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 $");
54 #include "auth-options.h"
55 #include "serverloop.h"
59 extern ServerOptions options;
63 static Authctxt *xxx_authctxt;
65 static Buffer stdin_buffer; /* Buffer for stdin data. */
66 static Buffer stdout_buffer; /* Buffer for stdout data. */
67 static Buffer stderr_buffer; /* Buffer for stderr data. */
68 static int fdin; /* Descriptor for stdin (for writing) */
69 static int fdout; /* Descriptor for stdout (for reading);
70 May be same number as fdin. */
71 static int fderr; /* Descriptor for stderr. May be -1. */
72 static long stdin_bytes = 0; /* Number of bytes written to stdin. */
73 static long stdout_bytes = 0; /* Number of stdout bytes sent to client. */
74 static long stderr_bytes = 0; /* Number of stderr bytes sent to client. */
75 static long fdout_bytes = 0; /* Number of stdout bytes read from program. */
76 static int stdin_eof = 0; /* EOF message received from client. */
77 static int fdout_eof = 0; /* EOF encountered reading from fdout. */
78 static int fderr_eof = 0; /* EOF encountered readung from fderr. */
79 static int fdin_is_tty = 0; /* fdin points to a tty. */
80 static int connection_in; /* Connection to client (input). */
81 static int connection_out; /* Connection to client (output). */
82 static int connection_closed = 0; /* Connection to client closed. */
83 static u_int buffer_high; /* "Soft" max buffer size. */
84 static int client_alive_timeouts = 0;
87 * This SIGCHLD kludge is used to detect when the child exits. The server
88 * will exit after that, as soon as forwarded connections have terminated.
91 static volatile sig_atomic_t child_terminated = 0; /* The child has terminated. */
94 static void server_init_dispatch(void);
97 * we write to this pipe if a SIGCHLD is caught in order to avoid
98 * the race between select() and child_terminated
100 static int notify_pipe[2];
104 if (pipe(notify_pipe) < 0) {
105 error("pipe(notify_pipe) failed %s", strerror(errno));
106 } else if ((fcntl(notify_pipe[0], F_SETFD, 1) == -1) ||
107 (fcntl(notify_pipe[1], F_SETFD, 1) == -1)) {
108 error("fcntl(notify_pipe, F_SETFD) failed %s", strerror(errno));
109 close(notify_pipe[0]);
110 close(notify_pipe[1]);
112 set_nonblock(notify_pipe[0]);
113 set_nonblock(notify_pipe[1]);
116 notify_pipe[0] = -1; /* read end */
117 notify_pipe[1] = -1; /* write end */
122 if (notify_pipe[1] != -1)
123 write(notify_pipe[1], "", 1);
126 notify_prepare(fd_set *readset)
128 if (notify_pipe[0] != -1)
129 FD_SET(notify_pipe[0], readset);
132 notify_done(fd_set *readset)
136 if (notify_pipe[0] != -1 && FD_ISSET(notify_pipe[0], readset))
137 while (read(notify_pipe[0], &c, 1) != -1)
138 debug2("notify_done: reading");
142 sigchld_handler(int sig)
144 int save_errno = errno;
145 debug("Received SIGCHLD.");
146 child_terminated = 1;
147 mysignal(SIGCHLD, sigchld_handler);
153 * Make packets from buffered stderr data, and buffer it for sending
157 make_packets_from_stderr_data(void)
161 /* Send buffered stderr data to the client. */
162 while (buffer_len(&stderr_buffer) > 0 &&
163 packet_not_very_much_data_to_write()) {
164 len = buffer_len(&stderr_buffer);
165 if (packet_is_interactive()) {
169 /* Keep the packets at reasonable size. */
170 if (len > packet_get_maxsize())
171 len = packet_get_maxsize();
173 packet_start(SSH_SMSG_STDERR_DATA);
174 packet_put_string(buffer_ptr(&stderr_buffer), len);
176 buffer_consume(&stderr_buffer, len);
182 * Make packets from buffered stdout data, and buffer it for sending to the
186 make_packets_from_stdout_data(void)
190 /* Send buffered stdout data to the client. */
191 while (buffer_len(&stdout_buffer) > 0 &&
192 packet_not_very_much_data_to_write()) {
193 len = buffer_len(&stdout_buffer);
194 if (packet_is_interactive()) {
198 /* Keep the packets at reasonable size. */
199 if (len > packet_get_maxsize())
200 len = packet_get_maxsize();
202 packet_start(SSH_SMSG_STDOUT_DATA);
203 packet_put_string(buffer_ptr(&stdout_buffer), len);
205 buffer_consume(&stdout_buffer, len);
211 client_alive_check(void)
213 static int had_channel = 0;
216 id = channel_find_open();
220 packet_disconnect("No open channels after timeout!");
224 /* timeout, check to see how many we have had */
225 if (++client_alive_timeouts > options.client_alive_count_max)
226 packet_disconnect("Timeout, your session not responding.");
229 * send a bogus channel request with "wantreply",
230 * we should get back a failure
232 channel_request_start(id, "keepalive@openssh.com", 1);
237 * Sleep in select() until we can do something. This will initialize the
238 * select masks. Upon return, the masks will indicate which descriptors
239 * have data or can accept data. Optionally, a maximum time can be specified
240 * for the duration of the wait (0 = infinite).
243 wait_until_can_do_something(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
244 int *nallocp, u_int max_time_milliseconds)
246 struct timeval tv, *tvp;
248 int client_alive_scheduled = 0;
251 * if using client_alive, set the max timeout accordingly,
252 * and indicate that this particular timeout was for client
253 * alive by setting the client_alive_scheduled flag.
255 * this could be randomized somewhat to make traffic
256 * analysis more difficult, but we're not doing it yet.
259 max_time_milliseconds == 0 && options.client_alive_interval) {
260 client_alive_scheduled = 1;
261 max_time_milliseconds = options.client_alive_interval * 1000;
264 /* Allocate and update select() masks for channel descriptors. */
265 channel_prepare_select(readsetp, writesetp, maxfdp, nallocp, 0);
269 /* wrong: bad condition XXX */
270 if (channel_not_very_much_buffered_data())
272 FD_SET(connection_in, *readsetp);
275 * Read packets from the client unless we have too much
276 * buffered stdin or channel data.
278 if (buffer_len(&stdin_buffer) < buffer_high &&
279 channel_not_very_much_buffered_data())
280 FD_SET(connection_in, *readsetp);
282 * If there is not too much data already buffered going to
283 * the client, try to get some more data from the program.
285 if (packet_not_very_much_data_to_write()) {
287 FD_SET(fdout, *readsetp);
289 FD_SET(fderr, *readsetp);
292 * If we have buffered data, try to write some of that data
295 if (fdin != -1 && buffer_len(&stdin_buffer) > 0)
296 FD_SET(fdin, *writesetp);
298 notify_prepare(*readsetp);
301 * If we have buffered packet data going to the client, mark that
304 if (packet_have_data_to_write())
305 FD_SET(connection_out, *writesetp);
308 * If child has terminated and there is enough buffer space to read
309 * from it, then read as much as is available and exit.
311 if (child_terminated && packet_not_very_much_data_to_write())
312 if (max_time_milliseconds == 0 || client_alive_scheduled)
313 max_time_milliseconds = 100;
315 if (max_time_milliseconds == 0)
318 tv.tv_sec = max_time_milliseconds / 1000;
319 tv.tv_usec = 1000 * (max_time_milliseconds % 1000);
323 /* Wait for something to happen, or the timeout to expire. */
324 ret = select((*maxfdp)+1, *readsetp, *writesetp, NULL, tvp);
327 memset(*readsetp, 0, *nallocp);
328 memset(*writesetp, 0, *nallocp);
330 error("select: %.100s", strerror(errno));
331 } else if (ret == 0 && client_alive_scheduled)
332 client_alive_check();
334 notify_done(*readsetp);
338 * Processes input from the client and the program. Input data is stored
339 * in buffers and processed later.
342 process_input(fd_set * readset)
347 /* Read and buffer any input data from the client. */
348 if (FD_ISSET(connection_in, readset)) {
349 len = read(connection_in, buf, sizeof(buf));
351 verbose("Connection closed by %.100s",
352 get_remote_ipaddr());
353 connection_closed = 1;
357 } else if (len < 0) {
358 if (errno != EINTR && errno != EAGAIN) {
359 verbose("Read error from remote host "
361 get_remote_ipaddr(), strerror(errno));
365 /* Buffer any received data. */
366 packet_process_incoming(buf, len);
372 /* Read and buffer any available stdout data from the program. */
373 if (!fdout_eof && FD_ISSET(fdout, readset)) {
374 len = read(fdout, buf, sizeof(buf));
375 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
377 } else if (len <= 0) {
380 buffer_append(&stdout_buffer, buf, len);
384 /* Read and buffer any available stderr data from the program. */
385 if (!fderr_eof && FD_ISSET(fderr, readset)) {
386 len = read(fderr, buf, sizeof(buf));
387 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
389 } else if (len <= 0) {
392 buffer_append(&stderr_buffer, buf, len);
398 * Sends data from internal buffers to client program stdin.
401 process_output(fd_set * writeset)
408 /* Write buffered data to program stdin. */
409 if (!compat20 && fdin != -1 && FD_ISSET(fdin, writeset)) {
410 data = buffer_ptr(&stdin_buffer);
411 dlen = buffer_len(&stdin_buffer);
412 len = write(fdin, data, dlen);
413 if (len < 0 && (errno == EINTR || errno == EAGAIN)) {
415 } else if (len <= 0) {
419 shutdown(fdin, SHUT_WR); /* We will no longer send. */
422 /* Successful write. */
423 if (fdin_is_tty && dlen >= 1 && data[0] != '\r' &&
424 tcgetattr(fdin, &tio) == 0 &&
425 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
427 * Simulate echo to reduce the impact of
430 packet_send_ignore(len);
433 /* Consume the data from the buffer. */
434 buffer_consume(&stdin_buffer, len);
435 /* Update the count of bytes written to the program. */
439 /* Send any buffered packet data to the client. */
440 if (FD_ISSET(connection_out, writeset))
445 * Wait until all buffered output has been sent to the client.
446 * This is used when the program terminates.
451 /* Send any buffered stdout data to the client. */
452 if (buffer_len(&stdout_buffer) > 0) {
453 packet_start(SSH_SMSG_STDOUT_DATA);
454 packet_put_string(buffer_ptr(&stdout_buffer),
455 buffer_len(&stdout_buffer));
457 /* Update the count of sent bytes. */
458 stdout_bytes += buffer_len(&stdout_buffer);
460 /* Send any buffered stderr data to the client. */
461 if (buffer_len(&stderr_buffer) > 0) {
462 packet_start(SSH_SMSG_STDERR_DATA);
463 packet_put_string(buffer_ptr(&stderr_buffer),
464 buffer_len(&stderr_buffer));
466 /* Update the count of sent bytes. */
467 stderr_bytes += buffer_len(&stderr_buffer);
469 /* Wait until all buffered data has been written to the client. */
474 process_buffered_input_packets(void)
476 dispatch_run(DISPATCH_NONBLOCK, NULL, compat20 ? xxx_kex : NULL);
480 * Performs the interactive session. This handles data transmission between
481 * the client and the program. Note that the notion of stdin, stdout, and
482 * stderr in this function is sort of reversed: this function writes to
483 * stdin (of the child program), and reads from stdout and stderr (of the
487 server_loop(pid_t pid, int fdin_arg, int fdout_arg, int fderr_arg)
489 fd_set *readset = NULL, *writeset = NULL;
490 int max_fd = 0, nalloc = 0;
491 int wait_status; /* Status returned by wait(). */
492 pid_t wait_pid; /* pid returned by wait(). */
493 int waiting_termination = 0; /* Have displayed waiting close message. */
494 u_int max_time_milliseconds;
495 u_int previous_stdout_buffer_bytes;
496 u_int stdout_buffer_bytes;
499 debug("Entering interactive session.");
501 /* Initialize the SIGCHLD kludge. */
502 child_terminated = 0;
503 mysignal(SIGCHLD, sigchld_handler);
505 /* Initialize our global variables. */
513 /* we don't have stderr for interactive terminal sessions, see below */
517 if (!(datafellows & SSH_BUG_IGNOREMSG) && isatty(fdin))
520 connection_in = packet_get_connection_in();
521 connection_out = packet_get_connection_out();
525 previous_stdout_buffer_bytes = 0;
527 /* Set approximate I/O buffer size. */
528 if (packet_is_interactive())
531 buffer_high = 64 * 1024;
534 /* Initialize max_fd to the maximum of the known file descriptors. */
535 max_fd = MAX(connection_in, connection_out);
536 max_fd = MAX(max_fd, fdin);
537 max_fd = MAX(max_fd, fdout);
539 max_fd = MAX(max_fd, fderr);
542 /* Initialize Initialize buffers. */
543 buffer_init(&stdin_buffer);
544 buffer_init(&stdout_buffer);
545 buffer_init(&stderr_buffer);
548 * If we have no separate fderr (which is the case when we have a pty
549 * - there we cannot make difference between data sent to stdout and
550 * stderr), indicate that we have seen an EOF from stderr. This way
551 * we don\'t need to check the descriptor everywhere.
556 server_init_dispatch();
558 /* Main loop of the server for the interactive session mode. */
561 /* Process buffered packets from the client. */
562 process_buffered_input_packets();
565 * If we have received eof, and there is no more pending
566 * input data, cause a real eof by closing fdin.
568 if (stdin_eof && fdin != -1 && buffer_len(&stdin_buffer) == 0) {
572 shutdown(fdin, SHUT_WR); /* We will no longer send. */
575 /* Make packets from buffered stderr data to send to the client. */
576 make_packets_from_stderr_data();
579 * Make packets from buffered stdout data to send to the
580 * client. If there is very little to send, this arranges to
581 * not send them now, but to wait a short while to see if we
582 * are getting more data. This is necessary, as some systems
583 * wake up readers from a pty after each separate character.
585 max_time_milliseconds = 0;
586 stdout_buffer_bytes = buffer_len(&stdout_buffer);
587 if (stdout_buffer_bytes != 0 && stdout_buffer_bytes < 256 &&
588 stdout_buffer_bytes != previous_stdout_buffer_bytes) {
589 /* try again after a while */
590 max_time_milliseconds = 10;
593 make_packets_from_stdout_data();
595 previous_stdout_buffer_bytes = buffer_len(&stdout_buffer);
597 /* Send channel data to the client. */
598 if (packet_not_very_much_data_to_write())
599 channel_output_poll();
602 * Bail out of the loop if the program has closed its output
603 * descriptors, and we have no more data to send to the
604 * client, and there is no pending buffered data.
606 if (fdout_eof && fderr_eof && !packet_have_data_to_write() &&
607 buffer_len(&stdout_buffer) == 0 && buffer_len(&stderr_buffer) == 0) {
608 if (!channel_still_open())
610 if (!waiting_termination) {
611 const char *s = "Waiting for forwarded connections to terminate...\r\n";
613 waiting_termination = 1;
614 buffer_append(&stderr_buffer, s, strlen(s));
616 /* Display list of open channels. */
617 cp = channel_open_message();
618 buffer_append(&stderr_buffer, cp, strlen(cp));
622 max_fd = MAX(connection_in, connection_out);
623 max_fd = MAX(max_fd, fdin);
624 max_fd = MAX(max_fd, fdout);
625 max_fd = MAX(max_fd, fderr);
626 max_fd = MAX(max_fd, notify_pipe[0]);
628 /* Sleep in select() until we can do something. */
629 wait_until_can_do_something(&readset, &writeset, &max_fd,
630 &nalloc, max_time_milliseconds);
632 /* Process any channel events. */
633 channel_after_select(readset, writeset);
635 /* Process input from the client and from program stdout/stderr. */
636 process_input(readset);
638 /* Process output to the client and to program stdin. */
639 process_output(writeset);
646 /* Cleanup and termination code. */
648 /* Wait until all output has been sent to the client. */
651 debug("End of interactive session; stdin %ld, stdout (read %ld, sent %ld), stderr %ld bytes.",
652 stdin_bytes, fdout_bytes, stdout_bytes, stderr_bytes);
654 /* Free and clear the buffers. */
655 buffer_free(&stdin_buffer);
656 buffer_free(&stdout_buffer);
657 buffer_free(&stderr_buffer);
659 /* Close the file descriptors. */
674 /* We no longer want our SIGCHLD handler to be called. */
675 mysignal(SIGCHLD, SIG_DFL);
677 while ((wait_pid = waitpid(-1, &wait_status, 0)) < 0)
679 packet_disconnect("wait: %.100s", strerror(errno));
681 error("Strange, wait returned pid %ld, expected %ld",
682 (long)wait_pid, (long)pid);
684 /* Check if it exited normally. */
685 if (WIFEXITED(wait_status)) {
686 /* Yes, normal exit. Get exit status and send it to the client. */
687 debug("Command exited with status %d.", WEXITSTATUS(wait_status));
688 packet_start(SSH_SMSG_EXITSTATUS);
689 packet_put_int(WEXITSTATUS(wait_status));
694 * Wait for exit confirmation. Note that there might be
695 * other packets coming before it; however, the program has
696 * already died so we just ignore them. The client is
697 * supposed to respond with the confirmation when it receives
701 type = packet_read();
703 while (type != SSH_CMSG_EXIT_CONFIRMATION);
705 debug("Received exit confirmation.");
708 /* Check if the program terminated due to a signal. */
709 if (WIFSIGNALED(wait_status))
710 packet_disconnect("Command terminated on signal %d.",
711 WTERMSIG(wait_status));
713 /* Some weird exit cause. Just exit. */
714 packet_disconnect("wait returned status %04x.", wait_status);
719 collect_children(void)
725 /* block SIGCHLD while we check for dead children */
727 sigaddset(&nset, SIGCHLD);
728 sigprocmask(SIG_BLOCK, &nset, &oset);
729 if (child_terminated) {
730 while ((pid = waitpid(-1, &status, WNOHANG)) > 0 ||
731 (pid < 0 && errno == EINTR))
733 session_close_by_pid(pid, status);
734 child_terminated = 0;
736 sigprocmask(SIG_SETMASK, &oset, NULL);
740 server_loop2(Authctxt *authctxt)
742 fd_set *readset = NULL, *writeset = NULL;
743 int rekeying = 0, max_fd, nalloc = 0;
745 debug("Entering interactive session for SSH2.");
747 mysignal(SIGCHLD, sigchld_handler);
748 child_terminated = 0;
749 connection_in = packet_get_connection_in();
750 connection_out = packet_get_connection_out();
754 max_fd = MAX(connection_in, connection_out);
755 max_fd = MAX(max_fd, notify_pipe[0]);
757 xxx_authctxt = authctxt;
759 server_init_dispatch();
762 process_buffered_input_packets();
764 rekeying = (xxx_kex != NULL && !xxx_kex->done);
766 if (!rekeying && packet_not_very_much_data_to_write())
767 channel_output_poll();
768 wait_until_can_do_something(&readset, &writeset, &max_fd,
773 channel_after_select(readset, writeset);
774 process_input(readset);
775 if (connection_closed)
777 process_output(writeset);
786 /* free all channels, no more reads and writes */
789 /* free remaining sessions, e.g. remove wtmp entries */
790 session_destroy_all(NULL);
794 server_input_channel_failure(int type, u_int32_t seq, void *ctxt)
796 debug("Got CHANNEL_FAILURE for keepalive");
798 * reset timeout, since we got a sane answer from the client.
799 * even if this was generated by something other than
800 * the bogus CHANNEL_REQUEST we send for keepalives.
802 client_alive_timeouts = 0;
807 server_input_stdin_data(int type, u_int32_t seq, void *ctxt)
812 /* Stdin data from the client. Append it to the buffer. */
813 /* Ignore any data if the client has closed stdin. */
816 data = packet_get_string(&data_len);
818 buffer_append(&stdin_buffer, data, data_len);
819 memset(data, 0, data_len);
824 server_input_eof(int type, u_int32_t seq, void *ctxt)
827 * Eof from the client. The stdin descriptor to the
828 * program will be closed when all buffered data has
831 debug("EOF received for stdin.");
837 server_input_window_size(int type, u_int32_t seq, void *ctxt)
839 int row = packet_get_int();
840 int col = packet_get_int();
841 int xpixel = packet_get_int();
842 int ypixel = packet_get_int();
844 debug("Window change received.");
847 pty_change_window_size(fdin, row, col, xpixel, ypixel);
851 server_request_direct_tcpip(char *ctype)
855 char *target, *originator;
856 int target_port, originator_port;
858 target = packet_get_string(NULL);
859 target_port = packet_get_int();
860 originator = packet_get_string(NULL);
861 originator_port = packet_get_int();
864 debug("server_request_direct_tcpip: originator %s port %d, target %s port %d",
865 originator, originator_port, target, target_port);
867 /* XXX check permission */
868 sock = channel_connect_to(target, target_port);
873 c = channel_new(ctype, SSH_CHANNEL_CONNECTING,
874 sock, sock, -1, CHAN_TCP_WINDOW_DEFAULT,
875 CHAN_TCP_PACKET_DEFAULT, 0, xstrdup("direct-tcpip"), 1);
880 server_request_session(char *ctype)
884 debug("input_session_request");
887 * A server session has no fd to read or write until a
888 * CHANNEL_REQUEST for a shell is made, so we set the type to
889 * SSH_CHANNEL_LARVAL. Additionally, a callback for handling all
890 * CHANNEL_REQUEST messages is registered.
892 c = channel_new(ctype, SSH_CHANNEL_LARVAL,
893 -1, -1, -1, /*window size*/0, CHAN_SES_PACKET_DEFAULT,
894 0, xstrdup("server-session"), 1);
895 if (session_open(xxx_authctxt, c->self) != 1) {
896 debug("session open failed, free channel %d", c->self);
900 channel_register_cleanup(c->self, session_close_by_channel);
905 server_input_channel_open(int type, u_int32_t seq, void *ctxt)
910 u_int rmaxpack, rwindow, len;
912 ctype = packet_get_string(&len);
913 rchan = packet_get_int();
914 rwindow = packet_get_int();
915 rmaxpack = packet_get_int();
917 debug("server_input_channel_open: ctype %s rchan %d win %d max %d",
918 ctype, rchan, rwindow, rmaxpack);
920 if (strcmp(ctype, "session") == 0) {
921 c = server_request_session(ctype);
922 } else if (strcmp(ctype, "direct-tcpip") == 0) {
923 c = server_request_direct_tcpip(ctype);
926 debug("server_input_channel_open: confirm %s", ctype);
927 c->remote_id = rchan;
928 c->remote_window = rwindow;
929 c->remote_maxpacket = rmaxpack;
930 if (c->type != SSH_CHANNEL_CONNECTING) {
931 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION);
932 packet_put_int(c->remote_id);
933 packet_put_int(c->self);
934 packet_put_int(c->local_window);
935 packet_put_int(c->local_maxpacket);
939 debug("server_input_channel_open: failure %s", ctype);
940 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE);
941 packet_put_int(rchan);
942 packet_put_int(SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED);
943 if (!(datafellows & SSH_BUG_OPENFAILURE)) {
944 packet_put_cstring("open failed");
945 packet_put_cstring("");
953 server_input_global_request(int type, u_int32_t seq, void *ctxt)
959 rtype = packet_get_string(NULL);
960 want_reply = packet_get_char();
961 debug("server_input_global_request: rtype %s want_reply %d", rtype, want_reply);
963 /* -R style forwarding */
964 if (strcmp(rtype, "tcpip-forward") == 0) {
966 char *listen_address;
969 pw = auth_get_user();
971 fatal("server_input_global_request: no user");
972 listen_address = packet_get_string(NULL); /* XXX currently ignored */
973 listen_port = (u_short)packet_get_int();
974 debug("server_input_global_request: tcpip-forward listen %s port %d",
975 listen_address, listen_port);
977 /* check permissions */
978 if (!options.allow_tcp_forwarding ||
979 no_port_forwarding_flag
980 #ifndef NO_IPPORT_RESERVED_CONCEPT
981 || (listen_port < IPPORT_RESERVED && pw->pw_uid != 0)
985 packet_send_debug("Server has disabled port forwarding.");
987 /* Start listening on the port */
988 success = channel_setup_remote_fwd_listener(
989 listen_address, listen_port, options.gateway_ports);
991 xfree(listen_address);
994 packet_start(success ?
995 SSH2_MSG_REQUEST_SUCCESS : SSH2_MSG_REQUEST_FAILURE);
1002 server_input_channel_req(int type, u_int32_t seq, void *ctxt)
1005 int id, reply, success = 0;
1008 id = packet_get_int();
1009 rtype = packet_get_string(NULL);
1010 reply = packet_get_char();
1012 debug("server_input_channel_req: channel %d request %s reply %d",
1015 if ((c = channel_lookup(id)) == NULL)
1016 packet_disconnect("server_input_channel_req: "
1017 "unknown channel %d", id);
1018 if (c->type == SSH_CHANNEL_LARVAL || c->type == SSH_CHANNEL_OPEN)
1019 success = session_input_channel_req(c, rtype);
1021 packet_start(success ?
1022 SSH2_MSG_CHANNEL_SUCCESS : SSH2_MSG_CHANNEL_FAILURE);
1023 packet_put_int(c->remote_id);
1030 server_init_dispatch_20(void)
1032 debug("server_init_dispatch_20");
1033 dispatch_init(&dispatch_protocol_error);
1034 dispatch_set(SSH2_MSG_CHANNEL_CLOSE, &channel_input_oclose);
1035 dispatch_set(SSH2_MSG_CHANNEL_DATA, &channel_input_data);
1036 dispatch_set(SSH2_MSG_CHANNEL_EOF, &channel_input_ieof);
1037 dispatch_set(SSH2_MSG_CHANNEL_EXTENDED_DATA, &channel_input_extended_data);
1038 dispatch_set(SSH2_MSG_CHANNEL_OPEN, &server_input_channel_open);
1039 dispatch_set(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1040 dispatch_set(SSH2_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1041 dispatch_set(SSH2_MSG_CHANNEL_REQUEST, &server_input_channel_req);
1042 dispatch_set(SSH2_MSG_CHANNEL_WINDOW_ADJUST, &channel_input_window_adjust);
1043 dispatch_set(SSH2_MSG_GLOBAL_REQUEST, &server_input_global_request);
1045 dispatch_set(SSH2_MSG_CHANNEL_FAILURE, &server_input_channel_failure);
1047 dispatch_set(SSH2_MSG_KEXINIT, &kex_input_kexinit);
1050 server_init_dispatch_13(void)
1052 debug("server_init_dispatch_13");
1053 dispatch_init(NULL);
1054 dispatch_set(SSH_CMSG_EOF, &server_input_eof);
1055 dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
1056 dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
1057 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
1058 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
1059 dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
1060 dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
1061 dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
1062 dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
1065 server_init_dispatch_15(void)
1067 server_init_dispatch_13();
1068 debug("server_init_dispatch_15");
1069 dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
1070 dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
1073 server_init_dispatch(void)
1076 server_init_dispatch_20();
1078 server_init_dispatch_13();
1080 server_init_dispatch_15();