1 /* 2 * Copyright 2007 Sun Microsystems, Inc. All rights reserved. 3 * Use is subject to license terms. 4 */ 5 /* $OpenBSD: channels.h,v 1.70 2002/06/24 14:33:27 markus Exp $ */ 6 7 #ifndef _CHANNELS_H 8 #define _CHANNELS_H 9 10 #pragma ident "%Z%%M% %I% %E% SMI" 11 12 #ifdef __cplusplus 13 extern "C" { 14 #endif 15 16 17 /* 18 * Author: Tatu Ylonen <ylo@cs.hut.fi> 19 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 20 * All rights reserved 21 * 22 * As far as I am concerned, the code I have written for this software 23 * can be used freely for any purpose. Any derived versions of this 24 * software must be clearly marked as such, and if the derived work is 25 * incompatible with the protocol description in the RFC file, it must be 26 * called by a name other than "ssh" or "Secure Shell". 27 */ 28 /* 29 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. 30 * 31 * Redistribution and use in source and binary forms, with or without 32 * modification, are permitted provided that the following conditions 33 * are met: 34 * 1. Redistributions of source code must retain the above copyright 35 * notice, this list of conditions and the following disclaimer. 36 * 2. Redistributions in binary form must reproduce the above copyright 37 * notice, this list of conditions and the following disclaimer in the 38 * documentation and/or other materials provided with the distribution. 39 * 40 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 41 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 42 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 43 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 44 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 45 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 46 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 47 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 48 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 49 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 50 */ 51 52 #include "buffer.h" 53 54 /* Definitions for channel types. */ 55 #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */ 56 #define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */ 57 #define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */ 58 #define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */ 59 #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */ 60 #define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */ 61 #define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */ 62 #define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */ 63 #define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */ 64 #define SSH_CHANNEL_LARVAL 10 /* larval session */ 65 #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */ 66 #define SSH_CHANNEL_CONNECTING 12 67 #define SSH_CHANNEL_DYNAMIC 13 68 #define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */ 69 #define SSH_CHANNEL_MAX_TYPE 15 70 71 #define SSH_CHANNEL_PATH_LEN 256 72 73 struct Channel; 74 typedef struct Channel Channel; 75 76 typedef void channel_callback_fn(int, void *); 77 typedef int channel_filter_fn(struct Channel *, char *, int); 78 79 struct Channel { 80 int type; /* channel type/state */ 81 int self; /* my own channel identifier */ 82 int remote_id; /* channel identifier for remote peer */ 83 u_int istate; /* input from channel (state of receive half) */ 84 u_int ostate; /* output to channel (state of transmit half) */ 85 int wait_for_exit; /* no close till after exit-status is sent */ 86 int flags; /* close sent/rcvd */ 87 int rfd; /* read fd */ 88 int wfd; /* write fd */ 89 int efd; /* extended fd */ 90 int sock; /* sock fd */ 91 int isatty; /* rfd is a tty */ 92 int wfd_isatty; /* wfd is a tty */ 93 int force_drain; /* force close on iEOF */ 94 int delayed; /* fdset hack */ 95 Buffer input; /* data read from socket, to be sent over 96 * encrypted connection */ 97 Buffer output; /* data received over encrypted connection for 98 * send on socket */ 99 Buffer extended; 100 char path[SSH_CHANNEL_PATH_LEN]; 101 /* path for unix domain sockets, or host name for forwards */ 102 int listening_port; /* port being listened for forwards */ 103 int host_port; /* remote port to connect for forwards */ 104 char *remote_name; /* remote hostname */ 105 106 u_int remote_window; 107 u_int remote_maxpacket; 108 u_int local_window; 109 u_int local_window_max; 110 u_int local_consumed; 111 u_int local_maxpacket; 112 int extended_usage; 113 int single_connection; 114 115 char *ctype; /* type */ 116 117 /* callback */ 118 channel_callback_fn *confirm; 119 channel_callback_fn *detach_user; 120 121 /* filter */ 122 channel_filter_fn *input_filter; 123 }; 124 125 #define CHAN_EXTENDED_IGNORE 0 126 #define CHAN_EXTENDED_READ 1 127 #define CHAN_EXTENDED_WRITE 2 128 129 /* default window/packet sizes for tcp/x11-fwd-channel */ 130 #define CHAN_SES_PACKET_DEFAULT (32*1024) 131 #define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT) 132 #define CHAN_TCP_PACKET_DEFAULT (32*1024) 133 #define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT) 134 #define CHAN_X11_PACKET_DEFAULT (16*1024) 135 #define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT) 136 137 /* possible input states */ 138 #define CHAN_INPUT_OPEN 0 139 #define CHAN_INPUT_WAIT_DRAIN 1 140 #define CHAN_INPUT_WAIT_OCLOSE 2 141 #define CHAN_INPUT_CLOSED 3 142 143 /* possible output states */ 144 #define CHAN_OUTPUT_OPEN 0 145 #define CHAN_OUTPUT_WAIT_DRAIN 1 146 #define CHAN_OUTPUT_WAIT_IEOF 2 147 #define CHAN_OUTPUT_CLOSED 3 148 149 /* 150 * Other channel flag bits are specific to each type of channel and are 151 * defined locally with the code that uses them. 152 */ 153 #define CHAN_CLOSE_SENT 0x01 154 #define CHAN_CLOSE_RCVD 0x02 155 #define CHAN_EOF_SENT 0x04 156 #define CHAN_EOF_RCVD 0x08 157 158 /* check whether 'efd' is still in use */ 159 #define CHANNEL_EFD_INPUT_ACTIVE(c) \ 160 (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \ 161 (c->efd != -1 || \ 162 buffer_len(&c->extended) > 0)) 163 #define CHANNEL_EFD_OUTPUT_ACTIVE(c) \ 164 (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \ 165 ((c->efd != -1 && !(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD))) || \ 166 buffer_len(&c->extended) > 0)) 167 168 /* channel management */ 169 170 Channel *channel_lookup(int); 171 Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int); 172 void channel_set_fds(int, int, int, int, int, int, u_int); 173 void channel_set_wait_for_exit(int, int); 174 void channel_free(Channel *); 175 void channel_free_all(void); 176 void channel_stop_listening(void); 177 178 void channel_send_open(int); 179 void channel_request_start(int, char *, int); 180 void channel_register_cleanup(int, channel_callback_fn *); 181 void channel_register_confirm(int, channel_callback_fn *); 182 void channel_register_filter(int, channel_filter_fn *); 183 void channel_cancel_cleanup(int); 184 int channel_close_fd(int *); 185 186 /* protocol handler */ 187 188 void channel_input_close(int, u_int32_t, void *); 189 void channel_input_close_confirmation(int, u_int32_t, void *); 190 void channel_input_data(int, u_int32_t, void *); 191 void channel_input_extended_data(int, u_int32_t, void *); 192 void channel_input_ieof(int, u_int32_t, void *); 193 void channel_input_oclose(int, u_int32_t, void *); 194 void channel_input_open_confirmation(int, u_int32_t, void *); 195 void channel_input_open_failure(int, u_int32_t, void *); 196 void channel_input_port_open(int, u_int32_t, void *); 197 void channel_input_window_adjust(int, u_int32_t, void *); 198 199 /* file descriptor handling (read/write) */ 200 201 void channel_prepare_select(fd_set **, fd_set **, int *, int*, int); 202 void channel_after_select(fd_set *, fd_set *); 203 void channel_output_poll(void); 204 205 int channel_not_very_much_buffered_data(void); 206 void channel_close_all(void); 207 int channel_still_open(void); 208 char *channel_open_message(void); 209 int channel_find_open(void); 210 211 /* tcp forwarding */ 212 void channel_set_af(int af); 213 void channel_permit_all_opens(void); 214 void channel_add_permitted_opens(char *, int); 215 void channel_clear_permitted_opens(void); 216 void channel_input_port_forward_request(int, int); 217 int channel_connect_to(const char *, u_short); 218 int channel_connect_by_listen_address(u_short); 219 void channel_request_remote_forwarding(u_short, const char *, u_short); 220 int channel_setup_local_fwd_listener(u_short, const char *, u_short, int); 221 int channel_setup_remote_fwd_listener(const char *, u_short, int); 222 223 /* x11 forwarding */ 224 225 int x11_connect_display(void); 226 int x11_create_display_inet(int, int, int, u_int *); 227 void x11_input_open(int, u_int32_t, void *); 228 void x11_request_forwarding_with_spoofing(int, const char *, const char *); 229 void deny_input_open(int, u_int32_t, void *); 230 231 /* agent forwarding */ 232 233 void auth_request_forwarding(void); 234 void auth_input_open_request(int, u_int32_t, void *); 235 236 /* channel close */ 237 238 int chan_is_dead(Channel *, int); 239 void chan_mark_dead(Channel *); 240 241 /* channel events */ 242 243 void chan_rcvd_oclose(Channel *); 244 void chan_read_failed(Channel *); 245 void chan_ibuf_empty(Channel *); 246 247 void chan_rcvd_ieof(Channel *); 248 void chan_write_failed(Channel *); 249 void chan_obuf_empty(Channel *); 250 251 #ifdef __cplusplus 252 } 253 #endif 254 255 #endif /* _CHANNELS_H */ 256