blob: 6f316c824a73e940194d5c1883dd6c94f270374c [file] [log] [blame]
Darren Tucker1338b9e2011-10-02 18:57:35 +11001/* $OpenBSD: channels.h,v 1.108 2011/09/23 00:22:04 dtucker Exp $ */
Ben Lindstrom05764b92002-03-05 01:53:02 +00002
Damien Millere4340be2000-09-16 13:29:08 +11003/*
4 * Author: Tatu Ylonen <ylo@cs.hut.fi>
5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * All rights reserved
7 *
8 * As far as I am concerned, the code I have written for this software
9 * can be used freely for any purpose. Any derived versions of this
10 * software must be clearly marked as such, and if the derived work is
11 * incompatible with the protocol description in the RFC file, it must be
12 * called by a name other than "ssh" or "Secure Shell".
13 */
14/*
Damien Millerb51ed392002-01-22 23:29:03 +110015 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
Damien Millere4340be2000-09-16 13:29:08 +110016 *
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
19 * are met:
20 * 1. Redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer.
22 * 2. Redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
27 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
28 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
29 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
30 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
31 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
35 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 */
Damien Millerd4a8b7e1999-10-27 13:42:43 +100037
Ben Lindstrome9c99912001-06-09 00:41:05 +000038#ifndef CHANNEL_H
39#define CHANNEL_H
Damien Millerd4a8b7e1999-10-27 13:42:43 +100040
41/* Definitions for channel types. */
Damien Miller5428f641999-11-25 11:54:57 +110042#define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
Damien Miller95def091999-11-25 00:26:21 +110043#define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */
44#define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */
45#define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */
Damien Miller5428f641999-11-25 11:54:57 +110046#define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
Damien Millerb38eff82000-04-01 11:09:21 +100047#define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */
48#define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */
49#define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */
50#define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */
51#define SSH_CHANNEL_LARVAL 10 /* larval session */
Damien Miller0bc1bd82000-11-13 22:57:25 +110052#define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
Ben Lindstrom7ad97102000-12-06 01:42:49 +000053#define SSH_CHANNEL_CONNECTING 12
Ben Lindstrom3bb4f9d2001-04-08 18:30:26 +000054#define SSH_CHANNEL_DYNAMIC 13
Ben Lindstromc0dee1a2001-06-05 20:52:50 +000055#define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
Damien Millere1537f92010-01-26 13:26:22 +110056#define SSH_CHANNEL_MUX_LISTENER 15 /* Listener for mux conn. */
57#define SSH_CHANNEL_MUX_CLIENT 16 /* Conn. to mux slave */
58#define SSH_CHANNEL_MAX_TYPE 17
Damien Millerd4a8b7e1999-10-27 13:42:43 +100059
Damien Millerff773642011-09-22 21:39:48 +100060#define CHANNEL_CANCEL_PORT_STATIC -1
61
Damien Millerad833b32000-08-23 10:46:23 +100062struct Channel;
63typedef struct Channel Channel;
Damien Millerd4a8b7e1999-10-27 13:42:43 +100064
Damien Millerd530f5f2010-05-21 14:57:10 +100065typedef void channel_open_fn(int, int, void *);
Ben Lindstrom16ae3d02001-07-04 04:02:36 +000066typedef void channel_callback_fn(int, void *);
Damien Miller077b2382005-12-31 16:22:32 +110067typedef int channel_infilter_fn(struct Channel *, char *, int);
Darren Tucker84c56f52008-06-13 04:55:46 +100068typedef void channel_filter_cleanup_fn(int, void *);
Damien Miller077b2382005-12-31 16:22:32 +110069typedef u_char *channel_outfilter_fn(struct Channel *, u_char **, u_int *);
Damien Millerad833b32000-08-23 10:46:23 +100070
Damien Millerb84886b2008-05-19 15:05:07 +100071/* Channel success/failure callbacks */
72typedef void channel_confirm_cb(int, struct Channel *, void *);
73typedef void channel_confirm_abandon_cb(struct Channel *, void *);
74struct channel_confirm {
75 TAILQ_ENTRY(channel_confirm) entry;
76 channel_confirm_cb *cb;
77 channel_confirm_abandon_cb *abandon_cb;
78 void *ctx;
79};
80TAILQ_HEAD(channel_confirms, channel_confirm);
81
Damien Millerbd740252008-05-19 15:37:09 +100082/* Context for non-blocking connects */
83struct channel_connect {
84 char *host;
85 int port;
86 struct addrinfo *ai, *aitop;
87};
88
Damien Millere1537f92010-01-26 13:26:22 +110089/* Callbacks for mux channels back into client-specific code */
90typedef int mux_callback_fn(struct Channel *);
91
Damien Millerad833b32000-08-23 10:46:23 +100092struct Channel {
Damien Miller95def091999-11-25 00:26:21 +110093 int type; /* channel type/state */
94 int self; /* my own channel identifier */
95 int remote_id; /* channel identifier for remote peer */
Damien Millerabea8ee2002-01-22 23:27:11 +110096 u_int istate; /* input from channel (state of receive half) */
97 u_int ostate; /* output to channel (state of transmit half) */
Damien Miller33b13562000-04-04 14:38:59 +100098 int flags; /* close sent/rcvd */
Damien Millerb38eff82000-04-01 11:09:21 +100099 int rfd; /* read fd */
100 int wfd; /* write fd */
101 int efd; /* extended fd */
102 int sock; /* sock fd */
Damien Millere1537f92010-01-26 13:26:22 +1100103 int ctl_chan; /* control channel (multiplexed connections) */
Damien Miller79438cc2001-02-16 12:34:57 +1100104 int isatty; /* rfd is a tty */
Ben Lindstrombeb5f332002-07-22 15:28:53 +0000105 int wfd_isatty; /* wfd is a tty */
Darren Tucker5d78de62004-11-05 20:35:44 +1100106 int client_tty; /* (client) TTY has been requested */
Damien Miller4623a752001-10-10 15:03:58 +1000107 int force_drain; /* force close on iEOF */
Darren Tucker876045b2010-01-08 17:08:00 +1100108 int delayed; /* post-select handlers for newly created
109 * channels are delayed until the first call
110 * to a matching pre-select handler.
111 * this way post-select handlers are not
112 * accidenly called if a FD gets reused */
Damien Miller95def091999-11-25 00:26:21 +1100113 Buffer input; /* data read from socket, to be sent over
114 * encrypted connection */
115 Buffer output; /* data received over encrypted connection for
116 * send on socket */
Damien Millerb38eff82000-04-01 11:09:21 +1000117 Buffer extended;
Damien Millera1c1b6c2009-01-28 16:29:49 +1100118 char *path;
Ben Lindstrom99c73b32001-05-05 04:09:47 +0000119 /* path for unix domain sockets, or host name for forwards */
Damien Miller95def091999-11-25 00:26:21 +1100120 int listening_port; /* port being listened for forwards */
Damien Millerf6dff7c2011-09-22 21:38:52 +1000121 char *listening_addr; /* addr being listened for forwards */
Damien Miller95def091999-11-25 00:26:21 +1100122 int host_port; /* remote port to connect for forwards */
123 char *remote_name; /* remote hostname */
Damien Millerb38eff82000-04-01 11:09:21 +1000124
Ben Lindstrom4fed2be2002-06-25 23:17:36 +0000125 u_int remote_window;
126 u_int remote_maxpacket;
127 u_int local_window;
128 u_int local_window_max;
129 u_int local_consumed;
130 u_int local_maxpacket;
Damien Millerb38eff82000-04-01 11:09:21 +1000131 int extended_usage;
Damien Millere7378562001-12-21 14:58:35 +1100132 int single_connection;
Damien Millerb38eff82000-04-01 11:09:21 +1000133
134 char *ctype; /* type */
135
Damien Millere247cc42000-05-07 12:03:14 +1000136 /* callback */
Damien Millerd530f5f2010-05-21 14:57:10 +1000137 channel_open_fn *open_confirm;
Damien Millerb84886b2008-05-19 15:05:07 +1000138 void *open_confirm_ctx;
Damien Miller39eda6e2005-11-05 14:52:50 +1100139 channel_callback_fn *detach_user;
140 int detach_close;
Damien Millerb84886b2008-05-19 15:05:07 +1000141 struct channel_confirms status_confirms;
Damien Millerad833b32000-08-23 10:46:23 +1000142
143 /* filter */
Damien Miller077b2382005-12-31 16:22:32 +1100144 channel_infilter_fn *input_filter;
145 channel_outfilter_fn *output_filter;
Darren Tucker2fb66ca2008-06-13 04:49:33 +1000146 void *filter_ctx;
Darren Tucker84c56f52008-06-13 04:55:46 +1000147 channel_filter_cleanup_fn *filter_cleanup;
Damien Millerd27b9472005-12-13 19:29:02 +1100148
Damien Millerbd740252008-05-19 15:37:09 +1000149 /* keep boundaries */
150 int datagram;
151
152 /* non-blocking connect */
153 struct channel_connect connect_ctx;
Damien Millere1537f92010-01-26 13:26:22 +1100154
155 /* multiplexing protocol hook, called for each packet received */
156 mux_callback_fn *mux_rcb;
157 void *mux_ctx;
Damien Millerd530f5f2010-05-21 14:57:10 +1000158 int mux_pause;
Damien Millerad833b32000-08-23 10:46:23 +1000159};
Damien Millerb38eff82000-04-01 11:09:21 +1000160
161#define CHAN_EXTENDED_IGNORE 0
162#define CHAN_EXTENDED_READ 1
163#define CHAN_EXTENDED_WRITE 2
164
Damien Millere4340be2000-09-16 13:29:08 +1100165/* default window/packet sizes for tcp/x11-fwd-channel */
Damien Miller19a59452002-02-19 15:20:57 +1100166#define CHAN_SES_PACKET_DEFAULT (32*1024)
Darren Tucker395ecc22007-06-12 23:38:53 +1000167#define CHAN_SES_WINDOW_DEFAULT (64*CHAN_SES_PACKET_DEFAULT)
Damien Miller19a59452002-02-19 15:20:57 +1100168#define CHAN_TCP_PACKET_DEFAULT (32*1024)
Darren Tucker395ecc22007-06-12 23:38:53 +1000169#define CHAN_TCP_WINDOW_DEFAULT (64*CHAN_TCP_PACKET_DEFAULT)
Damien Miller19a59452002-02-19 15:20:57 +1100170#define CHAN_X11_PACKET_DEFAULT (16*1024)
171#define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT)
Damien Millere4340be2000-09-16 13:29:08 +1100172
Ben Lindstrome9c99912001-06-09 00:41:05 +0000173/* possible input states */
Damien Millerabea8ee2002-01-22 23:27:11 +1100174#define CHAN_INPUT_OPEN 0
175#define CHAN_INPUT_WAIT_DRAIN 1
176#define CHAN_INPUT_WAIT_OCLOSE 2
177#define CHAN_INPUT_CLOSED 3
Damien Millere4340be2000-09-16 13:29:08 +1100178
Ben Lindstrome9c99912001-06-09 00:41:05 +0000179/* possible output states */
Damien Millerabea8ee2002-01-22 23:27:11 +1100180#define CHAN_OUTPUT_OPEN 0
181#define CHAN_OUTPUT_WAIT_DRAIN 1
182#define CHAN_OUTPUT_WAIT_IEOF 2
183#define CHAN_OUTPUT_CLOSED 3
Ben Lindstrome9c99912001-06-09 00:41:05 +0000184
185#define CHAN_CLOSE_SENT 0x01
186#define CHAN_CLOSE_RCVD 0x02
Ben Lindstromcf159442002-03-26 03:26:24 +0000187#define CHAN_EOF_SENT 0x04
188#define CHAN_EOF_RCVD 0x08
Damien Millere1537f92010-01-26 13:26:22 +1100189#define CHAN_LOCAL 0x10
Ben Lindstromcf159442002-03-26 03:26:24 +0000190
Damien Miller077b2382005-12-31 16:22:32 +1100191#define CHAN_RBUF 16*1024
192
Ben Lindstromcf159442002-03-26 03:26:24 +0000193/* check whether 'efd' is still in use */
194#define CHANNEL_EFD_INPUT_ACTIVE(c) \
195 (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \
196 (c->efd != -1 || \
197 buffer_len(&c->extended) > 0))
198#define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
199 (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \
Darren Tuckerce377c32005-07-14 17:05:51 +1000200 c->efd != -1 && (!(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD)) || \
Ben Lindstromcf159442002-03-26 03:26:24 +0000201 buffer_len(&c->extended) > 0))
Ben Lindstrome9c99912001-06-09 00:41:05 +0000202
Ben Lindstrome9c99912001-06-09 00:41:05 +0000203/* channel management */
204
Damien Millerd47c62a2005-12-13 19:33:57 +1100205Channel *channel_by_id(int);
Ben Lindstrom16ae3d02001-07-04 04:02:36 +0000206Channel *channel_lookup(int);
Ben Lindstrom4fed2be2002-06-25 23:17:36 +0000207Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int);
Damien Millerd310d512008-06-16 07:59:23 +1000208void channel_set_fds(int, int, int, int, int, int, int, u_int);
Ben Lindstrom809744e2001-07-04 05:26:06 +0000209void channel_free(Channel *);
210void channel_free_all(void);
Ben Lindstrom809744e2001-07-04 05:26:06 +0000211void channel_stop_listening(void);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000212
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000213void channel_send_open(int);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000214void channel_request_start(int, char *, int);
Damien Miller39eda6e2005-11-05 14:52:50 +1100215void channel_register_cleanup(int, channel_callback_fn *, int);
Damien Millerd530f5f2010-05-21 14:57:10 +1000216void channel_register_open_confirm(int, channel_open_fn *, void *);
Damien Millerb84886b2008-05-19 15:05:07 +1000217void channel_register_filter(int, channel_infilter_fn *,
Darren Tucker84c56f52008-06-13 04:55:46 +1000218 channel_outfilter_fn *, channel_filter_cleanup_fn *, void *);
Damien Millerb84886b2008-05-19 15:05:07 +1000219void channel_register_status_confirm(int, channel_confirm_cb *,
220 channel_confirm_abandon_cb *, void *);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000221void channel_cancel_cleanup(int);
Ben Lindstrom16d29d52001-07-18 16:01:46 +0000222int channel_close_fd(int *);
Damien Miller0e220db2004-06-15 10:34:08 +1000223void channel_send_window_changes(void);
Damien Millerb38eff82000-04-01 11:09:21 +1000224
Ben Lindstrome9c99912001-06-09 00:41:05 +0000225/* protocol handler */
Damien Millerb38eff82000-04-01 11:09:21 +1000226
Damien Miller630d6f42002-01-22 23:17:30 +1100227void channel_input_close(int, u_int32_t, void *);
228void channel_input_close_confirmation(int, u_int32_t, void *);
229void channel_input_data(int, u_int32_t, void *);
230void channel_input_extended_data(int, u_int32_t, void *);
231void channel_input_ieof(int, u_int32_t, void *);
232void channel_input_oclose(int, u_int32_t, void *);
233void channel_input_open_confirmation(int, u_int32_t, void *);
234void channel_input_open_failure(int, u_int32_t, void *);
235void channel_input_port_open(int, u_int32_t, void *);
236void channel_input_window_adjust(int, u_int32_t, void *);
Damien Millerb84886b2008-05-19 15:05:07 +1000237void channel_input_status_confirm(int, u_int32_t, void *);
Damien Millerb38eff82000-04-01 11:09:21 +1000238
Ben Lindstrome9c99912001-06-09 00:41:05 +0000239/* file descriptor handling (read/write) */
Damien Millerb38eff82000-04-01 11:09:21 +1000240
Darren Tuckerc7a6fc42004-08-13 21:18:00 +1000241void channel_prepare_select(fd_set **, fd_set **, int *, u_int*, int);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000242void channel_after_select(fd_set *, fd_set *);
243void channel_output_poll(void);
Damien Millerb38eff82000-04-01 11:09:21 +1000244
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000245int channel_not_very_much_buffered_data(void);
246void channel_close_all(void);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000247int channel_still_open(void);
248char *channel_open_message(void);
249int channel_find_open(void);
Damien Millerb38eff82000-04-01 11:09:21 +1000250
Ben Lindstrom908afed2001-10-03 17:34:59 +0000251/* tcp forwarding */
252void channel_set_af(int af);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000253void channel_permit_all_opens(void);
254void channel_add_permitted_opens(char *, int);
Damien Millera765cf42006-07-24 14:08:13 +1000255int channel_add_adm_permitted_opens(char *, int);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000256void channel_clear_permitted_opens(void);
Damien Miller9b439df2006-07-24 14:04:00 +1000257void channel_clear_adm_permitted_opens(void);
Darren Tuckere7140f22008-06-10 23:01:51 +1000258void channel_print_adm_permitted_opens(void);
Darren Tuckere7d4b192006-07-12 22:17:10 +1000259int channel_input_port_forward_request(int, int);
Damien Millerbd740252008-05-19 15:37:09 +1000260Channel *channel_connect_to(const char *, u_short, char *, char *);
Damien Millere1537f92010-01-26 13:26:22 +1100261Channel *channel_connect_stdio_fwd(const char*, u_short, int, int);
Damien Millerbd740252008-05-19 15:37:09 +1000262Channel *channel_connect_by_listen_address(u_short, char *, char *);
Darren Tuckere7d4b192006-07-12 22:17:10 +1000263int channel_request_remote_forwarding(const char *, u_short,
Damien Millerf91ee4c2005-03-01 21:24:33 +1100264 const char *, u_short);
265int channel_setup_local_fwd_listener(const char *, u_short,
266 const char *, u_short, int);
Damien Millerf6dff7c2011-09-22 21:38:52 +1000267int channel_request_rforward_cancel(const char *host, u_short port);
Damien Miller4bf648f2009-02-14 16:28:21 +1100268int channel_setup_remote_fwd_listener(const char *, u_short, int *, int);
Darren Tuckere7066df2004-05-24 10:18:05 +1000269int channel_cancel_rport_listener(const char *, u_short);
Damien Millerff773642011-09-22 21:39:48 +1000270int channel_cancel_lport_listener(const char *, u_short, int, int);
Darren Tucker1338b9e2011-10-02 18:57:35 +1100271int permitopen_port(const char *);
Damien Millerb38eff82000-04-01 11:09:21 +1000272
Ben Lindstrome9c99912001-06-09 00:41:05 +0000273/* x11 forwarding */
274
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000275int x11_connect_display(void);
Damien Miller2b9b0452005-07-17 17:19:24 +1000276int x11_create_display_inet(int, int, int, u_int *, int **);
Damien Miller630d6f42002-01-22 23:17:30 +1100277void x11_input_open(int, u_int32_t, void *);
Damien Miller17e7ed02005-06-17 12:54:33 +1000278void x11_request_forwarding_with_spoofing(int, const char *, const char *,
Damien Miller6d7b4372011-06-23 08:31:57 +1000279 const char *, int);
Damien Miller630d6f42002-01-22 23:17:30 +1100280void deny_input_open(int, u_int32_t, void *);
Damien Millerb38eff82000-04-01 11:09:21 +1000281
Ben Lindstrome9c99912001-06-09 00:41:05 +0000282/* agent forwarding */
283
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000284void auth_request_forwarding(void);
Damien Millerb38eff82000-04-01 11:09:21 +1000285
Ben Lindstrome9c99912001-06-09 00:41:05 +0000286/* channel close */
Damien Miller33b13562000-04-04 14:38:59 +1000287
Damien Miller3ec27592001-10-12 11:35:04 +1000288int chan_is_dead(Channel *, int);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000289void chan_mark_dead(Channel *);
Ben Lindstrom4cc240d2001-07-04 04:46:56 +0000290
Damien Miller5144df92002-01-22 23:28:45 +1100291/* channel events */
Ben Lindstrome9c99912001-06-09 00:41:05 +0000292
Damien Miller5144df92002-01-22 23:28:45 +1100293void chan_rcvd_oclose(Channel *);
Damien Millerbab9bd42008-05-19 16:06:47 +1000294void chan_rcvd_eow(Channel *); /* SSH2-only */
Damien Miller5144df92002-01-22 23:28:45 +1100295void chan_read_failed(Channel *);
296void chan_ibuf_empty(Channel *);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000297
Damien Miller5144df92002-01-22 23:28:45 +1100298void chan_rcvd_ieof(Channel *);
299void chan_write_failed(Channel *);
300void chan_obuf_empty(Channel *);
Ben Lindstrome9c99912001-06-09 00:41:05 +0000301
Damien Millerd4a8b7e1999-10-27 13:42:43 +1000302#endif