2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * This file contains functions for generic socket connection forwarding.
6 * There is also code for initiating connection forwarding for X11 connections,
7 * arbitrary tcp/ip connections, and the authentication agent connection.
9 * As far as I am concerned, the code I have written for this software
10 * can be used freely for any purpose. Any derived versions of this
11 * software must be clearly marked as such, and if the derived work is
12 * incompatible with the protocol description in the RFC file, it must be
13 * called by a name other than "ssh" or "Secure Shell".
16 * SSH2 support added by Markus Friedl.
17 * Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
18 * Copyright (c) 1999 Dug Song. All rights reserved.
19 * Copyright (c) 1999 Theo de Raadt. All rights reserved.
21 * Redistribution and use in source and binary forms, with or without
22 * modification, are permitted provided that the following conditions
24 * 1. Redistributions of source code must retain the above copyright
25 * notice, this list of conditions and the following disclaimer.
26 * 2. Redistributions in binary form must reproduce the above copyright
27 * notice, this list of conditions and the following disclaimer in the
28 * documentation and/or other materials provided with the distribution.
30 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
31 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
32 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
33 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
34 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
35 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
39 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43 RCSID("$OpenBSD: channels.c,v 1.99 2001/03/16 19:06:29 markus Exp $");
45 #include <openssl/rsa.h>
46 #include <openssl/dsa.h>
64 /* Maximum number of fake X11 displays to try. */
65 #define MAX_DISPLAYS 1000
67 /* Max len of agent socket */
68 #define MAX_SOCKET_NAME 100
71 * Pointer to an array containing all allocated channels. The array is
72 * dynamically extended as needed.
74 static Channel *channels = NULL;
77 * Size of the channel array. All slots of the array must always be
78 * initialized (at least the type field); unused slots are marked with type
81 static int channels_alloc = 0;
84 * Maximum file descriptor value used in any of the channels. This is
85 * updated in channel_allocate.
87 static int channel_max_fd = 0;
89 /* Name and directory of socket for authentication agent forwarding. */
90 static char *channel_forwarded_auth_socket_name = NULL;
91 static char *channel_forwarded_auth_socket_dir = NULL;
93 /* Saved X11 authentication protocol name. */
94 char *x11_saved_proto = NULL;
96 /* Saved X11 authentication data. This is the real data. */
97 char *x11_saved_data = NULL;
98 u_int x11_saved_data_len = 0;
101 * Fake X11 authentication data. This is what the server will be sending us;
102 * we should replace any occurrences of this by the real data.
104 char *x11_fake_data = NULL;
105 u_int x11_fake_data_len;
108 * Data structure for storing which hosts are permitted for forward requests.
109 * The local sides of any remote forwards are stored in this array to prevent
110 * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
111 * network (which might be behind a firewall).
114 char *host_to_connect; /* Connect to 'host'. */
115 u_short port_to_connect; /* Connect to 'port'. */
116 u_short listen_port; /* Remote side should listen port number. */
119 /* List of all permitted host/port pairs to connect. */
120 static ForwardPermission permitted_opens[SSH_MAX_FORWARDS_PER_DIRECTION];
121 /* Number of permitted host/port pairs in the array. */
122 static int num_permitted_opens = 0;
124 * If this is true, all opens are permitted. This is the case on the server
125 * on which we have to trust the client anyway, and the user could do
126 * anything after logging in anyway.
128 static int all_opens_permitted = 0;
130 /* This is set to true if both sides support SSH_PROTOFLAG_HOST_IN_FWD_OPEN. */
131 static int have_hostname_in_open = 0;
133 /* AF_UNSPEC or AF_INET or AF_INET6 */
136 /* Sets specific protocol options. */
139 channel_set_options(int hostname_in_open)
141 have_hostname_in_open = hostname_in_open;
144 /* lookup channel by id */
147 channel_lookup(int id)
150 if (id < 0 || id > channels_alloc) {
151 log("channel_lookup: %d: bad id", id);
155 if (c->type == SSH_CHANNEL_FREE) {
156 log("channel_lookup: %d: bad id: channel free", id);
163 * Register filedescriptors for a channel, used when allocating a channel or
164 * when the channel consumer/producer is ready, e.g. shell exec'd
168 channel_register_fds(Channel *c, int rfd, int wfd, int efd,
169 int extusage, int nonblock)
171 /* Update the maximum file descriptor value. */
172 channel_max_fd = MAX(channel_max_fd, rfd);
173 channel_max_fd = MAX(channel_max_fd, wfd);
174 channel_max_fd = MAX(channel_max_fd, efd);
176 /* XXX set close-on-exec -markus */
180 c->sock = (rfd == wfd) ? rfd : -1;
182 c->extended_usage = extusage;
184 /* XXX ugly hack: nonblock is only set by the server */
185 if (nonblock && isatty(c->rfd)) {
186 debug("channel %d: rfd %d isatty", c->self, c->rfd);
188 if (!isatty(c->wfd)) {
189 error("channel %d: wfd %d is not a tty?",
196 /* enable nonblocking mode */
208 * Allocate a new channel object and set its type and socket. This will cause
209 * remote_name to be freed.
213 channel_new(char *ctype, int type, int rfd, int wfd, int efd,
214 int window, int maxpack, int extusage, char *remote_name, int nonblock)
219 /* Do initial allocation if this is the first call. */
220 if (channels_alloc == 0) {
223 channels = xmalloc(channels_alloc * sizeof(Channel));
224 for (i = 0; i < channels_alloc; i++)
225 channels[i].type = SSH_CHANNEL_FREE;
227 * Kludge: arrange a call to channel_stop_listening if we
228 * terminate with fatal().
230 fatal_add_cleanup((void (*) (void *)) channel_stop_listening, NULL);
232 /* Try to find a free slot where to put the new channel. */
233 for (found = -1, i = 0; i < channels_alloc; i++)
234 if (channels[i].type == SSH_CHANNEL_FREE) {
235 /* Found a free slot. */
240 /* There are no free slots. Take last+1 slot and expand the array. */
241 found = channels_alloc;
242 channels_alloc += 10;
243 debug2("channel: expanding %d", channels_alloc);
244 channels = xrealloc(channels, channels_alloc * sizeof(Channel));
245 for (i = found; i < channels_alloc; i++)
246 channels[i].type = SSH_CHANNEL_FREE;
248 /* Initialize and return new channel number. */
249 c = &channels[found];
250 buffer_init(&c->input);
251 buffer_init(&c->output);
252 buffer_init(&c->extended);
253 chan_init_iostates(c);
254 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
258 c->local_window = window;
259 c->local_window_max = window;
260 c->local_consumed = 0;
261 c->local_maxpacket = maxpack;
263 c->remote_name = remote_name;
264 c->remote_window = 0;
265 c->remote_maxpacket = 0;
269 c->dettach_user = NULL;
270 c->input_filter = NULL;
271 debug("channel %d: new [%s]", found, remote_name);
274 /* old interface XXX */
276 channel_allocate(int type, int sock, char *remote_name)
278 return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name, 1);
282 /* Close all channel fd/socket. */
285 channel_close_fds(Channel *c)
305 /* Free the channel and close its fd/socket. */
310 Channel *c = channel_lookup(id);
311 char *s = channel_open_message();
314 packet_disconnect("channel free: bad local channel %d", id);
315 debug("channel_free: channel %d: status: %s", id, s);
318 if (c->dettach_user != NULL) {
319 debug("channel_free: channel %d: dettaching channel user", id);
320 c->dettach_user(c->self, NULL);
323 shutdown(c->sock, SHUT_RDWR);
324 channel_close_fds(c);
325 buffer_free(&c->input);
326 buffer_free(&c->output);
327 buffer_free(&c->extended);
328 c->type = SSH_CHANNEL_FREE;
329 if (c->remote_name) {
330 xfree(c->remote_name);
331 c->remote_name = NULL;
336 * 'channel_pre*' are called just before select() to add any bits relevant to
337 * channels in the select bitmasks.
340 * 'channel_post*': perform any appropriate operations for channels which
341 * have events pending.
343 typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
344 chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
345 chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
348 channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
350 FD_SET(c->sock, readset);
354 channel_pre_connecting(Channel *c, fd_set * readset, fd_set * writeset)
356 debug3("channel %d: waiting for connection", c->self);
357 FD_SET(c->sock, writeset);
361 channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
363 if (buffer_len(&c->input) < packet_get_maxsize())
364 FD_SET(c->sock, readset);
365 if (buffer_len(&c->output) > 0)
366 FD_SET(c->sock, writeset);
370 channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
372 /* test whether sockets are 'alive' for read/write */
373 if (c->istate == CHAN_INPUT_OPEN)
374 if (buffer_len(&c->input) < packet_get_maxsize())
375 FD_SET(c->sock, readset);
376 if (c->ostate == CHAN_OUTPUT_OPEN ||
377 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
378 if (buffer_len(&c->output) > 0) {
379 FD_SET(c->sock, writeset);
380 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
387 channel_pre_open_20(Channel *c, fd_set * readset, fd_set * writeset)
389 if (c->istate == CHAN_INPUT_OPEN &&
390 c->remote_window > 0 &&
391 buffer_len(&c->input) < c->remote_window)
392 FD_SET(c->rfd, readset);
393 if (c->ostate == CHAN_OUTPUT_OPEN ||
394 c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
395 if (buffer_len(&c->output) > 0) {
396 FD_SET(c->wfd, writeset);
397 } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
401 /** XXX check close conditions, too */
403 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
404 buffer_len(&c->extended) > 0)
405 FD_SET(c->efd, writeset);
406 else if (c->extended_usage == CHAN_EXTENDED_READ &&
407 buffer_len(&c->extended) < c->remote_window)
408 FD_SET(c->efd, readset);
413 channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
415 if (buffer_len(&c->input) == 0) {
416 packet_start(SSH_MSG_CHANNEL_CLOSE);
417 packet_put_int(c->remote_id);
419 c->type = SSH_CHANNEL_CLOSED;
420 debug("Closing channel %d after input drain.", c->self);
425 channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
427 if (buffer_len(&c->output) == 0)
428 channel_free(c->self);
430 FD_SET(c->sock, writeset);
434 * This is a special state for X11 authentication spoofing. An opened X11
435 * connection (when authentication spoofing is being done) remains in this
436 * state until the first packet has been completely read. The authentication
437 * data in that packet is then substituted by the real data if it matches the
438 * fake data, and the channel is put into normal mode.
439 * XXX All this happens at the client side.
442 x11_open_helper(Channel *c)
445 u_int proto_len, data_len;
447 /* Check if the fixed size part of the packet is in buffer. */
448 if (buffer_len(&c->output) < 12)
451 /* Parse the lengths of variable-length fields. */
452 ucp = (u_char *) buffer_ptr(&c->output);
453 if (ucp[0] == 0x42) { /* Byte order MSB first. */
454 proto_len = 256 * ucp[6] + ucp[7];
455 data_len = 256 * ucp[8] + ucp[9];
456 } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
457 proto_len = ucp[6] + 256 * ucp[7];
458 data_len = ucp[8] + 256 * ucp[9];
460 debug("Initial X11 packet contains bad byte order byte: 0x%x",
465 /* Check if the whole packet is in buffer. */
466 if (buffer_len(&c->output) <
467 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
470 /* Check if authentication protocol matches. */
471 if (proto_len != strlen(x11_saved_proto) ||
472 memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
473 debug("X11 connection uses different authentication protocol.");
476 /* Check if authentication data matches our fake data. */
477 if (data_len != x11_fake_data_len ||
478 memcmp(ucp + 12 + ((proto_len + 3) & ~3),
479 x11_fake_data, x11_fake_data_len) != 0) {
480 debug("X11 auth data does not match fake data.");
483 /* Check fake data length */
484 if (x11_fake_data_len != x11_saved_data_len) {
485 error("X11 fake_data_len %d != saved_data_len %d",
486 x11_fake_data_len, x11_saved_data_len);
490 * Received authentication protocol and data match
491 * our fake data. Substitute the fake data with real
494 memcpy(ucp + 12 + ((proto_len + 3) & ~3),
495 x11_saved_data, x11_saved_data_len);
500 channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
502 int ret = x11_open_helper(c);
504 /* Start normal processing for the channel. */
505 c->type = SSH_CHANNEL_OPEN;
506 channel_pre_open_13(c, readset, writeset);
507 } else if (ret == -1) {
509 * We have received an X11 connection that has bad
510 * authentication information.
512 log("X11 connection rejected because of wrong authentication.");
513 buffer_clear(&c->input);
514 buffer_clear(&c->output);
517 c->type = SSH_CHANNEL_CLOSED;
518 packet_start(SSH_MSG_CHANNEL_CLOSE);
519 packet_put_int(c->remote_id);
525 channel_pre_x11_open(Channel *c, fd_set * readset, fd_set * writeset)
527 int ret = x11_open_helper(c);
529 c->type = SSH_CHANNEL_OPEN;
531 channel_pre_open_20(c, readset, writeset);
533 channel_pre_open_15(c, readset, writeset);
534 } else if (ret == -1) {
535 debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
536 chan_read_failed(c); /** force close? */
537 chan_write_failed(c);
538 debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
542 /* This is our fake X11 server socket. */
544 channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
546 struct sockaddr addr;
549 char buf[16384], *remote_ipaddr;
552 if (FD_ISSET(c->sock, readset)) {
553 debug("X11 connection requested.");
554 addrlen = sizeof(addr);
555 newsock = accept(c->sock, &addr, &addrlen);
557 error("accept: %.100s", strerror(errno));
560 remote_ipaddr = get_peer_ipaddr(newsock);
561 remote_port = get_peer_port(newsock);
562 snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
563 remote_ipaddr, remote_port);
565 newch = channel_new("x11",
566 SSH_CHANNEL_OPENING, newsock, newsock, -1,
567 c->local_window_max, c->local_maxpacket,
570 packet_start(SSH2_MSG_CHANNEL_OPEN);
571 packet_put_cstring("x11");
572 packet_put_int(newch);
573 packet_put_int(c->local_window_max);
574 packet_put_int(c->local_maxpacket);
575 /* originator ipaddr and port */
576 packet_put_cstring(remote_ipaddr);
577 if (datafellows & SSH_BUG_X11FWD) {
578 debug("ssh2 x11 bug compat mode");
580 packet_put_int(remote_port);
584 packet_start(SSH_SMSG_X11_OPEN);
585 packet_put_int(newch);
586 if (have_hostname_in_open)
587 packet_put_string(buf, strlen(buf));
590 xfree(remote_ipaddr);
595 * This socket is listening for connections to a forwarded TCP/IP port.
598 channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
600 struct sockaddr addr;
603 char buf[1024], *remote_ipaddr, *rtype;
606 rtype = (c->type == SSH_CHANNEL_RPORT_LISTENER) ?
607 "forwarded-tcpip" : "direct-tcpip";
609 if (FD_ISSET(c->sock, readset)) {
610 debug("Connection to port %d forwarding "
611 "to %.100s port %d requested.",
612 c->listening_port, c->path, c->host_port);
613 addrlen = sizeof(addr);
614 newsock = accept(c->sock, &addr, &addrlen);
616 error("accept: %.100s", strerror(errno));
619 remote_ipaddr = get_peer_ipaddr(newsock);
620 remote_port = get_peer_port(newsock);
621 snprintf(buf, sizeof buf,
622 "listen port %d for %.100s port %d, "
623 "connect from %.200s port %d",
624 c->listening_port, c->path, c->host_port,
625 remote_ipaddr, remote_port);
627 newch = channel_new(rtype,
628 SSH_CHANNEL_OPENING, newsock, newsock, -1,
629 c->local_window_max, c->local_maxpacket,
632 packet_start(SSH2_MSG_CHANNEL_OPEN);
633 packet_put_cstring(rtype);
634 packet_put_int(newch);
635 packet_put_int(c->local_window_max);
636 packet_put_int(c->local_maxpacket);
637 if (c->type == SSH_CHANNEL_RPORT_LISTENER) {
638 /* listen address, port */
639 packet_put_string(c->path, strlen(c->path));
640 packet_put_int(c->listening_port);
642 /* target host, port */
643 packet_put_string(c->path, strlen(c->path));
644 packet_put_int(c->host_port);
646 /* originator host and port */
647 packet_put_cstring(remote_ipaddr);
648 packet_put_int(remote_port);
651 packet_start(SSH_MSG_PORT_OPEN);
652 packet_put_int(newch);
653 packet_put_string(c->path, strlen(c->path));
654 packet_put_int(c->host_port);
655 if (have_hostname_in_open) {
656 packet_put_string(buf, strlen(buf));
660 xfree(remote_ipaddr);
665 * This is the authentication agent socket listening for connections from
669 channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
671 struct sockaddr addr;
675 if (FD_ISSET(c->sock, readset)) {
676 addrlen = sizeof(addr);
677 newsock = accept(c->sock, &addr, &addrlen);
679 error("accept from auth socket: %.100s", strerror(errno));
682 newch = channel_new("accepted auth socket",
683 SSH_CHANNEL_OPENING, newsock, newsock, -1,
684 c->local_window_max, c->local_maxpacket,
685 0, xstrdup("accepted auth socket"), 1);
687 packet_start(SSH2_MSG_CHANNEL_OPEN);
688 packet_put_cstring("auth-agent@openssh.com");
689 packet_put_int(newch);
690 packet_put_int(c->local_window_max);
691 packet_put_int(c->local_maxpacket);
693 packet_start(SSH_SMSG_AGENT_OPEN);
694 packet_put_int(newch);
701 channel_post_connecting(Channel *c, fd_set * readset, fd_set * writeset)
703 if (FD_ISSET(c->sock, writeset)) {
705 int sz = sizeof(err);
706 c->type = SSH_CHANNEL_OPEN;
707 if (getsockopt(c->sock, SOL_SOCKET, SO_ERROR, (char *)&err, &sz) < 0) {
708 debug("getsockopt SO_ERROR failed");
711 debug("channel %d: connected)", c->self);
713 debug("channel %d: not connected: %s",
714 c->self, strerror(err));
716 chan_write_failed(c);
723 channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
729 FD_ISSET(c->rfd, readset)) {
730 len = read(c->rfd, buf, sizeof(buf));
731 if (len < 0 && (errno == EINTR || errno == EAGAIN))
734 debug("channel %d: read<=0 rfd %d len %d",
735 c->self, c->rfd, len);
737 buffer_consume(&c->output, buffer_len(&c->output));
738 c->type = SSH_CHANNEL_INPUT_DRAINING;
739 debug("Channel %d status set to input draining.", c->self);
745 if(c->input_filter != NULL) {
746 if (c->input_filter(c, buf, len) == -1) {
747 debug("filter stops channel %d", c->self);
751 buffer_append(&c->input, buf, len);
757 channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
762 /* Send buffered output data to the socket. */
764 FD_ISSET(c->wfd, writeset) &&
765 buffer_len(&c->output) > 0) {
766 len = write(c->wfd, buffer_ptr(&c->output),
767 buffer_len(&c->output));
768 if (len < 0 && (errno == EINTR || errno == EAGAIN))
772 buffer_consume(&c->output, buffer_len(&c->output));
773 debug("Channel %d status set to input draining.", c->self);
774 c->type = SSH_CHANNEL_INPUT_DRAINING;
776 chan_write_failed(c);
780 if (compat20 && c->isatty) {
781 if (tcgetattr(c->wfd, &tio) == 0 &&
782 !(tio.c_lflag & ECHO) && (tio.c_lflag & ICANON)) {
784 * Simulate echo to reduce the impact of
785 * traffic analysis. We need to match the
786 * size of a SSH2_MSG_CHANNEL_DATA message
787 * (4 byte channel id + data)
789 packet_send_ignore(4 + len);
793 buffer_consume(&c->output, len);
794 if (compat20 && len > 0) {
795 c->local_consumed += len;
801 channel_handle_efd(Channel *c, fd_set * readset, fd_set * writeset)
806 /** XXX handle drain efd, too */
808 if (c->extended_usage == CHAN_EXTENDED_WRITE &&
809 FD_ISSET(c->efd, writeset) &&
810 buffer_len(&c->extended) > 0) {
811 len = write(c->efd, buffer_ptr(&c->extended),
812 buffer_len(&c->extended));
813 debug2("channel %d: written %d to efd %d",
814 c->self, len, c->efd);
815 if (len < 0 && (errno == EINTR || errno == EAGAIN))
818 debug2("channel %d: closing write-efd %d",
823 buffer_consume(&c->extended, len);
824 c->local_consumed += len;
826 } else if (c->extended_usage == CHAN_EXTENDED_READ &&
827 FD_ISSET(c->efd, readset)) {
828 len = read(c->efd, buf, sizeof(buf));
829 debug2("channel %d: read %d from efd %d",
830 c->self, len, c->efd);
831 if (len < 0 && (errno == EINTR || errno == EAGAIN))
834 debug2("channel %d: closing read-efd %d",
839 buffer_append(&c->extended, buf, len);
846 channel_check_window(Channel *c)
848 if (!(c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD)) &&
849 c->local_window < c->local_window_max/2 &&
850 c->local_consumed > 0) {
851 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
852 packet_put_int(c->remote_id);
853 packet_put_int(c->local_consumed);
855 debug2("channel %d: window %d sent adjust %d",
856 c->self, c->local_window,
858 c->local_window += c->local_consumed;
859 c->local_consumed = 0;
865 channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
867 channel_handle_rfd(c, readset, writeset);
868 channel_handle_wfd(c, readset, writeset);
872 channel_post_open_2(Channel *c, fd_set * readset, fd_set * writeset)
874 channel_handle_rfd(c, readset, writeset);
875 channel_handle_wfd(c, readset, writeset);
876 channel_handle_efd(c, readset, writeset);
878 channel_check_window(c);
882 channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
885 /* Send buffered output data to the socket. */
886 if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
887 len = write(c->sock, buffer_ptr(&c->output),
888 buffer_len(&c->output));
890 buffer_consume(&c->output, buffer_len(&c->output));
892 buffer_consume(&c->output, len);
897 channel_handler_init_20(void)
899 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_20;
900 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
901 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
902 channel_pre[SSH_CHANNEL_RPORT_LISTENER] = &channel_pre_listener;
903 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
904 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
905 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
907 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_2;
908 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
909 channel_post[SSH_CHANNEL_RPORT_LISTENER] = &channel_post_port_listener;
910 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
911 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
912 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
916 channel_handler_init_13(void)
918 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
919 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
920 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
921 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
922 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
923 channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
924 channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
925 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
927 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
928 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
929 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
930 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
931 channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
932 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
936 channel_handler_init_15(void)
938 channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
939 channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open;
940 channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
941 channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
942 channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
943 channel_pre[SSH_CHANNEL_CONNECTING] = &channel_pre_connecting;
945 channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
946 channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
947 channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
948 channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
949 channel_post[SSH_CHANNEL_CONNECTING] = &channel_post_connecting;
953 channel_handler_init(void)
956 for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
957 channel_pre[i] = NULL;
958 channel_post[i] = NULL;
961 channel_handler_init_20();
963 channel_handler_init_13();
965 channel_handler_init_15();
969 channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
971 static int did_init = 0;
976 channel_handler_init();
979 for (i = 0; i < channels_alloc; i++) {
981 if (c->type == SSH_CHANNEL_FREE)
983 if (ftab[c->type] == NULL)
985 (*ftab[c->type])(c, readset, writeset);
986 if (chan_is_dead(c)) {
988 * we have to remove the fd's from the select mask
989 * before the channels are free'd and the fd's are
993 FD_CLR(c->wfd, writeset);
995 FD_CLR(c->rfd, readset);
997 if (c->extended_usage == CHAN_EXTENDED_READ)
998 FD_CLR(c->efd, readset);
999 if (c->extended_usage == CHAN_EXTENDED_WRITE)
1000 FD_CLR(c->efd, writeset);
1002 channel_free(c->self);
1008 channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp)
1013 n = MAX(*maxfdp, channel_max_fd);
1015 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1016 if (*readsetp == NULL || n > *maxfdp) {
1021 *readsetp = xmalloc(sz);
1022 *writesetp = xmalloc(sz);
1025 memset(*readsetp, 0, sz);
1026 memset(*writesetp, 0, sz);
1028 channel_handler(channel_pre, *readsetp, *writesetp);
1032 channel_after_select(fd_set * readset, fd_set * writeset)
1034 channel_handler(channel_post, readset, writeset);
1037 /* If there is data to send to the connection, enqueue some of it now. */
1040 channel_output_poll()
1045 for (i = 0; i < channels_alloc; i++) {
1048 /* We are only interested in channels that can have buffered incoming data. */
1050 if (c->type != SSH_CHANNEL_OPEN &&
1051 c->type != SSH_CHANNEL_INPUT_DRAINING)
1054 if (c->type != SSH_CHANNEL_OPEN)
1058 (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1059 /* XXX is this true? */
1060 debug2("channel %d: no data after CLOSE", c->self);
1064 /* Get the amount of buffered data for this channel. */
1065 if ((c->istate == CHAN_INPUT_OPEN ||
1066 c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1067 (len = buffer_len(&c->input)) > 0) {
1068 /* Send some data for the other side over the secure connection. */
1070 if (len > c->remote_window)
1071 len = c->remote_window;
1072 if (len > c->remote_maxpacket)
1073 len = c->remote_maxpacket;
1075 if (packet_is_interactive()) {
1079 /* Keep the packets at reasonable size. */
1080 if (len > packet_get_maxsize()/2)
1081 len = packet_get_maxsize()/2;
1085 packet_start(compat20 ?
1086 SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1087 packet_put_int(c->remote_id);
1088 packet_put_string(buffer_ptr(&c->input), len);
1090 buffer_consume(&c->input, len);
1091 c->remote_window -= len;
1093 } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1095 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1097 * input-buffer is empty and read-socket shutdown:
1098 * tell peer, that we will not send more data: send IEOF
1102 /* Send extended data, i.e. stderr */
1104 c->remote_window > 0 &&
1105 (len = buffer_len(&c->extended)) > 0 &&
1106 c->extended_usage == CHAN_EXTENDED_READ) {
1107 debug2("channel %d: rwin %d elen %d euse %d",
1108 c->self, c->remote_window, buffer_len(&c->extended),
1110 if (len > c->remote_window)
1111 len = c->remote_window;
1112 if (len > c->remote_maxpacket)
1113 len = c->remote_maxpacket;
1114 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1115 packet_put_int(c->remote_id);
1116 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1117 packet_put_string(buffer_ptr(&c->extended), len);
1119 buffer_consume(&c->extended, len);
1120 c->remote_window -= len;
1121 debug2("channel %d: sent ext data %d", c->self, len);
1127 * This is called when a packet of type CHANNEL_DATA has just been received.
1128 * The message type has already been consumed, but channel number and data is
1133 channel_input_data(int type, int plen, void *ctxt)
1140 /* Get the channel number and verify it. */
1141 id = packet_get_int();
1142 c = channel_lookup(id);
1144 packet_disconnect("Received data for nonexistent channel %d.", id);
1146 /* Ignore any data for non-open channels (might happen on close) */
1147 if (c->type != SSH_CHANNEL_OPEN &&
1148 c->type != SSH_CHANNEL_X11_OPEN)
1151 /* same for protocol 1.5 if output end is no longer open */
1152 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1156 data = packet_get_string(&data_len);
1160 if (data_len > c->local_maxpacket) {
1161 log("channel %d: rcvd big packet %d, maxpack %d",
1162 c->self, data_len, c->local_maxpacket);
1164 if (data_len > c->local_window) {
1165 log("channel %d: rcvd too much data %d, win %d",
1166 c->self, data_len, c->local_window);
1170 c->local_window -= data_len;
1172 packet_integrity_check(plen, 4 + 4 + data_len, type);
1174 buffer_append(&c->output, data, data_len);
1178 channel_input_extended_data(int type, int plen, void *ctxt)
1186 /* Get the channel number and verify it. */
1187 id = packet_get_int();
1188 c = channel_lookup(id);
1191 packet_disconnect("Received extended_data for bad channel %d.", id);
1192 if (c->type != SSH_CHANNEL_OPEN) {
1193 log("channel %d: ext data for non open", id);
1196 tcode = packet_get_int();
1198 c->extended_usage != CHAN_EXTENDED_WRITE ||
1199 tcode != SSH2_EXTENDED_DATA_STDERR) {
1200 log("channel %d: bad ext data", c->self);
1203 data = packet_get_string(&data_len);
1205 if (data_len > c->local_window) {
1206 log("channel %d: rcvd too much extended_data %d, win %d",
1207 c->self, data_len, c->local_window);
1211 debug2("channel %d: rcvd ext data %d", c->self, data_len);
1212 c->local_window -= data_len;
1213 buffer_append(&c->extended, data, data_len);
1219 * Returns true if no channel has too much buffered data, and false if one or
1220 * more channel is overfull.
1224 channel_not_very_much_buffered_data()
1229 for (i = 0; i < channels_alloc; i++) {
1231 if (c->type == SSH_CHANNEL_OPEN) {
1232 if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
1233 debug("channel %d: big input buffer %d",
1234 c->self, buffer_len(&c->input));
1237 if (buffer_len(&c->output) > packet_get_maxsize()) {
1238 debug("channel %d: big output buffer %d",
1239 c->self, buffer_len(&c->output));
1248 channel_input_ieof(int type, int plen, void *ctxt)
1253 packet_integrity_check(plen, 4, type);
1255 id = packet_get_int();
1256 c = channel_lookup(id);
1258 packet_disconnect("Received ieof for nonexistent channel %d.", id);
1263 channel_input_close(int type, int plen, void *ctxt)
1268 packet_integrity_check(plen, 4, type);
1270 id = packet_get_int();
1271 c = channel_lookup(id);
1273 packet_disconnect("Received close for nonexistent channel %d.", id);
1276 * Send a confirmation that we have closed the channel and no more
1277 * data is coming for it.
1279 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1280 packet_put_int(c->remote_id);
1284 * If the channel is in closed state, we have sent a close request,
1285 * and the other side will eventually respond with a confirmation.
1286 * Thus, we cannot free the channel here, because then there would be
1287 * no-one to receive the confirmation. The channel gets freed when
1288 * the confirmation arrives.
1290 if (c->type != SSH_CHANNEL_CLOSED) {
1292 * Not a closed channel - mark it as draining, which will
1293 * cause it to be freed later.
1295 buffer_consume(&c->input, buffer_len(&c->input));
1296 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1300 /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1302 channel_input_oclose(int type, int plen, void *ctxt)
1304 int id = packet_get_int();
1305 Channel *c = channel_lookup(id);
1306 packet_integrity_check(plen, 4, type);
1308 packet_disconnect("Received oclose for nonexistent channel %d.", id);
1309 chan_rcvd_oclose(c);
1313 channel_input_close_confirmation(int type, int plen, void *ctxt)
1315 int id = packet_get_int();
1316 Channel *c = channel_lookup(id);
1320 packet_disconnect("Received close confirmation for "
1321 "out-of-range channel %d.", id);
1322 if (c->type != SSH_CHANNEL_CLOSED)
1323 packet_disconnect("Received close confirmation for "
1324 "non-closed channel %d (type %d).", id, c->type);
1325 channel_free(c->self);
1329 channel_input_open_confirmation(int type, int plen, void *ctxt)
1335 packet_integrity_check(plen, 4 + 4, type);
1337 id = packet_get_int();
1338 c = channel_lookup(id);
1340 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1341 packet_disconnect("Received open confirmation for "
1342 "non-opening channel %d.", id);
1343 remote_id = packet_get_int();
1344 /* Record the remote channel number and mark that the channel is now open. */
1345 c->remote_id = remote_id;
1346 c->type = SSH_CHANNEL_OPEN;
1349 c->remote_window = packet_get_int();
1350 c->remote_maxpacket = packet_get_int();
1352 if (c->cb_fn != NULL && c->cb_event == type) {
1353 debug2("callback start");
1354 c->cb_fn(c->self, c->cb_arg);
1355 debug2("callback done");
1357 debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1358 c->remote_window, c->remote_maxpacket);
1363 channel_input_open_failure(int type, int plen, void *ctxt)
1366 char *msg = NULL, *lang = NULL;
1370 packet_integrity_check(plen, 4, type);
1372 id = packet_get_int();
1373 c = channel_lookup(id);
1375 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1376 packet_disconnect("Received open failure for "
1377 "non-opening channel %d.", id);
1379 reason = packet_get_int();
1380 if (packet_remaining() > 0) {
1381 msg = packet_get_string(NULL);
1382 lang = packet_get_string(NULL);
1385 log("channel_open_failure: %d: reason %d %s", id,
1386 reason, msg ? msg : "<no additional info>");
1392 /* Free the channel. This will also close the socket. */
1397 channel_input_channel_request(int type, int plen, void *ctxt)
1402 id = packet_get_int();
1403 c = channel_lookup(id);
1406 (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1407 packet_disconnect("Received request for "
1408 "non-open channel %d.", id);
1409 if (c->cb_fn != NULL && c->cb_event == type) {
1410 debug2("callback start");
1411 c->cb_fn(c->self, c->cb_arg);
1412 debug2("callback done");
1414 char *service = packet_get_string(NULL);
1415 debug("channel %d: rcvd request for %s", c->self, service);
1416 debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1422 channel_input_window_adjust(int type, int plen, void *ctxt)
1430 /* Get the channel number and verify it. */
1431 id = packet_get_int();
1432 c = channel_lookup(id);
1434 if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1435 log("Received window adjust for "
1436 "non-open channel %d.", id);
1439 adjust = packet_get_int();
1441 debug2("channel %d: rcvd adjust %d", id, adjust);
1442 c->remote_window += adjust;
1446 * Stops listening for channels, and removes any unix domain sockets that we
1451 channel_stop_listening()
1454 for (i = 0; i < channels_alloc; i++) {
1455 switch (channels[i].type) {
1456 case SSH_CHANNEL_AUTH_SOCKET:
1457 close(channels[i].sock);
1458 unlink(channels[i].path);
1461 case SSH_CHANNEL_PORT_LISTENER:
1462 case SSH_CHANNEL_RPORT_LISTENER:
1463 case SSH_CHANNEL_X11_LISTENER:
1464 close(channels[i].sock);
1474 * Closes the sockets/fds of all channels. This is used to close extra file
1475 * descriptors after a fork.
1482 for (i = 0; i < channels_alloc; i++)
1483 if (channels[i].type != SSH_CHANNEL_FREE)
1484 channel_close_fds(&channels[i]);
1487 /* Returns true if any channel is still open. */
1490 channel_still_open()
1493 for (i = 0; i < channels_alloc; i++)
1494 switch (channels[i].type) {
1495 case SSH_CHANNEL_FREE:
1496 case SSH_CHANNEL_X11_LISTENER:
1497 case SSH_CHANNEL_PORT_LISTENER:
1498 case SSH_CHANNEL_RPORT_LISTENER:
1499 case SSH_CHANNEL_CLOSED:
1500 case SSH_CHANNEL_AUTH_SOCKET:
1501 case SSH_CHANNEL_CONNECTING: /* XXX ??? */
1503 case SSH_CHANNEL_LARVAL:
1505 fatal("cannot happen: SSH_CHANNEL_LARVAL");
1507 case SSH_CHANNEL_OPENING:
1508 case SSH_CHANNEL_OPEN:
1509 case SSH_CHANNEL_X11_OPEN:
1511 case SSH_CHANNEL_INPUT_DRAINING:
1512 case SSH_CHANNEL_OUTPUT_DRAINING:
1514 fatal("cannot happen: OUT_DRAIN");
1517 fatal("channel_still_open: bad channel type %d", channels[i].type);
1524 * Returns a message describing the currently open forwarded connections,
1525 * suitable for sending to the client. The message contains crlf pairs for
1530 channel_open_message()
1536 buffer_init(&buffer);
1537 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
1538 buffer_append(&buffer, buf, strlen(buf));
1539 for (i = 0; i < channels_alloc; i++) {
1540 Channel *c = &channels[i];
1542 case SSH_CHANNEL_FREE:
1543 case SSH_CHANNEL_X11_LISTENER:
1544 case SSH_CHANNEL_PORT_LISTENER:
1545 case SSH_CHANNEL_RPORT_LISTENER:
1546 case SSH_CHANNEL_CLOSED:
1547 case SSH_CHANNEL_AUTH_SOCKET:
1549 case SSH_CHANNEL_LARVAL:
1550 case SSH_CHANNEL_OPENING:
1551 case SSH_CHANNEL_CONNECTING:
1552 case SSH_CHANNEL_OPEN:
1553 case SSH_CHANNEL_X11_OPEN:
1554 case SSH_CHANNEL_INPUT_DRAINING:
1555 case SSH_CHANNEL_OUTPUT_DRAINING:
1556 snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
1557 c->self, c->remote_name,
1558 c->type, c->remote_id,
1559 c->istate, buffer_len(&c->input),
1560 c->ostate, buffer_len(&c->output),
1562 buffer_append(&buffer, buf, strlen(buf));
1565 fatal("channel_open_message: bad channel type %d", c->type);
1569 buffer_append(&buffer, "\0", 1);
1570 cp = xstrdup(buffer_ptr(&buffer));
1571 buffer_free(&buffer);
1576 * Initiate forwarding of connections to local port "port" through the secure
1577 * channel to host:port from remote side.
1580 channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
1581 u_short port_to_connect, int gateway_ports)
1583 return channel_request_forwarding(
1585 host_to_connect, port_to_connect,
1586 gateway_ports, /*remote_fwd*/ 0);
1590 * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
1591 * (SSH_CHANNEL_RPORT_LISTENER).
1594 channel_request_forwarding(
1595 const char *listen_address, u_short listen_port,
1596 const char *host_to_connect, u_short port_to_connect,
1597 int gateway_ports, int remote_fwd)
1599 int success, ch, sock, on = 1, ctype;
1600 struct addrinfo hints, *ai, *aitop;
1601 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1603 struct linger linger;
1608 host = listen_address;
1609 ctype = SSH_CHANNEL_RPORT_LISTENER;
1611 host = host_to_connect;
1612 ctype =SSH_CHANNEL_PORT_LISTENER;
1615 if (strlen(host) > sizeof(channels[0].path) - 1) {
1616 error("Forward host name too long.");
1620 /* XXX listen_address is currently ignored */
1622 * getaddrinfo returns a loopback address if the hostname is
1623 * set to NULL and hints.ai_flags is not AI_PASSIVE
1625 memset(&hints, 0, sizeof(hints));
1626 hints.ai_family = IPv4or6;
1627 hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
1628 hints.ai_socktype = SOCK_STREAM;
1629 snprintf(strport, sizeof strport, "%d", listen_port);
1630 if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
1631 packet_disconnect("getaddrinfo: fatal error");
1633 for (ai = aitop; ai; ai = ai->ai_next) {
1634 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
1636 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1637 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1638 error("channel_request_forwarding: getnameinfo failed");
1641 /* Create a port to listen for the host. */
1642 sock = socket(ai->ai_family, SOCK_STREAM, 0);
1644 /* this is no error since kernel may not support ipv6 */
1645 verbose("socket: %.100s", strerror(errno));
1649 * Set socket options. We would like the socket to disappear
1650 * as soon as it has been closed for whatever reason.
1652 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
1654 linger.l_linger = 5;
1655 setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
1656 debug("Local forwarding listening on %s port %s.", ntop, strport);
1658 /* Bind the socket to the address. */
1659 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1660 /* address can be in use ipv6 address is already bound */
1662 error("bind: %.100s", strerror(errno));
1664 verbose("bind: %.100s", strerror(errno));
1669 /* Start listening for connections on the socket. */
1670 if (listen(sock, 5) < 0) {
1671 error("listen: %.100s", strerror(errno));
1675 /* Allocate a channel number for the socket. */
1676 ch = channel_new("port listener", ctype, sock, sock, -1,
1677 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1678 0, xstrdup("port listener"), 1);
1679 strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
1680 channels[ch].host_port = port_to_connect;
1681 channels[ch].listening_port = listen_port;
1685 error("channel_request_forwarding: cannot listen to port: %d",
1687 freeaddrinfo(aitop);
1692 * Initiate forwarding of connections to port "port" on remote host through
1693 * the secure channel to host:port from local side.
1697 channel_request_remote_forwarding(u_short listen_port,
1698 const char *host_to_connect, u_short port_to_connect)
1700 int payload_len, type, success = 0;
1702 /* Record locally that connection to this host/port is permitted. */
1703 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1704 fatal("channel_request_remote_forwarding: too many forwards");
1706 /* Send the forward request to the remote side. */
1708 const char *address_to_bind = "0.0.0.0";
1709 packet_start(SSH2_MSG_GLOBAL_REQUEST);
1710 packet_put_cstring("tcpip-forward");
1711 packet_put_char(0); /* boolean: want reply */
1712 packet_put_cstring(address_to_bind);
1713 packet_put_int(listen_port);
1715 packet_write_wait();
1716 /* Assume that server accepts the request */
1719 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1720 packet_put_int(listen_port);
1721 packet_put_cstring(host_to_connect);
1722 packet_put_int(port_to_connect);
1724 packet_write_wait();
1726 /* Wait for response from the remote side. */
1727 type = packet_read(&payload_len);
1729 case SSH_SMSG_SUCCESS:
1732 case SSH_SMSG_FAILURE:
1733 log("Warning: Server denied remote port forwarding.");
1736 /* Unknown packet */
1737 packet_disconnect("Protocol error for port forward request:"
1738 "received packet type %d.", type);
1742 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
1743 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
1744 permitted_opens[num_permitted_opens].listen_port = listen_port;
1745 num_permitted_opens++;
1750 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
1751 * listening for the port, and sends back a success reply (or disconnect
1752 * message if there was an error). This never returns if there was an error.
1756 channel_input_port_forward_request(int is_root, int gateway_ports)
1758 u_short port, host_port;
1761 /* Get arguments from the packet. */
1762 port = packet_get_int();
1763 hostname = packet_get_string(NULL);
1764 host_port = packet_get_int();
1768 * Check that an unprivileged user is not trying to forward a
1771 if (port < IPPORT_RESERVED && !is_root)
1772 packet_disconnect("Requested forwarding of port %d but user is not root.",
1775 /* Initiate forwarding */
1776 channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
1778 /* Free the argument string. */
1783 * Permits opening to any host/port if permitted_opens[] is empty. This is
1784 * usually called by the server, because the user could connect to any port
1785 * anyway, and the server has no way to know but to trust the client anyway.
1788 channel_permit_all_opens()
1790 if (num_permitted_opens == 0)
1791 all_opens_permitted = 1;
1795 channel_add_permitted_opens(char *host, int port)
1797 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1798 fatal("channel_request_remote_forwarding: too many forwards");
1799 debug("allow port forwarding to host %s port %d", host, port);
1801 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
1802 permitted_opens[num_permitted_opens].port_to_connect = port;
1803 num_permitted_opens++;
1805 all_opens_permitted = 0;
1809 channel_clear_permitted_opens(void)
1813 for (i = 0; i < num_permitted_opens; i++)
1814 xfree(permitted_opens[i].host_to_connect);
1815 num_permitted_opens = 0;
1820 /* return socket to remote host, port */
1822 connect_to(const char *host, u_short port)
1824 struct addrinfo hints, *ai, *aitop;
1825 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1829 memset(&hints, 0, sizeof(hints));
1830 hints.ai_family = IPv4or6;
1831 hints.ai_socktype = SOCK_STREAM;
1832 snprintf(strport, sizeof strport, "%d", port);
1833 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1834 error("connect_to %.100s: unknown host (%s)", host,
1835 gai_strerror(gaierr));
1838 for (ai = aitop; ai; ai = ai->ai_next) {
1839 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
1841 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1842 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1843 error("connect_to: getnameinfo failed");
1846 sock = socket(ai->ai_family, SOCK_STREAM, 0);
1848 error("socket: %.100s", strerror(errno));
1851 if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1852 fatal("connect_to: F_SETFL: %s", strerror(errno));
1853 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
1854 errno != EINPROGRESS) {
1855 error("connect_to %.100s port %s: %.100s", ntop, strport,
1858 continue; /* fail -- try next */
1860 break; /* success */
1863 freeaddrinfo(aitop);
1865 error("connect_to %.100s port %d: failed.", host, port);
1873 channel_connect_by_listen_adress(u_short listen_port)
1877 for (i = 0; i < num_permitted_opens; i++)
1878 if (permitted_opens[i].listen_port == listen_port)
1880 permitted_opens[i].host_to_connect,
1881 permitted_opens[i].port_to_connect);
1882 error("WARNING: Server requests forwarding for unknown listen_port %d",
1887 /* Check if connecting to that port is permitted and connect. */
1889 channel_connect_to(const char *host, u_short port)
1893 permit = all_opens_permitted;
1895 for (i = 0; i < num_permitted_opens; i++)
1896 if (permitted_opens[i].port_to_connect == port &&
1897 strcmp(permitted_opens[i].host_to_connect, host) == 0)
1902 log("Received request to connect to host %.100s port %d, "
1903 "but the request was denied.", host, port);
1906 return connect_to(host, port);
1910 * This is called after receiving PORT_OPEN message. This attempts to
1911 * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
1912 * or CHANNEL_OPEN_FAILURE.
1916 channel_input_port_open(int type, int plen, void *ctxt)
1919 char *host, *originator_string;
1920 int remote_channel, sock = -1, newch;
1922 remote_channel = packet_get_int();
1923 host = packet_get_string(NULL);
1924 host_port = packet_get_int();
1926 if (have_hostname_in_open) {
1927 originator_string = packet_get_string(NULL);
1929 originator_string = xstrdup("unknown (remote did not supply name)");
1932 sock = channel_connect_to(host, host_port);
1934 newch = channel_allocate(SSH_CHANNEL_CONNECTING,
1935 sock, originator_string);
1936 channels[newch].remote_id = remote_channel;
1938 /*XXX delay answer? */
1939 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1940 packet_put_int(remote_channel);
1941 packet_put_int(newch);
1944 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1945 packet_put_int(remote_channel);
1952 * Creates an internet domain socket for listening for X11 connections.
1953 * Returns a suitable value for the DISPLAY variable, or NULL if an error
1957 #define NUM_SOCKS 10
1960 x11_create_display_inet(int screen_number, int x11_display_offset)
1962 int display_number, sock;
1964 struct addrinfo hints, *ai, *aitop;
1965 char strport[NI_MAXSERV];
1966 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1968 char hostname[MAXHOSTNAMELEN];
1970 for (display_number = x11_display_offset;
1971 display_number < MAX_DISPLAYS;
1973 port = 6000 + display_number;
1974 memset(&hints, 0, sizeof(hints));
1975 hints.ai_family = IPv4or6;
1976 hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */
1977 hints.ai_socktype = SOCK_STREAM;
1978 snprintf(strport, sizeof strport, "%d", port);
1979 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1980 error("getaddrinfo: %.100s", gai_strerror(gaierr));
1983 for (ai = aitop; ai; ai = ai->ai_next) {
1984 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
1986 sock = socket(ai->ai_family, SOCK_STREAM, 0);
1988 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
1989 error("socket: %.100s", strerror(errno));
1992 debug("x11_create_display_inet: Socket family %d not supported",
1997 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1998 debug("bind port %d: %.100s", port, strerror(errno));
1999 shutdown(sock, SHUT_RDWR);
2005 for (n = 0; n < num_socks; n++) {
2006 shutdown(socks[n], SHUT_RDWR);
2012 socks[num_socks++] = sock;
2013 #ifndef DONT_TRY_OTHER_AF
2014 if (num_socks == NUM_SOCKS)
2020 freeaddrinfo(aitop);
2024 if (display_number >= MAX_DISPLAYS) {
2025 error("Failed to allocate internet-domain X11 display socket.");
2028 /* Start listening for connections on the socket. */
2029 for (n = 0; n < num_socks; n++) {
2031 if (listen(sock, 5) < 0) {
2032 error("listen: %.100s", strerror(errno));
2033 shutdown(sock, SHUT_RDWR);
2039 /* Set up a suitable value for the DISPLAY variable. */
2040 if (gethostname(hostname, sizeof(hostname)) < 0)
2041 fatal("gethostname: %.100s", strerror(errno));
2043 #ifdef IPADDR_IN_DISPLAY
2045 * HPUX detects the local hostname in the DISPLAY variable and tries
2046 * to set up a shared memory connection to the server, which it
2047 * incorrectly supposes to be local.
2049 * The workaround - as used in later $$H and other programs - is
2050 * is to set display to the host's IP address.
2054 struct in_addr my_addr;
2056 he = gethostbyname(hostname);
2058 error("[X11-broken-fwd-hostname-workaround] Could not get "
2059 "IP address for hostname %s.", hostname);
2061 packet_send_debug("[X11-broken-fwd-hostname-workaround]"
2062 "Could not get IP address for hostname %s.", hostname);
2064 shutdown(sock, SHUT_RDWR);
2070 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2072 /* Set DISPLAY to <ip address>:screen.display */
2073 snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
2074 display_number, screen_number);
2076 #else /* IPADDR_IN_DISPLAY */
2077 /* Just set DISPLAY to hostname:screen.display */
2078 snprintf(display, sizeof display, "%.400s:%d.%d", hostname,
2079 display_number, screen_number);
2080 #endif /* IPADDR_IN_DISPLAY */
2082 /* Allocate a channel for each socket. */
2083 for (n = 0; n < num_socks; n++) {
2085 (void) channel_new("x11 listener",
2086 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2087 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2088 0, xstrdup("X11 inet listener"), 1);
2091 /* Return a suitable value for the DISPLAY environment variable. */
2092 return xstrdup(display);
2096 #define X_UNIX_PATH "/tmp/.X11-unix/X"
2101 connect_local_xsocket(u_int dnr)
2103 static const char *const x_sockets[] = {
2105 "/var/X/.X11-unix/X" "%u",
2106 "/usr/spool/sockets/X11/" "%u",
2110 struct sockaddr_un addr;
2111 const char *const * path;
2113 for (path = x_sockets; *path; ++path) {
2114 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2116 error("socket: %.100s", strerror(errno));
2117 memset(&addr, 0, sizeof(addr));
2118 addr.sun_family = AF_UNIX;
2119 snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr);
2120 if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2124 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2129 x11_connect_display(void)
2131 int display_number, sock = 0;
2132 const char *display;
2133 char buf[1024], *cp;
2134 struct addrinfo hints, *ai, *aitop;
2135 char strport[NI_MAXSERV];
2138 /* Try to open a socket for the local X server. */
2139 display = getenv("DISPLAY");
2141 error("DISPLAY not set.");
2145 * Now we decode the value of the DISPLAY variable and make a
2146 * connection to the real X server.
2150 * Check if it is a unix domain socket. Unix domain displays are in
2151 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2153 if (strncmp(display, "unix:", 5) == 0 ||
2154 display[0] == ':') {
2155 /* Connect to the unix domain socket. */
2156 if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2157 error("Could not parse display number from DISPLAY: %.100s",
2161 /* Create a socket. */
2162 sock = connect_local_xsocket(display_number);
2166 /* OK, we now have a connection to the display. */
2170 * Connect to an inet socket. The DISPLAY value is supposedly
2171 * hostname:d[.s], where hostname may also be numeric IP address.
2173 strncpy(buf, display, sizeof(buf));
2174 buf[sizeof(buf) - 1] = 0;
2175 cp = strchr(buf, ':');
2177 error("Could not find ':' in DISPLAY: %.100s", display);
2181 /* buf now contains the host name. But first we parse the display number. */
2182 if (sscanf(cp + 1, "%d", &display_number) != 1) {
2183 error("Could not parse display number from DISPLAY: %.100s",
2188 /* Look up the host address */
2189 memset(&hints, 0, sizeof(hints));
2190 hints.ai_family = IPv4or6;
2191 hints.ai_socktype = SOCK_STREAM;
2192 snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2193 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2194 error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
2197 for (ai = aitop; ai; ai = ai->ai_next) {
2198 /* Create a socket. */
2199 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2201 debug("socket: %.100s", strerror(errno));
2204 /* Connect it to the display. */
2205 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2206 debug("connect %.100s port %d: %.100s", buf,
2207 6000 + display_number, strerror(errno));
2214 freeaddrinfo(aitop);
2216 error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
2224 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2225 * the remote channel number. We should do whatever we want, and respond
2226 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2230 x11_input_open(int type, int plen, void *ctxt)
2232 int remote_channel, sock = 0, newch;
2236 /* Get remote channel number. */
2237 remote_channel = packet_get_int();
2239 /* Get remote originator name. */
2240 if (have_hostname_in_open) {
2241 remote_host = packet_get_string(&remote_len);
2244 remote_host = xstrdup("unknown (remote did not supply name)");
2248 debug("Received X11 open request.");
2249 packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN);
2251 /* Obtain a connection to the real X display. */
2252 sock = x11_connect_display();
2254 /* Send refusal to the remote host. */
2255 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2256 packet_put_int(remote_channel);
2259 /* Allocate a channel for this connection. */
2260 newch = channel_allocate(
2261 (x11_saved_proto == NULL) ?
2262 SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN,
2264 channels[newch].remote_id = remote_channel;
2266 /* Send a confirmation to the remote host. */
2267 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2268 packet_put_int(remote_channel);
2269 packet_put_int(newch);
2274 /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2276 deny_input_open(int type, int plen, void *ctxt)
2278 int rchan = packet_get_int();
2280 case SSH_SMSG_AGENT_OPEN:
2281 error("Warning: ssh server tried agent forwarding.");
2283 case SSH_SMSG_X11_OPEN:
2284 error("Warning: ssh server tried X11 forwarding.");
2287 error("deny_input_open: type %d plen %d", type, plen);
2290 error("Warning: this is probably a break in attempt by a malicious server.");
2291 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2292 packet_put_int(rchan);
2297 * Requests forwarding of X11 connections, generates fake authentication
2298 * data, and enables authentication spoofing.
2302 x11_request_forwarding_with_spoofing(int client_session_id,
2303 const char *proto, const char *data)
2305 u_int data_len = (u_int) strlen(data) / 2;
2306 u_int i, value, len;
2312 cp = getenv("DISPLAY");
2314 cp = strchr(cp, ':');
2316 cp = strchr(cp, '.');
2318 screen_number = atoi(cp + 1);
2322 /* Save protocol name. */
2323 x11_saved_proto = xstrdup(proto);
2326 * Extract real authentication data and generate fake data of the
2329 x11_saved_data = xmalloc(data_len);
2330 x11_fake_data = xmalloc(data_len);
2331 for (i = 0; i < data_len; i++) {
2332 if (sscanf(data + 2 * i, "%2x", &value) != 1)
2333 fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2335 rand = arc4random();
2336 x11_saved_data[i] = value;
2337 x11_fake_data[i] = rand & 0xff;
2340 x11_saved_data_len = data_len;
2341 x11_fake_data_len = data_len;
2343 /* Convert the fake data into hex. */
2344 len = 2 * data_len + 1;
2345 new_data = xmalloc(len);
2346 for (i = 0; i < data_len; i++)
2347 snprintf(new_data + 2 * i, len - 2 * i,
2348 "%02x", (u_char) x11_fake_data[i]);
2350 /* Send the request packet. */
2352 channel_request_start(client_session_id, "x11-req", 0);
2353 packet_put_char(0); /* XXX bool single connection */
2355 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2357 packet_put_cstring(proto);
2358 packet_put_cstring(new_data);
2359 packet_put_int(screen_number);
2361 packet_write_wait();
2365 /* Sends a message to the server to request authentication fd forwarding. */
2368 auth_request_forwarding()
2370 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2372 packet_write_wait();
2376 * Returns the name of the forwarded authentication socket. Returns NULL if
2377 * there is no forwarded authentication socket. The returned value points to
2382 auth_get_socket_name()
2384 return channel_forwarded_auth_socket_name;
2387 /* removes the agent forwarding socket */
2390 cleanup_socket(void)
2392 unlink(channel_forwarded_auth_socket_name);
2393 rmdir(channel_forwarded_auth_socket_dir);
2397 * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
2398 * This starts forwarding authentication requests.
2402 auth_input_request_forwarding(struct passwd * pw)
2405 struct sockaddr_un sunaddr;
2407 if (auth_get_socket_name() != NULL)
2408 fatal("Protocol error: authentication forwarding requested twice.");
2410 /* Temporarily drop privileged uid for mkdir/bind. */
2411 temporarily_use_uid(pw->pw_uid);
2413 /* Allocate a buffer for the socket name, and format the name. */
2414 channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME);
2415 channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME);
2416 strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME);
2418 /* Create private directory for socket */
2419 if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) {
2420 packet_send_debug("Agent forwarding disabled: mkdtemp() failed: %.100s",
2423 xfree(channel_forwarded_auth_socket_name);
2424 xfree(channel_forwarded_auth_socket_dir);
2425 channel_forwarded_auth_socket_name = NULL;
2426 channel_forwarded_auth_socket_dir = NULL;
2429 snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d",
2430 channel_forwarded_auth_socket_dir, (int) getpid());
2432 if (atexit(cleanup_socket) < 0) {
2435 packet_disconnect("socket: %.100s", strerror(saved));
2437 /* Create the socket. */
2438 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2440 packet_disconnect("socket: %.100s", strerror(errno));
2442 /* Bind it to the name. */
2443 memset(&sunaddr, 0, sizeof(sunaddr));
2444 sunaddr.sun_family = AF_UNIX;
2445 strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name,
2446 sizeof(sunaddr.sun_path));
2448 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2449 packet_disconnect("bind: %.100s", strerror(errno));
2451 /* Restore the privileged uid. */
2454 /* Start listening on the socket. */
2455 if (listen(sock, 5) < 0)
2456 packet_disconnect("listen: %.100s", strerror(errno));
2458 /* Allocate a channel for the authentication agent socket. */
2459 newch = channel_new("auth socket",
2460 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2461 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2462 0, xstrdup("auth socket"), 1);
2464 strlcpy(channels[newch].path, channel_forwarded_auth_socket_name,
2465 sizeof(channels[newch].path));
2469 /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2472 auth_input_open_request(int type, int plen, void *ctxt)
2474 int remch, sock, newch;
2477 packet_integrity_check(plen, 4, type);
2479 /* Read the remote channel number from the message. */
2480 remch = packet_get_int();
2483 * Get a connection to the local authentication agent (this may again
2486 sock = ssh_get_authentication_socket();
2489 * If we could not connect the agent, send an error message back to
2490 * the server. This should never happen unless the agent dies,
2491 * because authentication forwarding is only enabled if we have an
2495 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2496 packet_put_int(remch);
2500 debug("Forwarding authentication connection.");
2503 * Dummy host name. This will be freed when the channel is freed; it
2504 * will still be valid in the packet_put_string below since the
2505 * channel cannot yet be freed at that point.
2507 dummyname = xstrdup("authentication agent connection");
2509 newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname);
2510 channels[newch].remote_id = remch;
2512 /* Send a confirmation to the remote host. */
2513 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2514 packet_put_int(remch);
2515 packet_put_int(newch);
2520 channel_start_open(int id)
2522 Channel *c = channel_lookup(id);
2524 log("channel_open: %d: bad id", id);
2527 debug("send channel open %d", id);
2528 packet_start(SSH2_MSG_CHANNEL_OPEN);
2529 packet_put_cstring(c->ctype);
2530 packet_put_int(c->self);
2531 packet_put_int(c->local_window);
2532 packet_put_int(c->local_maxpacket);
2535 channel_open(int id)
2538 channel_start_open(id);
2542 channel_request(int id, char *service, int wantconfirm)
2544 channel_request_start(id, service, wantconfirm);
2546 debug("channel request %d: %s", id, service) ;
2549 channel_request_start(int id, char *service, int wantconfirm)
2551 Channel *c = channel_lookup(id);
2553 log("channel_request: %d: bad id", id);
2556 packet_start(SSH2_MSG_CHANNEL_REQUEST);
2557 packet_put_int(c->remote_id);
2558 packet_put_cstring(service);
2559 packet_put_char(wantconfirm);
2562 channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
2564 Channel *c = channel_lookup(id);
2566 log("channel_register_callback: %d: bad id", id);
2569 c->cb_event = mtype;
2574 channel_register_cleanup(int id, channel_callback_fn *fn)
2576 Channel *c = channel_lookup(id);
2578 log("channel_register_cleanup: %d: bad id", id);
2581 c->dettach_user = fn;
2584 channel_cancel_cleanup(int id)
2586 Channel *c = channel_lookup(id);
2588 log("channel_cancel_cleanup: %d: bad id", id);
2591 c->dettach_user = NULL;
2594 channel_register_filter(int id, channel_filter_fn *fn)
2596 Channel *c = channel_lookup(id);
2598 log("channel_register_filter: %d: bad id", id);
2601 c->input_filter = fn;
2605 channel_set_fds(int id, int rfd, int wfd, int efd,
2606 int extusage, int nonblock)
2608 Channel *c = channel_lookup(id);
2609 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
2610 fatal("channel_activate for non-larval channel %d.", id);
2611 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
2612 c->type = SSH_CHANNEL_OPEN;
2613 /* XXX window size? */
2614 c->local_window = c->local_window_max = c->local_maxpacket * 2;
2615 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2616 packet_put_int(c->remote_id);
2617 packet_put_int(c->local_window);