[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) 1999, 2000, 2001 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 1.40 2001/06/25 08:25:36 markus Exp $"); */

#ifndef CHANNEL_H
#define CHANNEL_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)

/* possible input states */
#define CHAN_INPUT_OPEN			0x01
#define CHAN_INPUT_WAIT_DRAIN		0x02
#define CHAN_INPUT_WAIT_OCLOSE		0x04
#define CHAN_INPUT_CLOSED		0x08

/* possible output states */
#define CHAN_OUTPUT_OPEN		0x10
#define CHAN_OUTPUT_WAIT_DRAIN		0x20
#define CHAN_OUTPUT_WAIT_IEOF		0x40
#define CHAN_OUTPUT_CLOSED		0x80

#define CHAN_CLOSE_SENT			0x01
#define CHAN_CLOSE_RCVD			0x02


/* channel management */

Channel	*channel_lookup(int id);
Channel *
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
    int window, int maxpack, int extusage, char *remote_name, int nonblock);
void
channel_set_fds(int id, int rfd, int wfd, int efd,
    int extusage, int nonblock);
void    channel_free(Channel *c);
void    channel_free_all(void);

void	channel_send_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);

/* protocol handler */

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);

/* file descriptor handling (read/write) */

void
channel_prepare_select(fd_set **readsetp, fd_set **writesetp, int *maxfdp,
    int rekeying);
void    channel_after_select(fd_set * readset, fd_set * writeset);
void    channel_output_poll(void);

int     channel_not_very_much_buffered_data(void);
void    channel_close_all(void);
void    channel_free_all(void);
int     channel_still_open(void);
char   *channel_open_message(void);
int	channel_find_open(void);

/* channel_tcpfwd.c */
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);
void
channel_request_remote_forwarding(u_short port, const char *host,
    u_short remote_port);
void    channel_permit_all_opens(void);
void	channel_add_permitted_opens(char *host, int port);
void	channel_clear_permitted_opens(void);
void    channel_input_port_forward_request(int is_root, int gateway_ports);
int	channel_connect_to(const char *host, u_short host_port);
int	channel_connect_by_listen_adress(u_short listen_port);

/* x11 forwarding */

int	x11_connect_display(void);
char   *x11_create_display(int screen);
char   *x11_create_display_inet(int screen, int x11_display_offset);
void    x11_input_open(int type, int plen, void *ctxt);
void    x11_request_forwarding(void);
void
x11_request_forwarding_with_spoofing(int client_session_id,
    const char *proto, const char *data);
void	deny_input_open(int type, int plen, void *ctxt);

/* agent forwarding */

void    auth_request_forwarding(void);
char   *auth_get_socket_name(void);
void	auth_sock_cleanup_proc(void *pw);
int     auth_input_request_forwarding(struct passwd * pw);
void    auth_input_open_request(int type, int plen, void *ctxt);

/* channel close */

typedef void    chan_event_fn(Channel * c);

/* for the input state */
extern chan_event_fn	*chan_rcvd_oclose;
extern chan_event_fn	*chan_read_failed;
extern chan_event_fn	*chan_ibuf_empty;

/* for the output state */
extern chan_event_fn	*chan_rcvd_ieof;
extern chan_event_fn	*chan_write_failed;
extern chan_event_fn	*chan_obuf_empty;

int	chan_is_dead(Channel * c);
void	chan_mark_dead(Channel * c);
void    chan_init_iostates(Channel * c);
void	chan_init(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	/*
a96070d4	13	* Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
bcbf86ec	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	*/
a96070d4	35	/* RCSID("$OpenBSD: channels.h,v 1.40 2001/06/25 08:25:36 markus Exp $"); */
8efc0c15	36
8e7895b8	37	#ifndef CHANNEL_H
8e7895b8	38	#define CHANNEL_H
8efc0c15	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
8e7895b8	127	/* possible input states */
	128	#define CHAN_INPUT_OPEN 0x01
	129	#define CHAN_INPUT_WAIT_DRAIN 0x02
	130	#define CHAN_INPUT_WAIT_OCLOSE 0x04
	131	#define CHAN_INPUT_CLOSED 0x08
bcbf86ec	132
8e7895b8	133	/* possible output states */
	134	#define CHAN_OUTPUT_OPEN 0x10
	135	#define CHAN_OUTPUT_WAIT_DRAIN 0x20
	136	#define CHAN_OUTPUT_WAIT_IEOF 0x40
	137	#define CHAN_OUTPUT_CLOSED 0x80
	138
	139	#define CHAN_CLOSE_SENT 0x01
	140	#define CHAN_CLOSE_RCVD 0x02
	141
	142
	143	/* channel management */
	144
	145	Channel *channel_lookup(int id);
	146	Channel *
	147	channel_new(char *ctype, int type, int rfd, int wfd, int efd,
	148	int window, int maxpack, int extusage, char *remote_name, int nonblock);
	149	void
	150	channel_set_fds(int id, int rfd, int wfd, int efd,
	151	int extusage, int nonblock);
	152	void channel_free(Channel *c);
d6746a0b	153	void channel_free_all(void);
8e7895b8	154
8e7895b8	155	void channel_send_open(int id);
7e7327a1	156	void channel_request(int id, char *service, int wantconfirm);
	157	void channel_request_start(int id, char *service, int wantconfirm);
	158	void channel_register_callback(int id, int mtype, channel_callback_fn fn, void arg);
	159	void channel_register_cleanup(int id, channel_callback_fn *fn);
2e73a022	160	void channel_register_filter(int id, channel_filter_fn *fn);
7e7327a1	161	void channel_cancel_cleanup(int id);
7368a6c8	162
8e7895b8	163	/* protocol handler */
7368a6c8	164
188adeb2	165	void channel_input_channel_request(int type, int plen, void *ctxt);
	166	void channel_input_close(int type, int plen, void *ctxt);
	167	void channel_input_close_confirmation(int type, int plen, void *ctxt);
	168	void channel_input_data(int type, int plen, void *ctxt);
	169	void channel_input_extended_data(int type, int plen, void *ctxt);
	170	void channel_input_ieof(int type, int plen, void *ctxt);
	171	void channel_input_oclose(int type, int plen, void *ctxt);
	172	void channel_input_open_confirmation(int type, int plen, void *ctxt);
	173	void channel_input_open_failure(int type, int plen, void *ctxt);
	174	void channel_input_port_open(int type, int plen, void *ctxt);
	175	void channel_input_window_adjust(int type, int plen, void *ctxt);
7368a6c8	176
8e7895b8	177	/* file descriptor handling (read/write) */
7368a6c8	178
39929cdb	179	void
c422989b	180	channel_prepare_select(fd_set readsetp, fd_set writesetp, int *maxfdp,
c422989b	181	int rekeying);
7368a6c8	182	void channel_after_select(fd_set * readset, fd_set * writeset);
7368a6c8	183	void channel_output_poll(void);
7368a6c8	184
7368a6c8	185	int channel_not_very_much_buffered_data(void);
7368a6c8	186	void channel_close_all(void);
d6746a0b	187	void channel_free_all(void);
7368a6c8	188	int channel_still_open(void);
7368a6c8	189	char *channel_open_message(void);
8e7895b8	190	int channel_find_open(void);
7368a6c8	191
8e7895b8	192	/* channel_tcpfwd.c */
02a024dd	193	int
fa08c86b	194	channel_request_local_forwarding(u_short listen_port,
fa08c86b	195	const char *host_to_connect, u_short port_to_connect, int gateway_ports);
02a024dd	196	int
fa08c86b	197	channel_request_forwarding(const char *listen_address, u_short listen_port,
	198	const char *host_to_connect, u_short port_to_connect, int gateway_ports,
	199	int remote_fwd);
6ae2364d	200	void
7368a6c8	201	channel_request_remote_forwarding(u_short port, const char *host,
7368a6c8	202	u_short remote_port);
7368a6c8	203	void channel_permit_all_opens(void);
01794848	204	void channel_add_permitted_opens(char *host, int port);
01794848	205	void channel_clear_permitted_opens(void);
1d1ffb87	206	void channel_input_port_forward_request(int is_root, int gateway_ports);
8e7895b8	207	int channel_connect_to(const char *host, u_short host_port);
8e7895b8	208	int channel_connect_by_listen_adress(u_short listen_port);
7368a6c8	209
8e7895b8	210	/* x11 forwarding */
7368a6c8	211
8e7895b8	212	int x11_connect_display(void);
8e7895b8	213	char *x11_create_display(int screen);
7368a6c8	214	char *x11_create_display_inet(int screen, int x11_display_offset);
188adeb2	215	void x11_input_open(int type, int plen, void *ctxt);
7368a6c8	216	void x11_request_forwarding(void);
0b242b12	217	void
	218	x11_request_forwarding_with_spoofing(int client_session_id,
	219	const char proto, const char data);
8e7895b8	220	void deny_input_open(int type, int plen, void *ctxt);
7368a6c8	221
8e7895b8	222	/* agent forwarding */
7368a6c8	223
8e7895b8	224	void auth_request_forwarding(void);
7368a6c8	225	char *auth_get_socket_name(void);
f0f32b8e	226	void auth_sock_cleanup_proc(void *pw);
fa649821	227	int auth_input_request_forwarding(struct passwd * pw);
188adeb2	228	void auth_input_open_request(int type, int plen, void *ctxt);
7368a6c8	229
8e7895b8	230	/* channel close */
7e7327a1	231
8e7895b8	232	typedef void chan_event_fn(Channel * c);
	233
	234	/* for the input state */
	235	extern chan_event_fn *chan_rcvd_oclose;
	236	extern chan_event_fn *chan_read_failed;
	237	extern chan_event_fn *chan_ibuf_empty;
	238
	239	/* for the output state */
	240	extern chan_event_fn *chan_rcvd_ieof;
	241	extern chan_event_fn *chan_write_failed;
	242	extern chan_event_fn *chan_obuf_empty;
	243
	244	int chan_is_dead(Channel * c);
	245	void chan_mark_dead(Channel * c);
	246	void chan_init_iostates(Channel * c);
	247	void chan_init(void);
3ffc6336	248
8efc0c15	249	#endif