[gssapi-openssh.git] / openssh / channels.h

/*	$OpenBSD: channels.h,v 1.71 2003/09/23 20:41:11 markus 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     isatty;		/* rfd is a tty */
	int     wfd_isatty;	/* wfd is a tty */
	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;

	/* 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	 channel_register_filter(int, channel_filter_fn *);
void	 channel_cancel_cleanup(int);
int	 channel_close_fd(int *);

/* 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 *, 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);
int	 channel_setup_local_fwd_listener(u_short, const char *, u_short, int);
int	 channel_setup_remote_fwd_listener(const char *, u_short, int);

/* 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
cdd66111	1	/* $OpenBSD: channels.h,v 1.71 2003/09/23 20:41:11 markus Exp $ */
e9a17296	2
3c0ef626	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	/*
e9a17296	15	* Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved.
3c0ef626	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	*/
3c0ef626	37
	38	#ifndef CHANNEL_H
	39	#define CHANNEL_H
	40
	41	#include "buffer.h"
	42
	43	/* Definitions for channel types. */
	44	#define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */
	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 */
	48	#define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
	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 */
	54	#define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */
	55	#define SSH_CHANNEL_CONNECTING 12
	56	#define SSH_CHANNEL_DYNAMIC 13
	57	#define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */
	58	#define SSH_CHANNEL_MAX_TYPE 15
	59
	60	#define SSH_CHANNEL_PATH_LEN 256
	61
	62	struct Channel;
	63	typedef struct Channel Channel;
	64
	65	typedef void channel_callback_fn(int, void *);
	66	typedef int channel_filter_fn(struct Channel , char , int);
	67
	68	struct Channel {
	69	int type; /* channel type/state */
	70	int self; /* my own channel identifier */
	71	int remote_id; /* channel identifier for remote peer */
e9a17296	72	u_int istate; /* input from channel (state of receive half) */
e9a17296	73	u_int ostate; /* output to channel (state of transmit half) */
3c0ef626	74	int flags; /* close sent/rcvd */
	75	int rfd; /* read fd */
	76	int wfd; /* write fd */
	77	int efd; /* extended fd */
	78	int sock; /* sock fd */
	79	int isatty; /* rfd is a tty */
41b2f314	80	int wfd_isatty; /* wfd is a tty */
3c0ef626	81	int force_drain; /* force close on iEOF */
	82	int delayed; /* fdset hack */
	83	Buffer input; /* data read from socket, to be sent over
	84	* encrypted connection */
	85	Buffer output; /* data received over encrypted connection for
	86	* send on socket */
	87	Buffer extended;
	88	char path[SSH_CHANNEL_PATH_LEN];
	89	/* path for unix domain sockets, or host name for forwards */
	90	int listening_port; /* port being listened for forwards */
	91	int host_port; /* remote port to connect for forwards */
	92	char remote_name; / remote hostname */
	93
680cee3b	94	u_int remote_window;
	95	u_int remote_maxpacket;
	96	u_int local_window;
	97	u_int local_window_max;
	98	u_int local_consumed;
	99	u_int local_maxpacket;
3c0ef626	100	int extended_usage;
e9a17296	101	int single_connection;
3c0ef626	102
	103	char ctype; / type */
	104
	105	/* callback */
e9a17296	106	channel_callback_fn *confirm;
3c0ef626	107	channel_callback_fn *detach_user;
	108
	109	/* filter */
	110	channel_filter_fn *input_filter;
	111	};
	112
	113	#define CHAN_EXTENDED_IGNORE 0
	114	#define CHAN_EXTENDED_READ 1
	115	#define CHAN_EXTENDED_WRITE 2
	116
	117	/* default window/packet sizes for tcp/x11-fwd-channel */
e9a17296	118	#define CHAN_SES_PACKET_DEFAULT (32*1024)
	119	#define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT)
	120	#define CHAN_TCP_PACKET_DEFAULT (32*1024)
	121	#define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT)
	122	#define CHAN_X11_PACKET_DEFAULT (16*1024)
	123	#define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT)
3c0ef626	124
3c0ef626	125	/* possible input states */
e9a17296	126	#define CHAN_INPUT_OPEN 0
	127	#define CHAN_INPUT_WAIT_DRAIN 1
	128	#define CHAN_INPUT_WAIT_OCLOSE 2
	129	#define CHAN_INPUT_CLOSED 3
3c0ef626	130
3c0ef626	131	/* possible output states */
e9a17296	132	#define CHAN_OUTPUT_OPEN 0
	133	#define CHAN_OUTPUT_WAIT_DRAIN 1
	134	#define CHAN_OUTPUT_WAIT_IEOF 2
	135	#define CHAN_OUTPUT_CLOSED 3
3c0ef626	136
	137	#define CHAN_CLOSE_SENT 0x01
	138	#define CHAN_CLOSE_RCVD 0x02
700318f3	139	#define CHAN_EOF_SENT 0x04
	140	#define CHAN_EOF_RCVD 0x08
	141
	142	/* check whether 'efd' is still in use */
	143	#define CHANNEL_EFD_INPUT_ACTIVE(c) \
	144	(compat20 && c->extended_usage == CHAN_EXTENDED_READ && \
	145	(c->efd != -1 \|\| \
	146	buffer_len(&c->extended) > 0))
	147	#define CHANNEL_EFD_OUTPUT_ACTIVE(c) \
	148	(compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \
	149	((c->efd != -1 && !(c->flags & (CHAN_EOF_RCVD\|CHAN_CLOSE_RCVD))) \|\| \
	150	buffer_len(&c->extended) > 0))
3c0ef626	151
	152	/* channel management */
	153
	154	Channel *channel_lookup(int);
680cee3b	155	Channel channel_new(char , int, int, int, int, u_int, u_int, int, char *, int);
e9a17296	156	void channel_set_fds(int, int, int, int, int, int, u_int);
3c0ef626	157	void channel_free(Channel *);
	158	void channel_free_all(void);
	159	void channel_stop_listening(void);
	160
	161	void channel_send_open(int);
3c0ef626	162	void channel_request_start(int, char *, int);
3c0ef626	163	void channel_register_cleanup(int, channel_callback_fn *);
e9a17296	164	void channel_register_confirm(int, channel_callback_fn *);
3c0ef626	165	void channel_register_filter(int, channel_filter_fn *);
	166	void channel_cancel_cleanup(int);
	167	int channel_close_fd(int *);
	168
	169	/* protocol handler */
	170
e9a17296	171	void channel_input_close(int, u_int32_t, void *);
	172	void channel_input_close_confirmation(int, u_int32_t, void *);
	173	void channel_input_data(int, u_int32_t, void *);
	174	void channel_input_extended_data(int, u_int32_t, void *);
	175	void channel_input_ieof(int, u_int32_t, void *);
	176	void channel_input_oclose(int, u_int32_t, void *);
	177	void channel_input_open_confirmation(int, u_int32_t, void *);
	178	void channel_input_open_failure(int, u_int32_t, void *);
	179	void channel_input_port_open(int, u_int32_t, void *);
	180	void channel_input_window_adjust(int, u_int32_t, void *);
3c0ef626	181
	182	/* file descriptor handling (read/write) */
	183
	184	void channel_prepare_select(fd_set , fd_set , int , int, int);
	185	void channel_after_select(fd_set , fd_set );
	186	void channel_output_poll(void);
	187
	188	int channel_not_very_much_buffered_data(void);
	189	void channel_close_all(void);
	190	int channel_still_open(void);
	191	char *channel_open_message(void);
	192	int channel_find_open(void);
	193
	194	/* tcp forwarding */
	195	void channel_set_af(int af);
	196	void channel_permit_all_opens(void);
	197	void channel_add_permitted_opens(char *, int);
	198	void channel_clear_permitted_opens(void);
	199	void channel_input_port_forward_request(int, int);
	200	int channel_connect_to(const char *, u_short);
	201	int channel_connect_by_listen_address(u_short);
	202	void channel_request_remote_forwarding(u_short, const char *, u_short);
e9a17296	203	int channel_setup_local_fwd_listener(u_short, const char *, u_short, int);
e9a17296	204	int channel_setup_remote_fwd_listener(const char *, u_short, int);
3c0ef626	205
	206	/* x11 forwarding */
	207
	208	int x11_connect_display(void);
680cee3b	209	int x11_create_display_inet(int, int, int, u_int *);
e9a17296	210	void x11_input_open(int, u_int32_t, void *);
3c0ef626	211	void x11_request_forwarding_with_spoofing(int, const char , const char );
e9a17296	212	void deny_input_open(int, u_int32_t, void *);
3c0ef626	213
	214	/* agent forwarding */
	215
	216	void auth_request_forwarding(void);
3c0ef626	217
	218	/* channel close */
	219
	220	int chan_is_dead(Channel *, int);
	221	void chan_mark_dead(Channel *);
3c0ef626	222
e9a17296	223	/* channel events */
3c0ef626	224
e9a17296	225	void chan_rcvd_oclose(Channel *);
	226	void chan_read_failed(Channel *);
	227	void chan_ibuf_empty(Channel *);
3c0ef626	228
e9a17296	229	void chan_rcvd_ieof(Channel *);
	230	void chan_write_failed(Channel *);
	231	void chan_obuf_empty(Channel *);
3c0ef626	232
3c0ef626	233	#endif