1 /* 2 * Author: Tatu Ylonen <ylo@cs.hut.fi> 3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland 4 * All rights reserved 5 * 6 * As far as I am concerned, the code I have written for this software 7 * can be used freely for any purpose. Any derived versions of this 8 * software must be clearly marked as such, and if the derived work is 9 * incompatible with the protocol description in the RFC file, it must be 10 * called by a name other than "ssh" or "Secure Shell". 11 */ 12 /* 13 * Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved. 14 * 15 * Redistribution and use in source and binary forms, with or without 16 * modification, are permitted provided that the following conditions 17 * are met: 18 * 1. Redistributions of source code must retain the above copyright 19 * notice, this list of conditions and the following disclaimer. 20 * 2. Redistributions in binary form must reproduce the above copyright 21 * notice, this list of conditions and the following disclaimer in the 22 * documentation and/or other materials provided with the distribution. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 28 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 29 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 30 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 31 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 32 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 33 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 /* RCSID("$OpenBSD: channels.h,v 1.56 2001/12/28 15:06:00 markus Exp $"); */ 36 37 #ifndef CHANNEL_H 38 #define CHANNEL_H 39 40 #include "buffer.h" 41 42 /* Definitions for channel types. */ 43 #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */ 44 #define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */ 45 #define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */ 46 #define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */ 47 #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */ 48 #define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */ 49 #define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */ 50 #define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */ 51 #define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */ 52 #define SSH_CHANNEL_LARVAL 10 /* larval session */ 53 #define SSH_CHANNEL_RPORT_LISTENER 11 /* Listening to a R-style port */ 54 #define SSH_CHANNEL_CONNECTING 12 55 #define SSH_CHANNEL_DYNAMIC 13 56 #define SSH_CHANNEL_ZOMBIE 14 /* Almost dead. */ 57 #define SSH_CHANNEL_MAX_TYPE 15 58 59 #define SSH_CHANNEL_PATH_LEN 256 60 61 struct Channel; 62 typedef struct Channel Channel; 63 64 typedef void channel_callback_fn(int, void *); 65 typedef int channel_filter_fn(struct Channel *, char *, int); 66 67 struct Channel { 68 int type; /* channel type/state */ 69 int self; /* my own channel identifier */ 70 int remote_id; /* channel identifier for remote peer */ 71 int istate; /* input from channel (state of receive half) */ 72 int ostate; /* output to channel (state of transmit half) */ 73 int flags; /* close sent/rcvd */ 74 int rfd; /* read fd */ 75 int wfd; /* write fd */ 76 int efd; /* extended fd */ 77 int sock; /* sock fd */ 78 int isatty; /* rfd is a tty */ 79 int force_drain; /* force close on iEOF */ 80 int delayed; /* fdset hack */ 81 Buffer input; /* data read from socket, to be sent over 82 * encrypted connection */ 83 Buffer output; /* data received over encrypted connection for 84 * send on socket */ 85 Buffer extended; 86 char path[SSH_CHANNEL_PATH_LEN]; 87 /* path for unix domain sockets, or host name for forwards */ 88 int listening_port; /* port being listened for forwards */ 89 int host_port; /* remote port to connect for forwards */ 90 char *remote_name; /* remote hostname */ 91 92 int remote_window; 93 int remote_maxpacket; 94 int local_window; 95 int local_window_max; 96 int local_consumed; 97 int local_maxpacket; 98 int extended_usage; 99 int single_connection; 100 101 char *ctype; /* type */ 102 103 /* callback */ 104 channel_callback_fn *cb_fn; 105 void *cb_arg; 106 int cb_event; 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_WINDOW_DEFAULT (32*1024) 119 #define CHAN_SES_PACKET_DEFAULT (CHAN_SES_WINDOW_DEFAULT/2) 120 #define CHAN_TCP_WINDOW_DEFAULT (32*1024) 121 #define CHAN_TCP_PACKET_DEFAULT (CHAN_TCP_WINDOW_DEFAULT/2) 122 #define CHAN_X11_WINDOW_DEFAULT (4*1024) 123 #define CHAN_X11_PACKET_DEFAULT (CHAN_X11_WINDOW_DEFAULT/2) 124 125 /* possible input states */ 126 #define CHAN_INPUT_OPEN 0x01 127 #define CHAN_INPUT_WAIT_DRAIN 0x02 128 #define CHAN_INPUT_WAIT_OCLOSE 0x04 129 #define CHAN_INPUT_CLOSED 0x08 130 131 /* possible output states */ 132 #define CHAN_OUTPUT_OPEN 0x10 133 #define CHAN_OUTPUT_WAIT_DRAIN 0x20 134 #define CHAN_OUTPUT_WAIT_IEOF 0x40 135 #define CHAN_OUTPUT_CLOSED 0x80 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); 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(int, char *, int); 151 void channel_request_start(int, char *, int); 152 void channel_register_callback(int, int mtype, channel_callback_fn *, void *); 153 void channel_register_cleanup(int, channel_callback_fn *); 154 void channel_register_filter(int, channel_filter_fn *); 155 void channel_cancel_cleanup(int); 156 int channel_close_fd(int *); 157 158 /* protocol handler */ 159 160 void channel_input_channel_request(int, u_int32_t, void *); 161 void channel_input_close(int, u_int32_t, void *); 162 void channel_input_close_confirmation(int, u_int32_t, void *); 163 void channel_input_data(int, u_int32_t, void *); 164 void channel_input_extended_data(int, u_int32_t, void *); 165 void channel_input_ieof(int, u_int32_t, void *); 166 void channel_input_oclose(int, u_int32_t, void *); 167 void channel_input_open_confirmation(int, u_int32_t, void *); 168 void channel_input_open_failure(int, u_int32_t, void *); 169 void channel_input_port_open(int, u_int32_t, void *); 170 void channel_input_window_adjust(int, u_int32_t, void *); 171 172 /* file descriptor handling (read/write) */ 173 174 void channel_prepare_select(fd_set **, fd_set **, int *, int*, int); 175 void channel_after_select(fd_set *, fd_set *); 176 void channel_output_poll(void); 177 178 int channel_not_very_much_buffered_data(void); 179 void channel_close_all(void); 180 int channel_still_open(void); 181 char *channel_open_message(void); 182 int channel_find_open(void); 183 184 /* tcp forwarding */ 185 void channel_set_af(int af); 186 void channel_permit_all_opens(void); 187 void channel_add_permitted_opens(char *, int); 188 void channel_clear_permitted_opens(void); 189 void channel_input_port_forward_request(int, int); 190 int channel_connect_to(const char *, u_short); 191 int channel_connect_by_listen_address(u_short); 192 void channel_request_remote_forwarding(u_short, const char *, u_short); 193 int channel_request_local_forwarding(u_short, const char *, u_short, int); 194 int 195 channel_request_forwarding(const char *, u_short, const char *, u_short, int, 196 int); 197 198 /* x11 forwarding */ 199 200 int x11_connect_display(void); 201 int x11_create_display_inet(int, int, int); 202 void x11_input_open(int, u_int32_t, void *); 203 void x11_request_forwarding_with_spoofing(int, const char *, const char *); 204 void deny_input_open(int, u_int32_t, void *); 205 206 /* agent forwarding */ 207 208 void auth_request_forwarding(void); 209 char *auth_get_socket_name(void); 210 void auth_sock_cleanup_proc(void *); 211 int auth_input_request_forwarding(struct passwd *); 212 void auth_input_open_request(int, u_int32_t, void *); 213 214 /* channel close */ 215 216 int chan_is_dead(Channel *, int); 217 void chan_mark_dead(Channel *); 218 void chan_init_iostates(Channel *); 219 void chan_init(void); 220 221 typedef void chan_event_fn(Channel *); 222 223 /* for the input state */ 224 extern chan_event_fn *chan_rcvd_oclose; 225 extern chan_event_fn *chan_read_failed; 226 extern chan_event_fn *chan_ibuf_empty; 227 228 /* for the output state */ 229 extern chan_event_fn *chan_rcvd_ieof; 230 extern chan_event_fn *chan_write_failed; 231 extern chan_event_fn *chan_obuf_empty; 232 233 #endif 234