1 /* $OpenBSD: channels.c,v 1.351 2016/07/19 11:38:53 dtucker Exp $ */
3 * Author: Tatu Ylonen <ylo@cs.hut.fi>
4 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * This file contains functions for generic socket connection forwarding.
7 * There is also code for initiating connection forwarding for X11 connections,
8 * arbitrary tcp/ip connections, and the authentication agent connection.
10 * As far as I am concerned, the code I have written for this software
11 * can be used freely for any purpose. Any derived versions of this
12 * software must be clearly marked as such, and if the derived work is
13 * incompatible with the protocol description in the RFC file, it must be
14 * called by a name other than "ssh" or "Secure Shell".
16 * SSH2 support added by Markus Friedl.
17 * Copyright (c) 1999, 2000, 2001, 2002 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.
44 #include <sys/types.h>
45 #include <sys/param.h> /* MIN MAX */
47 #include <sys/ioctl.h>
49 #include <sys/socket.h>
50 #ifdef HAVE_SYS_TIME_H
51 # include <sys/time.h>
54 #include <netinet/in.h>
55 #include <arpa/inet.h>
70 #include "openbsd-compat/sys-queue.h"
84 #include "pathnames.h"
89 * Pointer to an array containing all allocated channels. The array is
90 * dynamically extended as needed.
92 static Channel
**channels
= NULL
;
95 * Size of the channel array. All slots of the array must always be
96 * initialized (at least the type field); unused slots set to NULL
98 static u_int channels_alloc
= 0;
101 * Maximum file descriptor value used in any of the channels. This is
102 * updated in channel_new.
104 static int channel_max_fd
= 0;
107 /* -- tcp forwarding */
110 * Data structure for storing which hosts are permitted for forward requests.
111 * The local sides of any remote forwards are stored in this array to prevent
112 * a corrupt remote server from accessing arbitrary TCP/IP ports on our local
113 * network (which might be behind a firewall).
115 /* XXX: streamlocal wants a path instead of host:port */
116 /* Overload host_to_connect; we could just make this match Forward */
117 /* XXX - can we use listen_host instead of listen_path? */
119 char *host_to_connect
; /* Connect to 'host'. */
120 int port_to_connect
; /* Connect to 'port'. */
121 char *listen_host
; /* Remote side should listen address. */
122 char *listen_path
; /* Remote side should listen path. */
123 int listen_port
; /* Remote side should listen port. */
126 /* List of all permitted host/port pairs to connect by the user. */
127 static ForwardPermission
*permitted_opens
= NULL
;
129 /* List of all permitted host/port pairs to connect by the admin. */
130 static ForwardPermission
*permitted_adm_opens
= NULL
;
132 /* Number of permitted host/port pairs in the array permitted by the user. */
133 static int num_permitted_opens
= 0;
135 /* Number of permitted host/port pair in the array permitted by the admin. */
136 static int num_adm_permitted_opens
= 0;
138 /* special-case port number meaning allow any port */
139 #define FWD_PERMIT_ANY_PORT 0
141 /* special-case wildcard meaning allow any host */
142 #define FWD_PERMIT_ANY_HOST "*"
145 * If this is true, all opens are permitted. This is the case on the server
146 * on which we have to trust the client anyway, and the user could do
147 * anything after logging in anyway.
149 static int all_opens_permitted
= 0;
152 /* -- X11 forwarding */
154 /* Maximum number of fake X11 displays to try. */
155 #define MAX_DISPLAYS 1000
157 /* Saved X11 local (client) display. */
158 static char *x11_saved_display
= NULL
;
160 /* Saved X11 authentication protocol name. */
161 static char *x11_saved_proto
= NULL
;
163 /* Saved X11 authentication data. This is the real data. */
164 static char *x11_saved_data
= NULL
;
165 static u_int x11_saved_data_len
= 0;
167 /* Deadline after which all X11 connections are refused */
168 static u_int x11_refuse_time
;
171 * Fake X11 authentication data. This is what the server will be sending us;
172 * we should replace any occurrences of this by the real data.
174 static u_char
*x11_fake_data
= NULL
;
175 static u_int x11_fake_data_len
;
178 /* -- agent forwarding */
182 /* AF_UNSPEC or AF_INET or AF_INET6 */
183 static int IPv4or6
= AF_UNSPEC
;
186 static void port_open_helper(Channel
*c
, char *rtype
);
188 /* non-blocking connect helpers */
189 static int connect_next(struct channel_connect
*);
190 static void channel_connect_ctx_free(struct channel_connect
*);
192 /* -- channel core */
195 channel_by_id(int id
)
199 if (id
< 0 || (u_int
)id
>= channels_alloc
) {
200 logit("channel_by_id: %d: bad id", id
);
205 logit("channel_by_id: %d: bad id: channel free", id
);
212 * Returns the channel if it is allowed to receive protocol messages.
213 * Private channels, like listening sockets, may not receive messages.
216 channel_lookup(int id
)
220 if ((c
= channel_by_id(id
)) == NULL
)
224 case SSH_CHANNEL_X11_OPEN
:
225 case SSH_CHANNEL_LARVAL
:
226 case SSH_CHANNEL_CONNECTING
:
227 case SSH_CHANNEL_DYNAMIC
:
228 case SSH_CHANNEL_OPENING
:
229 case SSH_CHANNEL_OPEN
:
230 case SSH_CHANNEL_INPUT_DRAINING
:
231 case SSH_CHANNEL_OUTPUT_DRAINING
:
232 case SSH_CHANNEL_ABANDONED
:
235 logit("Non-public channel %d, type %d.", id
, c
->type
);
240 * Register filedescriptors for a channel, used when allocating a channel or
241 * when the channel consumer/producer is ready, e.g. shell exec'd
244 channel_register_fds(Channel
*c
, int rfd
, int wfd
, int efd
,
245 int extusage
, int nonblock
, int is_tty
)
247 /* Update the maximum file descriptor value. */
248 channel_max_fd
= MAX(channel_max_fd
, rfd
);
249 channel_max_fd
= MAX(channel_max_fd
, wfd
);
250 channel_max_fd
= MAX(channel_max_fd
, efd
);
253 fcntl(rfd
, F_SETFD
, FD_CLOEXEC
);
254 if (wfd
!= -1 && wfd
!= rfd
)
255 fcntl(wfd
, F_SETFD
, FD_CLOEXEC
);
256 if (efd
!= -1 && efd
!= rfd
&& efd
!= wfd
)
257 fcntl(efd
, F_SETFD
, FD_CLOEXEC
);
261 c
->sock
= (rfd
== wfd
) ? rfd
: -1;
263 c
->extended_usage
= extusage
;
265 if ((c
->isatty
= is_tty
) != 0)
266 debug2("channel %d: rfd %d isatty", c
->self
, c
->rfd
);
268 /* XXX: Later AIX versions can't push as much data to tty */
269 c
->wfd_isatty
= is_tty
|| isatty(c
->wfd
);
272 /* enable nonblocking mode */
284 * Allocate a new channel object and set its type and socket. This will cause
285 * remote_name to be freed.
288 channel_new(char *ctype
, int type
, int rfd
, int wfd
, int efd
,
289 u_int window
, u_int maxpack
, int extusage
, char *remote_name
, int nonblock
)
295 /* Do initial allocation if this is the first call. */
296 if (channels_alloc
== 0) {
298 channels
= xcalloc(channels_alloc
, sizeof(Channel
*));
299 for (i
= 0; i
< channels_alloc
; i
++)
302 /* Try to find a free slot where to put the new channel. */
303 for (found
= -1, i
= 0; i
< channels_alloc
; i
++)
304 if (channels
[i
] == NULL
) {
305 /* Found a free slot. */
310 /* There are no free slots. Take last+1 slot and expand the array. */
311 found
= channels_alloc
;
312 if (channels_alloc
> 10000)
313 fatal("channel_new: internal error: channels_alloc %d "
314 "too big.", channels_alloc
);
315 channels
= xreallocarray(channels
, channels_alloc
+ 10,
317 channels_alloc
+= 10;
318 debug2("channel: expanding %d", channels_alloc
);
319 for (i
= found
; i
< channels_alloc
; i
++)
322 /* Initialize and return new channel. */
323 c
= channels
[found
] = xcalloc(1, sizeof(Channel
));
324 buffer_init(&c
->input
);
325 buffer_init(&c
->output
);
326 buffer_init(&c
->extended
);
328 c
->listening_addr
= NULL
;
329 c
->listening_port
= 0;
330 c
->ostate
= CHAN_OUTPUT_OPEN
;
331 c
->istate
= CHAN_INPUT_OPEN
;
333 channel_register_fds(c
, rfd
, wfd
, efd
, extusage
, nonblock
, 0);
338 c
->local_window
= window
;
339 c
->local_window_max
= window
;
340 c
->local_consumed
= 0;
341 c
->local_maxpacket
= maxpack
;
343 c
->remote_name
= xstrdup(remote_name
);
344 c
->remote_window
= 0;
345 c
->remote_maxpacket
= 0;
347 c
->single_connection
= 0;
348 c
->detach_user
= NULL
;
350 c
->open_confirm
= NULL
;
351 c
->open_confirm_ctx
= NULL
;
352 c
->input_filter
= NULL
;
353 c
->output_filter
= NULL
;
354 c
->filter_ctx
= NULL
;
355 c
->filter_cleanup
= NULL
;
360 c
->delayed
= 1; /* prevent call to channel_post handler */
361 TAILQ_INIT(&c
->status_confirms
);
362 debug("channel %d: new [%s]", found
, remote_name
);
367 channel_find_maxfd(void)
373 for (i
= 0; i
< channels_alloc
; i
++) {
376 max
= MAX(max
, c
->rfd
);
377 max
= MAX(max
, c
->wfd
);
378 max
= MAX(max
, c
->efd
);
385 channel_close_fd(int *fdp
)
387 int ret
= 0, fd
= *fdp
;
392 if (fd
== channel_max_fd
)
393 channel_max_fd
= channel_find_maxfd();
398 /* Close all channel fd/socket. */
400 channel_close_fds(Channel
*c
)
402 channel_close_fd(&c
->sock
);
403 channel_close_fd(&c
->rfd
);
404 channel_close_fd(&c
->wfd
);
405 channel_close_fd(&c
->efd
);
408 /* Free the channel and close its fd/socket. */
410 channel_free(Channel
*c
)
414 struct channel_confirm
*cc
;
416 for (n
= 0, i
= 0; i
< channels_alloc
; i
++)
419 debug("channel %d: free: %s, nchannels %u", c
->self
,
420 c
->remote_name
? c
->remote_name
: "???", n
);
422 s
= channel_open_message();
423 debug3("channel %d: status: %s", c
->self
, s
);
427 shutdown(c
->sock
, SHUT_RDWR
);
428 channel_close_fds(c
);
429 buffer_free(&c
->input
);
430 buffer_free(&c
->output
);
431 buffer_free(&c
->extended
);
432 free(c
->remote_name
);
433 c
->remote_name
= NULL
;
436 free(c
->listening_addr
);
437 c
->listening_addr
= NULL
;
438 while ((cc
= TAILQ_FIRST(&c
->status_confirms
)) != NULL
) {
439 if (cc
->abandon_cb
!= NULL
)
440 cc
->abandon_cb(c
, cc
->ctx
);
441 TAILQ_REMOVE(&c
->status_confirms
, cc
, entry
);
442 explicit_bzero(cc
, sizeof(*cc
));
445 if (c
->filter_cleanup
!= NULL
&& c
->filter_ctx
!= NULL
)
446 c
->filter_cleanup(c
->self
, c
->filter_ctx
);
447 channels
[c
->self
] = NULL
;
452 channel_free_all(void)
456 for (i
= 0; i
< channels_alloc
; i
++)
457 if (channels
[i
] != NULL
)
458 channel_free(channels
[i
]);
462 * Closes the sockets/fds of all channels. This is used to close extra file
463 * descriptors after a fork.
466 channel_close_all(void)
470 for (i
= 0; i
< channels_alloc
; i
++)
471 if (channels
[i
] != NULL
)
472 channel_close_fds(channels
[i
]);
476 * Stop listening to channels.
479 channel_stop_listening(void)
484 for (i
= 0; i
< channels_alloc
; i
++) {
488 case SSH_CHANNEL_AUTH_SOCKET
:
489 case SSH_CHANNEL_PORT_LISTENER
:
490 case SSH_CHANNEL_RPORT_LISTENER
:
491 case SSH_CHANNEL_X11_LISTENER
:
492 case SSH_CHANNEL_UNIX_LISTENER
:
493 case SSH_CHANNEL_RUNIX_LISTENER
:
494 channel_close_fd(&c
->sock
);
503 * Returns true if no channel has too much buffered data, and false if one or
504 * more channel is overfull.
507 channel_not_very_much_buffered_data(void)
512 for (i
= 0; i
< channels_alloc
; i
++) {
514 if (c
!= NULL
&& c
->type
== SSH_CHANNEL_OPEN
) {
517 buffer_len(&c
->input
) > packet_get_maxsize()) {
518 debug2("channel %d: big input buffer %d",
519 c
->self
, buffer_len(&c
->input
));
523 if (buffer_len(&c
->output
) > packet_get_maxsize()) {
524 debug2("channel %d: big output buffer %u > %u",
525 c
->self
, buffer_len(&c
->output
),
526 packet_get_maxsize());
534 /* Returns true if any channel is still open. */
536 channel_still_open(void)
541 for (i
= 0; i
< channels_alloc
; i
++) {
546 case SSH_CHANNEL_X11_LISTENER
:
547 case SSH_CHANNEL_PORT_LISTENER
:
548 case SSH_CHANNEL_RPORT_LISTENER
:
549 case SSH_CHANNEL_MUX_LISTENER
:
550 case SSH_CHANNEL_CLOSED
:
551 case SSH_CHANNEL_AUTH_SOCKET
:
552 case SSH_CHANNEL_DYNAMIC
:
553 case SSH_CHANNEL_CONNECTING
:
554 case SSH_CHANNEL_ZOMBIE
:
555 case SSH_CHANNEL_ABANDONED
:
556 case SSH_CHANNEL_UNIX_LISTENER
:
557 case SSH_CHANNEL_RUNIX_LISTENER
:
559 case SSH_CHANNEL_LARVAL
:
561 fatal("cannot happen: SSH_CHANNEL_LARVAL");
563 case SSH_CHANNEL_OPENING
:
564 case SSH_CHANNEL_OPEN
:
565 case SSH_CHANNEL_X11_OPEN
:
566 case SSH_CHANNEL_MUX_CLIENT
:
568 case SSH_CHANNEL_INPUT_DRAINING
:
569 case SSH_CHANNEL_OUTPUT_DRAINING
:
571 fatal("cannot happen: OUT_DRAIN");
574 fatal("channel_still_open: bad channel type %d", c
->type
);
581 /* Returns the id of an open channel suitable for keepaliving */
583 channel_find_open(void)
588 for (i
= 0; i
< channels_alloc
; i
++) {
590 if (c
== NULL
|| c
->remote_id
< 0)
593 case SSH_CHANNEL_CLOSED
:
594 case SSH_CHANNEL_DYNAMIC
:
595 case SSH_CHANNEL_X11_LISTENER
:
596 case SSH_CHANNEL_PORT_LISTENER
:
597 case SSH_CHANNEL_RPORT_LISTENER
:
598 case SSH_CHANNEL_MUX_LISTENER
:
599 case SSH_CHANNEL_MUX_CLIENT
:
600 case SSH_CHANNEL_OPENING
:
601 case SSH_CHANNEL_CONNECTING
:
602 case SSH_CHANNEL_ZOMBIE
:
603 case SSH_CHANNEL_ABANDONED
:
604 case SSH_CHANNEL_UNIX_LISTENER
:
605 case SSH_CHANNEL_RUNIX_LISTENER
:
607 case SSH_CHANNEL_LARVAL
:
608 case SSH_CHANNEL_AUTH_SOCKET
:
609 case SSH_CHANNEL_OPEN
:
610 case SSH_CHANNEL_X11_OPEN
:
612 case SSH_CHANNEL_INPUT_DRAINING
:
613 case SSH_CHANNEL_OUTPUT_DRAINING
:
615 fatal("cannot happen: OUT_DRAIN");
618 fatal("channel_find_open: bad channel type %d", c
->type
);
627 * Returns a message describing the currently open forwarded connections,
628 * suitable for sending to the client. The message contains crlf pairs for
632 channel_open_message(void)
639 buffer_init(&buffer
);
640 snprintf(buf
, sizeof buf
, "The following connections are open:\r\n");
641 buffer_append(&buffer
, buf
, strlen(buf
));
642 for (i
= 0; i
< channels_alloc
; i
++) {
647 case SSH_CHANNEL_X11_LISTENER
:
648 case SSH_CHANNEL_PORT_LISTENER
:
649 case SSH_CHANNEL_RPORT_LISTENER
:
650 case SSH_CHANNEL_CLOSED
:
651 case SSH_CHANNEL_AUTH_SOCKET
:
652 case SSH_CHANNEL_ZOMBIE
:
653 case SSH_CHANNEL_ABANDONED
:
654 case SSH_CHANNEL_MUX_CLIENT
:
655 case SSH_CHANNEL_MUX_LISTENER
:
656 case SSH_CHANNEL_UNIX_LISTENER
:
657 case SSH_CHANNEL_RUNIX_LISTENER
:
659 case SSH_CHANNEL_LARVAL
:
660 case SSH_CHANNEL_OPENING
:
661 case SSH_CHANNEL_CONNECTING
:
662 case SSH_CHANNEL_DYNAMIC
:
663 case SSH_CHANNEL_OPEN
:
664 case SSH_CHANNEL_X11_OPEN
:
665 case SSH_CHANNEL_INPUT_DRAINING
:
666 case SSH_CHANNEL_OUTPUT_DRAINING
:
667 snprintf(buf
, sizeof buf
,
668 " #%d %.300s (t%d r%d i%u/%d o%u/%d fd %d/%d cc %d)\r\n",
669 c
->self
, c
->remote_name
,
670 c
->type
, c
->remote_id
,
671 c
->istate
, buffer_len(&c
->input
),
672 c
->ostate
, buffer_len(&c
->output
),
673 c
->rfd
, c
->wfd
, c
->ctl_chan
);
674 buffer_append(&buffer
, buf
, strlen(buf
));
677 fatal("channel_open_message: bad channel type %d", c
->type
);
681 buffer_append(&buffer
, "\0", 1);
682 cp
= xstrdup((char *)buffer_ptr(&buffer
));
683 buffer_free(&buffer
);
688 channel_send_open(int id
)
690 Channel
*c
= channel_lookup(id
);
693 logit("channel_send_open: %d: bad id", id
);
696 debug2("channel %d: send open", id
);
697 packet_start(SSH2_MSG_CHANNEL_OPEN
);
698 packet_put_cstring(c
->ctype
);
699 packet_put_int(c
->self
);
700 packet_put_int(c
->local_window
);
701 packet_put_int(c
->local_maxpacket
);
706 channel_request_start(int id
, char *service
, int wantconfirm
)
708 Channel
*c
= channel_lookup(id
);
711 logit("channel_request_start: %d: unknown channel id", id
);
714 debug2("channel %d: request %s confirm %d", id
, service
, wantconfirm
);
715 packet_start(SSH2_MSG_CHANNEL_REQUEST
);
716 packet_put_int(c
->remote_id
);
717 packet_put_cstring(service
);
718 packet_put_char(wantconfirm
);
722 channel_register_status_confirm(int id
, channel_confirm_cb
*cb
,
723 channel_confirm_abandon_cb
*abandon_cb
, void *ctx
)
725 struct channel_confirm
*cc
;
728 if ((c
= channel_lookup(id
)) == NULL
)
729 fatal("channel_register_expect: %d: bad id", id
);
731 cc
= xcalloc(1, sizeof(*cc
));
733 cc
->abandon_cb
= abandon_cb
;
735 TAILQ_INSERT_TAIL(&c
->status_confirms
, cc
, entry
);
739 channel_register_open_confirm(int id
, channel_open_fn
*fn
, void *ctx
)
741 Channel
*c
= channel_lookup(id
);
744 logit("channel_register_open_confirm: %d: bad id", id
);
747 c
->open_confirm
= fn
;
748 c
->open_confirm_ctx
= ctx
;
752 channel_register_cleanup(int id
, channel_callback_fn
*fn
, int do_close
)
754 Channel
*c
= channel_by_id(id
);
757 logit("channel_register_cleanup: %d: bad id", id
);
761 c
->detach_close
= do_close
;
765 channel_cancel_cleanup(int id
)
767 Channel
*c
= channel_by_id(id
);
770 logit("channel_cancel_cleanup: %d: bad id", id
);
773 c
->detach_user
= NULL
;
778 channel_register_filter(int id
, channel_infilter_fn
*ifn
,
779 channel_outfilter_fn
*ofn
, channel_filter_cleanup_fn
*cfn
, void *ctx
)
781 Channel
*c
= channel_lookup(id
);
784 logit("channel_register_filter: %d: bad id", id
);
787 c
->input_filter
= ifn
;
788 c
->output_filter
= ofn
;
790 c
->filter_cleanup
= cfn
;
794 channel_set_fds(int id
, int rfd
, int wfd
, int efd
,
795 int extusage
, int nonblock
, int is_tty
, u_int window_max
)
797 Channel
*c
= channel_lookup(id
);
799 if (c
== NULL
|| c
->type
!= SSH_CHANNEL_LARVAL
)
800 fatal("channel_activate for non-larval channel %d.", id
);
801 channel_register_fds(c
, rfd
, wfd
, efd
, extusage
, nonblock
, is_tty
);
802 c
->type
= SSH_CHANNEL_OPEN
;
803 c
->local_window
= c
->local_window_max
= window_max
;
804 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
805 packet_put_int(c
->remote_id
);
806 packet_put_int(c
->local_window
);
811 * 'channel_pre*' are called just before select() to add any bits relevant to
812 * channels in the select bitmasks.
815 * 'channel_post*': perform any appropriate operations for channels which
816 * have events pending.
818 typedef void chan_fn(Channel
*c
, fd_set
*readset
, fd_set
*writeset
);
819 chan_fn
*channel_pre
[SSH_CHANNEL_MAX_TYPE
];
820 chan_fn
*channel_post
[SSH_CHANNEL_MAX_TYPE
];
824 channel_pre_listener(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
826 FD_SET(c
->sock
, readset
);
831 channel_pre_connecting(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
833 debug3("channel %d: waiting for connection", c
->self
);
834 FD_SET(c
->sock
, writeset
);
838 channel_pre_open_13(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
840 if (buffer_len(&c
->input
) < packet_get_maxsize())
841 FD_SET(c
->sock
, readset
);
842 if (buffer_len(&c
->output
) > 0)
843 FD_SET(c
->sock
, writeset
);
847 channel_pre_open(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
849 u_int limit
= compat20
? c
->remote_window
: packet_get_maxsize();
851 if (c
->istate
== CHAN_INPUT_OPEN
&&
853 buffer_len(&c
->input
) < limit
&&
854 buffer_check_alloc(&c
->input
, CHAN_RBUF
))
855 FD_SET(c
->rfd
, readset
);
856 if (c
->ostate
== CHAN_OUTPUT_OPEN
||
857 c
->ostate
== CHAN_OUTPUT_WAIT_DRAIN
) {
858 if (buffer_len(&c
->output
) > 0) {
859 FD_SET(c
->wfd
, writeset
);
860 } else if (c
->ostate
== CHAN_OUTPUT_WAIT_DRAIN
) {
861 if (CHANNEL_EFD_OUTPUT_ACTIVE(c
))
862 debug2("channel %d: obuf_empty delayed efd %d/(%d)",
863 c
->self
, c
->efd
, buffer_len(&c
->extended
));
868 /** XXX check close conditions, too */
869 if (compat20
&& c
->efd
!= -1 &&
870 !(c
->istate
== CHAN_INPUT_CLOSED
&& c
->ostate
== CHAN_OUTPUT_CLOSED
)) {
871 if (c
->extended_usage
== CHAN_EXTENDED_WRITE
&&
872 buffer_len(&c
->extended
) > 0)
873 FD_SET(c
->efd
, writeset
);
874 else if (c
->efd
!= -1 && !(c
->flags
& CHAN_EOF_SENT
) &&
875 (c
->extended_usage
== CHAN_EXTENDED_READ
||
876 c
->extended_usage
== CHAN_EXTENDED_IGNORE
) &&
877 buffer_len(&c
->extended
) < c
->remote_window
)
878 FD_SET(c
->efd
, readset
);
880 /* XXX: What about efd? races? */
885 channel_pre_input_draining(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
887 if (buffer_len(&c
->input
) == 0) {
888 packet_start(SSH_MSG_CHANNEL_CLOSE
);
889 packet_put_int(c
->remote_id
);
891 c
->type
= SSH_CHANNEL_CLOSED
;
892 debug2("channel %d: closing after input drain.", c
->self
);
898 channel_pre_output_draining(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
900 if (buffer_len(&c
->output
) == 0)
903 FD_SET(c
->sock
, writeset
);
907 * This is a special state for X11 authentication spoofing. An opened X11
908 * connection (when authentication spoofing is being done) remains in this
909 * state until the first packet has been completely read. The authentication
910 * data in that packet is then substituted by the real data if it matches the
911 * fake data, and the channel is put into normal mode.
912 * XXX All this happens at the client side.
913 * Returns: 0 = need more data, -1 = wrong cookie, 1 = ok
916 x11_open_helper(Buffer
*b
)
919 u_int proto_len
, data_len
;
921 /* Is this being called after the refusal deadline? */
922 if (x11_refuse_time
!= 0 && (u_int
)monotime() >= x11_refuse_time
) {
923 verbose("Rejected X11 connection after ForwardX11Timeout "
928 /* Check if the fixed size part of the packet is in buffer. */
929 if (buffer_len(b
) < 12)
932 /* Parse the lengths of variable-length fields. */
934 if (ucp
[0] == 0x42) { /* Byte order MSB first. */
935 proto_len
= 256 * ucp
[6] + ucp
[7];
936 data_len
= 256 * ucp
[8] + ucp
[9];
937 } else if (ucp
[0] == 0x6c) { /* Byte order LSB first. */
938 proto_len
= ucp
[6] + 256 * ucp
[7];
939 data_len
= ucp
[8] + 256 * ucp
[9];
941 debug2("Initial X11 packet contains bad byte order byte: 0x%x",
946 /* Check if the whole packet is in buffer. */
948 12 + ((proto_len
+ 3) & ~3) + ((data_len
+ 3) & ~3))
951 /* Check if authentication protocol matches. */
952 if (proto_len
!= strlen(x11_saved_proto
) ||
953 memcmp(ucp
+ 12, x11_saved_proto
, proto_len
) != 0) {
954 debug2("X11 connection uses different authentication protocol.");
957 /* Check if authentication data matches our fake data. */
958 if (data_len
!= x11_fake_data_len
||
959 timingsafe_bcmp(ucp
+ 12 + ((proto_len
+ 3) & ~3),
960 x11_fake_data
, x11_fake_data_len
) != 0) {
961 debug2("X11 auth data does not match fake data.");
964 /* Check fake data length */
965 if (x11_fake_data_len
!= x11_saved_data_len
) {
966 error("X11 fake_data_len %d != saved_data_len %d",
967 x11_fake_data_len
, x11_saved_data_len
);
971 * Received authentication protocol and data match
972 * our fake data. Substitute the fake data with real
975 memcpy(ucp
+ 12 + ((proto_len
+ 3) & ~3),
976 x11_saved_data
, x11_saved_data_len
);
981 channel_pre_x11_open_13(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
983 int ret
= x11_open_helper(&c
->output
);
986 /* Start normal processing for the channel. */
987 c
->type
= SSH_CHANNEL_OPEN
;
988 channel_pre_open_13(c
, readset
, writeset
);
989 } else if (ret
== -1) {
991 * We have received an X11 connection that has bad
992 * authentication information.
994 logit("X11 connection rejected because of wrong authentication.");
995 buffer_clear(&c
->input
);
996 buffer_clear(&c
->output
);
997 channel_close_fd(&c
->sock
);
999 c
->type
= SSH_CHANNEL_CLOSED
;
1000 packet_start(SSH_MSG_CHANNEL_CLOSE
);
1001 packet_put_int(c
->remote_id
);
1007 channel_pre_x11_open(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1009 int ret
= x11_open_helper(&c
->output
);
1011 /* c->force_drain = 1; */
1014 c
->type
= SSH_CHANNEL_OPEN
;
1015 channel_pre_open(c
, readset
, writeset
);
1016 } else if (ret
== -1) {
1017 logit("X11 connection rejected because of wrong authentication.");
1018 debug2("X11 rejected %d i%d/o%d", c
->self
, c
->istate
, c
->ostate
);
1019 chan_read_failed(c
);
1020 buffer_clear(&c
->input
);
1022 buffer_clear(&c
->output
);
1023 /* for proto v1, the peer will send an IEOF */
1025 chan_write_failed(c
);
1027 c
->type
= SSH_CHANNEL_OPEN
;
1028 debug2("X11 closed %d i%d/o%d", c
->self
, c
->istate
, c
->ostate
);
1033 channel_pre_mux_client(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1035 if (c
->istate
== CHAN_INPUT_OPEN
&& !c
->mux_pause
&&
1036 buffer_check_alloc(&c
->input
, CHAN_RBUF
))
1037 FD_SET(c
->rfd
, readset
);
1038 if (c
->istate
== CHAN_INPUT_WAIT_DRAIN
) {
1039 /* clear buffer immediately (discard any partial packet) */
1040 buffer_clear(&c
->input
);
1042 /* Start output drain. XXX just kill chan? */
1043 chan_rcvd_oclose(c
);
1045 if (c
->ostate
== CHAN_OUTPUT_OPEN
||
1046 c
->ostate
== CHAN_OUTPUT_WAIT_DRAIN
) {
1047 if (buffer_len(&c
->output
) > 0)
1048 FD_SET(c
->wfd
, writeset
);
1049 else if (c
->ostate
== CHAN_OUTPUT_WAIT_DRAIN
)
1054 /* try to decode a socks4 header */
1057 channel_decode_socks4(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1060 u_int len
, have
, i
, found
, need
;
1065 u_int16_t dest_port
;
1066 struct in_addr dest_addr
;
1069 debug2("channel %d: decode socks4", c
->self
);
1071 have
= buffer_len(&c
->input
);
1072 len
= sizeof(s4_req
);
1075 p
= (char *)buffer_ptr(&c
->input
);
1078 /* SOCKS4A uses an invalid IP address 0.0.0.x */
1079 if (p
[4] == 0 && p
[5] == 0 && p
[6] == 0 && p
[7] != 0) {
1080 debug2("channel %d: socks4a request", c
->self
);
1081 /* ... and needs an extra string (the hostname) */
1084 /* Check for terminating NUL on the string(s) */
1085 for (found
= 0, i
= len
; i
< have
; i
++) {
1092 /* the peer is probably sending garbage */
1093 debug("channel %d: decode socks4: too long",
1100 buffer_get(&c
->input
, (char *)&s4_req
.version
, 1);
1101 buffer_get(&c
->input
, (char *)&s4_req
.command
, 1);
1102 buffer_get(&c
->input
, (char *)&s4_req
.dest_port
, 2);
1103 buffer_get(&c
->input
, (char *)&s4_req
.dest_addr
, 4);
1104 have
= buffer_len(&c
->input
);
1105 p
= (char *)buffer_ptr(&c
->input
);
1106 if (memchr(p
, '\0', have
) == NULL
)
1107 fatal("channel %d: decode socks4: user not nul terminated",
1110 debug2("channel %d: decode socks4: user %s/%d", c
->self
, p
, len
);
1111 len
++; /* trailing '\0' */
1113 fatal("channel %d: decode socks4: len %d > have %d",
1114 c
->self
, len
, have
);
1115 strlcpy(username
, p
, sizeof(username
));
1116 buffer_consume(&c
->input
, len
);
1120 if (need
== 1) { /* SOCKS4: one string */
1121 host
= inet_ntoa(s4_req
.dest_addr
);
1122 c
->path
= xstrdup(host
);
1123 } else { /* SOCKS4A: two strings */
1124 have
= buffer_len(&c
->input
);
1125 p
= (char *)buffer_ptr(&c
->input
);
1127 debug2("channel %d: decode socks4a: host %s/%d",
1129 len
++; /* trailing '\0' */
1131 fatal("channel %d: decode socks4a: len %d > have %d",
1132 c
->self
, len
, have
);
1133 if (len
> NI_MAXHOST
) {
1134 error("channel %d: hostname \"%.100s\" too long",
1138 c
->path
= xstrdup(p
);
1139 buffer_consume(&c
->input
, len
);
1141 c
->host_port
= ntohs(s4_req
.dest_port
);
1143 debug2("channel %d: dynamic request: socks4 host %s port %u command %u",
1144 c
->self
, c
->path
, c
->host_port
, s4_req
.command
);
1146 if (s4_req
.command
!= 1) {
1147 debug("channel %d: cannot handle: %s cn %d",
1148 c
->self
, need
== 1 ? "SOCKS4" : "SOCKS4A", s4_req
.command
);
1151 s4_rsp
.version
= 0; /* vn: 0 for reply */
1152 s4_rsp
.command
= 90; /* cd: req granted */
1153 s4_rsp
.dest_port
= 0; /* ignored */
1154 s4_rsp
.dest_addr
.s_addr
= INADDR_ANY
; /* ignored */
1155 buffer_append(&c
->output
, &s4_rsp
, sizeof(s4_rsp
));
1159 /* try to decode a socks5 header */
1160 #define SSH_SOCKS5_AUTHDONE 0x1000
1161 #define SSH_SOCKS5_NOAUTH 0x00
1162 #define SSH_SOCKS5_IPV4 0x01
1163 #define SSH_SOCKS5_DOMAIN 0x03
1164 #define SSH_SOCKS5_IPV6 0x04
1165 #define SSH_SOCKS5_CONNECT 0x01
1166 #define SSH_SOCKS5_SUCCESS 0x00
1170 channel_decode_socks5(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1178 u_int16_t dest_port
;
1179 char dest_addr
[255+1], ntop
[INET6_ADDRSTRLEN
];
1181 u_int have
, need
, i
, found
, nmethods
, addrlen
, af
;
1183 debug2("channel %d: decode socks5", c
->self
);
1184 p
= buffer_ptr(&c
->input
);
1187 have
= buffer_len(&c
->input
);
1188 if (!(c
->flags
& SSH_SOCKS5_AUTHDONE
)) {
1189 /* format: ver | nmethods | methods */
1193 if (have
< nmethods
+ 2)
1195 /* look for method: "NO AUTHENTICATION REQUIRED" */
1196 for (found
= 0, i
= 2; i
< nmethods
+ 2; i
++) {
1197 if (p
[i
] == SSH_SOCKS5_NOAUTH
) {
1203 debug("channel %d: method SSH_SOCKS5_NOAUTH not found",
1207 buffer_consume(&c
->input
, nmethods
+ 2);
1208 buffer_put_char(&c
->output
, 0x05); /* version */
1209 buffer_put_char(&c
->output
, SSH_SOCKS5_NOAUTH
); /* method */
1210 FD_SET(c
->sock
, writeset
);
1211 c
->flags
|= SSH_SOCKS5_AUTHDONE
;
1212 debug2("channel %d: socks5 auth done", c
->self
);
1213 return 0; /* need more */
1215 debug2("channel %d: socks5 post auth", c
->self
);
1216 if (have
< sizeof(s5_req
)+1)
1217 return 0; /* need more */
1218 memcpy(&s5_req
, p
, sizeof(s5_req
));
1219 if (s5_req
.version
!= 0x05 ||
1220 s5_req
.command
!= SSH_SOCKS5_CONNECT
||
1221 s5_req
.reserved
!= 0x00) {
1222 debug2("channel %d: only socks5 connect supported", c
->self
);
1225 switch (s5_req
.atyp
){
1226 case SSH_SOCKS5_IPV4
:
1230 case SSH_SOCKS5_DOMAIN
:
1231 addrlen
= p
[sizeof(s5_req
)];
1234 case SSH_SOCKS5_IPV6
:
1239 debug2("channel %d: bad socks5 atyp %d", c
->self
, s5_req
.atyp
);
1242 need
= sizeof(s5_req
) + addrlen
+ 2;
1243 if (s5_req
.atyp
== SSH_SOCKS5_DOMAIN
)
1247 buffer_consume(&c
->input
, sizeof(s5_req
));
1248 if (s5_req
.atyp
== SSH_SOCKS5_DOMAIN
)
1249 buffer_consume(&c
->input
, 1); /* host string length */
1250 buffer_get(&c
->input
, &dest_addr
, addrlen
);
1251 buffer_get(&c
->input
, (char *)&dest_port
, 2);
1252 dest_addr
[addrlen
] = '\0';
1255 if (s5_req
.atyp
== SSH_SOCKS5_DOMAIN
) {
1256 if (addrlen
>= NI_MAXHOST
) {
1257 error("channel %d: dynamic request: socks5 hostname "
1258 "\"%.100s\" too long", c
->self
, dest_addr
);
1261 c
->path
= xstrdup(dest_addr
);
1263 if (inet_ntop(af
, dest_addr
, ntop
, sizeof(ntop
)) == NULL
)
1265 c
->path
= xstrdup(ntop
);
1267 c
->host_port
= ntohs(dest_port
);
1269 debug2("channel %d: dynamic request: socks5 host %s port %u command %u",
1270 c
->self
, c
->path
, c
->host_port
, s5_req
.command
);
1272 s5_rsp
.version
= 0x05;
1273 s5_rsp
.command
= SSH_SOCKS5_SUCCESS
;
1274 s5_rsp
.reserved
= 0; /* ignored */
1275 s5_rsp
.atyp
= SSH_SOCKS5_IPV4
;
1276 dest_port
= 0; /* ignored */
1278 buffer_append(&c
->output
, &s5_rsp
, sizeof(s5_rsp
));
1279 buffer_put_int(&c
->output
, ntohl(INADDR_ANY
)); /* bind address */
1280 buffer_append(&c
->output
, &dest_port
, sizeof(dest_port
));
1285 channel_connect_stdio_fwd(const char *host_to_connect
, u_short port_to_connect
,
1290 debug("channel_connect_stdio_fwd %s:%d", host_to_connect
,
1293 c
= channel_new("stdio-forward", SSH_CHANNEL_OPENING
, in
, out
,
1294 -1, CHAN_TCP_WINDOW_DEFAULT
, CHAN_TCP_PACKET_DEFAULT
,
1295 0, "stdio-forward", /*nonblock*/0);
1297 c
->path
= xstrdup(host_to_connect
);
1298 c
->host_port
= port_to_connect
;
1299 c
->listening_port
= 0;
1302 channel_register_fds(c
, in
, out
, -1, 0, 1, 0);
1303 port_open_helper(c
, "direct-tcpip");
1308 /* dynamic port forwarding */
1310 channel_pre_dynamic(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1316 have
= buffer_len(&c
->input
);
1317 debug2("channel %d: pre_dynamic: have %d", c
->self
, have
);
1318 /* buffer_dump(&c->input); */
1319 /* check if the fixed size part of the packet is in buffer. */
1322 FD_SET(c
->sock
, readset
);
1325 /* try to guess the protocol */
1326 p
= buffer_ptr(&c
->input
);
1329 ret
= channel_decode_socks4(c
, readset
, writeset
);
1332 ret
= channel_decode_socks5(c
, readset
, writeset
);
1340 } else if (ret
== 0) {
1341 debug2("channel %d: pre_dynamic: need more", c
->self
);
1343 FD_SET(c
->sock
, readset
);
1345 /* switch to the next state */
1346 c
->type
= SSH_CHANNEL_OPENING
;
1347 port_open_helper(c
, "direct-tcpip");
1351 /* This is our fake X11 server socket. */
1354 channel_post_x11_listener(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1357 struct sockaddr_storage addr
;
1358 int newsock
, oerrno
;
1360 char buf
[16384], *remote_ipaddr
;
1363 if (FD_ISSET(c
->sock
, readset
)) {
1364 debug("X11 connection requested.");
1365 addrlen
= sizeof(addr
);
1366 newsock
= accept(c
->sock
, (struct sockaddr
*)&addr
, &addrlen
);
1367 if (c
->single_connection
) {
1369 debug2("single_connection: closing X11 listener.");
1370 channel_close_fd(&c
->sock
);
1375 if (errno
!= EINTR
&& errno
!= EWOULDBLOCK
&&
1376 errno
!= ECONNABORTED
)
1377 error("accept: %.100s", strerror(errno
));
1378 if (errno
== EMFILE
|| errno
== ENFILE
)
1379 c
->notbefore
= monotime() + 1;
1382 set_nodelay(newsock
);
1383 remote_ipaddr
= get_peer_ipaddr(newsock
);
1384 remote_port
= get_peer_port(newsock
);
1385 snprintf(buf
, sizeof buf
, "X11 connection from %.200s port %d",
1386 remote_ipaddr
, remote_port
);
1388 nc
= channel_new("accepted x11 socket",
1389 SSH_CHANNEL_OPENING
, newsock
, newsock
, -1,
1390 c
->local_window_max
, c
->local_maxpacket
, 0, buf
, 1);
1392 packet_start(SSH2_MSG_CHANNEL_OPEN
);
1393 packet_put_cstring("x11");
1394 packet_put_int(nc
->self
);
1395 packet_put_int(nc
->local_window_max
);
1396 packet_put_int(nc
->local_maxpacket
);
1397 /* originator ipaddr and port */
1398 packet_put_cstring(remote_ipaddr
);
1399 if (datafellows
& SSH_BUG_X11FWD
) {
1400 debug2("ssh2 x11 bug compat mode");
1402 packet_put_int(remote_port
);
1406 packet_start(SSH_SMSG_X11_OPEN
);
1407 packet_put_int(nc
->self
);
1408 if (packet_get_protocol_flags() &
1409 SSH_PROTOFLAG_HOST_IN_FWD_OPEN
)
1410 packet_put_cstring(buf
);
1413 free(remote_ipaddr
);
1418 port_open_helper(Channel
*c
, char *rtype
)
1421 char *local_ipaddr
= get_local_ipaddr(c
->sock
);
1422 int local_port
= c
->sock
== -1 ? 65536 : get_local_port(c
->sock
);
1423 char *remote_ipaddr
= get_peer_ipaddr(c
->sock
);
1424 int remote_port
= get_peer_port(c
->sock
);
1426 if (remote_port
== -1) {
1427 /* Fake addr/port to appease peers that validate it (Tectia) */
1428 free(remote_ipaddr
);
1429 remote_ipaddr
= xstrdup("127.0.0.1");
1430 remote_port
= 65535;
1433 snprintf(buf
, sizeof buf
,
1434 "%s: listening port %d for %.100s port %d, "
1435 "connect from %.200s port %d to %.100s port %d",
1436 rtype
, c
->listening_port
, c
->path
, c
->host_port
,
1437 remote_ipaddr
, remote_port
, local_ipaddr
, local_port
);
1439 free(c
->remote_name
);
1440 c
->remote_name
= xstrdup(buf
);
1443 packet_start(SSH2_MSG_CHANNEL_OPEN
);
1444 packet_put_cstring(rtype
);
1445 packet_put_int(c
->self
);
1446 packet_put_int(c
->local_window_max
);
1447 packet_put_int(c
->local_maxpacket
);
1448 if (strcmp(rtype
, "direct-tcpip") == 0) {
1449 /* target host, port */
1450 packet_put_cstring(c
->path
);
1451 packet_put_int(c
->host_port
);
1452 } else if (strcmp(rtype
, "direct-streamlocal@openssh.com") == 0) {
1454 packet_put_cstring(c
->path
);
1455 } else if (strcmp(rtype
, "forwarded-streamlocal@openssh.com") == 0) {
1457 packet_put_cstring(c
->path
);
1459 /* listen address, port */
1460 packet_put_cstring(c
->path
);
1461 packet_put_int(local_port
);
1463 if (strcmp(rtype
, "forwarded-streamlocal@openssh.com") == 0) {
1464 /* reserved for future owner/mode info */
1465 packet_put_cstring("");
1467 /* originator host and port */
1468 packet_put_cstring(remote_ipaddr
);
1469 packet_put_int((u_int
)remote_port
);
1473 packet_start(SSH_MSG_PORT_OPEN
);
1474 packet_put_int(c
->self
);
1475 packet_put_cstring(c
->path
);
1476 packet_put_int(c
->host_port
);
1477 if (packet_get_protocol_flags() &
1478 SSH_PROTOFLAG_HOST_IN_FWD_OPEN
)
1479 packet_put_cstring(c
->remote_name
);
1482 free(remote_ipaddr
);
1487 channel_set_reuseaddr(int fd
)
1492 * Set socket options.
1493 * Allow local port reuse in TIME_WAIT.
1495 if (setsockopt(fd
, SOL_SOCKET
, SO_REUSEADDR
, &on
, sizeof(on
)) == -1)
1496 error("setsockopt SO_REUSEADDR fd %d: %s", fd
, strerror(errno
));
1500 channel_set_x11_refuse_time(u_int refuse_time
)
1502 x11_refuse_time
= refuse_time
;
1506 * This socket is listening for connections to a forwarded TCP/IP port.
1510 channel_post_port_listener(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1513 struct sockaddr_storage addr
;
1514 int newsock
, nextstate
;
1518 if (FD_ISSET(c
->sock
, readset
)) {
1519 debug("Connection to port %d forwarding "
1520 "to %.100s port %d requested.",
1521 c
->listening_port
, c
->path
, c
->host_port
);
1523 if (c
->type
== SSH_CHANNEL_RPORT_LISTENER
) {
1524 nextstate
= SSH_CHANNEL_OPENING
;
1525 rtype
= "forwarded-tcpip";
1526 } else if (c
->type
== SSH_CHANNEL_RUNIX_LISTENER
) {
1527 nextstate
= SSH_CHANNEL_OPENING
;
1528 rtype
= "forwarded-streamlocal@openssh.com";
1529 } else if (c
->host_port
== PORT_STREAMLOCAL
) {
1530 nextstate
= SSH_CHANNEL_OPENING
;
1531 rtype
= "direct-streamlocal@openssh.com";
1532 } else if (c
->host_port
== 0) {
1533 nextstate
= SSH_CHANNEL_DYNAMIC
;
1534 rtype
= "dynamic-tcpip";
1536 nextstate
= SSH_CHANNEL_OPENING
;
1537 rtype
= "direct-tcpip";
1540 addrlen
= sizeof(addr
);
1541 newsock
= accept(c
->sock
, (struct sockaddr
*)&addr
, &addrlen
);
1543 if (errno
!= EINTR
&& errno
!= EWOULDBLOCK
&&
1544 errno
!= ECONNABORTED
)
1545 error("accept: %.100s", strerror(errno
));
1546 if (errno
== EMFILE
|| errno
== ENFILE
)
1547 c
->notbefore
= monotime() + 1;
1550 if (c
->host_port
!= PORT_STREAMLOCAL
)
1551 set_nodelay(newsock
);
1552 nc
= channel_new(rtype
, nextstate
, newsock
, newsock
, -1,
1553 c
->local_window_max
, c
->local_maxpacket
, 0, rtype
, 1);
1554 nc
->listening_port
= c
->listening_port
;
1555 nc
->host_port
= c
->host_port
;
1556 if (c
->path
!= NULL
)
1557 nc
->path
= xstrdup(c
->path
);
1559 if (nextstate
!= SSH_CHANNEL_DYNAMIC
)
1560 port_open_helper(nc
, rtype
);
1565 * This is the authentication agent socket listening for connections from
1570 channel_post_auth_listener(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1574 struct sockaddr_storage addr
;
1577 if (FD_ISSET(c
->sock
, readset
)) {
1578 addrlen
= sizeof(addr
);
1579 newsock
= accept(c
->sock
, (struct sockaddr
*)&addr
, &addrlen
);
1581 error("accept from auth socket: %.100s",
1583 if (errno
== EMFILE
|| errno
== ENFILE
)
1584 c
->notbefore
= monotime() + 1;
1587 nc
= channel_new("accepted auth socket",
1588 SSH_CHANNEL_OPENING
, newsock
, newsock
, -1,
1589 c
->local_window_max
, c
->local_maxpacket
,
1590 0, "accepted auth socket", 1);
1592 packet_start(SSH2_MSG_CHANNEL_OPEN
);
1593 packet_put_cstring("auth-agent@openssh.com");
1594 packet_put_int(nc
->self
);
1595 packet_put_int(c
->local_window_max
);
1596 packet_put_int(c
->local_maxpacket
);
1598 packet_start(SSH_SMSG_AGENT_OPEN
);
1599 packet_put_int(nc
->self
);
1607 channel_post_connecting(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1610 socklen_t sz
= sizeof(err
);
1612 if (FD_ISSET(c
->sock
, writeset
)) {
1613 if (getsockopt(c
->sock
, SOL_SOCKET
, SO_ERROR
, &err
, &sz
) < 0) {
1615 error("getsockopt SO_ERROR failed");
1618 debug("channel %d: connected to %s port %d",
1619 c
->self
, c
->connect_ctx
.host
, c
->connect_ctx
.port
);
1620 channel_connect_ctx_free(&c
->connect_ctx
);
1621 c
->type
= SSH_CHANNEL_OPEN
;
1623 packet_start(SSH2_MSG_CHANNEL_OPEN_CONFIRMATION
);
1624 packet_put_int(c
->remote_id
);
1625 packet_put_int(c
->self
);
1626 packet_put_int(c
->local_window
);
1627 packet_put_int(c
->local_maxpacket
);
1629 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION
);
1630 packet_put_int(c
->remote_id
);
1631 packet_put_int(c
->self
);
1634 debug("channel %d: connection failed: %s",
1635 c
->self
, strerror(err
));
1636 /* Try next address, if any */
1637 if ((sock
= connect_next(&c
->connect_ctx
)) > 0) {
1639 c
->sock
= c
->rfd
= c
->wfd
= sock
;
1640 channel_max_fd
= channel_find_maxfd();
1643 /* Exhausted all addresses */
1644 error("connect_to %.100s port %d: failed.",
1645 c
->connect_ctx
.host
, c
->connect_ctx
.port
);
1646 channel_connect_ctx_free(&c
->connect_ctx
);
1648 packet_start(SSH2_MSG_CHANNEL_OPEN_FAILURE
);
1649 packet_put_int(c
->remote_id
);
1650 packet_put_int(SSH2_OPEN_CONNECT_FAILED
);
1651 if (!(datafellows
& SSH_BUG_OPENFAILURE
)) {
1652 packet_put_cstring(strerror(err
));
1653 packet_put_cstring("");
1656 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE
);
1657 packet_put_int(c
->remote_id
);
1667 channel_handle_rfd(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1669 char buf
[CHAN_RBUF
];
1672 force
= c
->isatty
&& c
->detach_close
&& c
->istate
!= CHAN_INPUT_CLOSED
;
1673 if (c
->rfd
!= -1 && (force
|| FD_ISSET(c
->rfd
, readset
))) {
1675 len
= read(c
->rfd
, buf
, sizeof(buf
));
1676 if (len
< 0 && (errno
== EINTR
||
1677 ((errno
== EAGAIN
|| errno
== EWOULDBLOCK
) && !force
)))
1679 #ifndef PTY_ZEROREAD
1682 if ((!c
->isatty
&& len
<= 0) ||
1683 (c
->isatty
&& (len
< 0 || (len
== 0 && errno
!= 0)))) {
1685 debug2("channel %d: read<=0 rfd %d len %d",
1686 c
->self
, c
->rfd
, len
);
1687 if (c
->type
!= SSH_CHANNEL_OPEN
) {
1688 debug2("channel %d: not open", c
->self
);
1691 } else if (compat13
) {
1692 buffer_clear(&c
->output
);
1693 c
->type
= SSH_CHANNEL_INPUT_DRAINING
;
1694 debug2("channel %d: input draining.", c
->self
);
1696 chan_read_failed(c
);
1700 if (c
->input_filter
!= NULL
) {
1701 if (c
->input_filter(c
, buf
, len
) == -1) {
1702 debug2("channel %d: filter stops", c
->self
);
1703 chan_read_failed(c
);
1705 } else if (c
->datagram
) {
1706 buffer_put_string(&c
->input
, buf
, len
);
1708 buffer_append(&c
->input
, buf
, len
);
1716 channel_handle_wfd(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1719 u_char
*data
= NULL
, *buf
;
1720 u_int dlen
, olen
= 0;
1723 /* Send buffered output data to the socket. */
1725 FD_ISSET(c
->wfd
, writeset
) &&
1726 buffer_len(&c
->output
) > 0) {
1727 olen
= buffer_len(&c
->output
);
1728 if (c
->output_filter
!= NULL
) {
1729 if ((buf
= c
->output_filter(c
, &data
, &dlen
)) == NULL
) {
1730 debug2("channel %d: filter stops", c
->self
);
1731 if (c
->type
!= SSH_CHANNEL_OPEN
)
1734 chan_write_failed(c
);
1737 } else if (c
->datagram
) {
1738 buf
= data
= buffer_get_string(&c
->output
, &dlen
);
1740 buf
= data
= buffer_ptr(&c
->output
);
1741 dlen
= buffer_len(&c
->output
);
1745 /* ignore truncated writes, datagrams might get lost */
1746 len
= write(c
->wfd
, buf
, dlen
);
1748 if (len
< 0 && (errno
== EINTR
|| errno
== EAGAIN
||
1749 errno
== EWOULDBLOCK
))
1752 if (c
->type
!= SSH_CHANNEL_OPEN
)
1755 chan_write_failed(c
);
1761 /* XXX: Later AIX versions can't push as much data to tty */
1762 if (compat20
&& c
->wfd_isatty
)
1763 dlen
= MIN(dlen
, 8*1024);
1766 len
= write(c
->wfd
, buf
, dlen
);
1768 (errno
== EINTR
|| errno
== EAGAIN
|| errno
== EWOULDBLOCK
))
1771 if (c
->type
!= SSH_CHANNEL_OPEN
) {
1772 debug2("channel %d: not open", c
->self
);
1775 } else if (compat13
) {
1776 buffer_clear(&c
->output
);
1777 debug2("channel %d: input draining.", c
->self
);
1778 c
->type
= SSH_CHANNEL_INPUT_DRAINING
;
1780 chan_write_failed(c
);
1784 #ifndef BROKEN_TCGETATTR_ICANON
1785 if (compat20
&& c
->isatty
&& dlen
>= 1 && buf
[0] != '\r') {
1786 if (tcgetattr(c
->wfd
, &tio
) == 0 &&
1787 !(tio
.c_lflag
& ECHO
) && (tio
.c_lflag
& ICANON
)) {
1789 * Simulate echo to reduce the impact of
1790 * traffic analysis. We need to match the
1791 * size of a SSH2_MSG_CHANNEL_DATA message
1792 * (4 byte channel id + buf)
1794 packet_send_ignore(4 + len
);
1799 buffer_consume(&c
->output
, len
);
1802 if (compat20
&& olen
> 0)
1803 c
->local_consumed
+= olen
- buffer_len(&c
->output
);
1808 channel_handle_efd(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1810 char buf
[CHAN_RBUF
];
1813 /** XXX handle drain efd, too */
1815 if (c
->extended_usage
== CHAN_EXTENDED_WRITE
&&
1816 FD_ISSET(c
->efd
, writeset
) &&
1817 buffer_len(&c
->extended
) > 0) {
1818 len
= write(c
->efd
, buffer_ptr(&c
->extended
),
1819 buffer_len(&c
->extended
));
1820 debug2("channel %d: written %d to efd %d",
1821 c
->self
, len
, c
->efd
);
1822 if (len
< 0 && (errno
== EINTR
|| errno
== EAGAIN
||
1823 errno
== EWOULDBLOCK
))
1826 debug2("channel %d: closing write-efd %d",
1828 channel_close_fd(&c
->efd
);
1830 buffer_consume(&c
->extended
, len
);
1831 c
->local_consumed
+= len
;
1833 } else if (c
->efd
!= -1 &&
1834 (c
->extended_usage
== CHAN_EXTENDED_READ
||
1835 c
->extended_usage
== CHAN_EXTENDED_IGNORE
) &&
1836 (c
->detach_close
|| FD_ISSET(c
->efd
, readset
))) {
1837 len
= read(c
->efd
, buf
, sizeof(buf
));
1838 debug2("channel %d: read %d from efd %d",
1839 c
->self
, len
, c
->efd
);
1840 if (len
< 0 && (errno
== EINTR
|| ((errno
== EAGAIN
||
1841 errno
== EWOULDBLOCK
) && !c
->detach_close
)))
1844 debug2("channel %d: closing read-efd %d",
1846 channel_close_fd(&c
->efd
);
1848 if (c
->extended_usage
== CHAN_EXTENDED_IGNORE
) {
1849 debug3("channel %d: discard efd",
1852 buffer_append(&c
->extended
, buf
, len
);
1860 channel_check_window(Channel
*c
)
1862 if (c
->type
== SSH_CHANNEL_OPEN
&&
1863 !(c
->flags
& (CHAN_CLOSE_SENT
|CHAN_CLOSE_RCVD
)) &&
1864 ((c
->local_window_max
- c
->local_window
>
1865 c
->local_maxpacket
*3) ||
1866 c
->local_window
< c
->local_window_max
/2) &&
1867 c
->local_consumed
> 0) {
1868 packet_start(SSH2_MSG_CHANNEL_WINDOW_ADJUST
);
1869 packet_put_int(c
->remote_id
);
1870 packet_put_int(c
->local_consumed
);
1872 debug2("channel %d: window %d sent adjust %d",
1873 c
->self
, c
->local_window
,
1875 c
->local_window
+= c
->local_consumed
;
1876 c
->local_consumed
= 0;
1882 channel_post_open(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1884 channel_handle_rfd(c
, readset
, writeset
);
1885 channel_handle_wfd(c
, readset
, writeset
);
1888 channel_handle_efd(c
, readset
, writeset
);
1889 channel_check_window(c
);
1893 read_mux(Channel
*c
, u_int need
)
1895 char buf
[CHAN_RBUF
];
1899 if (buffer_len(&c
->input
) < need
) {
1900 rlen
= need
- buffer_len(&c
->input
);
1901 len
= read(c
->rfd
, buf
, MIN(rlen
, CHAN_RBUF
));
1902 if (len
< 0 && (errno
== EINTR
|| errno
== EAGAIN
))
1903 return buffer_len(&c
->input
);
1905 debug2("channel %d: ctl read<=0 rfd %d len %d",
1906 c
->self
, c
->rfd
, len
);
1907 chan_read_failed(c
);
1910 buffer_append(&c
->input
, buf
, len
);
1912 return buffer_len(&c
->input
);
1916 channel_post_mux_client(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1922 fatal("%s: entered with !compat20", __func__
);
1924 if (c
->rfd
!= -1 && !c
->mux_pause
&& FD_ISSET(c
->rfd
, readset
) &&
1925 (c
->istate
== CHAN_INPUT_OPEN
||
1926 c
->istate
== CHAN_INPUT_WAIT_DRAIN
)) {
1928 * Don't not read past the precise end of packets to
1929 * avoid disrupting fd passing.
1931 if (read_mux(c
, 4) < 4) /* read header */
1933 need
= get_u32(buffer_ptr(&c
->input
));
1934 #define CHANNEL_MUX_MAX_PACKET (256 * 1024)
1935 if (need
> CHANNEL_MUX_MAX_PACKET
) {
1936 debug2("channel %d: packet too big %u > %u",
1937 c
->self
, CHANNEL_MUX_MAX_PACKET
, need
);
1938 chan_rcvd_oclose(c
);
1941 if (read_mux(c
, need
+ 4) < need
+ 4) /* read body */
1943 if (c
->mux_rcb(c
) != 0) {
1944 debug("channel %d: mux_rcb failed", c
->self
);
1950 if (c
->wfd
!= -1 && FD_ISSET(c
->wfd
, writeset
) &&
1951 buffer_len(&c
->output
) > 0) {
1952 len
= write(c
->wfd
, buffer_ptr(&c
->output
),
1953 buffer_len(&c
->output
));
1954 if (len
< 0 && (errno
== EINTR
|| errno
== EAGAIN
))
1960 buffer_consume(&c
->output
, len
);
1965 channel_post_mux_listener(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
1968 struct sockaddr_storage addr
;
1974 if (!FD_ISSET(c
->sock
, readset
))
1977 debug("multiplexing control connection");
1980 * Accept connection on control socket
1982 memset(&addr
, 0, sizeof(addr
));
1983 addrlen
= sizeof(addr
);
1984 if ((newsock
= accept(c
->sock
, (struct sockaddr
*)&addr
,
1986 error("%s accept: %s", __func__
, strerror(errno
));
1987 if (errno
== EMFILE
|| errno
== ENFILE
)
1988 c
->notbefore
= monotime() + 1;
1992 if (getpeereid(newsock
, &euid
, &egid
) < 0) {
1993 error("%s getpeereid failed: %s", __func__
,
1998 if ((euid
!= 0) && (getuid() != euid
)) {
1999 error("multiplex uid mismatch: peer euid %u != uid %u",
2000 (u_int
)euid
, (u_int
)getuid());
2004 nc
= channel_new("multiplex client", SSH_CHANNEL_MUX_CLIENT
,
2005 newsock
, newsock
, -1, c
->local_window_max
,
2006 c
->local_maxpacket
, 0, "mux-control", 1);
2007 nc
->mux_rcb
= c
->mux_rcb
;
2008 debug3("%s: new mux channel %d fd %d", __func__
,
2009 nc
->self
, nc
->sock
);
2010 /* establish state */
2012 /* mux state transitions must not elicit protocol messages */
2013 nc
->flags
|= CHAN_LOCAL
;
2018 channel_post_output_drain_13(Channel
*c
, fd_set
*readset
, fd_set
*writeset
)
2022 /* Send buffered output data to the socket. */
2023 if (FD_ISSET(c
->sock
, writeset
) && buffer_len(&c
->output
) > 0) {
2024 len
= write(c
->sock
, buffer_ptr(&c
->output
),
2025 buffer_len(&c
->output
));
2027 buffer_clear(&c
->output
);
2029 buffer_consume(&c
->output
, len
);
2034 channel_handler_init_20(void)
2036 channel_pre
[SSH_CHANNEL_OPEN
] = &channel_pre_open
;
2037 channel_pre
[SSH_CHANNEL_X11_OPEN
] = &channel_pre_x11_open
;
2038 channel_pre
[SSH_CHANNEL_PORT_LISTENER
] = &channel_pre_listener
;
2039 channel_pre
[SSH_CHANNEL_RPORT_LISTENER
] = &channel_pre_listener
;
2040 channel_pre
[SSH_CHANNEL_UNIX_LISTENER
] = &channel_pre_listener
;
2041 channel_pre
[SSH_CHANNEL_RUNIX_LISTENER
] = &channel_pre_listener
;
2042 channel_pre
[SSH_CHANNEL_X11_LISTENER
] = &channel_pre_listener
;
2043 channel_pre
[SSH_CHANNEL_AUTH_SOCKET
] = &channel_pre_listener
;
2044 channel_pre
[SSH_CHANNEL_CONNECTING
] = &channel_pre_connecting
;
2045 channel_pre
[SSH_CHANNEL_DYNAMIC
] = &channel_pre_dynamic
;
2046 channel_pre
[SSH_CHANNEL_MUX_LISTENER
] = &channel_pre_listener
;
2047 channel_pre
[SSH_CHANNEL_MUX_CLIENT
] = &channel_pre_mux_client
;
2049 channel_post
[SSH_CHANNEL_OPEN
] = &channel_post_open
;
2050 channel_post
[SSH_CHANNEL_PORT_LISTENER
] = &channel_post_port_listener
;
2051 channel_post
[SSH_CHANNEL_RPORT_LISTENER
] = &channel_post_port_listener
;
2052 channel_post
[SSH_CHANNEL_UNIX_LISTENER
] = &channel_post_port_listener
;
2053 channel_post
[SSH_CHANNEL_RUNIX_LISTENER
] = &channel_post_port_listener
;
2054 channel_post
[SSH_CHANNEL_X11_LISTENER
] = &channel_post_x11_listener
;
2055 channel_post
[SSH_CHANNEL_AUTH_SOCKET
] = &channel_post_auth_listener
;
2056 channel_post
[SSH_CHANNEL_CONNECTING
] = &channel_post_connecting
;
2057 channel_post
[SSH_CHANNEL_DYNAMIC
] = &channel_post_open
;
2058 channel_post
[SSH_CHANNEL_MUX_LISTENER
] = &channel_post_mux_listener
;
2059 channel_post
[SSH_CHANNEL_MUX_CLIENT
] = &channel_post_mux_client
;
2063 channel_handler_init_13(void)
2065 channel_pre
[SSH_CHANNEL_OPEN
] = &channel_pre_open_13
;
2066 channel_pre
[SSH_CHANNEL_X11_OPEN
] = &channel_pre_x11_open_13
;
2067 channel_pre
[SSH_CHANNEL_X11_LISTENER
] = &channel_pre_listener
;
2068 channel_pre
[SSH_CHANNEL_PORT_LISTENER
] = &channel_pre_listener
;
2069 channel_pre
[SSH_CHANNEL_AUTH_SOCKET
] = &channel_pre_listener
;
2070 channel_pre
[SSH_CHANNEL_INPUT_DRAINING
] = &channel_pre_input_draining
;
2071 channel_pre
[SSH_CHANNEL_OUTPUT_DRAINING
] = &channel_pre_output_draining
;
2072 channel_pre
[SSH_CHANNEL_CONNECTING
] = &channel_pre_connecting
;
2073 channel_pre
[SSH_CHANNEL_DYNAMIC
] = &channel_pre_dynamic
;
2075 channel_post
[SSH_CHANNEL_OPEN
] = &channel_post_open
;
2076 channel_post
[SSH_CHANNEL_X11_LISTENER
] = &channel_post_x11_listener
;
2077 channel_post
[SSH_CHANNEL_PORT_LISTENER
] = &channel_post_port_listener
;
2078 channel_post
[SSH_CHANNEL_AUTH_SOCKET
] = &channel_post_auth_listener
;
2079 channel_post
[SSH_CHANNEL_OUTPUT_DRAINING
] = &channel_post_output_drain_13
;
2080 channel_post
[SSH_CHANNEL_CONNECTING
] = &channel_post_connecting
;
2081 channel_post
[SSH_CHANNEL_DYNAMIC
] = &channel_post_open
;
2085 channel_handler_init_15(void)
2087 channel_pre
[SSH_CHANNEL_OPEN
] = &channel_pre_open
;
2088 channel_pre
[SSH_CHANNEL_X11_OPEN
] = &channel_pre_x11_open
;
2089 channel_pre
[SSH_CHANNEL_X11_LISTENER
] = &channel_pre_listener
;
2090 channel_pre
[SSH_CHANNEL_PORT_LISTENER
] = &channel_pre_listener
;
2091 channel_pre
[SSH_CHANNEL_AUTH_SOCKET
] = &channel_pre_listener
;
2092 channel_pre
[SSH_CHANNEL_CONNECTING
] = &channel_pre_connecting
;
2093 channel_pre
[SSH_CHANNEL_DYNAMIC
] = &channel_pre_dynamic
;
2095 channel_post
[SSH_CHANNEL_X11_LISTENER
] = &channel_post_x11_listener
;
2096 channel_post
[SSH_CHANNEL_PORT_LISTENER
] = &channel_post_port_listener
;
2097 channel_post
[SSH_CHANNEL_AUTH_SOCKET
] = &channel_post_auth_listener
;
2098 channel_post
[SSH_CHANNEL_OPEN
] = &channel_post_open
;
2099 channel_post
[SSH_CHANNEL_CONNECTING
] = &channel_post_connecting
;
2100 channel_post
[SSH_CHANNEL_DYNAMIC
] = &channel_post_open
;
2104 channel_handler_init(void)
2108 for (i
= 0; i
< SSH_CHANNEL_MAX_TYPE
; i
++) {
2109 channel_pre
[i
] = NULL
;
2110 channel_post
[i
] = NULL
;
2113 channel_handler_init_20();
2115 channel_handler_init_13();
2117 channel_handler_init_15();
2120 /* gc dead channels */
2122 channel_garbage_collect(Channel
*c
)
2126 if (c
->detach_user
!= NULL
) {
2127 if (!chan_is_dead(c
, c
->detach_close
))
2129 debug2("channel %d: gc: notify user", c
->self
);
2130 c
->detach_user(c
->self
, NULL
);
2131 /* if we still have a callback */
2132 if (c
->detach_user
!= NULL
)
2134 debug2("channel %d: gc: user detached", c
->self
);
2136 if (!chan_is_dead(c
, 1))
2138 debug2("channel %d: garbage collecting", c
->self
);
2143 channel_handler(chan_fn
*ftab
[], fd_set
*readset
, fd_set
*writeset
,
2144 time_t *unpause_secs
)
2146 static int did_init
= 0;
2152 channel_handler_init();
2156 if (unpause_secs
!= NULL
)
2158 for (i
= 0, oalloc
= channels_alloc
; i
< oalloc
; i
++) {
2163 if (ftab
== channel_pre
)
2168 if (ftab
[c
->type
] != NULL
) {
2170 * Run handlers that are not paused.
2172 if (c
->notbefore
<= now
)
2173 (*ftab
[c
->type
])(c
, readset
, writeset
);
2174 else if (unpause_secs
!= NULL
) {
2176 * Collect the time that the earliest
2177 * channel comes off pause.
2179 debug3("%s: chan %d: skip for %d more seconds",
2181 (int)(c
->notbefore
- now
));
2182 if (*unpause_secs
== 0 ||
2183 (c
->notbefore
- now
) < *unpause_secs
)
2184 *unpause_secs
= c
->notbefore
- now
;
2187 channel_garbage_collect(c
);
2189 if (unpause_secs
!= NULL
&& *unpause_secs
!= 0)
2190 debug3("%s: first channel unpauses in %d seconds",
2191 __func__
, (int)*unpause_secs
);
2195 * Allocate/update select bitmasks and add any bits relevant to channels in
2199 channel_prepare_select(fd_set
**readsetp
, fd_set
**writesetp
, int *maxfdp
,
2200 u_int
*nallocp
, time_t *minwait_secs
, int rekeying
)
2202 u_int n
, sz
, nfdset
;
2204 n
= MAX(*maxfdp
, channel_max_fd
);
2206 nfdset
= howmany(n
+1, NFDBITS
);
2207 /* Explicitly test here, because xrealloc isn't always called */
2208 if (nfdset
&& SIZE_MAX
/ nfdset
< sizeof(fd_mask
))
2209 fatal("channel_prepare_select: max_fd (%d) is too large", n
);
2210 sz
= nfdset
* sizeof(fd_mask
);
2212 /* perhaps check sz < nalloc/2 and shrink? */
2213 if (*readsetp
== NULL
|| sz
> *nallocp
) {
2214 *readsetp
= xreallocarray(*readsetp
, nfdset
, sizeof(fd_mask
));
2215 *writesetp
= xreallocarray(*writesetp
, nfdset
, sizeof(fd_mask
));
2219 memset(*readsetp
, 0, sz
);
2220 memset(*writesetp
, 0, sz
);
2223 channel_handler(channel_pre
, *readsetp
, *writesetp
,
2228 * After select, perform any appropriate operations for channels which have
2232 channel_after_select(fd_set
*readset
, fd_set
*writeset
)
2234 channel_handler(channel_post
, readset
, writeset
, NULL
);
2238 /* If there is data to send to the connection, enqueue some of it now. */
2240 channel_output_poll(void)
2245 for (i
= 0; i
< channels_alloc
; i
++) {
2251 * We are only interested in channels that can have buffered
2255 if (c
->type
!= SSH_CHANNEL_OPEN
&&
2256 c
->type
!= SSH_CHANNEL_INPUT_DRAINING
)
2259 if (c
->type
!= SSH_CHANNEL_OPEN
)
2263 (c
->flags
& (CHAN_CLOSE_SENT
|CHAN_CLOSE_RCVD
))) {
2264 /* XXX is this true? */
2265 debug3("channel %d: will not send data after close", c
->self
);
2269 /* Get the amount of buffered data for this channel. */
2270 if ((c
->istate
== CHAN_INPUT_OPEN
||
2271 c
->istate
== CHAN_INPUT_WAIT_DRAIN
) &&
2272 (len
= buffer_len(&c
->input
)) > 0) {
2278 data
= buffer_get_string(&c
->input
,
2280 if (dlen
> c
->remote_window
||
2281 dlen
> c
->remote_maxpacket
) {
2282 debug("channel %d: datagram "
2283 "too big for channel",
2288 packet_start(SSH2_MSG_CHANNEL_DATA
);
2289 packet_put_int(c
->remote_id
);
2290 packet_put_string(data
, dlen
);
2292 c
->remote_window
-= dlen
;
2298 * Send some data for the other side over the secure
2302 if (len
> c
->remote_window
)
2303 len
= c
->remote_window
;
2304 if (len
> c
->remote_maxpacket
)
2305 len
= c
->remote_maxpacket
;
2307 if (packet_is_interactive()) {
2311 /* Keep the packets at reasonable size. */
2312 if (len
> packet_get_maxsize()/2)
2313 len
= packet_get_maxsize()/2;
2317 packet_start(compat20
?
2318 SSH2_MSG_CHANNEL_DATA
: SSH_MSG_CHANNEL_DATA
);
2319 packet_put_int(c
->remote_id
);
2320 packet_put_string(buffer_ptr(&c
->input
), len
);
2322 buffer_consume(&c
->input
, len
);
2323 c
->remote_window
-= len
;
2325 } else if (c
->istate
== CHAN_INPUT_WAIT_DRAIN
) {
2327 fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
2329 * input-buffer is empty and read-socket shutdown:
2330 * tell peer, that we will not send more data: send IEOF.
2331 * hack for extended data: delay EOF if EFD still in use.
2333 if (CHANNEL_EFD_INPUT_ACTIVE(c
))
2334 debug2("channel %d: ibuf_empty delayed efd %d/(%d)",
2335 c
->self
, c
->efd
, buffer_len(&c
->extended
));
2339 /* Send extended data, i.e. stderr */
2341 !(c
->flags
& CHAN_EOF_SENT
) &&
2342 c
->remote_window
> 0 &&
2343 (len
= buffer_len(&c
->extended
)) > 0 &&
2344 c
->extended_usage
== CHAN_EXTENDED_READ
) {
2345 debug2("channel %d: rwin %u elen %u euse %d",
2346 c
->self
, c
->remote_window
, buffer_len(&c
->extended
),
2348 if (len
> c
->remote_window
)
2349 len
= c
->remote_window
;
2350 if (len
> c
->remote_maxpacket
)
2351 len
= c
->remote_maxpacket
;
2352 packet_start(SSH2_MSG_CHANNEL_EXTENDED_DATA
);
2353 packet_put_int(c
->remote_id
);
2354 packet_put_int(SSH2_EXTENDED_DATA_STDERR
);
2355 packet_put_string(buffer_ptr(&c
->extended
), len
);
2357 buffer_consume(&c
->extended
, len
);
2358 c
->remote_window
-= len
;
2359 debug2("channel %d: sent ext data %d", c
->self
, len
);
2365 /* -- protocol input */
2369 channel_input_data(int type
, u_int32_t seq
, void *ctxt
)
2373 u_int data_len
, win_len
;
2376 /* Get the channel number and verify it. */
2377 id
= packet_get_int();
2378 c
= channel_lookup(id
);
2380 packet_disconnect("Received data for nonexistent channel %d.", id
);
2382 /* Ignore any data for non-open channels (might happen on close) */
2383 if (c
->type
!= SSH_CHANNEL_OPEN
&&
2384 c
->type
!= SSH_CHANNEL_X11_OPEN
)
2388 data
= packet_get_string_ptr(&data_len
);
2391 win_len
+= 4; /* string length header */
2394 * Ignore data for protocol > 1.3 if output end is no longer open.
2395 * For protocol 2 the sending side is reducing its window as it sends
2396 * data, so we must 'fake' consumption of the data in order to ensure
2397 * that window updates are sent back. Otherwise the connection might
2400 if (!compat13
&& c
->ostate
!= CHAN_OUTPUT_OPEN
) {
2402 c
->local_window
-= win_len
;
2403 c
->local_consumed
+= win_len
;
2409 if (win_len
> c
->local_maxpacket
) {
2410 logit("channel %d: rcvd big packet %d, maxpack %d",
2411 c
->self
, win_len
, c
->local_maxpacket
);
2413 if (win_len
> c
->local_window
) {
2414 logit("channel %d: rcvd too much data %d, win %d",
2415 c
->self
, win_len
, c
->local_window
);
2418 c
->local_window
-= win_len
;
2421 buffer_put_string(&c
->output
, data
, data_len
);
2423 buffer_append(&c
->output
, data
, data_len
);
2430 channel_input_extended_data(int type
, u_int32_t seq
, void *ctxt
)
2434 u_int data_len
, tcode
;
2437 /* Get the channel number and verify it. */
2438 id
= packet_get_int();
2439 c
= channel_lookup(id
);
2442 packet_disconnect("Received extended_data for bad channel %d.", id
);
2443 if (c
->type
!= SSH_CHANNEL_OPEN
) {
2444 logit("channel %d: ext data for non open", id
);
2447 if (c
->flags
& CHAN_EOF_RCVD
) {
2448 if (datafellows
& SSH_BUG_EXTEOF
)
2449 debug("channel %d: accepting ext data after eof", id
);
2451 packet_disconnect("Received extended_data after EOF "
2452 "on channel %d.", id
);
2454 tcode
= packet_get_int();
2456 c
->extended_usage
!= CHAN_EXTENDED_WRITE
||
2457 tcode
!= SSH2_EXTENDED_DATA_STDERR
) {
2458 logit("channel %d: bad ext data", c
->self
);
2461 data
= packet_get_string(&data_len
);
2463 if (data_len
> c
->local_window
) {
2464 logit("channel %d: rcvd too much extended_data %d, win %d",
2465 c
->self
, data_len
, c
->local_window
);
2469 debug2("channel %d: rcvd ext data %d", c
->self
, data_len
);
2470 c
->local_window
-= data_len
;
2471 buffer_append(&c
->extended
, data
, data_len
);
2478 channel_input_ieof(int type
, u_int32_t seq
, void *ctxt
)
2483 id
= packet_get_int();
2485 c
= channel_lookup(id
);
2487 packet_disconnect("Received ieof for nonexistent channel %d.", id
);
2490 /* XXX force input close */
2491 if (c
->force_drain
&& c
->istate
== CHAN_INPUT_OPEN
) {
2492 debug("channel %d: FORCE input drain", c
->self
);
2493 c
->istate
= CHAN_INPUT_WAIT_DRAIN
;
2494 if (buffer_len(&c
->input
) == 0)
2502 channel_input_close(int type
, u_int32_t seq
, void *ctxt
)
2507 id
= packet_get_int();
2509 c
= channel_lookup(id
);
2511 packet_disconnect("Received close for nonexistent channel %d.", id
);
2514 * Send a confirmation that we have closed the channel and no more
2515 * data is coming for it.
2517 packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION
);
2518 packet_put_int(c
->remote_id
);
2522 * If the channel is in closed state, we have sent a close request,
2523 * and the other side will eventually respond with a confirmation.
2524 * Thus, we cannot free the channel here, because then there would be
2525 * no-one to receive the confirmation. The channel gets freed when
2526 * the confirmation arrives.
2528 if (c
->type
!= SSH_CHANNEL_CLOSED
) {
2530 * Not a closed channel - mark it as draining, which will
2531 * cause it to be freed later.
2533 buffer_clear(&c
->input
);
2534 c
->type
= SSH_CHANNEL_OUTPUT_DRAINING
;
2539 /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
2542 channel_input_oclose(int type
, u_int32_t seq
, void *ctxt
)
2544 int id
= packet_get_int();
2545 Channel
*c
= channel_lookup(id
);
2549 packet_disconnect("Received oclose for nonexistent channel %d.", id
);
2550 chan_rcvd_oclose(c
);
2556 channel_input_close_confirmation(int type
, u_int32_t seq
, void *ctxt
)
2558 int id
= packet_get_int();
2559 Channel
*c
= channel_lookup(id
);
2563 packet_disconnect("Received close confirmation for "
2564 "out-of-range channel %d.", id
);
2565 if (c
->type
!= SSH_CHANNEL_CLOSED
&& c
->type
!= SSH_CHANNEL_ABANDONED
)
2566 packet_disconnect("Received close confirmation for "
2567 "non-closed channel %d (type %d).", id
, c
->type
);
2574 channel_input_open_confirmation(int type
, u_int32_t seq
, void *ctxt
)
2579 id
= packet_get_int();
2580 c
= channel_lookup(id
);
2582 if (c
==NULL
|| c
->type
!= SSH_CHANNEL_OPENING
)
2583 packet_disconnect("Received open confirmation for "
2584 "non-opening channel %d.", id
);
2585 remote_id
= packet_get_int();
2586 /* Record the remote channel number and mark that the channel is now open. */
2587 c
->remote_id
= remote_id
;
2588 c
->type
= SSH_CHANNEL_OPEN
;
2591 c
->remote_window
= packet_get_int();
2592 c
->remote_maxpacket
= packet_get_int();
2593 if (c
->open_confirm
) {
2594 debug2("callback start");
2595 c
->open_confirm(c
->self
, 1, c
->open_confirm_ctx
);
2596 debug2("callback done");
2598 debug2("channel %d: open confirm rwindow %u rmax %u", c
->self
,
2599 c
->remote_window
, c
->remote_maxpacket
);
2606 reason2txt(int reason
)
2609 case SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED
:
2610 return "administratively prohibited";
2611 case SSH2_OPEN_CONNECT_FAILED
:
2612 return "connect failed";
2613 case SSH2_OPEN_UNKNOWN_CHANNEL_TYPE
:
2614 return "unknown channel type";
2615 case SSH2_OPEN_RESOURCE_SHORTAGE
:
2616 return "resource shortage";
2618 return "unknown reason";
2623 channel_input_open_failure(int type
, u_int32_t seq
, void *ctxt
)
2626 char *msg
= NULL
, *lang
= NULL
;
2629 id
= packet_get_int();
2630 c
= channel_lookup(id
);
2632 if (c
==NULL
|| c
->type
!= SSH_CHANNEL_OPENING
)
2633 packet_disconnect("Received open failure for "
2634 "non-opening channel %d.", id
);
2636 reason
= packet_get_int();
2637 if (!(datafellows
& SSH_BUG_OPENFAILURE
)) {
2638 msg
= packet_get_string(NULL
);
2639 lang
= packet_get_string(NULL
);
2641 logit("channel %d: open failed: %s%s%s", id
,
2642 reason2txt(reason
), msg
? ": ": "", msg
? msg
: "");
2645 if (c
->open_confirm
) {
2646 debug2("callback start");
2647 c
->open_confirm(c
->self
, 0, c
->open_confirm_ctx
);
2648 debug2("callback done");
2652 /* Schedule the channel for cleanup/deletion. */
2659 channel_input_window_adjust(int type
, u_int32_t seq
, void *ctxt
)
2668 /* Get the channel number and verify it. */
2669 id
= packet_get_int();
2670 c
= channel_lookup(id
);
2673 logit("Received window adjust for non-open channel %d.", id
);
2676 adjust
= packet_get_int();
2678 debug2("channel %d: rcvd adjust %u", id
, adjust
);
2679 if ((tmp
= c
->remote_window
+ adjust
) < c
->remote_window
)
2680 fatal("channel %d: adjust %u overflows remote window %u",
2681 id
, adjust
, c
->remote_window
);
2682 c
->remote_window
= tmp
;
2688 channel_input_port_open(int type
, u_int32_t seq
, void *ctxt
)
2692 char *host
, *originator_string
;
2695 remote_id
= packet_get_int();
2696 host
= packet_get_string(NULL
);
2697 host_port
= packet_get_int();
2699 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN
) {
2700 originator_string
= packet_get_string(NULL
);
2702 originator_string
= xstrdup("unknown (remote did not supply name)");
2705 c
= channel_connect_to_port(host
, host_port
,
2706 "connected socket", originator_string
);
2707 free(originator_string
);
2710 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE
);
2711 packet_put_int(remote_id
);
2714 c
->remote_id
= remote_id
;
2720 channel_input_status_confirm(int type
, u_int32_t seq
, void *ctxt
)
2723 struct channel_confirm
*cc
;
2726 /* Reset keepalive timeout */
2727 packet_set_alive_timeouts(0);
2729 id
= packet_get_int();
2732 debug2("channel_input_status_confirm: type %d id %d", type
, id
);
2734 if ((c
= channel_lookup(id
)) == NULL
) {
2735 logit("channel_input_status_confirm: %d: unknown", id
);
2738 if ((cc
= TAILQ_FIRST(&c
->status_confirms
)) == NULL
)
2740 cc
->cb(type
, c
, cc
->ctx
);
2741 TAILQ_REMOVE(&c
->status_confirms
, cc
, entry
);
2742 explicit_bzero(cc
, sizeof(*cc
));
2747 /* -- tcp forwarding */
2750 channel_set_af(int af
)
2757 * Determine whether or not a port forward listens to loopback, the
2758 * specified address or wildcard. On the client, a specified bind
2759 * address will always override gateway_ports. On the server, a
2760 * gateway_ports of 1 (``yes'') will override the client's specification
2761 * and force a wildcard bind, whereas a value of 2 (``clientspecified'')
2762 * will bind to whatever address the client asked for.
2764 * Special-case listen_addrs are:
2766 * "0.0.0.0" -> wildcard v4/v6 if SSH_OLD_FORWARD_ADDR
2767 * "" (empty string), "*" -> wildcard v4/v6
2768 * "localhost" -> loopback v4/v6
2769 * "127.0.0.1" / "::1" -> accepted even if gateway_ports isn't set
2772 channel_fwd_bind_addr(const char *listen_addr
, int *wildcardp
,
2773 int is_client
, struct ForwardOptions
*fwd_opts
)
2775 const char *addr
= NULL
;
2778 if (listen_addr
== NULL
) {
2779 /* No address specified: default to gateway_ports setting */
2780 if (fwd_opts
->gateway_ports
)
2782 } else if (fwd_opts
->gateway_ports
|| is_client
) {
2783 if (((datafellows
& SSH_OLD_FORWARD_ADDR
) &&
2784 strcmp(listen_addr
, "0.0.0.0") == 0 && is_client
== 0) ||
2785 *listen_addr
== '\0' || strcmp(listen_addr
, "*") == 0 ||
2786 (!is_client
&& fwd_opts
->gateway_ports
== 1)) {
2789 * Notify client if they requested a specific listen
2790 * address and it was overridden.
2792 if (*listen_addr
!= '\0' &&
2793 strcmp(listen_addr
, "0.0.0.0") != 0 &&
2794 strcmp(listen_addr
, "*") != 0) {
2795 packet_send_debug("Forwarding listen address "
2796 "\"%s\" overridden by server "
2797 "GatewayPorts", listen_addr
);
2799 } else if (strcmp(listen_addr
, "localhost") != 0 ||
2800 strcmp(listen_addr
, "127.0.0.1") == 0 ||
2801 strcmp(listen_addr
, "::1") == 0) {
2802 /* Accept localhost address when GatewayPorts=yes */
2805 } else if (strcmp(listen_addr
, "127.0.0.1") == 0 ||
2806 strcmp(listen_addr
, "::1") == 0) {
2808 * If a specific IPv4/IPv6 localhost address has been
2809 * requested then accept it even if gateway_ports is in
2810 * effect. This allows the client to prefer IPv4 or IPv6.
2814 if (wildcardp
!= NULL
)
2815 *wildcardp
= wildcard
;
2820 channel_setup_fwd_listener_tcpip(int type
, struct Forward
*fwd
,
2821 int *allocated_listen_port
, struct ForwardOptions
*fwd_opts
)
2824 int sock
, r
, success
= 0, wildcard
= 0, is_client
;
2825 struct addrinfo hints
, *ai
, *aitop
;
2826 const char *host
, *addr
;
2827 char ntop
[NI_MAXHOST
], strport
[NI_MAXSERV
];
2830 is_client
= (type
== SSH_CHANNEL_PORT_LISTENER
);
2832 if (is_client
&& fwd
->connect_path
!= NULL
) {
2833 host
= fwd
->connect_path
;
2835 host
= (type
== SSH_CHANNEL_RPORT_LISTENER
) ?
2836 fwd
->listen_host
: fwd
->connect_host
;
2838 error("No forward host name.");
2841 if (strlen(host
) >= NI_MAXHOST
) {
2842 error("Forward host name too long.");
2847 /* Determine the bind address, cf. channel_fwd_bind_addr() comment */
2848 addr
= channel_fwd_bind_addr(fwd
->listen_host
, &wildcard
,
2849 is_client
, fwd_opts
);
2850 debug3("%s: type %d wildcard %d addr %s", __func__
,
2851 type
, wildcard
, (addr
== NULL
) ? "NULL" : addr
);
2854 * getaddrinfo returns a loopback address if the hostname is
2855 * set to NULL and hints.ai_flags is not AI_PASSIVE
2857 memset(&hints
, 0, sizeof(hints
));
2858 hints
.ai_family
= IPv4or6
;
2859 hints
.ai_flags
= wildcard
? AI_PASSIVE
: 0;
2860 hints
.ai_socktype
= SOCK_STREAM
;
2861 snprintf(strport
, sizeof strport
, "%d", fwd
->listen_port
);
2862 if ((r
= getaddrinfo(addr
, strport
, &hints
, &aitop
)) != 0) {
2864 /* This really shouldn't happen */
2865 packet_disconnect("getaddrinfo: fatal error: %s",
2866 ssh_gai_strerror(r
));
2868 error("%s: getaddrinfo(%.64s): %s", __func__
, addr
,
2869 ssh_gai_strerror(r
));
2873 if (allocated_listen_port
!= NULL
)
2874 *allocated_listen_port
= 0;
2875 for (ai
= aitop
; ai
; ai
= ai
->ai_next
) {
2876 switch (ai
->ai_family
) {
2878 lport_p
= &((struct sockaddr_in
*)ai
->ai_addr
)->
2882 lport_p
= &((struct sockaddr_in6
*)ai
->ai_addr
)->
2889 * If allocating a port for -R forwards, then use the
2890 * same port for all address families.
2892 if (type
== SSH_CHANNEL_RPORT_LISTENER
&& fwd
->listen_port
== 0 &&
2893 allocated_listen_port
!= NULL
&& *allocated_listen_port
> 0)
2894 *lport_p
= htons(*allocated_listen_port
);
2896 if (getnameinfo(ai
->ai_addr
, ai
->ai_addrlen
, ntop
, sizeof(ntop
),
2897 strport
, sizeof(strport
), NI_NUMERICHOST
|NI_NUMERICSERV
) != 0) {
2898 error("%s: getnameinfo failed", __func__
);
2901 /* Create a port to listen for the host. */
2902 sock
= socket(ai
->ai_family
, ai
->ai_socktype
, ai
->ai_protocol
);
2904 /* this is no error since kernel may not support ipv6 */
2905 verbose("socket: %.100s", strerror(errno
));
2909 channel_set_reuseaddr(sock
);
2910 if (ai
->ai_family
== AF_INET6
)
2911 sock_set_v6only(sock
);
2913 debug("Local forwarding listening on %s port %s.",
2916 /* Bind the socket to the address. */
2917 if (bind(sock
, ai
->ai_addr
, ai
->ai_addrlen
) < 0) {
2918 /* address can be in use ipv6 address is already bound */
2920 error("bind: %.100s", strerror(errno
));
2922 verbose("bind: %.100s", strerror(errno
));
2927 /* Start listening for connections on the socket. */
2928 if (listen(sock
, SSH_LISTEN_BACKLOG
) < 0) {
2929 error("listen: %.100s", strerror(errno
));
2935 * fwd->listen_port == 0 requests a dynamically allocated port -
2936 * record what we got.
2938 if (type
== SSH_CHANNEL_RPORT_LISTENER
&& fwd
->listen_port
== 0 &&
2939 allocated_listen_port
!= NULL
&&
2940 *allocated_listen_port
== 0) {
2941 *allocated_listen_port
= get_local_port(sock
);
2942 debug("Allocated listen port %d",
2943 *allocated_listen_port
);
2946 /* Allocate a channel number for the socket. */
2947 c
= channel_new("port listener", type
, sock
, sock
, -1,
2948 CHAN_TCP_WINDOW_DEFAULT
, CHAN_TCP_PACKET_DEFAULT
,
2949 0, "port listener", 1);
2950 c
->path
= xstrdup(host
);
2951 c
->host_port
= fwd
->connect_port
;
2952 c
->listening_addr
= addr
== NULL
? NULL
: xstrdup(addr
);
2953 if (fwd
->listen_port
== 0 && allocated_listen_port
!= NULL
&&
2954 !(datafellows
& SSH_BUG_DYNAMIC_RPORT
))
2955 c
->listening_port
= *allocated_listen_port
;
2957 c
->listening_port
= fwd
->listen_port
;
2961 error("%s: cannot listen to port: %d", __func__
,
2963 freeaddrinfo(aitop
);
2968 channel_setup_fwd_listener_streamlocal(int type
, struct Forward
*fwd
,
2969 struct ForwardOptions
*fwd_opts
)
2971 struct sockaddr_un sunaddr
;
2978 case SSH_CHANNEL_UNIX_LISTENER
:
2979 if (fwd
->connect_path
!= NULL
) {
2980 if (strlen(fwd
->connect_path
) > sizeof(sunaddr
.sun_path
)) {
2981 error("Local connecting path too long: %s",
2985 path
= fwd
->connect_path
;
2986 port
= PORT_STREAMLOCAL
;
2988 if (fwd
->connect_host
== NULL
) {
2989 error("No forward host name.");
2992 if (strlen(fwd
->connect_host
) >= NI_MAXHOST
) {
2993 error("Forward host name too long.");
2996 path
= fwd
->connect_host
;
2997 port
= fwd
->connect_port
;
3000 case SSH_CHANNEL_RUNIX_LISTENER
:
3001 path
= fwd
->listen_path
;
3002 port
= PORT_STREAMLOCAL
;
3005 error("%s: unexpected channel type %d", __func__
, type
);
3009 if (fwd
->listen_path
== NULL
) {
3010 error("No forward path name.");
3013 if (strlen(fwd
->listen_path
) > sizeof(sunaddr
.sun_path
)) {
3014 error("Local listening path too long: %s", fwd
->listen_path
);
3018 debug3("%s: type %d path %s", __func__
, type
, fwd
->listen_path
);
3020 /* Start a Unix domain listener. */
3021 omask
= umask(fwd_opts
->streamlocal_bind_mask
);
3022 sock
= unix_listener(fwd
->listen_path
, SSH_LISTEN_BACKLOG
,
3023 fwd_opts
->streamlocal_bind_unlink
);
3028 debug("Local forwarding listening on path %s.", fwd
->listen_path
);
3030 /* Allocate a channel number for the socket. */
3031 c
= channel_new("unix listener", type
, sock
, sock
, -1,
3032 CHAN_TCP_WINDOW_DEFAULT
, CHAN_TCP_PACKET_DEFAULT
,
3033 0, "unix listener", 1);
3034 c
->path
= xstrdup(path
);
3035 c
->host_port
= port
;
3036 c
->listening_port
= PORT_STREAMLOCAL
;
3037 c
->listening_addr
= xstrdup(fwd
->listen_path
);
3042 channel_cancel_rport_listener_tcpip(const char *host
, u_short port
)
3047 for (i
= 0; i
< channels_alloc
; i
++) {
3048 Channel
*c
= channels
[i
];
3049 if (c
== NULL
|| c
->type
!= SSH_CHANNEL_RPORT_LISTENER
)
3051 if (strcmp(c
->path
, host
) == 0 && c
->listening_port
== port
) {
3052 debug2("%s: close channel %d", __func__
, i
);
3062 channel_cancel_rport_listener_streamlocal(const char *path
)
3067 for (i
= 0; i
< channels_alloc
; i
++) {
3068 Channel
*c
= channels
[i
];
3069 if (c
== NULL
|| c
->type
!= SSH_CHANNEL_RUNIX_LISTENER
)
3071 if (c
->path
== NULL
)
3073 if (strcmp(c
->path
, path
) == 0) {
3074 debug2("%s: close channel %d", __func__
, i
);
3084 channel_cancel_rport_listener(struct Forward
*fwd
)
3086 if (fwd
->listen_path
!= NULL
)
3087 return channel_cancel_rport_listener_streamlocal(fwd
->listen_path
);
3089 return channel_cancel_rport_listener_tcpip(fwd
->listen_host
, fwd
->listen_port
);
3093 channel_cancel_lport_listener_tcpip(const char *lhost
, u_short lport
,
3094 int cport
, struct ForwardOptions
*fwd_opts
)
3098 const char *addr
= channel_fwd_bind_addr(lhost
, NULL
, 1, fwd_opts
);
3100 for (i
= 0; i
< channels_alloc
; i
++) {
3101 Channel
*c
= channels
[i
];
3102 if (c
== NULL
|| c
->type
!= SSH_CHANNEL_PORT_LISTENER
)
3104 if (c
->listening_port
!= lport
)
3106 if (cport
== CHANNEL_CANCEL_PORT_STATIC
) {
3107 /* skip dynamic forwardings */
3108 if (c
->host_port
== 0)
3111 if (c
->host_port
!= cport
)
3114 if ((c
->listening_addr
== NULL
&& addr
!= NULL
) ||
3115 (c
->listening_addr
!= NULL
&& addr
== NULL
))
3117 if (addr
== NULL
|| strcmp(c
->listening_addr
, addr
) == 0) {
3118 debug2("%s: close channel %d", __func__
, i
);
3128 channel_cancel_lport_listener_streamlocal(const char *path
)
3134 error("%s: no path specified.", __func__
);
3138 for (i
= 0; i
< channels_alloc
; i
++) {
3139 Channel
*c
= channels
[i
];
3140 if (c
== NULL
|| c
->type
!= SSH_CHANNEL_UNIX_LISTENER
)
3142 if (c
->listening_addr
== NULL
)
3144 if (strcmp(c
->listening_addr
, path
) == 0) {
3145 debug2("%s: close channel %d", __func__
, i
);
3155 channel_cancel_lport_listener(struct Forward
*fwd
, int cport
, struct ForwardOptions
*fwd_opts
)
3157 if (fwd
->listen_path
!= NULL
)
3158 return channel_cancel_lport_listener_streamlocal(fwd
->listen_path
);
3160 return channel_cancel_lport_listener_tcpip(fwd
->listen_host
, fwd
->listen_port
, cport
, fwd_opts
);
3163 /* protocol local port fwd, used by ssh (and sshd in v1) */
3165 channel_setup_local_fwd_listener(struct Forward
*fwd
, struct ForwardOptions
*fwd_opts
)
3167 if (fwd
->listen_path
!= NULL
) {
3168 return channel_setup_fwd_listener_streamlocal(
3169 SSH_CHANNEL_UNIX_LISTENER
, fwd
, fwd_opts
);
3171 return channel_setup_fwd_listener_tcpip(SSH_CHANNEL_PORT_LISTENER
,
3172 fwd
, NULL
, fwd_opts
);
3176 /* protocol v2 remote port fwd, used by sshd */
3178 channel_setup_remote_fwd_listener(struct Forward
*fwd
,
3179 int *allocated_listen_port
, struct ForwardOptions
*fwd_opts
)
3181 if (fwd
->listen_path
!= NULL
) {
3182 return channel_setup_fwd_listener_streamlocal(
3183 SSH_CHANNEL_RUNIX_LISTENER
, fwd
, fwd_opts
);
3185 return channel_setup_fwd_listener_tcpip(
3186 SSH_CHANNEL_RPORT_LISTENER
, fwd
, allocated_listen_port
,
3192 * Translate the requested rfwd listen host to something usable for
3196 channel_rfwd_bind_host(const char *listen_host
)
3198 if (listen_host
== NULL
) {
3199 if (datafellows
& SSH_BUG_RFWD_ADDR
)
3203 } else if (*listen_host
== '\0' || strcmp(listen_host
, "*") == 0) {
3204 if (datafellows
& SSH_BUG_RFWD_ADDR
)
3213 * Initiate forwarding of connections to port "port" on remote host through
3214 * the secure channel to host:port from local side.
3215 * Returns handle (index) for updating the dynamic listen port with
3216 * channel_update_permitted_opens().
3219 channel_request_remote_forwarding(struct Forward
*fwd
)
3221 int type
, success
= 0, idx
= -1;
3223 /* Send the forward request to the remote side. */
3225 packet_start(SSH2_MSG_GLOBAL_REQUEST
);
3226 if (fwd
->listen_path
!= NULL
) {
3227 packet_put_cstring("streamlocal-forward@openssh.com");
3228 packet_put_char(1); /* boolean: want reply */
3229 packet_put_cstring(fwd
->listen_path
);
3231 packet_put_cstring("tcpip-forward");
3232 packet_put_char(1); /* boolean: want reply */
3233 packet_put_cstring(channel_rfwd_bind_host(fwd
->listen_host
));
3234 packet_put_int(fwd
->listen_port
);
3237 packet_write_wait();
3238 /* Assume that server accepts the request */
3240 } else if (fwd
->listen_path
== NULL
) {
3241 packet_start(SSH_CMSG_PORT_FORWARD_REQUEST
);
3242 packet_put_int(fwd
->listen_port
);
3243 packet_put_cstring(fwd
->connect_host
);
3244 packet_put_int(fwd
->connect_port
);
3246 packet_write_wait();
3248 /* Wait for response from the remote side. */
3249 type
= packet_read();
3251 case SSH_SMSG_SUCCESS
:
3254 case SSH_SMSG_FAILURE
:
3257 /* Unknown packet */
3258 packet_disconnect("Protocol error for port forward request:"
3259 "received packet type %d.", type
);
3262 logit("Warning: Server does not support remote stream local forwarding.");
3265 /* Record that connection to this host/port is permitted. */
3266 permitted_opens
= xreallocarray(permitted_opens
,
3267 num_permitted_opens
+ 1, sizeof(*permitted_opens
));
3268 idx
= num_permitted_opens
++;
3269 if (fwd
->connect_path
!= NULL
) {
3270 permitted_opens
[idx
].host_to_connect
=
3271 xstrdup(fwd
->connect_path
);
3272 permitted_opens
[idx
].port_to_connect
=
3275 permitted_opens
[idx
].host_to_connect
=
3276 xstrdup(fwd
->connect_host
);
3277 permitted_opens
[idx
].port_to_connect
=
3280 if (fwd
->listen_path
!= NULL
) {
3281 permitted_opens
[idx
].listen_host
= NULL
;
3282 permitted_opens
[idx
].listen_path
=
3283 xstrdup(fwd
->listen_path
);
3284 permitted_opens
[idx
].listen_port
= PORT_STREAMLOCAL
;
3286 permitted_opens
[idx
].listen_host
=
3287 fwd
->listen_host
? xstrdup(fwd
->listen_host
) : NULL
;
3288 permitted_opens
[idx
].listen_path
= NULL
;
3289 permitted_opens
[idx
].listen_port
= fwd
->listen_port
;
3296 open_match(ForwardPermission
*allowed_open
, const char *requestedhost
,
3299 if (allowed_open
->host_to_connect
== NULL
)
3301 if (allowed_open
->port_to_connect
!= FWD_PERMIT_ANY_PORT
&&
3302 allowed_open
->port_to_connect
!= requestedport
)
3304 if (strcmp(allowed_open
->host_to_connect
, FWD_PERMIT_ANY_HOST
) != 0 &&
3305 strcmp(allowed_open
->host_to_connect
, requestedhost
) != 0)
3311 * Note that in the listen host/port case
3312 * we don't support FWD_PERMIT_ANY_PORT and
3313 * need to translate between the configured-host (listen_host)
3314 * and what we've sent to the remote server (channel_rfwd_bind_host)
3317 open_listen_match_tcpip(ForwardPermission
*allowed_open
,
3318 const char *requestedhost
, u_short requestedport
, int translate
)
3320 const char *allowed_host
;
3322 if (allowed_open
->host_to_connect
== NULL
)
3324 if (allowed_open
->listen_port
!= requestedport
)
3326 if (!translate
&& allowed_open
->listen_host
== NULL
&&
3327 requestedhost
== NULL
)
3329 allowed_host
= translate
?
3330 channel_rfwd_bind_host(allowed_open
->listen_host
) :
3331 allowed_open
->listen_host
;
3332 if (allowed_host
== NULL
||
3333 strcmp(allowed_host
, requestedhost
) != 0)
3339 open_listen_match_streamlocal(ForwardPermission
*allowed_open
,
3340 const char *requestedpath
)
3342 if (allowed_open
->host_to_connect
== NULL
)
3344 if (allowed_open
->listen_port
!= PORT_STREAMLOCAL
)
3346 if (allowed_open
->listen_path
== NULL
||
3347 strcmp(allowed_open
->listen_path
, requestedpath
) != 0)
3353 * Request cancellation of remote forwarding of connection host:port from
3357 channel_request_rforward_cancel_tcpip(const char *host
, u_short port
)
3364 for (i
= 0; i
< num_permitted_opens
; i
++) {
3365 if (open_listen_match_tcpip(&permitted_opens
[i
], host
, port
, 0))
3368 if (i
>= num_permitted_opens
) {
3369 debug("%s: requested forward not found", __func__
);
3372 packet_start(SSH2_MSG_GLOBAL_REQUEST
);
3373 packet_put_cstring("cancel-tcpip-forward");
3375 packet_put_cstring(channel_rfwd_bind_host(host
));
3376 packet_put_int(port
);
3379 permitted_opens
[i
].listen_port
= 0;
3380 permitted_opens
[i
].port_to_connect
= 0;
3381 free(permitted_opens
[i
].host_to_connect
);
3382 permitted_opens
[i
].host_to_connect
= NULL
;
3383 free(permitted_opens
[i
].listen_host
);
3384 permitted_opens
[i
].listen_host
= NULL
;
3385 permitted_opens
[i
].listen_path
= NULL
;
3391 * Request cancellation of remote forwarding of Unix domain socket
3392 * path from local side.
3395 channel_request_rforward_cancel_streamlocal(const char *path
)
3402 for (i
= 0; i
< num_permitted_opens
; i
++) {
3403 if (open_listen_match_streamlocal(&permitted_opens
[i
], path
))
3406 if (i
>= num_permitted_opens
) {
3407 debug("%s: requested forward not found", __func__
);
3410 packet_start(SSH2_MSG_GLOBAL_REQUEST
);
3411 packet_put_cstring("cancel-streamlocal-forward@openssh.com");
3413 packet_put_cstring(path
);
3416 permitted_opens
[i
].listen_port
= 0;
3417 permitted_opens
[i
].port_to_connect
= 0;
3418 free(permitted_opens
[i
].host_to_connect
);
3419 permitted_opens
[i
].host_to_connect
= NULL
;
3420 permitted_opens
[i
].listen_host
= NULL
;
3421 free(permitted_opens
[i
].listen_path
);
3422 permitted_opens
[i
].listen_path
= NULL
;
3428 * Request cancellation of remote forwarding of a connection from local side.
3431 channel_request_rforward_cancel(struct Forward
*fwd
)
3433 if (fwd
->listen_path
!= NULL
) {
3434 return (channel_request_rforward_cancel_streamlocal(
3437 return (channel_request_rforward_cancel_tcpip(fwd
->listen_host
,
3438 fwd
->listen_port
? fwd
->listen_port
: fwd
->allocated_port
));
3443 * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
3444 * listening for the port, and sends back a success reply (or disconnect
3445 * message if there was an error).
3448 channel_input_port_forward_request(int is_root
, struct ForwardOptions
*fwd_opts
)
3453 /* Get arguments from the packet. */
3454 memset(&fwd
, 0, sizeof(fwd
));
3455 fwd
.listen_port
= packet_get_int();
3456 fwd
.connect_host
= packet_get_string(NULL
);
3457 fwd
.connect_port
= packet_get_int();
3461 * Check that an unprivileged user is not trying to forward a
3464 if (fwd
.listen_port
< IPPORT_RESERVED
&& !is_root
)
3466 "Requested forwarding of port %d but user is not root.",
3468 if (fwd
.connect_port
== 0)
3469 packet_disconnect("Dynamic forwarding denied.");
3472 /* Initiate forwarding */
3473 success
= channel_setup_local_fwd_listener(&fwd
, fwd_opts
);
3475 /* Free the argument string. */
3476 free(fwd
.connect_host
);
3478 return (success
? 0 : -1);
3482 * Permits opening to any host/port if permitted_opens[] is empty. This is
3483 * usually called by the server, because the user could connect to any port
3484 * anyway, and the server has no way to know but to trust the client anyway.
3487 channel_permit_all_opens(void)
3489 if (num_permitted_opens
== 0)
3490 all_opens_permitted
= 1;
3494 channel_add_permitted_opens(char *host
, int port
)
3496 debug("allow port forwarding to host %s port %d", host
, port
);
3498 permitted_opens
= xreallocarray(permitted_opens
,
3499 num_permitted_opens
+ 1, sizeof(*permitted_opens
));
3500 permitted_opens
[num_permitted_opens
].host_to_connect
= xstrdup(host
);
3501 permitted_opens
[num_permitted_opens
].port_to_connect
= port
;
3502 permitted_opens
[num_permitted_opens
].listen_host
= NULL
;
3503 permitted_opens
[num_permitted_opens
].listen_path
= NULL
;
3504 permitted_opens
[num_permitted_opens
].listen_port
= 0;
3505 num_permitted_opens
++;
3507 all_opens_permitted
= 0;
3511 * Update the listen port for a dynamic remote forward, after
3512 * the actual 'newport' has been allocated. If 'newport' < 0 is
3513 * passed then they entry will be invalidated.
3516 channel_update_permitted_opens(int idx
, int newport
)
3518 if (idx
< 0 || idx
>= num_permitted_opens
) {
3519 debug("channel_update_permitted_opens: index out of range:"
3520 " %d num_permitted_opens %d", idx
, num_permitted_opens
);
3523 debug("%s allowed port %d for forwarding to host %s port %d",
3524 newport
> 0 ? "Updating" : "Removing",
3526 permitted_opens
[idx
].host_to_connect
,
3527 permitted_opens
[idx
].port_to_connect
);
3529 permitted_opens
[idx
].listen_port
=
3530 (datafellows
& SSH_BUG_DYNAMIC_RPORT
) ? 0 : newport
;
3532 permitted_opens
[idx
].listen_port
= 0;
3533 permitted_opens
[idx
].port_to_connect
= 0;
3534 free(permitted_opens
[idx
].host_to_connect
);
3535 permitted_opens
[idx
].host_to_connect
= NULL
;
3536 free(permitted_opens
[idx
].listen_host
);
3537 permitted_opens
[idx
].listen_host
= NULL
;
3538 free(permitted_opens
[idx
].listen_path
);
3539 permitted_opens
[idx
].listen_path
= NULL
;
3544 channel_add_adm_permitted_opens(char *host
, int port
)
3546 debug("config allows port forwarding to host %s port %d", host
, port
);
3548 permitted_adm_opens
= xreallocarray(permitted_adm_opens
,
3549 num_adm_permitted_opens
+ 1, sizeof(*permitted_adm_opens
));
3550 permitted_adm_opens
[num_adm_permitted_opens
].host_to_connect
3552 permitted_adm_opens
[num_adm_permitted_opens
].port_to_connect
= port
;
3553 permitted_adm_opens
[num_adm_permitted_opens
].listen_host
= NULL
;
3554 permitted_adm_opens
[num_adm_permitted_opens
].listen_path
= NULL
;
3555 permitted_adm_opens
[num_adm_permitted_opens
].listen_port
= 0;
3556 return ++num_adm_permitted_opens
;
3560 channel_disable_adm_local_opens(void)
3562 channel_clear_adm_permitted_opens();
3563 permitted_adm_opens
= xcalloc(sizeof(*permitted_adm_opens
), 1);
3564 permitted_adm_opens
[num_adm_permitted_opens
].host_to_connect
= NULL
;
3565 num_adm_permitted_opens
= 1;
3569 channel_clear_permitted_opens(void)
3573 for (i
= 0; i
< num_permitted_opens
; i
++) {
3574 free(permitted_opens
[i
].host_to_connect
);
3575 free(permitted_opens
[i
].listen_host
);
3576 free(permitted_opens
[i
].listen_path
);
3578 free(permitted_opens
);
3579 permitted_opens
= NULL
;
3580 num_permitted_opens
= 0;
3584 channel_clear_adm_permitted_opens(void)
3588 for (i
= 0; i
< num_adm_permitted_opens
; i
++) {
3589 free(permitted_adm_opens
[i
].host_to_connect
);
3590 free(permitted_adm_opens
[i
].listen_host
);
3591 free(permitted_adm_opens
[i
].listen_path
);
3593 free(permitted_adm_opens
);
3594 permitted_adm_opens
= NULL
;
3595 num_adm_permitted_opens
= 0;
3599 channel_print_adm_permitted_opens(void)
3603 printf("permitopen");
3604 if (num_adm_permitted_opens
== 0) {
3608 for (i
= 0; i
< num_adm_permitted_opens
; i
++)
3609 if (permitted_adm_opens
[i
].host_to_connect
== NULL
)
3612 printf(" %s:%d", permitted_adm_opens
[i
].host_to_connect
,
3613 permitted_adm_opens
[i
].port_to_connect
);
3617 /* returns port number, FWD_PERMIT_ANY_PORT or -1 on error */
3619 permitopen_port(const char *p
)
3623 if (strcmp(p
, "*") == 0)
3624 return FWD_PERMIT_ANY_PORT
;
3625 if ((port
= a2port(p
)) > 0)
3630 /* Try to start non-blocking connect to next host in cctx list */
3632 connect_next(struct channel_connect
*cctx
)
3634 int sock
, saved_errno
;
3635 struct sockaddr_un
*sunaddr
;
3636 char ntop
[NI_MAXHOST
], strport
[MAX(NI_MAXSERV
,sizeof(sunaddr
->sun_path
))];
3638 for (; cctx
->ai
; cctx
->ai
= cctx
->ai
->ai_next
) {
3639 switch (cctx
->ai
->ai_family
) {
3641 /* unix:pathname instead of host:port */
3642 sunaddr
= (struct sockaddr_un
*)cctx
->ai
->ai_addr
;
3643 strlcpy(ntop
, "unix", sizeof(ntop
));
3644 strlcpy(strport
, sunaddr
->sun_path
, sizeof(strport
));
3648 if (getnameinfo(cctx
->ai
->ai_addr
, cctx
->ai
->ai_addrlen
,
3649 ntop
, sizeof(ntop
), strport
, sizeof(strport
),
3650 NI_NUMERICHOST
|NI_NUMERICSERV
) != 0) {
3651 error("connect_next: getnameinfo failed");
3658 if ((sock
= socket(cctx
->ai
->ai_family
, cctx
->ai
->ai_socktype
,
3659 cctx
->ai
->ai_protocol
)) == -1) {
3660 if (cctx
->ai
->ai_next
== NULL
)
3661 error("socket: %.100s", strerror(errno
));
3663 verbose("socket: %.100s", strerror(errno
));
3666 if (set_nonblock(sock
) == -1)
3667 fatal("%s: set_nonblock(%d)", __func__
, sock
);
3668 if (connect(sock
, cctx
->ai
->ai_addr
,
3669 cctx
->ai
->ai_addrlen
) == -1 && errno
!= EINPROGRESS
) {
3670 debug("connect_next: host %.100s ([%.100s]:%s): "
3671 "%.100s", cctx
->host
, ntop
, strport
,
3673 saved_errno
= errno
;
3675 errno
= saved_errno
;
3676 continue; /* fail -- try next */
3678 if (cctx
->ai
->ai_family
!= AF_UNIX
)
3680 debug("connect_next: host %.100s ([%.100s]:%s) "
3681 "in progress, fd=%d", cctx
->host
, ntop
, strport
, sock
);
3682 cctx
->ai
= cctx
->ai
->ai_next
;
3689 channel_connect_ctx_free(struct channel_connect
*cctx
)
3693 if (cctx
->aitop
->ai_family
== AF_UNIX
)
3696 freeaddrinfo(cctx
->aitop
);
3698 memset(cctx
, 0, sizeof(*cctx
));
3701 /* Return CONNECTING channel to remote host:port or local socket path */
3703 connect_to(const char *name
, int port
, char *ctype
, char *rname
)
3705 struct addrinfo hints
;
3708 char strport
[NI_MAXSERV
];
3709 struct channel_connect cctx
;
3712 memset(&cctx
, 0, sizeof(cctx
));
3714 if (port
== PORT_STREAMLOCAL
) {
3715 struct sockaddr_un
*sunaddr
;
3716 struct addrinfo
*ai
;
3718 if (strlen(name
) > sizeof(sunaddr
->sun_path
)) {
3719 error("%.100s: %.100s", name
, strerror(ENAMETOOLONG
));
3724 * Fake up a struct addrinfo for AF_UNIX connections.
3725 * channel_connect_ctx_free() must check ai_family
3726 * and use free() not freeaddirinfo() for AF_UNIX.
3728 ai
= xmalloc(sizeof(*ai
) + sizeof(*sunaddr
));
3729 memset(ai
, 0, sizeof(*ai
) + sizeof(*sunaddr
));
3730 ai
->ai_addr
= (struct sockaddr
*)(ai
+ 1);
3731 ai
->ai_addrlen
= sizeof(*sunaddr
);
3732 ai
->ai_family
= AF_UNIX
;
3733 ai
->ai_socktype
= SOCK_STREAM
;
3734 ai
->ai_protocol
= PF_UNSPEC
;
3735 sunaddr
= (struct sockaddr_un
*)ai
->ai_addr
;
3736 sunaddr
->sun_family
= AF_UNIX
;
3737 strlcpy(sunaddr
->sun_path
, name
, sizeof(sunaddr
->sun_path
));
3740 memset(&hints
, 0, sizeof(hints
));
3741 hints
.ai_family
= IPv4or6
;
3742 hints
.ai_socktype
= SOCK_STREAM
;
3743 snprintf(strport
, sizeof strport
, "%d", port
);
3744 if ((gaierr
= getaddrinfo(name
, strport
, &hints
, &cctx
.aitop
)) != 0) {
3745 error("connect_to %.100s: unknown host (%s)", name
,
3746 ssh_gai_strerror(gaierr
));
3751 cctx
.host
= xstrdup(name
);
3753 cctx
.ai
= cctx
.aitop
;
3755 if ((sock
= connect_next(&cctx
)) == -1) {
3756 error("connect to %.100s port %d failed: %s",
3757 name
, port
, strerror(errno
));
3758 channel_connect_ctx_free(&cctx
);
3761 c
= channel_new(ctype
, SSH_CHANNEL_CONNECTING
, sock
, sock
, -1,
3762 CHAN_TCP_WINDOW_DEFAULT
, CHAN_TCP_PACKET_DEFAULT
, 0, rname
, 1);
3763 c
->connect_ctx
= cctx
;
3768 channel_connect_by_listen_address(const char *listen_host
,
3769 u_short listen_port
, char *ctype
, char *rname
)
3773 for (i
= 0; i
< num_permitted_opens
; i
++) {
3774 if (open_listen_match_tcpip(&permitted_opens
[i
], listen_host
,
3777 permitted_opens
[i
].host_to_connect
,
3778 permitted_opens
[i
].port_to_connect
, ctype
, rname
);
3781 error("WARNING: Server requests forwarding for unknown listen_port %d",
3787 channel_connect_by_listen_path(const char *path
, char *ctype
, char *rname
)
3791 for (i
= 0; i
< num_permitted_opens
; i
++) {
3792 if (open_listen_match_streamlocal(&permitted_opens
[i
], path
)) {
3794 permitted_opens
[i
].host_to_connect
,
3795 permitted_opens
[i
].port_to_connect
, ctype
, rname
);
3798 error("WARNING: Server requests forwarding for unknown path %.100s",
3803 /* Check if connecting to that port is permitted and connect. */
3805 channel_connect_to_port(const char *host
, u_short port
, char *ctype
, char *rname
)
3807 int i
, permit
, permit_adm
= 1;
3809 permit
= all_opens_permitted
;
3811 for (i
= 0; i
< num_permitted_opens
; i
++)
3812 if (open_match(&permitted_opens
[i
], host
, port
)) {
3818 if (num_adm_permitted_opens
> 0) {
3820 for (i
= 0; i
< num_adm_permitted_opens
; i
++)
3821 if (open_match(&permitted_adm_opens
[i
], host
, port
)) {
3827 if (!permit
|| !permit_adm
) {
3828 logit("Received request to connect to host %.100s port %d, "
3829 "but the request was denied.", host
, port
);
3832 return connect_to(host
, port
, ctype
, rname
);
3835 /* Check if connecting to that path is permitted and connect. */
3837 channel_connect_to_path(const char *path
, char *ctype
, char *rname
)
3839 int i
, permit
, permit_adm
= 1;
3841 permit
= all_opens_permitted
;
3843 for (i
= 0; i
< num_permitted_opens
; i
++)
3844 if (open_match(&permitted_opens
[i
], path
, PORT_STREAMLOCAL
)) {
3850 if (num_adm_permitted_opens
> 0) {
3852 for (i
= 0; i
< num_adm_permitted_opens
; i
++)
3853 if (open_match(&permitted_adm_opens
[i
], path
, PORT_STREAMLOCAL
)) {
3859 if (!permit
|| !permit_adm
) {
3860 logit("Received request to connect to path %.100s, "
3861 "but the request was denied.", path
);
3864 return connect_to(path
, PORT_STREAMLOCAL
, ctype
, rname
);
3868 channel_send_window_changes(void)
3873 for (i
= 0; i
< channels_alloc
; i
++) {
3874 if (channels
[i
] == NULL
|| !channels
[i
]->client_tty
||
3875 channels
[i
]->type
!= SSH_CHANNEL_OPEN
)
3877 if (ioctl(channels
[i
]->rfd
, TIOCGWINSZ
, &ws
) < 0)
3879 channel_request_start(i
, "window-change", 0);
3880 packet_put_int((u_int
)ws
.ws_col
);
3881 packet_put_int((u_int
)ws
.ws_row
);
3882 packet_put_int((u_int
)ws
.ws_xpixel
);
3883 packet_put_int((u_int
)ws
.ws_ypixel
);
3888 /* -- X11 forwarding */
3891 * Creates an internet domain socket for listening for X11 connections.
3892 * Returns 0 and a suitable display number for the DISPLAY variable
3893 * stored in display_numberp , or -1 if an error occurs.
3896 x11_create_display_inet(int x11_display_offset
, int x11_use_localhost
,
3897 int single_connection
, u_int
*display_numberp
, int **chanids
)
3900 int display_number
, sock
;
3902 struct addrinfo hints
, *ai
, *aitop
;
3903 char strport
[NI_MAXSERV
];
3904 int gaierr
, n
, num_socks
= 0, socks
[NUM_SOCKS
];
3906 if (chanids
== NULL
)
3909 for (display_number
= x11_display_offset
;
3910 display_number
< MAX_DISPLAYS
;
3912 port
= 6000 + display_number
;
3913 memset(&hints
, 0, sizeof(hints
));
3914 hints
.ai_family
= IPv4or6
;
3915 hints
.ai_flags
= x11_use_localhost
? 0: AI_PASSIVE
;
3916 hints
.ai_socktype
= SOCK_STREAM
;
3917 snprintf(strport
, sizeof strport
, "%d", port
);
3918 if ((gaierr
= getaddrinfo(NULL
, strport
, &hints
, &aitop
)) != 0) {
3919 error("getaddrinfo: %.100s", ssh_gai_strerror(gaierr
));
3922 for (ai
= aitop
; ai
; ai
= ai
->ai_next
) {
3923 if (ai
->ai_family
!= AF_INET
&& ai
->ai_family
!= AF_INET6
)
3925 sock
= socket(ai
->ai_family
, ai
->ai_socktype
,
3928 if ((errno
!= EINVAL
) && (errno
!= EAFNOSUPPORT
)
3930 && (errno
!= EPFNOSUPPORT
)
3933 error("socket: %.100s", strerror(errno
));
3934 freeaddrinfo(aitop
);
3937 debug("x11_create_display_inet: Socket family %d not supported",
3942 if (ai
->ai_family
== AF_INET6
)
3943 sock_set_v6only(sock
);
3944 if (x11_use_localhost
)
3945 channel_set_reuseaddr(sock
);
3946 if (bind(sock
, ai
->ai_addr
, ai
->ai_addrlen
) < 0) {
3947 debug2("bind port %d: %.100s", port
, strerror(errno
));
3950 for (n
= 0; n
< num_socks
; n
++) {
3956 socks
[num_socks
++] = sock
;
3957 if (num_socks
== NUM_SOCKS
)
3960 freeaddrinfo(aitop
);
3964 if (display_number
>= MAX_DISPLAYS
) {
3965 error("Failed to allocate internet-domain X11 display socket.");
3968 /* Start listening for connections on the socket. */
3969 for (n
= 0; n
< num_socks
; n
++) {
3971 if (listen(sock
, SSH_LISTEN_BACKLOG
) < 0) {
3972 error("listen: %.100s", strerror(errno
));
3978 /* Allocate a channel for each socket. */
3979 *chanids
= xcalloc(num_socks
+ 1, sizeof(**chanids
));
3980 for (n
= 0; n
< num_socks
; n
++) {
3982 nc
= channel_new("x11 listener",
3983 SSH_CHANNEL_X11_LISTENER
, sock
, sock
, -1,
3984 CHAN_X11_WINDOW_DEFAULT
, CHAN_X11_PACKET_DEFAULT
,
3985 0, "X11 inet listener", 1);
3986 nc
->single_connection
= single_connection
;
3987 (*chanids
)[n
] = nc
->self
;
3991 /* Return the display number for the DISPLAY environment variable. */
3992 *display_numberp
= display_number
;
3997 connect_local_xsocket_path(const char *pathname
)
4000 struct sockaddr_un addr
;
4002 sock
= socket(AF_UNIX
, SOCK_STREAM
, 0);
4004 error("socket: %.100s", strerror(errno
));
4005 memset(&addr
, 0, sizeof(addr
));
4006 addr
.sun_family
= AF_UNIX
;
4007 strlcpy(addr
.sun_path
, pathname
, sizeof addr
.sun_path
);
4008 if (connect(sock
, (struct sockaddr
*)&addr
, sizeof(addr
)) == 0)
4011 error("connect %.100s: %.100s", addr
.sun_path
, strerror(errno
));
4016 connect_local_xsocket(u_int dnr
)
4019 snprintf(buf
, sizeof buf
, _PATH_UNIX_X
, dnr
);
4020 return connect_local_xsocket_path(buf
);
4024 x11_connect_display(void)
4026 u_int display_number
;
4027 const char *display
;
4028 char buf
[1024], *cp
;
4029 struct addrinfo hints
, *ai
, *aitop
;
4030 char strport
[NI_MAXSERV
];
4031 int gaierr
, sock
= 0;
4033 /* Try to open a socket for the local X server. */
4034 display
= getenv("DISPLAY");
4036 error("DISPLAY not set.");
4040 * Now we decode the value of the DISPLAY variable and make a
4041 * connection to the real X server.
4044 /* Check if the display is from launchd. */
4046 if (strncmp(display
, "/tmp/launch", 11) == 0) {
4047 sock
= connect_local_xsocket_path(display
);
4051 /* OK, we now have a connection to the display. */
4056 * Check if it is a unix domain socket. Unix domain displays are in
4057 * one of the following formats: unix:d[.s], :d[.s], ::d[.s]
4059 if (strncmp(display
, "unix:", 5) == 0 ||
4060 display
[0] == ':') {
4061 /* Connect to the unix domain socket. */
4062 if (sscanf(strrchr(display
, ':') + 1, "%u", &display_number
) != 1) {
4063 error("Could not parse display number from DISPLAY: %.100s",
4067 /* Create a socket. */
4068 sock
= connect_local_xsocket(display_number
);
4072 /* OK, we now have a connection to the display. */
4076 * Connect to an inet socket. The DISPLAY value is supposedly
4077 * hostname:d[.s], where hostname may also be numeric IP address.
4079 strlcpy(buf
, display
, sizeof(buf
));
4080 cp
= strchr(buf
, ':');
4082 error("Could not find ':' in DISPLAY: %.100s", display
);
4086 /* buf now contains the host name. But first we parse the display number. */
4087 if (sscanf(cp
+ 1, "%u", &display_number
) != 1) {
4088 error("Could not parse display number from DISPLAY: %.100s",
4093 /* Look up the host address */
4094 memset(&hints
, 0, sizeof(hints
));
4095 hints
.ai_family
= IPv4or6
;
4096 hints
.ai_socktype
= SOCK_STREAM
;
4097 snprintf(strport
, sizeof strport
, "%u", 6000 + display_number
);
4098 if ((gaierr
= getaddrinfo(buf
, strport
, &hints
, &aitop
)) != 0) {
4099 error("%.100s: unknown host. (%s)", buf
,
4100 ssh_gai_strerror(gaierr
));
4103 for (ai
= aitop
; ai
; ai
= ai
->ai_next
) {
4104 /* Create a socket. */
4105 sock
= socket(ai
->ai_family
, ai
->ai_socktype
, ai
->ai_protocol
);
4107 debug2("socket: %.100s", strerror(errno
));
4110 /* Connect it to the display. */
4111 if (connect(sock
, ai
->ai_addr
, ai
->ai_addrlen
) < 0) {
4112 debug2("connect %.100s port %u: %.100s", buf
,
4113 6000 + display_number
, strerror(errno
));
4120 freeaddrinfo(aitop
);
4122 error("connect %.100s port %u: %.100s", buf
, 6000 + display_number
,
4131 * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
4132 * the remote channel number. We should do whatever we want, and respond
4133 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
4138 x11_input_open(int type
, u_int32_t seq
, void *ctxt
)
4141 int remote_id
, sock
= 0;
4144 debug("Received X11 open request.");
4146 remote_id
= packet_get_int();
4148 if (packet_get_protocol_flags() & SSH_PROTOFLAG_HOST_IN_FWD_OPEN
) {
4149 remote_host
= packet_get_string(NULL
);
4151 remote_host
= xstrdup("unknown (remote did not supply name)");
4155 /* Obtain a connection to the real X display. */
4156 sock
= x11_connect_display();
4158 /* Allocate a channel for this connection. */
4159 c
= channel_new("connected x11 socket",
4160 SSH_CHANNEL_X11_OPEN
, sock
, sock
, -1, 0, 0, 0,
4162 c
->remote_id
= remote_id
;
4167 /* Send refusal to the remote host. */
4168 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE
);
4169 packet_put_int(remote_id
);
4171 /* Send a confirmation to the remote host. */
4172 packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION
);
4173 packet_put_int(remote_id
);
4174 packet_put_int(c
->self
);
4180 /* dummy protocol handler that denies SSH-1 requests (agent/x11) */
4183 deny_input_open(int type
, u_int32_t seq
, void *ctxt
)
4185 int rchan
= packet_get_int();
4188 case SSH_SMSG_AGENT_OPEN
:
4189 error("Warning: ssh server tried agent forwarding.");
4191 case SSH_SMSG_X11_OPEN
:
4192 error("Warning: ssh server tried X11 forwarding.");
4195 error("deny_input_open: type %d", type
);
4198 error("Warning: this is probably a break-in attempt by a malicious server.");
4199 packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE
);
4200 packet_put_int(rchan
);
4206 * Requests forwarding of X11 connections, generates fake authentication
4207 * data, and enables authentication spoofing.
4208 * This should be called in the client only.
4211 x11_request_forwarding_with_spoofing(int client_session_id
, const char *disp
,
4212 const char *proto
, const char *data
, int want_reply
)
4214 u_int data_len
= (u_int
) strlen(data
) / 2;
4221 if (x11_saved_display
== NULL
)
4222 x11_saved_display
= xstrdup(disp
);
4223 else if (strcmp(disp
, x11_saved_display
) != 0) {
4224 error("x11_request_forwarding_with_spoofing: different "
4225 "$DISPLAY already forwarded");
4229 cp
= strchr(disp
, ':');
4231 cp
= strchr(cp
, '.');
4233 screen_number
= (u_int
)strtonum(cp
+ 1, 0, 400, NULL
);
4237 if (x11_saved_proto
== NULL
) {
4238 /* Save protocol name. */
4239 x11_saved_proto
= xstrdup(proto
);
4241 * Extract real authentication data and generate fake data
4242 * of the same length.
4244 x11_saved_data
= xmalloc(data_len
);
4245 x11_fake_data
= xmalloc(data_len
);
4246 for (i
= 0; i
< data_len
; i
++) {
4247 if (sscanf(data
+ 2 * i
, "%2x", &value
) != 1)
4248 fatal("x11_request_forwarding: bad "
4249 "authentication data: %.100s", data
);
4252 x11_saved_data
[i
] = value
;
4253 x11_fake_data
[i
] = rnd
& 0xff;
4256 x11_saved_data_len
= data_len
;
4257 x11_fake_data_len
= data_len
;
4260 /* Convert the fake data into hex. */
4261 new_data
= tohex(x11_fake_data
, data_len
);
4263 /* Send the request packet. */
4265 channel_request_start(client_session_id
, "x11-req", want_reply
);
4266 packet_put_char(0); /* XXX bool single connection */
4268 packet_start(SSH_CMSG_X11_REQUEST_FORWARDING
);
4270 packet_put_cstring(proto
);
4271 packet_put_cstring(new_data
);
4272 packet_put_int(screen_number
);
4274 packet_write_wait();
4279 /* -- agent forwarding */
4281 /* Sends a message to the server to request authentication fd forwarding. */
4284 auth_request_forwarding(void)
4286 packet_start(SSH_CMSG_AGENT_REQUEST_FORWARDING
);
4288 packet_write_wait();