2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
6 * As far as I am concerned, the code I have written for this software
7 * can be used freely for any purpose. Any derived versions of this
8 * software must be clearly marked as such, and if the derived work is
9 * incompatible with the protocol description in the RFC file, it must be
10 * called by a name other than "ssh" or "Secure Shell".
13 * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
15 * Redistribution and use in source and binary forms, with or without
16 * modification, are permitted provided that the following conditions
18 * 1. Redistributions of source code must retain the above copyright
19 * notice, this list of conditions and the following disclaimer.
20 * 2. Redistributions in binary form must reproduce the above copyright
21 * notice, this list of conditions and the following disclaimer in the
22 * documentation and/or other materials provided with the distribution.
24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 /* RCSID("$OpenBSD: channels.h,v 1.51 2001/11/07 22:53:21 markus Exp $"); */
42 /* Definitions for channel types. */
43 #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
44 #define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */
45 #define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */
46 #define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */
47 #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
48 #define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */
49 #define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */
50 #define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */
51 #define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */
52 #define SSH_CHANNEL_LARVAL 10 /* larval session */
53 #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
54 #define SSH_CHANNEL_CONNECTING 12
55 #define SSH_CHANNEL_DYNAMIC 13
56 #define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
57 #define SSH_CHANNEL_MAX_TYPE 15
59 #define SSH_CHANNEL_PATH_LEN 256
62 typedef struct Channel Channel;
64 typedef void channel_callback_fn(int, void *);
65 typedef int channel_filter_fn(struct Channel *, char *, int);
68 int type; /* channel type/state */
69 int self; /* my own channel identifier */
70 int remote_id; /* channel identifier for remote peer */
71 int istate; /* input from channel (state of receive half) */
72 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 isatty; /* rfd is a tty */
79 int force_drain; /* force close on iEOF */
80 int delayed; /* fdset hack */
81 Buffer input; /* data read from socket, to be sent over
82 * encrypted connection */
83 Buffer output; /* data received over encrypted connection for
86 char path[SSH_CHANNEL_PATH_LEN];
87 /* path for unix domain sockets, or host name for forwards */
88 int listening_port; /* port being listened for forwards */
89 int host_port; /* remote port to connect for forwards */
90 char *remote_name; /* remote hostname */
100 char *ctype; /* type */
103 channel_callback_fn *cb_fn;
106 channel_callback_fn *detach_user;
109 channel_filter_fn *input_filter;
112 #define CHAN_EXTENDED_IGNORE 0
113 #define CHAN_EXTENDED_READ 1
114 #define CHAN_EXTENDED_WRITE 2
116 /* default window/packet sizes for tcp/x11-fwd-channel */
117 #define CHAN_SES_WINDOW_DEFAULT (32*1024)
118 #define CHAN_SES_PACKET_DEFAULT (CHAN_SES_WINDOW_DEFAULT/2)
119 #define CHAN_TCP_WINDOW_DEFAULT (32*1024)
120 #define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2)
121 #define CHAN_X11_WINDOW_DEFAULT (4*1024)
122 #define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2)
124 /* possible input states */
125 #define CHAN_INPUT_OPEN 0x01
126 #define CHAN_INPUT_WAIT_DRAIN 0x02
127 #define CHAN_INPUT_WAIT_OCLOSE 0x04
128 #define CHAN_INPUT_CLOSED 0x08
130 /* possible output states */
131 #define CHAN_OUTPUT_OPEN 0x10
132 #define CHAN_OUTPUT_WAIT_DRAIN 0x20
133 #define CHAN_OUTPUT_WAIT_IEOF 0x40
134 #define CHAN_OUTPUT_CLOSED 0x80
136 #define CHAN_CLOSE_SENT 0x01
137 #define CHAN_CLOSE_RCVD 0x02
139 /* channel management */
141 Channel *channel_lookup(int);
142 Channel *channel_new(char *, int, int, int, int, int, int, int, char *, int);
143 void channel_set_fds(int, int, int, int, int, int);
144 void channel_free(Channel *);
145 void channel_free_all(void);
146 void channel_stop_listening(void);
148 void channel_send_open(int);
149 void channel_request(int, char *, int);
150 void channel_request_start(int, char *, int);
151 void channel_register_callback(int, int mtype, channel_callback_fn *, void *);
152 void channel_register_cleanup(int, channel_callback_fn *);
153 void channel_register_filter(int, channel_filter_fn *);
154 void channel_cancel_cleanup(int);
155 int channel_close_fd(int *);
157 /* protocol handler */
159 void channel_input_channel_request(int, int, void *);
160 void channel_input_close(int, int, void *);
161 void channel_input_close_confirmation(int, int, void *);
162 void channel_input_data(int, int, void *);
163 void channel_input_extended_data(int, int, void *);
164 void channel_input_ieof(int, int, void *);
165 void channel_input_oclose(int, int, void *);
166 void channel_input_open_confirmation(int, int, void *);
167 void channel_input_open_failure(int, int, void *);
168 void channel_input_port_open(int, int, void *);
169 void channel_input_window_adjust(int, int, void *);
171 /* file descriptor handling (read/write) */
173 void channel_prepare_select(fd_set **, fd_set **, int *, int*, int);
174 void channel_after_select(fd_set *, fd_set *);
175 void channel_output_poll(void);
177 int channel_not_very_much_buffered_data(void);
178 void channel_close_all(void);
179 int channel_still_open(void);
180 char *channel_open_message(void);
181 int channel_find_open(void);
184 void channel_set_af(int af);
185 void channel_permit_all_opens(void);
186 void channel_add_permitted_opens(char *, int);
187 void channel_clear_permitted_opens(void);
188 void channel_input_port_forward_request(int, int);
189 int channel_connect_to(const char *, u_short);
190 int channel_connect_by_listen_address(u_short);
191 void channel_request_remote_forwarding(u_short, const char *, u_short);
192 int channel_request_local_forwarding(u_short, const char *, u_short, int);
194 channel_request_forwarding(const char *, u_short, const char *, u_short, int,
199 int x11_connect_display(void);
200 char *x11_create_display(int);
201 char *x11_create_display_inet(int, int);
202 void x11_input_open(int, int, void *);
203 void x11_request_forwarding(void);
204 void x11_request_forwarding_with_spoofing(int, const char *, const char *);
205 void deny_input_open(int, int, void *);
207 /* agent forwarding */
209 void auth_request_forwarding(void);
210 char *auth_get_socket_name(void);
211 void auth_sock_cleanup_proc(void *);
212 int auth_input_request_forwarding(struct passwd *);
213 void auth_input_open_request(int, int, void *);
217 int chan_is_dead(Channel *, int);
218 void chan_mark_dead(Channel *);
219 void chan_init_iostates(Channel *);
220 void chan_init(void);
222 typedef void chan_event_fn(Channel *);
224 /* for the input state */
225 extern chan_event_fn *chan_rcvd_oclose;
226 extern chan_event_fn *chan_read_failed;
227 extern chan_event_fn *chan_ibuf_empty;
229 /* for the output state */
230 extern chan_event_fn *chan_rcvd_ieof;
231 extern chan_event_fn *chan_write_failed;
232 extern chan_event_fn *chan_obuf_empty;