| /* |
| * Dropbear - a SSH2 server |
| * |
| * Copyright (c) 2002,2003 Matt Johnston |
| * All rights reserved. |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining a copy |
| * of this software and associated documentation files (the "Software"), to deal |
| * in the Software without restriction, including without limitation the rights |
| * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell |
| * copies of the Software, and to permit persons to whom the Software is |
| * furnished to do so, subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be included in |
| * all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
| * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
| * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
| * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
| * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, |
| * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE |
| * SOFTWARE. */ |
| |
| #ifndef DROPBEAR_CHANNEL_H_ |
| #define DROPBEAR_CHANNEL_H_ |
| |
| #include "includes.h" |
| #include "buffer.h" |
| #include "circbuffer.h" |
| |
| #define SSH_OPEN_ADMINISTRATIVELY_PROHIBITED 1 |
| #define SSH_OPEN_CONNECT_FAILED 2 |
| #define SSH_OPEN_UNKNOWN_CHANNEL_TYPE 3 |
| #define SSH_OPEN_RESOURCE_SHORTAGE 4 |
| |
| /* Not a real type */ |
| #define SSH_OPEN_IN_PROGRESS 99 |
| |
| #define CHAN_EXTEND_SIZE 3 /* how many extra slots to add when we need more */ |
| |
| struct ChanType; |
| |
| enum dropbear_channel_prio { |
| DROPBEAR_CHANNEL_PRIO_INTERACTIVE, /* pty shell, x11 */ |
| DROPBEAR_CHANNEL_PRIO_UNKNOWABLE, /* tcp - can't know what's being forwarded */ |
| DROPBEAR_CHANNEL_PRIO_BULK, /* the rest - probably scp or something */ |
| DROPBEAR_CHANNEL_PRIO_EARLY, /* channel is still being set up */ |
| }; |
| |
| struct Channel { |
| |
| unsigned int index; /* the local channel index */ |
| unsigned int remotechan; |
| unsigned int recvwindow, transwindow; |
| unsigned int recvdonelen; |
| unsigned int recvmaxpacket, transmaxpacket; |
| void* typedata; /* a pointer to type specific data */ |
| int writefd; /* read from wire, written to insecure side */ |
| int readfd; /* read from insecure side, written to wire */ |
| int errfd; /* used like writefd or readfd, depending if it's client or server. |
| Doesn't exactly belong here, but is cleaner here */ |
| circbuffer *writebuf; /* data from the wire, for local consumption. Can be |
| initially NULL */ |
| circbuffer *extrabuf; /* extended-data for the program - used like writebuf |
| but for stderr */ |
| |
| /* whether close/eof messages have been exchanged */ |
| int sent_close, recv_close; |
| int recv_eof, sent_eof; |
| |
| /* Set after running the ChanType-specific close hander |
| * to ensure we don't run it twice (nor type->checkclose()). */ |
| int close_handler_done; |
| |
| struct dropbear_progress_connection *conn_pending; |
| int initconn; /* used for TCP forwarding, whether the channel has been |
| fully initialised */ |
| |
| int await_open; /* flag indicating whether we've sent an open request |
| for this channel (and are awaiting a confirmation |
| or failure). */ |
| |
| int flushing; |
| |
| /* Used by client chansession to handle ~ escaping, NULL ignored otherwise */ |
| void (*read_mangler)(struct Channel*, unsigned char* bytes, int *len); |
| |
| const struct ChanType* type; |
| |
| enum dropbear_channel_prio prio; |
| }; |
| |
| struct ChanType { |
| |
| int sepfds; /* Whether this channel has separate pipes for in/out or not */ |
| char *name; |
| int (*inithandler)(struct Channel*); |
| int (*check_close)(struct Channel*); |
| void (*reqhandler)(struct Channel*); |
| void (*closehandler)(struct Channel*); |
| }; |
| |
| /* Callback for connect_remote */ |
| void channel_connect_done(int result, int sock, void* user_data, const char* errstring); |
| |
| void chaninitialise(const struct ChanType *chantypes[]); |
| void chancleanup(); |
| void setchannelfds(fd_set *readfds, fd_set *writefds, int allow_reads); |
| void channelio(fd_set *readfd, fd_set *writefd); |
| struct Channel* getchannel(); |
| /* Returns an arbitrary channel that is in a ready state - not |
| being initialised and no EOF in either direction. NULL if none. */ |
| struct Channel* get_any_ready_channel(); |
| |
| void recv_msg_channel_open(); |
| void recv_msg_channel_request(); |
| void send_msg_channel_failure(struct Channel *channel); |
| void send_msg_channel_success(struct Channel *channel); |
| void recv_msg_channel_data(); |
| void recv_msg_channel_extended_data(); |
| void recv_msg_channel_window_adjust(); |
| void recv_msg_channel_close(); |
| void recv_msg_channel_eof(); |
| |
| void common_recv_msg_channel_data(struct Channel *channel, int fd, |
| circbuffer * buf); |
| |
| #ifdef DROPBEAR_CLIENT |
| extern const struct ChanType clichansess; |
| #endif |
| |
| #if defined(USING_LISTENERS) || defined(DROPBEAR_CLIENT) |
| int send_msg_channel_open_init(int fd, const struct ChanType *type); |
| void recv_msg_channel_open_confirmation(); |
| void recv_msg_channel_open_failure(); |
| #endif |
| void start_send_channel_request(struct Channel *channel, char *type); |
| |
| void send_msg_request_success(); |
| void send_msg_request_failure(); |
| |
| |
| #endif /* DROPBEAR_CHANNEL_H_ */ |