1 /* $OpenBSD: channels.h,v 1.65 2002/03/04 17:27:39 stevesk Exp $ */ 2 /* $FreeBSD$ */ 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 force_drain; /* force close on iEOF */ 82 int delayed; /* fdset hack */ 83 Buffer input; /* data read from socket, to be sent over 84 * encrypted connection */ 85 Buffer output; /* data received over encrypted connection for 86 * send on socket */ 87 Buffer extended; 88 char path[SSH_CHANNEL_PATH_LEN]; 89 /* path for unix domain sockets, or host name for forwards */ 90 int listening_port; /* port being listened for forwards */ 91 int host_port; /* remote port to connect for forwards */ 92 char *remote_name; /* remote hostname */ 93 94 int remote_window; 95 int remote_maxpacket; 96 int local_window; 97 int local_window_max; 98 int local_consumed; 99 int local_maxpacket; 100 int extended_usage; 101 int single_connection; 102 103 char *ctype; /* type */ 104 105 /* callback */ 106 channel_callback_fn *confirm; 107 channel_callback_fn *detach_user; 108 109 /* filter */ 110 channel_filter_fn *input_filter; 111 }; 112 113 #define CHAN_EXTENDED_IGNORE 0 114 #define CHAN_EXTENDED_READ 1 115 #define CHAN_EXTENDED_WRITE 2 116 117 /* default window/packet sizes for tcp/x11-fwd-channel */ 118 #define CHAN_SES_PACKET_DEFAULT (32*1024) 119 #define CHAN_SES_WINDOW_DEFAULT (4*CHAN_SES_PACKET_DEFAULT) 120 #define CHAN_TCP_PACKET_DEFAULT (32*1024) 121 #define CHAN_TCP_WINDOW_DEFAULT (4*CHAN_TCP_PACKET_DEFAULT) 122 #define CHAN_X11_PACKET_DEFAULT (16*1024) 123 #define CHAN_X11_WINDOW_DEFAULT (4*CHAN_X11_PACKET_DEFAULT) 124 125 /* possible input states */ 126 #define CHAN_INPUT_OPEN 0 127 #define CHAN_INPUT_WAIT_DRAIN 1 128 #define CHAN_INPUT_WAIT_OCLOSE 2 129 #define CHAN_INPUT_CLOSED 3 130 131 /* possible output states */ 132 #define CHAN_OUTPUT_OPEN 0 133 #define CHAN_OUTPUT_WAIT_DRAIN 1 134 #define CHAN_OUTPUT_WAIT_IEOF 2 135 #define CHAN_OUTPUT_CLOSED 3 136 137 #define CHAN_CLOSE_SENT 0x01 138 #define CHAN_CLOSE_RCVD 0x02 139 140 /* channel management */ 141 142 Channel *channel_lookup(int); 143 Channel *channel_new(char *, int, int, int, int, int, int, int, char *, int); 144 void channel_set_fds(int, int, int, int, int, int, u_int); 145 void channel_free(Channel *); 146 void channel_free_all(void); 147 void channel_stop_listening(void); 148 149 void channel_send_open(int); 150 void channel_request_start(int, char *, int); 151 void channel_register_cleanup(int, channel_callback_fn *); 152 void channel_register_confirm(int, channel_callback_fn *); 153 void channel_register_filter(int, channel_filter_fn *); 154 void channel_cancel_cleanup(int); 155 int channel_close_fd(int *); 156 157 /* protocol handler */ 158 159 void channel_input_close(int, u_int32_t, void *); 160 void channel_input_close_confirmation(int, u_int32_t, void *); 161 void channel_input_data(int, u_int32_t, void *); 162 void channel_input_extended_data(int, u_int32_t, void *); 163 void channel_input_ieof(int, u_int32_t, void *); 164 void channel_input_oclose(int, u_int32_t, void *); 165 void channel_input_open_confirmation(int, u_int32_t, void *); 166 void channel_input_open_failure(int, u_int32_t, void *); 167 void channel_input_port_open(int, u_int32_t, void *); 168 void channel_input_window_adjust(int, u_int32_t, void *); 169 170 /* file descriptor handling (read/write) */ 171 172 void channel_prepare_select(fd_set **, fd_set **, int *, int*, int); 173 void channel_after_select(fd_set *, fd_set *); 174 void channel_output_poll(void); 175 176 int channel_not_very_much_buffered_data(void); 177 void channel_close_all(void); 178 int channel_still_open(void); 179 char *channel_open_message(void); 180 int channel_find_open(void); 181 182 /* tcp forwarding */ 183 void channel_set_af(int af); 184 void channel_permit_all_opens(void); 185 void channel_add_permitted_opens(char *, int); 186 void channel_clear_permitted_opens(void); 187 void channel_input_port_forward_request(int, int); 188 int channel_connect_to(const char *, u_short); 189 int channel_connect_by_listen_address(u_short); 190 void channel_request_remote_forwarding(u_short, const char *, u_short); 191 int channel_setup_local_fwd_listener(u_short, const char *, u_short, int); 192 int channel_setup_remote_fwd_listener(const char *, u_short, int); 193 194 /* x11 forwarding */ 195 196 int x11_connect_display(void); 197 int x11_create_display_inet(int, int, int); 198 void x11_input_open(int, u_int32_t, void *); 199 void x11_request_forwarding_with_spoofing(int, const char *, const char *); 200 void deny_input_open(int, u_int32_t, void *); 201 202 /* agent forwarding */ 203 204 void auth_request_forwarding(void); 205 char *auth_get_socket_name(void); 206 int auth_input_request_forwarding(struct passwd *); 207 void auth_input_open_request(int, u_int32_t, void *); 208 209 /* channel close */ 210 211 int chan_is_dead(Channel *, int); 212 void chan_mark_dead(Channel *); 213 214 /* channel events */ 215 216 void chan_rcvd_oclose(Channel *); 217 void chan_read_failed(Channel *); 218 void chan_ibuf_empty(Channel *); 219 220 void chan_rcvd_ieof(Channel *); 221 void chan_write_failed(Channel *); 222 void chan_obuf_empty(Channel *); 223 224 #endif 225