1295367Sdes/* $OpenBSD: channels.h,v 1.118 2015/07/01 02:26:31 djm Exp $ */ 292559Sdes 365668Skris/* 465668Skris * Author: Tatu Ylonen <ylo@cs.hut.fi> 565668Skris * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 665668Skris * All rights reserved 765668Skris * 865668Skris * As far as I am concerned, the code I have written for this software 965668Skris * can be used freely for any purpose. Any derived versions of this 1065668Skris * software must be clearly marked as such, and if the derived work is 1165668Skris * incompatible with the protocol description in the RFC file, it must be 1265668Skris * called by a name other than "ssh" or "Secure Shell". 1365668Skris */ 1465668Skris/* 1592559Sdes * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. 1665668Skris * 1765668Skris * Redistribution and use in source and binary forms, with or without 1865668Skris * modification, are permitted provided that the following conditions 1965668Skris * are met: 2065668Skris * 1. Redistributions of source code must retain the above copyright 2165668Skris * notice, this list of conditions and the following disclaimer. 2265668Skris * 2. Redistributions in binary form must reproduce the above copyright 2365668Skris * notice, this list of conditions and the following disclaimer in the 2465668Skris * documentation and/or other materials provided with the distribution. 2565668Skris * 2665668Skris * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 2765668Skris * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 2865668Skris * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 2965668Skris * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 3065668Skris * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 3165668Skris * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 3265668Skris * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 3365668Skris * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 3465668Skris * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 3565668Skris * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 3665668Skris */ 3757429Smarkm 3892559Sdes#ifndef CHANNEL_H 3992559Sdes#define CHANNEL_H 4057429Smarkm 4157429Smarkm/* Definitions for channel types. */ 4257429Smarkm#define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */ 4357429Smarkm#define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */ 4457429Smarkm#define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */ 4557429Smarkm#define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */ 4657429Smarkm#define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */ 4760573Skris#define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */ 4860573Skris#define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */ 4960573Skris#define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */ 5060573Skris#define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */ 5160573Skris#define SSH_CHANNEL_LARVAL 10 /* larval session */ 5276262Sgreen#define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */ 5376262Sgreen#define SSH_CHANNEL_CONNECTING 12 5476262Sgreen#define SSH_CHANNEL_DYNAMIC 13 5592559Sdes#define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */ 56204917Sdes#define SSH_CHANNEL_MUX_LISTENER 15 /* Listener for mux conn. */ 57204917Sdes#define SSH_CHANNEL_MUX_CLIENT 16 /* Conn. to mux slave */ 58255767Sdes#define SSH_CHANNEL_ABANDONED 17 /* Abandoned session, eg mux */ 59295367Sdes#define SSH_CHANNEL_UNIX_LISTENER 18 /* Listening on a domain socket. */ 60295367Sdes#define SSH_CHANNEL_RUNIX_LISTENER 19 /* Listening to a R-style domain socket. */ 61295367Sdes#define SSH_CHANNEL_MAX_TYPE 20 6257429Smarkm 63240075Sdes#define CHANNEL_CANCEL_PORT_STATIC -1 64240075Sdes 6565668Skrisstruct Channel; 6665668Skristypedef struct Channel Channel; 6765668Skris 68215116Sdestypedef void channel_open_fn(int, int, void *); 6992559Sdestypedef void channel_callback_fn(int, void *); 70157019Sdestypedef int channel_infilter_fn(struct Channel *, char *, int); 71181111Sdestypedef void channel_filter_cleanup_fn(int, void *); 72157019Sdestypedef u_char *channel_outfilter_fn(struct Channel *, u_char **, u_int *); 7357429Smarkm 74181111Sdes/* Channel success/failure callbacks */ 75181111Sdestypedef void channel_confirm_cb(int, struct Channel *, void *); 76181111Sdestypedef void channel_confirm_abandon_cb(struct Channel *, void *); 77181111Sdesstruct channel_confirm { 78181111Sdes TAILQ_ENTRY(channel_confirm) entry; 79181111Sdes channel_confirm_cb *cb; 80181111Sdes channel_confirm_abandon_cb *abandon_cb; 81181111Sdes void *ctx; 82181111Sdes}; 83181111SdesTAILQ_HEAD(channel_confirms, channel_confirm); 84181111Sdes 85181111Sdes/* Context for non-blocking connects */ 86181111Sdesstruct channel_connect { 87181111Sdes char *host; 88181111Sdes int port; 89181111Sdes struct addrinfo *ai, *aitop; 90181111Sdes}; 91181111Sdes 92204917Sdes/* Callbacks for mux channels back into client-specific code */ 93204917Sdestypedef int mux_callback_fn(struct Channel *); 94204917Sdes 9565668Skrisstruct Channel { 9657429Smarkm int type; /* channel type/state */ 9757429Smarkm int self; /* my own channel identifier */ 9857429Smarkm int remote_id; /* channel identifier for remote peer */ 9992559Sdes u_int istate; /* input from channel (state of receive half) */ 10092559Sdes u_int ostate; /* output to channel (state of transmit half) */ 10160573Skris int flags; /* close sent/rcvd */ 10260573Skris int rfd; /* read fd */ 10360573Skris int wfd; /* write fd */ 10460573Skris int efd; /* extended fd */ 10560573Skris int sock; /* sock fd */ 106204917Sdes int ctl_chan; /* control channel (multiplexed connections) */ 10774500Sgreen int isatty; /* rfd is a tty */ 108255767Sdes#ifdef _AIX 109106130Sdes int wfd_isatty; /* wfd is a tty */ 110255767Sdes#endif 111147005Sdes int client_tty; /* (client) TTY has been requested */ 11292559Sdes int force_drain; /* force close on iEOF */ 113240075Sdes time_t notbefore; /* Pause IO until deadline (time_t) */ 114204917Sdes int delayed; /* post-select handlers for newly created 115204917Sdes * channels are delayed until the first call 116295367Sdes * to a matching pre-select handler. 117204917Sdes * this way post-select handlers are not 118255767Sdes * accidentally called if a FD gets reused */ 11957429Smarkm Buffer input; /* data read from socket, to be sent over 12057429Smarkm * encrypted connection */ 12157429Smarkm Buffer output; /* data received over encrypted connection for 12257429Smarkm * send on socket */ 12360573Skris Buffer extended; 124192595Sdes char *path; 12592559Sdes /* path for unix domain sockets, or host name for forwards */ 12657429Smarkm int listening_port; /* port being listened for forwards */ 127240075Sdes char *listening_addr; /* addr being listened for forwards */ 12857429Smarkm int host_port; /* remote port to connect for forwards */ 12957429Smarkm char *remote_name; /* remote hostname */ 13060573Skris 13199063Sdes u_int remote_window; 13299063Sdes u_int remote_maxpacket; 13399063Sdes u_int local_window; 13499063Sdes u_int local_window_max; 13599063Sdes u_int local_consumed; 13699063Sdes u_int local_maxpacket; 13760573Skris int extended_usage; 13892559Sdes int single_connection; 13960573Skris 14060573Skris char *ctype; /* type */ 14160573Skris 14260573Skris /* callback */ 143215116Sdes channel_open_fn *open_confirm; 144181111Sdes void *open_confirm_ctx; 14592559Sdes channel_callback_fn *detach_user; 146157019Sdes int detach_close; 147181111Sdes struct channel_confirms status_confirms; 14860573Skris 14965668Skris /* filter */ 150157019Sdes channel_infilter_fn *input_filter; 151157019Sdes channel_outfilter_fn *output_filter; 152181111Sdes void *filter_ctx; 153181111Sdes channel_filter_cleanup_fn *filter_cleanup; 154157019Sdes 155181111Sdes /* keep boundaries */ 156181111Sdes int datagram; 157181111Sdes 158181111Sdes /* non-blocking connect */ 159181111Sdes struct channel_connect connect_ctx; 160204917Sdes 161204917Sdes /* multiplexing protocol hook, called for each packet received */ 162204917Sdes mux_callback_fn *mux_rcb; 163204917Sdes void *mux_ctx; 164215116Sdes int mux_pause; 16565668Skris}; 16665668Skris 16760573Skris#define CHAN_EXTENDED_IGNORE 0 16860573Skris#define CHAN_EXTENDED_READ 1 16960573Skris#define CHAN_EXTENDED_WRITE 2 17060573Skris 17165668Skris/* default window/packet sizes for tcp/x11-fwd-channel */ 17292559Sdes#define CHAN_SES_PACKET_DEFAULT (32*1024) 173181111Sdes#define CHAN_SES_WINDOW_DEFAULT (64*CHAN_SES_PACKET_DEFAULT) 17492559Sdes#define CHAN_TCP_PACKET_DEFAULT (32*1024) 175181111Sdes#define CHAN_TCP_WINDOW_DEFAULT (64*CHAN_TCP_PACKET_DEFAULT) 17692559Sdes#define CHAN_X11_PACKET_DEFAULT (16*1024) 17792559Sdes#define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT) 178224638Sbrooks 17992559Sdes/* possible input states */ 18092559Sdes#define CHAN_INPUT_OPEN 0 18192559Sdes#define CHAN_INPUT_WAIT_DRAIN 1 18292559Sdes#define CHAN_INPUT_WAIT_OCLOSE 2 18392559Sdes#define CHAN_INPUT_CLOSED 3 18465668Skris 18592559Sdes/* possible output states */ 18692559Sdes#define CHAN_OUTPUT_OPEN 0 18792559Sdes#define CHAN_OUTPUT_WAIT_DRAIN 1 18892559Sdes#define CHAN_OUTPUT_WAIT_IEOF 2 18992559Sdes#define CHAN_OUTPUT_CLOSED 3 19060573Skris 19192559Sdes#define CHAN_CLOSE_SENT 0x01 19292559Sdes#define CHAN_CLOSE_RCVD 0x02 19398684Sdes#define CHAN_EOF_SENT 0x04 19498684Sdes#define CHAN_EOF_RCVD 0x08 195204917Sdes#define CHAN_LOCAL 0x10 19660573Skris 197157019Sdes#define CHAN_RBUF 16*1024 198157019Sdes 19998684Sdes/* check whether 'efd' is still in use */ 20098684Sdes#define CHANNEL_EFD_INPUT_ACTIVE(c) \ 20198684Sdes (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \ 20298684Sdes (c->efd != -1 || \ 20398684Sdes buffer_len(&c->extended) > 0)) 20498684Sdes#define CHANNEL_EFD_OUTPUT_ACTIVE(c) \ 20598684Sdes (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \ 206149753Sdes c->efd != -1 && (!(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD)) || \ 20798684Sdes buffer_len(&c->extended) > 0)) 20898684Sdes 20992559Sdes/* channel management */ 21060573Skris 211157019SdesChannel *channel_by_id(int); 21292559SdesChannel *channel_lookup(int); 21399063SdesChannel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int); 214181111Sdesvoid channel_set_fds(int, int, int, int, int, int, int, u_int); 21592559Sdesvoid channel_free(Channel *); 21692559Sdesvoid channel_free_all(void); 21792559Sdesvoid channel_stop_listening(void); 21869587Sgreen 21992559Sdesvoid channel_send_open(int); 22092559Sdesvoid channel_request_start(int, char *, int); 221157019Sdesvoid channel_register_cleanup(int, channel_callback_fn *, int); 222215116Sdesvoid channel_register_open_confirm(int, channel_open_fn *, void *); 223181111Sdesvoid channel_register_filter(int, channel_infilter_fn *, 224181111Sdes channel_outfilter_fn *, channel_filter_cleanup_fn *, void *); 225181111Sdesvoid channel_register_status_confirm(int, channel_confirm_cb *, 226181111Sdes channel_confirm_abandon_cb *, void *); 22792559Sdesvoid channel_cancel_cleanup(int); 22892559Sdesint channel_close_fd(int *); 229137019Sdesvoid channel_send_window_changes(void); 23060573Skris 23192559Sdes/* protocol handler */ 23260573Skris 233295367Sdesint channel_input_close(int, u_int32_t, void *); 234295367Sdesint channel_input_close_confirmation(int, u_int32_t, void *); 235295367Sdesint channel_input_data(int, u_int32_t, void *); 236295367Sdesint channel_input_extended_data(int, u_int32_t, void *); 237295367Sdesint channel_input_ieof(int, u_int32_t, void *); 238295367Sdesint channel_input_oclose(int, u_int32_t, void *); 239295367Sdesint channel_input_open_confirmation(int, u_int32_t, void *); 240295367Sdesint channel_input_open_failure(int, u_int32_t, void *); 241295367Sdesint channel_input_port_open(int, u_int32_t, void *); 242295367Sdesint channel_input_window_adjust(int, u_int32_t, void *); 243295367Sdesint channel_input_status_confirm(int, u_int32_t, void *); 24460573Skris 24592559Sdes/* file descriptor handling (read/write) */ 24660573Skris 247240075Sdesvoid channel_prepare_select(fd_set **, fd_set **, int *, u_int*, 248240075Sdes time_t*, int); 24992559Sdesvoid channel_after_select(fd_set *, fd_set *); 25092559Sdesvoid channel_output_poll(void); 25160573Skris 25292559Sdesint channel_not_very_much_buffered_data(void); 25392559Sdesvoid channel_close_all(void); 25492559Sdesint channel_still_open(void); 25592559Sdeschar *channel_open_message(void); 25692559Sdesint channel_find_open(void); 25760573Skris 25892559Sdes/* tcp forwarding */ 259295367Sdesstruct Forward; 260295367Sdesstruct ForwardOptions; 26192559Sdesvoid channel_set_af(int af); 26292559Sdesvoid channel_permit_all_opens(void); 26392559Sdesvoid channel_add_permitted_opens(char *, int); 264162856Sdesint channel_add_adm_permitted_opens(char *, int); 265240075Sdesvoid channel_disable_adm_local_opens(void); 266240075Sdesvoid channel_update_permitted_opens(int, int); 26792559Sdesvoid channel_clear_permitted_opens(void); 268162856Sdesvoid channel_clear_adm_permitted_opens(void); 269181111Sdesvoid channel_print_adm_permitted_opens(void); 270295367Sdesint channel_input_port_forward_request(int, struct ForwardOptions *); 271295367SdesChannel *channel_connect_to_port(const char *, u_short, char *, char *); 272295367SdesChannel *channel_connect_to_path(const char *, char *, char *); 273204917SdesChannel *channel_connect_stdio_fwd(const char*, u_short, int, int); 274295367SdesChannel *channel_connect_by_listen_address(const char *, u_short, 275295367Sdes char *, char *); 276295367SdesChannel *channel_connect_by_listen_path(const char *, char *, char *); 277295367Sdesint channel_request_remote_forwarding(struct Forward *); 278295367Sdesint channel_setup_local_fwd_listener(struct Forward *, struct ForwardOptions *); 279295367Sdesint channel_request_rforward_cancel(struct Forward *); 280295367Sdesint channel_setup_remote_fwd_listener(struct Forward *, int *, struct ForwardOptions *); 281295367Sdesint channel_cancel_rport_listener(struct Forward *); 282295367Sdesint channel_cancel_lport_listener(struct Forward *, int, struct ForwardOptions *); 283240075Sdesint permitopen_port(const char *); 28460573Skris 28592559Sdes/* x11 forwarding */ 28660573Skris 287295367Sdesvoid channel_set_x11_refuse_time(u_int); 28892559Sdesint x11_connect_display(void); 289149753Sdesint x11_create_display_inet(int, int, int, u_int *, int **); 290295367Sdesint x11_input_open(int, u_int32_t, void *); 291149753Sdesvoid x11_request_forwarding_with_spoofing(int, const char *, const char *, 292226046Sdes const char *, int); 293295367Sdesint deny_input_open(int, u_int32_t, void *); 29460573Skris 29592559Sdes/* agent forwarding */ 29660573Skris 29792559Sdesvoid auth_request_forwarding(void); 29860573Skris 29992559Sdes/* channel close */ 30060573Skris 30192559Sdesint chan_is_dead(Channel *, int); 30292559Sdesvoid chan_mark_dead(Channel *); 30360573Skris 30492559Sdes/* channel events */ 30560573Skris 30692559Sdesvoid chan_rcvd_oclose(Channel *); 307181111Sdesvoid chan_rcvd_eow(Channel *); /* SSH2-only */ 30892559Sdesvoid chan_read_failed(Channel *); 30992559Sdesvoid chan_ibuf_empty(Channel *); 31076262Sgreen 31192559Sdesvoid chan_rcvd_ieof(Channel *); 31292559Sdesvoid chan_write_failed(Channel *); 31392559Sdesvoid chan_obuf_empty(Channel *); 31476262Sgreen 31557429Smarkm#endif 316