2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * Server main loop for handling the interactive session.
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".
13 * SSH2 support by Markus Friedl.
14 * Copyright (c) 2000, 2001 Markus Friedl. 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.
38 RCSID("$OpenBSD: serverloop.c,v 1.104 2002/09/19 16:03:15 stevesk Exp $");
39 RCSID("$FreeBSD: src/crypto/openssh/serverloop.c,v 1.1.1.1.2.7 2003/02/03 17:31:07 des Exp $");
55 #include "auth-options.h"
56 #include "serverloop.h"
60 extern ServerOptions options;
64 static Authctxt *xxx_authctxt;
66 static Buffer stdin_buffer; /* Buffer for stdin data. */
67 static Buffer stdout_buffer; /* Buffer for stdout data. */
68 static Buffer stderr_buffer; /* Buffer for stderr data. */
69 static int fdin; /* Descriptor for stdin (for writing) */
70 static int fdout; /* Descriptor for stdout (for reading);
71 May be same number as fdin. */
72 static int fderr; /* Descriptor for stderr. May be -1. */
73 static long stdin_bytes = 0; /* Number of bytes written to stdin. */
74 static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */
75 static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */
76 static long fdout_bytes = 0; /* Number of stdout bytes read from program. */
77 static int stdin_eof = 0; /* EOF message received from client. */
78 static int fdout_eof = 0; /* EOF encountered reading from fdout. */
79 static int fderr_eof = 0; /* EOF encountered readung from fderr. */
80 static int fdin_is_tty = 0; /* fdin points to a tty. */
81 static int connection_in; /* Connection to client (input). */
82 static int connection_out; /* Connection to client (output). */
83 static int connection_closed = 0; /* Connection to client closed. */
84 static u_int buffer_high; /* "Soft" max buffer size. */
85 static int client_alive_timeouts = 0;
88 * This SIGCHLD kludge is used to detect when the child exits. The server
89 * will exit after that, as soon as forwarded connections have terminated.
92 static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */
95 static void server_init_dispatch(void);
98 * we write to this pipe if a SIGCHLD is caught in order to avoid
99 * the race between select() and child_terminated
101 static int notify_pipe[2];
105 if (pipe(notify_pipe) < 0) {
106 error("pipe(notify_pipe) failed %s", strerror(errno));
107 } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) ||
108 (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) {
109 error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno));
110 close(notify_pipe[0]);
111 close(notify_pipe[1]);
113 set_nonblock(notify_pipe[0]);
114 set_nonblock(notify_pipe[1]);
117 notify_pipe[0] = -1; /* read end */
118 notify_pipe[1] = -1; /* write end */
123 if (notify_pipe[1] != -1)
124 write(notify_pipe[1], "", 1);
127 notify_prepare(fd_set *readset)
129 if (notify_pipe[0] != -1)
130 FD_SET(notify_pipe[0], readset);
133 notify_done(fd_set *readset)
137 if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset))
138 while (read(notify_pipe[0], &c, 1) != -1)
139 debug2("notify_done: reading");
143 sigchld_handler(int sig)
145 int save_errno = errno;
146 debug("Received SIGCHLD.");
147 child_terminated = 1;
149 mysignal(SIGCHLD, sigchld_handler);
156 * Make packets from buffered stderr data, and buffer it for sending
160 make_packets_from_stderr_data(void)
164 /* Send buffered stderr data to the client. */
165 while (buffer_len(&stderr_buffer) > 0 &&
166 packet_not_very_much_data_to_write()) {
167 len = buffer_len(&stderr_buffer);
168 if (packet_is_interactive()) {
172 /* Keep the packets at reasonable size. */
173 if (len > packet_get_maxsize())
174 len = packet_get_maxsize();
176 packet_start(SSH_SMSG_STDERR_DATA);
177 packet_put_string(buffer_ptr(&stderr_buffer), len);
179 buffer_consume(&stderr_buffer, len);
185 * Make packets from buffered stdout data, and buffer it for sending to the
189 make_packets_from_stdout_data(void)
193 /* Send buffered stdout data to the client. */
194 while (buffer_len(&stdout_buffer) > 0 &&
195 packet_not_very_much_data_to_write()) {
196 len = buffer_len(&stdout_buffer);
197 if (packet_is_interactive()) {
201 /* Keep the packets at reasonable size. */
202 if (len > packet_get_maxsize())
203 len = packet_get_maxsize();
205 packet_start(SSH_SMSG_STDOUT_DATA);
206 packet_put_string(buffer_ptr(&stdout_buffer), len);
208 buffer_consume(&stdout_buffer, len);
214 client_alive_check(void)
216 static int had_channel = 0;
219 id = channel_find_open();
223 packet_disconnect("No open channels after timeout!");
227 /* timeout, check to see how many we have had */
228 if (++client_alive_timeouts > options.client_alive_count_max)
229 packet_disconnect("Timeout, your session not responding.");
232 * send a bogus channel request with "wantreply",
233 * we should get back a failure
235 channel_request_start(id, "keepalive@openssh.com", 1);
240 * Sleep in select() until we can do something. This will initialize the
241 * select masks. Upon return, the masks will indicate which descriptors
242 * have data or can accept data. Optionally, a maximum time can be specified
243 * for the duration of the wait (0 = infinite).
246 wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
247 int *nallocp, u_int max_time_milliseconds)
249 struct timeval tv, *tvp;
251 int client_alive_scheduled = 0;
254 * if using client_alive, set the max timeout accordingly,
255 * and indicate that this particular timeout was for client
256 * alive by setting the client_alive_scheduled flag.
258 * this could be randomized somewhat to make traffic
259 * analysis more difficult, but we're not doing it yet.
262 max_time_milliseconds == 0 && options.client_alive_interval) {
263 client_alive_scheduled = 1;
264 max_time_milliseconds = options.client_alive_interval * 1000;
267 /* Allocate and update select() masks for channel descriptors. */
268 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0);
272 /* wrong: bad condition XXX */
273 if (channel_not_very_much_buffered_data())
275 FD_SET(connection_in, *readsetp);
278 * Read packets from the client unless we have too much
279 * buffered stdin or channel data.
281 if (buffer_len(&stdin_buffer) < buffer_high &&
282 channel_not_very_much_buffered_data())
283 FD_SET(connection_in, *readsetp);
285 * If there is not too much data already buffered going to
286 * the client, try to get some more data from the program.
288 if (packet_not_very_much_data_to_write()) {
290 FD_SET(fdout, *readsetp);
292 FD_SET(fderr, *readsetp);
295 * If we have buffered data, try to write some of that data
298 if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
299 FD_SET(fdin, *writesetp);
301 notify_prepare(*readsetp);
304 * If we have buffered packet data going to the client, mark that
307 if (packet_have_data_to_write())
308 FD_SET(connection_out, *writesetp);
311 * If child has terminated and there is enough buffer space to read
312 * from it, then read as much as is available and exit.
314 if (child_terminated && packet_not_very_much_data_to_write())
315 if (max_time_milliseconds == 0 || client_alive_scheduled)
316 max_time_milliseconds = 100;
318 if (max_time_milliseconds == 0)
321 tv.tv_sec = max_time_milliseconds / 1000;
322 tv.tv_usec = 1000 * (max_time_milliseconds % 1000);
326 /* Wait for something to happen, or the timeout to expire. */
327 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
330 memset(*readsetp, 0, *nallocp);
331 memset(*writesetp, 0, *nallocp);
333 error("select: %.100s", strerror(errno));
334 } else if (ret == 0 && client_alive_scheduled)
335 client_alive_check();
337 notify_done(*readsetp);
341 * Processes input from the client and the program. Input data is stored
342 * in buffers and processed later.
345 process_input(fd_set * readset)
350 /* Read and buffer any input data from the client. */
351 if (FD_ISSET(connection_in, readset)) {
352 len = read(connection_in, buf, sizeof(buf));
354 verbose("Connection closed by %.100s",
355 get_remote_ipaddr());
356 connection_closed = 1;
360 } else if (len < 0) {
361 if (errno != EINTR && errno != EAGAIN) {
362 verbose("Read error from remote host "
364 get_remote_ipaddr(), strerror(errno));
368 /* Buffer any received data. */
369 packet_process_incoming(buf, len);
375 /* Read and buffer any available stdout data from the program. */
376 if (!fdout_eof && FD_ISSET(fdout, readset)) {
377 len = read(fdout, buf, sizeof(buf));
378 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
380 } else if (len <= 0) {
383 buffer_append(&stdout_buffer, buf, len);
387 /* Read and buffer any available stderr data from the program. */
388 if (!fderr_eof && FD_ISSET(fderr, readset)) {
389 len = read(fderr, buf, sizeof(buf));
390 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
392 } else if (len <= 0) {
395 buffer_append(&stderr_buffer, buf, len);
401 * Sends data from internal buffers to client program stdin.
404 process_output(fd_set * writeset)
411 /* Write buffered data to program stdin. */
412 if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) {
413 data = buffer_ptr(&stdin_buffer);
414 dlen = buffer_len(&stdin_buffer);
415 len = write(fdin, data, dlen);
416 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
418 } else if (len <= 0) {
422 shutdown(fdin, SHUT_WR); /* We will no longer send. */
425 /* Successful write. */
426 if (fdin_is_tty && dlen >= 1 && data[0] != '\r' &&
427 tcgetattr(fdin, &tio) == 0 &&
428 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
430 * Simulate echo to reduce the impact of
433 packet_send_ignore(len);
436 /* Consume the data from the buffer. */
437 buffer_consume(&stdin_buffer, len);
438 /* Update the count of bytes written to the program. */
442 /* Send any buffered packet data to the client. */
443 if (FD_ISSET(connection_out, writeset))
448 * Wait until all buffered output has been sent to the client.
449 * This is used when the program terminates.
454 /* Send any buffered stdout data to the client. */
455 if (buffer_len(&stdout_buffer) > 0) {
456 packet_start(SSH_SMSG_STDOUT_DATA);
457 packet_put_string(buffer_ptr(&stdout_buffer),
458 buffer_len(&stdout_buffer));
460 /* Update the count of sent bytes. */
461 stdout_bytes += buffer_len(&stdout_buffer);
463 /* Send any buffered stderr data to the client. */
464 if (buffer_len(&stderr_buffer) > 0) {
465 packet_start(SSH_SMSG_STDERR_DATA);
466 packet_put_string(buffer_ptr(&stderr_buffer),
467 buffer_len(&stderr_buffer));
469 /* Update the count of sent bytes. */
470 stderr_bytes += buffer_len(&stderr_buffer);
472 /* Wait until all buffered data has been written to the client. */
477 process_buffered_input_packets(void)
479 dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL);
483 * Performs the interactive session. This handles data transmission between
484 * the client and the program. Note that the notion of stdin, stdout, and
485 * stderr in this function is sort of reversed: this function writes to
486 * stdin (of the child program), and reads from stdout and stderr (of the
490 server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
492 fd_set *readset = NULL, *writeset = NULL;
493 int max_fd = 0, nalloc = 0;
494 int wait_status; /* Status returned by wait(). */
495 pid_t wait_pid; /* pid returned by wait(). */
496 int waiting_termination = 0; /* Have displayed waiting close message. */
497 u_int max_time_milliseconds;
498 u_int previous_stdout_buffer_bytes;
499 u_int stdout_buffer_bytes;
502 debug("Entering interactive session.");
504 /* Initialize the SIGCHLD kludge. */
505 child_terminated = 0;
506 mysignal(SIGCHLD, sigchld_handler);
508 /* Initialize our global variables. */
516 /* we don't have stderr for interactive terminal sessions, see below */
520 if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin))
523 connection_in = packet_get_connection_in();
524 connection_out = packet_get_connection_out();
528 previous_stdout_buffer_bytes = 0;
530 /* Set approximate I/O buffer size. */
531 if (packet_is_interactive())
534 buffer_high = 64 * 1024;
537 /* Initialize max_fd to the maximum of the known file descriptors. */
538 max_fd = MAX(connection_in, connection_out);
539 max_fd = MAX(max_fd, fdin);
540 max_fd = MAX(max_fd, fdout);
542 max_fd = MAX(max_fd, fderr);
545 /* Initialize Initialize buffers. */
546 buffer_init(&stdin_buffer);
547 buffer_init(&stdout_buffer);
548 buffer_init(&stderr_buffer);
551 * If we have no separate fderr (which is the case when we have a pty
552 * - there we cannot make difference between data sent to stdout and
553 * stderr), indicate that we have seen an EOF from stderr. This way
554 * we don\'t need to check the descriptor everywhere.
559 server_init_dispatch();
561 /* Main loop of the server for the interactive session mode. */
564 /* Process buffered packets from the client. */
565 process_buffered_input_packets();
568 * If we have received eof, and there is no more pending
569 * input data, cause a real eof by closing fdin.
571 if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
575 shutdown(fdin, SHUT_WR); /* We will no longer send. */
578 /* Make packets from buffered stderr data to send to the client. */
579 make_packets_from_stderr_data();
582 * Make packets from buffered stdout data to send to the
583 * client. If there is very little to send, this arranges to
584 * not send them now, but to wait a short while to see if we
585 * are getting more data. This is necessary, as some systems
586 * wake up readers from a pty after each separate character.
588 max_time_milliseconds = 0;
589 stdout_buffer_bytes = buffer_len(&stdout_buffer);
590 if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
591 stdout_buffer_bytes != previous_stdout_buffer_bytes) {
592 /* try again after a while */
593 max_time_milliseconds = 10;
596 make_packets_from_stdout_data();
598 previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);
600 /* Send channel data to the client. */
601 if (packet_not_very_much_data_to_write())
602 channel_output_poll();
605 * Bail out of the loop if the program has closed its output
606 * descriptors, and we have no more data to send to the
607 * client, and there is no pending buffered data.
609 if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
610 buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
611 if (!channel_still_open())
613 if (!waiting_termination) {
614 const char *s = "Waiting for forwarded connections to terminate...\r\n";
616 waiting_termination = 1;
617 buffer_append(&stderr_buffer, s, strlen(s));
619 /* Display list of open channels. */
620 cp = channel_open_message();
621 buffer_append(&stderr_buffer, cp, strlen(cp));
625 max_fd = MAX(connection_in, connection_out);
626 max_fd = MAX(max_fd, fdin);
627 max_fd = MAX(max_fd, fdout);
628 max_fd = MAX(max_fd, fderr);
629 max_fd = MAX(max_fd, notify_pipe[0]);
631 /* Sleep in select() until we can do something. */
632 wait_until_can_do_something(&readset, &writeset, &max_fd,
633 &nalloc, max_time_milliseconds);
635 /* Process any channel events. */
636 channel_after_select(readset, writeset);
638 /* Process input from the client and from program stdout/stderr. */
639 process_input(readset);
641 /* Process output to the client and to program stdin. */
642 process_output(writeset);
649 /* Cleanup and termination code. */
651 /* Wait until all output has been sent to the client. */
654 debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
655 stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);
657 /* Free and clear the buffers. */
658 buffer_free(&stdin_buffer);
659 buffer_free(&stdout_buffer);
660 buffer_free(&stderr_buffer);
662 /* Close the file descriptors. */
677 /* We no longer want our SIGCHLD handler to be called. */
678 mysignal(SIGCHLD, SIG_DFL);
680 while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0)
682 packet_disconnect("wait: %.100s", strerror(errno));
684 error("Strange, wait returned pid %ld, expected %ld",
685 (long)wait_pid, (long)pid);
687 /* Check if it exited normally. */
688 if (WIFEXITED(wait_status)) {
689 /* Yes, normal exit. Get exit status and send it to the client. */
690 debug("Command exited with status %d.", WEXITSTATUS(wait_status));
691 packet_start(SSH_SMSG_EXITSTATUS);
692 packet_put_int(WEXITSTATUS(wait_status));
697 * Wait for exit confirmation. Note that there might be
698 * other packets coming before it; however, the program has
699 * already died so we just ignore them. The client is
700 * supposed to respond with the confirmation when it receives
704 type = packet_read();
706 while (type != SSH_CMSG_EXIT_CONFIRMATION);
708 debug("Received exit confirmation.");
711 /* Check if the program terminated due to a signal. */
712 if (WIFSIGNALED(wait_status))
713 packet_disconnect("Command terminated on signal %d.",
714 WTERMSIG(wait_status));
716 /* Some weird exit cause. Just exit. */
717 packet_disconnect("wait returned status %04x.", wait_status);
722 collect_children(void)
728 /* block SIGCHLD while we check for dead children */
730 sigaddset(&nset, SIGCHLD);
731 sigprocmask(SIG_BLOCK, &nset, &oset);
732 if (child_terminated) {
733 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
734 (pid < 0 && errno == EINTR))
736 session_close_by_pid(pid, status);
737 child_terminated = 0;
739 sigprocmask(SIG_SETMASK, &oset, NULL);
743 server_loop2(Authctxt *authctxt)
745 fd_set *readset = NULL, *writeset = NULL;
746 int rekeying = 0, max_fd, nalloc = 0;
748 debug("Entering interactive session for SSH2.");
750 mysignal(SIGCHLD, sigchld_handler);
751 child_terminated = 0;
752 connection_in = packet_get_connection_in();
753 connection_out = packet_get_connection_out();
757 max_fd = MAX(connection_in, connection_out);
758 max_fd = MAX(max_fd, notify_pipe[0]);
760 xxx_authctxt = authctxt;
762 server_init_dispatch();
765 process_buffered_input_packets();
767 rekeying = (xxx_kex != NULL && !xxx_kex->done);
769 if (!rekeying && packet_not_very_much_data_to_write())
770 channel_output_poll();
771 wait_until_can_do_something(&readset, &writeset, &max_fd,
776 channel_after_select(readset, writeset);
777 process_input(readset);
778 if (connection_closed)
780 process_output(writeset);
789 /* free all channels, no more reads and writes */
792 /* free remaining sessions, e.g. remove wtmp entries */
793 session_destroy_all(NULL);
797 server_input_channel_failure(int type, u_int32_t seq, void *ctxt)
799 debug("Got CHANNEL_FAILURE for keepalive");
801 * reset timeout, since we got a sane answer from the client.
802 * even if this was generated by something other than
803 * the bogus CHANNEL_REQUEST we send for keepalives.
805 client_alive_timeouts = 0;
810 server_input_stdin_data(int type, u_int32_t seq, void *ctxt)
815 /* Stdin data from the client. Append it to the buffer. */
816 /* Ignore any data if the client has closed stdin. */
819 data = packet_get_string(&data_len);
821 buffer_append(&stdin_buffer, data, data_len);
822 memset(data, 0, data_len);
827 server_input_eof(int type, u_int32_t seq, void *ctxt)
830 * Eof from the client. The stdin descriptor to the
831 * program will be closed when all buffered data has
834 debug("EOF received for stdin.");
840 server_input_window_size(int type, u_int32_t seq, void *ctxt)
842 int row = packet_get_int();
843 int col = packet_get_int();
844 int xpixel = packet_get_int();
845 int ypixel = packet_get_int();
847 debug("Window change received.");
850 pty_change_window_size(fdin, row, col, xpixel, ypixel);
854 server_request_direct_tcpip(char *ctype)
858 char *target, *originator;
859 int target_port, originator_port;
861 target = packet_get_string(NULL);
862 target_port = packet_get_int();
863 originator = packet_get_string(NULL);
864 originator_port = packet_get_int();
867 debug("server_request_direct_tcpip: originator %s port %d, target %s port %d",
868 originator, originator_port, target, target_port);
870 /* XXX check permission */
871 sock = channel_connect_to(target, target_port);
876 c = channel_new(ctype, SSH_CHANNEL_CONNECTING,
877 sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
878 CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("direct-tcpip"), 1);
883 server_request_session(char *ctype)
887 debug("input_session_request");
890 * A server session has no fd to read or write until a
891 * CHANNEL_REQUEST for a shell is made, so we set the type to
892 * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all
893 * CHANNEL_REQUEST messages is registered.
895 c = channel_new(ctype, SSH_CHANNEL_LARVAL,
896 -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT,
897 0, xstrdup("server-session"), 1);
898 if (session_open(xxx_authctxt, c->self) != 1) {
899 debug("session open failed, free channel %d", c->self);
903 channel_register_cleanup(c->self, session_close_by_channel);
908 server_input_channel_open(int type, u_int32_t seq, void *ctxt)
913 u_int rmaxpack, rwindow, len;
915 ctype = packet_get_string(&len);
916 rchan = packet_get_int();
917 rwindow = packet_get_int();
918 rmaxpack = packet_get_int();
920 debug("server_input_channel_open: ctype %s rchan %d win %d max %d",
921 ctype, rchan, rwindow, rmaxpack);
923 if (strcmp(ctype, "session") == 0) {
924 c = server_request_session(ctype);
925 } else if (strcmp(ctype, "direct-tcpip") == 0) {
926 c = server_request_direct_tcpip(ctype);
929 debug("server_input_channel_open: confirm %s", ctype);
930 c->remote_id = rchan;
931 c->remote_window = rwindow;
932 c->remote_maxpacket = rmaxpack;
933 if (c->type != SSH_CHANNEL_CONNECTING) {
934 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
935 packet_put_int(c->remote_id);
936 packet_put_int(c->self);
937 packet_put_int(c->local_window);
938 packet_put_int(c->local_maxpacket);
942 debug("server_input_channel_open: failure %s", ctype);
943 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
944 packet_put_int(rchan);
945 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
946 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
947 packet_put_cstring("open failed");
948 packet_put_cstring("");
956 server_input_global_request(int type, u_int32_t seq, void *ctxt)
962 rtype = packet_get_string(NULL);
963 want_reply = packet_get_char();
964 debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply);
966 /* -R style forwarding */
967 if (strcmp(rtype, "tcpip-forward") == 0) {
969 char *listen_address;
972 pw = auth_get_user();
974 fatal("server_input_global_request: no user");
975 listen_address = packet_get_string(NULL); /* XXX currently ignored */
976 listen_port = (u_short)packet_get_int();
977 debug("server_input_global_request: tcpip-forward listen %s port %d",
978 listen_address, listen_port);
980 /* check permissions */
981 if (!options.allow_tcp_forwarding ||
982 no_port_forwarding_flag
983 #ifndef NO_IPPORT_RESERVED_CONCEPT
984 || (listen_port < IPPORT_RESERVED && pw->pw_uid != 0)
988 packet_send_debug("Server has disabled port forwarding.");
990 /* Start listening on the port */
991 success = channel_setup_remote_fwd_listener(
992 listen_address, listen_port, options.gateway_ports);
994 xfree(listen_address);
997 packet_start(success ?
998 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1000 packet_write_wait();
1005 server_input_channel_req(int type, u_int32_t seq, void *ctxt)
1008 int id, reply, success = 0;
1011 id = packet_get_int();
1012 rtype = packet_get_string(NULL);
1013 reply = packet_get_char();
1015 debug("server_input_channel_req: channel %d request %s reply %d",
1018 if ((c = channel_lookup(id)) == NULL)
1019 packet_disconnect("server_input_channel_req: "
1020 "unknown channel %d", id);
1021 if (c->type == SSH_CHANNEL_LARVAL || c->type == SSH_CHANNEL_OPEN)
1022 success = session_input_channel_req(c, rtype);
1024 packet_start(success ?
1025 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1026 packet_put_int(c->remote_id);
1033 server_init_dispatch_20(void)
1035 debug("server_init_dispatch_20");
1036 dispatch_init(&dispatch_protocol_error);
1037 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1038 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1039 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1040 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1041 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open);
1042 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1043 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1044 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req);
1045 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1046 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request);
1048 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_channel_failure);
1050 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1053 server_init_dispatch_13(void)
1055 debug("server_init_dispatch_13");
1056 dispatch_init(NULL);
1057 dispatch_set(SSH_CMSG_EOF, &server_input_eof);
1058 dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
1059 dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
1060 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1061 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1062 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1063 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1064 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1065 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1068 server_init_dispatch_15(void)
1070 server_init_dispatch_13();
1071 debug("server_init_dispatch_15");
1072 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1073 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
1076 server_init_dispatch(void)
1079 server_init_dispatch_20();
1081 server_init_dispatch_13();
1083 server_init_dispatch_15();