1 /* $OpenBSD: channels.h,v 1.70 2002/06/24 14:33:27 markus Exp $ */ 2 /* $FreeBSD: src/crypto/openssh/channels.h,v 1.1.1.1.2.7 2003/02/03 17:31:06 des Exp $ */ 3 4 /* 5 * Author: Tatu Ylonen <ylo@cs.hut.fi> 6 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 7 * All rights reserved 8 * 9 * As far as I am concerned, the code I have written for this software 10 * can be used freely for any purpose. Any derived versions of this 11 * software must be clearly marked as such, and if the derived work is 12 * incompatible with the protocol description in the RFC file, it must be 13 * called by a name other than "ssh" or "Secure Shell". 14 */ 15 /* 16 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. 17 * 18 * Redistribution and use in source and binary forms, with or without 19 * modification, are permitted provided that the following conditions 20 * are met: 21 * 1. Redistributions of source code must retain the above copyright 22 * notice, this list of conditions and the following disclaimer. 23 * 2. Redistributions in binary form must reproduce the above copyright 24 * notice, this list of conditions and the following disclaimer in the 25 * documentation and/or other materials provided with the distribution. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 28 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 29 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 30 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 31 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 32 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 33 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 34 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 35 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 36 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 37 */ 38 39 #ifndef CHANNEL_H 40 #define CHANNEL_H 41 42 #include "buffer.h" 43 44 /* Definitions for channel types. */ 45 #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */ 46 #define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */ 47 #define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */ 48 #define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */ 49 #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */ 50 #define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */ 51 #define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */ 52 #define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */ 53 #define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */ 54 #define SSH_CHANNEL_LARVAL 10 /* larval session */ 55 #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */ 56 #define SSH_CHANNEL_CONNECTING 12 57 #define SSH_CHANNEL_DYNAMIC 13 58 #define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */ 59 #define SSH_CHANNEL_MAX_TYPE 15 60 61 #define SSH_CHANNEL_PATH_LEN 256 62 63 struct Channel; 64 typedef struct Channel Channel; 65 66 typedef void channel_callback_fn(int, void *); 67 typedef int channel_filter_fn(struct Channel *, char *, int); 68 69 struct Channel { 70 int type; /* channel type/state */ 71 int self; /* my own channel identifier */ 72 int remote_id; /* channel identifier for remote peer */ 73 u_int istate; /* input from channel (state of receive half) */ 74 u_int ostate; /* output to channel (state of transmit half) */ 75 int flags; /* close sent/rcvd */ 76 int rfd; /* read fd */ 77 int wfd; /* write fd */ 78 int efd; /* extended fd */ 79 int sock; /* sock fd */ 80 int isatty; /* rfd is a tty */ 81 int wfd_isatty; /* wfd is a tty */ 82 int force_drain; /* force close on iEOF */ 83 int delayed; /* fdset hack */ 84 Buffer input; /* data read from socket, to be sent over 85 * encrypted connection */ 86 Buffer output; /* data received over encrypted connection for 87 * send on socket */ 88 Buffer extended; 89 char path[SSH_CHANNEL_PATH_LEN]; 90 /* path for unix domain sockets, or host name for forwards */ 91 int listening_port; /* port being listened for forwards */ 92 int host_port; /* remote port to connect for forwards */ 93 char *remote_name; /* remote hostname */ 94 95 u_int remote_window; 96 u_int remote_maxpacket; 97 u_int local_window; 98 u_int local_window_max; 99 u_int local_consumed; 100 u_int local_maxpacket; 101 int extended_usage; 102 int single_connection; 103 104 char *ctype; /* type */ 105 106 /* callback */ 107 channel_callback_fn *confirm; 108 channel_callback_fn *detach_user; 109 110 /* filter */ 111 channel_filter_fn *input_filter; 112 }; 113 114 #define CHAN_EXTENDED_IGNORE 0 115 #define CHAN_EXTENDED_READ 1 116 #define CHAN_EXTENDED_WRITE 2 117 118 /* default window/packet sizes for tcp/x11-fwd-channel */ 119 #define CHAN_SES_PACKET_DEFAULT (32*1024) 120 #define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT) 121 #define CHAN_TCP_PACKET_DEFAULT (32*1024) 122 #define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT) 123 #define CHAN_X11_PACKET_DEFAULT (16*1024) 124 #define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT) 125 126 /* possible input states */ 127 #define CHAN_INPUT_OPEN 0 128 #define CHAN_INPUT_WAIT_DRAIN 1 129 #define CHAN_INPUT_WAIT_OCLOSE 2 130 #define CHAN_INPUT_CLOSED 3 131 132 /* possible output states */ 133 #define CHAN_OUTPUT_OPEN 0 134 #define CHAN_OUTPUT_WAIT_DRAIN 1 135 #define CHAN_OUTPUT_WAIT_IEOF 2 136 #define CHAN_OUTPUT_CLOSED 3 137 138 #define CHAN_CLOSE_SENT 0x01 139 #define CHAN_CLOSE_RCVD 0x02 140 #define CHAN_EOF_SENT 0x04 141 #define CHAN_EOF_RCVD 0x08 142 143 /* check whether 'efd' is still in use */ 144 #define CHANNEL_EFD_INPUT_ACTIVE(c) \ 145 (compat20 && c->extended_usage == CHAN_EXTENDED_READ && \ 146 (c->efd != -1 || \ 147 buffer_len(&c->extended) > 0)) 148 #define CHANNEL_EFD_OUTPUT_ACTIVE(c) \ 149 (compat20 && c->extended_usage == CHAN_EXTENDED_WRITE && \ 150 ((c->efd != -1 && !(c->flags & (CHAN_EOF_RCVD|CHAN_CLOSE_RCVD))) || \ 151 buffer_len(&c->extended) > 0)) 152 153 /* channel management */ 154 155 Channel *channel_lookup(int); 156 Channel *channel_new(char *, int, int, int, int, u_int, u_int, int, char *, int); 157 void channel_set_fds(int, int, int, int, int, int, u_int); 158 void channel_free(Channel *); 159 void channel_free_all(void); 160 void channel_stop_listening(void); 161 162 void channel_send_open(int); 163 void channel_request_start(int, char *, int); 164 void channel_register_cleanup(int, channel_callback_fn *); 165 void channel_register_confirm(int, channel_callback_fn *); 166 void channel_register_filter(int, channel_filter_fn *); 167 void channel_cancel_cleanup(int); 168 int channel_close_fd(int *); 169 170 /* protocol handler */ 171 172 void channel_input_close(int, u_int32_t, void *); 173 void channel_input_close_confirmation(int, u_int32_t, void *); 174 void channel_input_data(int, u_int32_t, void *); 175 void channel_input_extended_data(int, u_int32_t, void *); 176 void channel_input_ieof(int, u_int32_t, void *); 177 void channel_input_oclose(int, u_int32_t, void *); 178 void channel_input_open_confirmation(int, u_int32_t, void *); 179 void channel_input_open_failure(int, u_int32_t, void *); 180 void channel_input_port_open(int, u_int32_t, void *); 181 void channel_input_window_adjust(int, u_int32_t, void *); 182 183 /* file descriptor handling (read/write) */ 184 185 void channel_prepare_select(fd_set **, fd_set **, int *, int*, int); 186 void channel_after_select(fd_set *, fd_set *); 187 void channel_output_poll(void); 188 189 int channel_not_very_much_buffered_data(void); 190 void channel_close_all(void); 191 int channel_still_open(void); 192 char *channel_open_message(void); 193 int channel_find_open(void); 194 195 /* tcp forwarding */ 196 void channel_set_af(int af); 197 void channel_permit_all_opens(void); 198 void channel_add_permitted_opens(char *, int); 199 void channel_clear_permitted_opens(void); 200 void channel_input_port_forward_request(int, int); 201 int channel_connect_to(const char *, u_short); 202 int channel_connect_by_listen_address(u_short); 203 void channel_request_remote_forwarding(u_short, const char *, u_short); 204 int channel_setup_local_fwd_listener(u_short, const char *, u_short, int); 205 int channel_setup_remote_fwd_listener(const char *, u_short, int); 206 207 /* x11 forwarding */ 208 209 int x11_connect_display(void); 210 int x11_create_display_inet(int, int, int, u_int *); 211 void x11_input_open(int, u_int32_t, void *); 212 void x11_request_forwarding_with_spoofing(int, const char *, const char *); 213 void deny_input_open(int, u_int32_t, void *); 214 215 /* agent forwarding */ 216 217 void auth_request_forwarding(void); 218 void auth_input_open_request(int, u_int32_t, void *); 219 220 /* channel close */ 221 222 int chan_is_dead(Channel *, int); 223 void chan_mark_dead(Channel *); 224 225 /* channel events */ 226 227 void chan_rcvd_oclose(Channel *); 228 void chan_read_failed(Channel *); 229 void chan_ibuf_empty(Channel *); 230 231 void chan_rcvd_ieof(Channel *); 232 void chan_write_failed(Channel *); 233 void chan_obuf_empty(Channel *); 234 235 #endif 236