2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * The main loop for the interactive session (client side).
7 * As far as I am concerned, the code I have written for this software
8 * can be used freely for any purpose. Any derived versions of this
9 * software must be clearly marked as such, and if the derived work is
10 * incompatible with the protocol description in the RFC file, it must be
11 * called by a name other than "ssh" or "Secure Shell".
14 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
37 * SSH2 support added by Markus Friedl.
38 * Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
40 * Redistribution and use in source and binary forms, with or without
41 * modification, are permitted provided that the following conditions
43 * 1. Redistributions of source code must retain the above copyright
44 * notice, this list of conditions and the following disclaimer.
45 * 2. Redistributions in binary form must reproduce the above copyright
46 * notice, this list of conditions and the following disclaimer in the
47 * documentation and/or other materials provided with the distribution.
49 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
50 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
51 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
52 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
53 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
54 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
55 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
56 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
57 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
58 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
62 RCSID("$OpenBSD: clientloop.c,v 1.49 2001/02/08 19:30:51 itojun Exp $");
78 #include "clientloop.h"
83 extern Options options;
85 /* Flag indicating that stdin should be redirected from /dev/null. */
86 extern int stdin_null_flag;
89 * Name of the host we are connecting to. This is the name given on the
90 * command line, or the HostName specified for the user-supplied name in a
96 * Flag to indicate that we have received a window change signal which has
97 * not yet been processed. This will cause a message indicating the new
98 * window size to be sent to the server a little later. This is volatile
99 * because this is updated in a signal handler.
101 static volatile int received_window_change_signal = 0;
103 /* Terminal modes, as saved by enter_raw_mode. */
104 static struct termios saved_tio;
107 * Flag indicating whether we are in raw mode. This is used by
108 * enter_raw_mode and leave_raw_mode.
110 static int in_raw_mode = 0;
112 /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
113 static int in_non_blocking_mode = 0;
115 /* Common data for the client loop code. */
116 static int quit_pending; /* Set to non-zero to quit the client loop. */
117 static int escape_char; /* Escape character. */
118 static int escape_pending; /* Last character was the escape character */
119 static int last_was_cr; /* Last character was a newline. */
120 static int exit_status; /* Used to store the exit status of the command. */
121 static int stdin_eof; /* EOF has been encountered on standard error. */
122 static Buffer stdin_buffer; /* Buffer for stdin data. */
123 static Buffer stdout_buffer; /* Buffer for stdout data. */
124 static Buffer stderr_buffer; /* Buffer for stderr data. */
125 static u_long stdin_bytes, stdout_bytes, stderr_bytes;
126 static u_int buffer_high;/* Soft max buffer size. */
127 static int connection_in; /* Connection to server (input). */
128 static int connection_out; /* Connection to server (output). */
130 void client_init_dispatch(void);
131 int session_ident = -1;
133 /* Returns the user\'s terminal to normal mode if it had been put in raw mode. */
141 if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0)
144 fatal_remove_cleanup((void (*) (void *)) leave_raw_mode, NULL);
147 /* Puts the user\'s terminal in raw mode. */
154 if (tcgetattr(fileno(stdin), &tio) < 0)
157 tio.c_iflag |= IGNPAR;
158 tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
159 tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
161 tio.c_lflag &= ~IEXTEN;
163 tio.c_oflag &= ~OPOST;
166 if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0)
170 fatal_add_cleanup((void (*) (void *)) leave_raw_mode, NULL);
173 /* Restores stdin to blocking mode. */
176 leave_non_blocking(void)
178 if (in_non_blocking_mode) {
179 (void) fcntl(fileno(stdin), F_SETFL, 0);
180 in_non_blocking_mode = 0;
181 fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
185 /* Puts stdin terminal in non-blocking mode. */
188 enter_non_blocking(void)
190 in_non_blocking_mode = 1;
191 (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
192 fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
196 * Signal handler for the window change signal (SIGWINCH). This just sets a
197 * flag indicating that the window has changed.
201 window_change_handler(int sig)
203 received_window_change_signal = 1;
204 signal(SIGWINCH, window_change_handler);
208 * Signal handler for signals that cause the program to terminate. These
209 * signals must be trapped to restore terminal modes.
213 signal_handler(int sig)
217 if (in_non_blocking_mode)
218 leave_non_blocking();
219 channel_stop_listening();
221 fatal("Killed by signal %d.", sig);
225 * Returns current time in seconds from Jan 1, 1970 with the maximum
226 * available resolution.
230 get_current_time(void)
233 gettimeofday(&tv, NULL);
234 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
238 * This is called when the interactive is entered. This checks if there is
239 * an EOF coming on stdin. We must check this explicitly, as select() does
240 * not appear to wake up when redirecting from /dev/null.
244 client_check_initial_eof_on_stdin(void)
250 * If standard input is to be "redirected from /dev/null", we simply
251 * mark that we have seen an EOF and send an EOF message to the
252 * server. Otherwise, we try to read a single character; it appears
253 * that for some files, such /dev/null, select() never wakes up for
254 * read for this descriptor, which means that we never get EOF. This
255 * way we will get the EOF if stdin comes from /dev/null or similar.
257 if (stdin_null_flag) {
258 /* Fake EOF on stdin. */
259 debug("Sending eof.");
261 packet_start(SSH_CMSG_EOF);
264 enter_non_blocking();
266 /* Check for immediate EOF on stdin. */
267 len = read(fileno(stdin), buf, 1);
269 /* EOF. Record that we have seen it and send EOF to server. */
270 debug("Sending eof.");
272 packet_start(SSH_CMSG_EOF);
274 } else if (len > 0) {
276 * Got data. We must store the data in the buffer,
277 * and also process it as an escape character if
280 if ((u_char) buf[0] == escape_char)
283 buffer_append(&stdin_buffer, buf, 1);
287 leave_non_blocking();
293 * Make packets from buffered stdin data, and buffer them for sending to the
298 client_make_packets_from_stdin_data(void)
302 /* Send buffered stdin data to the server. */
303 while (buffer_len(&stdin_buffer) > 0 &&
304 packet_not_very_much_data_to_write()) {
305 len = buffer_len(&stdin_buffer);
306 /* Keep the packets at reasonable size. */
307 if (len > packet_get_maxsize())
308 len = packet_get_maxsize();
309 packet_start(SSH_CMSG_STDIN_DATA);
310 packet_put_string(buffer_ptr(&stdin_buffer), len);
312 buffer_consume(&stdin_buffer, len);
313 /* If we have a pending EOF, send it now. */
314 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
315 packet_start(SSH_CMSG_EOF);
322 * Checks if the client window has changed, and sends a packet about it to
323 * the server if so. The actual change is detected elsewhere (by a software
324 * interrupt on Unix); this just checks the flag and sends a message if
329 client_check_window_change(void)
333 if (! received_window_change_signal)
336 received_window_change_signal = 0;
338 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
341 debug2("client_check_window_change: changed");
344 channel_request_start(session_ident, "window-change", 0);
345 packet_put_int(ws.ws_col);
346 packet_put_int(ws.ws_row);
347 packet_put_int(ws.ws_xpixel);
348 packet_put_int(ws.ws_ypixel);
351 packet_start(SSH_CMSG_WINDOW_SIZE);
352 packet_put_int(ws.ws_row);
353 packet_put_int(ws.ws_col);
354 packet_put_int(ws.ws_xpixel);
355 packet_put_int(ws.ws_ypixel);
361 * Waits until the client can do something (some data becomes available on
362 * one of the file descriptors).
366 client_wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp,
369 /* Add any selections by the channel mechanism. */
370 channel_prepare_select(readsetp, writesetp, maxfdp);
373 /* Read from the connection, unless our buffers are full. */
374 if (buffer_len(&stdout_buffer) < buffer_high &&
375 buffer_len(&stderr_buffer) < buffer_high &&
376 channel_not_very_much_buffered_data())
377 FD_SET(connection_in, *readsetp);
379 * Read from stdin, unless we have seen EOF or have very much
380 * buffered data to send to the server.
382 if (!stdin_eof && packet_not_very_much_data_to_write())
383 FD_SET(fileno(stdin), *readsetp);
385 /* Select stdout/stderr if have data in buffer. */
386 if (buffer_len(&stdout_buffer) > 0)
387 FD_SET(fileno(stdout), *writesetp);
388 if (buffer_len(&stderr_buffer) > 0)
389 FD_SET(fileno(stderr), *writesetp);
391 FD_SET(connection_in, *readsetp);
394 /* Select server connection if have data to write to the server. */
395 if (packet_have_data_to_write())
396 FD_SET(connection_out, *writesetp);
399 * Wait for something to happen. This will suspend the process until
400 * some selected descriptor can be read, written, or has some other
401 * event pending. Note: if you want to implement SSH_MSG_IGNORE
402 * messages to fool traffic analysis, this might be the place to do
403 * it: just have a random timeout for the select, and send a random
404 * SSH_MSG_IGNORE packet when the timeout expires.
407 if (select((*maxfdp)+1, *readsetp, *writesetp, NULL, NULL) < 0) {
411 /* Note: we might still have data in the buffers. */
412 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
413 buffer_append(&stderr_buffer, buf, strlen(buf));
414 stderr_bytes += strlen(buf);
420 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
422 struct winsize oldws, newws;
424 /* Flush stdout and stderr buffers. */
425 if (buffer_len(bout) > 0)
426 atomicio(write, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
427 if (buffer_len(berr) > 0)
428 atomicio(write, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
433 * Free (and clear) the buffer to reduce the amount of data that gets
440 /* Save old window size. */
441 ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
443 /* Send the suspend signal to the program itself. */
444 kill(getpid(), SIGTSTP);
446 /* Check if the window size has changed. */
447 if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
448 (oldws.ws_row != newws.ws_row ||
449 oldws.ws_col != newws.ws_col ||
450 oldws.ws_xpixel != newws.ws_xpixel ||
451 oldws.ws_ypixel != newws.ws_ypixel))
452 received_window_change_signal = 1;
454 /* OK, we have been continued by the user. Reinitialize buffers. */
463 client_process_net_input(fd_set * readset)
469 * Read input from the server, and add any such data to the buffer of
470 * the packet subsystem.
472 if (FD_ISSET(connection_in, readset)) {
473 /* Read as much as possible. */
474 len = read(connection_in, buf, sizeof(buf));
476 /* Received EOF. The remote host has closed the connection. */
477 snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
479 buffer_append(&stderr_buffer, buf, strlen(buf));
480 stderr_bytes += strlen(buf);
485 * There is a kernel bug on Solaris that causes select to
486 * sometimes wake up even though there is no data available.
488 if (len < 0 && errno == EAGAIN)
492 /* An error has encountered. Perhaps there is a network problem. */
493 snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
494 host, strerror(errno));
495 buffer_append(&stderr_buffer, buf, strlen(buf));
496 stderr_bytes += strlen(buf);
500 packet_process_incoming(buf, len);
504 /* process the characters one by one */
506 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
515 for (i = 0; i < len; i++) {
516 /* Get one character at a time. */
519 if (escape_pending) {
520 /* We have previously seen an escape character. */
521 /* Clear the flag now. */
524 /* Process the escaped character. */
527 /* Terminate the connection. */
528 snprintf(string, sizeof string, "%c.\r\n", escape_char);
529 buffer_append(berr, string, strlen(string));
530 /*stderr_bytes += strlen(string); XXX*/
536 /* Suspend the program. */
537 /* Print a message to that effect to the user. */
538 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
539 buffer_append(berr, string, strlen(string));
540 /*stderr_bytes += strlen(string); XXX*/
542 /* Restore terminal modes and suspend. */
543 client_suspend_self(bin, bout, berr);
545 /* We have been continued. */
549 /* XXX does not work yet with proto 2 */
553 * Detach the program (continue to serve connections,
554 * but put in background and no more new connections).
558 * Sending SSH_CMSG_EOF alone does not always appear
559 * to be enough. So we try to send an EOF character
562 packet_start(SSH_CMSG_STDIN_DATA);
563 packet_put_string("\004", 1);
567 if (buffer_len(bin) == 0) {
568 packet_start(SSH_CMSG_EOF);
572 /* Restore tty modes. */
575 /* Stop listening for new connections. */
576 channel_stop_listening();
578 printf("%c& [backgrounded]\n", escape_char);
580 /* Fork into background. */
583 error("fork: %.100s", strerror(errno));
586 if (pid != 0) { /* This is the parent. */
587 /* The parent just exits. */
590 /* The child continues serving connections. */
594 snprintf(string, sizeof string,
596 Supported escape sequences:\r\n\
597 ~. - terminate connection\r\n\
598 ~^Z - suspend ssh\r\n\
599 ~# - list forwarded connections\r\n\
600 ~& - background ssh (when waiting for connections to terminate)\r\n\
601 ~? - this message\r\n\
602 ~~ - send the escape character by typing it twice\r\n\
603 (Note that escapes are only recognized immediately after newline.)\r\n",
605 buffer_append(berr, string, strlen(string));
609 snprintf(string, sizeof string, "%c#\r\n", escape_char);
610 buffer_append(berr, string, strlen(string));
611 s = channel_open_message();
612 buffer_append(berr, s, strlen(s));
617 if (ch != escape_char) {
618 buffer_put_char(bin, escape_char);
621 /* Escaped characters fall through here */
626 * The previous character was not an escape char. Check if this
629 if (last_was_cr && ch == escape_char) {
630 /* It is. Set the flag and continue to next character. */
637 * Normal character. Record whether it was a newline,
638 * and append it to the buffer.
640 last_was_cr = (ch == '\r' || ch == '\n');
641 buffer_put_char(bin, ch);
648 client_process_input(fd_set * readset)
654 /* Read input from stdin. */
655 if (FD_ISSET(fileno(stdin), readset)) {
656 /* Read as much as possible. */
657 len = read(fileno(stdin), buf, sizeof(buf));
660 * Received EOF or error. They are treated
661 * similarly, except that an error message is printed
662 * if it was an error condition.
665 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
666 buffer_append(&stderr_buffer, buf, strlen(buf));
667 stderr_bytes += strlen(buf);
669 /* Mark that we have seen EOF. */
672 * Send an EOF message to the server unless there is
673 * data in the buffer. If there is data in the
674 * buffer, no message will be sent now. Code
675 * elsewhere will send the EOF when the buffer
676 * becomes empty if stdin_eof is set.
678 if (buffer_len(&stdin_buffer) == 0) {
679 packet_start(SSH_CMSG_EOF);
682 } else if (escape_char == -1) {
684 * Normal successful read, and no escape character.
685 * Just append the data to buffer.
687 buffer_append(&stdin_buffer, buf, len);
691 * Normal, successful read. But we have an escape character
692 * and have to process the characters one by one.
694 ret = process_escapes(&stdin_buffer, &stdout_buffer, &stderr_buffer, buf, len);
703 client_process_output(fd_set * writeset)
708 /* Write buffered output to stdout. */
709 if (FD_ISSET(fileno(stdout), writeset)) {
710 /* Write as much data as possible. */
711 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
712 buffer_len(&stdout_buffer));
718 * An error or EOF was encountered. Put an
719 * error message to stderr buffer.
721 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
722 buffer_append(&stderr_buffer, buf, strlen(buf));
723 stderr_bytes += strlen(buf);
728 /* Consume printed data from the buffer. */
729 buffer_consume(&stdout_buffer, len);
731 /* Write buffered output to stderr. */
732 if (FD_ISSET(fileno(stderr), writeset)) {
733 /* Write as much data as possible. */
734 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
735 buffer_len(&stderr_buffer));
740 /* EOF or error, but can't even print error message. */
745 /* Consume printed characters from the buffer. */
746 buffer_consume(&stderr_buffer, len);
751 * Get packets from the connection input buffer, and process them as long as
752 * there are packets available.
754 * Any unknown packets received during the actual
755 * session cause the session to terminate. This is
756 * intended to make debugging easier since no
757 * confirmations are sent. Any compatible protocol
758 * extensions must be negotiated during the
763 client_process_buffered_input_packets(void)
765 dispatch_run(DISPATCH_NONBLOCK, &quit_pending, NULL);
768 /* scan buf[] for '~' before sending data to the peer */
771 simple_escape_filter(Channel *c, char *buf, int len)
773 /* XXX we assume c->extended is writeable */
774 return process_escapes(&c->input, &c->output, &c->extended, buf, len);
778 * Implements the interactive session with the server. This is called after
779 * the user has been authenticated, and a command has been started on the
780 * remote host. If escape_char != -1, it is the character used as an escape
781 * character for terminating or suspending the session.
785 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
787 fd_set *readset = NULL, *writeset = NULL;
789 double start_time, total_time;
793 debug("Entering interactive session.");
795 start_time = get_current_time();
797 /* Initialize variables. */
802 buffer_high = 64 * 1024;
803 connection_in = packet_get_connection_in();
804 connection_out = packet_get_connection_out();
805 max_fd = MAX(connection_in, connection_out);
808 max_fd = MAX(max_fd, fileno(stdin));
809 max_fd = MAX(max_fd, fileno(stdout));
810 max_fd = MAX(max_fd, fileno(stderr));
816 escape_char = escape_char_arg;
818 /* Initialize buffers. */
819 buffer_init(&stdin_buffer);
820 buffer_init(&stdout_buffer);
821 buffer_init(&stderr_buffer);
823 client_init_dispatch();
825 /* Set signal handlers to restore non-blocking mode. */
826 signal(SIGINT, signal_handler);
827 signal(SIGQUIT, signal_handler);
828 signal(SIGTERM, signal_handler);
829 signal(SIGPIPE, SIG_IGN);
831 signal(SIGWINCH, window_change_handler);
837 session_ident = ssh2_chan_id;
838 if (escape_char != -1)
839 channel_register_filter(session_ident,
840 simple_escape_filter);
842 /* Check if we should immediately send eof on stdin. */
843 client_check_initial_eof_on_stdin();
846 /* Main loop of the client for the interactive session mode. */
847 while (!quit_pending) {
849 /* Process buffered packets sent by the server. */
850 client_process_buffered_input_packets();
852 if (compat20 && !channel_still_open()) {
853 debug2("!channel_still_open.");
858 * Make packets of buffered stdin data, and buffer them for
859 * sending to the server.
862 client_make_packets_from_stdin_data();
865 * Make packets from buffered channel data, and enqueue them
866 * for sending to the server.
868 if (packet_not_very_much_data_to_write())
869 channel_output_poll();
872 * Check if the window size has changed, and buffer a message
873 * about it to the server if so.
875 client_check_window_change();
881 * Wait until we have something to do (something becomes
882 * available on one of the descriptors).
884 client_wait_until_can_do_something(&readset, &writeset, &max_fd);
889 /* Do channel operations. */
890 channel_after_select(readset, writeset);
892 /* Buffer input from the connection. */
893 client_process_net_input(readset);
899 /* Buffer data from stdin */
900 client_process_input(readset);
902 * Process output to stdout and stderr. Output to
903 * the connection is processed elsewhere (above).
905 client_process_output(writeset);
908 /* Send as much buffered packet data as possible to the sender. */
909 if (FD_ISSET(connection_out, writeset))
917 /* Terminate the session. */
919 /* Stop watching for window change. */
921 signal(SIGWINCH, SIG_DFL);
923 /* Stop listening for connections. */
924 channel_stop_listening();
927 * In interactive mode (with pseudo tty) display a message indicating
928 * that the connection has been closed.
930 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
931 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
932 buffer_append(&stderr_buffer, buf, strlen(buf));
933 stderr_bytes += strlen(buf);
935 /* Output any buffered data for stdout. */
936 while (buffer_len(&stdout_buffer) > 0) {
937 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
938 buffer_len(&stdout_buffer));
940 error("Write failed flushing stdout buffer.");
943 buffer_consume(&stdout_buffer, len);
946 /* Output any buffered data for stderr. */
947 while (buffer_len(&stderr_buffer) > 0) {
948 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
949 buffer_len(&stderr_buffer));
951 error("Write failed flushing stderr buffer.");
954 buffer_consume(&stderr_buffer, len);
960 /* Clear and free any buffers. */
961 memset(buf, 0, sizeof(buf));
962 buffer_free(&stdin_buffer);
963 buffer_free(&stdout_buffer);
964 buffer_free(&stderr_buffer);
966 /* Report bytes transferred, and transfer rates. */
967 total_time = get_current_time() - start_time;
968 debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
969 stdin_bytes, stdout_bytes, stderr_bytes, total_time);
971 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
972 stdin_bytes / total_time, stdout_bytes / total_time,
973 stderr_bytes / total_time);
975 /* Return the exit status of the program. */
976 debug("Exit status %d", exit_status);
983 client_input_stdout_data(int type, int plen, void *ctxt)
986 char *data = packet_get_string(&data_len);
987 packet_integrity_check(plen, 4 + data_len, type);
988 buffer_append(&stdout_buffer, data, data_len);
989 stdout_bytes += data_len;
990 memset(data, 0, data_len);
994 client_input_stderr_data(int type, int plen, void *ctxt)
997 char *data = packet_get_string(&data_len);
998 packet_integrity_check(plen, 4 + data_len, type);
999 buffer_append(&stderr_buffer, data, data_len);
1000 stdout_bytes += data_len;
1001 memset(data, 0, data_len);
1005 client_input_exit_status(int type, int plen, void *ctxt)
1007 packet_integrity_check(plen, 4, type);
1008 exit_status = packet_get_int();
1009 /* Acknowledge the exit. */
1010 packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1013 * Must wait for packet to be sent since we are
1016 packet_write_wait();
1017 /* Flag that we want to exit. */
1022 client_request_forwarded_tcpip(const char *request_type, int rchan)
1025 char *listen_address, *originator_address;
1026 int listen_port, originator_port;
1029 /* Get rest of the packet */
1030 listen_address = packet_get_string(NULL);
1031 listen_port = packet_get_int();
1032 originator_address = packet_get_string(NULL);
1033 originator_port = packet_get_int();
1036 debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1037 listen_address, listen_port, originator_address, originator_port);
1039 sock = channel_connect_by_listen_adress(listen_port);
1041 newch = channel_new("forwarded-tcpip",
1042 SSH_CHANNEL_CONNECTING, sock, sock, -1,
1043 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1044 xstrdup(originator_address), 1);
1045 c = channel_lookup(newch);
1047 xfree(originator_address);
1048 xfree(listen_address);
1053 client_request_x11(const char *request_type, int rchan)
1057 int originator_port;
1060 if (!options.forward_x11) {
1061 error("Warning: ssh server tried X11 forwarding.");
1062 error("Warning: this is probably a break in attempt by a malicious server.");
1065 originator = packet_get_string(NULL);
1066 if (datafellows & SSH_BUG_X11FWD) {
1067 debug2("buggy server: x11 request w/o originator_port");
1068 originator_port = 0;
1070 originator_port = packet_get_int();
1073 /* XXX check permission */
1074 debug("client_request_x11: request from %s %d", originator,
1076 sock = x11_connect_display();
1078 newch = channel_new("x11",
1079 SSH_CHANNEL_X11_OPEN, sock, sock, -1,
1080 CHAN_TCP_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT, 0,
1082 c = channel_lookup(newch);
1089 client_request_agent(const char *request_type, int rchan)
1094 if (!options.forward_agent) {
1095 error("Warning: ssh server tried agent forwarding.");
1096 error("Warning: this is probably a break in attempt by a malicious server.");
1099 sock = ssh_get_authentication_socket();
1101 newch = channel_new("authentication agent connection",
1102 SSH_CHANNEL_OPEN, sock, sock, -1,
1103 CHAN_X11_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1104 xstrdup("authentication agent connection"), 1);
1105 c = channel_lookup(newch);
1110 /* XXXX move to generic input handler */
1112 client_input_channel_open(int type, int plen, void *ctxt)
1121 ctype = packet_get_string(&len);
1122 rchan = packet_get_int();
1123 rwindow = packet_get_int();
1124 rmaxpack = packet_get_int();
1126 debug("client_input_channel_open: ctype %s rchan %d win %d max %d",
1127 ctype, rchan, rwindow, rmaxpack);
1129 if (strcmp(ctype, "forwarded-tcpip") == 0) {
1130 c = client_request_forwarded_tcpip(ctype, rchan);
1131 } else if (strcmp(ctype, "x11") == 0) {
1132 c = client_request_x11(ctype, rchan);
1133 } else if (strcmp(ctype, "auth-agent@openssh.com") == 0) {
1134 c = client_request_agent(ctype, rchan);
1136 /* XXX duplicate : */
1138 debug("confirm %s", ctype);
1139 c->remote_id = rchan;
1140 c->remote_window = rwindow;
1141 c->remote_maxpacket = rmaxpack;
1143 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
1144 packet_put_int(c->remote_id);
1145 packet_put_int(c->self);
1146 packet_put_int(c->local_window);
1147 packet_put_int(c->local_maxpacket);
1150 debug("failure %s", ctype);
1151 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
1152 packet_put_int(rchan);
1153 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
1154 packet_put_cstring("bla bla");
1155 packet_put_cstring("");
1161 client_input_channel_req(int type, int plen, void *ctxt)
1164 int id, reply, success = 0;
1167 id = packet_get_int();
1168 rtype = packet_get_string(NULL);
1169 reply = packet_get_char();
1171 debug("client_input_channel_req: channel %d rtype %s reply %d",
1174 if (session_ident == -1) {
1175 error("client_input_channel_req: no channel %d", session_ident);
1176 } else if (id != session_ident) {
1177 error("client_input_channel_req: channel %d: wrong channel: %d",
1180 c = channel_lookup(id);
1182 error("client_input_channel_req: channel %d: unknown channel", id);
1183 } else if (strcmp(rtype, "exit-status") == 0) {
1185 exit_status = packet_get_int();
1189 packet_start(success ?
1190 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1191 packet_put_int(c->remote_id);
1198 client_init_dispatch_20(void)
1200 dispatch_init(&dispatch_protocol_error);
1201 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1202 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1203 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1204 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1205 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1206 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1207 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1208 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &client_input_channel_req);
1209 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1212 client_init_dispatch_13(void)
1214 dispatch_init(NULL);
1215 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1216 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1217 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1218 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1219 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1220 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1221 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1222 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1223 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1225 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1226 &auth_input_open_request : &deny_input_open);
1227 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1228 &x11_input_open : &deny_input_open);
1231 client_init_dispatch_15(void)
1233 client_init_dispatch_13();
1234 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1235 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1238 client_init_dispatch(void)
1241 client_init_dispatch_20();
1243 client_init_dispatch_13();
1245 client_init_dispatch_15();