[openssh.git] / channels.h

/*
 * Author: Tatu Ylonen <ylo@cs.hut.fi>
 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
 *                    All rights reserved
 *
 * As far as I am concerned, the code I have written for this software
 * can be used freely for any purpose.  Any derived versions of this
 * software must be clearly marked as such, and if the derived work is
 * incompatible with the protocol description in the RFC file, it must be
 * called by a name other than "ssh" or "Secure Shell".
 */
/*
 * Copyright (c) 2000 Markus Friedl.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
/* RCSID("$OpenBSD: channels.h,v 1.28 2001/03/16 19:06:29 markus Exp $"); */

#ifndef CHANNELS_H
#define CHANNELS_H

#include "buffer.h"

/* Definitions for channel types. */
#define SSH_CHANNEL_FREE		0	/* This channel is free (unused). */
#define SSH_CHANNEL_X11_LISTENER	1	/* Listening for inet X11 conn. */
#define SSH_CHANNEL_PORT_LISTENER	2	/* Listening on a port. */
#define SSH_CHANNEL_OPENING		3	/* waiting for confirmation */
#define SSH_CHANNEL_OPEN		4	/* normal open two-way channel */
#define SSH_CHANNEL_CLOSED		5	/* waiting for close confirmation */
#define SSH_CHANNEL_AUTH_SOCKET		6	/* authentication socket */
#define SSH_CHANNEL_X11_OPEN		7	/* reading first X11 packet */
#define SSH_CHANNEL_INPUT_DRAINING	8	/* sending remaining data to conn */
#define SSH_CHANNEL_OUTPUT_DRAINING	9	/* sending remaining data to app */
#define SSH_CHANNEL_LARVAL		10	/* larval session */
#define SSH_CHANNEL_RPORT_LISTENER	11	/* Listening to a R-style port  */
#define SSH_CHANNEL_CONNECTING		12
#define SSH_CHANNEL_MAX_TYPE		13

/*
 * Data structure for channel data.  This is iniailized in channel_allocate
 * and cleared in channel_free.
 */
struct Channel;
typedef struct Channel Channel;

typedef void channel_callback_fn(int id, void *arg);
typedef int channel_filter_fn(struct Channel *c, char *buf, int len);

struct Channel {
	int     type;		/* channel type/state */
	int     self;		/* my own channel identifier */
	int     remote_id;	/* channel identifier for remote peer */
	/* peer can be reached over encrypted connection, via packet-sent */
	int     istate;		/* input from channel (state of receive half) */
	int     ostate;		/* output to channel  (state of transmit half) */
	int     flags;		/* close sent/rcvd */
	int     rfd;		/* read fd */
	int     wfd;		/* write fd */
	int     efd;		/* extended fd */
	int     sock;		/* sock fd */
	int     isatty;		/* rfd is a tty */
	Buffer  input;		/* data read from socket, to be sent over
				 * encrypted connection */
	Buffer  output;		/* data received over encrypted connection for
				 * send on socket */
	Buffer  extended;
	char    path[200];	/* path for unix domain sockets, or host name
				 * for forwards */
	int     listening_port;	/* port being listened for forwards */
	int     host_port;	/* remote port to connect for forwards */
	char   *remote_name;	/* remote hostname */

	int	remote_window;
	int	remote_maxpacket;
	int	local_window;
	int	local_window_max;
	int	local_consumed;
	int	local_maxpacket;
	int     extended_usage;

	char   *ctype;		/* type */

	/* callback */
	channel_callback_fn	*cb_fn;
	void	*cb_arg;
	int	cb_event;
	channel_callback_fn	*dettach_user;

	/* filter */
	channel_filter_fn	*input_filter;
};

#define CHAN_EXTENDED_IGNORE		0
#define CHAN_EXTENDED_READ		1
#define CHAN_EXTENDED_WRITE		2

/* default window/packet sizes for tcp/x11-fwd-channel */
#define CHAN_SES_WINDOW_DEFAULT	(32*1024)
#define CHAN_SES_PACKET_DEFAULT	(CHAN_SES_WINDOW_DEFAULT/2)
#define CHAN_TCP_WINDOW_DEFAULT	(32*1024)
#define CHAN_TCP_PACKET_DEFAULT	(CHAN_TCP_WINDOW_DEFAULT/2)
#define CHAN_X11_WINDOW_DEFAULT	(4*1024)
#define CHAN_X11_PACKET_DEFAULT	(CHAN_X11_WINDOW_DEFAULT/2)


void	channel_open(int id);
void	channel_request(int id, char *service, int wantconfirm);
void	channel_request_start(int id, char *service, int wantconfirm);
void	channel_register_callback(int id, int mtype, channel_callback_fn *fn, void *arg);
void	channel_register_cleanup(int id, channel_callback_fn *fn);
void	channel_register_filter(int id, channel_filter_fn *fn);
void	channel_cancel_cleanup(int id);
Channel	*channel_lookup(int id);

int
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
    int window, int maxpack, int extended_usage, char *remote_name,
    int nonblock);
void
channel_set_fds(int id, int rfd, int wfd, int efd,
    int extusage, int nonblock);

void	deny_input_open(int type, int plen, void *ctxt);

void	channel_input_channel_request(int type, int plen, void *ctxt);
void	channel_input_close(int type, int plen, void *ctxt);
void	channel_input_close_confirmation(int type, int plen, void *ctxt);
void	channel_input_data(int type, int plen, void *ctxt);
void	channel_input_extended_data(int type, int plen, void *ctxt);
void	channel_input_ieof(int type, int plen, void *ctxt);
void	channel_input_oclose(int type, int plen, void *ctxt);
void	channel_input_open_confirmation(int type, int plen, void *ctxt);
void	channel_input_open_failure(int type, int plen, void *ctxt);
void	channel_input_port_open(int type, int plen, void *ctxt);
void	channel_input_window_adjust(int type, int plen, void *ctxt);

/* Sets specific protocol options. */
void    channel_set_options(int hostname_in_open);

/*
 * Allocate a new channel object and set its type and socket.  Remote_name
 * must have been allocated with xmalloc; this will free it when the channel
 * is freed.
 */
int     channel_allocate(int type, int sock, char *remote_name);

/* Free the channel and close its socket. */
void    channel_free(int channel);

/*
 * Allocate/update select bitmasks and add any bits relevant to channels in
 * select bitmasks.
 */
void
channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp);

/*
 * After select, perform any appropriate operations for channels which have
 * events pending.
 */
void    channel_after_select(fd_set * readset, fd_set * writeset);

/* If there is data to send to the connection, send some of it now. */
void    channel_output_poll(void);

/* Returns true if no channel has too much buffered data. */
int     channel_not_very_much_buffered_data(void);

/* This closes any sockets that are listening for connections; this removes
   any unix domain sockets. */
void    channel_stop_listening(void);

/*
 * Closes the sockets of all channels.  This is used to close extra file
 * descriptors after a fork.
 */
void    channel_close_all(void);

/* Returns true if there is still an open channel over the connection. */
int     channel_still_open(void);

/*
 * Returns a string containing a list of all open channels.  The list is
 * suitable for displaying to the user.  It uses crlf instead of newlines.
 * The caller should free the string with xfree.
 */
char   *channel_open_message(void);

/*
 * Initiate forwarding of connections to local port "port" through the secure
 * channel to host:port from remote side.
 */
int
channel_request_local_forwarding(u_short listen_port,
    const char *host_to_connect, u_short port_to_connect, int gateway_ports);
int
channel_request_forwarding(const char *listen_address, u_short listen_port,
    const char *host_to_connect, u_short port_to_connect, int gateway_ports,
    int remote_fwd);

/*
 * Initiate forwarding of connections to port "port" on remote host through
 * the secure channel to host:port from local side.  This never returns if
 * there was an error.  This registers that open requests for that port are
 * permitted.
 */
void
channel_request_remote_forwarding(u_short port, const char *host,
    u_short remote_port);

/*
 * Permits opening to any host/port if permitted_opens[] is empty.  This is
 * usually called by the server, because the user could connect to any port
 * anyway, and the server has no way to know but to trust the client anyway.
 */
void    channel_permit_all_opens(void);

/* Add host/port to list of allowed targets for port forwarding */
void	channel_add_permitted_opens(char *host, int port);

/* Flush list */
void	channel_clear_permitted_opens(void);

/*
 * This is called after receiving CHANNEL_FORWARDING_REQUEST.  This initates
 * listening for the port, and sends back a success reply (or disconnect
 * message if there was an error).  This never returns if there was an error.
 */
void    channel_input_port_forward_request(int is_root, int gateway_ports);

/*
 * Creates a port for X11 connections, and starts listening for it. Returns
 * the display name, or NULL if an error was encountered.
 */
char   *x11_create_display(int screen);

/*
 * Creates an internet domain socket for listening for X11 connections.
 * Returns a suitable value for the DISPLAY variable, or NULL if an error
 * occurs.
 */
char   *x11_create_display_inet(int screen, int x11_display_offset);

/*
 * This is called when SSH_SMSG_X11_OPEN is received.  The packet contains
 * the remote channel number.  We should do whatever we want, and respond
 * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
 */
void    x11_input_open(int type, int plen, void *ctxt);

/*
 * Requests forwarding of X11 connections.  This should be called on the
 * client only.
 */
void    x11_request_forwarding(void);

/*
 * Requests forwarding for X11 connections, with authentication spoofing.
 * This should be called in the client only.
 */
void
x11_request_forwarding_with_spoofing(int client_session_id,
    const char *proto, const char *data);

/* Sends a message to the server to request authentication fd forwarding. */
void    auth_request_forwarding(void);

/*
 * Returns the name of the forwarded authentication socket.  Returns NULL if
 * there is no forwarded authentication socket.  The returned value points to
 * a static buffer.
 */
char   *auth_get_socket_name(void);

/*
 * This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
 * This starts forwarding authentication requests.
 */
int     auth_input_request_forwarding(struct passwd * pw);

/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
void    auth_input_open_request(int type, int plen, void *ctxt);

/* XXX */
int	channel_connect_to(const char *host, u_short host_port);
int	channel_connect_by_listen_adress(u_short listen_port);
int	x11_connect_display(void);

#endif
Commit	Line	Data
bcbf86ec	1	/*
	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	/*
	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	*/
01794848	35	/* RCSID("$OpenBSD: channels.h,v 1.28 2001/03/16 19:06:29 markus Exp $"); */
8efc0c15	36
	37	#ifndef CHANNELS_H
	38	#define CHANNELS_H
	39
01794848	40	#include "buffer.h"
01794848	41
8efc0c15	42	/* Definitions for channel types. */
aa3378df	43	#define SSH_CHANNEL_FREE 0 /* This channel is free (unused). */
aa3378df	44	#define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
5260325f	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 */
aa3378df	48	#define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
7368a6c8	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 */
fa08c86b	54	#define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
97fb6912	55	#define SSH_CHANNEL_CONNECTING 12
97fb6912	56	#define SSH_CHANNEL_MAX_TYPE 13
8efc0c15	57
aa3378df	58	/*
	59	* Data structure for channel data. This is iniailized in channel_allocate
	60	* and cleared in channel_free.
	61	*/
2e73a022	62	struct Channel;
	63	typedef struct Channel Channel;
	64
7368a6c8	65	typedef void channel_callback_fn(int id, void *arg);
2e73a022	66	typedef int channel_filter_fn(struct Channel c, char buf, int len);
8efc0c15	67
2e73a022	68	struct Channel {
5260325f	69	int type; /* channel type/state */
	70	int self; /* my own channel identifier */
	71	int remote_id; /* channel identifier for remote peer */
	72	/* peer can be reached over encrypted connection, via packet-sent */
	73	int istate; /* input from channel (state of receive half) */
	74	int ostate; /* output to channel (state of transmit half) */
7e7327a1	75	int flags; /* close sent/rcvd */
7368a6c8	76	int rfd; /* read fd */
	77	int wfd; /* write fd */
	78	int efd; /* extended fd */
	79	int sock; /* sock fd */
0ae4fe1d	80	int isatty; /* rfd is a tty */
5260325f	81	Buffer input; /* data read from socket, to be sent over
	82	* encrypted connection */
	83	Buffer output; /* data received over encrypted connection for
	84	* send on socket */
7368a6c8	85	Buffer extended;
5260325f	86	char path[200]; /* path for unix domain sockets, or host name
	87	* 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 */
7368a6c8	91
	92	int remote_window;
	93	int remote_maxpacket;
	94	int local_window;
	95	int local_window_max;
	96	int local_consumed;
	97	int local_maxpacket;
	98	int extended_usage;
	99
	100	char ctype; / type */
	101
1d1ffb87	102	/* callback */
7368a6c8	103	channel_callback_fn *cb_fn;
	104	void *cb_arg;
	105	int cb_event;
	106	channel_callback_fn *dettach_user;
2e73a022	107
	108	/* filter */
	109	channel_filter_fn *input_filter;
	110	};
7368a6c8	111
	112	#define CHAN_EXTENDED_IGNORE 0
	113	#define CHAN_EXTENDED_READ 1
	114	#define CHAN_EXTENDED_WRITE 2
	115
bcbf86ec	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)
	123
	124
7368a6c8	125	void channel_open(int id);
7e7327a1	126	void channel_request(int id, char *service, int wantconfirm);
	127	void channel_request_start(int id, char *service, int wantconfirm);
	128	void channel_register_callback(int id, int mtype, channel_callback_fn fn, void arg);
	129	void channel_register_cleanup(int id, channel_callback_fn *fn);
2e73a022	130	void channel_register_filter(int id, channel_filter_fn *fn);
7e7327a1	131	void channel_cancel_cleanup(int id);
7368a6c8	132	Channel *channel_lookup(int id);
	133
	134	int
	135	channel_new(char *ctype, int type, int rfd, int wfd, int efd,
a22aff1f	136	int window, int maxpack, int extended_usage, char *remote_name,
	137	int nonblock);
	138	void
	139	channel_set_fds(int id, int rfd, int wfd, int efd,
	140	int extusage, int nonblock);
	141
	142	void deny_input_open(int type, int plen, void *ctxt);
7368a6c8	143
188adeb2	144	void channel_input_channel_request(int type, int plen, void *ctxt);
	145	void channel_input_close(int type, int plen, void *ctxt);
	146	void channel_input_close_confirmation(int type, int plen, void *ctxt);
	147	void channel_input_data(int type, int plen, void *ctxt);
	148	void channel_input_extended_data(int type, int plen, void *ctxt);
	149	void channel_input_ieof(int type, int plen, void *ctxt);
	150	void channel_input_oclose(int type, int plen, void *ctxt);
	151	void channel_input_open_confirmation(int type, int plen, void *ctxt);
	152	void channel_input_open_failure(int type, int plen, void *ctxt);
	153	void channel_input_port_open(int type, int plen, void *ctxt);
	154	void channel_input_window_adjust(int type, int plen, void *ctxt);
7368a6c8	155
	156	/* Sets specific protocol options. */
	157	void channel_set_options(int hostname_in_open);
	158
	159	/*
	160	* Allocate a new channel object and set its type and socket. Remote_name
	161	* must have been allocated with xmalloc; this will free it when the channel
	162	* is freed.
	163	*/
	164	int channel_allocate(int type, int sock, char *remote_name);
	165
	166	/* Free the channel and close its socket. */
	167	void channel_free(int channel);
	168
39929cdb	169	/*
	170	* Allocate/update select bitmasks and add any bits relevant to channels in
	171	* select bitmasks.
	172	*/
	173	void
	174	channel_prepare_select(fd_set readsetp, fd_set writesetp, int *maxfdp);
7368a6c8	175
	176	/*
	177	* After select, perform any appropriate operations for channels which have
	178	* events pending.
	179	*/
	180	void channel_after_select(fd_set * readset, fd_set * writeset);
	181
	182	/* If there is data to send to the connection, send some of it now. */
	183	void channel_output_poll(void);
	184
	185	/* Returns true if no channel has too much buffered data. */
	186	int channel_not_very_much_buffered_data(void);
	187
	188	/* This closes any sockets that are listening for connections; this removes
	189	any unix domain sockets. */
	190	void channel_stop_listening(void);
	191
	192	/*
	193	* Closes the sockets of all channels. This is used to close extra file
	194	* descriptors after a fork.
	195	*/
	196	void channel_close_all(void);
	197
7368a6c8	198	/* Returns true if there is still an open channel over the connection. */
	199	int channel_still_open(void);
	200
	201	/*
	202	* Returns a string containing a list of all open channels. The list is
	203	* suitable for displaying to the user. It uses crlf instead of newlines.
	204	* The caller should free the string with xfree.
	205	*/
	206	char *channel_open_message(void);
	207
	208	/*
	209	* Initiate forwarding of connections to local port "port" through the secure
fa08c86b	210	* channel to host:port from remote side.
7368a6c8	211	*/
02a024dd	212	int
fa08c86b	213	channel_request_local_forwarding(u_short listen_port,
fa08c86b	214	const char *host_to_connect, u_short port_to_connect, int gateway_ports);
02a024dd	215	int
fa08c86b	216	channel_request_forwarding(const char *listen_address, u_short listen_port,
	217	const char *host_to_connect, u_short port_to_connect, int gateway_ports,
	218	int remote_fwd);
7368a6c8	219
	220	/*
	221	* Initiate forwarding of connections to port "port" on remote host through
	222	* the secure channel to host:port from local side. This never returns if
	223	* there was an error. This registers that open requests for that port are
	224	* permitted.
	225	*/
6ae2364d	226	void
7368a6c8	227	channel_request_remote_forwarding(u_short port, const char *host,
	228	u_short remote_port);
	229
	230	/*
01794848	231	* Permits opening to any host/port if permitted_opens[] is empty. This is
	232	* usually called by the server, because the user could connect to any port
	233	* anyway, and the server has no way to know but to trust the client anyway.
7368a6c8	234	*/
	235	void channel_permit_all_opens(void);
	236
01794848	237	/* Add host/port to list of allowed targets for port forwarding */
	238	void channel_add_permitted_opens(char *host, int port);
	239
	240	/* Flush list */
	241	void channel_clear_permitted_opens(void);
	242
7368a6c8	243	/*
	244	* This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
	245	* listening for the port, and sends back a success reply (or disconnect
	246	* message if there was an error). This never returns if there was an error.
	247	*/
1d1ffb87	248	void channel_input_port_forward_request(int is_root, int gateway_ports);
7368a6c8	249
	250	/*
	251	* Creates a port for X11 connections, and starts listening for it. Returns
	252	* the display name, or NULL if an error was encountered.
	253	*/
	254	char *x11_create_display(int screen);
	255
	256	/*
	257	* Creates an internet domain socket for listening for X11 connections.
	258	* Returns a suitable value for the DISPLAY variable, or NULL if an error
	259	* occurs.
	260	*/
	261	char *x11_create_display_inet(int screen, int x11_display_offset);
	262
	263	/*
	264	* This is called when SSH_SMSG_X11_OPEN is received. The packet contains
	265	* the remote channel number. We should do whatever we want, and respond
	266	* with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
	267	*/
188adeb2	268	void x11_input_open(int type, int plen, void *ctxt);
7368a6c8	269
	270	/*
	271	* Requests forwarding of X11 connections. This should be called on the
	272	* client only.
	273	*/
	274	void x11_request_forwarding(void);
	275
	276	/*
	277	* Requests forwarding for X11 connections, with authentication spoofing.
	278	* This should be called in the client only.
	279	*/
0b242b12	280	void
	281	x11_request_forwarding_with_spoofing(int client_session_id,
	282	const char proto, const char data);
7368a6c8	283
	284	/* Sends a message to the server to request authentication fd forwarding. */
	285	void auth_request_forwarding(void);
	286
	287	/*
	288	* Returns the name of the forwarded authentication socket. Returns NULL if
	289	* there is no forwarded authentication socket. The returned value points to
	290	* a static buffer.
	291	*/
	292	char *auth_get_socket_name(void);
	293
	294	/*
fa649821	295	* This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
7368a6c8	296	* This starts forwarding authentication requests.
7368a6c8	297	*/
fa649821	298	int auth_input_request_forwarding(struct passwd * pw);
7368a6c8	299
7368a6c8	300	/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
188adeb2	301	void auth_input_open_request(int type, int plen, void *ctxt);
7368a6c8	302
7e7327a1	303	/* XXX */
7e7327a1	304	int channel_connect_to(const char *host, u_short host_port);
fa08c86b	305	int channel_connect_by_listen_adress(u_short listen_port);
0b242b12	306	int x11_connect_display(void);
7e7327a1	307
8efc0c15	308	#endif