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 1.40 2000/11/06 23:04:56 markus Exp $");
78 #include <openssl/dsa.h>
79 #include <openssl/rsa.h>
84 extern Options options;
86 /* Flag indicating that stdin should be redirected from /dev/null. */
87 extern int stdin_null_flag;
90 * Name of the host we are connecting to. This is the name given on the
91 * command line, or the HostName specified for the user-supplied name in a
97 * Flag to indicate that we have received a window change signal which has
98 * not yet been processed. This will cause a message indicating the new
99 * window size to be sent to the server a little later. This is volatile
100 * because this is updated in a signal handler.
102 static volatile int received_window_change_signal = 0;
104 /* Terminal modes, as saved by enter_raw_mode. */
105 static struct termios saved_tio;
108 * Flag indicating whether we are in raw mode. This is used by
109 * enter_raw_mode and leave_raw_mode.
111 static int in_raw_mode = 0;
113 /* Flag indicating whether the user\'s terminal is in non-blocking mode. */
114 static int in_non_blocking_mode = 0;
116 /* Common data for the client loop code. */
117 static int quit_pending; /* Set to non-zero to quit the client loop. */
118 static int escape_char; /* Escape character. */
119 static int escape_pending; /* Last character was the escape character */
120 static int last_was_cr; /* Last character was a newline. */
121 static int exit_status; /* Used to store the exit status of the command. */
122 static int stdin_eof; /* EOF has been encountered on standard error. */
123 static Buffer stdin_buffer; /* Buffer for stdin data. */
124 static Buffer stdout_buffer; /* Buffer for stdout data. */
125 static Buffer stderr_buffer; /* Buffer for stderr data. */
126 static unsigned long stdin_bytes, stdout_bytes, stderr_bytes;
127 static unsigned int buffer_high;/* Soft max buffer size. */
128 static int max_fd; /* Maximum file descriptor number in select(). */
129 static int connection_in; /* Connection to server (input). */
130 static int connection_out; /* Connection to server (output). */
133 void client_init_dispatch(void);
134 int session_ident = -1;
136 /* Returns the user\'s terminal to normal mode if it had been put in raw mode. */
144 if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0)
147 fatal_remove_cleanup((void (*) (void *)) leave_raw_mode, NULL);
150 /* Puts the user\'s terminal in raw mode. */
157 if (tcgetattr(fileno(stdin), &tio) < 0)
160 tio.c_iflag |= IGNPAR;
161 tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
162 tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
164 tio.c_lflag &= ~IEXTEN;
166 tio.c_oflag &= ~OPOST;
169 if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0)
173 fatal_add_cleanup((void (*) (void *)) leave_raw_mode, NULL);
176 /* Restores stdin to blocking mode. */
181 if (in_non_blocking_mode) {
182 (void) fcntl(fileno(stdin), F_SETFL, 0);
183 in_non_blocking_mode = 0;
184 fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
188 /* Puts stdin terminal in non-blocking mode. */
193 in_non_blocking_mode = 1;
194 (void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
195 fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
199 * Signal handler for the window change signal (SIGWINCH). This just sets a
200 * flag indicating that the window has changed.
204 window_change_handler(int sig)
206 received_window_change_signal = 1;
207 signal(SIGWINCH, window_change_handler);
211 * Signal handler for signals that cause the program to terminate. These
212 * signals must be trapped to restore terminal modes.
216 signal_handler(int sig)
220 if (in_non_blocking_mode)
221 leave_non_blocking();
222 channel_stop_listening();
224 fatal("Killed by signal %d.", sig);
228 * Returns current time in seconds from Jan 1, 1970 with the maximum
229 * available resolution.
236 gettimeofday(&tv, NULL);
237 return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
241 * This is called when the interactive is entered. This checks if there is
242 * an EOF coming on stdin. We must check this explicitly, as select() does
243 * not appear to wake up when redirecting from /dev/null.
247 client_check_initial_eof_on_stdin()
253 * If standard input is to be "redirected from /dev/null", we simply
254 * mark that we have seen an EOF and send an EOF message to the
255 * server. Otherwise, we try to read a single character; it appears
256 * that for some files, such /dev/null, select() never wakes up for
257 * read for this descriptor, which means that we never get EOF. This
258 * way we will get the EOF if stdin comes from /dev/null or similar.
260 if (stdin_null_flag) {
261 /* Fake EOF on stdin. */
262 debug("Sending eof.");
264 packet_start(SSH_CMSG_EOF);
267 enter_non_blocking();
269 /* Check for immediate EOF on stdin. */
270 len = read(fileno(stdin), buf, 1);
272 /* EOF. Record that we have seen it and send EOF to server. */
273 debug("Sending eof.");
275 packet_start(SSH_CMSG_EOF);
277 } else if (len > 0) {
279 * Got data. We must store the data in the buffer,
280 * and also process it as an escape character if
283 if ((unsigned char) buf[0] == escape_char)
286 buffer_append(&stdin_buffer, buf, 1);
290 leave_non_blocking();
296 * Make packets from buffered stdin data, and buffer them for sending to the
301 client_make_packets_from_stdin_data()
305 /* Send buffered stdin data to the server. */
306 while (buffer_len(&stdin_buffer) > 0 &&
307 packet_not_very_much_data_to_write()) {
308 len = buffer_len(&stdin_buffer);
309 /* Keep the packets at reasonable size. */
310 if (len > packet_get_maxsize())
311 len = packet_get_maxsize();
312 packet_start(SSH_CMSG_STDIN_DATA);
313 packet_put_string(buffer_ptr(&stdin_buffer), len);
315 buffer_consume(&stdin_buffer, len);
316 /* If we have a pending EOF, send it now. */
317 if (stdin_eof && buffer_len(&stdin_buffer) == 0) {
318 packet_start(SSH_CMSG_EOF);
325 * Checks if the client window has changed, and sends a packet about it to
326 * the server if so. The actual change is detected elsewhere (by a software
327 * interrupt on Unix); this just checks the flag and sends a message if
332 client_check_window_change()
336 if (! received_window_change_signal)
339 received_window_change_signal = 0;
341 if (ioctl(fileno(stdin), TIOCGWINSZ, &ws) < 0)
344 debug2("client_check_window_change: changed");
347 channel_request_start(session_ident, "window-change", 0);
348 packet_put_int(ws.ws_col);
349 packet_put_int(ws.ws_row);
350 packet_put_int(ws.ws_xpixel);
351 packet_put_int(ws.ws_ypixel);
354 packet_start(SSH_CMSG_WINDOW_SIZE);
355 packet_put_int(ws.ws_row);
356 packet_put_int(ws.ws_col);
357 packet_put_int(ws.ws_xpixel);
358 packet_put_int(ws.ws_ypixel);
364 * Waits until the client can do something (some data becomes available on
365 * one of the file descriptors).
369 client_wait_until_can_do_something(fd_set * readset, fd_set * writeset)
371 /* Initialize select masks. */
376 /* Read from the connection, unless our buffers are full. */
377 if (buffer_len(&stdout_buffer) < buffer_high &&
378 buffer_len(&stderr_buffer) < buffer_high &&
379 channel_not_very_much_buffered_data())
380 FD_SET(connection_in, readset);
382 * Read from stdin, unless we have seen EOF or have very much
383 * buffered data to send to the server.
385 if (!stdin_eof && packet_not_very_much_data_to_write())
386 FD_SET(fileno(stdin), readset);
388 /* Select stdout/stderr if have data in buffer. */
389 if (buffer_len(&stdout_buffer) > 0)
390 FD_SET(fileno(stdout), writeset);
391 if (buffer_len(&stderr_buffer) > 0)
392 FD_SET(fileno(stderr), writeset);
394 FD_SET(connection_in, readset);
397 /* Add any selections by the channel mechanism. */
398 channel_prepare_select(readset, writeset);
400 /* Select server connection if have data to write to the server. */
401 if (packet_have_data_to_write())
402 FD_SET(connection_out, writeset);
405 /* Update maximum file descriptor number, if appropriate. */
406 if (channel_max_fd() > max_fd)
407 max_fd = channel_max_fd();
410 * Wait for something to happen. This will suspend the process until
411 * some selected descriptor can be read, written, or has some other
412 * event pending. Note: if you want to implement SSH_MSG_IGNORE
413 * messages to fool traffic analysis, this might be the place to do
414 * it: just have a random timeout for the select, and send a random
415 * SSH_MSG_IGNORE packet when the timeout expires.
418 if (select(max_fd + 1, readset, writeset, NULL, NULL) < 0) {
420 /* Some systems fail to clear these automatically. */
425 /* Note: we might still have data in the buffers. */
426 snprintf(buf, sizeof buf, "select: %s\r\n", strerror(errno));
427 buffer_append(&stderr_buffer, buf, strlen(buf));
428 stderr_bytes += strlen(buf);
434 client_suspend_self(Buffer *bin, Buffer *bout, Buffer *berr)
436 struct winsize oldws, newws;
438 /* Flush stdout and stderr buffers. */
439 if (buffer_len(bout) > 0)
440 atomicio(write, fileno(stdout), buffer_ptr(bout), buffer_len(bout));
441 if (buffer_len(berr) > 0)
442 atomicio(write, fileno(stderr), buffer_ptr(berr), buffer_len(berr));
447 * Free (and clear) the buffer to reduce the amount of data that gets
454 /* Save old window size. */
455 ioctl(fileno(stdin), TIOCGWINSZ, &oldws);
457 /* Send the suspend signal to the program itself. */
458 kill(getpid(), SIGTSTP);
460 /* Check if the window size has changed. */
461 if (ioctl(fileno(stdin), TIOCGWINSZ, &newws) >= 0 &&
462 (oldws.ws_row != newws.ws_row ||
463 oldws.ws_col != newws.ws_col ||
464 oldws.ws_xpixel != newws.ws_xpixel ||
465 oldws.ws_ypixel != newws.ws_ypixel))
466 received_window_change_signal = 1;
468 /* OK, we have been continued by the user. Reinitialize buffers. */
477 client_process_net_input(fd_set * readset)
483 * Read input from the server, and add any such data to the buffer of
484 * the packet subsystem.
486 if (FD_ISSET(connection_in, readset)) {
487 /* Read as much as possible. */
488 len = read(connection_in, buf, sizeof(buf));
490 /* Received EOF. The remote host has closed the connection. */
491 snprintf(buf, sizeof buf, "Connection to %.300s closed by remote host.\r\n",
493 buffer_append(&stderr_buffer, buf, strlen(buf));
494 stderr_bytes += strlen(buf);
499 * There is a kernel bug on Solaris that causes select to
500 * sometimes wake up even though there is no data available.
502 if (len < 0 && errno == EAGAIN)
506 /* An error has encountered. Perhaps there is a network problem. */
507 snprintf(buf, sizeof buf, "Read from remote host %.300s: %.100s\r\n",
508 host, strerror(errno));
509 buffer_append(&stderr_buffer, buf, strlen(buf));
510 stderr_bytes += strlen(buf);
514 packet_process_incoming(buf, len);
518 /* process the characters one by one */
520 process_escapes(Buffer *bin, Buffer *bout, Buffer *berr, char *buf, int len)
529 for (i = 0; i < len; i++) {
530 /* Get one character at a time. */
533 if (escape_pending) {
534 /* We have previously seen an escape character. */
535 /* Clear the flag now. */
538 /* Process the escaped character. */
541 /* Terminate the connection. */
542 snprintf(string, sizeof string, "%c.\r\n", escape_char);
543 buffer_append(berr, string, strlen(string));
544 /*stderr_bytes += strlen(string); XXX*/
550 /* Suspend the program. */
551 /* Print a message to that effect to the user. */
552 snprintf(string, sizeof string, "%c^Z [suspend ssh]\r\n", escape_char);
553 buffer_append(berr, string, strlen(string));
554 /*stderr_bytes += strlen(string); XXX*/
556 /* Restore terminal modes and suspend. */
557 client_suspend_self(bin, bout, berr);
559 /* We have been continued. */
563 /* XXX does not work yet with proto 2 */
567 * Detach the program (continue to serve connections,
568 * but put in background and no more new connections).
572 * Sending SSH_CMSG_EOF alone does not always appear
573 * to be enough. So we try to send an EOF character
576 packet_start(SSH_CMSG_STDIN_DATA);
577 packet_put_string("\004", 1);
581 if (buffer_len(bin) == 0) {
582 packet_start(SSH_CMSG_EOF);
586 /* Restore tty modes. */
589 /* Stop listening for new connections. */
590 channel_stop_listening();
592 printf("%c& [backgrounded]\n", escape_char);
594 /* Fork into background. */
597 error("fork: %.100s", strerror(errno));
600 if (pid != 0) { /* This is the parent. */
601 /* The parent just exits. */
604 /* The child continues serving connections. */
608 snprintf(string, sizeof string,
610 Supported escape sequences:\r\n\
611 ~. - terminate connection\r\n\
612 ~^Z - suspend ssh\r\n\
613 ~# - list forwarded connections\r\n\
614 ~& - background ssh (when waiting for connections to terminate)\r\n\
615 ~? - this message\r\n\
616 ~~ - send the escape character by typing it twice\r\n\
617 (Note that escapes are only recognized immediately after newline.)\r\n",
619 buffer_append(berr, string, strlen(string));
623 snprintf(string, sizeof string, "%c#\r\n", escape_char);
624 buffer_append(berr, string, strlen(string));
625 s = channel_open_message();
626 buffer_append(berr, s, strlen(s));
631 if (ch != escape_char) {
632 buffer_put_char(bin, escape_char);
635 /* Escaped characters fall through here */
640 * The previous character was not an escape char. Check if this
643 if (last_was_cr && ch == escape_char) {
644 /* It is. Set the flag and continue to next character. */
651 * Normal character. Record whether it was a newline,
652 * and append it to the buffer.
654 last_was_cr = (ch == '\r' || ch == '\n');
655 buffer_put_char(bin, ch);
662 client_process_input(fd_set * readset)
668 /* Read input from stdin. */
669 if (FD_ISSET(fileno(stdin), readset)) {
670 /* Read as much as possible. */
671 len = read(fileno(stdin), buf, sizeof(buf));
674 * Received EOF or error. They are treated
675 * similarly, except that an error message is printed
676 * if it was an error condition.
679 snprintf(buf, sizeof buf, "read: %.100s\r\n", strerror(errno));
680 buffer_append(&stderr_buffer, buf, strlen(buf));
681 stderr_bytes += strlen(buf);
683 /* Mark that we have seen EOF. */
686 * Send an EOF message to the server unless there is
687 * data in the buffer. If there is data in the
688 * buffer, no message will be sent now. Code
689 * elsewhere will send the EOF when the buffer
690 * becomes empty if stdin_eof is set.
692 if (buffer_len(&stdin_buffer) == 0) {
693 packet_start(SSH_CMSG_EOF);
696 } else if (escape_char == -1) {
698 * Normal successful read, and no escape character.
699 * Just append the data to buffer.
701 buffer_append(&stdin_buffer, buf, len);
705 * Normal, successful read. But we have an escape character
706 * and have to process the characters one by one.
708 ret = process_escapes(&stdin_buffer, &stdout_buffer, &stderr_buffer, buf, len);
717 client_process_output(fd_set * writeset)
722 /* Write buffered output to stdout. */
723 if (FD_ISSET(fileno(stdout), writeset)) {
724 /* Write as much data as possible. */
725 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
726 buffer_len(&stdout_buffer));
732 * An error or EOF was encountered. Put an
733 * error message to stderr buffer.
735 snprintf(buf, sizeof buf, "write stdout: %.50s\r\n", strerror(errno));
736 buffer_append(&stderr_buffer, buf, strlen(buf));
737 stderr_bytes += strlen(buf);
742 /* Consume printed data from the buffer. */
743 buffer_consume(&stdout_buffer, len);
745 /* Write buffered output to stderr. */
746 if (FD_ISSET(fileno(stderr), writeset)) {
747 /* Write as much data as possible. */
748 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
749 buffer_len(&stderr_buffer));
754 /* EOF or error, but can't even print error message. */
759 /* Consume printed characters from the buffer. */
760 buffer_consume(&stderr_buffer, len);
765 * Get packets from the connection input buffer, and process them as long as
766 * there are packets available.
768 * Any unknown packets received during the actual
769 * session cause the session to terminate. This is
770 * intended to make debugging easier since no
771 * confirmations are sent. Any compatible protocol
772 * extensions must be negotiated during the
777 client_process_buffered_input_packets()
779 dispatch_run(DISPATCH_NONBLOCK, &quit_pending, NULL);
782 /* scan buf[] for '~' before sending data to the peer */
785 simple_escape_filter(Channel *c, char *buf, int len)
787 /* XXX we assume c->extended is writeable */
788 return process_escapes(&c->input, &c->output, &c->extended, buf, len);
792 * Implements the interactive session with the server. This is called after
793 * the user has been authenticated, and a command has been started on the
794 * remote host. If escape_char != -1, it is the character used as an escape
795 * character for terminating or suspending the session.
799 client_loop(int have_pty, int escape_char_arg, int ssh2_chan_id)
801 double start_time, total_time;
805 debug("Entering interactive session.");
807 start_time = get_current_time();
809 /* Initialize variables. */
814 buffer_high = 64 * 1024;
815 connection_in = packet_get_connection_in();
816 connection_out = packet_get_connection_out();
817 max_fd = connection_in;
818 if (connection_out > max_fd)
819 max_fd = connection_out;
824 escape_char = escape_char_arg;
826 /* Initialize buffers. */
827 buffer_init(&stdin_buffer);
828 buffer_init(&stdout_buffer);
829 buffer_init(&stderr_buffer);
831 client_init_dispatch();
833 /* Set signal handlers to restore non-blocking mode. */
834 signal(SIGINT, signal_handler);
835 signal(SIGQUIT, signal_handler);
836 signal(SIGTERM, signal_handler);
837 signal(SIGPIPE, SIG_IGN);
839 signal(SIGWINCH, window_change_handler);
844 /* Check if we should immediately send eof on stdin. */
846 client_check_initial_eof_on_stdin();
848 if (compat20 && escape_char != -1)
849 channel_register_filter(ssh2_chan_id, simple_escape_filter);
851 /* Main loop of the client for the interactive session mode. */
852 while (!quit_pending) {
853 fd_set readset, writeset;
855 /* Process buffered packets sent by the server. */
856 client_process_buffered_input_packets();
858 if (compat20 && !channel_still_open()) {
859 debug2("!channel_still_open.");
864 * Make packets of buffered stdin data, and buffer them for
865 * sending to the server.
868 client_make_packets_from_stdin_data();
871 * Make packets from buffered channel data, and buffer them
872 * for sending to the server.
874 if (packet_not_very_much_data_to_write())
875 channel_output_poll();
878 * Check if the window size has changed, and buffer a message
879 * about it to the server if so.
881 client_check_window_change();
887 * Wait until we have something to do (something becomes
888 * available on one of the descriptors).
890 client_wait_until_can_do_something(&readset, &writeset);
895 /* Do channel operations. */
896 channel_after_select(&readset, &writeset);
898 /* Buffer input from the connection. */
899 client_process_net_input(&readset);
905 /* Buffer data from stdin */
906 client_process_input(&readset);
908 * Process output to stdout and stderr. Output to
909 * the connection is processed elsewhere (above).
911 client_process_output(&writeset);
914 /* Send as much buffered packet data as possible to the sender. */
915 if (FD_ISSET(connection_out, &writeset))
919 /* Terminate the session. */
921 /* Stop watching for window change. */
923 signal(SIGWINCH, SIG_DFL);
925 /* Stop listening for connections. */
926 channel_stop_listening();
929 * In interactive mode (with pseudo tty) display a message indicating
930 * that the connection has been closed.
932 if (have_pty && options.log_level != SYSLOG_LEVEL_QUIET) {
933 snprintf(buf, sizeof buf, "Connection to %.64s closed.\r\n", host);
934 buffer_append(&stderr_buffer, buf, strlen(buf));
935 stderr_bytes += strlen(buf);
937 /* Output any buffered data for stdout. */
938 while (buffer_len(&stdout_buffer) > 0) {
939 len = write(fileno(stdout), buffer_ptr(&stdout_buffer),
940 buffer_len(&stdout_buffer));
942 error("Write failed flushing stdout buffer.");
945 buffer_consume(&stdout_buffer, len);
948 /* Output any buffered data for stderr. */
949 while (buffer_len(&stderr_buffer) > 0) {
950 len = write(fileno(stderr), buffer_ptr(&stderr_buffer),
951 buffer_len(&stderr_buffer));
953 error("Write failed flushing stderr buffer.");
956 buffer_consume(&stderr_buffer, len);
962 /* Clear and free any buffers. */
963 memset(buf, 0, sizeof(buf));
964 buffer_free(&stdin_buffer);
965 buffer_free(&stdout_buffer);
966 buffer_free(&stderr_buffer);
968 /* Report bytes transferred, and transfer rates. */
969 total_time = get_current_time() - start_time;
970 debug("Transferred: stdin %lu, stdout %lu, stderr %lu bytes in %.1f seconds",
971 stdin_bytes, stdout_bytes, stderr_bytes, total_time);
973 debug("Bytes per second: stdin %.1f, stdout %.1f, stderr %.1f",
974 stdin_bytes / total_time, stdout_bytes / total_time,
975 stderr_bytes / total_time);
977 /* Return the exit status of the program. */
978 debug("Exit status %d", exit_status);
985 client_input_stdout_data(int type, int plen, void *ctxt)
987 unsigned int data_len;
988 char *data = packet_get_string(&data_len);
989 packet_integrity_check(plen, 4 + data_len, type);
990 buffer_append(&stdout_buffer, data, data_len);
991 stdout_bytes += data_len;
992 memset(data, 0, data_len);
996 client_input_stderr_data(int type, int plen, void *ctxt)
998 unsigned int data_len;
999 char *data = packet_get_string(&data_len);
1000 packet_integrity_check(plen, 4 + data_len, type);
1001 buffer_append(&stderr_buffer, data, data_len);
1002 stdout_bytes += data_len;
1003 memset(data, 0, data_len);
1007 client_input_exit_status(int type, int plen, void *ctxt)
1009 packet_integrity_check(plen, 4, type);
1010 exit_status = packet_get_int();
1011 /* Acknowledge the exit. */
1012 packet_start(SSH_CMSG_EXIT_CONFIRMATION);
1015 * Must wait for packet to be sent since we are
1018 packet_write_wait();
1019 /* Flag that we want to exit. */
1024 client_request_forwarded_tcpip(const char *request_type, int rchan)
1027 char *listen_address, *originator_address;
1028 int listen_port, originator_port;
1031 /* Get rest of the packet */
1032 listen_address = packet_get_string(NULL);
1033 listen_port = packet_get_int();
1034 originator_address = packet_get_string(NULL);
1035 originator_port = packet_get_int();
1038 debug("client_request_forwarded_tcpip: listen %s port %d, originator %s port %d",
1039 listen_address, listen_port, originator_address, originator_port);
1041 sock = channel_connect_by_listen_adress(listen_port);
1043 newch = channel_new("forwarded-tcpip",
1044 SSH_CHANNEL_OPEN, sock, sock, -1,
1045 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_WINDOW_DEFAULT, 0,
1046 xstrdup(originator_address), 1);
1047 c = channel_lookup(newch);
1049 xfree(originator_address);
1050 xfree(listen_address);
1055 client_request_x11(const char *request_type, int rchan)
1059 int originator_port;
1062 if (!options.forward_x11) {
1063 error("Warning: ssh server tried X11 forwarding.");
1064 error("Warning: this is probably a break in attempt by a malicious server.");
1067 originator = packet_get_string(NULL);
1068 if (datafellows & SSH_BUG_X11FWD) {
1069 debug2("buggy server: x11 request w/o originator_port");
1070 originator_port = 0;
1072 originator_port = packet_get_int();
1075 /* XXX check permission */
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("");
1162 client_init_dispatch_20()
1164 dispatch_init(&dispatch_protocol_error);
1165 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1166 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1167 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1168 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1169 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &client_input_channel_open);
1170 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1171 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1172 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &channel_input_channel_request);
1173 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1176 client_init_dispatch_13()
1178 dispatch_init(NULL);
1179 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1180 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1181 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1182 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1183 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1184 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1185 dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
1186 dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
1187 dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
1189 dispatch_set(SSH_SMSG_AGENT_OPEN, options.forward_agent ?
1190 &auth_input_open_request : &deny_input_open);
1191 dispatch_set(SSH_SMSG_X11_OPEN, options.forward_x11 ?
1192 &x11_input_open : &deny_input_open);
1195 client_init_dispatch_15()
1197 client_init_dispatch_13();
1198 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1199 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
1202 client_init_dispatch()
1205 client_init_dispatch_20();
1207 client_init_dispatch_13();
1209 client_init_dispatch_15();
1213 client_input_channel_req(int id, void *arg)
1221 rtype = packet_get_string(&len);
1222 reply = packet_get_char();
1224 debug("client_input_channel_req: rtype %s reply %d", rtype, reply);
1226 c = channel_lookup(id);
1228 fatal("client_input_channel_req: channel %d: bad channel", id);
1230 if (session_ident == -1) {
1231 error("client_input_channel_req: no channel %d", id);
1232 } else if (id != session_ident) {
1233 error("client_input_channel_req: bad channel %d != %d",
1235 } else if (strcmp(rtype, "exit-status") == 0) {
1237 exit_status = packet_get_int();
1241 packet_start(success ?
1242 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1243 packet_put_int(c->remote_id);
1250 client_set_session_ident(int id)
1252 debug2("client_set_session_ident: id %d", id);
1254 channel_register_callback(id, SSH2_MSG_CHANNEL_REQUEST,
1255 client_input_channel_req, (void *)0);