-/* RCSID("$Id$"); */
+/* $OpenBSD: channels.h,v 1.103 2010/01/26 01:28:35 djm Exp $ */
-#ifndef CHANNELS_H
-#define CHANNELS_H
+/*
+ * 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_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 */
-/* SSH_CHANNEL_AUTH_FD 6 authentication fd */
-#define SSH_CHANNEL_AUTH_SOCKET 7 /* authentication socket */
-/* SSH_CHANNEL_AUTH_SOCKET_FD 8 connection to auth socket */
-#define SSH_CHANNEL_X11_OPEN 9 /* reading first X11 packet */
-#define SSH_CHANNEL_INPUT_DRAINING 10 /* sending remaining data to conn */
-#define SSH_CHANNEL_OUTPUT_DRAINING 11 /* sending remaining data to app */
-
-/* Data structure for channel data. This is iniailized in channel_allocate
- and cleared in channel_free. */
-
-typedef 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;
- int ostate;
- int x11;
- int sock; /* data socket, linked to this channel */
- Buffer input; /* data read from socket, to be sent over encrypted connection */
- Buffer output; /* data received over encrypted connection for send on socket */
- 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 */
-} Channel;
+#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_MUX_LISTENER 15 /* Listener for mux conn. */
+#define SSH_CHANNEL_MUX_CLIENT 16 /* Conn. to mux slave */
+#define SSH_CHANNEL_MAX_TYPE 17
+
+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;
+};
+
+/* Callbacks for mux channels back into client-specific code */
+typedef int mux_callback_fn(struct Channel *);
+
+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_chan; /* control channel (multiplexed connections) */
+ 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; /* post-select handlers for newly created
+ * channels are delayed until the first call
+ * to a matching pre-select handler.
+ * this way post-select handlers are not
+ * accidenly called if a FD gets reused */
+ 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;
+
+ /* multiplexing protocol hook, called for each packet received */
+ mux_callback_fn *mux_rcb;
+ void *mux_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_LOCAL 0x10
+
+#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_stdio_fwd(const char*, u_short, int, int);
+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
andersk / openssh.git / blobdiff