1 /* $OpenBSD: clientloop.c,v 1.258 2014/02/02 03:44:31 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 = monotime() +
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((u_char)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 = monotime() + 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");
400 * If we didn't get authentication data, just make up some
401 * data. The forwarding code will check the validity of the
402 * response anyway, and substitute this data. The X11
403 * server, however, will ignore this fake data and use
404 * whatever authentication mechanisms it was using otherwise
405 * for the local connection.
410 logit("Warning: No xauth data; "
411 "using fake authentication data for X11 forwarding.");
412 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
413 for (i = 0; i < 16; i++) {
416 snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
424 * This is called when the interactive is entered. This checks if there is
425 * an EOF coming on stdin. We must check this explicitly, as select() does
426 * not appear to wake up when redirecting from /dev/null.
430 client_check_initial_eof_on_stdin(void)
436 * If standard input is to be "redirected from /dev/null", we simply
437 * mark that we have seen an EOF and send an EOF message to the
438 * server. Otherwise, we try to read a single character; it appears
439 * that for some files, such /dev/null, select() never wakes up for
440 * read for this descriptor, which means that we never get EOF. This
441 * way we will get the EOF if stdin comes from /dev/null or similar.
443 if (stdin_null_flag) {
444 /* Fake EOF on stdin. */
445 debug("Sending eof.");
447 packet_start(SSH_CMSG_EOF);
450 enter_non_blocking();
452 /* Check for immediate EOF on stdin. */
453 len = read(fileno(stdin), buf, 1);
456 * EOF. Record that we have seen it and send
459 debug("Sending eof.");
461 packet_start(SSH_CMSG_EOF);
463 } else if (len > 0) {
465 * Got data. We must store the data in the buffer,
466 * and also process it as an escape character if
469 if ((u_char) buf[0] == escape_char1)
472 buffer_append(&stdin_buffer, buf, 1);
474 leave_non_blocking();
480 * Make packets from buffered stdin data, and buffer them for sending to the
485 client_make_packets_from_stdin_data(void)
489 /* Send buffered stdin data to the server. */
490 while (buffer_len(&stdin_buffer) > 0 &&
491 packet_not_very_much_data_to_write()) {
492 len = buffer_len(&stdin_buffer);
493 /* Keep the packets at reasonable size. */
494 if (len > packet_get_maxsize())
495 len = packet_get_maxsize();
496 packet_start(SSH_CMSG_STDIN_DATA);
497 packet_put_string(buffer_ptr(&stdin_buffer), len);
499 buffer_consume(&stdin_buffer, len);
500 /* If we have a pending EOF, send it now. */
501 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
502 packet_start(SSH_CMSG_EOF);
509 * Checks if the client window has changed, and sends a packet about it to
510 * the server if so. The actual change is detected elsewhere (by a software
511 * interrupt on Unix); this just checks the flag and sends a message if
516 client_check_window_change(void)
520 if (! received_window_change_signal)
523 received_window_change_signal = 0;
525 debug2("client_check_window_change: changed");
528 channel_send_window_changes();
530 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
532 packet_start(SSH_CMSG_WINDOW_SIZE);
533 packet_put_int((u_int)ws.ws_row);
534 packet_put_int((u_int)ws.ws_col);
535 packet_put_int((u_int)ws.ws_xpixel);
536 packet_put_int((u_int)ws.ws_ypixel);
542 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
544 struct global_confirm *gc;
546 if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
549 gc->cb(type, seq, gc->ctx);
550 if (--gc->ref_count <= 0) {
551 TAILQ_REMOVE(&global_confirms, gc, entry);
552 explicit_bzero(gc, sizeof(*gc));
556 packet_set_alive_timeouts(0);
560 server_alive_check(void)
562 if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
563 logit("Timeout, server %s not responding.", host);
566 packet_start(SSH2_MSG_GLOBAL_REQUEST);
567 packet_put_cstring("keepalive@openssh.com");
568 packet_put_char(1); /* boolean: want reply */
570 /* Insert an empty placeholder to maintain ordering */
571 client_register_global_confirm(NULL, NULL);
575 * Waits until the client can do something (some data becomes available on
576 * one of the file descriptors).
579 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
580 int *maxfdp, u_int *nallocp, int rekeying)
582 struct timeval tv, *tvp;
584 time_t minwait_secs = 0, server_alive_time = 0, now = monotime();
587 /* Add any selections by the channel mechanism. */
588 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp,
589 &minwait_secs, rekeying);
592 /* Read from the connection, unless our buffers are full. */
593 if (buffer_len(&stdout_buffer) < buffer_high &&
594 buffer_len(&stderr_buffer) < buffer_high &&
595 channel_not_very_much_buffered_data())
596 FD_SET(connection_in, *readsetp);
598 * Read from stdin, unless we have seen EOF or have very much
599 * buffered data to send to the server.
601 if (!stdin_eof && packet_not_very_much_data_to_write())
602 FD_SET(fileno(stdin), *readsetp);
604 /* Select stdout/stderr if have data in buffer. */
605 if (buffer_len(&stdout_buffer) > 0)
606 FD_SET(fileno(stdout), *writesetp);
607 if (buffer_len(&stderr_buffer) > 0)
608 FD_SET(fileno(stderr), *writesetp);
610 /* channel_prepare_select could have closed the last channel */
611 if (session_closed && !channel_still_open() &&
612 !packet_have_data_to_write()) {
613 /* clear mask since we did not call select() */
614 memset(*readsetp, 0, *nallocp);
615 memset(*writesetp, 0, *nallocp);
618 FD_SET(connection_in, *readsetp);
622 /* Select server connection if have data to write to the server. */
623 if (packet_have_data_to_write())
624 FD_SET(connection_out, *writesetp);
627 * Wait for something to happen. This will suspend the process until
628 * some selected descriptor can be read, written, or has some other
629 * event pending, or a timeout expires.
632 timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
633 if (options.server_alive_interval > 0 && compat20) {
634 timeout_secs = options.server_alive_interval;
635 server_alive_time = now + options.server_alive_interval;
637 if (options.rekey_interval > 0 && compat20 && !rekeying)
638 timeout_secs = MIN(timeout_secs, packet_get_rekey_timeout());
639 set_control_persist_exit_time();
640 if (control_persist_exit_time > 0) {
641 timeout_secs = MIN(timeout_secs,
642 control_persist_exit_time - now);
643 if (timeout_secs < 0)
646 if (minwait_secs != 0)
647 timeout_secs = MIN(timeout_secs, (int)minwait_secs);
648 if (timeout_secs == INT_MAX)
651 tv.tv_sec = timeout_secs;
656 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
661 * We have to clear the select masks, because we return.
662 * We have to return, because the mainloop checks for the flags
663 * set by the signal handlers.
665 memset(*readsetp, 0, *nallocp);
666 memset(*writesetp, 0, *nallocp);
670 /* Note: we might still have data in the buffers. */
671 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
672 buffer_append(&stderr_buffer, buf, strlen(buf));
674 } else if (ret == 0) {
676 * Timeout. Could have been either keepalive or rekeying.
677 * Keepalive we check here, rekeying is checked in clientloop.
679 if (server_alive_time != 0 && server_alive_time <= monotime())
680 server_alive_check();
686 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
688 /* Flush stdout and stderr buffers. */
689 if (buffer_len(bout) > 0)
690 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
692 if (buffer_len(berr) > 0)
693 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
696 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
699 * Free (and clear) the buffer to reduce the amount of data that gets
706 /* Send the suspend signal to the program itself. */
707 kill(getpid(), SIGTSTP);
709 /* Reset window sizes in case they have changed */
710 received_window_change_signal = 1;
712 /* OK, we have been continued by the user. Reinitialize buffers. */
717 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
721 client_process_net_input(fd_set *readset)
724 char buf[SSH_IOBUFSZ];
727 * Read input from the server, and add any such data to the buffer of
728 * the packet subsystem.
730 if (FD_ISSET(connection_in, readset)) {
731 /* Read as much as possible. */
732 len = roaming_read(connection_in, buf, sizeof(buf), &cont);
733 if (len == 0 && cont == 0) {
735 * Received EOF. The remote host has closed the
738 snprintf(buf, sizeof buf,
739 "Connection to %.300s closed by remote host.\r\n",
741 buffer_append(&stderr_buffer, buf, strlen(buf));
746 * There is a kernel bug on Solaris that causes select to
747 * sometimes wake up even though there is no data available.
750 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
755 * An error has encountered. Perhaps there is a
758 snprintf(buf, sizeof buf,
759 "Read from remote host %.300s: %.100s\r\n",
760 host, strerror(errno));
761 buffer_append(&stderr_buffer, buf, strlen(buf));
765 packet_process_incoming(buf, len);
770 client_status_confirm(int type, Channel *c, void *ctx)
772 struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
777 * If a TTY was explicitly requested, then a failure to allocate
780 if (cr->action == CONFIRM_TTY &&
781 (options.request_tty == REQUEST_TTY_FORCE ||
782 options.request_tty == REQUEST_TTY_YES))
783 cr->action = CONFIRM_CLOSE;
785 /* XXX supress on mux _client_ quietmode */
786 tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
787 c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
789 if (type == SSH2_MSG_CHANNEL_SUCCESS) {
790 debug2("%s request accepted on channel %d",
791 cr->request_type, c->self);
792 } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
794 snprintf(errmsg, sizeof(errmsg),
795 "%s request failed\r\n", cr->request_type);
797 snprintf(errmsg, sizeof(errmsg),
798 "%s request failed on channel %d",
799 cr->request_type, c->self);
801 /* If error occurred on primary session channel, then exit */
802 if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
805 * If error occurred on mux client, append to
809 buffer_append(&c->extended, errmsg,
813 if (cr->action == CONFIRM_TTY) {
815 * If a TTY allocation error occurred, then arrange
816 * for the correct TTY to leave raw mode.
818 if (c->self == session_ident)
821 mux_tty_alloc_failed(c);
822 } else if (cr->action == CONFIRM_CLOSE) {
824 chan_write_failed(c);
831 client_abandon_status_confirm(Channel *c, void *ctx)
837 client_expect_confirm(int id, const char *request,
838 enum confirm_action action)
840 struct channel_reply_ctx *cr = xcalloc(1, sizeof(*cr));
842 cr->request_type = request;
845 channel_register_status_confirm(id, client_status_confirm,
846 client_abandon_status_confirm, cr);
850 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
852 struct global_confirm *gc, *last_gc;
854 /* Coalesce identical callbacks */
855 last_gc = TAILQ_LAST(&global_confirms, global_confirms);
856 if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
857 if (++last_gc->ref_count >= INT_MAX)
858 fatal("%s: last_gc->ref_count = %d",
859 __func__, last_gc->ref_count);
863 gc = xcalloc(1, sizeof(*gc));
867 TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
871 process_cmdline(void)
873 void (*handler)(int);
874 char *s, *cmd, *cancel_host;
875 int delete = 0, local = 0, remote = 0, dynamic = 0;
879 memset(&fwd, 0, sizeof(fwd));
880 fwd.listen_host = fwd.connect_host = NULL;
882 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
883 handler = signal(SIGINT, SIG_IGN);
884 cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
887 while (isspace((u_char)*s))
890 s++; /* Skip cmdline '-', if any */
894 if (*s == 'h' || *s == 'H' || *s == '?') {
896 logit(" -L[bind_address:]port:host:hostport "
897 "Request local forward");
898 logit(" -R[bind_address:]port:host:hostport "
899 "Request remote forward");
900 logit(" -D[bind_address:]port "
901 "Request dynamic forward");
902 logit(" -KL[bind_address:]port "
903 "Cancel local forward");
904 logit(" -KR[bind_address:]port "
905 "Cancel remote forward");
906 logit(" -KD[bind_address:]port "
907 "Cancel dynamic forward");
908 if (!options.permit_local_command)
911 "Execute local command");
915 if (*s == '!' && options.permit_local_command) {
932 logit("Invalid command.");
936 if (delete && !compat20) {
937 logit("Not supported for SSH protocol version 1.");
941 while (isspace((u_char)*++s))
944 /* XXX update list of forwards in options */
947 cancel_host = hpdelim(&s); /* may be NULL */
949 cancel_port = a2port(s);
950 cancel_host = cleanhostname(cancel_host);
952 cancel_port = a2port(cancel_host);
955 if (cancel_port <= 0) {
956 logit("Bad forwarding close port");
960 ok = channel_request_rforward_cancel(cancel_host,
963 ok = channel_cancel_lport_listener(cancel_host,
964 cancel_port, 0, options.gateway_ports) > 0;
966 ok = channel_cancel_lport_listener(cancel_host,
967 cancel_port, CHANNEL_CANCEL_PORT_STATIC,
968 options.gateway_ports) > 0;
970 logit("Unkown port forwarding.");
973 logit("Canceled forwarding.");
975 if (!parse_forward(&fwd, s, dynamic, remote)) {
976 logit("Bad forwarding specification.");
979 if (local || dynamic) {
980 if (!channel_setup_local_fwd_listener(fwd.listen_host,
981 fwd.listen_port, fwd.connect_host,
982 fwd.connect_port, options.gateway_ports)) {
983 logit("Port forwarding failed.");
987 if (channel_request_remote_forwarding(fwd.listen_host,
988 fwd.listen_port, fwd.connect_host,
989 fwd.connect_port) < 0) {
990 logit("Port forwarding failed.");
994 logit("Forwarding port.");
998 signal(SIGINT, handler);
999 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1001 free(fwd.listen_host);
1002 free(fwd.connect_host);
1005 /* reasons to suppress output of an escape command in help output */
1006 #define SUPPRESS_NEVER 0 /* never suppress, always show */
1007 #define SUPPRESS_PROTO1 1 /* don't show in protocol 1 sessions */
1008 #define SUPPRESS_MUXCLIENT 2 /* don't show in mux client sessions */
1009 #define SUPPRESS_MUXMASTER 4 /* don't show in mux master sessions */
1010 #define SUPPRESS_SYSLOG 8 /* don't show when logging to syslog */
1011 struct escape_help_text {
1016 static struct escape_help_text esc_txt[] = {
1017 {".", "terminate session", SUPPRESS_MUXMASTER},
1018 {".", "terminate connection (and any multiplexed sessions)",
1019 SUPPRESS_MUXCLIENT},
1020 {"B", "send a BREAK to the remote system", SUPPRESS_PROTO1},
1021 {"C", "open a command line", SUPPRESS_MUXCLIENT},
1022 {"R", "request rekey", SUPPRESS_PROTO1},
1023 {"V/v", "decrease/increase verbosity (LogLevel)", SUPPRESS_MUXCLIENT},
1024 {"^Z", "suspend ssh", SUPPRESS_MUXCLIENT},
1025 {"#", "list forwarded connections", SUPPRESS_NEVER},
1026 {"&", "background ssh (when waiting for connections to terminate)",
1027 SUPPRESS_MUXCLIENT},
1028 {"?", "this message", SUPPRESS_NEVER},
1032 print_escape_help(Buffer *b, int escape_char, int protocol2, int mux_client,
1035 unsigned int i, suppress_flags;
1038 snprintf(string, sizeof string, "%c?\r\n"
1039 "Supported escape sequences:\r\n", escape_char);
1040 buffer_append(b, string, strlen(string));
1042 suppress_flags = (protocol2 ? 0 : SUPPRESS_PROTO1) |
1043 (mux_client ? SUPPRESS_MUXCLIENT : 0) |
1044 (mux_client ? 0 : SUPPRESS_MUXMASTER) |
1045 (using_stderr ? 0 : SUPPRESS_SYSLOG);
1047 for (i = 0; i < sizeof(esc_txt)/sizeof(esc_txt[0]); i++) {
1048 if (esc_txt[i].flags & suppress_flags)
1050 snprintf(string, sizeof string, " %c%-3s - %s\r\n",
1051 escape_char, esc_txt[i].cmd, esc_txt[i].text);
1052 buffer_append(b, string, strlen(string));
1055 snprintf(string, sizeof string,
1056 " %c%c - send the escape character by typing it twice\r\n"
1057 "(Note that escapes are only recognized immediately after "
1058 "newline.)\r\n", escape_char, escape_char);
1059 buffer_append(b, string, strlen(string));
1063 * Process the characters one by one, call with c==NULL for proto1 case.
1066 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
1075 int *escape_pendingp, escape_char;
1076 struct escape_filter_ctx *efc;
1079 escape_pendingp = &escape_pending1;
1080 escape_char = escape_char1;
1082 if (c->filter_ctx == NULL)
1084 efc = (struct escape_filter_ctx *)c->filter_ctx;
1085 escape_pendingp = &efc->escape_pending;
1086 escape_char = efc->escape_char;
1092 for (i = 0; i < (u_int)len; i++) {
1093 /* Get one character at a time. */
1096 if (*escape_pendingp) {
1097 /* We have previously seen an escape character. */
1098 /* Clear the flag now. */
1099 *escape_pendingp = 0;
1101 /* Process the escaped character. */
1104 /* Terminate the connection. */
1105 snprintf(string, sizeof string, "%c.\r\n",
1107 buffer_append(berr, string, strlen(string));
1109 if (c && c->ctl_chan != -1) {
1110 chan_read_failed(c);
1111 chan_write_failed(c);
1113 c->detach_user(c->self, NULL);
1114 c->type = SSH_CHANNEL_ABANDONED;
1115 buffer_clear(&c->input);
1123 /* XXX support this for mux clients */
1124 if (c && c->ctl_chan != -1) {
1128 snprintf(b, sizeof b, "^Z");
1130 snprintf(b, sizeof b, "%c", ch);
1131 snprintf(string, sizeof string,
1132 "%c%s escape not available to "
1133 "multiplexed sessions\r\n",
1135 buffer_append(berr, string,
1139 /* Suspend the program. Inform the user */
1140 snprintf(string, sizeof string,
1141 "%c^Z [suspend ssh]\r\n", escape_char);
1142 buffer_append(berr, string, strlen(string));
1144 /* Restore terminal modes and suspend. */
1145 client_suspend_self(bin, bout, berr);
1147 /* We have been continued. */
1152 snprintf(string, sizeof string,
1153 "%cB\r\n", escape_char);
1154 buffer_append(berr, string,
1156 channel_request_start(c->self,
1158 packet_put_int(1000);
1165 if (datafellows & SSH_BUG_NOREKEY)
1166 logit("Server does not "
1167 "support re-keying");
1176 if (c && c->ctl_chan != -1)
1178 if (!log_is_on_stderr()) {
1179 snprintf(string, sizeof string,
1180 "%c%c [Logging to syslog]\r\n",
1182 buffer_append(berr, string,
1186 if (ch == 'V' && options.log_level >
1188 log_change_level(--options.log_level);
1189 if (ch == 'v' && options.log_level <
1190 SYSLOG_LEVEL_DEBUG3)
1191 log_change_level(++options.log_level);
1192 snprintf(string, sizeof string,
1193 "%c%c [LogLevel %s]\r\n", escape_char, ch,
1194 log_level_name(options.log_level));
1195 buffer_append(berr, string, strlen(string));
1199 if (c && c->ctl_chan != -1)
1202 * Detach the program (continue to serve
1203 * connections, but put in background and no
1204 * more new connections).
1206 /* Restore tty modes. */
1208 options.request_tty == REQUEST_TTY_FORCE);
1210 /* Stop listening for new connections. */
1211 channel_stop_listening();
1213 snprintf(string, sizeof string,
1214 "%c& [backgrounded]\n", escape_char);
1215 buffer_append(berr, string, strlen(string));
1217 /* Fork into background. */
1220 error("fork: %.100s", strerror(errno));
1223 if (pid != 0) { /* This is the parent. */
1224 /* The parent just exits. */
1227 /* The child continues serving connections. */
1229 buffer_append(bin, "\004", 1);
1230 /* fake EOF on stdin */
1232 } else if (!stdin_eof) {
1234 * Sending SSH_CMSG_EOF alone does not
1235 * always appear to be enough. So we
1236 * try to send an EOF character first.
1238 packet_start(SSH_CMSG_STDIN_DATA);
1239 packet_put_string("\004", 1);
1243 if (buffer_len(bin) == 0) {
1244 packet_start(SSH_CMSG_EOF);
1251 print_escape_help(berr, escape_char, compat20,
1252 (c && c->ctl_chan != -1),
1253 log_is_on_stderr());
1257 snprintf(string, sizeof string, "%c#\r\n",
1259 buffer_append(berr, string, strlen(string));
1260 s = channel_open_message();
1261 buffer_append(berr, s, strlen(s));
1266 if (c && c->ctl_chan != -1)
1272 if (ch != escape_char) {
1273 buffer_put_char(bin, escape_char);
1276 /* Escaped characters fall through here */
1281 * The previous character was not an escape char.
1282 * Check if this is an escape.
1284 if (last_was_cr && ch == escape_char) {
1286 * It is. Set the flag and continue to
1289 *escape_pendingp = 1;
1295 * Normal character. Record whether it was a newline,
1296 * and append it to the buffer.
1298 last_was_cr = (ch == '\r' || ch == '\n');
1299 buffer_put_char(bin, ch);
1306 client_process_input(fd_set *readset)
1309 char buf[SSH_IOBUFSZ];
1311 /* Read input from stdin. */
1312 if (FD_ISSET(fileno(stdin), readset)) {
1313 /* Read as much as possible. */
1314 len = read(fileno(stdin), buf, sizeof(buf));
1316 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1317 return; /* we'll try again later */
1320 * Received EOF or error. They are treated
1321 * similarly, except that an error message is printed
1322 * if it was an error condition.
1325 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1327 buffer_append(&stderr_buffer, buf, strlen(buf));
1329 /* Mark that we have seen EOF. */
1332 * Send an EOF message to the server unless there is
1333 * data in the buffer. If there is data in the
1334 * buffer, no message will be sent now. Code
1335 * elsewhere will send the EOF when the buffer
1336 * becomes empty if stdin_eof is set.
1338 if (buffer_len(&stdin_buffer) == 0) {
1339 packet_start(SSH_CMSG_EOF);
1342 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1344 * Normal successful read, and no escape character.
1345 * Just append the data to buffer.
1347 buffer_append(&stdin_buffer, buf, len);
1350 * Normal, successful read. But we have an escape
1351 * character and have to process the characters one
1354 if (process_escapes(NULL, &stdin_buffer,
1355 &stdout_buffer, &stderr_buffer, buf, len) == -1)
1362 client_process_output(fd_set *writeset)
1367 /* Write buffered output to stdout. */
1368 if (FD_ISSET(fileno(stdout), writeset)) {
1369 /* Write as much data as possible. */
1370 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1371 buffer_len(&stdout_buffer));
1373 if (errno == EINTR || errno == EAGAIN ||
1374 errno == EWOULDBLOCK)
1378 * An error or EOF was encountered. Put an
1379 * error message to stderr buffer.
1381 snprintf(buf, sizeof buf,
1382 "write stdout: %.50s\r\n", strerror(errno));
1383 buffer_append(&stderr_buffer, buf, strlen(buf));
1388 /* Consume printed data from the buffer. */
1389 buffer_consume(&stdout_buffer, len);
1391 /* Write buffered output to stderr. */
1392 if (FD_ISSET(fileno(stderr), writeset)) {
1393 /* Write as much data as possible. */
1394 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1395 buffer_len(&stderr_buffer));
1397 if (errno == EINTR || errno == EAGAIN ||
1398 errno == EWOULDBLOCK)
1402 * EOF or error, but can't even print
1409 /* Consume printed characters from the buffer. */
1410 buffer_consume(&stderr_buffer, len);
1415 * Get packets from the connection input buffer, and process them as long as
1416 * there are packets available.
1418 * Any unknown packets received during the actual
1419 * session cause the session to terminate. This is
1420 * intended to make debugging easier since no
1421 * confirmations are sent. Any compatible protocol
1422 * extensions must be negotiated during the
1423 * preparatory phase.
1427 client_process_buffered_input_packets(void)
1429 dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1430 compat20 ? xxx_kex : NULL);
1433 /* scan buf[] for '~' before sending data to the peer */
1435 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1437 client_new_escape_filter_ctx(int escape_char)
1439 struct escape_filter_ctx *ret;
1441 ret = xcalloc(1, sizeof(*ret));
1442 ret->escape_pending = 0;
1443 ret->escape_char = escape_char;
1447 /* Free the escape filter context on channel free */
1449 client_filter_cleanup(int cid, void *ctx)
1455 client_simple_escape_filter(Channel *c, char *buf, int len)
1457 if (c->extended_usage != CHAN_EXTENDED_WRITE)
1460 return process_escapes(c, &c->input, &c->output, &c->extended,
1465 client_channel_closed(int id, void *arg)
1467 channel_cancel_cleanup(id);
1469 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1473 * Implements the interactive session with the server. This is called after
1474 * the user has been authenticated, and a command has been started on the
1475 * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1476 * used as an escape character for terminating or suspending the session.
1480 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1482 fd_set *readset = NULL, *writeset = NULL;
1483 double start_time, total_time;
1484 int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1485 u_int64_t ibytes, obytes;
1489 debug("Entering interactive session.");
1491 start_time = get_current_time();
1493 /* Initialize variables. */
1494 escape_pending1 = 0;
1498 buffer_high = 64 * 1024;
1499 connection_in = packet_get_connection_in();
1500 connection_out = packet_get_connection_out();
1501 max_fd = MAX(connection_in, connection_out);
1504 /* enable nonblocking unless tty */
1505 if (!isatty(fileno(stdin)))
1506 set_nonblock(fileno(stdin));
1507 if (!isatty(fileno(stdout)))
1508 set_nonblock(fileno(stdout));
1509 if (!isatty(fileno(stderr)))
1510 set_nonblock(fileno(stderr));
1511 max_fd = MAX(max_fd, fileno(stdin));
1512 max_fd = MAX(max_fd, fileno(stdout));
1513 max_fd = MAX(max_fd, fileno(stderr));
1516 escape_char1 = escape_char_arg;
1518 /* Initialize buffers. */
1519 buffer_init(&stdin_buffer);
1520 buffer_init(&stdout_buffer);
1521 buffer_init(&stderr_buffer);
1523 client_init_dispatch();
1526 * Set signal handlers, (e.g. to restore non-blocking mode)
1527 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1529 if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1530 signal(SIGHUP, signal_handler);
1531 if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1532 signal(SIGINT, signal_handler);
1533 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1534 signal(SIGQUIT, signal_handler);
1535 if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1536 signal(SIGTERM, signal_handler);
1537 signal(SIGWINCH, window_change_handler);
1540 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1543 session_ident = ssh2_chan_id;
1544 if (session_ident != -1) {
1545 if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1546 channel_register_filter(session_ident,
1547 client_simple_escape_filter, NULL,
1548 client_filter_cleanup,
1549 client_new_escape_filter_ctx(
1552 channel_register_cleanup(session_ident,
1553 client_channel_closed, 0);
1556 /* Check if we should immediately send eof on stdin. */
1557 client_check_initial_eof_on_stdin();
1560 /* Main loop of the client for the interactive session mode. */
1561 while (!quit_pending) {
1563 /* Process buffered packets sent by the server. */
1564 client_process_buffered_input_packets();
1566 if (compat20 && session_closed && !channel_still_open())
1569 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1572 debug("rekeying in progress");
1575 * Make packets of buffered stdin data, and buffer
1576 * them for sending to the server.
1579 client_make_packets_from_stdin_data();
1582 * Make packets from buffered channel data, and
1583 * enqueue them for sending to the server.
1585 if (packet_not_very_much_data_to_write())
1586 channel_output_poll();
1589 * Check if the window size has changed, and buffer a
1590 * message about it to the server if so.
1592 client_check_window_change();
1598 * Wait until we have something to do (something becomes
1599 * available on one of the descriptors).
1602 client_wait_until_can_do_something(&readset, &writeset,
1603 &max_fd2, &nalloc, rekeying);
1608 /* Do channel operations unless rekeying in progress. */
1610 channel_after_select(readset, writeset);
1611 if (need_rekeying || packet_need_rekeying()) {
1612 debug("need rekeying");
1614 kex_send_kexinit(xxx_kex);
1619 /* Buffer input from the connection. */
1620 client_process_net_input(readset);
1626 /* Buffer data from stdin */
1627 client_process_input(readset);
1629 * Process output to stdout and stderr. Output to
1630 * the connection is processed elsewhere (above).
1632 client_process_output(writeset);
1635 if (session_resumed) {
1636 connection_in = packet_get_connection_in();
1637 connection_out = packet_get_connection_out();
1638 max_fd = MAX(max_fd, connection_out);
1639 max_fd = MAX(max_fd, connection_in);
1640 session_resumed = 0;
1644 * Send as much buffered packet data as possible to the
1647 if (FD_ISSET(connection_out, writeset))
1648 packet_write_poll();
1651 * If we are a backgrounded control master, and the
1652 * timeout has expired without any active client
1653 * connections, then quit.
1655 if (control_persist_exit_time > 0) {
1656 if (monotime() >= control_persist_exit_time) {
1657 debug("ControlPersist timeout expired");
1665 /* Terminate the session. */
1667 /* Stop watching for window change. */
1668 signal(SIGWINCH, SIG_DFL);
1671 packet_start(SSH2_MSG_DISCONNECT);
1672 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1673 packet_put_cstring("disconnected by user");
1674 packet_put_cstring(""); /* language tag */
1676 packet_write_wait();
1682 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1684 /* restore blocking io */
1685 if (!isatty(fileno(stdin)))
1686 unset_nonblock(fileno(stdin));
1687 if (!isatty(fileno(stdout)))
1688 unset_nonblock(fileno(stdout));
1689 if (!isatty(fileno(stderr)))
1690 unset_nonblock(fileno(stderr));
1693 * If there was no shell or command requested, there will be no remote
1694 * exit status to be returned. In that case, clear error code if the
1695 * connection was deliberately terminated at this end.
1697 if (no_shell_flag && received_signal == SIGTERM) {
1698 received_signal = 0;
1702 if (received_signal)
1703 fatal("Killed by signal %d.", (int) received_signal);
1706 * In interactive mode (with pseudo tty) display a message indicating
1707 * that the connection has been closed.
1709 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1710 snprintf(buf, sizeof buf,
1711 "Connection to %.64s closed.\r\n", host);
1712 buffer_append(&stderr_buffer, buf, strlen(buf));
1715 /* Output any buffered data for stdout. */
1716 if (buffer_len(&stdout_buffer) > 0) {
1717 len = atomicio(vwrite, fileno(stdout),
1718 buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1719 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1720 error("Write failed flushing stdout buffer.");
1722 buffer_consume(&stdout_buffer, len);
1725 /* Output any buffered data for stderr. */
1726 if (buffer_len(&stderr_buffer) > 0) {
1727 len = atomicio(vwrite, fileno(stderr),
1728 buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1729 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1730 error("Write failed flushing stderr buffer.");
1732 buffer_consume(&stderr_buffer, len);
1735 /* Clear and free any buffers. */
1736 memset(buf, 0, sizeof(buf));
1737 buffer_free(&stdin_buffer);
1738 buffer_free(&stdout_buffer);
1739 buffer_free(&stderr_buffer);
1741 /* Report bytes transferred, and transfer rates. */
1742 total_time = get_current_time() - start_time;
1743 packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1744 packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1745 verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1746 (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1748 verbose("Bytes per second: sent %.1f, received %.1f",
1749 obytes / total_time, ibytes / total_time);
1750 /* Return the exit status of the program. */
1751 debug("Exit status %d", exit_status);
1758 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1761 char *data = packet_get_string(&data_len);
1763 buffer_append(&stdout_buffer, data, data_len);
1764 explicit_bzero(data, data_len);
1768 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1771 char *data = packet_get_string(&data_len);
1773 buffer_append(&stderr_buffer, data, data_len);
1774 explicit_bzero(data, data_len);
1778 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1780 exit_status = packet_get_int();
1782 /* Acknowledge the exit. */
1783 packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1786 * Must wait for packet to be sent since we are
1789 packet_write_wait();
1790 /* Flag that we want to exit. */
1794 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1797 int remote_id, sock;
1799 /* Read the remote channel number from the message. */
1800 remote_id = packet_get_int();
1804 * Get a connection to the local authentication agent (this may again
1807 sock = ssh_get_authentication_socket();
1810 * If we could not connect the agent, send an error message back to
1811 * the server. This should never happen unless the agent dies,
1812 * because authentication forwarding is only enabled if we have an
1816 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1817 -1, 0, 0, 0, "authentication agent connection", 1);
1818 c->remote_id = remote_id;
1822 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1823 packet_put_int(remote_id);
1825 /* Send a confirmation to the remote host. */
1826 debug("Forwarding authentication connection.");
1827 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1828 packet_put_int(remote_id);
1829 packet_put_int(c->self);
1835 client_request_forwarded_tcpip(const char *request_type, int rchan)
1838 char *listen_address, *originator_address;
1839 u_short listen_port, originator_port;
1841 /* Get rest of the packet */
1842 listen_address = packet_get_string(NULL);
1843 listen_port = packet_get_int();
1844 originator_address = packet_get_string(NULL);
1845 originator_port = packet_get_int();
1848 debug("client_request_forwarded_tcpip: listen %s port %d, "
1849 "originator %s port %d", listen_address, listen_port,
1850 originator_address, originator_port);
1852 c = channel_connect_by_listen_address(listen_port,
1853 "forwarded-tcpip", originator_address);
1855 free(originator_address);
1856 free(listen_address);
1861 client_request_x11(const char *request_type, int rchan)
1865 u_short originator_port;
1868 if (!options.forward_x11) {
1869 error("Warning: ssh server tried X11 forwarding.");
1870 error("Warning: this is probably a break-in attempt by a "
1871 "malicious server.");
1874 if (x11_refuse_time != 0 && monotime() >= x11_refuse_time) {
1875 verbose("Rejected X11 connection after ForwardX11Timeout "
1879 originator = packet_get_string(NULL);
1880 if (datafellows & SSH_BUG_X11FWD) {
1881 debug2("buggy server: x11 request w/o originator_port");
1882 originator_port = 0;
1884 originator_port = packet_get_int();
1887 /* XXX check permission */
1888 debug("client_request_x11: request from %s %d", originator,
1891 sock = x11_connect_display();
1894 c = channel_new("x11",
1895 SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1896 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0, "x11", 1);
1902 client_request_agent(const char *request_type, int rchan)
1907 if (!options.forward_agent) {
1908 error("Warning: ssh server tried agent forwarding.");
1909 error("Warning: this is probably a break-in attempt by a "
1910 "malicious server.");
1913 sock = ssh_get_authentication_socket();
1916 c = channel_new("authentication agent connection",
1917 SSH_CHANNEL_OPEN, sock, sock, -1,
1918 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0,
1919 "authentication agent connection", 1);
1925 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1930 if (tun_mode == SSH_TUNMODE_NO)
1934 error("Tunnel forwarding is not supported for protocol 1");
1938 debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1940 /* Open local tunnel device */
1941 if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1942 error("Tunnel device open failed.");
1946 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1947 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT, 0, "tun", 1);
1950 #if defined(SSH_TUN_FILTER)
1951 if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1952 channel_register_filter(c->self, sys_tun_infilter,
1953 sys_tun_outfilter, NULL, NULL);
1956 packet_start(SSH2_MSG_CHANNEL_OPEN);
1957 packet_put_cstring("tun@openssh.com");
1958 packet_put_int(c->self);
1959 packet_put_int(c->local_window_max);
1960 packet_put_int(c->local_maxpacket);
1961 packet_put_int(tun_mode);
1962 packet_put_int(remote_tun);
1968 /* XXXX move to generic input handler */
1970 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1975 u_int rmaxpack, rwindow, len;
1977 ctype = packet_get_string(&len);
1978 rchan = packet_get_int();
1979 rwindow = packet_get_int();
1980 rmaxpack = packet_get_int();
1982 debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1983 ctype, rchan, rwindow, rmaxpack);
1985 if (strcmp(ctype, "forwarded-tcpip") == 0) {
1986 c = client_request_forwarded_tcpip(ctype, rchan);
1987 } else if (strcmp(ctype, "x11") == 0) {
1988 c = client_request_x11(ctype, rchan);
1989 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1990 c = client_request_agent(ctype, rchan);
1992 /* XXX duplicate : */
1994 debug("confirm %s", ctype);
1995 c->remote_id = rchan;
1996 c->remote_window = rwindow;
1997 c->remote_maxpacket = rmaxpack;
1998 if (c->type != SSH_CHANNEL_CONNECTING) {
1999 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
2000 packet_put_int(c->remote_id);
2001 packet_put_int(c->self);
2002 packet_put_int(c->local_window);
2003 packet_put_int(c->local_maxpacket);
2007 debug("failure %s", ctype);
2008 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
2009 packet_put_int(rchan);
2010 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
2011 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
2012 packet_put_cstring("open failed");
2013 packet_put_cstring("");
2020 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
2023 int exitval, id, reply, success = 0;
2026 id = packet_get_int();
2027 rtype = packet_get_string(NULL);
2028 reply = packet_get_char();
2030 debug("client_input_channel_req: channel %d rtype %s reply %d",
2034 error("client_input_channel_req: request for channel -1");
2035 } else if ((c = channel_lookup(id)) == NULL) {
2036 error("client_input_channel_req: channel %d: "
2037 "unknown channel", id);
2038 } else if (strcmp(rtype, "eow@openssh.com") == 0) {
2041 } else if (strcmp(rtype, "exit-status") == 0) {
2042 exitval = packet_get_int();
2043 if (c->ctl_chan != -1) {
2044 mux_exit_message(c, exitval);
2046 } else if (id == session_ident) {
2047 /* Record exit value of local session */
2049 exit_status = exitval;
2051 /* Probably for a mux channel that has already closed */
2052 debug("%s: no sink for exit-status on channel %d",
2057 if (reply && c != NULL) {
2058 packet_start(success ?
2059 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
2060 packet_put_int(c->remote_id);
2066 client_input_global_request(int type, u_int32_t seq, void *ctxt)
2072 rtype = packet_get_string(NULL);
2073 want_reply = packet_get_char();
2074 debug("client_input_global_request: rtype %s want_reply %d",
2077 packet_start(success ?
2078 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2080 packet_write_wait();
2086 client_session2_setup(int id, int want_tty, int want_subsystem,
2087 const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2092 debug2("%s: id %d", __func__, id);
2094 if ((c = channel_lookup(id)) == NULL)
2095 fatal("client_session2_setup: channel %d: unknown channel", id);
2097 packet_set_interactive(want_tty,
2098 options.ip_qos_interactive, options.ip_qos_bulk);
2103 /* Store window size in the packet. */
2104 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2105 memset(&ws, 0, sizeof(ws));
2107 channel_request_start(id, "pty-req", 1);
2108 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2109 packet_put_cstring(term != NULL ? term : "");
2110 packet_put_int((u_int)ws.ws_col);
2111 packet_put_int((u_int)ws.ws_row);
2112 packet_put_int((u_int)ws.ws_xpixel);
2113 packet_put_int((u_int)ws.ws_ypixel);
2115 tiop = get_saved_tio();
2116 tty_make_modes(-1, tiop);
2118 /* XXX wait for reply */
2122 /* Transfer any environment variables from client to server */
2123 if (options.num_send_env != 0 && env != NULL) {
2127 debug("Sending environment.");
2128 for (i = 0; env[i] != NULL; i++) {
2130 name = xstrdup(env[i]);
2131 if ((val = strchr(name, '=')) == NULL) {
2138 for (j = 0; j < options.num_send_env; j++) {
2139 if (match_pattern(name, options.send_env[j])) {
2145 debug3("Ignored env %s", name);
2150 debug("Sending env %s = %s", name, val);
2151 channel_request_start(id, "env", 0);
2152 packet_put_cstring(name);
2153 packet_put_cstring(val);
2159 len = buffer_len(cmd);
2163 if (want_subsystem) {
2164 debug("Sending subsystem: %.*s",
2165 len, (u_char*)buffer_ptr(cmd));
2166 channel_request_start(id, "subsystem", 1);
2167 client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2169 debug("Sending command: %.*s",
2170 len, (u_char*)buffer_ptr(cmd));
2171 channel_request_start(id, "exec", 1);
2172 client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2174 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2177 channel_request_start(id, "shell", 1);
2178 client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2184 client_init_dispatch_20(void)
2186 dispatch_init(&dispatch_protocol_error);
2188 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2189 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2190 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2191 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2192 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2193 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2194 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2195 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2196 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2197 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2198 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2199 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2202 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2204 /* global request reply messages */
2205 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2206 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2210 client_init_dispatch_13(void)
2212 dispatch_init(NULL);
2213 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2214 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2215 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2216 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2217 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2218 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2219 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2220 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2221 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2223 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2224 &client_input_agent_open : &deny_input_open);
2225 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2226 &x11_input_open : &deny_input_open);
2230 client_init_dispatch_15(void)
2232 client_init_dispatch_13();
2233 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2234 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2238 client_init_dispatch(void)
2241 client_init_dispatch_20();
2243 client_init_dispatch_13();
2245 client_init_dispatch_15();
2249 client_stop_mux(void)
2251 if (options.control_path != NULL && muxserver_sock != -1)
2252 unlink(options.control_path);
2254 * If we are in persist mode, or don't have a shell, signal that we
2255 * should close when all active channels are closed.
2257 if (options.control_persist || no_shell_flag) {
2259 setproctitle("[stopped mux]");
2263 /* client specific fatal cleanup */
2267 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2268 leave_non_blocking();
2269 if (options.control_path != NULL && muxserver_sock != -1)
2270 unlink(options.control_path);
2271 ssh_kill_proxy_command();