diff options
Diffstat (limited to 'channel.h')
| -rw-r--r-- | channel.h | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/channel.h b/channel.h new file mode 100644 index 0000000..7030a0f --- /dev/null +++ b/channel.h @@ -0,0 +1,135 @@ +/* + * 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 _CHANNEL_H_ +#define _CHANNEL_H_ + +#include "includes.h" +#include "buffer.h" +#include "circbuffer.h" + +/* channel->type values */ +#define CHANNEL_ID_NONE 0 +#define CHANNEL_ID_SESSION 1 +#define CHANNEL_ID_X11 2 +#define CHANNEL_ID_AGENT 3 +#define CHANNEL_ID_TCPDIRECT 4 +#define CHANNEL_ID_TCPFORWARDED 5 + +#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 MAX_CHANNELS 100 /* simple mem restriction, includes each tcp/x11 + connection, so can't be _too_ small */ + +#define CHAN_EXTEND_SIZE 3 /* how many extra slots to add when we need more */ + +#define RECV_MAXWINDOW 8000 /* tweak */ +#define RECV_WINDOWEXTEND 1000 /* We send a "window extend" every + RECV_WINDOWEXTEND bytes */ +#define RECV_MAXPACKET RECV_MAXWINDOW /* tweak */ + +struct ChanType; + +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 size, 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 */ + circbuffer *extrabuf; /* extended-data for the program - used like writebuf + but for stderr */ + + int sentclosed, recvclosed; + + /* this is set when we receive/send a channel eof packet */ + int recveof, senteof; + + 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). */ + + const struct ChanType* type; + +}; + +struct ChanType { + + int sepfds; /* Whether this channel has seperate pipes for in/out or not */ + char *name; + int (*inithandler)(struct Channel*); + int (*checkclose)(struct Channel*); + void (*reqhandler)(struct Channel*); + void (*closehandler)(struct Channel*); + +}; + +void chaninitialise(const struct ChanType *chantypes[]); +void chancleanup(); +void setchannelfds(fd_set *readfd, fd_set *writefd); +void channelio(fd_set *readfd, fd_set *writefd); +struct Channel* getchannel(); +struct Channel* newchannel(unsigned int remotechan, + const struct ChanType *type, + unsigned int transwindow, unsigned int transmaxpacket); + +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 + +#endif /* _CHANNEL_H_ */ |