-/* RCSID("$Id$"); */
-
-#ifndef CHANNELS_H
-#define CHANNELS_H
+/* $OpenBSD: channels.h,v 1.70 2002/06/24 14:33:27 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_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_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
+#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
-/*
- * Data structure for channel data. This is iniailized in channel_allocate
- * and cleared in channel_free.
- */
-typedef void channel_callback_fn(int id, void *arg);
+#define SSH_CHANNEL_PATH_LEN 256
+
+struct Channel;
+typedef struct Channel Channel;
-typedef struct 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 */
- /* 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) */
+ 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[200]; /* path for unix domain sockets, or host name
- * for forwards */
+ 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;
+ 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 *cb_fn;
- void *cb_arg;
- int cb_event;
- channel_callback_fn *dettach_user;
-} Channel;
+ /* 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
-void channel_set_fds(int id, int rfd, int wfd, int efd, int extusage);
-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_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);
-
-void channel_input_channel_request(int type, int plen);
-void channel_input_close(int type, int plen);
-void channel_input_close_confirmation(int type, int plen);
-void channel_input_data(int type, int plen);
-void channel_input_extended_data(int type, int plen);
-void channel_input_ieof(int type, int plen);
-void channel_input_oclose(int type, int plen);
-void channel_input_open_confirmation(int type, int plen);
-void channel_input_open_failure(int type, int plen);
-void channel_input_port_open(int type, int plen);
-void channel_input_window_adjust(int type, int plen);
-void channel_input_open(int type, int plen);
-
-/* 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);
-
-/*
- * 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);
-
-/*
- * 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(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 if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
- * This starts forwarding authentication requests.
- */
-void 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);
-
-/* XXX */
-int channel_connect_to(const char *host, u_short host_port);
+/* 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);
+void auth_input_open_request(int, u_int32_t, 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