1 /* $OpenBSD: clientloop.c,v 1.240 2012/06/20 04:42:58 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.
65 #include <sys/types.h>
66 #include <sys/ioctl.h>
67 #include <sys/param.h>
68 #ifdef HAVE_SYS_STAT_H
69 # include <sys/stat.h>
71 #ifdef HAVE_SYS_TIME_H
72 # include <sys/time.h>
74 #include <sys/socket.h>
90 #include "openbsd-compat/sys-queue.h"
104 #include "readconf.h"
105 #include "clientloop.h"
106 #include "sshconnect.h"
108 #include "atomicio.h"
116 extern Options options;
118 /* Flag indicating that stdin should be redirected from /dev/null. */
119 extern int stdin_null_flag;
121 /* Flag indicating that no shell has been requested */
122 extern int no_shell_flag;
125 extern int muxserver_sock; /* XXX use mux_client_cleanup() instead */
128 * Name of the host we are connecting to. This is the name given on the
129 * command line, or the HostName specified for the user-supplied name in a
130 * configuration file.
135 * Flag to indicate that we have received a window change signal which has
136 * not yet been processed. This will cause a message indicating the new
137 * window size to be sent to the server a little later. This is volatile
138 * because this is updated in a signal handler.
140 static volatile sig_atomic_t received_window_change_signal = 0;
141 static volatile sig_atomic_t received_signal = 0;
143 /* Flag indicating whether the user's terminal is in non-blocking mode. */
144 static int in_non_blocking_mode = 0;
146 /* Time when backgrounded control master using ControlPersist should exit */
147 static time_t control_persist_exit_time = 0;
149 /* Common data for the client loop code. */
150 volatile sig_atomic_t quit_pending; /* Set non-zero to quit the loop. */
151 static int escape_char1; /* Escape character. (proto1 only) */
152 static int escape_pending1; /* Last character was an escape (proto1 only) */
153 static int last_was_cr; /* Last character was a newline. */
154 static int exit_status; /* Used to store the command exit status. */
155 static int stdin_eof; /* EOF has been encountered on stderr. */
156 static Buffer stdin_buffer; /* Buffer for stdin data. */
157 static Buffer stdout_buffer; /* Buffer for stdout data. */
158 static Buffer stderr_buffer; /* Buffer for stderr data. */
159 static u_int buffer_high; /* Soft max buffer size. */
160 static int connection_in; /* Connection to server (input). */
161 static int connection_out; /* Connection to server (output). */
162 static int need_rekeying; /* Set to non-zero if rekeying is requested. */
163 static int session_closed; /* In SSH2: login session closed. */
164 static int x11_refuse_time; /* If >0, refuse x11 opens after this time. */
166 static void client_init_dispatch(void);
167 int session_ident = -1;
169 int session_resumed = 0;
171 /* Track escape per proto2 channel */
172 struct escape_filter_ctx {
177 /* Context for channel confirmation replies */
178 struct channel_reply_ctx {
179 const char *request_type;
181 enum confirm_action action;
184 /* Global request success/failure callbacks */
185 struct global_confirm {
186 TAILQ_ENTRY(global_confirm) entry;
187 global_confirm_cb *cb;
191 TAILQ_HEAD(global_confirms, global_confirm);
192 static struct global_confirms global_confirms =
193 TAILQ_HEAD_INITIALIZER(global_confirms);
198 void ssh_process_session2_setup(int, int, int, Buffer *);
200 /* Restores stdin to blocking mode. */
203 leave_non_blocking(void)
205 if (in_non_blocking_mode) {
206 unset_nonblock(fileno(stdin));
207 in_non_blocking_mode = 0;
211 /* Puts stdin terminal in non-blocking mode. */
214 enter_non_blocking(void)
216 in_non_blocking_mode = 1;
217 set_nonblock(fileno(stdin));
221 * Signal handler for the window change signal (SIGWINCH). This just sets a
222 * flag indicating that the window has changed.
226 window_change_handler(int sig)
228 received_window_change_signal = 1;
229 signal(SIGWINCH, window_change_handler);
233 * Signal handler for signals that cause the program to terminate. These
234 * signals must be trapped to restore terminal modes.
238 signal_handler(int sig)
240 received_signal = sig;
245 * Returns current time in seconds from Jan 1, 1970 with the maximum
246 * available resolution.
250 get_current_time(void)
253 gettimeofday(&tv, NULL);
254 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
258 * Sets control_persist_exit_time to the absolute time when the
259 * backgrounded control master should exit due to expiry of the
260 * ControlPersist timeout. Sets it to 0 if we are not a backgrounded
261 * control master process, or if there is no ControlPersist timeout.
264 set_control_persist_exit_time(void)
266 if (muxserver_sock == -1 || !options.control_persist
267 || options.control_persist_timeout == 0) {
268 /* not using a ControlPersist timeout */
269 control_persist_exit_time = 0;
270 } else if (channel_still_open()) {
271 /* some client connections are still open */
272 if (control_persist_exit_time > 0)
273 debug2("%s: cancel scheduled exit", __func__);
274 control_persist_exit_time = 0;
275 } else if (control_persist_exit_time <= 0) {
276 /* a client connection has recently closed */
277 control_persist_exit_time = time(NULL) +
278 (time_t)options.control_persist_timeout;
279 debug2("%s: schedule exit in %d seconds", __func__,
280 options.control_persist_timeout);
282 /* else we are already counting down to the timeout */
285 #define SSH_X11_VALID_DISPLAY_CHARS ":/.-_"
287 client_x11_display_valid(const char *display)
291 dlen = strlen(display);
292 for (i = 0; i < dlen; i++) {
293 if (!isalnum(display[i]) &&
294 strchr(SSH_X11_VALID_DISPLAY_CHARS, display[i]) == NULL) {
295 debug("Invalid character '%c' in DISPLAY", display[i]);
302 #define SSH_X11_PROTO "MIT-MAGIC-COOKIE-1"
304 client_x11_get_proto(const char *display, const char *xauth_path,
305 u_int trusted, u_int timeout, char **_proto, char **_data)
310 static char proto[512], data[512];
312 int got_data = 0, generated = 0, do_unlink = 0, i;
313 char *xauthdir, *xauthfile;
317 xauthdir = xauthfile = NULL;
320 proto[0] = data[0] = '\0';
322 if (xauth_path == NULL ||(stat(xauth_path, &st) == -1)) {
323 debug("No xauth program.");
324 } else if (!client_x11_display_valid(display)) {
325 logit("DISPLAY '%s' invalid, falling back to fake xauth data",
328 if (display == NULL) {
329 debug("x11_get_proto: DISPLAY not set");
333 * Handle FamilyLocal case where $DISPLAY does
334 * not match an authorization entry. For this we
335 * just try "xauth list unix:displaynum.screennum".
336 * XXX: "localhost" match to determine FamilyLocal
339 if (strncmp(display, "localhost:", 10) == 0) {
340 snprintf(xdisplay, sizeof(xdisplay), "unix:%s",
345 xauthdir = xmalloc(MAXPATHLEN);
346 xauthfile = xmalloc(MAXPATHLEN);
347 mktemp_proto(xauthdir, MAXPATHLEN);
348 if (mkdtemp(xauthdir) != NULL) {
350 snprintf(xauthfile, MAXPATHLEN, "%s/xauthfile",
352 snprintf(cmd, sizeof(cmd),
353 "%s -f %s generate %s " SSH_X11_PROTO
354 " untrusted timeout %u 2>" _PATH_DEVNULL,
355 xauth_path, xauthfile, display, timeout);
356 debug2("x11_get_proto: %s", cmd);
357 if (system(cmd) == 0)
359 if (x11_refuse_time == 0) {
360 now = time(NULL) + 1;
361 if (UINT_MAX - timeout < now)
362 x11_refuse_time = UINT_MAX;
364 x11_refuse_time = now + timeout;
370 * When in untrusted mode, we read the cookie only if it was
371 * successfully generated as an untrusted one in the step
374 if (trusted || generated) {
375 snprintf(cmd, sizeof(cmd),
376 "%s %s%s list %s 2>" _PATH_DEVNULL,
378 generated ? "-f " : "" ,
379 generated ? xauthfile : "",
381 debug2("x11_get_proto: %s", cmd);
383 if (f && fgets(line, sizeof(line), f) &&
384 sscanf(line, "%*s %511s %511s", proto, data) == 2)
389 error("Warning: untrusted X11 forwarding setup failed: "
390 "xauth key data not generated");
403 * If we didn't get authentication data, just make up some
404 * data. The forwarding code will check the validity of the
405 * response anyway, and substitute this data. The X11
406 * server, however, will ignore this fake data and use
407 * whatever authentication mechanisms it was using otherwise
408 * for the local connection.
413 logit("Warning: No xauth data; "
414 "using fake authentication data for X11 forwarding.");
415 strlcpy(proto, SSH_X11_PROTO, sizeof proto);
416 for (i = 0; i < 16; i++) {
419 snprintf(data + 2 * i, sizeof data - 2 * i, "%02x",
427 * This is called when the interactive is entered. This checks if there is
428 * an EOF coming on stdin. We must check this explicitly, as select() does
429 * not appear to wake up when redirecting from /dev/null.
433 client_check_initial_eof_on_stdin(void)
439 * If standard input is to be "redirected from /dev/null", we simply
440 * mark that we have seen an EOF and send an EOF message to the
441 * server. Otherwise, we try to read a single character; it appears
442 * that for some files, such /dev/null, select() never wakes up for
443 * read for this descriptor, which means that we never get EOF. This
444 * way we will get the EOF if stdin comes from /dev/null or similar.
446 if (stdin_null_flag) {
447 /* Fake EOF on stdin. */
448 debug("Sending eof.");
450 packet_start(SSH_CMSG_EOF);
453 enter_non_blocking();
455 /* Check for immediate EOF on stdin. */
456 len = read(fileno(stdin), buf, 1);
459 * EOF. Record that we have seen it and send
462 debug("Sending eof.");
464 packet_start(SSH_CMSG_EOF);
466 } else if (len > 0) {
468 * Got data. We must store the data in the buffer,
469 * and also process it as an escape character if
472 if ((u_char) buf[0] == escape_char1)
475 buffer_append(&stdin_buffer, buf, 1);
477 leave_non_blocking();
483 * Make packets from buffered stdin data, and buffer them for sending to the
488 client_make_packets_from_stdin_data(void)
492 /* Send buffered stdin data to the server. */
493 while (buffer_len(&stdin_buffer) > 0 &&
494 packet_not_very_much_data_to_write()) {
495 len = buffer_len(&stdin_buffer);
496 /* Keep the packets at reasonable size. */
497 if (len > packet_get_maxsize())
498 len = packet_get_maxsize();
499 packet_start(SSH_CMSG_STDIN_DATA);
500 packet_put_string(buffer_ptr(&stdin_buffer), len);
502 buffer_consume(&stdin_buffer, len);
503 /* If we have a pending EOF, send it now. */
504 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
505 packet_start(SSH_CMSG_EOF);
512 * Checks if the client window has changed, and sends a packet about it to
513 * the server if so. The actual change is detected elsewhere (by a software
514 * interrupt on Unix); this just checks the flag and sends a message if
519 client_check_window_change(void)
523 if (! received_window_change_signal)
526 received_window_change_signal = 0;
528 debug2("client_check_window_change: changed");
531 channel_send_window_changes();
533 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
535 packet_start(SSH_CMSG_WINDOW_SIZE);
536 packet_put_int((u_int)ws.ws_row);
537 packet_put_int((u_int)ws.ws_col);
538 packet_put_int((u_int)ws.ws_xpixel);
539 packet_put_int((u_int)ws.ws_ypixel);
545 client_global_request_reply(int type, u_int32_t seq, void *ctxt)
547 struct global_confirm *gc;
549 if ((gc = TAILQ_FIRST(&global_confirms)) == NULL)
552 gc->cb(type, seq, gc->ctx);
553 if (--gc->ref_count <= 0) {
554 TAILQ_REMOVE(&global_confirms, gc, entry);
555 bzero(gc, sizeof(*gc));
559 packet_set_alive_timeouts(0);
563 server_alive_check(void)
565 if (packet_inc_alive_timeouts() > options.server_alive_count_max) {
566 logit("Timeout, server %s not responding.", host);
569 packet_start(SSH2_MSG_GLOBAL_REQUEST);
570 packet_put_cstring("keepalive@openssh.com");
571 packet_put_char(1); /* boolean: want reply */
573 /* Insert an empty placeholder to maintain ordering */
574 client_register_global_confirm(NULL, NULL);
578 * Waits until the client can do something (some data becomes available on
579 * one of the file descriptors).
582 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
583 int *maxfdp, u_int *nallocp, int rekeying)
585 struct timeval tv, *tvp;
587 time_t minwait_secs = 0;
590 /* Add any selections by the channel mechanism. */
591 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp,
592 &minwait_secs, rekeying);
595 /* Read from the connection, unless our buffers are full. */
596 if (buffer_len(&stdout_buffer) < buffer_high &&
597 buffer_len(&stderr_buffer) < buffer_high &&
598 channel_not_very_much_buffered_data())
599 FD_SET(connection_in, *readsetp);
601 * Read from stdin, unless we have seen EOF or have very much
602 * buffered data to send to the server.
604 if (!stdin_eof && packet_not_very_much_data_to_write())
605 FD_SET(fileno(stdin), *readsetp);
607 /* Select stdout/stderr if have data in buffer. */
608 if (buffer_len(&stdout_buffer) > 0)
609 FD_SET(fileno(stdout), *writesetp);
610 if (buffer_len(&stderr_buffer) > 0)
611 FD_SET(fileno(stderr), *writesetp);
613 /* channel_prepare_select could have closed the last channel */
614 if (session_closed && !channel_still_open() &&
615 !packet_have_data_to_write()) {
616 /* clear mask since we did not call select() */
617 memset(*readsetp, 0, *nallocp);
618 memset(*writesetp, 0, *nallocp);
621 FD_SET(connection_in, *readsetp);
625 /* Select server connection if have data to write to the server. */
626 if (packet_have_data_to_write())
627 FD_SET(connection_out, *writesetp);
630 * Wait for something to happen. This will suspend the process until
631 * some selected descriptor can be read, written, or has some other
632 * event pending, or a timeout expires.
635 timeout_secs = INT_MAX; /* we use INT_MAX to mean no timeout */
636 if (options.server_alive_interval > 0 && compat20)
637 timeout_secs = options.server_alive_interval;
638 set_control_persist_exit_time();
639 if (control_persist_exit_time > 0) {
640 timeout_secs = MIN(timeout_secs,
641 control_persist_exit_time - time(NULL));
642 if (timeout_secs < 0)
645 if (minwait_secs != 0)
646 timeout_secs = MIN(timeout_secs, (int)minwait_secs);
647 if (timeout_secs == INT_MAX)
650 tv.tv_sec = timeout_secs;
655 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
660 * We have to clear the select masks, because we return.
661 * We have to return, because the mainloop checks for the flags
662 * set by the signal handlers.
664 memset(*readsetp, 0, *nallocp);
665 memset(*writesetp, 0, *nallocp);
669 /* Note: we might still have data in the buffers. */
670 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
671 buffer_append(&stderr_buffer, buf, strlen(buf));
674 server_alive_check();
678 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
680 /* Flush stdout and stderr buffers. */
681 if (buffer_len(bout) > 0)
682 atomicio(vwrite, fileno(stdout), buffer_ptr(bout),
684 if (buffer_len(berr) > 0)
685 atomicio(vwrite, fileno(stderr), buffer_ptr(berr),
688 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
691 * Free (and clear) the buffer to reduce the amount of data that gets
698 /* Send the suspend signal to the program itself. */
699 kill(getpid(), SIGTSTP);
701 /* Reset window sizes in case they have changed */
702 received_window_change_signal = 1;
704 /* OK, we have been continued by the user. Reinitialize buffers. */
709 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
713 client_process_net_input(fd_set *readset)
716 char buf[SSH_IOBUFSZ];
719 * Read input from the server, and add any such data to the buffer of
720 * the packet subsystem.
722 if (FD_ISSET(connection_in, readset)) {
723 /* Read as much as possible. */
724 len = roaming_read(connection_in, buf, sizeof(buf), &cont);
725 if (len == 0 && cont == 0) {
727 * Received EOF. The remote host has closed the
730 snprintf(buf, sizeof buf,
731 "Connection to %.300s closed by remote host.\r\n",
733 buffer_append(&stderr_buffer, buf, strlen(buf));
738 * There is a kernel bug on Solaris that causes select to
739 * sometimes wake up even though there is no data available.
742 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
747 * An error has encountered. Perhaps there is a
750 snprintf(buf, sizeof buf,
751 "Read from remote host %.300s: %.100s\r\n",
752 host, strerror(errno));
753 buffer_append(&stderr_buffer, buf, strlen(buf));
757 packet_process_incoming(buf, len);
762 client_status_confirm(int type, Channel *c, void *ctx)
764 struct channel_reply_ctx *cr = (struct channel_reply_ctx *)ctx;
769 * If a TTY was explicitly requested, then a failure to allocate
772 if (cr->action == CONFIRM_TTY &&
773 (options.request_tty == REQUEST_TTY_FORCE ||
774 options.request_tty == REQUEST_TTY_YES))
775 cr->action = CONFIRM_CLOSE;
777 /* XXX supress on mux _client_ quietmode */
778 tochan = options.log_level >= SYSLOG_LEVEL_ERROR &&
779 c->ctl_chan != -1 && c->extended_usage == CHAN_EXTENDED_WRITE;
781 if (type == SSH2_MSG_CHANNEL_SUCCESS) {
782 debug2("%s request accepted on channel %d",
783 cr->request_type, c->self);
784 } else if (type == SSH2_MSG_CHANNEL_FAILURE) {
786 snprintf(errmsg, sizeof(errmsg),
787 "%s request failed\r\n", cr->request_type);
789 snprintf(errmsg, sizeof(errmsg),
790 "%s request failed on channel %d",
791 cr->request_type, c->self);
793 /* If error occurred on primary session channel, then exit */
794 if (cr->action == CONFIRM_CLOSE && c->self == session_ident)
797 * If error occurred on mux client, append to
801 buffer_append(&c->extended, errmsg,
805 if (cr->action == CONFIRM_TTY) {
807 * If a TTY allocation error occurred, then arrange
808 * for the correct TTY to leave raw mode.
810 if (c->self == session_ident)
813 mux_tty_alloc_failed(c);
814 } else if (cr->action == CONFIRM_CLOSE) {
816 chan_write_failed(c);
823 client_abandon_status_confirm(Channel *c, void *ctx)
829 client_expect_confirm(int id, const char *request,
830 enum confirm_action action)
832 struct channel_reply_ctx *cr = xmalloc(sizeof(*cr));
834 cr->request_type = request;
837 channel_register_status_confirm(id, client_status_confirm,
838 client_abandon_status_confirm, cr);
842 client_register_global_confirm(global_confirm_cb *cb, void *ctx)
844 struct global_confirm *gc, *last_gc;
846 /* Coalesce identical callbacks */
847 last_gc = TAILQ_LAST(&global_confirms, global_confirms);
848 if (last_gc && last_gc->cb == cb && last_gc->ctx == ctx) {
849 if (++last_gc->ref_count >= INT_MAX)
850 fatal("%s: last_gc->ref_count = %d",
851 __func__, last_gc->ref_count);
855 gc = xmalloc(sizeof(*gc));
859 TAILQ_INSERT_TAIL(&global_confirms, gc, entry);
863 process_cmdline(void)
865 void (*handler)(int);
866 char *s, *cmd, *cancel_host;
867 int delete = 0, local = 0, remote = 0, dynamic = 0;
871 bzero(&fwd, sizeof(fwd));
872 fwd.listen_host = fwd.connect_host = NULL;
874 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
875 handler = signal(SIGINT, SIG_IGN);
876 cmd = s = read_passphrase("\r\nssh> ", RP_ECHO);
882 s++; /* Skip cmdline '-', if any */
886 if (*s == 'h' || *s == 'H' || *s == '?') {
888 logit(" -L[bind_address:]port:host:hostport "
889 "Request local forward");
890 logit(" -R[bind_address:]port:host:hostport "
891 "Request remote forward");
892 logit(" -D[bind_address:]port "
893 "Request dynamic forward");
894 logit(" -KL[bind_address:]port "
895 "Cancel local forward");
896 logit(" -KR[bind_address:]port "
897 "Cancel remote forward");
898 logit(" -KD[bind_address:]port "
899 "Cancel dynamic forward");
900 if (!options.permit_local_command)
903 "Execute local command");
907 if (*s == '!' && options.permit_local_command) {
924 logit("Invalid command.");
928 if (delete && !compat20) {
929 logit("Not supported for SSH protocol version 1.");
933 while (isspace(*++s))
936 /* XXX update list of forwards in options */
939 cancel_host = hpdelim(&s); /* may be NULL */
941 cancel_port = a2port(s);
942 cancel_host = cleanhostname(cancel_host);
944 cancel_port = a2port(cancel_host);
947 if (cancel_port <= 0) {
948 logit("Bad forwarding close port");
952 ok = channel_request_rforward_cancel(cancel_host,
955 ok = channel_cancel_lport_listener(cancel_host,
956 cancel_port, 0, options.gateway_ports) > 0;
958 ok = channel_cancel_lport_listener(cancel_host,
959 cancel_port, CHANNEL_CANCEL_PORT_STATIC,
960 options.gateway_ports) > 0;
962 logit("Unkown port forwarding.");
965 logit("Canceled forwarding.");
967 if (!parse_forward(&fwd, s, dynamic, remote)) {
968 logit("Bad forwarding specification.");
971 if (local || dynamic) {
972 if (channel_setup_local_fwd_listener(fwd.listen_host,
973 fwd.listen_port, fwd.connect_host,
974 fwd.connect_port, options.gateway_ports) < 0) {
975 logit("Port forwarding failed.");
979 if (channel_request_remote_forwarding(fwd.listen_host,
980 fwd.listen_port, fwd.connect_host,
981 fwd.connect_port) < 0) {
982 logit("Port forwarding failed.");
986 logit("Forwarding port.");
990 signal(SIGINT, handler);
991 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
994 if (fwd.listen_host != NULL)
995 xfree(fwd.listen_host);
996 if (fwd.connect_host != NULL)
997 xfree(fwd.connect_host);
1001 * Process the characters one by one, call with c==NULL for proto1 case.
1004 process_escapes(Channel *c, Buffer *bin, Buffer *bout, Buffer *berr,
1013 int *escape_pendingp, escape_char;
1014 struct escape_filter_ctx *efc;
1017 escape_pendingp = &escape_pending1;
1018 escape_char = escape_char1;
1020 if (c->filter_ctx == NULL)
1022 efc = (struct escape_filter_ctx *)c->filter_ctx;
1023 escape_pendingp = &efc->escape_pending;
1024 escape_char = efc->escape_char;
1030 for (i = 0; i < (u_int)len; i++) {
1031 /* Get one character at a time. */
1034 if (*escape_pendingp) {
1035 /* We have previously seen an escape character. */
1036 /* Clear the flag now. */
1037 *escape_pendingp = 0;
1039 /* Process the escaped character. */
1042 /* Terminate the connection. */
1043 snprintf(string, sizeof string, "%c.\r\n",
1045 buffer_append(berr, string, strlen(string));
1047 if (c && c->ctl_chan != -1) {
1048 chan_read_failed(c);
1049 chan_write_failed(c);
1056 /* XXX support this for mux clients */
1057 if (c && c->ctl_chan != -1) {
1059 snprintf(string, sizeof string,
1060 "%c%c escape not available to "
1061 "multiplexed sessions\r\n",
1063 buffer_append(berr, string,
1067 /* Suspend the program. Inform the user */
1068 snprintf(string, sizeof string,
1069 "%c^Z [suspend ssh]\r\n", escape_char);
1070 buffer_append(berr, string, strlen(string));
1072 /* Restore terminal modes and suspend. */
1073 client_suspend_self(bin, bout, berr);
1075 /* We have been continued. */
1080 snprintf(string, sizeof string,
1081 "%cB\r\n", escape_char);
1082 buffer_append(berr, string,
1084 channel_request_start(session_ident,
1086 packet_put_int(1000);
1093 if (datafellows & SSH_BUG_NOREKEY)
1094 logit("Server does not "
1095 "support re-keying");
1102 if (c && c->ctl_chan != -1)
1105 * Detach the program (continue to serve
1106 * connections, but put in background and no
1107 * more new connections).
1109 /* Restore tty modes. */
1111 options.request_tty == REQUEST_TTY_FORCE);
1113 /* Stop listening for new connections. */
1114 channel_stop_listening();
1116 snprintf(string, sizeof string,
1117 "%c& [backgrounded]\n", escape_char);
1118 buffer_append(berr, string, strlen(string));
1120 /* Fork into background. */
1123 error("fork: %.100s", strerror(errno));
1126 if (pid != 0) { /* This is the parent. */
1127 /* The parent just exits. */
1130 /* The child continues serving connections. */
1132 buffer_append(bin, "\004", 1);
1133 /* fake EOF on stdin */
1135 } else if (!stdin_eof) {
1137 * Sending SSH_CMSG_EOF alone does not
1138 * always appear to be enough. So we
1139 * try to send an EOF character first.
1141 packet_start(SSH_CMSG_STDIN_DATA);
1142 packet_put_string("\004", 1);
1146 if (buffer_len(bin) == 0) {
1147 packet_start(SSH_CMSG_EOF);
1154 if (c && c->ctl_chan != -1) {
1155 snprintf(string, sizeof string,
1157 Supported escape sequences:\r\n\
1158 %c. - terminate session\r\n\
1159 %cB - send a BREAK to the remote system\r\n\
1160 %cR - Request rekey (SSH protocol 2 only)\r\n\
1161 %c# - list forwarded connections\r\n\
1162 %c? - this message\r\n\
1163 %c%c - send the escape character by typing it twice\r\n\
1164 (Note that escapes are only recognized immediately after newline.)\r\n",
1165 escape_char, escape_char,
1166 escape_char, escape_char,
1167 escape_char, escape_char,
1168 escape_char, escape_char);
1170 snprintf(string, sizeof string,
1172 Supported escape sequences:\r\n\
1173 %c. - terminate connection (and any multiplexed sessions)\r\n\
1174 %cB - send a BREAK to the remote system\r\n\
1175 %cC - open a command line\r\n\
1176 %cR - Request rekey (SSH protocol 2 only)\r\n\
1177 %c^Z - suspend ssh\r\n\
1178 %c# - list forwarded connections\r\n\
1179 %c& - background ssh (when waiting for connections to terminate)\r\n\
1180 %c? - this message\r\n\
1181 %c%c - send the escape character by typing it twice\r\n\
1182 (Note that escapes are only recognized immediately after newline.)\r\n",
1183 escape_char, escape_char,
1184 escape_char, escape_char,
1185 escape_char, escape_char,
1186 escape_char, escape_char,
1187 escape_char, escape_char,
1190 buffer_append(berr, string, strlen(string));
1194 snprintf(string, sizeof string, "%c#\r\n",
1196 buffer_append(berr, string, strlen(string));
1197 s = channel_open_message();
1198 buffer_append(berr, s, strlen(s));
1203 if (c && c->ctl_chan != -1)
1209 if (ch != escape_char) {
1210 buffer_put_char(bin, escape_char);
1213 /* Escaped characters fall through here */
1218 * The previous character was not an escape char.
1219 * Check if this is an escape.
1221 if (last_was_cr && ch == escape_char) {
1223 * It is. Set the flag and continue to
1226 *escape_pendingp = 1;
1232 * Normal character. Record whether it was a newline,
1233 * and append it to the buffer.
1235 last_was_cr = (ch == '\r' || ch == '\n');
1236 buffer_put_char(bin, ch);
1243 client_process_input(fd_set *readset)
1246 char buf[SSH_IOBUFSZ];
1248 /* Read input from stdin. */
1249 if (FD_ISSET(fileno(stdin), readset)) {
1250 /* Read as much as possible. */
1251 len = read(fileno(stdin), buf, sizeof(buf));
1253 (errno == EAGAIN || errno == EINTR || errno == EWOULDBLOCK))
1254 return; /* we'll try again later */
1257 * Received EOF or error. They are treated
1258 * similarly, except that an error message is printed
1259 * if it was an error condition.
1262 snprintf(buf, sizeof buf, "read: %.100s\r\n",
1264 buffer_append(&stderr_buffer, buf, strlen(buf));
1266 /* Mark that we have seen EOF. */
1269 * Send an EOF message to the server unless there is
1270 * data in the buffer. If there is data in the
1271 * buffer, no message will be sent now. Code
1272 * elsewhere will send the EOF when the buffer
1273 * becomes empty if stdin_eof is set.
1275 if (buffer_len(&stdin_buffer) == 0) {
1276 packet_start(SSH_CMSG_EOF);
1279 } else if (escape_char1 == SSH_ESCAPECHAR_NONE) {
1281 * Normal successful read, and no escape character.
1282 * Just append the data to buffer.
1284 buffer_append(&stdin_buffer, buf, len);
1287 * Normal, successful read. But we have an escape
1288 * character and have to process the characters one
1291 if (process_escapes(NULL, &stdin_buffer,
1292 &stdout_buffer, &stderr_buffer, buf, len) == -1)
1299 client_process_output(fd_set *writeset)
1304 /* Write buffered output to stdout. */
1305 if (FD_ISSET(fileno(stdout), writeset)) {
1306 /* Write as much data as possible. */
1307 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
1308 buffer_len(&stdout_buffer));
1310 if (errno == EINTR || errno == EAGAIN ||
1311 errno == EWOULDBLOCK)
1315 * An error or EOF was encountered. Put an
1316 * error message to stderr buffer.
1318 snprintf(buf, sizeof buf,
1319 "write stdout: %.50s\r\n", strerror(errno));
1320 buffer_append(&stderr_buffer, buf, strlen(buf));
1325 /* Consume printed data from the buffer. */
1326 buffer_consume(&stdout_buffer, len);
1328 /* Write buffered output to stderr. */
1329 if (FD_ISSET(fileno(stderr), writeset)) {
1330 /* Write as much data as possible. */
1331 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
1332 buffer_len(&stderr_buffer));
1334 if (errno == EINTR || errno == EAGAIN ||
1335 errno == EWOULDBLOCK)
1339 * EOF or error, but can't even print
1346 /* Consume printed characters from the buffer. */
1347 buffer_consume(&stderr_buffer, len);
1352 * Get packets from the connection input buffer, and process them as long as
1353 * there are packets available.
1355 * Any unknown packets received during the actual
1356 * session cause the session to terminate. This is
1357 * intended to make debugging easier since no
1358 * confirmations are sent. Any compatible protocol
1359 * extensions must be negotiated during the
1360 * preparatory phase.
1364 client_process_buffered_input_packets(void)
1366 dispatch_run(DISPATCH_NONBLOCK, &quit_pending,
1367 compat20 ? xxx_kex : NULL);
1370 /* scan buf[] for '~' before sending data to the peer */
1372 /* Helper: allocate a new escape_filter_ctx and fill in its escape char */
1374 client_new_escape_filter_ctx(int escape_char)
1376 struct escape_filter_ctx *ret;
1378 ret = xmalloc(sizeof(*ret));
1379 ret->escape_pending = 0;
1380 ret->escape_char = escape_char;
1384 /* Free the escape filter context on channel free */
1386 client_filter_cleanup(int cid, void *ctx)
1392 client_simple_escape_filter(Channel *c, char *buf, int len)
1394 if (c->extended_usage != CHAN_EXTENDED_WRITE)
1397 return process_escapes(c, &c->input, &c->output, &c->extended,
1402 client_channel_closed(int id, void *arg)
1404 channel_cancel_cleanup(id);
1406 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1410 * Implements the interactive session with the server. This is called after
1411 * the user has been authenticated, and a command has been started on the
1412 * remote host. If escape_char != SSH_ESCAPECHAR_NONE, it is the character
1413 * used as an escape character for terminating or suspending the session.
1417 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
1419 fd_set *readset = NULL, *writeset = NULL;
1420 double start_time, total_time;
1421 int max_fd = 0, max_fd2 = 0, len, rekeying = 0;
1422 u_int64_t ibytes, obytes;
1426 debug("Entering interactive session.");
1428 start_time = get_current_time();
1430 /* Initialize variables. */
1431 escape_pending1 = 0;
1435 buffer_high = 64 * 1024;
1436 connection_in = packet_get_connection_in();
1437 connection_out = packet_get_connection_out();
1438 max_fd = MAX(connection_in, connection_out);
1441 /* enable nonblocking unless tty */
1442 if (!isatty(fileno(stdin)))
1443 set_nonblock(fileno(stdin));
1444 if (!isatty(fileno(stdout)))
1445 set_nonblock(fileno(stdout));
1446 if (!isatty(fileno(stderr)))
1447 set_nonblock(fileno(stderr));
1448 max_fd = MAX(max_fd, fileno(stdin));
1449 max_fd = MAX(max_fd, fileno(stdout));
1450 max_fd = MAX(max_fd, fileno(stderr));
1453 escape_char1 = escape_char_arg;
1455 /* Initialize buffers. */
1456 buffer_init(&stdin_buffer);
1457 buffer_init(&stdout_buffer);
1458 buffer_init(&stderr_buffer);
1460 client_init_dispatch();
1463 * Set signal handlers, (e.g. to restore non-blocking mode)
1464 * but don't overwrite SIG_IGN, matches behaviour from rsh(1)
1466 if (signal(SIGHUP, SIG_IGN) != SIG_IGN)
1467 signal(SIGHUP, signal_handler);
1468 if (signal(SIGINT, SIG_IGN) != SIG_IGN)
1469 signal(SIGINT, signal_handler);
1470 if (signal(SIGQUIT, SIG_IGN) != SIG_IGN)
1471 signal(SIGQUIT, signal_handler);
1472 if (signal(SIGTERM, SIG_IGN) != SIG_IGN)
1473 signal(SIGTERM, signal_handler);
1474 signal(SIGWINCH, window_change_handler);
1477 enter_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1480 session_ident = ssh2_chan_id;
1481 if (session_ident != -1) {
1482 if (escape_char_arg != SSH_ESCAPECHAR_NONE) {
1483 channel_register_filter(session_ident,
1484 client_simple_escape_filter, NULL,
1485 client_filter_cleanup,
1486 client_new_escape_filter_ctx(
1489 channel_register_cleanup(session_ident,
1490 client_channel_closed, 0);
1493 /* Check if we should immediately send eof on stdin. */
1494 client_check_initial_eof_on_stdin();
1497 /* Main loop of the client for the interactive session mode. */
1498 while (!quit_pending) {
1500 /* Process buffered packets sent by the server. */
1501 client_process_buffered_input_packets();
1503 if (compat20 && session_closed && !channel_still_open())
1506 rekeying = (xxx_kex != NULL && !xxx_kex->done);
1509 debug("rekeying in progress");
1512 * Make packets of buffered stdin data, and buffer
1513 * them for sending to the server.
1516 client_make_packets_from_stdin_data();
1519 * Make packets from buffered channel data, and
1520 * enqueue them for sending to the server.
1522 if (packet_not_very_much_data_to_write())
1523 channel_output_poll();
1526 * Check if the window size has changed, and buffer a
1527 * message about it to the server if so.
1529 client_check_window_change();
1535 * Wait until we have something to do (something becomes
1536 * available on one of the descriptors).
1539 client_wait_until_can_do_something(&readset, &writeset,
1540 &max_fd2, &nalloc, rekeying);
1545 /* Do channel operations unless rekeying in progress. */
1547 channel_after_select(readset, writeset);
1548 if (need_rekeying || packet_need_rekeying()) {
1549 debug("need rekeying");
1551 kex_send_kexinit(xxx_kex);
1556 /* Buffer input from the connection. */
1557 client_process_net_input(readset);
1563 /* Buffer data from stdin */
1564 client_process_input(readset);
1566 * Process output to stdout and stderr. Output to
1567 * the connection is processed elsewhere (above).
1569 client_process_output(writeset);
1572 if (session_resumed) {
1573 connection_in = packet_get_connection_in();
1574 connection_out = packet_get_connection_out();
1575 max_fd = MAX(max_fd, connection_out);
1576 max_fd = MAX(max_fd, connection_in);
1577 session_resumed = 0;
1581 * Send as much buffered packet data as possible to the
1584 if (FD_ISSET(connection_out, writeset))
1585 packet_write_poll();
1588 * If we are a backgrounded control master, and the
1589 * timeout has expired without any active client
1590 * connections, then quit.
1592 if (control_persist_exit_time > 0) {
1593 if (time(NULL) >= control_persist_exit_time) {
1594 debug("ControlPersist timeout expired");
1604 /* Terminate the session. */
1606 /* Stop watching for window change. */
1607 signal(SIGWINCH, SIG_DFL);
1610 packet_start(SSH2_MSG_DISCONNECT);
1611 packet_put_int(SSH2_DISCONNECT_BY_APPLICATION);
1612 packet_put_cstring("disconnected by user");
1613 packet_put_cstring(""); /* language tag */
1615 packet_write_wait();
1621 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
1623 /* restore blocking io */
1624 if (!isatty(fileno(stdin)))
1625 unset_nonblock(fileno(stdin));
1626 if (!isatty(fileno(stdout)))
1627 unset_nonblock(fileno(stdout));
1628 if (!isatty(fileno(stderr)))
1629 unset_nonblock(fileno(stderr));
1632 * If there was no shell or command requested, there will be no remote
1633 * exit status to be returned. In that case, clear error code if the
1634 * connection was deliberately terminated at this end.
1636 if (no_shell_flag && received_signal == SIGTERM) {
1637 received_signal = 0;
1641 if (received_signal)
1642 fatal("Killed by signal %d.", (int) received_signal);
1645 * In interactive mode (with pseudo tty) display a message indicating
1646 * that the connection has been closed.
1648 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
1649 snprintf(buf, sizeof buf,
1650 "Connection to %.64s closed.\r\n", host);
1651 buffer_append(&stderr_buffer, buf, strlen(buf));
1654 /* Output any buffered data for stdout. */
1655 if (buffer_len(&stdout_buffer) > 0) {
1656 len = atomicio(vwrite, fileno(stdout),
1657 buffer_ptr(&stdout_buffer), buffer_len(&stdout_buffer));
1658 if (len < 0 || (u_int)len != buffer_len(&stdout_buffer))
1659 error("Write failed flushing stdout buffer.");
1661 buffer_consume(&stdout_buffer, len);
1664 /* Output any buffered data for stderr. */
1665 if (buffer_len(&stderr_buffer) > 0) {
1666 len = atomicio(vwrite, fileno(stderr),
1667 buffer_ptr(&stderr_buffer), buffer_len(&stderr_buffer));
1668 if (len < 0 || (u_int)len != buffer_len(&stderr_buffer))
1669 error("Write failed flushing stderr buffer.");
1671 buffer_consume(&stderr_buffer, len);
1674 /* Clear and free any buffers. */
1675 memset(buf, 0, sizeof(buf));
1676 buffer_free(&stdin_buffer);
1677 buffer_free(&stdout_buffer);
1678 buffer_free(&stderr_buffer);
1680 /* Report bytes transferred, and transfer rates. */
1681 total_time = get_current_time() - start_time;
1682 packet_get_state(MODE_IN, NULL, NULL, NULL, &ibytes);
1683 packet_get_state(MODE_OUT, NULL, NULL, NULL, &obytes);
1684 verbose("Transferred: sent %llu, received %llu bytes, in %.1f seconds",
1685 (unsigned long long)obytes, (unsigned long long)ibytes, total_time);
1687 verbose("Bytes per second: sent %.1f, received %.1f",
1688 obytes / total_time, ibytes / total_time);
1689 /* Return the exit status of the program. */
1690 debug("Exit status %d", exit_status);
1697 client_input_stdout_data(int type, u_int32_t seq, void *ctxt)
1700 char *data = packet_get_string(&data_len);
1702 buffer_append(&stdout_buffer, data, data_len);
1703 memset(data, 0, data_len);
1707 client_input_stderr_data(int type, u_int32_t seq, void *ctxt)
1710 char *data = packet_get_string(&data_len);
1712 buffer_append(&stderr_buffer, data, data_len);
1713 memset(data, 0, data_len);
1717 client_input_exit_status(int type, u_int32_t seq, void *ctxt)
1719 exit_status = packet_get_int();
1721 /* Acknowledge the exit. */
1722 packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1725 * Must wait for packet to be sent since we are
1728 packet_write_wait();
1729 /* Flag that we want to exit. */
1733 client_input_agent_open(int type, u_int32_t seq, void *ctxt)
1736 int remote_id, sock;
1738 /* Read the remote channel number from the message. */
1739 remote_id = packet_get_int();
1743 * Get a connection to the local authentication agent (this may again
1746 sock = ssh_get_authentication_socket();
1749 * If we could not connect the agent, send an error message back to
1750 * the server. This should never happen unless the agent dies,
1751 * because authentication forwarding is only enabled if we have an
1755 c = channel_new("", SSH_CHANNEL_OPEN, sock, sock,
1756 -1, 0, 0, 0, "authentication agent connection", 1);
1757 c->remote_id = remote_id;
1761 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1762 packet_put_int(remote_id);
1764 /* Send a confirmation to the remote host. */
1765 debug("Forwarding authentication connection.");
1766 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1767 packet_put_int(remote_id);
1768 packet_put_int(c->self);
1774 client_request_forwarded_tcpip(const char *request_type, int rchan)
1777 char *listen_address, *originator_address;
1778 u_short listen_port, originator_port;
1780 /* Get rest of the packet */
1781 listen_address = packet_get_string(NULL);
1782 listen_port = packet_get_int();
1783 originator_address = packet_get_string(NULL);
1784 originator_port = packet_get_int();
1787 debug("client_request_forwarded_tcpip: listen %s port %d, "
1788 "originator %s port %d", listen_address, listen_port,
1789 originator_address, originator_port);
1791 c = channel_connect_by_listen_address(listen_port,
1792 "forwarded-tcpip", originator_address);
1794 xfree(originator_address);
1795 xfree(listen_address);
1800 client_request_x11(const char *request_type, int rchan)
1804 u_short originator_port;
1807 if (!options.forward_x11) {
1808 error("Warning: ssh server tried X11 forwarding.");
1809 error("Warning: this is probably a break-in attempt by a "
1810 "malicious server.");
1813 if (x11_refuse_time != 0 && time(NULL) >= x11_refuse_time) {
1814 verbose("Rejected X11 connection after ForwardX11Timeout "
1818 originator = packet_get_string(NULL);
1819 if (datafellows & SSH_BUG_X11FWD) {
1820 debug2("buggy server: x11 request w/o originator_port");
1821 originator_port = 0;
1823 originator_port = packet_get_int();
1826 /* XXX check permission */
1827 debug("client_request_x11: request from %s %d", originator,
1830 sock = x11_connect_display();
1833 if (options.hpn_disabled)
1834 c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1835 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
1838 c = channel_new("x11", SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1839 options.hpn_buffer_size, CHAN_X11_PACKET_DEFAULT,
1846 client_request_agent(const char *request_type, int rchan)
1851 if (!options.forward_agent) {
1852 error("Warning: ssh server tried agent forwarding.");
1853 error("Warning: this is probably a break-in attempt by a "
1854 "malicious server.");
1857 sock = ssh_get_authentication_socket();
1860 if (options.hpn_disabled)
1861 c = channel_new("authentication agent connection",
1862 SSH_CHANNEL_OPEN, sock, sock, -1,
1863 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1864 "authentication agent connection", 1);
1866 c = channel_new("authentication agent connection",
1867 SSH_CHANNEL_OPEN, sock, sock, -1,
1868 options.hpn_buffer_size, options.hpn_buffer_size, 0,
1869 "authentication agent connection", 1);
1875 client_request_tun_fwd(int tun_mode, int local_tun, int remote_tun)
1880 if (tun_mode == SSH_TUNMODE_NO)
1884 error("Tunnel forwarding is not supported for protocol 1");
1888 debug("Requesting tun unit %d in mode %d", local_tun, tun_mode);
1890 /* Open local tunnel device */
1891 if ((fd = tun_open(local_tun, tun_mode)) == -1) {
1892 error("Tunnel device open failed.");
1896 if (options.hpn_disabled)
1897 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1898 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1901 c = channel_new("tun", SSH_CHANNEL_OPENING, fd, fd, -1,
1902 options.hpn_buffer_size, CHAN_TCP_PACKET_DEFAULT,
1906 #if defined(SSH_TUN_FILTER)
1907 if (options.tun_open == SSH_TUNMODE_POINTOPOINT)
1908 channel_register_filter(c->self, sys_tun_infilter,
1909 sys_tun_outfilter, NULL, NULL);
1912 packet_start(SSH2_MSG_CHANNEL_OPEN);
1913 packet_put_cstring("tun@openssh.com");
1914 packet_put_int(c->self);
1915 packet_put_int(c->local_window_max);
1916 packet_put_int(c->local_maxpacket);
1917 packet_put_int(tun_mode);
1918 packet_put_int(remote_tun);
1924 /* XXXX move to generic input handler */
1926 client_input_channel_open(int type, u_int32_t seq, void *ctxt)
1931 u_int rmaxpack, rwindow, len;
1933 ctype = packet_get_string(&len);
1934 rchan = packet_get_int();
1935 rwindow = packet_get_int();
1936 rmaxpack = packet_get_int();
1938 debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1939 ctype, rchan, rwindow, rmaxpack);
1941 if (strcmp(ctype, "forwarded-tcpip") == 0) {
1942 c = client_request_forwarded_tcpip(ctype, rchan);
1943 } else if (strcmp(ctype, "x11") == 0) {
1944 c = client_request_x11(ctype, rchan);
1945 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1946 c = client_request_agent(ctype, rchan);
1948 /* XXX duplicate : */
1950 debug("confirm %s", ctype);
1951 c->remote_id = rchan;
1952 c->remote_window = rwindow;
1953 c->remote_maxpacket = rmaxpack;
1954 if (c->type != SSH_CHANNEL_CONNECTING) {
1955 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1956 packet_put_int(c->remote_id);
1957 packet_put_int(c->self);
1958 packet_put_int(c->local_window);
1959 packet_put_int(c->local_maxpacket);
1963 debug("failure %s", ctype);
1964 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1965 packet_put_int(rchan);
1966 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1967 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
1968 packet_put_cstring("open failed");
1969 packet_put_cstring("");
1976 client_input_channel_req(int type, u_int32_t seq, void *ctxt)
1979 int exitval, id, reply, success = 0;
1982 id = packet_get_int();
1983 rtype = packet_get_string(NULL);
1984 reply = packet_get_char();
1986 debug("client_input_channel_req: channel %d rtype %s reply %d",
1990 error("client_input_channel_req: request for channel -1");
1991 } else if ((c = channel_lookup(id)) == NULL) {
1992 error("client_input_channel_req: channel %d: "
1993 "unknown channel", id);
1994 } else if (strcmp(rtype, "eow@openssh.com") == 0) {
1997 } else if (strcmp(rtype, "exit-status") == 0) {
1998 exitval = packet_get_int();
1999 if (c->ctl_chan != -1) {
2000 mux_exit_message(c, exitval);
2002 } else if (id == session_ident) {
2003 /* Record exit value of local session */
2005 exit_status = exitval;
2007 /* Probably for a mux channel that has already closed */
2008 debug("%s: no sink for exit-status on channel %d",
2013 if (reply && c != NULL) {
2014 packet_start(success ?
2015 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
2016 packet_put_int(c->remote_id);
2022 client_input_global_request(int type, u_int32_t seq, void *ctxt)
2028 rtype = packet_get_string(NULL);
2029 want_reply = packet_get_char();
2030 debug("client_input_global_request: rtype %s want_reply %d",
2033 packet_start(success ?
2034 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
2036 packet_write_wait();
2042 client_session2_setup(int id, int want_tty, int want_subsystem,
2043 const char *term, struct termios *tiop, int in_fd, Buffer *cmd, char **env)
2048 debug2("%s: id %d", __func__, id);
2050 if ((c = channel_lookup(id)) == NULL)
2051 fatal("client_session2_setup: channel %d: unknown channel", id);
2053 packet_set_interactive(want_tty,
2054 options.ip_qos_interactive, options.ip_qos_bulk);
2059 /* Store window size in the packet. */
2060 if (ioctl(in_fd, TIOCGWINSZ, &ws) < 0)
2061 memset(&ws, 0, sizeof(ws));
2063 channel_request_start(id, "pty-req", 1);
2064 client_expect_confirm(id, "PTY allocation", CONFIRM_TTY);
2065 packet_put_cstring(term != NULL ? term : "");
2066 packet_put_int((u_int)ws.ws_col);
2067 packet_put_int((u_int)ws.ws_row);
2068 packet_put_int((u_int)ws.ws_xpixel);
2069 packet_put_int((u_int)ws.ws_ypixel);
2071 tiop = get_saved_tio();
2072 tty_make_modes(-1, tiop);
2074 /* XXX wait for reply */
2078 /* Transfer any environment variables from client to server */
2079 if (options.num_send_env != 0 && env != NULL) {
2083 debug("Sending environment.");
2084 for (i = 0; env[i] != NULL; i++) {
2086 name = xstrdup(env[i]);
2087 if ((val = strchr(name, '=')) == NULL) {
2094 for (j = 0; j < options.num_send_env; j++) {
2095 if (match_pattern(name, options.send_env[j])) {
2101 debug3("Ignored env %s", name);
2106 debug("Sending env %s = %s", name, val);
2107 channel_request_start(id, "env", 0);
2108 packet_put_cstring(name);
2109 packet_put_cstring(val);
2115 len = buffer_len(cmd);
2119 if (want_subsystem) {
2120 debug("Sending subsystem: %.*s",
2121 len, (u_char*)buffer_ptr(cmd));
2122 channel_request_start(id, "subsystem", 1);
2123 client_expect_confirm(id, "subsystem", CONFIRM_CLOSE);
2125 debug("Sending command: %.*s",
2126 len, (u_char*)buffer_ptr(cmd));
2127 channel_request_start(id, "exec", 1);
2128 client_expect_confirm(id, "exec", CONFIRM_CLOSE);
2130 packet_put_string(buffer_ptr(cmd), buffer_len(cmd));
2133 channel_request_start(id, "shell", 1);
2134 client_expect_confirm(id, "shell", CONFIRM_CLOSE);
2140 client_init_dispatch_20(void)
2142 dispatch_init(&dispatch_protocol_error);
2144 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
2145 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
2146 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
2147 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
2148 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
2149 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2150 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2151 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
2152 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
2153 dispatch_set(SSH2_MSG_CHANNEL_SUCCESS, &channel_input_status_confirm);
2154 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &channel_input_status_confirm);
2155 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &client_input_global_request);
2158 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
2160 /* global request reply messages */
2161 dispatch_set(SSH2_MSG_REQUEST_FAILURE, &client_global_request_reply);
2162 dispatch_set(SSH2_MSG_REQUEST_SUCCESS, &client_global_request_reply);
2166 client_init_dispatch_13(void)
2168 dispatch_init(NULL);
2169 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
2170 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
2171 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
2172 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
2173 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
2174 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
2175 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
2176 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
2177 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
2179 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
2180 &client_input_agent_open : &deny_input_open);
2181 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
2182 &x11_input_open : &deny_input_open);
2186 client_init_dispatch_15(void)
2188 client_init_dispatch_13();
2189 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
2190 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
2194 client_init_dispatch(void)
2197 client_init_dispatch_20();
2199 client_init_dispatch_13();
2201 client_init_dispatch_15();
2205 client_stop_mux(void)
2207 if (options.control_path != NULL && muxserver_sock != -1)
2208 unlink(options.control_path);
2210 * If we are in persist mode, signal that we should close when all
2211 * active channels are closed.
2213 if (options.control_persist) {
2215 setproctitle("[stopped mux]");
2219 /* client specific fatal cleanup */
2223 leave_raw_mode(options.request_tty == REQUEST_TTY_FORCE);
2224 leave_non_blocking();
2225 if (options.control_path != NULL && muxserver_sock != -1)
2226 unlink(options.control_path);
2227 ssh_kill_proxy_command();