fdce75a19b
"non-echoed" characters are still echoed back in a null packet, as well as pad passwords sent to not give hints to the length otherwise. Obtained from: OpenBSD
296 lines
11 KiB
C
296 lines
11 KiB
C
/*
|
|
* 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("$FreeBSD$"); */
|
|
/* RCSID("$OpenBSD: channels.h,v 1.22 2000/10/27 07:48:22 markus Exp $"); */
|
|
|
|
#ifndef CHANNELS_H
|
|
#define CHANNELS_H
|
|
|
|
/* Definitions for channel types. */
|
|
#define SSH_CHANNEL_FREE 0 /* This channel is free (unused). */
|
|
#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_MAX_TYPE 11
|
|
|
|
/*
|
|
* Data structure for channel data. This is iniailized in channel_allocate
|
|
* 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[200]; /* 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);
|
|
|
|
int
|
|
channel_new(char *ctype, int type, int rfd, int wfd, int efd,
|
|
int window, int maxpack, int extended_usage, char *remote_name,
|
|
int nonblock);
|
|
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);
|
|
void channel_input_open(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.
|
|
*/
|
|
int channel_allocate(int type, int sock, char *remote_name);
|
|
|
|
/* Free the channel and close its socket. */
|
|
void channel_free(int channel);
|
|
|
|
/* Add any bits relevant to channels in select bitmasks. */
|
|
void channel_prepare_select(fd_set * readset, fd_set * writeset);
|
|
|
|
/*
|
|
* 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 the maximum file descriptor number used by the channels. */
|
|
int channel_max_fd(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. This never returns if there was an
|
|
* error.
|
|
*/
|
|
void
|
|
channel_request_local_forwarding(u_short port, const char *host,
|
|
u_short remote_port, int gateway_ports);
|
|
|
|
/*
|
|
* 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 in SSH_MSG_PORT_OPEN. 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);
|
|
|
|
/*
|
|
* 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 x11_connect_display(void);
|
|
|
|
#endif
|