Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 1 | /* RCSID("$Id: channels.h,v 1.5 2000/04/01 01:09:23 damien Exp $"); */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 2 | |
| 3 | #ifndef CHANNELS_H |
| 4 | #define CHANNELS_H |
| 5 | |
| 6 | /* Definitions for channel types. */ |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 7 | #define SSH_CHANNEL_FREE 0 /* This channel is free (unused). */ |
| 8 | #define SSH_CHANNEL_X11_LISTENER 1 /* Listening for inet X11 conn. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 9 | #define SSH_CHANNEL_PORT_LISTENER 2 /* Listening on a port. */ |
| 10 | #define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */ |
| 11 | #define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */ |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 12 | #define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */ |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 13 | #define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */ |
| 14 | #define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */ |
| 15 | #define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */ |
| 16 | #define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */ |
| 17 | #define SSH_CHANNEL_LARVAL 10 /* larval session */ |
| 18 | #define SSH_CHANNEL_MAX_TYPE 11 |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 19 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 20 | /* |
| 21 | * Data structure for channel data. This is iniailized in channel_allocate |
| 22 | * and cleared in channel_free. |
| 23 | */ |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 24 | typedef void channel_callback_fn(int id, void *arg); |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 25 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 26 | typedef struct Channel { |
| 27 | int type; /* channel type/state */ |
| 28 | int self; /* my own channel identifier */ |
| 29 | int remote_id; /* channel identifier for remote peer */ |
| 30 | /* peer can be reached over encrypted connection, via packet-sent */ |
| 31 | int istate; /* input from channel (state of receive half) */ |
| 32 | int ostate; /* output to channel (state of transmit half) */ |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 33 | int rfd; /* read fd */ |
| 34 | int wfd; /* write fd */ |
| 35 | int efd; /* extended fd */ |
| 36 | int sock; /* sock fd */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 37 | Buffer input; /* data read from socket, to be sent over |
| 38 | * encrypted connection */ |
| 39 | Buffer output; /* data received over encrypted connection for |
| 40 | * send on socket */ |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 41 | Buffer extended; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 42 | char path[200]; /* path for unix domain sockets, or host name |
| 43 | * for forwards */ |
| 44 | int listening_port; /* port being listened for forwards */ |
| 45 | int host_port; /* remote port to connect for forwards */ |
| 46 | char *remote_name; /* remote hostname */ |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 47 | |
| 48 | int remote_window; |
| 49 | int remote_maxpacket; |
| 50 | int local_window; |
| 51 | int local_window_max; |
| 52 | int local_consumed; |
| 53 | int local_maxpacket; |
| 54 | int extended_usage; |
| 55 | |
| 56 | char *ctype; /* type */ |
| 57 | |
| 58 | // callback |
| 59 | channel_callback_fn *cb_fn; |
| 60 | void *cb_arg; |
| 61 | int cb_event; |
| 62 | channel_callback_fn *dettach_user; |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 63 | } Channel; |
Damien Miller | b38eff8 | 2000-04-01 11:09:21 +1000 | [diff] [blame^] | 64 | |
| 65 | #define CHAN_EXTENDED_IGNORE 0 |
| 66 | #define CHAN_EXTENDED_READ 1 |
| 67 | #define CHAN_EXTENDED_WRITE 2 |
| 68 | |
| 69 | void channel_open(int id); |
| 70 | Channel *channel_lookup(int id); |
| 71 | |
| 72 | int |
| 73 | channel_new(char *ctype, int type, int rfd, int wfd, int efd, |
| 74 | int window, int maxpack, int extended_usage, char *remote_name); |
| 75 | |
| 76 | void channel_input_close(int type, int plen); |
| 77 | void channel_input_close_confirmation(int type, int plen); |
| 78 | void channel_input_data(int type, int plen); |
| 79 | void channel_input_ieof(int type, int plen); |
| 80 | void channel_input_oclose(int type, int plen); |
| 81 | void channel_input_open_confirmation(int type, int plen); |
| 82 | void channel_input_open_failure(int type, int plen); |
| 83 | void channel_input_port_open(int type, int plen); |
| 84 | void channel_input_open(int type, int plen); |
| 85 | |
| 86 | /* Sets specific protocol options. */ |
| 87 | void channel_set_options(int hostname_in_open); |
| 88 | |
| 89 | /* |
| 90 | * Allocate a new channel object and set its type and socket. Remote_name |
| 91 | * must have been allocated with xmalloc; this will free it when the channel |
| 92 | * is freed. |
| 93 | */ |
| 94 | int channel_allocate(int type, int sock, char *remote_name); |
| 95 | |
| 96 | /* Free the channel and close its socket. */ |
| 97 | void channel_free(int channel); |
| 98 | |
| 99 | /* Add any bits relevant to channels in select bitmasks. */ |
| 100 | void channel_prepare_select(fd_set * readset, fd_set * writeset); |
| 101 | |
| 102 | /* |
| 103 | * After select, perform any appropriate operations for channels which have |
| 104 | * events pending. |
| 105 | */ |
| 106 | void channel_after_select(fd_set * readset, fd_set * writeset); |
| 107 | |
| 108 | /* If there is data to send to the connection, send some of it now. */ |
| 109 | void channel_output_poll(void); |
| 110 | |
| 111 | /* Returns true if no channel has too much buffered data. */ |
| 112 | int channel_not_very_much_buffered_data(void); |
| 113 | |
| 114 | /* This closes any sockets that are listening for connections; this removes |
| 115 | any unix domain sockets. */ |
| 116 | void channel_stop_listening(void); |
| 117 | |
| 118 | /* |
| 119 | * Closes the sockets of all channels. This is used to close extra file |
| 120 | * descriptors after a fork. |
| 121 | */ |
| 122 | void channel_close_all(void); |
| 123 | |
| 124 | /* Returns the maximum file descriptor number used by the channels. */ |
| 125 | int channel_max_fd(void); |
| 126 | |
| 127 | /* Returns true if there is still an open channel over the connection. */ |
| 128 | int channel_still_open(void); |
| 129 | |
| 130 | /* |
| 131 | * Returns a string containing a list of all open channels. The list is |
| 132 | * suitable for displaying to the user. It uses crlf instead of newlines. |
| 133 | * The caller should free the string with xfree. |
| 134 | */ |
| 135 | char *channel_open_message(void); |
| 136 | |
| 137 | /* |
| 138 | * Initiate forwarding of connections to local port "port" through the secure |
| 139 | * channel to host:port from remote side. This never returns if there was an |
| 140 | * error. |
| 141 | */ |
| 142 | void |
| 143 | channel_request_local_forwarding(u_short port, const char *host, |
| 144 | u_short remote_port, int gateway_ports); |
| 145 | |
| 146 | /* |
| 147 | * Initiate forwarding of connections to port "port" on remote host through |
| 148 | * the secure channel to host:port from local side. This never returns if |
| 149 | * there was an error. This registers that open requests for that port are |
| 150 | * permitted. |
| 151 | */ |
| 152 | void |
| 153 | channel_request_remote_forwarding(u_short port, const char *host, |
| 154 | u_short remote_port); |
| 155 | |
| 156 | /* |
| 157 | * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually |
| 158 | * called by the server, because the user could connect to any port anyway, |
| 159 | * and the server has no way to know but to trust the client anyway. |
| 160 | */ |
| 161 | void channel_permit_all_opens(void); |
| 162 | |
| 163 | /* |
| 164 | * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates |
| 165 | * listening for the port, and sends back a success reply (or disconnect |
| 166 | * message if there was an error). This never returns if there was an error. |
| 167 | */ |
| 168 | void channel_input_port_forward_request(int is_root); |
| 169 | |
| 170 | /* |
| 171 | * Creates a port for X11 connections, and starts listening for it. Returns |
| 172 | * the display name, or NULL if an error was encountered. |
| 173 | */ |
| 174 | char *x11_create_display(int screen); |
| 175 | |
| 176 | /* |
| 177 | * Creates an internet domain socket for listening for X11 connections. |
| 178 | * Returns a suitable value for the DISPLAY variable, or NULL if an error |
| 179 | * occurs. |
| 180 | */ |
| 181 | char *x11_create_display_inet(int screen, int x11_display_offset); |
| 182 | |
| 183 | /* |
| 184 | * This is called when SSH_SMSG_X11_OPEN is received. The packet contains |
| 185 | * the remote channel number. We should do whatever we want, and respond |
| 186 | * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE. |
| 187 | */ |
| 188 | void x11_input_open(int type, int plen); |
| 189 | |
| 190 | /* |
| 191 | * Requests forwarding of X11 connections. This should be called on the |
| 192 | * client only. |
| 193 | */ |
| 194 | void x11_request_forwarding(void); |
| 195 | |
| 196 | /* |
| 197 | * Requests forwarding for X11 connections, with authentication spoofing. |
| 198 | * This should be called in the client only. |
| 199 | */ |
| 200 | void x11_request_forwarding_with_spoofing(const char *proto, const char *data); |
| 201 | |
| 202 | /* Sends a message to the server to request authentication fd forwarding. */ |
| 203 | void auth_request_forwarding(void); |
| 204 | |
| 205 | /* |
| 206 | * Returns the name of the forwarded authentication socket. Returns NULL if |
| 207 | * there is no forwarded authentication socket. The returned value points to |
| 208 | * a static buffer. |
| 209 | */ |
| 210 | char *auth_get_socket_name(void); |
| 211 | |
| 212 | /* |
| 213 | * This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server. |
| 214 | * This starts forwarding authentication requests. |
| 215 | */ |
| 216 | void auth_input_request_forwarding(struct passwd * pw); |
| 217 | |
| 218 | /* This is called to process an SSH_SMSG_AGENT_OPEN message. */ |
| 219 | void auth_input_open_request(int type, int plen); |
| 220 | |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 221 | #endif |