the buffers. */
669 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
670 buffer_append(&stderr_buffer, buf, strlen(buf));
673 server_alive_check();
677 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
679 /* Flush stdout and stderr buffers. */
680 if (buffer_len(bout) > 0)
681 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
683 if (buffer_len(berr) > 0)
684 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
687 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
690 * Free (and clear) the buffer to reduce the amount of data that gets
697 /* Send the suspend signal to the program itself. */
698 kill(getpid(), SIGTSTP);
700 /* Reset window sizes in case they have changed */
701 received_window_change_signal = 1;
703 /* OK, we have been continued by the user. Reinitialize buffers. */
708 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
712 client_process_net_input(fd_set *readset)
715 char buf[SSH_IOBUFSZ];
718 * Read input from the server, and add any such data to the buffer of
719 * the packet subsystem.
721 if (FD_ISSET(connection_in, readset)) {
722 /* Read as much as possible. */
723 len = roaming_read(connection_in, buf, sizeof(buf), &cont);
724 if (len == 0 && cont == 0) {
726 * Received EOF. The remote host has closed the
729 snprintf(buf, sizeof buf,
730 "Connection to %.300s closed by remote host.\r\n",
732 buffer_append(&stderr_buffer, buf, strlen(buf));
737 * There is a kernel bug on Solaris that causes select to
738 * sometimes wake up even though there is no data available.
741 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
746 * An error has encountered. Perhaps there is a
749 snprintf(buf, sizeof buf,
750 "Read from remote host %.300s: %.100s\r\n",
751 host, strerror(errno));
752 buffer_append(&stderr_buffer, buf, strlen(buf));
756 packet_process_incoming(buf, len);
761 client_status_confirm(int type, Channel *c, void *ctx)
763 struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
768 * If a TTY was explicitly requested, then a failure to allocate
771 if (cr->action == CONFIRM_TTY &&
772 (options.request_tty == REQUEST_TTY_FORCE ||
773 options.request_tty == REQUEST_TTY_YES))
774 cr->action = CONFIRM_CLOSE;
776 /* XXX supress on mux _client_ quietmode */
777 tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
778 c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
780 if (type == SSH2_MSG_CHANNEL_SUCCESS) {
781 debug2("%s request accepted on channel %d",
782 cr->request_type, c->self);
783 } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
785 snprintf(errmsg, sizeof(errmsg),
786 "%s request failed\r\n", cr->request_type);
788 snprintf(errmsg, sizeof(errmsg),
789 "%s request failed on channel %d",
790 cr->request_type, c->self);
792 /* If error occurred on primary session channel, then exit */
793 if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
796 * If error occurred on mux client, append to
800 buffer_append(&c->extended, errmsg,
804 if (cr->action == CONFIRM_TTY) {
806 * If a TTY allocation error occurred, then arrange
807 * for the correct TTY to leave raw mode.
809 if (c->self == session_ident)
812 mux_tty_alloc_failed(c);
813 } else if (cr->action == CONFIRM_CLOSE) {
815 chan_write_failed(c);
822 client_abandon_status_confirm(Channel *c, void *ctx)
828 client_expect_confirm(int id, const char *request,
829 enum confirm_action action)
831 struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
833 cr->request_type = request;
836 channel_register_status_confirm(id, client_status_confirm,
837 client_abandon_status_confirm, cr);
841 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
843 struct global_confirm *gc, *last_gc;
845 /* Coalesce identical callbacks */
846 last_gc = TAILQ_LAST(&global_confirms, global_confirms);
847 if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
848 if (++last_gc->ref_count >= INT_MAX)
849 fatal("%s: last_gc->ref_count = %d",
850 __func__, last_gc->ref_count);
854 gc = xmalloc(sizeof(*gc));
858 TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
862 process_cmdline(void)
864 void (*handler)(int);
865 char *s, *cmd, *cancel_host;
866 int delete = 0, local = 0, remote = 0, dynamic = 0;
870 bzero(&fwd, sizeof(fwd));
871 fwd.listen_host = fwd.connect_host = NULL;
873 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
874 handler = signal(SIGINT, SIG_IGN);
875 cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
881 s++; /* Skip cmdline '-', if any */
885 if (*s == 'h' || *s == 'H' || *s == '?') {
887 logit(" -L[bind_address:]port:host:hostport "
888 "Request local forward");
889 logit(" -R[bind_address:]port:host:hostport "
890 "Request remote forward");
891 logit(" -D[bind_address:]port "
892 "Request dynamic forward");
893 logit(" -KL[bind_address:]port "
894 "Cancel local forward");
895 logit(" -KR[bind_address:]port "
896 "Cancel remote forward");
897 logit(" -KD[bind_address:]port "
898 "Cancel dynamic forward");
899 if (!options.permit_local_command)
902 "Execute local command");
906 if (*s == '!' && options.permit_local_command) {
923 logit("Invalid command.");
927 if (delete && !compat20) {
928 logit("Not supported for SSH protocol version 1.");
932 while (isspace(*++s))
935 /* XXX update list of forwards in options */
938 cancel_host = hpdelim(&s); /* may be NULL */
940 cancel_port = a2port(s);
941 cancel_host = cleanhostname(cancel_host);
943 cancel_port = a2port(cancel_host);
946 if (cancel_port <= 0) {
947 logit("Bad forwarding close port");
951 ok = channel_request_rforward_cancel(cancel_host,
954 ok = channel_cancel_lport_listener(cancel_host,
955 cancel_port, 0, options.gateway_ports) > 0;
957 ok = channel_cancel_lport_listener(cancel_host,
958 cancel_port, CHANNEL_CANCEL_PORT_STATIC,
959 options.gateway_ports) > 0;
961 logit("Unkown port forwarding.");
964 logit("Canceled forwarding.");
966 if (!parse_forward(&fwd, s, dynamic, remote)) {
967 logit("Bad forwarding specification.");
970 if (local || dynamic) {
971 if (channel_setup_local_fwd_listener(fwd.listen_host,
972 fwd.listen_port, fwd.connect_host,
973 fwd.connect_port, options.gateway_ports) < 0) {
974 logit("Port forwarding failed.");
978 if (channel_request_remote_forwarding(fwd.listen_host,
979 fwd.listen_port, fwd.connect_host,
980 fwd.connect_port) < 0) {
981 logit("Port forwarding failed.");
985 logit("Forwarding port.");
989 signal(SIGINT, handler);
990 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
993 if (fwd.listen_host != NULL)
994 xfree(fwd.listen_host);
995 if (fwd.connect_host != NULL)
996 xfree(fwd.connect_host);
1000 * Process the characters one by one, call with c==NULL for proto1 case.
1003 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
1012 int *escape_pendingp, escape_char;
1013 struct escape_filter_ctx *efc;
1016 escape_pendingp = &escape_pending1;
1017 escape_char = escape_char1;
1019 if (c->filter_ctx == NULL)
1021 efc = (struct escape_filter_ctx *)c->filter_ctx;
1022 escape_pendingp = &efc->escape_pending;
1023 escape_char = efc->escape_char;
1029 for (i = 0; i < (u_int)len; i++) {
1030 /* Get one character at a time. */
1033 if (*escape_pendingp) {
1034 /* We have previously seen an escape character. */
1035 /* Clear the flag now. */
1036 *escape_pendingp = 0;
1038 /* Process the escaped character. */
1041 /* Terminate the connection. */
1042 snprintf(string, sizeof string, "%c.\r\n",
1044 buffer_append(berr, string, strlen(string));
1046 if (c && c->ctl_chan != -1) {
1047 chan_read_failed(c);
1048 chan_write_failed(c);
1055 /* XXX support this for mux clients */
1056 if (c && c->ctl_chan != -1) {
1058 snprintf(string, sizeof string,
1059 "%c%c escape not available to "
1060 "multiplexed sessions\r\n",
1062 buffer_append(berr, string,
1066 /* Suspend the program. Inform the user */
1067 snprintf(string, sizeof string,
1068 "%c^Z [suspend ssh]\r\n", escape_char);
1069 buffer_append(berr, string, strlen(string));
1071 /* Restore terminal modes and suspend. */
1072 client_suspend_self(bin, bout, berr);
1074 /* We have been continued. */
1079 snprintf(string, sizeof string,
1080 "%cB\r\n", escape_char);
1081 buffer_append(berr, string,
1083 channel_request_start(session_ident,
1085 packet_put_int(1000);
1092 if (datafellows & SSH_BUG_NOREKEY)
1093 logit("Server does not "
1094 "support re-keying");
1101 if (c && c->ctl_chan != -1)
1104 * Detach the program (continue to serve
1105 * connections, but put in background and no
1106 * more new connections).
1108 /* Restore tty modes. */
1110 options.request_tty == REQUEST_TTY_FORCE);
1112 /* Stop listening for new connections. */
1113 channel_stop_listening();
1115 snprintf(string, sizeof string,
1116 "%c& [backgrounded]\n", escape_char);
1117 buffer_append(berr, string, strlen(string));
1119 /* Fork into background. */
1122 error("fork: %.100s", strerror(errno));
1125 if (pid != 0) { /* This is the parent. */
1126 /* The parent just exits. */
1129 /* The child continues serving connections. */
1131 buffer_append(bin, "\004", 1);
1132 /* fake EOF on stdin */
1134 } else if (!stdin_eof) {
1136 * Sending SSH_CMSG_EOF alone does not
1137 * always appear to be enough. So we
1138 * try to send an EOF character first.
1140 packet_start(SSH_CMSG_STDIN_DATA);
1141 packet_put_string("\004", 1);
1145 if (buffer_len(bin) == 0) {
1146 packet_start(SSH_CMSG_EOF);
1153 if (c && c->ctl_chan != -1) {
1154 snprintf(string, sizeof string,
1156 Supported escape sequences:\r\n\
1157 %c. - terminate session\r\n\
1158 %cB - send a BREAK to the remote system\r\n\
1159 %cR - Request rekey (SSH protocol 2 only)\r\n\
1160 %c# - list forwarded connections\r\n\
1161 %c? - this message\r\n\
1162 %c%c - send the escape character by typing it twice\r\n\
1163 (Note that escapes are only recognized immediately after newline.)\r\n",
1164 escape_char, escape_char,
1165 escape_char, escape_char,
1166 escape_char, escape_char,
1167 escape_char, escape_char);
1169 snprintf(string, sizeof string,
1171 Supported escape sequences:\r\n\
1172 %c. - terminate connection (and any multiplexed sessions)\r\n\
1173 %cB - send a BREAK to the remote system\r\n\
1174 %cC - open a command line\r\n\
1175 %cR - Request rekey (SSH protocol 2 only)\r\n\
1176 %c^Z - suspend ssh\r\n\
1177 %c# - list forwarded connections\r\n\
1178 %c& - background ssh (when waiting for connections to terminate)\r\n\
1179 %c? - this message\r\n\
1180 %c%c - send the escape character by typing it twice\r\n\
1181 (Note that escapes are only recognized immediately after newline.)\r\n",
1182 escape_char, escape_char,
1183 escape_char, escape_char,
1184 escape_char, escape_char,
1185 escape_char, escape_char,
1186 escape_char, escape_char,
1189 buffer_append(berr, string, strlen(string));
1193 snprintf(string, sizeof string, "%c#\r\n",
1195 buffer_append(berr, string, strlen(string));
1196 s = channel_open_message();
1197 buffer_append(berr, s, strlen(s));
1202 if (c && c->ctl_chan != -1)
1208 if (ch != escape_char) {
1209 buffer_put_char(bin, escape_char);
1212 /* Escaped characters fall through here */
1217 * The previous character was not an escape char.
1218 * Check if this is an escape.
1220 if (last_was_cr && ch == escape_char) {
1222 * It is. Set the flag and continue to
1225 *escape_pendingp = 1;
1231 * Normal character. Record whether it was a newline,
1232 * and append it to the buffer.
1234 last_was_cr = (ch == '\r' || ch == '\n');
1235 buffer_put_char(bin, ch);
1242 client_process_input(fd_set *readset)
1245 char buf[SSH_IOBUFSZ];
1247 /* Read input from stdin. */
1248 if (FD_ISSET(fileno(stdin), readset)) {
1249 /* Read as much as possible. */
1250 len = read(fileno(stdin), buf, sizeof(buf));
1252 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1253 return; /* we'll try again later */
1256 * Received EOF or error. They are treated
1257 * similarly, except that an error message is printed
1258 * if it was an error condition.
1261 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1263 buffer_append(&stderr_buffer, buf, strlen(buf));
1265 /* Mark that we have seen EOF. */
1268 * Send an EOF message to the server unless there is
1269 * data in the buffer. If there is data in the
1270 * buffer, no message will be sent now. Code
1271 * elsewhere will send the EOF when the buffer
1272 * becomes empty if stdin_eof is set.
1274 if (buffer_len(&stdin_buffer) == 0) {
1275 packet_start(SSH_CMSG_EOF);
1278 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1280 * Normal successful read, and no escape character.
1281 * Just append the data to buffer.
1283 buffer_append(&stdin_buffer, buf, len);
1286 * Normal, successful read. But we have an escape
1287 * character and have to process the characters one
1290 if (process_escapes(NULL, &stdin_buffer,
1291 &stdout_buffer, &stderr_buffer, buf, len) == -1)
1298 client_process_output(fd_set *writeset)
1303 /* Write buffered output to stdout. */
1304 if (FD_ISSET(fileno(stdout), writeset)) {
1305 /* Write as much data as possible. */
1306 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1307 buffer_len(&stdout_buffer));
1309 if (errno == EINTR || errno == EAGAIN ||
1310 errno == EWOULDBLOCK)
1314 * An error or EOF was encountered. Put an
1315 * error message to stderr buffer.
1317 snprintf(buf, sizeof buf,
1318 "write stdout: %.50s\r\n", strerror(errno));
1319 buffer_append(&stderr_buffer, buf, strlen(buf));
1324 /* Consume printed data from the buffer. */
1325 buffer_consume(&stdout_buffer, len);
1327 /* Write buffered output to stderr. */
1328 if (FD_ISSET(fileno(stderr), writeset)) {
1329 /* Write as much data as possible. */
1330 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1331 buffer_len(&stderr_buffer));
1333 if (errno == EINTR || errno == EAGAIN ||
1334 errno == EWOULDBLOCK)
1338 * EOF or error, but can't even print
1345 /* Consume printed characters from the buffer. */
1346 buffer_consume(&stderr_buffer, len);
1351 * Get packets from the connection input buffer, and process them as long as
1352 * there are packets available.
1354 * Any unknown packets received during the actual
1355 * session cause the session to terminate. This is
1356 * intended to make debugging easier since no
1357 * confirmations are sent. Any compatible protocol
1358 * extensions must be negotiated during the
1359 * preparatory phase.
1363 client_process_buffered_input_packets(void)
1365 dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1366 compat20 ? xxx_kex : NULL);
1369 /* scan buf[] for '~' before sending data to the peer */
1371 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1373 client_new_escape_filter_ctx(int escape_char)
1375 struct escape_filter_ctx *ret;
1377 ret = xmalloc(sizeof(*ret));
1378 ret->escape_pending = 0;
1379 ret->escape_char = escape_char;
1383 /* Free the escape filter context on channel free */
1385 client_filter_cleanup(int cid, void *ctx)
1391 client_simple_escape_filter(Channel *c, char *buf, int len)
1393 if (c->extended_usage != CHAN_EXTENDED_WRITE)
1396 return process_escapes(c, &c->input, &c->output, &c->extended,
1401 client_channel_closed(int id, void *arg)
1403 channel_cancel_cleanup(id);
1405 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1409 * Implements the interactive session with the server. This is called after
1410 * the user has been authenticated, and a command has been started on the
1411 * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1412 * used as an escape character for terminating or suspending the session.
1416 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1418 fd_set *readset = NULL, *writeset = NULL;
1419 double start_time, total_time;
1420 int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1421 u_int64_t ibytes, obytes;
1425 debug("Entering interactive session.");
1427 start_time = get_current_time();
1429 /* Initialize variables. */
1430 escape_pending1 = 0;
1434 buffer_high = 64 * 1024;
1435 connection_in = packet_get_connection_in();
1436 connection_out = packet_get_connection_out();
1437 max_fd = MAX(connection_in, connection_out);
1440 /* enable nonblocking unless tty */
1441 if (!isatty(fileno(stdin)))
1442 set_nonblock(fileno(stdin));
1443 if (!isatty(fileno(stdout)))
1444 set_nonblock(fileno(stdout));
1445 if (!isatty(fileno(stderr)))
1446 set_nonblock(fileno(stderr));
1447 max_fd = MAX(max_fd, fileno(stdin));
1448 max_fd = MAX(max_fd, fileno(stdout));
1449 max_fd = MAX(max_fd, fileno(stderr));
1452 escape_char1 = escape_char_arg;
1454 /* Initialize buffers. */
1455 buffer_init(&stdin_buffer);
1456 buffer_init(&stdout_buffer);
1457 buffer_init(&stderr_buffer);
1459 client_init_dispatch();
1462 * Set signal handlers, (e.g. to restore non-blocking mode)
1463 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1465 if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1466 signal(SIGHUP, signal_handler);
1467 if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1468 signal(SIGINT, signal_handler);
1469 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1470 signal(SIGQUIT, signal_handler);
1471 if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1472 signal(SIGTERM, signal_handler);
1473 signal(SIGWINCH, window_change_handler);
1476 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1479 session_ident = ssh2_chan_id;
1480 if (session_ident != -1) {
1481 if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1482 channel_register_filter(session_ident,
1483 client_simple_escape_filter, NULL,
1484 client_filter_cleanup,
1485 client_new_escape_filter_ctx(
1488 channel_register_cleanup(session_ident,
1489 client_channel_closed, 0);
1492 /* Check if we should immediately send eof on stdin. */
1493 client_check_initial_eof_on_stdin();
1496 /* Main loop of the client for the interactive session mode. */
1497 while (!quit_pending) {
1499 /* Process buffered packets sent by the server. */
1500 client_process_buffered_input_packets();
1502 if (compat20 && session_closed && !channel_still_open())
1505 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1508 debug("rekeying in progress");
1511 * Make packets of buffered stdin data, and buffer
1512 * them for sending to the server.
1515 client_make_packets_from_stdin_data();
1518 * Make packets from buffered channel data, and
1519 * enqueue them for sending to the server.
1521 if (packet_not_very_much_data_to_write())
1522 channel_output_poll();
1525 * Check if the window size has changed, and buffer a
1526 * message about it to the server if so.
1528 client_check_window_change();
1534 * Wait until we have something to do (something becomes
1535 * available on one of the descriptors).
1538 client_wait_until_can_do_something(&readset, &writeset,
1539 &max_fd2, &nalloc, rekeying);
1544 /* Do channel operations unless rekeying in progress. */
1546 channel_after_select(readset, writeset);
1547 if (need_rekeying || packet_need_rekeying()) {
1548 debug("need rekeying");
1550 kex_send_kexinit(xxx_kex);
1555 /* Buffer input from the connection. */
1556 client_process_net_input(readset);
1562 /* Buffer data from stdin */
1563 client_process_input(readset);
1565 * Process output to stdout and stderr. Output to
1566 * the connection is processed elsewhere (above).
1568 client_process_output(writeset);
1571 if (session_resumed) {
1572 connection_in = packet_get_connection_in();
1573 connection_out = packet_get_connection_out();
1574 max_fd = MAX(max_fd, connection_out);
1575 max_fd = MAX(max_fd, connection_in);
1576 session_resumed = 0;
1580 * Send as much buffered packet data as possible to the
1583 if (FD_ISSET(connection_out, writeset))
1584 packet_write_poll();
1587 * If we are a backgrounded control master, and the
1588 * timeout has expired without any active client
1589 * connections, then quit.
1591 if (control_persist_exit_time > 0) {
1592 if (time(NULL) >= control_persist_exit_time) {
1593 debug("ControlPersist timeout expired");
1603 /* Terminate the session. */
1605 /* Stop watching for window change. */
1606 signal(SIGWINCH, SIG_DFL);
1609 packet_start(SSH2_MSG_DISCONNECT);
1610 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1611 packet_put_cstring("disconnected by user");
1612 packet_put_cstring(""); /* language tag */
1614 packet_write_wait();
1620 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1622 /* restore blocking io */
1623 if (!isatty(fileno(stdin)))
1624 unset_nonblock(fileno(stdin));
1625 if (!isatty(fileno(stdout)))
1626 unset_nonblock(fileno(stdout));
1627 if (!isatty(fileno(stderr)))
1628 unset_nonblock(fileno(stderr));
1631 * If there was no shell or command requested, there will be no remote
1632 * exit status to be returned. In that case, clear error code if the
1633 * connection was deliberately terminated at this end.
1635 if (no_shell_flag && received_signal == SIGTERM) {
1636 received_signal = 0;
1640 if (received_signal)
1641 fatal("Killed by signal %d.", (int) received_signal);
1644 * In interactive mode (with pseudo tty) display a message indicating
1645 * that the connection has been closed.
1647 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1648 snprintf(buf, sizeof buf,
1649 "Connection to %.64s closed.\r\n", host);
1650 buffer_append(&stderr_buffer, buf, strlen(buf));
1653 /* Output any buffered data for stdout. */
1654 if (buffer_len(&stdout_buffer) > 0) {
1655 len = atomicio(vwrite, fileno(stdout),
1656 buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1657 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1658 error("Write failed flushing stdout buffer.");
1660 buffer_consume(&stdout_buffer, len);
1663 /* Output any buffered data for stderr. */
1664 if (buffer_len(&stderr_buffer) > 0) {
1665 len = atomicio(vwrite, fileno(stderr),
1666 buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1667 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1668 error("Write failed flushing stderr buffer.");
1670 buffer_consume(&stderr_buffer, len);
1673 /* Clear and free any buffers. */
1674 memset(buf, 0, sizeof(buf));
1675 buffer_free(&stdin_buffer);
1676 buffer_free(&stdout_buffer);
1677 buffer_free(&stderr_buffer);
1679 /* Report bytes transferred, and transfer rates. */
1680 total_time = get_current_time() - start_time;
1681 packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1682 packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1683 verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1684 (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1686 verbose("Bytes per second: sent %.1f, received %.1f",
1687 obytes / total_time, ibytes / total_time);
1688 /* Return the exit status of the program. */
1689 debug("Exit status %d", exit_status);
1696 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1699 char *data = packet_get_string(&data_len);
1701 buffer_append(&stdout_buffer, data, data_len);
1702 memset(data, 0, data_len);
1706 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1709 char *data = packet_get_string(&data_len);
1711 buffer_append(&stderr_buffer, data, data_len);
1712 memset(data, 0, data_len);
1716 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1718 exit_status = packet_get_int();
1720 /* Acknowledge the exit. */
1721 packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1724 * Must wait for packet to be sent since we are
1727 packet_write_wait();
1728 /* Flag that we want to exit. */
1732 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1735 int remote_id, sock;
1737 /* Read the remote channel number from the message. */
1738 remote_id = packet_get_int();
1742 * Get a connection to the local authentication agent (this may again
1745 sock = ssh_get_authentication_socket();
1748 * If we could not connect the agent, send an error message back to
1749 * the server. This should never happen unless the agent dies,
1750 * because authentication forwarding is only enabled if we have an
1754 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1755 -1, 0, 0, 0, "authentication agent connection", 1);
1756 c->remote_id = remote_id;
1760 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1761 packet_put_int(remote_id);
1763 /* Send a confirmation to the remote host. */
1764 debug("Forwarding authentication connection.");
1765 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1766 packet_put_int(remote_id);
1767 packet_put_int(c->self);
1773 client_request_forwarded_tcpip(const char *request_type, int rchan)
1776 char *listen_address, *originator_address;
1777 u_short listen_port, originator_port;
1779 /* Get rest of the packet */
1780 listen_address = packet_get_string(NULL);
1781 listen_port = packet_get_int();
1782 originator_address = packet_get_string(NULL);
1783 originator_port = packet_get_int();
1786 debug("client_request_forwarded_tcpip: listen %s port %d, "
1787 "originator %s port %d", listen_address, listen_port,
1788 originator_address, originator_port);
1790 c = channel_connect_by_listen_address(listen_port,
1791 "forwarded-tcpip", originator_address);
1793 xfree(originator_address);
1794 xfree(listen_address);
1799 client_request_x11(const char *request_type, int rchan)
1803 u_short originator_port;
1806 if (!options.forward_x11) {
1807 error("Warning: ssh server tried X11 forwarding.");
1808 error("Warning: this is probably a break-in attempt by a "
1809 "malicious server.");
1812 if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1813 verbose("Rejected X11 connection after ForwardX11Timeout "
1817 originator = packet_get_string(NULL);
1818 if (datafellows & SSH_BUG_X11FWD) {
1819 debug2("buggy server: x11 request w/o originator_port");
1820 originator_port = 0;
1822 originator_port = packet_get_int();
1825 /* XXX check permission */
1826 debug("client_request_x11: request from %s %d", originator,
1829 sock = x11_connect_display();
1832 /* again is this really necessary for X11? */
1833 if (options.hpn_disabled)
1834 c = channel_new("x11",
1835 SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1836 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1838 c = channel_new("x11",
1839 SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1840 options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1846 client_request_agent(const char *request_type, int rchan)
1851 if (!options.forward_agent) {
1852 error("Warning: ssh server tried agent forwarding.");
1853 error("Warning: this is probably a break-in attempt by a "
1854 "malicious server.");
1857 sock = ssh_get_authentication_socket();
1860 if (options.hpn_disabled)
1861 c = channel_new("authentication agent connection",
1862 SSH_CHANNEL_OPEN, sock, sock, -1,
1863 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1864 "authentication agent connection", 1);
1866 c = channel_new("authentication agent connection",
1867 SSH_CHANNEL_OPEN, sock, sock, -1,
1868 options.hpn_buffer_size, options.hpn_buffer_size, 0,
1869 "authentication agent connection", 1);
1875 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1880 if (tun_mode == SSH_TUNMODE_NO)
1884 error("Tunnel forwarding is not supported for protocol 1");
1888 debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1890 /* Open local tunnel device */
1891 if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1892 error("Tunnel device open failed.");
1896 if(options.hpn_disabled)
1897 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1898 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1901 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1902 options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
1908 #if defined(SSH_TUN_FILTER)
1909 if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1910 channel_register_filter(c->self, sys_tun_infilter,
1911 sys_tun_outfilter, NULL, NULL);
1914 packet_start(SSH2_MSG_CHANNEL_OPEN);
1915 packet_put_cstring("tun@openssh.com");
1916 packet_put_int(c->self);
1917 packet_put_int(c->local_window_max);
1918 packet_put_int(c->local_maxpacket);
1919 packet_put_int(tun_mode);
1920 packet_put_int(remote_tun);
1926 /* XXXX move to generic input handler */
1928 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1933 u_int rmaxpack, rwindow, len;
1935 ctype = packet_get_string(&len);
1936 rchan = packet_get_int();
1937 rwindow = packet_get_int();
1938 rmaxpack = packet_get_int();
1940 debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1941 ctype, rchan, rwindow, rmaxpack);
1943 if (strcmp(ctype, "forwarded-tcpip") == 0) {
1944 c = client_request_forwarded_tcpip(ctype, rchan);
1945 } else if (strcmp(ctype, "x11") == 0) {
1946 c = client_request_x11(ctype, rchan);
1947 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1948 c = client_request_agent(ctype, rchan);
1950 /* XXX duplicate : */
1952 debug("confirm %s", ctype);
1953 c->remote_id = rchan;
1954 c->remote_window = rwindow;
1955 c->remote_maxpacket = rmaxpack;
1956 if (c->type != SSH_CHANNEL_CONNECTING) {
1957 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1958 packet_put_int(c->remote_id);
1959 packet_put_int(c->self);
1960 packet_put_int(c->local_window);
1961 packet_put_int(c->local_maxpacket);
1965 debug("failure %s", ctype);
1966 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1967 packet_put_int(rchan);
1968 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1969 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1970 packet_put_cstring("open failed");
1971 packet_put_cstring("");
1978 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1981 int exitval, id, reply, success = 0;
1984 id = packet_get_int();
1985 rtype = packet_get_string(NULL);
1986 reply = packet_get_char();
1988 debug("client_input_channel_req: channel %d rtype %s reply %d",
1992 error("client_input_channel_req: request for channel -1");
1993 } else if ((c = channel_lookup(id)) == NULL) {
1994 error("client_input_channel_req: channel %d: "
1995 "unknown channel", id);
1996 } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1999 } else if (strcmp(rtype, "exit-status") == 0) {
2000 exitval = packet_get_int();
2001 if (c->ctl_chan != -1) {
2002 mux_exit_message(c, exitval);
2004 } else if (id == session_ident) {
2005 /* Record exit value of local session */
2007 exit_status = exitval;
2009 /* Probably for a mux channel that has already closed */
2010 debug("%s: no sink for exit-status on channel %d",
2015 if (reply && c != NULL) {
2016 packet_start(success ?
2017 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
2018 packet_put_int(c->remote_id);
2024 client_input_global_request(int type, u_int32_t seq, void *ctxt)
2030 rtype = packet_get_string(NULL);
2031 want_reply = packet_get_char();
2032 debug("client_input_global_request: rtype %s want_reply %d",
2035 packet_start(success ?
2036 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2038 packet_write_wait();
2044 client_session2_setup(int id, int want_tty, int want_subsystem,
2045 const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2050 debug2("%s: id %d", __func__, id);
2052 if ((c = channel_lookup(id)) == NULL)
2053 fatal("client_session2_setup: channel %d: unknown channel", id);
2055 packet_set_interactive(want_tty,
2056 options.ip_qos_interactive, options.ip_qos_bulk);
2061 /* Store window size in the packet. */
2062 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2063 memset(&ws, 0, sizeof(ws));
2065 channel_request_start(id, "pty-req", 1);
2066 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2067 packet_put_cstring(term != NULL ? term : "");
2068 packet_put_int((u_int)ws.ws_col);
2069 packet_put_int((u_int)ws.ws_row);
2070 packet_put_int((u_int)ws.ws_xpixel);
2071 packet_put_int((u_int)ws.ws_ypixel);
2073 tiop = get_saved_tio();
2074 tty_make_modes(-1, tiop);
2076 /* XXX wait for reply */
2080 /* Transfer any environment variables from client to server */
2081 if (options.num_send_env != 0 && env != NULL) {
2085 debug("Sending environment.");
2086 for (i = 0; env[i] != NULL; i++) {
2088 name = xstrdup(env[i]);
2089 if ((val = strchr(name, '=')) == NULL) {
2096 for (j = 0; j < options.num_send_env; j++) {
2097 if (match_pattern(name, options.send_env[j])) {
2103 debug3("Ignored env %s", name);
2108 debug("Sending env %s = %s", name, val);
2109 channel_request_start(id, "env", 0);
2110 packet_put_cstring(name);
2111 packet_put_cstring(val);
2117 len = buffer_len(cmd);
2121 if (want_subsystem) {
2122 debug("Sending subsystem: %.*s",
2123 len, (u_char*)buffer_ptr(cmd));
2124 channel_request_start(id, "subsystem", 1);
2125 client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2127 debug("Sending command: %.*s",
2128 len, (u_char*)buffer_ptr(cmd));
2129 channel_request_start(id, "exec", 1);
2130 client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2132 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2135 channel_request_start(id, "shell", 1);
2136 client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2142 client_init_dispatch_20(void)
2144 dispatch_init(&dispatch_protocol_error);
2146 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2147 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2148 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2149 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2150 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2151 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2152 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2153 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2154 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2155 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2156 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2157 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2160 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2162 /* global request reply messages */
2163 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2164 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2168 client_init_dispatch_13(void)
2170 dispatch_init(NULL);
2171 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2172 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2173 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2174 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2175 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2176 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2177 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2178 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2179 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2181 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2182 &client_input_agent_open : &deny_input_open);
2183 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2184 &x11_input_open : &deny_input_open);
2188 client_init_dispatch_15(void)
2190 client_init_dispatch_13();
2191 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2192 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2196 client_init_dispatch(void)
2199 client_init_dispatch_20();
2201 client_init_dispatch_13();
2203 client_init_dispatch_15();
2207 client_stop_mux(void)
2209 if (options.control_path != NULL && muxserver_sock != -1)
2210 unlink(options.control_path);
2212 * If we are in persist mode, signal that we should close when all
2213 * active channels are closed.
2215 if (options.control_persist) {
2217 setproctitle("[stopped mux]");
2221 /* client specific fatal cleanup */
2225 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2226 leave_non_blocking();
2227 if (options.control_path != NULL && muxserver_sock != -1)
2228 unlink(options.control_path);
2229 ssh_kill_proxy_command();