[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 1.33 2001/05/28 23:14:49 markus Exp $"); */

#ifndef CHANNELS_H
#define CHANNELS_H

#include "buffer.h"

/* Definitions for channel types. */
#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_DYNAMIC		13
#define SSH_CHANNEL_ZOMBIE		14	/* Almost dead. */
#define SSH_CHANNEL_MAX_TYPE		15

#define SSH_CHANNEL_PATH_LEN		30

/*
 * Data structure for channel data.  This is initialized in channel_new
 * 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[SSH_CHANNEL_PATH_LEN];
		/* 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);

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.
 */
Channel *
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
    int window, int maxpack, int extended_usage, char *remote_name,
    int nonblock);

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

/*
 * 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,
    int rekeying);

/*
 * 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);

int	channel_find_open(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	*/
6fd8622b	35	/* RCSID("$OpenBSD: channels.h,v 1.33 2001/05/28 23:14:49 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_X11_LISTENER 1 /* Listening for inet X11 conn. */
5260325f	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 */
aa3378df	47	#define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
7368a6c8	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 */
fa08c86b	53	#define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
97fb6912	54	#define SSH_CHANNEL_CONNECTING 12
0490e609	55	#define SSH_CHANNEL_DYNAMIC 13
6fd8622b	56	#define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
6fd8622b	57	#define SSH_CHANNEL_MAX_TYPE 15
8efc0c15	58
719fc62f	59	#define SSH_CHANNEL_PATH_LEN 30
719fc62f	60
aa3378df	61	/*
719fc62f	62	* Data structure for channel data. This is initialized in channel_new
aa3378df	63	* and cleared in channel_free.
aa3378df	64	*/
2e73a022	65	struct Channel;
	66	typedef struct Channel Channel;
	67
7368a6c8	68	typedef void channel_callback_fn(int id, void *arg);
2e73a022	69	typedef int channel_filter_fn(struct Channel c, char buf, int len);
8efc0c15	70
2e73a022	71	struct Channel {
5260325f	72	int type; /* channel type/state */
	73	int self; /* my own channel identifier */
	74	int remote_id; /* channel identifier for remote peer */
	75	/* peer can be reached over encrypted connection, via packet-sent */
	76	int istate; /* input from channel (state of receive half) */
	77	int ostate; /* output to channel (state of transmit half) */
7e7327a1	78	int flags; /* close sent/rcvd */
7368a6c8	79	int rfd; /* read fd */
	80	int wfd; /* write fd */
	81	int efd; /* extended fd */
	82	int sock; /* sock fd */
0ae4fe1d	83	int isatty; /* rfd is a tty */
5260325f	84	Buffer input; /* data read from socket, to be sent over
	85	* encrypted connection */
	86	Buffer output; /* data received over encrypted connection for
	87	* send on socket */
7368a6c8	88	Buffer extended;
719fc62f	89	char path[SSH_CHANNEL_PATH_LEN];
719fc62f	90	/* path for unix domain sockets, or host name for forwards */
5260325f	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 */
7368a6c8	94
	95	int remote_window;
	96	int remote_maxpacket;
	97	int local_window;
	98	int local_window_max;
	99	int local_consumed;
	100	int local_maxpacket;
	101	int extended_usage;
	102
	103	char ctype; / type */
	104
1d1ffb87	105	/* callback */
7368a6c8	106	channel_callback_fn *cb_fn;
	107	void *cb_arg;
	108	int cb_event;
	109	channel_callback_fn *dettach_user;
2e73a022	110
	111	/* filter */
	112	channel_filter_fn *input_filter;
	113	};
7368a6c8	114
	115	#define CHAN_EXTENDED_IGNORE 0
	116	#define CHAN_EXTENDED_READ 1
	117	#define CHAN_EXTENDED_WRITE 2
	118
bcbf86ec	119	/* default window/packet sizes for tcp/x11-fwd-channel */
	120	#define CHAN_SES_WINDOW_DEFAULT (32*1024)
	121	#define CHAN_SES_PACKET_DEFAULT (CHAN_SES_WINDOW_DEFAULT/2)
	122	#define CHAN_TCP_WINDOW_DEFAULT (32*1024)
	123	#define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2)
	124	#define CHAN_X11_WINDOW_DEFAULT (4*1024)
	125	#define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2)
	126
	127
7368a6c8	128	void channel_open(int id);
7e7327a1	129	void channel_request(int id, char *service, int wantconfirm);
	130	void channel_request_start(int id, char *service, int wantconfirm);
	131	void channel_register_callback(int id, int mtype, channel_callback_fn fn, void arg);
	132	void channel_register_cleanup(int id, channel_callback_fn *fn);
2e73a022	133	void channel_register_filter(int id, channel_filter_fn *fn);
7e7327a1	134	void channel_cancel_cleanup(int id);
7368a6c8	135	Channel *channel_lookup(int id);
7368a6c8	136
a22aff1f	137	void
	138	channel_set_fds(int id, int rfd, int wfd, int efd,
	139	int extusage, int nonblock);
	140
	141	void deny_input_open(int type, int plen, void *ctxt);
7368a6c8	142
188adeb2	143	void channel_input_channel_request(int type, int plen, void *ctxt);
	144	void channel_input_close(int type, int plen, void *ctxt);
	145	void channel_input_close_confirmation(int type, int plen, void *ctxt);
	146	void channel_input_data(int type, int plen, void *ctxt);
	147	void channel_input_extended_data(int type, int plen, void *ctxt);
	148	void channel_input_ieof(int type, int plen, void *ctxt);
	149	void channel_input_oclose(int type, int plen, void *ctxt);
	150	void channel_input_open_confirmation(int type, int plen, void *ctxt);
	151	void channel_input_open_failure(int type, int plen, void *ctxt);
	152	void channel_input_port_open(int type, int plen, void *ctxt);
	153	void channel_input_window_adjust(int type, int plen, void *ctxt);
7368a6c8	154
	155	/* Sets specific protocol options. */
	156	void channel_set_options(int hostname_in_open);
	157
	158	/*
	159	* Allocate a new channel object and set its type and socket. Remote_name
	160	* must have been allocated with xmalloc; this will free it when the channel
	161	* is freed.
	162	*/
719fc62f	163	Channel *
	164	channel_new(char *ctype, int type, int rfd, int wfd, int efd,
	165	int window, int maxpack, int extended_usage, char *remote_name,
	166	int nonblock);
7368a6c8	167
7368a6c8	168	/* Free the channel and close its socket. */
719fc62f	169	void channel_free(Channel *c);
7368a6c8	170
39929cdb	171	/*
	172	* Allocate/update select bitmasks and add any bits relevant to channels in
	173	* select bitmasks.
	174	*/
	175	void
c422989b	176	channel_prepare_select(fd_set readsetp, fd_set writesetp, int *maxfdp,
c422989b	177	int rekeying);
7368a6c8	178
	179	/*
	180	* After select, perform any appropriate operations for channels which have
	181	* events pending.
	182	*/
	183	void channel_after_select(fd_set * readset, fd_set * writeset);
	184
	185	/* If there is data to send to the connection, send some of it now. */
	186	void channel_output_poll(void);
	187
	188	/* Returns true if no channel has too much buffered data. */
	189	int channel_not_very_much_buffered_data(void);
	190
	191	/* This closes any sockets that are listening for connections; this removes
	192	any unix domain sockets. */
	193	void channel_stop_listening(void);
	194
	195	/*
	196	* Closes the sockets of all channels. This is used to close extra file
	197	* descriptors after a fork.
	198	*/
	199	void channel_close_all(void);
	200
7368a6c8	201	/* Returns true if there is still an open channel over the connection. */
	202	int channel_still_open(void);
	203
	204	/*
	205	* Returns a string containing a list of all open channels. The list is
	206	* suitable for displaying to the user. It uses crlf instead of newlines.
	207	* The caller should free the string with xfree.
	208	*/
	209	char *channel_open_message(void);
	210
	211	/*
	212	* Initiate forwarding of connections to local port "port" through the secure
fa08c86b	213	* channel to host:port from remote side.
7368a6c8	214	*/
02a024dd	215	int
fa08c86b	216	channel_request_local_forwarding(u_short listen_port,
fa08c86b	217	const char *host_to_connect, u_short port_to_connect, int gateway_ports);
02a024dd	218	int
fa08c86b	219	channel_request_forwarding(const char *listen_address, u_short listen_port,
	220	const char *host_to_connect, u_short port_to_connect, int gateway_ports,
	221	int remote_fwd);
7368a6c8	222
	223	/*
	224	* Initiate forwarding of connections to port "port" on remote host through
	225	* the secure channel to host:port from local side. This never returns if
	226	* there was an error. This registers that open requests for that port are
	227	* permitted.
	228	*/
6ae2364d	229	void
7368a6c8	230	channel_request_remote_forwarding(u_short port, const char *host,
	231	u_short remote_port);
	232
	233	/*
01794848	234	* Permits opening to any host/port if permitted_opens[] is empty. This is
	235	* usually called by the server, because the user could connect to any port
	236	* anyway, and the server has no way to know but to trust the client anyway.
7368a6c8	237	*/
	238	void channel_permit_all_opens(void);
	239
01794848	240	/* Add host/port to list of allowed targets for port forwarding */
	241	void channel_add_permitted_opens(char *host, int port);
	242
	243	/* Flush list */
	244	void channel_clear_permitted_opens(void);
	245
7368a6c8	246	/*
	247	* This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
	248	* listening for the port, and sends back a success reply (or disconnect
	249	* message if there was an error). This never returns if there was an error.
	250	*/
1d1ffb87	251	void channel_input_port_forward_request(int is_root, int gateway_ports);
7368a6c8	252
	253	/*
	254	* Creates a port for X11 connections, and starts listening for it. Returns
	255	* the display name, or NULL if an error was encountered.
	256	*/
	257	char *x11_create_display(int screen);
	258
	259	/*
	260	* Creates an internet domain socket for listening for X11 connections.
	261	* Returns a suitable value for the DISPLAY variable, or NULL if an error
	262	* occurs.
	263	*/
	264	char *x11_create_display_inet(int screen, int x11_display_offset);
	265
	266	/*
	267	* This is called when SSH_SMSG_X11_OPEN is received. The packet contains
	268	* the remote channel number. We should do whatever we want, and respond
	269	* with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
	270	*/
188adeb2	271	void x11_input_open(int type, int plen, void *ctxt);
7368a6c8	272
	273	/*
	274	* Requests forwarding of X11 connections. This should be called on the
	275	* client only.
	276	*/
	277	void x11_request_forwarding(void);
	278
	279	/*
	280	* Requests forwarding for X11 connections, with authentication spoofing.
	281	* This should be called in the client only.
	282	*/
0b242b12	283	void
	284	x11_request_forwarding_with_spoofing(int client_session_id,
	285	const char proto, const char data);
7368a6c8	286
	287	/* Sends a message to the server to request authentication fd forwarding. */
	288	void auth_request_forwarding(void);
	289
	290	/*
	291	* Returns the name of the forwarded authentication socket. Returns NULL if
	292	* there is no forwarded authentication socket. The returned value points to
	293	* a static buffer.
	294	*/
	295	char *auth_get_socket_name(void);
	296
	297	/*
fa649821	298	* This is called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
7368a6c8	299	* This starts forwarding authentication requests.
7368a6c8	300	*/
fa649821	301	int auth_input_request_forwarding(struct passwd * pw);
7368a6c8	302
7368a6c8	303	/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
188adeb2	304	void auth_input_open_request(int type, int plen, void *ctxt);
7368a6c8	305
7e7327a1	306	/* XXX */
7e7327a1	307	int channel_connect_to(const char *host, u_short host_port);
fa08c86b	308	int channel_connect_by_listen_adress(u_short listen_port);
0b242b12	309	int x11_connect_display(void);
7e7327a1	310
3ffc6336	311	int channel_find_open(void);
3ffc6336	312
8efc0c15	313	#endif