Annotation of src/usr.bin/ssh/channels.h, Revision 1.23
1.17 deraadt 1: /*
1.19 markus 2: * Author: Tatu Ylonen <ylo@cs.hut.fi>
3: * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
4: * All rights reserved
5: *
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".
11: */
12: /*
1.17 deraadt 13: * Copyright (c) 2000 Markus Friedl. All rights reserved.
14: *
15: * Redistribution and use in source and binary forms, with or without
16: * modification, are permitted provided that the following conditions
17: * are met:
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.
23: *
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.
34: */
1.23 ! markus 35: /* RCSID("$OpenBSD: channels.h,v 1.22 2000/10/27 07:48:22 markus Exp $"); */
1.2 markus 36:
1.1 markus 37: #ifndef CHANNELS_H
38: #define CHANNELS_H
39:
40: /* Definitions for channel types. */
1.6 markus 41: #define SSH_CHANNEL_FREE 0 /* This channel is free (unused). */
42: #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
1.5 deraadt 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 */
1.6 markus 46: #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
1.7 markus 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 */
1.23 ! markus 52: #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
! 53: #define SSH_CHANNEL_MAX_TYPE 12
1.1 markus 54:
1.6 markus 55: /*
56: * Data structure for channel data. This is iniailized in channel_allocate
57: * and cleared in channel_free.
58: */
1.16 markus 59: struct Channel;
60: typedef struct Channel Channel;
61:
1.7 markus 62: typedef void channel_callback_fn(int id, void *arg);
1.16 markus 63: typedef int channel_filter_fn(struct Channel *c, char *buf, int len);
1.1 markus 64:
1.16 markus 65: struct Channel {
1.5 deraadt 66: int type; /* channel type/state */
67: int self; /* my own channel identifier */
68: int remote_id; /* channel identifier for remote peer */
69: /* peer can be reached over encrypted connection, via packet-sent */
70: int istate; /* input from channel (state of receive half) */
71: int ostate; /* output to channel (state of transmit half) */
1.8 markus 72: int flags; /* close sent/rcvd */
1.7 markus 73: int rfd; /* read fd */
74: int wfd; /* write fd */
75: int efd; /* extended fd */
76: int sock; /* sock fd */
1.5 deraadt 77: Buffer input; /* data read from socket, to be sent over
78: * encrypted connection */
79: Buffer output; /* data received over encrypted connection for
80: * send on socket */
1.7 markus 81: Buffer extended;
1.5 deraadt 82: char path[200]; /* path for unix domain sockets, or host name
83: * for forwards */
84: int listening_port; /* port being listened for forwards */
85: int host_port; /* remote port to connect for forwards */
86: char *remote_name; /* remote hostname */
1.7 markus 87:
88: int remote_window;
89: int remote_maxpacket;
90: int local_window;
91: int local_window_max;
92: int local_consumed;
93: int local_maxpacket;
94: int extended_usage;
95:
96: char *ctype; /* type */
97:
1.11 markus 98: /* callback */
1.7 markus 99: channel_callback_fn *cb_fn;
100: void *cb_arg;
101: int cb_event;
102: channel_callback_fn *dettach_user;
1.15 markus 103:
104: /* filter */
105: channel_filter_fn *input_filter;
1.16 markus 106: };
1.7 markus 107:
108: #define CHAN_EXTENDED_IGNORE 0
109: #define CHAN_EXTENDED_READ 1
110: #define CHAN_EXTENDED_WRITE 2
1.18 markus 111:
112: /* default window/packet sizes for tcp/x11-fwd-channel */
113: #define CHAN_SES_WINDOW_DEFAULT (32*1024)
114: #define CHAN_SES_PACKET_DEFAULT (CHAN_SES_WINDOW_DEFAULT/2)
115: #define CHAN_TCP_WINDOW_DEFAULT (32*1024)
116: #define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2)
117: #define CHAN_X11_WINDOW_DEFAULT (4*1024)
118: #define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2)
119:
1.7 markus 120:
121: void channel_open(int id);
1.8 markus 122: void channel_request(int id, char *service, int wantconfirm);
123: void channel_request_start(int id, char *service, int wantconfirm);
124: void channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg);
125: void channel_register_cleanup(int id, channel_callback_fn *fn);
1.15 markus 126: void channel_register_filter(int id, channel_filter_fn *fn);
1.8 markus 127: void channel_cancel_cleanup(int id);
1.7 markus 128: Channel *channel_lookup(int id);
129:
130: int
131: channel_new(char *ctype, int type, int rfd, int wfd, int efd,
1.21 markus 132: int window, int maxpack, int extended_usage, char *remote_name,
133: int nonblock);
134: void
135: channel_set_fds(int id, int rfd, int wfd, int efd,
136: int extusage, int nonblock);
1.22 markus 137:
138: void deny_input_open(int type, int plen, void *ctxt);
1.7 markus 139:
1.20 markus 140: void channel_input_channel_request(int type, int plen, void *ctxt);
141: void channel_input_close(int type, int plen, void *ctxt);
142: void channel_input_close_confirmation(int type, int plen, void *ctxt);
143: void channel_input_data(int type, int plen, void *ctxt);
144: void channel_input_extended_data(int type, int plen, void *ctxt);
145: void channel_input_ieof(int type, int plen, void *ctxt);
146: void channel_input_oclose(int type, int plen, void *ctxt);
147: void channel_input_open_confirmation(int type, int plen, void *ctxt);
148: void channel_input_open_failure(int type, int plen, void *ctxt);
149: void channel_input_port_open(int type, int plen, void *ctxt);
150: void channel_input_window_adjust(int type, int plen, void *ctxt);
1.7 markus 151:
152: /* Sets specific protocol options. */
153: void channel_set_options(int hostname_in_open);
154:
155: /*
156: * Allocate a new channel object and set its type and socket. Remote_name
157: * must have been allocated with xmalloc; this will free it when the channel
158: * is freed.
159: */
160: int channel_allocate(int type, int sock, char *remote_name);
161:
162: /* Free the channel and close its socket. */
163: void channel_free(int channel);
164:
165: /* Add any bits relevant to channels in select bitmasks. */
166: void channel_prepare_select(fd_set * readset, fd_set * writeset);
167:
168: /*
169: * After select, perform any appropriate operations for channels which have
170: * events pending.
171: */
172: void channel_after_select(fd_set * readset, fd_set * writeset);
173:
174: /* If there is data to send to the connection, send some of it now. */
175: void channel_output_poll(void);
176:
177: /* Returns true if no channel has too much buffered data. */
178: int channel_not_very_much_buffered_data(void);
179:
180: /* This closes any sockets that are listening for connections; this removes
181: any unix domain sockets. */
182: void channel_stop_listening(void);
183:
184: /*
185: * Closes the sockets of all channels. This is used to close extra file
186: * descriptors after a fork.
187: */
188: void channel_close_all(void);
189:
190: /* Returns the maximum file descriptor number used by the channels. */
191: int channel_max_fd(void);
192:
193: /* Returns true if there is still an open channel over the connection. */
194: int channel_still_open(void);
195:
196: /*
197: * Returns a string containing a list of all open channels. The list is
198: * suitable for displaying to the user. It uses crlf instead of newlines.
199: * The caller should free the string with xfree.
200: */
201: char *channel_open_message(void);
202:
203: /*
204: * Initiate forwarding of connections to local port "port" through the secure
1.23 ! markus 205: * channel to host:port from remote side.
1.7 markus 206: */
1.9 markus 207: void
1.23 ! markus 208: channel_request_local_forwarding(u_short listen_port,
! 209: const char *host_to_connect, u_short port_to_connect, int gateway_ports);
! 210: void
! 211: channel_request_forwarding(const char *listen_address, u_short listen_port,
! 212: const char *host_to_connect, u_short port_to_connect, int gateway_ports,
! 213: int remote_fwd);
1.7 markus 214:
215: /*
216: * Initiate forwarding of connections to port "port" on remote host through
217: * the secure channel to host:port from local side. This never returns if
218: * there was an error. This registers that open requests for that port are
219: * permitted.
220: */
1.9 markus 221: void
1.7 markus 222: channel_request_remote_forwarding(u_short port, const char *host,
223: u_short remote_port);
224:
225: /*
226: * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually
227: * called by the server, because the user could connect to any port anyway,
228: * and the server has no way to know but to trust the client anyway.
229: */
230: void channel_permit_all_opens(void);
231:
232: /*
233: * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
234: * listening for the port, and sends back a success reply (or disconnect
235: * message if there was an error). This never returns if there was an error.
236: */
1.12 markus 237: void channel_input_port_forward_request(int is_root, int gateway_ports);
1.7 markus 238:
239: /*
240: * Creates a port for X11 connections, and starts listening for it. Returns
241: * the display name, or NULL if an error was encountered.
242: */
243: char *x11_create_display(int screen);
244:
245: /*
246: * Creates an internet domain socket for listening for X11 connections.
247: * Returns a suitable value for the DISPLAY variable, or NULL if an error
248: * occurs.
249: */
250: char *x11_create_display_inet(int screen, int x11_display_offset);
251:
252: /*
253: * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
254: * the remote channel number. We should do whatever we want, and respond
255: * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
256: */
1.20 markus 257: void x11_input_open(int type, int plen, void *ctxt);
1.7 markus 258:
259: /*
260: * Requests forwarding of X11 connections. This should be called on the
261: * client only.
262: */
263: void x11_request_forwarding(void);
264:
265: /*
266: * Requests forwarding for X11 connections, with authentication spoofing.
267: * This should be called in the client only.
268: */
1.10 markus 269: void
270: x11_request_forwarding_with_spoofing(int client_session_id,
271: const char *proto, const char *data);
1.7 markus 272:
273: /* Sends a message to the server to request authentication fd forwarding. */
274: void auth_request_forwarding(void);
275:
276: /*
277: * Returns the name of the forwarded authentication socket. Returns NULL if
278: * there is no forwarded authentication socket. The returned value points to
279: * a static buffer.
280: */
281: char *auth_get_socket_name(void);
282:
283: /*
1.13 markus 284: * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
1.7 markus 285: * This starts forwarding authentication requests.
286: */
1.13 markus 287: int auth_input_request_forwarding(struct passwd * pw);
1.7 markus 288:
289: /* This is called to process an SSH_SMSG_AGENT_OPEN message. */
1.20 markus 290: void auth_input_open_request(int type, int plen, void *ctxt);
1.8 markus 291:
292: /* XXX */
293: int channel_connect_to(const char *host, u_short host_port);
1.23 ! markus 294: int channel_connect_by_listen_adress(u_short listen_port);
1.10 markus 295: int x11_connect_display(void);
1.7 markus 296:
1.1 markus 297: #endif
![[BACK]](/icons/back.gif){kind=icon}
Return to channels.h CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh