~ubuntu-branches/ubuntu/lucid/openssh/lucid

/* $OpenBSD: channels.h,v 1.98 2009/02/12 03:00:56 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

/* 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

struct Channel;

typedef struct Channel Channel;

typedef void channel_callback_fn(int, void *);

typedef int channel_infilter_fn(struct Channel *, char *, int);

typedef void channel_filter_cleanup_fn(int, void *);

typedef u_char *channel_outfilter_fn(struct Channel *, u_char **, u_int *);

/* Channel success/failure callbacks */

typedef void channel_confirm_cb(int, struct Channel *, void *);

typedef void channel_confirm_abandon_cb(struct Channel *, void *);

struct channel_confirm {

	TAILQ_ENTRY(channel_confirm) entry;

	channel_confirm_cb *cb;

	channel_confirm_abandon_cb *abandon_cb;

	void *ctx;

};

TAILQ_HEAD(channel_confirms, channel_confirm);

/* Context for non-blocking connects */

struct channel_connect {

	char *host;

	int port;

	struct addrinfo *ai, *aitop;

};

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;

		/* 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	*open_confirm;

	void			*open_confirm_ctx;

	channel_callback_fn	*detach_user;

	int			detach_close;

	struct channel_confirms	status_confirms;

	/* filter */

	channel_infilter_fn	*input_filter;

	channel_outfilter_fn	*output_filter;

	void			*filter_ctx;

	channel_filter_cleanup_fn *filter_cleanup;

	/* keep boundaries */

	int     		datagram;

	/* non-blocking connect */

	struct channel_connect	connect_ctx;

};

#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	(64*CHAN_SES_PACKET_DEFAULT)

#define CHAN_TCP_PACKET_DEFAULT	(32*1024)

#define CHAN_TCP_WINDOW_DEFAULT	(64*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

#define CHAN_RBUF	16*1024

/* 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_by_id(int);

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, 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 *, int);

void	 channel_register_open_confirm(int, channel_callback_fn *, void *);

void	 channel_register_filter(int, channel_infilter_fn *,

    channel_outfilter_fn *, channel_filter_cleanup_fn *, void *);

void	 channel_register_status_confirm(int, channel_confirm_cb *,

    channel_confirm_abandon_cb *, void *);

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 *);

void	 channel_input_status_confirm(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);

int	 channel_add_adm_permitted_opens(char *, int);

void	 channel_clear_permitted_opens(void);

void	 channel_clear_adm_permitted_opens(void);

void 	 channel_print_adm_permitted_opens(void);

int      channel_input_port_forward_request(int, int);

Channel	*channel_connect_to(const char *, u_short, char *, char *);

Channel	*channel_connect_by_listen_address(u_short, char *, char *);

int	 channel_request_remote_forwarding(const char *, u_short,

	     const char *, u_short);

int	 channel_setup_local_fwd_listener(const char *, u_short,

	     const char *, u_short, int);

void	 channel_request_rforward_cancel(const char *host, u_short port);

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

void     x11_input_open(int, u_int32_t, void *);

void	 x11_request_forwarding_with_spoofing(int, const char *, 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_rcvd_eow(Channel *);	/* SSH2-only */

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