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 1.102 2001/04/06 21:00:10 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,
1014 n = MAX(*maxfdp, channel_max_fd);
1016 sz = howmany(n+1, NFDBITS) * sizeof(fd_mask);
1017 if (*readsetp == NULL || n > *maxfdp) {
1022 *readsetp = xmalloc(sz);
1023 *writesetp = xmalloc(sz);
1026 memset(*readsetp, 0, sz);
1027 memset(*writesetp, 0, sz);
1030 channel_handler(channel_pre, *readsetp, *writesetp);
1034 channel_after_select(fd_set * readset, fd_set * writeset)
1036 channel_handler(channel_post, readset, writeset);
1039 /* If there is data to send to the connection, enqueue some of it now. */
1042 channel_output_poll()
1047 for (i = 0; i < channels_alloc; i++) {
1050 /* We are only interested in channels that can have buffered incoming data. */
1052 if (c->type != SSH_CHANNEL_OPEN &&
1053 c->type != SSH_CHANNEL_INPUT_DRAINING)
1056 if (c->type != SSH_CHANNEL_OPEN)
1060 (c->flags & (CHAN_CLOSE_SENT|CHAN_CLOSE_RCVD))) {
1061 /* XXX is this true? */
1062 debug2("channel %d: no data after CLOSE", c->self);
1066 /* Get the amount of buffered data for this channel. */
1067 if ((c->istate == CHAN_INPUT_OPEN ||
1068 c->istate == CHAN_INPUT_WAIT_DRAIN) &&
1069 (len = buffer_len(&c->input)) > 0) {
1070 /* Send some data for the other side over the secure connection. */
1072 if (len > c->remote_window)
1073 len = c->remote_window;
1074 if (len > c->remote_maxpacket)
1075 len = c->remote_maxpacket;
1077 if (packet_is_interactive()) {
1081 /* Keep the packets at reasonable size. */
1082 if (len > packet_get_maxsize()/2)
1083 len = packet_get_maxsize()/2;
1087 packet_start(compat20 ?
1088 SSH2_MSG_CHANNEL_DATA : SSH_MSG_CHANNEL_DATA);
1089 packet_put_int(c->remote_id);
1090 packet_put_string(buffer_ptr(&c->input), len);
1092 buffer_consume(&c->input, len);
1093 c->remote_window -= len;
1095 } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
1097 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
1099 * input-buffer is empty and read-socket shutdown:
1100 * tell peer, that we will not send more data: send IEOF
1104 /* Send extended data, i.e. stderr */
1106 c->remote_window > 0 &&
1107 (len = buffer_len(&c->extended)) > 0 &&
1108 c->extended_usage == CHAN_EXTENDED_READ) {
1109 debug2("channel %d: rwin %d elen %d euse %d",
1110 c->self, c->remote_window, buffer_len(&c->extended),
1112 if (len > c->remote_window)
1113 len = c->remote_window;
1114 if (len > c->remote_maxpacket)
1115 len = c->remote_maxpacket;
1116 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA);
1117 packet_put_int(c->remote_id);
1118 packet_put_int(SSH2_EXTENDED_DATA_STDERR);
1119 packet_put_string(buffer_ptr(&c->extended), len);
1121 buffer_consume(&c->extended, len);
1122 c->remote_window -= len;
1123 debug2("channel %d: sent ext data %d", c->self, len);
1129 * This is called when a packet of type CHANNEL_DATA has just been received.
1130 * The message type has already been consumed, but channel number and data is
1135 channel_input_data(int type, int plen, void *ctxt)
1142 /* Get the channel number and verify it. */
1143 id = packet_get_int();
1144 c = channel_lookup(id);
1146 packet_disconnect("Received data for nonexistent channel %d.", id);
1148 /* Ignore any data for non-open channels (might happen on close) */
1149 if (c->type != SSH_CHANNEL_OPEN &&
1150 c->type != SSH_CHANNEL_X11_OPEN)
1153 /* same for protocol 1.5 if output end is no longer open */
1154 if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
1158 data = packet_get_string(&data_len);
1162 if (data_len > c->local_maxpacket) {
1163 log("channel %d: rcvd big packet %d, maxpack %d",
1164 c->self, data_len, c->local_maxpacket);
1166 if (data_len > c->local_window) {
1167 log("channel %d: rcvd too much data %d, win %d",
1168 c->self, data_len, c->local_window);
1172 c->local_window -= data_len;
1174 packet_integrity_check(plen, 4 + 4 + data_len, type);
1176 buffer_append(&c->output, data, data_len);
1180 channel_input_extended_data(int type, int plen, void *ctxt)
1188 /* Get the channel number and verify it. */
1189 id = packet_get_int();
1190 c = channel_lookup(id);
1193 packet_disconnect("Received extended_data for bad channel %d.", id);
1194 if (c->type != SSH_CHANNEL_OPEN) {
1195 log("channel %d: ext data for non open", id);
1198 tcode = packet_get_int();
1200 c->extended_usage != CHAN_EXTENDED_WRITE ||
1201 tcode != SSH2_EXTENDED_DATA_STDERR) {
1202 log("channel %d: bad ext data", c->self);
1205 data = packet_get_string(&data_len);
1207 if (data_len > c->local_window) {
1208 log("channel %d: rcvd too much extended_data %d, win %d",
1209 c->self, data_len, c->local_window);
1213 debug2("channel %d: rcvd ext data %d", c->self, data_len);
1214 c->local_window -= data_len;
1215 buffer_append(&c->extended, data, data_len);
1221 * Returns true if no channel has too much buffered data, and false if one or
1222 * more channel is overfull.
1226 channel_not_very_much_buffered_data()
1231 for (i = 0; i < channels_alloc; i++) {
1233 if (c->type == SSH_CHANNEL_OPEN) {
1234 if (!compat20 && buffer_len(&c->input) > packet_get_maxsize()) {
1235 debug("channel %d: big input buffer %d",
1236 c->self, buffer_len(&c->input));
1239 if (buffer_len(&c->output) > packet_get_maxsize()) {
1240 debug("channel %d: big output buffer %d",
1241 c->self, buffer_len(&c->output));
1250 channel_input_ieof(int type, int plen, void *ctxt)
1255 packet_integrity_check(plen, 4, type);
1257 id = packet_get_int();
1258 c = channel_lookup(id);
1260 packet_disconnect("Received ieof for nonexistent channel %d.", id);
1265 channel_input_close(int type, int plen, void *ctxt)
1270 packet_integrity_check(plen, 4, type);
1272 id = packet_get_int();
1273 c = channel_lookup(id);
1275 packet_disconnect("Received close for nonexistent channel %d.", id);
1278 * Send a confirmation that we have closed the channel and no more
1279 * data is coming for it.
1281 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
1282 packet_put_int(c->remote_id);
1286 * If the channel is in closed state, we have sent a close request,
1287 * and the other side will eventually respond with a confirmation.
1288 * Thus, we cannot free the channel here, because then there would be
1289 * no-one to receive the confirmation. The channel gets freed when
1290 * the confirmation arrives.
1292 if (c->type != SSH_CHANNEL_CLOSED) {
1294 * Not a closed channel - mark it as draining, which will
1295 * cause it to be freed later.
1297 buffer_consume(&c->input, buffer_len(&c->input));
1298 c->type = SSH_CHANNEL_OUTPUT_DRAINING;
1302 /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
1304 channel_input_oclose(int type, int plen, void *ctxt)
1306 int id = packet_get_int();
1307 Channel *c = channel_lookup(id);
1308 packet_integrity_check(plen, 4, type);
1310 packet_disconnect("Received oclose for nonexistent channel %d.", id);
1311 chan_rcvd_oclose(c);
1315 channel_input_close_confirmation(int type, int plen, void *ctxt)
1317 int id = packet_get_int();
1318 Channel *c = channel_lookup(id);
1322 packet_disconnect("Received close confirmation for "
1323 "out-of-range channel %d.", id);
1324 if (c->type != SSH_CHANNEL_CLOSED)
1325 packet_disconnect("Received close confirmation for "
1326 "non-closed channel %d (type %d).", id, c->type);
1327 channel_free(c->self);
1331 channel_input_open_confirmation(int type, int plen, void *ctxt)
1337 packet_integrity_check(plen, 4 + 4, type);
1339 id = packet_get_int();
1340 c = channel_lookup(id);
1342 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1343 packet_disconnect("Received open confirmation for "
1344 "non-opening channel %d.", id);
1345 remote_id = packet_get_int();
1346 /* Record the remote channel number and mark that the channel is now open. */
1347 c->remote_id = remote_id;
1348 c->type = SSH_CHANNEL_OPEN;
1351 c->remote_window = packet_get_int();
1352 c->remote_maxpacket = packet_get_int();
1354 if (c->cb_fn != NULL && c->cb_event == type) {
1355 debug2("callback start");
1356 c->cb_fn(c->self, c->cb_arg);
1357 debug2("callback done");
1359 debug("channel %d: open confirm rwindow %d rmax %d", c->self,
1360 c->remote_window, c->remote_maxpacket);
1365 channel_input_open_failure(int type, int plen, void *ctxt)
1368 char *msg = NULL, *lang = NULL;
1372 packet_integrity_check(plen, 4, type);
1374 id = packet_get_int();
1375 c = channel_lookup(id);
1377 if (c==NULL || c->type != SSH_CHANNEL_OPENING)
1378 packet_disconnect("Received open failure for "
1379 "non-opening channel %d.", id);
1381 reason = packet_get_int();
1382 if (packet_remaining() > 0) {
1383 msg = packet_get_string(NULL);
1384 lang = packet_get_string(NULL);
1387 log("channel_open_failure: %d: reason %d %s", id,
1388 reason, msg ? msg : "<no additional info>");
1394 /* Free the channel. This will also close the socket. */
1399 channel_input_channel_request(int type, int plen, void *ctxt)
1404 id = packet_get_int();
1405 c = channel_lookup(id);
1408 (c->type != SSH_CHANNEL_OPEN && c->type != SSH_CHANNEL_LARVAL))
1409 packet_disconnect("Received request for "
1410 "non-open channel %d.", id);
1411 if (c->cb_fn != NULL && c->cb_event == type) {
1412 debug2("callback start");
1413 c->cb_fn(c->self, c->cb_arg);
1414 debug2("callback done");
1416 char *service = packet_get_string(NULL);
1417 debug("channel %d: rcvd request for %s", c->self, service);
1418 debug("cb_fn %p cb_event %d", c->cb_fn , c->cb_event);
1424 channel_input_window_adjust(int type, int plen, void *ctxt)
1432 /* Get the channel number and verify it. */
1433 id = packet_get_int();
1434 c = channel_lookup(id);
1436 if (c == NULL || c->type != SSH_CHANNEL_OPEN) {
1437 log("Received window adjust for "
1438 "non-open channel %d.", id);
1441 adjust = packet_get_int();
1443 debug2("channel %d: rcvd adjust %d", id, adjust);
1444 c->remote_window += adjust;
1448 * Stops listening for channels, and removes any unix domain sockets that we
1453 channel_stop_listening()
1456 for (i = 0; i < channels_alloc; i++) {
1457 switch (channels[i].type) {
1458 case SSH_CHANNEL_AUTH_SOCKET:
1459 close(channels[i].sock);
1460 unlink(channels[i].path);
1463 case SSH_CHANNEL_PORT_LISTENER:
1464 case SSH_CHANNEL_RPORT_LISTENER:
1465 case SSH_CHANNEL_X11_LISTENER:
1466 close(channels[i].sock);
1476 * Closes the sockets/fds of all channels. This is used to close extra file
1477 * descriptors after a fork.
1484 for (i = 0; i < channels_alloc; i++)
1485 if (channels[i].type != SSH_CHANNEL_FREE)
1486 channel_close_fds(&channels[i]);
1489 /* Returns true if any channel is still open. */
1492 channel_still_open()
1495 for (i = 0; i < channels_alloc; i++)
1496 switch (channels[i].type) {
1497 case SSH_CHANNEL_FREE:
1498 case SSH_CHANNEL_X11_LISTENER:
1499 case SSH_CHANNEL_PORT_LISTENER:
1500 case SSH_CHANNEL_RPORT_LISTENER:
1501 case SSH_CHANNEL_CLOSED:
1502 case SSH_CHANNEL_AUTH_SOCKET:
1503 case SSH_CHANNEL_CONNECTING: /* XXX ??? */
1505 case SSH_CHANNEL_LARVAL:
1507 fatal("cannot happen: SSH_CHANNEL_LARVAL");
1509 case SSH_CHANNEL_OPENING:
1510 case SSH_CHANNEL_OPEN:
1511 case SSH_CHANNEL_X11_OPEN:
1513 case SSH_CHANNEL_INPUT_DRAINING:
1514 case SSH_CHANNEL_OUTPUT_DRAINING:
1516 fatal("cannot happen: OUT_DRAIN");
1519 fatal("channel_still_open: bad channel type %d", channels[i].type);
1526 * Returns a message describing the currently open forwarded connections,
1527 * suitable for sending to the client. The message contains crlf pairs for
1532 channel_open_message()
1538 buffer_init(&buffer);
1539 snprintf(buf, sizeof buf, "The following connections are open:\r\n");
1540 buffer_append(&buffer, buf, strlen(buf));
1541 for (i = 0; i < channels_alloc; i++) {
1542 Channel *c = &channels[i];
1544 case SSH_CHANNEL_FREE:
1545 case SSH_CHANNEL_X11_LISTENER:
1546 case SSH_CHANNEL_PORT_LISTENER:
1547 case SSH_CHANNEL_RPORT_LISTENER:
1548 case SSH_CHANNEL_CLOSED:
1549 case SSH_CHANNEL_AUTH_SOCKET:
1551 case SSH_CHANNEL_LARVAL:
1552 case SSH_CHANNEL_OPENING:
1553 case SSH_CHANNEL_CONNECTING:
1554 case SSH_CHANNEL_OPEN:
1555 case SSH_CHANNEL_X11_OPEN:
1556 case SSH_CHANNEL_INPUT_DRAINING:
1557 case SSH_CHANNEL_OUTPUT_DRAINING:
1558 snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
1559 c->self, c->remote_name,
1560 c->type, c->remote_id,
1561 c->istate, buffer_len(&c->input),
1562 c->ostate, buffer_len(&c->output),
1564 buffer_append(&buffer, buf, strlen(buf));
1567 fatal("channel_open_message: bad channel type %d", c->type);
1571 buffer_append(&buffer, "\0", 1);
1572 cp = xstrdup(buffer_ptr(&buffer));
1573 buffer_free(&buffer);
1578 * Initiate forwarding of connections to local port "port" through the secure
1579 * channel to host:port from remote side.
1582 channel_request_local_forwarding(u_short listen_port, const char *host_to_connect,
1583 u_short port_to_connect, int gateway_ports)
1585 return channel_request_forwarding(
1587 host_to_connect, port_to_connect,
1588 gateway_ports, /*remote_fwd*/ 0);
1592 * If 'remote_fwd' is true we have a '-R style' listener for protocol 2
1593 * (SSH_CHANNEL_RPORT_LISTENER).
1596 channel_request_forwarding(
1597 const char *listen_address, u_short listen_port,
1598 const char *host_to_connect, u_short port_to_connect,
1599 int gateway_ports, int remote_fwd)
1601 int success, ch, sock, on = 1, ctype;
1602 struct addrinfo hints, *ai, *aitop;
1603 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1605 struct linger linger;
1610 host = listen_address;
1611 ctype = SSH_CHANNEL_RPORT_LISTENER;
1613 host = host_to_connect;
1614 ctype =SSH_CHANNEL_PORT_LISTENER;
1617 if (strlen(host) > sizeof(channels[0].path) - 1) {
1618 error("Forward host name too long.");
1622 /* XXX listen_address is currently ignored */
1624 * getaddrinfo returns a loopback address if the hostname is
1625 * set to NULL and hints.ai_flags is not AI_PASSIVE
1627 memset(&hints, 0, sizeof(hints));
1628 hints.ai_family = IPv4or6;
1629 hints.ai_flags = gateway_ports ? AI_PASSIVE : 0;
1630 hints.ai_socktype = SOCK_STREAM;
1631 snprintf(strport, sizeof strport, "%d", listen_port);
1632 if (getaddrinfo(NULL, strport, &hints, &aitop) != 0)
1633 packet_disconnect("getaddrinfo: fatal error");
1635 for (ai = aitop; ai; ai = ai->ai_next) {
1636 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
1638 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1639 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1640 error("channel_request_forwarding: getnameinfo failed");
1643 /* Create a port to listen for the host. */
1644 sock = socket(ai->ai_family, SOCK_STREAM, 0);
1646 /* this is no error since kernel may not support ipv6 */
1647 verbose("socket: %.100s", strerror(errno));
1651 * Set socket options. We would like the socket to disappear
1652 * as soon as it has been closed for whatever reason.
1654 setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, (void *)&on, sizeof(on));
1656 linger.l_linger = 5;
1657 setsockopt(sock, SOL_SOCKET, SO_LINGER, (void *)&linger, sizeof(linger));
1658 debug("Local forwarding listening on %s port %s.", ntop, strport);
1660 /* Bind the socket to the address. */
1661 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
1662 /* address can be in use ipv6 address is already bound */
1664 error("bind: %.100s", strerror(errno));
1666 verbose("bind: %.100s", strerror(errno));
1671 /* Start listening for connections on the socket. */
1672 if (listen(sock, 5) < 0) {
1673 error("listen: %.100s", strerror(errno));
1677 /* Allocate a channel number for the socket. */
1678 ch = channel_new("port listener", ctype, sock, sock, -1,
1679 CHAN_TCP_WINDOW_DEFAULT, CHAN_TCP_PACKET_DEFAULT,
1680 0, xstrdup("port listener"), 1);
1681 strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
1682 channels[ch].host_port = port_to_connect;
1683 channels[ch].listening_port = listen_port;
1687 error("channel_request_forwarding: cannot listen to port: %d",
1689 freeaddrinfo(aitop);
1694 * Initiate forwarding of connections to port "port" on remote host through
1695 * the secure channel to host:port from local side.
1699 channel_request_remote_forwarding(u_short listen_port,
1700 const char *host_to_connect, u_short port_to_connect)
1702 int payload_len, type, success = 0;
1704 /* Record locally that connection to this host/port is permitted. */
1705 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1706 fatal("channel_request_remote_forwarding: too many forwards");
1708 /* Send the forward request to the remote side. */
1710 const char *address_to_bind = "0.0.0.0";
1711 packet_start(SSH2_MSG_GLOBAL_REQUEST);
1712 packet_put_cstring("tcpip-forward");
1713 packet_put_char(0); /* boolean: want reply */
1714 packet_put_cstring(address_to_bind);
1715 packet_put_int(listen_port);
1717 packet_write_wait();
1718 /* Assume that server accepts the request */
1721 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
1722 packet_put_int(listen_port);
1723 packet_put_cstring(host_to_connect);
1724 packet_put_int(port_to_connect);
1726 packet_write_wait();
1728 /* Wait for response from the remote side. */
1729 type = packet_read(&payload_len);
1731 case SSH_SMSG_SUCCESS:
1734 case SSH_SMSG_FAILURE:
1735 log("Warning: Server denied remote port forwarding.");
1738 /* Unknown packet */
1739 packet_disconnect("Protocol error for port forward request:"
1740 "received packet type %d.", type);
1744 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
1745 permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
1746 permitted_opens[num_permitted_opens].listen_port = listen_port;
1747 num_permitted_opens++;
1752 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
1753 * listening for the port, and sends back a success reply (or disconnect
1754 * message if there was an error). This never returns if there was an error.
1758 channel_input_port_forward_request(int is_root, int gateway_ports)
1760 u_short port, host_port;
1763 /* Get arguments from the packet. */
1764 port = packet_get_int();
1765 hostname = packet_get_string(NULL);
1766 host_port = packet_get_int();
1770 * Check that an unprivileged user is not trying to forward a
1773 if (port < IPPORT_RESERVED && !is_root)
1774 packet_disconnect("Requested forwarding of port %d but user is not root.",
1777 /* Initiate forwarding */
1778 channel_request_local_forwarding(port, hostname, host_port, gateway_ports);
1780 /* Free the argument string. */
1785 * Permits opening to any host/port if permitted_opens[] is empty. This is
1786 * usually called by the server, because the user could connect to any port
1787 * anyway, and the server has no way to know but to trust the client anyway.
1790 channel_permit_all_opens()
1792 if (num_permitted_opens == 0)
1793 all_opens_permitted = 1;
1797 channel_add_permitted_opens(char *host, int port)
1799 if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
1800 fatal("channel_request_remote_forwarding: too many forwards");
1801 debug("allow port forwarding to host %s port %d", host, port);
1803 permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host);
1804 permitted_opens[num_permitted_opens].port_to_connect = port;
1805 num_permitted_opens++;
1807 all_opens_permitted = 0;
1811 channel_clear_permitted_opens(void)
1815 for (i = 0; i < num_permitted_opens; i++)
1816 xfree(permitted_opens[i].host_to_connect);
1817 num_permitted_opens = 0;
1822 /* return socket to remote host, port */
1824 connect_to(const char *host, u_short port)
1826 struct addrinfo hints, *ai, *aitop;
1827 char ntop[NI_MAXHOST], strport[NI_MAXSERV];
1831 memset(&hints, 0, sizeof(hints));
1832 hints.ai_family = IPv4or6;
1833 hints.ai_socktype = SOCK_STREAM;
1834 snprintf(strport, sizeof strport, "%d", port);
1835 if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
1836 error("connect_to %.100s: unknown host (%s)", host,
1837 gai_strerror(gaierr));
1840 for (ai = aitop; ai; ai = ai->ai_next) {
1841 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
1843 if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
1844 strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
1845 error("connect_to: getnameinfo failed");
1848 sock = socket(ai->ai_family, SOCK_STREAM, 0);
1850 error("socket: %.100s", strerror(errno));
1853 if (fcntl(sock, F_SETFL, O_NONBLOCK) < 0)
1854 fatal("connect_to: F_SETFL: %s", strerror(errno));
1855 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0 &&
1856 errno != EINPROGRESS) {
1857 error("connect_to %.100s port %s: %.100s", ntop, strport,
1860 continue; /* fail -- try next */
1862 break; /* success */
1865 freeaddrinfo(aitop);
1867 error("connect_to %.100s port %d: failed.", host, port);
1875 channel_connect_by_listen_adress(u_short listen_port)
1879 for (i = 0; i < num_permitted_opens; i++)
1880 if (permitted_opens[i].listen_port == listen_port)
1882 permitted_opens[i].host_to_connect,
1883 permitted_opens[i].port_to_connect);
1884 error("WARNING: Server requests forwarding for unknown listen_port %d",
1889 /* Check if connecting to that port is permitted and connect. */
1891 channel_connect_to(const char *host, u_short port)
1895 permit = all_opens_permitted;
1897 for (i = 0; i < num_permitted_opens; i++)
1898 if (permitted_opens[i].port_to_connect == port &&
1899 strcmp(permitted_opens[i].host_to_connect, host) == 0)
1904 log("Received request to connect to host %.100s port %d, "
1905 "but the request was denied.", host, port);
1908 return connect_to(host, port);
1912 * This is called after receiving PORT_OPEN message. This attempts to
1913 * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
1914 * or CHANNEL_OPEN_FAILURE.
1918 channel_input_port_open(int type, int plen, void *ctxt)
1921 char *host, *originator_string;
1922 int remote_channel, sock = -1, newch;
1924 remote_channel = packet_get_int();
1925 host = packet_get_string(NULL);
1926 host_port = packet_get_int();
1928 if (have_hostname_in_open) {
1929 originator_string = packet_get_string(NULL);
1931 originator_string = xstrdup("unknown (remote did not supply name)");
1934 sock = channel_connect_to(host, host_port);
1936 newch = channel_allocate(SSH_CHANNEL_CONNECTING,
1937 sock, originator_string);
1938 channels[newch].remote_id = remote_channel;
1940 /*XXX delay answer? */
1941 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
1942 packet_put_int(remote_channel);
1943 packet_put_int(newch);
1946 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
1947 packet_put_int(remote_channel);
1954 * Creates an internet domain socket for listening for X11 connections.
1955 * Returns a suitable value for the DISPLAY variable, or NULL if an error
1959 #define NUM_SOCKS 10
1962 x11_create_display_inet(int screen_number, int x11_display_offset)
1964 int display_number, sock;
1966 struct addrinfo hints, *ai, *aitop;
1967 char strport[NI_MAXSERV];
1968 int gaierr, n, num_socks = 0, socks[NUM_SOCKS];
1970 char hostname[MAXHOSTNAMELEN];
1972 for (display_number = x11_display_offset;
1973 display_number < MAX_DISPLAYS;
1975 port = 6000 + display_number;
1976 memset(&hints, 0, sizeof(hints));
1977 hints.ai_family = IPv4or6;
1978 hints.ai_flags = AI_PASSIVE; /* XXX loopback only ? */
1979 hints.ai_socktype = SOCK_STREAM;
1980 snprintf(strport, sizeof strport, "%d", port);
1981 if ((gaierr = getaddrinfo(NULL, strport, &hints, &aitop)) != 0) {
1982 error("getaddrinfo: %.100s", gai_strerror(gaierr));
1985 for (ai = aitop; ai; ai = ai->ai_next) {
1986 if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
1988 sock = socket(ai->ai_family, SOCK_STREAM, 0);
1990 if ((errno != EINVAL) && (errno != EAFNOSUPPORT)) {
1991 error("socket: %.100s", strerror(errno));
1994 debug("x11_create_display_inet: Socket family %d not supported",
1999 if (bind(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2000 debug("bind port %d: %.100s", port, strerror(errno));
2001 shutdown(sock, SHUT_RDWR);
2007 for (n = 0; n < num_socks; n++) {
2008 shutdown(socks[n], SHUT_RDWR);
2014 socks[num_socks++] = sock;
2015 #ifndef DONT_TRY_OTHER_AF
2016 if (num_socks == NUM_SOCKS)
2022 freeaddrinfo(aitop);
2026 if (display_number >= MAX_DISPLAYS) {
2027 error("Failed to allocate internet-domain X11 display socket.");
2030 /* Start listening for connections on the socket. */
2031 for (n = 0; n < num_socks; n++) {
2033 if (listen(sock, 5) < 0) {
2034 error("listen: %.100s", strerror(errno));
2035 shutdown(sock, SHUT_RDWR);
2041 /* Set up a suitable value for the DISPLAY variable. */
2042 if (gethostname(hostname, sizeof(hostname)) < 0)
2043 fatal("gethostname: %.100s", strerror(errno));
2045 #ifdef IPADDR_IN_DISPLAY
2047 * HPUX detects the local hostname in the DISPLAY variable and tries
2048 * to set up a shared memory connection to the server, which it
2049 * incorrectly supposes to be local.
2051 * The workaround - as used in later $$H and other programs - is
2052 * is to set display to the host's IP address.
2056 struct in_addr my_addr;
2058 he = gethostbyname(hostname);
2060 error("[X11-broken-fwd-hostname-workaround] Could not get "
2061 "IP address for hostname %s.", hostname);
2063 packet_send_debug("[X11-broken-fwd-hostname-workaround]"
2064 "Could not get IP address for hostname %s.", hostname);
2066 shutdown(sock, SHUT_RDWR);
2072 memcpy(&my_addr, he->h_addr_list[0], sizeof(struct in_addr));
2074 /* Set DISPLAY to <ip address>:screen.display */
2075 snprintf(display, sizeof(display), "%.50s:%d.%d", inet_ntoa(my_addr),
2076 display_number, screen_number);
2078 #else /* IPADDR_IN_DISPLAY */
2079 /* Just set DISPLAY to hostname:screen.display */
2080 snprintf(display, sizeof display, "%.400s:%d.%d", hostname,
2081 display_number, screen_number);
2082 #endif /* IPADDR_IN_DISPLAY */
2084 /* Allocate a channel for each socket. */
2085 for (n = 0; n < num_socks; n++) {
2087 (void) channel_new("x11 listener",
2088 SSH_CHANNEL_X11_LISTENER, sock, sock, -1,
2089 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2090 0, xstrdup("X11 inet listener"), 1);
2093 /* Return a suitable value for the DISPLAY environment variable. */
2094 return xstrdup(display);
2098 #define X_UNIX_PATH "/tmp/.X11-unix/X"
2103 connect_local_xsocket(u_int dnr)
2105 static const char *const x_sockets[] = {
2107 "/var/X/.X11-unix/X" "%u",
2108 "/usr/spool/sockets/X11/" "%u",
2112 struct sockaddr_un addr;
2113 const char *const * path;
2115 for (path = x_sockets; *path; ++path) {
2116 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2118 error("socket: %.100s", strerror(errno));
2119 memset(&addr, 0, sizeof(addr));
2120 addr.sun_family = AF_UNIX;
2121 snprintf(addr.sun_path, sizeof addr.sun_path, *path, dnr);
2122 if (connect(sock, (struct sockaddr *) & addr, sizeof(addr)) == 0)
2126 error("connect %.100s: %.100s", addr.sun_path, strerror(errno));
2131 x11_connect_display(void)
2133 int display_number, sock = 0;
2134 const char *display;
2135 char buf[1024], *cp;
2136 struct addrinfo hints, *ai, *aitop;
2137 char strport[NI_MAXSERV];
2140 /* Try to open a socket for the local X server. */
2141 display = getenv("DISPLAY");
2143 error("DISPLAY not set.");
2147 * Now we decode the value of the DISPLAY variable and make a
2148 * connection to the real X server.
2152 * Check if it is a unix domain socket. Unix domain displays are in
2153 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
2155 if (strncmp(display, "unix:", 5) == 0 ||
2156 display[0] == ':') {
2157 /* Connect to the unix domain socket. */
2158 if (sscanf(strrchr(display, ':') + 1, "%d", &display_number) != 1) {
2159 error("Could not parse display number from DISPLAY: %.100s",
2163 /* Create a socket. */
2164 sock = connect_local_xsocket(display_number);
2168 /* OK, we now have a connection to the display. */
2172 * Connect to an inet socket. The DISPLAY value is supposedly
2173 * hostname:d[.s], where hostname may also be numeric IP address.
2175 strncpy(buf, display, sizeof(buf));
2176 buf[sizeof(buf) - 1] = 0;
2177 cp = strchr(buf, ':');
2179 error("Could not find ':' in DISPLAY: %.100s", display);
2183 /* buf now contains the host name. But first we parse the display number. */
2184 if (sscanf(cp + 1, "%d", &display_number) != 1) {
2185 error("Could not parse display number from DISPLAY: %.100s",
2190 /* Look up the host address */
2191 memset(&hints, 0, sizeof(hints));
2192 hints.ai_family = IPv4or6;
2193 hints.ai_socktype = SOCK_STREAM;
2194 snprintf(strport, sizeof strport, "%d", 6000 + display_number);
2195 if ((gaierr = getaddrinfo(buf, strport, &hints, &aitop)) != 0) {
2196 error("%.100s: unknown host. (%s)", buf, gai_strerror(gaierr));
2199 for (ai = aitop; ai; ai = ai->ai_next) {
2200 /* Create a socket. */
2201 sock = socket(ai->ai_family, SOCK_STREAM, 0);
2203 debug("socket: %.100s", strerror(errno));
2206 /* Connect it to the display. */
2207 if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
2208 debug("connect %.100s port %d: %.100s", buf,
2209 6000 + display_number, strerror(errno));
2216 freeaddrinfo(aitop);
2218 error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
2226 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
2227 * the remote channel number. We should do whatever we want, and respond
2228 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
2232 x11_input_open(int type, int plen, void *ctxt)
2234 int remote_channel, sock = 0, newch;
2238 /* Get remote channel number. */
2239 remote_channel = packet_get_int();
2241 /* Get remote originator name. */
2242 if (have_hostname_in_open) {
2243 remote_host = packet_get_string(&remote_len);
2246 remote_host = xstrdup("unknown (remote did not supply name)");
2250 debug("Received X11 open request.");
2251 packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN);
2253 /* Obtain a connection to the real X display. */
2254 sock = x11_connect_display();
2256 /* Send refusal to the remote host. */
2257 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2258 packet_put_int(remote_channel);
2261 /* Allocate a channel for this connection. */
2262 newch = channel_allocate(
2263 (x11_saved_proto == NULL) ?
2264 SSH_CHANNEL_OPEN : SSH_CHANNEL_X11_OPEN,
2266 channels[newch].remote_id = remote_channel;
2268 /* Send a confirmation to the remote host. */
2269 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2270 packet_put_int(remote_channel);
2271 packet_put_int(newch);
2276 /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
2278 deny_input_open(int type, int plen, void *ctxt)
2280 int rchan = packet_get_int();
2282 case SSH_SMSG_AGENT_OPEN:
2283 error("Warning: ssh server tried agent forwarding.");
2285 case SSH_SMSG_X11_OPEN:
2286 error("Warning: ssh server tried X11 forwarding.");
2289 error("deny_input_open: type %d plen %d", type, plen);
2292 error("Warning: this is probably a break in attempt by a malicious server.");
2293 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2294 packet_put_int(rchan);
2299 * Requests forwarding of X11 connections, generates fake authentication
2300 * data, and enables authentication spoofing.
2304 x11_request_forwarding_with_spoofing(int client_session_id,
2305 const char *proto, const char *data)
2307 u_int data_len = (u_int) strlen(data) / 2;
2308 u_int i, value, len;
2314 cp = getenv("DISPLAY");
2316 cp = strchr(cp, ':');
2318 cp = strchr(cp, '.');
2320 screen_number = atoi(cp + 1);
2324 /* Save protocol name. */
2325 x11_saved_proto = xstrdup(proto);
2328 * Extract real authentication data and generate fake data of the
2331 x11_saved_data = xmalloc(data_len);
2332 x11_fake_data = xmalloc(data_len);
2333 for (i = 0; i < data_len; i++) {
2334 if (sscanf(data + 2 * i, "%2x", &value) != 1)
2335 fatal("x11_request_forwarding: bad authentication data: %.100s", data);
2337 rand = arc4random();
2338 x11_saved_data[i] = value;
2339 x11_fake_data[i] = rand & 0xff;
2342 x11_saved_data_len = data_len;
2343 x11_fake_data_len = data_len;
2345 /* Convert the fake data into hex. */
2346 len = 2 * data_len + 1;
2347 new_data = xmalloc(len);
2348 for (i = 0; i < data_len; i++)
2349 snprintf(new_data + 2 * i, len - 2 * i,
2350 "%02x", (u_char) x11_fake_data[i]);
2352 /* Send the request packet. */
2354 channel_request_start(client_session_id, "x11-req", 0);
2355 packet_put_char(0); /* XXX bool single connection */
2357 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING);
2359 packet_put_cstring(proto);
2360 packet_put_cstring(new_data);
2361 packet_put_int(screen_number);
2363 packet_write_wait();
2367 /* Sends a message to the server to request authentication fd forwarding. */
2370 auth_request_forwarding()
2372 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING);
2374 packet_write_wait();
2378 * Returns the name of the forwarded authentication socket. Returns NULL if
2379 * there is no forwarded authentication socket. The returned value points to
2384 auth_get_socket_name()
2386 return channel_forwarded_auth_socket_name;
2389 /* removes the agent forwarding socket */
2392 cleanup_socket(void)
2394 unlink(channel_forwarded_auth_socket_name);
2395 rmdir(channel_forwarded_auth_socket_dir);
2399 * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
2400 * This starts forwarding authentication requests.
2404 auth_input_request_forwarding(struct passwd * pw)
2407 struct sockaddr_un sunaddr;
2409 if (auth_get_socket_name() != NULL)
2410 fatal("Protocol error: authentication forwarding requested twice.");
2412 /* Temporarily drop privileged uid for mkdir/bind. */
2413 temporarily_use_uid(pw);
2415 /* Allocate a buffer for the socket name, and format the name. */
2416 channel_forwarded_auth_socket_name = xmalloc(MAX_SOCKET_NAME);
2417 channel_forwarded_auth_socket_dir = xmalloc(MAX_SOCKET_NAME);
2418 strlcpy(channel_forwarded_auth_socket_dir, "/tmp/ssh-XXXXXXXX", MAX_SOCKET_NAME);
2420 /* Create private directory for socket */
2421 if (mkdtemp(channel_forwarded_auth_socket_dir) == NULL) {
2422 packet_send_debug("Agent forwarding disabled: mkdtemp() failed: %.100s",
2425 xfree(channel_forwarded_auth_socket_name);
2426 xfree(channel_forwarded_auth_socket_dir);
2427 channel_forwarded_auth_socket_name = NULL;
2428 channel_forwarded_auth_socket_dir = NULL;
2431 snprintf(channel_forwarded_auth_socket_name, MAX_SOCKET_NAME, "%s/agent.%d",
2432 channel_forwarded_auth_socket_dir, (int) getpid());
2434 if (atexit(cleanup_socket) < 0) {
2437 packet_disconnect("socket: %.100s", strerror(saved));
2439 /* Create the socket. */
2440 sock = socket(AF_UNIX, SOCK_STREAM, 0);
2442 packet_disconnect("socket: %.100s", strerror(errno));
2444 /* Bind it to the name. */
2445 memset(&sunaddr, 0, sizeof(sunaddr));
2446 sunaddr.sun_family = AF_UNIX;
2447 strncpy(sunaddr.sun_path, channel_forwarded_auth_socket_name,
2448 sizeof(sunaddr.sun_path));
2450 if (bind(sock, (struct sockaddr *) & sunaddr, sizeof(sunaddr)) < 0)
2451 packet_disconnect("bind: %.100s", strerror(errno));
2453 /* Restore the privileged uid. */
2456 /* Start listening on the socket. */
2457 if (listen(sock, 5) < 0)
2458 packet_disconnect("listen: %.100s", strerror(errno));
2460 /* Allocate a channel for the authentication agent socket. */
2461 newch = channel_new("auth socket",
2462 SSH_CHANNEL_AUTH_SOCKET, sock, sock, -1,
2463 CHAN_X11_WINDOW_DEFAULT, CHAN_X11_PACKET_DEFAULT,
2464 0, xstrdup("auth socket"), 1);
2466 strlcpy(channels[newch].path, channel_forwarded_auth_socket_name,
2467 sizeof(channels[newch].path));
2471 /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
2474 auth_input_open_request(int type, int plen, void *ctxt)
2476 int remch, sock, newch;
2479 packet_integrity_check(plen, 4, type);
2481 /* Read the remote channel number from the message. */
2482 remch = packet_get_int();
2485 * Get a connection to the local authentication agent (this may again
2488 sock = ssh_get_authentication_socket();
2491 * If we could not connect the agent, send an error message back to
2492 * the server. This should never happen unless the agent dies,
2493 * because authentication forwarding is only enabled if we have an
2497 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
2498 packet_put_int(remch);
2502 debug("Forwarding authentication connection.");
2505 * Dummy host name. This will be freed when the channel is freed; it
2506 * will still be valid in the packet_put_string below since the
2507 * channel cannot yet be freed at that point.
2509 dummyname = xstrdup("authentication agent connection");
2511 newch = channel_allocate(SSH_CHANNEL_OPEN, sock, dummyname);
2512 channels[newch].remote_id = remch;
2514 /* Send a confirmation to the remote host. */
2515 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
2516 packet_put_int(remch);
2517 packet_put_int(newch);
2522 channel_start_open(int id)
2524 Channel *c = channel_lookup(id);
2526 log("channel_open: %d: bad id", id);
2529 debug("send channel open %d", id);
2530 packet_start(SSH2_MSG_CHANNEL_OPEN);
2531 packet_put_cstring(c->ctype);
2532 packet_put_int(c->self);
2533 packet_put_int(c->local_window);
2534 packet_put_int(c->local_maxpacket);
2537 channel_open(int id)
2540 channel_start_open(id);
2544 channel_request(int id, char *service, int wantconfirm)
2546 channel_request_start(id, service, wantconfirm);
2548 debug("channel request %d: %s", id, service) ;
2551 channel_request_start(int id, char *service, int wantconfirm)
2553 Channel *c = channel_lookup(id);
2555 log("channel_request: %d: bad id", id);
2558 packet_start(SSH2_MSG_CHANNEL_REQUEST);
2559 packet_put_int(c->remote_id);
2560 packet_put_cstring(service);
2561 packet_put_char(wantconfirm);
2564 channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg)
2566 Channel *c = channel_lookup(id);
2568 log("channel_register_callback: %d: bad id", id);
2571 c->cb_event = mtype;
2576 channel_register_cleanup(int id, channel_callback_fn *fn)
2578 Channel *c = channel_lookup(id);
2580 log("channel_register_cleanup: %d: bad id", id);
2583 c->dettach_user = fn;
2586 channel_cancel_cleanup(int id)
2588 Channel *c = channel_lookup(id);
2590 log("channel_cancel_cleanup: %d: bad id", id);
2593 c->dettach_user = NULL;
2596 channel_register_filter(int id, channel_filter_fn *fn)
2598 Channel *c = channel_lookup(id);
2600 log("channel_register_filter: %d: bad id", id);
2603 c->input_filter = fn;
2607 channel_set_fds(int id, int rfd, int wfd, int efd,
2608 int extusage, int nonblock)
2610 Channel *c = channel_lookup(id);
2611 if (c == NULL || c->type != SSH_CHANNEL_LARVAL)
2612 fatal("channel_activate for non-larval channel %d.", id);
2613 channel_register_fds(c, rfd, wfd, efd, extusage, nonblock);
2614 c->type = SSH_CHANNEL_OPEN;
2615 /* XXX window size? */
2616 c->local_window = c->local_window_max = c->local_maxpacket * 2;
2617 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST);
2618 packet_put_int(c->remote_id);
2619 packet_put_int(c->local_window);