1 /* $OpenBSD: clientloop.c,v 1.258 2014/02/02 03:44:31 djm Exp $ */
4 * Author: Tatu Ylonen <ylo@cs.hut.fi>
5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
7 * The main loop for the interactive session (client side).
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
16 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 * 2. Redistributions in binary form must reproduce the above copyright
24 * notice, this list of conditions and the following disclaimer in the
25 * documentation and/or other materials provided with the distribution.
27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
28 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
29 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
30 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
31 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
32 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
36 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
39 * SSH2 support added by Markus Friedl.
40 * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
42 * Redistribution and use in source and binary forms, with or without
43 * modification, are permitted provided that the following conditions
45 * 1. Redistributions of source code must retain the above copyright
46 * notice, this list of conditions and the following disclaimer.
47 * 2. Redistributions in binary form must reproduce the above copyright
48 * notice, this list of conditions and the following disclaimer in the
49 * documentation and/or other materials provided with the distribution.
51 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
52 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
53 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
54 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
55 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
56 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
57 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
58 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
60 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
66 #include <sys/types.h>
67 #include <sys/ioctl.h>
68 #include <sys/param.h>
69 #ifdef HAVE_SYS_STAT_H
70 # include <sys/stat.h>
72 #ifdef HAVE_SYS_TIME_H
73 # include <sys/time.h>
75 #include <sys/socket.h>
91 #include "openbsd-compat/sys-queue.h"
100 #include "dispatch.h"
105 #include "readconf.h"
106 #include "clientloop.h"
107 #include "sshconnect.h"
109 #include "atomicio.h"
117 extern Options options;
119 /* Flag indicating that stdin should be redirected from /dev/null. */
120 extern int stdin_null_flag;
122 /* Flag indicating that no shell has been requested */
123 extern int no_shell_flag;
126 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
129 * Name of the host we are connecting to. This is the name given on the
130 * command line, or the HostName specified for the user-supplied name in a
131 * configuration file.
136 * Flag to indicate that we have received a window change signal which has
137 * not yet been processed. This will cause a message indicating the new
138 * window size to be sent to the server a little later. This is volatile
139 * because this is updated in a signal handler.
141 static volatile sig_atomic_t received_window_change_signal = 0;
142 static volatile sig_atomic_t received_signal = 0;
144 /* Flag indicating whether the user's terminal is in non-blocking mode. */
145 static int in_non_blocking_mode = 0;
147 /* Time when backgrounded control master using ControlPersist should exit */
148 static time_t control_persist_exit_time = 0;
150 /* Common data for the client loop code. */
151 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
152 static int escape_char1; /* Escape character. (proto1 only) */
153 static int escape_pending1; /* Last character was an escape (proto1 only) */
154 static int last_was_cr; /* Last character was a newline. */
155 static int exit_status; /* Used to store the command exit status. */
156 static int stdin_eof; /* EOF has been encountered on stderr. */
157 static Buffer stdin_buffer; /* Buffer for stdin data. */
158 static Buffer stdout_buffer; /* Buffer for stdout data. */
159 static Buffer stderr_buffer; /* Buffer for stderr data. */
160 static u_int buffer_high; /* Soft max buffer size. */
161 static int connection_in; /* Connection to server (input). */
162 static int connection_out; /* Connection to server (output). */
163 static int need_rekeying; /* Set to non-zero if rekeying is requested. */
164 static int session_closed; /* In SSH2: login session closed. */
165 static int x11_refuse_time; /* If >0, refuse x11 opens after this time. */
167 static void client_init_dispatch(void);
168 int session_ident = -1;
170 int session_resumed = 0;
172 /* Track escape per proto2 channel */
173 struct escape_filter_ctx {
178 /* Context for channel confirmation replies */
179 struct channel_reply_ctx {
180 const char *request_type;
182 enum confirm_action action;
185 /* Global request success/failure callbacks */
186 struct global_confirm {
187 TAILQ_ENTRY(global_confirm) entry;
188 global_confirm_cb *cb;
192 TAILQ_HEAD(global_confirms, global_confirm);
193 static struct global_confirms global_confirms =
194 TAILQ_HEAD_INITIALIZER(global_confirms);
199 void ssh_process_session2_setup(int, int, int, Buffer *);
201 /* Restores stdin to blocking mode. */
204 leave_non_blocking(void)
206 if (in_non_blocking_mode) {
207 unset_nonblock(fileno(stdin));
208 in_non_blocking_mode = 0;
212 /* Puts stdin terminal in non-blocking mode. */
215 enter_non_blocking(void)
217 in_non_blocking_mode = 1;
218 set_nonblock(fileno(stdin));
222 * Signal handler for the window change signal (SIGWINCH). This just sets a
223 * flag indicating that the window has changed.
227 window_change_handler(int sig)
229 received_window_change_signal = 1;
230 signal(SIGWINCH, window_change_handler);
234 * Signal handler for signals that cause the program to terminate. These
235 * signals must be trapped to restore terminal modes.
239 signal_handler(int sig)
241 received_signal = sig;
246 * Returns current time in seconds from Jan 1, 1970 with the maximum
247 * available resolution.
251 get_current_time(void)
254 gettimeofday(&tv, NULL);
255 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
259 * Sets control_persist_exit_time to the absolute time when the
260 * backgrounded control master should exit due to expiry of the
261 * ControlPersist timeout. Sets it to 0 if we are not a backgrounded
262 * control master process, or if there is no ControlPersist timeout.
265 set_control_persist_exit_time(void)
267 if (muxserver_sock == -1 || !options.control_persist
268 || options.control_persist_timeout == 0) {
269 /* not using a ControlPersist timeout */
270 control_persist_exit_time = 0;
271 } else if (channel_still_open()) {
272 /* some client connections are still open */
273 if (control_persist_exit_time > 0)
274 debug2("%s: cancel scheduled exit", __func__);
275 control_persist_exit_time = 0;
276 } else if (control_persist_exit_time <= 0) {
277 /* a client connection has recently closed */
278 control_persist_exit_time = monotime() +
279 (time_t)options.control_persist_timeout;
280 debug2("%s: schedule exit in %d seconds", __func__,
281 options.control_persist_timeout);
283 /* else we are already counting down to the timeout */
286 #define SSH_X11_VALID_DISPLAY_CHARS ":/.-_"
288 client_x11_display_valid(const char *display)
292 dlen = strlen(display);
293 for (i = 0; i < dlen; i++) {
294 if (!isalnum((u_char)display[i]) &&
295 strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) {
296 debug("Invalid character '%c' in DISPLAY", display[i]);
303 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
305 client_x11_get_proto(const char *display, const char *xauth_path,
306 u_int trusted, u_int timeout, char **_proto, char **_data)
311 static char proto[512], data[512];
313 int got_data = 0, generated = 0, do_unlink = 0, i;
314 char *xauthdir, *xauthfile;
318 xauthdir = xauthfile = NULL;
321 proto[0] = data[0] = '\0';
323 if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
324 debug("No xauth program.");
325 } else if (!client_x11_display_valid(display)) {
326 logit("DISPLAY '%s' invalid, falling back to fake xauth data",
329 if (display == NULL) {
330 debug("x11_get_proto: DISPLAY not set");
334 * Handle FamilyLocal case where $DISPLAY does
335 * not match an authorization entry. For this we
336 * just try "xauth list unix:displaynum.screennum".
337 * XXX: "localhost" match to determine FamilyLocal
340 if (strncmp(display, "localhost:", 10) == 0) {
341 snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
346 xauthdir = xmalloc(MAXPATHLEN);
347 xauthfile = xmalloc(MAXPATHLEN);
348 mktemp_proto(xauthdir, MAXPATHLEN);
349 if (mkdtemp(xauthdir) != NULL) {
351 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
353 snprintf(cmd, sizeof(cmd),
354 "%s -f %s generate %s " SSH_X11_PROTO
355 " untrusted timeout %u 2>" _PATH_DEVNULL,
356 xauth_path, xauthfile, display, timeout);
357 debug2("x11_get_proto: %s", cmd);
358 if (system(cmd) == 0)
360 if (x11_refuse_time == 0) {
361 now = monotime() + 1;
362 if (UINT_MAX - timeout < now)
363 x11_refuse_time = UINT_MAX;
365 x11_refuse_time = now + timeout;
371 * When in untrusted mode, we read the cookie only if it was
372 * successfully generated as an untrusted one in the step
375 if (trusted || generated) {
376 snprintf(cmd, sizeof(cmd),
377 "%s %s%s list %s 2>" _PATH_DEVNULL,
379 generated ? "-f " : "" ,
380 generated ? xauthfile : "",
382 debug2("x11_get_proto: %s", cmd);
384 if (f && fgets(line, sizeof(line), f) &&
385 sscanf(line, "%*s %511s %511s", proto, data) == 2)
390 error("Warning: untrusted X11 forwarding setup failed: "
391 "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 explicit_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, server_alive_time = 0, now = monotime();
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 server_alive_time = now + options.server_alive_interval;
639 if (options.rekey_interval > 0 && compat20 && !rekeying)
640 timeout_secs = MIN(timeout_secs, packet_get_rekey_timeout());
641 set_control_persist_exit_time();
642 if (control_persist_exit_time > 0) {
643 timeout_secs = MIN(timeout_secs,
644 control_persist_exit_time - now);
645 if (timeout_secs < 0)
648 if (minwait_secs != 0)
649 timeout_secs = MIN(timeout_secs, (int)minwait_secs);
650 if (timeout_secs == INT_MAX)
653 tv.tv_sec = timeout_secs;
658 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
663 * We have to clear the select masks, because we return.
664 * We have to return, because the mainloop checks for the flags
665 * set by the signal handlers.
667 memset(*readsetp, 0, *nallocp);
668 memset(*writesetp, 0, *nallocp);
672 /* Note: we might still have data in the buffers. */
673 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
674 buffer_append(&stderr_buffer, buf, strlen(buf));
676 } else if (ret == 0) {
678 * Timeout. Could have been either keepalive or rekeying.
679 * Keepalive we check here, rekeying is checked in clientloop.
681 if (server_alive_time != 0 && server_alive_time <= monotime())
682 server_alive_check();
688 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
690 /* Flush stdout and stderr buffers. */
691 if (buffer_len(bout) > 0)
692 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
694 if (buffer_len(berr) > 0)
695 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
698 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
701 * Free (and clear) the buffer to reduce the amount of data that gets
708 /* Send the suspend signal to the program itself. */
709 kill(getpid(), SIGTSTP);
711 /* Reset window sizes in case they have changed */
712 received_window_change_signal = 1;
714 /* OK, we have been continued by the user. Reinitialize buffers. */
719 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
723 client_process_net_input(fd_set *readset)
726 char buf[SSH_IOBUFSZ];
729 * Read input from the server, and add any such data to the buffer of
730 * the packet subsystem.
732 if (FD_ISSET(connection_in, readset)) {
733 /* Read as much as possible. */
734 len = roaming_read(connection_in, buf, sizeof(buf), &cont);
735 if (len == 0 && cont == 0) {
737 * Received EOF. The remote host has closed the
740 snprintf(buf, sizeof buf,
741 "Connection to %.300s closed by remote host.\r\n",
743 buffer_append(&stderr_buffer, buf, strlen(buf));
748 * There is a kernel bug on Solaris that causes select to
749 * sometimes wake up even though there is no data available.
752 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
757 * An error has encountered. Perhaps there is a
760 snprintf(buf, sizeof buf,
761 "Read from remote host %.300s: %.100s\r\n",
762 host, strerror(errno));
763 buffer_append(&stderr_buffer, buf, strlen(buf));
767 packet_process_incoming(buf, len);
772 client_status_confirm(int type, Channel *c, void *ctx)
774 struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
779 * If a TTY was explicitly requested, then a failure to allocate
782 if (cr->action == CONFIRM_TTY &&
783 (options.request_tty == REQUEST_TTY_FORCE ||
784 options.request_tty == REQUEST_TTY_YES))
785 cr->action = CONFIRM_CLOSE;
787 /* XXX supress on mux _client_ quietmode */
788 tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
789 c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
791 if (type == SSH2_MSG_CHANNEL_SUCCESS) {
792 debug2("%s request accepted on channel %d",
793 cr->request_type, c->self);
794 } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
796 snprintf(errmsg, sizeof(errmsg),
797 "%s request failed\r\n", cr->request_type);
799 snprintf(errmsg, sizeof(errmsg),
800 "%s request failed on channel %d",
801 cr->request_type, c->self);
803 /* If error occurred on primary session channel, then exit */
804 if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
807 * If error occurred on mux client, append to
811 buffer_append(&c->extended, errmsg,
815 if (cr->action == CONFIRM_TTY) {
817 * If a TTY allocation error occurred, then arrange
818 * for the correct TTY to leave raw mode.
820 if (c->self == session_ident)
823 mux_tty_alloc_failed(c);
824 } else if (cr->action == CONFIRM_CLOSE) {
826 chan_write_failed(c);
833 client_abandon_status_confirm(Channel *c, void *ctx)
839 client_expect_confirm(int id, const char *request,
840 enum confirm_action action)
842 struct channel_reply_ctx *cr = xcalloc(1, sizeof(*cr));
844 cr->request_type = request;
847 channel_register_status_confirm(id, client_status_confirm,
848 client_abandon_status_confirm, cr);
852 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
854 struct global_confirm *gc, *last_gc;
856 /* Coalesce identical callbacks */
857 last_gc = TAILQ_LAST(&global_confirms, global_confirms);
858 if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
859 if (++last_gc->ref_count >= INT_MAX)
860 fatal("%s: last_gc->ref_count = %d",
861 __func__, last_gc->ref_count);
865 gc = xcalloc(1, sizeof(*gc));
869 TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
873 process_cmdline(void)
875 void (*handler)(int);
876 char *s, *cmd, *cancel_host;
877 int delete = 0, local = 0, remote = 0, dynamic = 0;
881 memset(&fwd, 0, sizeof(fwd));
882 fwd.listen_host = fwd.connect_host = NULL;
884 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
885 handler = signal(SIGINT, SIG_IGN);
886 cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
889 while (isspace((u_char)*s))
892 s++; /* Skip cmdline '-', if any */
896 if (*s == 'h' || *s == 'H' || *s == '?') {
898 logit(" -L[bind_address:]port:host:hostport "
899 "Request local forward");
900 logit(" -R[bind_address:]port:host:hostport "
901 "Request remote forward");
902 logit(" -D[bind_address:]port "
903 "Request dynamic forward");
904 logit(" -KL[bind_address:]port "
905 "Cancel local forward");
906 logit(" -KR[bind_address:]port "
907 "Cancel remote forward");
908 logit(" -KD[bind_address:]port "
909 "Cancel dynamic forward");
910 if (!options.permit_local_command)
913 "Execute local command");
917 if (*s == '!' && options.permit_local_command) {
934 logit("Invalid command.");
938 if (delete && !compat20) {
939 logit("Not supported for SSH protocol version 1.");
943 while (isspace((u_char)*++s))
946 /* XXX update list of forwards in options */
949 cancel_host = hpdelim(&s); /* may be NULL */
951 cancel_port = a2port(s);
952 cancel_host = cleanhostname(cancel_host);
954 cancel_port = a2port(cancel_host);
957 if (cancel_port <= 0) {
958 logit("Bad forwarding close port");
962 ok = channel_request_rforward_cancel(cancel_host,
965 ok = channel_cancel_lport_listener(cancel_host,
966 cancel_port, 0, options.gateway_ports) > 0;
968 ok = channel_cancel_lport_listener(cancel_host,
969 cancel_port, CHANNEL_CANCEL_PORT_STATIC,
970 options.gateway_ports) > 0;
972 logit("Unkown port forwarding.");
975 logit("Canceled forwarding.");
977 if (!parse_forward(&fwd, s, dynamic, remote)) {
978 logit("Bad forwarding specification.");
981 if (local || dynamic) {
982 if (!channel_setup_local_fwd_listener(fwd.listen_host,
983 fwd.listen_port, fwd.connect_host,
984 fwd.connect_port, options.gateway_ports)) {
985 logit("Port forwarding failed.");
989 if (channel_request_remote_forwarding(fwd.listen_host,
990 fwd.listen_port, fwd.connect_host,
991 fwd.connect_port) < 0) {
992 logit("Port forwarding failed.");
996 logit("Forwarding port.");
1000 signal(SIGINT, handler);
1001 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1003 free(fwd.listen_host);
1004 free(fwd.connect_host);
1007 /* reasons to suppress output of an escape command in help output */
1008 #define SUPPRESS_NEVER 0 /* never suppress, always show */
1009 #define SUPPRESS_PROTO1 1 /* don't show in protocol 1 sessions */
1010 #define SUPPRESS_MUXCLIENT 2 /* don't show in mux client sessions */
1011 #define SUPPRESS_MUXMASTER 4 /* don't show in mux master sessions */
1012 #define SUPPRESS_SYSLOG 8 /* don't show when logging to syslog */
1013 struct escape_help_text {
1018 static struct escape_help_text esc_txt[] = {
1019 {".", "terminate session", SUPPRESS_MUXMASTER},
1020 {".", "terminate connection (and any multiplexed sessions)",
1021 SUPPRESS_MUXCLIENT},
1022 {"B", "send a BREAK to the remote system", SUPPRESS_PROTO1},
1023 {"C", "open a command line", SUPPRESS_MUXCLIENT},
1024 {"R", "request rekey", SUPPRESS_PROTO1},
1025 {"V/v", "decrease/increase verbosity (LogLevel)", SUPPRESS_MUXCLIENT},
1026 {"^Z", "suspend ssh", SUPPRESS_MUXCLIENT},
1027 {"#", "list forwarded connections", SUPPRESS_NEVER},
1028 {"&", "background ssh (when waiting for connections to terminate)",
1029 SUPPRESS_MUXCLIENT},
1030 {"?", "this message", SUPPRESS_NEVER},
1034 print_escape_help(Buffer *b, int escape_char, int protocol2, int mux_client,
1037 unsigned int i, suppress_flags;
1040 snprintf(string, sizeof string, "%c?\r\n"
1041 "Supported escape sequences:\r\n", escape_char);
1042 buffer_append(b, string, strlen(string));
1044 suppress_flags = (protocol2 ? 0 : SUPPRESS_PROTO1) |
1045 (mux_client ? SUPPRESS_MUXCLIENT : 0) |
1046 (mux_client ? 0 : SUPPRESS_MUXMASTER) |
1047 (using_stderr ? 0 : SUPPRESS_SYSLOG);
1049 for (i = 0; i < sizeof(esc_txt)/sizeof(esc_txt[0]); i++) {
1050 if (esc_txt[i].flags & suppress_flags)
1052 snprintf(string, sizeof string, " %c%-3s - %s\r\n",
1053 escape_char, esc_txt[i].cmd, esc_txt[i].text);
1054 buffer_append(b, string, strlen(string));
1057 snprintf(string, sizeof string,
1058 " %c%c - send the escape character by typing it twice\r\n"
1059 "(Note that escapes are only recognized immediately after "
1060 "newline.)\r\n", escape_char, escape_char);
1061 buffer_append(b, string, strlen(string));
1065 * Process the characters one by one, call with c==NULL for proto1 case.
1068 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
1077 int *escape_pendingp, escape_char;
1078 struct escape_filter_ctx *efc;
1081 escape_pendingp = &escape_pending1;
1082 escape_char = escape_char1;
1084 if (c->filter_ctx == NULL)
1086 efc = (struct escape_filter_ctx *)c->filter_ctx;
1087 escape_pendingp = &efc->escape_pending;
1088 escape_char = efc->escape_char;
1094 for (i = 0; i < (u_int)len; i++) {
1095 /* Get one character at a time. */
1098 if (*escape_pendingp) {
1099 /* We have previously seen an escape character. */
1100 /* Clear the flag now. */
1101 *escape_pendingp = 0;
1103 /* Process the escaped character. */
1106 /* Terminate the connection. */
1107 snprintf(string, sizeof string, "%c.\r\n",
1109 buffer_append(berr, string, strlen(string));
1111 if (c && c->ctl_chan != -1) {
1112 chan_read_failed(c);
1113 chan_write_failed(c);
1115 c->detach_user(c->self, NULL);
1116 c->type = SSH_CHANNEL_ABANDONED;
1117 buffer_clear(&c->input);
1125 /* XXX support this for mux clients */
1126 if (c && c->ctl_chan != -1) {
1130 snprintf(b, sizeof b, "^Z");
1132 snprintf(b, sizeof b, "%c", ch);
1133 snprintf(string, sizeof string,
1134 "%c%s escape not available to "
1135 "multiplexed sessions\r\n",
1137 buffer_append(berr, string,
1141 /* Suspend the program. Inform the user */
1142 snprintf(string, sizeof string,
1143 "%c^Z [suspend ssh]\r\n", escape_char);
1144 buffer_append(berr, string, strlen(string));
1146 /* Restore terminal modes and suspend. */
1147 client_suspend_self(bin, bout, berr);
1149 /* We have been continued. */
1154 snprintf(string, sizeof string,
1155 "%cB\r\n", escape_char);
1156 buffer_append(berr, string,
1158 channel_request_start(c->self,
1160 packet_put_int(1000);
1167 if (datafellows & SSH_BUG_NOREKEY)
1168 logit("Server does not "
1169 "support re-keying");
1178 if (c && c->ctl_chan != -1)
1180 if (!log_is_on_stderr()) {
1181 snprintf(string, sizeof string,
1182 "%c%c [Logging to syslog]\r\n",
1184 buffer_append(berr, string,
1188 if (ch == 'V' && options.log_level >
1190 log_change_level(--options.log_level);
1191 if (ch == 'v' && options.log_level <
1192 SYSLOG_LEVEL_DEBUG3)
1193 log_change_level(++options.log_level);
1194 snprintf(string, sizeof string,
1195 "%c%c [LogLevel %s]\r\n", escape_char, ch,
1196 log_level_name(options.log_level));
1197 buffer_append(berr, string, strlen(string));
1201 if (c && c->ctl_chan != -1)
1204 * Detach the program (continue to serve
1205 * connections, but put in background and no
1206 * more new connections).
1208 /* Restore tty modes. */
1210 options.request_tty == REQUEST_TTY_FORCE);
1212 /* Stop listening for new connections. */
1213 channel_stop_listening();
1215 snprintf(string, sizeof string,
1216 "%c& [backgrounded]\n", escape_char);
1217 buffer_append(berr, string, strlen(string));
1219 /* Fork into background. */
1222 error("fork: %.100s", strerror(errno));
1225 if (pid != 0) { /* This is the parent. */
1226 /* The parent just exits. */
1229 /* The child continues serving connections. */
1231 buffer_append(bin, "\004", 1);
1232 /* fake EOF on stdin */
1234 } else if (!stdin_eof) {
1236 * Sending SSH_CMSG_EOF alone does not
1237 * always appear to be enough. So we
1238 * try to send an EOF character first.
1240 packet_start(SSH_CMSG_STDIN_DATA);
1241 packet_put_string("\004", 1);
1245 if (buffer_len(bin) == 0) {
1246 packet_start(SSH_CMSG_EOF);
1253 print_escape_help(berr, escape_char, compat20,
1254 (c && c->ctl_chan != -1),
1255 log_is_on_stderr());
1259 snprintf(string, sizeof string, "%c#\r\n",
1261 buffer_append(berr, string, strlen(string));
1262 s = channel_open_message();
1263 buffer_append(berr, s, strlen(s));
1268 if (c && c->ctl_chan != -1)
1274 if (ch != escape_char) {
1275 buffer_put_char(bin, escape_char);
1278 /* Escaped characters fall through here */
1283 * The previous character was not an escape char.
1284 * Check if this is an escape.
1286 if (last_was_cr && ch == escape_char) {
1288 * It is. Set the flag and continue to
1291 *escape_pendingp = 1;
1297 * Normal character. Record whether it was a newline,
1298 * and append it to the buffer.
1300 last_was_cr = (ch == '\r' || ch == '\n');
1301 buffer_put_char(bin, ch);
1308 client_process_input(fd_set *readset)
1311 char buf[SSH_IOBUFSZ];
1313 /* Read input from stdin. */
1314 if (FD_ISSET(fileno(stdin), readset)) {
1315 /* Read as much as possible. */
1316 len = read(fileno(stdin), buf, sizeof(buf));
1318 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1319 return; /* we'll try again later */
1322 * Received EOF or error. They are treated
1323 * similarly, except that an error message is printed
1324 * if it was an error condition.
1327 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1329 buffer_append(&stderr_buffer, buf, strlen(buf));
1331 /* Mark that we have seen EOF. */
1334 * Send an EOF message to the server unless there is
1335 * data in the buffer. If there is data in the
1336 * buffer, no message will be sent now. Code
1337 * elsewhere will send the EOF when the buffer
1338 * becomes empty if stdin_eof is set.
1340 if (buffer_len(&stdin_buffer) == 0) {
1341 packet_start(SSH_CMSG_EOF);
1344 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1346 * Normal successful read, and no escape character.
1347 * Just append the data to buffer.
1349 buffer_append(&stdin_buffer, buf, len);
1352 * Normal, successful read. But we have an escape
1353 * character and have to process the characters one
1356 if (process_escapes(NULL, &stdin_buffer,
1357 &stdout_buffer, &stderr_buffer, buf, len) == -1)
1364 client_process_output(fd_set *writeset)
1369 /* Write buffered output to stdout. */
1370 if (FD_ISSET(fileno(stdout), writeset)) {
1371 /* Write as much data as possible. */
1372 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1373 buffer_len(&stdout_buffer));
1375 if (errno == EINTR || errno == EAGAIN ||
1376 errno == EWOULDBLOCK)
1380 * An error or EOF was encountered. Put an
1381 * error message to stderr buffer.
1383 snprintf(buf, sizeof buf,
1384 "write stdout: %.50s\r\n", strerror(errno));
1385 buffer_append(&stderr_buffer, buf, strlen(buf));
1390 /* Consume printed data from the buffer. */
1391 buffer_consume(&stdout_buffer, len);
1393 /* Write buffered output to stderr. */
1394 if (FD_ISSET(fileno(stderr), writeset)) {
1395 /* Write as much data as possible. */
1396 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1397 buffer_len(&stderr_buffer));
1399 if (errno == EINTR || errno == EAGAIN ||
1400 errno == EWOULDBLOCK)
1404 * EOF or error, but can't even print
1411 /* Consume printed characters from the buffer. */
1412 buffer_consume(&stderr_buffer, len);
1417 * Get packets from the connection input buffer, and process them as long as
1418 * there are packets available.
1420 * Any unknown packets received during the actual
1421 * session cause the session to terminate. This is
1422 * intended to make debugging easier since no
1423 * confirmations are sent. Any compatible protocol
1424 * extensions must be negotiated during the
1425 * preparatory phase.
1429 client_process_buffered_input_packets(void)
1431 dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1432 compat20 ? xxx_kex : NULL);
1435 /* scan buf[] for '~' before sending data to the peer */
1437 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1439 client_new_escape_filter_ctx(int escape_char)
1441 struct escape_filter_ctx *ret;
1443 ret = xcalloc(1, sizeof(*ret));
1444 ret->escape_pending = 0;
1445 ret->escape_char = escape_char;
1449 /* Free the escape filter context on channel free */
1451 client_filter_cleanup(int cid, void *ctx)
1457 client_simple_escape_filter(Channel *c, char *buf, int len)
1459 if (c->extended_usage != CHAN_EXTENDED_WRITE)
1462 return process_escapes(c, &c->input, &c->output, &c->extended,
1467 client_channel_closed(int id, void *arg)
1469 channel_cancel_cleanup(id);
1471 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1475 * Implements the interactive session with the server. This is called after
1476 * the user has been authenticated, and a command has been started on the
1477 * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1478 * used as an escape character for terminating or suspending the session.
1482 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1484 fd_set *readset = NULL, *writeset = NULL;
1485 double start_time, total_time;
1486 int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1487 u_int64_t ibytes, obytes;
1491 debug("Entering interactive session.");
1493 start_time = get_current_time();
1495 /* Initialize variables. */
1496 escape_pending1 = 0;
1500 buffer_high = 64 * 1024;
1501 connection_in = packet_get_connection_in();
1502 connection_out = packet_get_connection_out();
1503 max_fd = MAX(connection_in, connection_out);
1506 /* enable nonblocking unless tty */
1507 if (!isatty(fileno(stdin)))
1508 set_nonblock(fileno(stdin));
1509 if (!isatty(fileno(stdout)))
1510 set_nonblock(fileno(stdout));
1511 if (!isatty(fileno(stderr)))
1512 set_nonblock(fileno(stderr));
1513 max_fd = MAX(max_fd, fileno(stdin));
1514 max_fd = MAX(max_fd, fileno(stdout));
1515 max_fd = MAX(max_fd, fileno(stderr));
1518 escape_char1 = escape_char_arg;
1520 /* Initialize buffers. */
1521 buffer_init(&stdin_buffer);
1522 buffer_init(&stdout_buffer);
1523 buffer_init(&stderr_buffer);
1525 client_init_dispatch();
1528 * Set signal handlers, (e.g. to restore non-blocking mode)
1529 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1531 if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1532 signal(SIGHUP, signal_handler);
1533 if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1534 signal(SIGINT, signal_handler);
1535 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1536 signal(SIGQUIT, signal_handler);
1537 if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1538 signal(SIGTERM, signal_handler);
1539 signal(SIGWINCH, window_change_handler);
1542 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1545 session_ident = ssh2_chan_id;
1546 if (session_ident != -1) {
1547 if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1548 channel_register_filter(session_ident,
1549 client_simple_escape_filter, NULL,
1550 client_filter_cleanup,
1551 client_new_escape_filter_ctx(
1554 channel_register_cleanup(session_ident,
1555 client_channel_closed, 0);
1558 /* Check if we should immediately send eof on stdin. */
1559 client_check_initial_eof_on_stdin();
1562 /* Main loop of the client for the interactive session mode. */
1563 while (!quit_pending) {
1565 /* Process buffered packets sent by the server. */
1566 client_process_buffered_input_packets();
1568 if (compat20 && session_closed && !channel_still_open())
1571 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1574 debug("rekeying in progress");
1577 * Make packets of buffered stdin data, and buffer
1578 * them for sending to the server.
1581 client_make_packets_from_stdin_data();
1584 * Make packets from buffered channel data, and
1585 * enqueue them for sending to the server.
1587 if (packet_not_very_much_data_to_write())
1588 channel_output_poll();
1591 * Check if the window size has changed, and buffer a
1592 * message about it to the server if so.
1594 client_check_window_change();
1600 * Wait until we have something to do (something becomes
1601 * available on one of the descriptors).
1604 client_wait_until_can_do_something(&readset, &writeset,
1605 &max_fd2, &nalloc, rekeying);
1610 /* Do channel operations unless rekeying in progress. */
1612 channel_after_select(readset, writeset);
1613 if (need_rekeying || packet_need_rekeying()) {
1614 debug("need rekeying");
1616 kex_send_kexinit(xxx_kex);
1621 /* Buffer input from the connection. */
1622 client_process_net_input(readset);
1628 /* Buffer data from stdin */
1629 client_process_input(readset);
1631 * Process output to stdout and stderr. Output to
1632 * the connection is processed elsewhere (above).
1634 client_process_output(writeset);
1637 if (session_resumed) {
1638 connection_in = packet_get_connection_in();
1639 connection_out = packet_get_connection_out();
1640 max_fd = MAX(max_fd, connection_out);
1641 max_fd = MAX(max_fd, connection_in);
1642 session_resumed = 0;
1646 * Send as much buffered packet data as possible to the
1649 if (FD_ISSET(connection_out, writeset))
1650 packet_write_poll();
1653 * If we are a backgrounded control master, and the
1654 * timeout has expired without any active client
1655 * connections, then quit.
1657 if (control_persist_exit_time > 0) {
1658 if (monotime() >= control_persist_exit_time) {
1659 debug("ControlPersist timeout expired");
1667 /* Terminate the session. */
1669 /* Stop watching for window change. */
1670 signal(SIGWINCH, SIG_DFL);
1673 packet_start(SSH2_MSG_DISCONNECT);
1674 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1675 packet_put_cstring("disconnected by user");
1676 packet_put_cstring(""); /* language tag */
1678 packet_write_wait();
1684 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1686 /* restore blocking io */
1687 if (!isatty(fileno(stdin)))
1688 unset_nonblock(fileno(stdin));
1689 if (!isatty(fileno(stdout)))
1690 unset_nonblock(fileno(stdout));
1691 if (!isatty(fileno(stderr)))
1692 unset_nonblock(fileno(stderr));
1695 * If there was no shell or command requested, there will be no remote
1696 * exit status to be returned. In that case, clear error code if the
1697 * connection was deliberately terminated at this end.
1699 if (no_shell_flag && received_signal == SIGTERM) {
1700 received_signal = 0;
1704 if (received_signal)
1705 fatal("Killed by signal %d.", (int) received_signal);
1708 * In interactive mode (with pseudo tty) display a message indicating
1709 * that the connection has been closed.
1711 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1712 snprintf(buf, sizeof buf,
1713 "Connection to %.64s closed.\r\n", host);
1714 buffer_append(&stderr_buffer, buf, strlen(buf));
1717 /* Output any buffered data for stdout. */
1718 if (buffer_len(&stdout_buffer) > 0) {
1719 len = atomicio(vwrite, fileno(stdout),
1720 buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1721 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1722 error("Write failed flushing stdout buffer.");
1724 buffer_consume(&stdout_buffer, len);
1727 /* Output any buffered data for stderr. */
1728 if (buffer_len(&stderr_buffer) > 0) {
1729 len = atomicio(vwrite, fileno(stderr),
1730 buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1731 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1732 error("Write failed flushing stderr buffer.");
1734 buffer_consume(&stderr_buffer, len);
1737 /* Clear and free any buffers. */
1738 memset(buf, 0, sizeof(buf));
1739 buffer_free(&stdin_buffer);
1740 buffer_free(&stdout_buffer);
1741 buffer_free(&stderr_buffer);
1743 /* Report bytes transferred, and transfer rates. */
1744 total_time = get_current_time() - start_time;
1745 packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1746 packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1747 verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1748 (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1750 verbose("Bytes per second: sent %.1f, received %.1f",
1751 obytes / total_time, ibytes / total_time);
1752 /* Return the exit status of the program. */
1753 debug("Exit status %d", exit_status);
1760 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1763 char *data = packet_get_string(&data_len);
1765 buffer_append(&stdout_buffer, data, data_len);
1766 explicit_bzero(data, data_len);
1770 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1773 char *data = packet_get_string(&data_len);
1775 buffer_append(&stderr_buffer, data, data_len);
1776 explicit_bzero(data, data_len);
1780 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1782 exit_status = packet_get_int();
1784 /* Acknowledge the exit. */
1785 packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1788 * Must wait for packet to be sent since we are
1791 packet_write_wait();
1792 /* Flag that we want to exit. */
1796 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1799 int remote_id, sock;
1801 /* Read the remote channel number from the message. */
1802 remote_id = packet_get_int();
1806 * Get a connection to the local authentication agent (this may again
1809 sock = ssh_get_authentication_socket();
1812 * If we could not connect the agent, send an error message back to
1813 * the server. This should never happen unless the agent dies,
1814 * because authentication forwarding is only enabled if we have an
1818 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1819 -1, 0, 0, 0, "authentication agent connection", 1);
1820 c->remote_id = remote_id;
1824 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1825 packet_put_int(remote_id);
1827 /* Send a confirmation to the remote host. */
1828 debug("Forwarding authentication connection.");
1829 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1830 packet_put_int(remote_id);
1831 packet_put_int(c->self);
1837 client_request_forwarded_tcpip(const char *request_type, int rchan)
1840 char *listen_address, *originator_address;
1841 u_short listen_port, originator_port;
1843 /* Get rest of the packet */
1844 listen_address = packet_get_string(NULL);
1845 listen_port = packet_get_int();
1846 originator_address = packet_get_string(NULL);
1847 originator_port = packet_get_int();
1850 debug("client_request_forwarded_tcpip: listen %s port %d, "
1851 "originator %s port %d", listen_address, listen_port,
1852 originator_address, originator_port);
1854 c = channel_connect_by_listen_address(listen_port,
1855 "forwarded-tcpip", originator_address);
1857 free(originator_address);
1858 free(listen_address);
1863 client_request_x11(const char *request_type, int rchan)
1867 u_short originator_port;
1870 if (!options.forward_x11) {
1871 error("Warning: ssh server tried X11 forwarding.");
1872 error("Warning: this is probably a break-in attempt by a "
1873 "malicious server.");
1876 if (x11_refuse_time != 0 && monotime() >= x11_refuse_time) {
1877 verbose("Rejected X11 connection after ForwardX11Timeout "
1881 originator = packet_get_string(NULL);
1882 if (datafellows & SSH_BUG_X11FWD) {
1883 debug2("buggy server: x11 request w/o originator_port");
1884 originator_port = 0;
1886 originator_port = packet_get_int();
1889 /* XXX check permission */
1890 debug("client_request_x11: request from %s %d", originator,
1893 sock = x11_connect_display();
1896 if (options.hpn_disabled)
1897 c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1898 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1901 c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1902 options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT,
1909 client_request_agent(const char *request_type, int rchan)
1914 if (!options.forward_agent) {
1915 error("Warning: ssh server tried agent forwarding.");
1916 error("Warning: this is probably a break-in attempt by a "
1917 "malicious server.");
1920 sock = ssh_get_authentication_socket();
1923 if (options.hpn_disabled)
1924 c = channel_new("authentication agent connection",
1925 SSH_CHANNEL_OPEN, sock, sock, -1,
1926 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1927 "authentication agent connection", 1);
1929 c = channel_new("authentication agent connection",
1930 SSH_CHANNEL_OPEN, sock, sock, -1,
1931 options.hpn_buffer_size, options.hpn_buffer_size, 0,
1932 "authentication agent connection", 1);
1938 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1943 if (tun_mode == SSH_TUNMODE_NO)
1947 error("Tunnel forwarding is not supported for protocol 1");
1951 debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1953 /* Open local tunnel device */
1954 if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1955 error("Tunnel device open failed.");
1959 if (options.hpn_disabled)
1960 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1961 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1964 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1965 options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
1969 #if defined(SSH_TUN_FILTER)
1970 if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1971 channel_register_filter(c->self, sys_tun_infilter,
1972 sys_tun_outfilter, NULL, NULL);
1975 packet_start(SSH2_MSG_CHANNEL_OPEN);
1976 packet_put_cstring("tun@openssh.com");
1977 packet_put_int(c->self);
1978 packet_put_int(c->local_window_max);
1979 packet_put_int(c->local_maxpacket);
1980 packet_put_int(tun_mode);
1981 packet_put_int(remote_tun);
1987 /* XXXX move to generic input handler */
1989 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1994 u_int rmaxpack, rwindow, len;
1996 ctype = packet_get_string(&len);
1997 rchan = packet_get_int();
1998 rwindow = packet_get_int();
1999 rmaxpack = packet_get_int();
2001 debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
2002 ctype, rchan, rwindow, rmaxpack);
2004 if (strcmp(ctype, "forwarded-tcpip") == 0) {
2005 c = client_request_forwarded_tcpip(ctype, rchan);
2006 } else if (strcmp(ctype, "x11") == 0) {
2007 c = client_request_x11(ctype, rchan);
2008 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
2009 c = client_request_agent(ctype, rchan);
2011 /* XXX duplicate : */
2013 debug("confirm %s", ctype);
2014 c->remote_id = rchan;
2015 c->remote_window = rwindow;
2016 c->remote_maxpacket = rmaxpack;
2017 if (c->type != SSH_CHANNEL_CONNECTING) {
2018 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
2019 packet_put_int(c->remote_id);
2020 packet_put_int(c->self);
2021 packet_put_int(c->local_window);
2022 packet_put_int(c->local_maxpacket);
2026 debug("failure %s", ctype);
2027 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
2028 packet_put_int(rchan);
2029 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
2030 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
2031 packet_put_cstring("open failed");
2032 packet_put_cstring("");
2039 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
2042 int exitval, id, reply, success = 0;
2045 id = packet_get_int();
2046 rtype = packet_get_string(NULL);
2047 reply = packet_get_char();
2049 debug("client_input_channel_req: channel %d rtype %s reply %d",
2053 error("client_input_channel_req: request for channel -1");
2054 } else if ((c = channel_lookup(id)) == NULL) {
2055 error("client_input_channel_req: channel %d: "
2056 "unknown channel", id);
2057 } else if (strcmp(rtype, "eow@openssh.com") == 0) {
2060 } else if (strcmp(rtype, "exit-status") == 0) {
2061 exitval = packet_get_int();
2062 if (c->ctl_chan != -1) {
2063 mux_exit_message(c, exitval);
2065 } else if (id == session_ident) {
2066 /* Record exit value of local session */
2068 exit_status = exitval;
2070 /* Probably for a mux channel that has already closed */
2071 debug("%s: no sink for exit-status on channel %d",
2076 if (reply && c != NULL) {
2077 packet_start(success ?
2078 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
2079 packet_put_int(c->remote_id);
2085 client_input_global_request(int type, u_int32_t seq, void *ctxt)
2091 rtype = packet_get_string(NULL);
2092 want_reply = packet_get_char();
2093 debug("client_input_global_request: rtype %s want_reply %d",
2096 packet_start(success ?
2097 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2099 packet_write_wait();
2105 client_session2_setup(int id, int want_tty, int want_subsystem,
2106 const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2111 debug2("%s: id %d", __func__, id);
2113 if ((c = channel_lookup(id)) == NULL)
2114 fatal("client_session2_setup: channel %d: unknown channel", id);
2116 packet_set_interactive(want_tty,
2117 options.ip_qos_interactive, options.ip_qos_bulk);
2122 /* Store window size in the packet. */
2123 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2124 memset(&ws, 0, sizeof(ws));
2126 channel_request_start(id, "pty-req", 1);
2127 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2128 packet_put_cstring(term != NULL ? term : "");
2129 packet_put_int((u_int)ws.ws_col);
2130 packet_put_int((u_int)ws.ws_row);
2131 packet_put_int((u_int)ws.ws_xpixel);
2132 packet_put_int((u_int)ws.ws_ypixel);
2134 tiop = get_saved_tio();
2135 tty_make_modes(-1, tiop);
2137 /* XXX wait for reply */
2141 /* Transfer any environment variables from client to server */
2142 if (options.num_send_env != 0 && env != NULL) {
2146 debug("Sending environment.");
2147 for (i = 0; env[i] != NULL; i++) {
2149 name = xstrdup(env[i]);
2150 if ((val = strchr(name, '=')) == NULL) {
2157 for (j = 0; j < options.num_send_env; j++) {
2158 if (match_pattern(name, options.send_env[j])) {
2164 debug3("Ignored env %s", name);
2169 debug("Sending env %s = %s", name, val);
2170 channel_request_start(id, "env", 0);
2171 packet_put_cstring(name);
2172 packet_put_cstring(val);
2178 len = buffer_len(cmd);
2182 if (want_subsystem) {
2183 debug("Sending subsystem: %.*s",
2184 len, (u_char*)buffer_ptr(cmd));
2185 channel_request_start(id, "subsystem", 1);
2186 client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2188 debug("Sending command: %.*s",
2189 len, (u_char*)buffer_ptr(cmd));
2190 channel_request_start(id, "exec", 1);
2191 client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2193 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2196 channel_request_start(id, "shell", 1);
2197 client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2203 client_init_dispatch_20(void)
2205 dispatch_init(&dispatch_protocol_error);
2207 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2208 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2209 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2210 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2211 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2212 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2213 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2214 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2215 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2216 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2217 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2218 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2221 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2223 /* global request reply messages */
2224 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2225 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2229 client_init_dispatch_13(void)
2231 dispatch_init(NULL);
2232 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2233 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2234 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2235 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2236 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2237 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2238 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2239 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2240 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2242 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2243 &client_input_agent_open : &deny_input_open);
2244 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2245 &x11_input_open : &deny_input_open);
2249 client_init_dispatch_15(void)
2251 client_init_dispatch_13();
2252 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2253 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2257 client_init_dispatch(void)
2260 client_init_dispatch_20();
2262 client_init_dispatch_13();
2264 client_init_dispatch_15();
2268 client_stop_mux(void)
2270 if (options.control_path != NULL && muxserver_sock != -1)
2271 unlink(options.control_path);
2273 * If we are in persist mode, or don't have a shell, signal that we
2274 * should close when all active channels are closed.
2276 if (options.control_persist || no_shell_flag) {
2278 setproctitle("[stopped mux]");
2282 /* client specific fatal cleanup */
2286 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2287 leave_non_blocking();
2288 if (options.control_path != NULL && muxserver_sock != -1)
2289 unlink(options.control_path);
2290 ssh_kill_proxy_command();