1 /* $OpenBSD: channels.h,v 1.88 2006/08/03 03:34:42 deraadt Exp $ */
4 * Author: Tatu Ylonen <ylo@cs.hut.fi>
5 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
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".
15 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
17 * Redistribution and use in source and binary forms, with or without
18 * modification, are permitted provided that the following conditions
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.
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.
41 /* Definitions for channel types. */
42 #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
43 #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 */
46 #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
47 #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 */
52 #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
53 #define SSH_CHANNEL_CONNECTING 12
54 #define SSH_CHANNEL_DYNAMIC 13
55 #define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
56 #define SSH_CHANNEL_MAX_TYPE 15
58 #define SSH_CHANNEL_PATH_LEN 256
61 typedef struct Channel Channel;
63 typedef void channel_callback_fn(int, void *);
64 typedef int channel_infilter_fn(struct Channel *, char *, int);
65 typedef u_char *channel_outfilter_fn(struct Channel *, u_char **, u_int *);
68 int type; /* channel type/state */
69 int self; /* my own channel identifier */
70 int remote_id; /* channel identifier for remote peer */
71 u_int istate; /* input from channel (state of receive half) */
72 u_int ostate; /* output to channel (state of transmit half) */
73 int flags; /* close sent/rcvd */
74 int rfd; /* read fd */
75 int wfd; /* write fd */
76 int efd; /* extended fd */
77 int sock; /* sock fd */
78 int ctl_fd; /* control fd (client sharing) */
79 int isatty; /* rfd is a tty */
80 int wfd_isatty; /* wfd is a tty */
81 int client_tty; /* (client) TTY has been requested */
82 int force_drain; /* force close on iEOF */
83 int delayed; /* fdset hack */
84 Buffer input; /* data read from socket, to be sent over
85 * encrypted connection */
86 Buffer output; /* data received over encrypted connection for
89 char path[SSH_CHANNEL_PATH_LEN];
90 /* path for unix domain sockets, or host name for forwards */
91 int listening_port; /* port being listened for forwards */
92 int host_port; /* remote port to connect for forwards */
93 char *remote_name; /* remote hostname */
96 u_int remote_maxpacket;
98 u_int local_window_max;
100 u_int local_maxpacket;
103 int single_connection;
106 char *ctype; /* type */
109 channel_callback_fn *confirm;
111 channel_callback_fn *detach_user;
115 channel_infilter_fn *input_filter;
116 channel_outfilter_fn *output_filter;
118 int datagram; /* keep boundaries */
121 #define CHAN_EXTENDED_IGNORE 0
122 #define CHAN_EXTENDED_READ 1
123 #define CHAN_EXTENDED_WRITE 2
125 /* default window/packet sizes for tcp/x11-fwd-channel */
126 #define CHAN_SES_PACKET_DEFAULT (32*1024)
127 #define CHAN_SES_WINDOW_DEFAULT_HPN (160*CHAN_TCP_PACKET_DEFAULT)
128 #define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT)
130 #define CHAN_TCP_PACKET_DEFAULT (32*1024)
131 #define CHAN_TCP_WINDOW_DEFAULT_HPN (160*CHAN_TCP_PACKET_DEFAULT)
132 #define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT)
134 #define CHAN_X11_PACKET_DEFAULT (16*1024)
135 #define CHAN_X11_WINDOW_DEFAULT_HPN (4*CHAN_X11_PACKET_DEFAULT)
136 #define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT)
138 /* possible input states */
139 #define CHAN_INPUT_OPEN 0
140 #define CHAN_INPUT_WAIT_DRAIN 1
141 #define CHAN_INPUT_WAIT_OCLOSE 2
142 #define CHAN_INPUT_CLOSED 3
144 /* possible output states */
145 #define CHAN_OUTPUT_OPEN 0
146 #define CHAN_OUTPUT_WAIT_DRAIN 1
147 #define CHAN_OUTPUT_WAIT_IEOF 2
148 #define CHAN_OUTPUT_CLOSED 3
150 #define CHAN_CLOSE_SENT 0x01
151 #define CHAN_CLOSE_RCVD 0x02
152 #define CHAN_EOF_SENT 0x04
153 #define CHAN_EOF_RCVD 0x08
155 #define CHAN_RBUF 16*1024
157 /* check whether 'efd' is still in use */
158 #define CHANNEL_EFD_INPUT_ACTIVE(c) \
159 (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \
161 buffer_len(&c->extended) > 0))
162 #define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
163 (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \
164 c->efd != -1 && (!(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD)) || \
165 buffer_len(&c->extended) > 0))
167 /* channel management */
169 Channel *channel_by_id(int);
170 Channel *channel_lookup(int);
171 Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int);
172 void channel_set_fds(int, int, int, int, int, int, u_int);
173 void channel_free(Channel *);
174 void channel_free_all(void);
175 void channel_stop_listening(void);
177 void channel_send_open(int);
178 void channel_request_start(int, char *, int);
179 void channel_register_cleanup(int, channel_callback_fn *, int);
180 void channel_register_confirm(int, channel_callback_fn *, void *);
181 void channel_register_filter(int, channel_infilter_fn *, channel_outfilter_fn *);
182 void channel_cancel_cleanup(int);
183 int channel_close_fd(int *);
184 void channel_send_window_changes(void);
186 /* protocol handler */
188 void channel_input_close(int, u_int32_t, void *);
189 void channel_input_close_confirmation(int, u_int32_t, void *);
190 void channel_input_data(int, u_int32_t, void *);
191 void channel_input_extended_data(int, u_int32_t, void *);
192 void channel_input_ieof(int, u_int32_t, void *);
193 void channel_input_oclose(int, u_int32_t, void *);
194 void channel_input_open_confirmation(int, u_int32_t, void *);
195 void channel_input_open_failure(int, u_int32_t, void *);
196 void channel_input_port_open(int, u_int32_t, void *);
197 void channel_input_window_adjust(int, u_int32_t, void *);
199 /* file descriptor handling (read/write) */
201 void channel_prepare_select(fd_set **, fd_set **, int *, u_int*, int);
202 void channel_after_select(fd_set *, fd_set *);
203 void channel_output_poll(void);
205 int channel_not_very_much_buffered_data(void);
206 void channel_close_all(void);
207 int channel_still_open(void);
208 char *channel_open_message(void);
209 int channel_find_open(void);
212 void channel_set_af(int af);
213 void channel_permit_all_opens(void);
214 void channel_add_permitted_opens(char *, int);
215 int channel_add_adm_permitted_opens(char *, int);
216 void channel_clear_permitted_opens(void);
217 void channel_clear_adm_permitted_opens(void);
218 int channel_input_port_forward_request(int, int, int, int);
219 int channel_connect_to(const char *, u_short);
220 int channel_connect_by_listen_address(u_short);
221 int channel_request_remote_forwarding(const char *, u_short,
222 const char *, u_short);
223 int channel_setup_local_fwd_listener(const char *, u_short,
224 const char *, u_short, int, int, int);
225 void channel_request_rforward_cancel(const char *host, u_short port);
226 int channel_setup_remote_fwd_listener(const char *, u_short, int, int, int);
227 int channel_cancel_rport_listener(const char *, u_short);
231 int x11_connect_display(void);
232 int x11_create_display_inet(int, int, int, u_int *, int **, int, int);
233 void x11_input_open(int, u_int32_t, void *);
234 void x11_request_forwarding_with_spoofing(int, const char *, const char *,
236 void deny_input_open(int, u_int32_t, void *);
238 /* agent forwarding */
240 void auth_request_forwarding(void);
244 int chan_is_dead(Channel *, int);
245 void chan_mark_dead(Channel *);
249 void chan_rcvd_oclose(Channel *);
250 void chan_read_failed(Channel *);
251 void chan_ibuf_empty(Channel *);
253 void chan_rcvd_ieof(Channel *);
254 void chan_write_failed(Channel *);
255 void chan_obuf_empty(Channel *);