1 /* $OpenBSD: channels.h,v 1.80 2005/10/10 10:23:08 djm 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.
43 /* Definitions for channel types. */
44 #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
45 #define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */
46 #define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */
47 #define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */
48 #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
49 #define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */
50 #define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */
51 #define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */
52 #define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */
53 #define SSH_CHANNEL_LARVAL 10 /* larval session */
54 #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
55 #define SSH_CHANNEL_CONNECTING 12
56 #define SSH_CHANNEL_DYNAMIC 13
57 #define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
58 #define SSH_CHANNEL_MAX_TYPE 15
60 #define SSH_CHANNEL_PATH_LEN 256
63 typedef struct Channel Channel;
65 typedef void channel_callback_fn(int, void *);
66 typedef int channel_filter_fn(struct Channel *, char *, int);
69 int type; /* channel type/state */
70 int self; /* my own channel identifier */
71 int remote_id; /* channel identifier for remote peer */
72 u_int istate; /* input from channel (state of receive half) */
73 u_int ostate; /* output to channel (state of transmit half) */
74 int flags; /* close sent/rcvd */
75 int rfd; /* read fd */
76 int wfd; /* write fd */
77 int efd; /* extended fd */
78 int sock; /* sock fd */
79 int ctl_fd; /* control fd (client sharing) */
80 int isatty; /* rfd is a tty */
81 int wfd_isatty; /* wfd is a tty */
82 int client_tty; /* (client) TTY has been requested */
83 int force_drain; /* force close on iEOF */
84 int delayed; /* fdset hack */
85 Buffer input; /* data read from socket, to be sent over
86 * encrypted connection */
87 Buffer output; /* data received over encrypted connection for
90 char path[SSH_CHANNEL_PATH_LEN];
91 /* path for unix domain sockets, or host name for forwards */
92 int listening_port; /* port being listened for forwards */
93 int host_port; /* remote port to connect for forwards */
94 char *remote_name; /* remote hostname */
97 u_int remote_maxpacket;
99 u_int local_window_max;
100 u_int local_consumed;
101 u_int local_maxpacket;
103 int single_connection;
105 char *ctype; /* type */
108 channel_callback_fn *confirm;
110 channel_callback_fn *detach_user;
114 channel_filter_fn *input_filter;
117 #define CHAN_EXTENDED_IGNORE 0
118 #define CHAN_EXTENDED_READ 1
119 #define CHAN_EXTENDED_WRITE 2
121 /* default window/packet sizes for tcp/x11-fwd-channel */
122 #define CHAN_SES_PACKET_DEFAULT (32*1024)
123 #define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT)
124 #define CHAN_TCP_PACKET_DEFAULT (32*1024)
125 #define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT)
126 #define CHAN_X11_PACKET_DEFAULT (16*1024)
127 #define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT)
129 /* possible input states */
130 #define CHAN_INPUT_OPEN 0
131 #define CHAN_INPUT_WAIT_DRAIN 1
132 #define CHAN_INPUT_WAIT_OCLOSE 2
133 #define CHAN_INPUT_CLOSED 3
135 /* possible output states */
136 #define CHAN_OUTPUT_OPEN 0
137 #define CHAN_OUTPUT_WAIT_DRAIN 1
138 #define CHAN_OUTPUT_WAIT_IEOF 2
139 #define CHAN_OUTPUT_CLOSED 3
141 #define CHAN_CLOSE_SENT 0x01
142 #define CHAN_CLOSE_RCVD 0x02
143 #define CHAN_EOF_SENT 0x04
144 #define CHAN_EOF_RCVD 0x08
146 /* check whether 'efd' is still in use */
147 #define CHANNEL_EFD_INPUT_ACTIVE(c) \
148 (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \
150 buffer_len(&c->extended) > 0))
151 #define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
152 (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \
153 c->efd != -1 && (!(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD)) || \
154 buffer_len(&c->extended) > 0))
156 /* channel management */
158 Channel *channel_lookup(int);
159 Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int);
160 void channel_set_fds(int, int, int, int, int, int, u_int);
161 void channel_free(Channel *);
162 void channel_free_all(void);
163 void channel_stop_listening(void);
165 void channel_send_open(int);
166 void channel_request_start(int, char *, int);
167 void channel_register_cleanup(int, channel_callback_fn *, int);
168 void channel_register_confirm(int, channel_callback_fn *, void *);
169 void channel_register_filter(int, channel_filter_fn *);
170 void channel_cancel_cleanup(int);
171 int channel_close_fd(int *);
172 void channel_send_window_changes(void);
174 /* protocol handler */
176 void channel_input_close(int, u_int32_t, void *);
177 void channel_input_close_confirmation(int, u_int32_t, void *);
178 void channel_input_data(int, u_int32_t, void *);
179 void channel_input_extended_data(int, u_int32_t, void *);
180 void channel_input_ieof(int, u_int32_t, void *);
181 void channel_input_oclose(int, u_int32_t, void *);
182 void channel_input_open_confirmation(int, u_int32_t, void *);
183 void channel_input_open_failure(int, u_int32_t, void *);
184 void channel_input_port_open(int, u_int32_t, void *);
185 void channel_input_window_adjust(int, u_int32_t, void *);
187 /* file descriptor handling (read/write) */
189 void channel_prepare_select(fd_set **, fd_set **, int *, u_int*, int);
190 void channel_after_select(fd_set *, fd_set *);
191 void channel_output_poll(void);
193 int channel_not_very_much_buffered_data(void);
194 void channel_close_all(void);
195 int channel_still_open(void);
196 char *channel_open_message(void);
197 int channel_find_open(void);
200 void channel_set_af(int af);
201 void channel_permit_all_opens(void);
202 void channel_add_permitted_opens(char *, int);
203 void channel_clear_permitted_opens(void);
204 void channel_input_port_forward_request(int, int);
205 int channel_connect_to(const char *, u_short);
206 int channel_connect_by_listen_address(u_short);
207 void channel_request_remote_forwarding(const char *, u_short,
208 const char *, u_short);
209 int channel_setup_local_fwd_listener(const char *, u_short,
210 const char *, u_short, int);
211 void channel_request_rforward_cancel(const char *host, u_short port);
212 int channel_setup_remote_fwd_listener(const char *, u_short, int);
213 int channel_cancel_rport_listener(const char *, u_short);
217 int x11_connect_display(void);
218 int x11_create_display_inet(int, int, int, u_int *, int **);
219 void x11_input_open(int, u_int32_t, void *);
220 void x11_request_forwarding_with_spoofing(int, const char *, const char *,
222 void deny_input_open(int, u_int32_t, void *);
224 /* agent forwarding */
226 void auth_request_forwarding(void);
230 int chan_is_dead(Channel *, int);
231 void chan_mark_dead(Channel *);
235 void chan_rcvd_oclose(Channel *);
236 void chan_read_failed(Channel *);
237 void chan_ibuf_empty(Channel *);
239 void chan_rcvd_ieof(Channel *);
240 void chan_write_failed(Channel *);
241 void chan_obuf_empty(Channel *);