[openssh.git] / channels.h

/*	$OpenBSD: channels.h,v 1.75 2004/10/29 21:47:15 djm Exp $	*/

/*
 * 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, 2002 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.
 */

#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		256

struct Channel;
typedef struct Channel Channel;

typedef void channel_callback_fn(int, void *);
typedef int channel_filter_fn(struct Channel *, char *, int);

struct Channel {
	int     type;		/* channel type/state */
	int     self;		/* my own channel identifier */
	int     remote_id;	/* channel identifier for remote peer */
	u_int   istate;		/* input from channel (state of receive half) */
	u_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     ctl_fd;		/* control fd (client sharing) */
	int     isatty;		/* rfd is a tty */
	int     wfd_isatty;	/* wfd is a tty */
	int	client_tty;	/* (client) TTY has been requested */
	int     force_drain;	/* force close on iEOF */
	int     delayed;		/* fdset hack */
	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 */

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

	char   *ctype;		/* type */

	/* callback */
	channel_callback_fn	*confirm;
	channel_callback_fn	*detach_user;
	void			*confirm_ctx;

	/* 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_PACKET_DEFAULT	(32*1024)
#define CHAN_SES_WINDOW_DEFAULT	(4*CHAN_SES_PACKET_DEFAULT)
#define CHAN_TCP_PACKET_DEFAULT	(32*1024)
#define CHAN_TCP_WINDOW_DEFAULT	(4*CHAN_TCP_PACKET_DEFAULT)
#define CHAN_X11_PACKET_DEFAULT	(16*1024)
#define CHAN_X11_WINDOW_DEFAULT	(4*CHAN_X11_PACKET_DEFAULT)

/* possible input states */
#define CHAN_INPUT_OPEN			0
#define CHAN_INPUT_WAIT_DRAIN		1
#define CHAN_INPUT_WAIT_OCLOSE		2
#define CHAN_INPUT_CLOSED		3

/* possible output states */
#define CHAN_OUTPUT_OPEN		0
#define CHAN_OUTPUT_WAIT_DRAIN		1
#define CHAN_OUTPUT_WAIT_IEOF		2
#define CHAN_OUTPUT_CLOSED		3

#define CHAN_CLOSE_SENT			0x01
#define CHAN_CLOSE_RCVD			0x02
#define CHAN_EOF_SENT			0x04
#define CHAN_EOF_RCVD			0x08

/* check whether 'efd' is still in use */
#define CHANNEL_EFD_INPUT_ACTIVE(c) \
	(compat20 && c->extended_usage == CHAN_EXTENDED_READ && \
	(c->efd != -1 || \
	buffer_len(&c->extended) > 0))
#define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
	(compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \
	((c->efd != -1 && !(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD))) || \
	buffer_len(&c->extended) > 0))

/* channel management */

Channel	*channel_lookup(int);
Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int);
void	 channel_set_fds(int, int, int, int, int, int, u_int);
void	 channel_free(Channel *);
void	 channel_free_all(void);
void	 channel_stop_listening(void);

void	 channel_send_open(int);
void	 channel_request_start(int, char *, int);
void	 channel_register_cleanup(int, channel_callback_fn *);
void	 channel_register_confirm(int, channel_callback_fn *, void *);
void	 channel_register_filter(int, channel_filter_fn *);
void	 channel_cancel_cleanup(int);
int	 channel_close_fd(int *);
void	 channel_send_window_changes(void);

/* protocol handler */

void	 channel_input_close(int, u_int32_t, void *);
void	 channel_input_close_confirmation(int, u_int32_t, void *);
void	 channel_input_data(int, u_int32_t, void *);
void	 channel_input_extended_data(int, u_int32_t, void *);
void	 channel_input_ieof(int, u_int32_t, void *);
void	 channel_input_oclose(int, u_int32_t, void *);
void	 channel_input_open_confirmation(int, u_int32_t, void *);
void	 channel_input_open_failure(int, u_int32_t, void *);
void	 channel_input_port_open(int, u_int32_t, void *);
void	 channel_input_window_adjust(int, u_int32_t, void *);

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

void	 channel_prepare_select(fd_set **, fd_set **, int *, u_int*, int);
void     channel_after_select(fd_set *, fd_set *);
void     channel_output_poll(void);

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

/* tcp forwarding */
void	 channel_set_af(int af);
void     channel_permit_all_opens(void);
void	 channel_add_permitted_opens(char *, int);
void	 channel_clear_permitted_opens(void);
void     channel_input_port_forward_request(int, int);
int	 channel_connect_to(const char *, u_short);
int	 channel_connect_by_listen_address(u_short);
void	 channel_request_remote_forwarding(u_short, const char *, u_short);
void	 channel_request_rforward_cancel(u_short port);
int	 channel_setup_local_fwd_listener(u_short, const char *, u_short, int);
int	 channel_setup_remote_fwd_listener(const char *, u_short, int);
int	 channel_cancel_rport_listener(const char *, u_short);

/* x11 forwarding */

int	 x11_connect_display(void);
int	 x11_create_display_inet(int, int, int, u_int *);
void     x11_input_open(int, u_int32_t, void *);
void	 x11_request_forwarding_with_spoofing(int, const char *, const char *);
void	 deny_input_open(int, u_int32_t, void *);

/* agent forwarding */

void	 auth_request_forwarding(void);

/* channel close */

int	 chan_is_dead(Channel *, int);
void	 chan_mark_dead(Channel *);

/* channel events */

void	 chan_rcvd_oclose(Channel *);
void	 chan_read_failed(Channel *);
void	 chan_ibuf_empty(Channel *);

void	 chan_rcvd_ieof(Channel *);
void	 chan_write_failed(Channel *);
void	 chan_obuf_empty(Channel *);

#endif
Commit	Line	Data
2c9a4d41	1	/* $OpenBSD: channels.h,v 1.75 2004/10/29 21:47:15 djm Exp $ */
93c3b6de	2
bcbf86ec	3	/*
	4	* Author: Tatu Ylonen <ylo@cs.hut.fi>
	5	* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
	6	* All rights reserved
	7	*
	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".
	13	*/
	14	/*
8ab5f6b2	15	* Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
bcbf86ec	16	*
	17	* Redistribution and use in source and binary forms, with or without
	18	* modification, are permitted provided that the following conditions
	19	* are met:
	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.
	25	*
	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.
	36	*/
8efc0c15	37
8e7895b8	38	#ifndef CHANNEL_H
8e7895b8	39	#define CHANNEL_H
8efc0c15	40
01794848	41	#include "buffer.h"
01794848	42
8efc0c15	43	/* Definitions for channel types. */
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
0490e609	56	#define SSH_CHANNEL_DYNAMIC 13
6fd8622b	57	#define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
6fd8622b	58	#define SSH_CHANNEL_MAX_TYPE 15
8efc0c15	59
27c47c0a	60	#define SSH_CHANNEL_PATH_LEN 256
719fc62f	61
2e73a022	62	struct Channel;
	63	typedef struct Channel Channel;
	64
2a1e4639	65	typedef void channel_callback_fn(int, void *);
2a1e4639	66	typedef int channel_filter_fn(struct Channel , char , int);
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 */
368e9dfc	72	u_int istate; /* input from channel (state of receive half) */
368e9dfc	73	u_int ostate; /* output to channel (state of transmit half) */
7e7327a1	74	int flags; /* close sent/rcvd */
7368a6c8	75	int rfd; /* read fd */
	76	int wfd; /* write fd */
	77	int efd; /* extended fd */
	78	int sock; /* sock fd */
5e96b616	79	int ctl_fd; /* control fd (client sharing) */
0ae4fe1d	80	int isatty; /* rfd is a tty */
21c2c5cd	81	int wfd_isatty; /* wfd is a tty */
2c9a4d41	82	int client_tty; /* (client) TTY has been requested */
639cb8ab	83	int force_drain; /* force close on iEOF */
639cb8ab	84	int delayed; /* fdset hack */
5260325f	85	Buffer input; /* data read from socket, to be sent over
	86	* encrypted connection */
	87	Buffer output; /* data received over encrypted connection for
	88	* send on socket */
7368a6c8	89	Buffer extended;
719fc62f	90	char path[SSH_CHANNEL_PATH_LEN];
719fc62f	91	/* path for unix domain sockets, or host name for forwards */
5260325f	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 */
7368a6c8	95
f91d9a89	96	u_int remote_window;
	97	u_int remote_maxpacket;
	98	u_int local_window;
	99	u_int local_window_max;
	100	u_int local_consumed;
	101	u_int local_maxpacket;
7368a6c8	102	int extended_usage;
ac151b18	103	int single_connection;
7368a6c8	104
	105	char ctype; / type */
	106
1d1ffb87	107	/* callback */
05ca0898	108	channel_callback_fn *confirm;
3cf2be58	109	channel_callback_fn *detach_user;
5e96b616	110	void *confirm_ctx;
2e73a022	111
	112	/* filter */
	113	channel_filter_fn *input_filter;
	114	};
7368a6c8	115
	116	#define CHAN_EXTENDED_IGNORE 0
	117	#define CHAN_EXTENDED_READ 1
	118	#define CHAN_EXTENDED_WRITE 2
	119
bcbf86ec	120	/* default window/packet sizes for tcp/x11-fwd-channel */
ea9700ba	121	#define CHAN_SES_PACKET_DEFAULT (32*1024)
	122	#define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT)
	123	#define CHAN_TCP_PACKET_DEFAULT (32*1024)
	124	#define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT)
	125	#define CHAN_X11_PACKET_DEFAULT (16*1024)
	126	#define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT)
bcbf86ec	127
8e7895b8	128	/* possible input states */
368e9dfc	129	#define CHAN_INPUT_OPEN 0
	130	#define CHAN_INPUT_WAIT_DRAIN 1
	131	#define CHAN_INPUT_WAIT_OCLOSE 2
	132	#define CHAN_INPUT_CLOSED 3
bcbf86ec	133
8e7895b8	134	/* possible output states */
368e9dfc	135	#define CHAN_OUTPUT_OPEN 0
	136	#define CHAN_OUTPUT_WAIT_DRAIN 1
	137	#define CHAN_OUTPUT_WAIT_IEOF 2
	138	#define CHAN_OUTPUT_CLOSED 3
8e7895b8	139
	140	#define CHAN_CLOSE_SENT 0x01
	141	#define CHAN_CLOSE_RCVD 0x02
d2296ed7	142	#define CHAN_EOF_SENT 0x04
	143	#define CHAN_EOF_RCVD 0x08
	144
	145	/* check whether 'efd' is still in use */
	146	#define CHANNEL_EFD_INPUT_ACTIVE(c) \
	147	(compat20 && c->extended_usage == CHAN_EXTENDED_READ && \
	148	(c->efd != -1 \|\| \
	149	buffer_len(&c->extended) > 0))
	150	#define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
	151	(compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \
6c112aca	152	((c->efd != -1 && !(c->flags & (CHAN_EOF_RCVD\|CHAN_CLOSE_RCVD))) \|\| \
d2296ed7	153	buffer_len(&c->extended) > 0))
8e7895b8	154
8e7895b8	155	/* channel management */
8e7895b8	156
2a1e4639	157	Channel *channel_lookup(int);
f91d9a89	158	Channel channel_new(char , int, int, int, int, u_int, u_int, int, char *, int);
ea9700ba	159	void channel_set_fds(int, int, int, int, int, int, u_int);
3cf2be58	160	void channel_free(Channel *);
3cf2be58	161	void channel_free_all(void);
3cf2be58	162	void channel_stop_listening(void);
255cabd9	163
255cabd9	164	void channel_send_open(int);
255cabd9	165	void channel_request_start(int, char *, int);
255cabd9	166	void channel_register_cleanup(int, channel_callback_fn *);
5e96b616	167	void channel_register_confirm(int, channel_callback_fn , void );
255cabd9	168	void channel_register_filter(int, channel_filter_fn *);
255cabd9	169	void channel_cancel_cleanup(int);
489aa2e9	170	int channel_close_fd(int *);
5e96b616	171	void channel_send_window_changes(void);
7368a6c8	172
8e7895b8	173	/* protocol handler */
7368a6c8	174
7819b5c3	175	void channel_input_close(int, u_int32_t, void *);
	176	void channel_input_close_confirmation(int, u_int32_t, void *);
	177	void channel_input_data(int, u_int32_t, void *);
	178	void channel_input_extended_data(int, u_int32_t, void *);
	179	void channel_input_ieof(int, u_int32_t, void *);
	180	void channel_input_oclose(int, u_int32_t, void *);
	181	void channel_input_open_confirmation(int, u_int32_t, void *);
	182	void channel_input_open_failure(int, u_int32_t, void *);
	183	void channel_input_port_open(int, u_int32_t, void *);
	184	void channel_input_window_adjust(int, u_int32_t, void *);
7368a6c8	185
8e7895b8	186	/* file descriptor handling (read/write) */
7368a6c8	187
9a995072	188	void channel_prepare_select(fd_set , fd_set , int , u_int, int);
255cabd9	189	void channel_after_select(fd_set , fd_set );
255cabd9	190	void channel_output_poll(void);
7368a6c8	191
255cabd9	192	int channel_not_very_much_buffered_data(void);
255cabd9	193	void channel_close_all(void);
255cabd9	194	int channel_still_open(void);
	195	char *channel_open_message(void);
	196	int channel_find_open(void);
7368a6c8	197
5e4a7219	198	/* tcp forwarding */
5e4a7219	199	void channel_set_af(int af);
255cabd9	200	void channel_permit_all_opens(void);
	201	void channel_add_permitted_opens(char *, int);
	202	void channel_clear_permitted_opens(void);
	203	void channel_input_port_forward_request(int, int);
	204	int channel_connect_to(const char *, u_short);
b3f8a79c	205	int channel_connect_by_listen_address(u_short);
255cabd9	206	void channel_request_remote_forwarding(u_short, const char *, u_short);
d740ec16	207	void channel_request_rforward_cancel(u_short port);
5641aefa	208	int channel_setup_local_fwd_listener(u_short, const char *, u_short, int);
5641aefa	209	int channel_setup_remote_fwd_listener(const char *, u_short, int);
d740ec16	210	int channel_cancel_rport_listener(const char *, u_short);
7368a6c8	211
8e7895b8	212	/* x11 forwarding */
7368a6c8	213
255cabd9	214	int x11_connect_display(void);
57f228e8	215	int x11_create_display_inet(int, int, int, u_int *);
7819b5c3	216	void x11_input_open(int, u_int32_t, void *);
255cabd9	217	void x11_request_forwarding_with_spoofing(int, const char , const char );
7819b5c3	218	void deny_input_open(int, u_int32_t, void *);
7368a6c8	219
8e7895b8	220	/* agent forwarding */
7368a6c8	221
255cabd9	222	void auth_request_forwarding(void);
7368a6c8	223
8e7895b8	224	/* channel close */
7e7327a1	225
418e724c	226	int chan_is_dead(Channel *, int);
255cabd9	227	void chan_mark_dead(Channel *);
255cabd9	228
70bef40e	229	/* channel events */
8e7895b8	230
70bef40e	231	void chan_rcvd_oclose(Channel *);
	232	void chan_read_failed(Channel *);
	233	void chan_ibuf_empty(Channel *);
8e7895b8	234
70bef40e	235	void chan_rcvd_ieof(Channel *);
	236	void chan_write_failed(Channel *);
	237	void chan_obuf_empty(Channel *);
8e7895b8	238
8efc0c15	239	#endif