badvpn/flow/PacketProtoDecoder.h

97 lines
3.3 KiB
C

/**
* @file PacketProtoDecoder.h
* @author Ambroz Bizjak <ambrop7@gmail.com>
*
* @section LICENSE
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the author nor the
* names of its contributors may be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
* WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
* DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* @section DESCRIPTION
*
* Object which decodes a stream according to PacketProto.
*/
#ifndef BADVPN_FLOW_PACKETPROTODECODER_H
#define BADVPN_FLOW_PACKETPROTODECODER_H
#include <stdint.h>
#include <protocol/packetproto.h>
#include <misc/debug.h>
#include <base/DebugObject.h>
#include <flow/StreamRecvInterface.h>
#include <flow/PacketPassInterface.h>
/**
* Handler called when a protocol error occurs.
* When an error occurs, the decoder is reset to the initial state.
*
* @param user as in {@link PacketProtoDecoder_Init}
*/
typedef void (*PacketProtoDecoder_handler_error) (void *user);
typedef struct {
StreamRecvInterface *input;
PacketPassInterface *output;
void *user;
PacketProtoDecoder_handler_error handler_error;
int output_mtu;
int buf_size;
int buf_start;
int buf_used;
uint8_t *buf;
DebugObject d_obj;
} PacketProtoDecoder;
/**
* Initializes the object.
*
* @param enc the object
* @param input input interface. The decoder will accept packets with payload size up to its MTU
* (but the payload can never be more than PACKETPROTO_MAXPAYLOAD).
* @param output output interface
* @param pg pending group
* @param user argument to handlers
* @param handler_error error handler
* @return 1 on success, 0 on failure
*/
int PacketProtoDecoder_Init (PacketProtoDecoder *enc, StreamRecvInterface *input, PacketPassInterface *output, BPendingGroup *pg, void *user, PacketProtoDecoder_handler_error handler_error) WARN_UNUSED;
/**
* Frees the object.
*
* @param enc the object
*/
void PacketProtoDecoder_Free (PacketProtoDecoder *enc);
/**
* Clears the internal buffer.
* The next data received from the input will be treated as a new
* PacketProto stream.
*
* @param enc the object
*/
void PacketProtoDecoder_Reset (PacketProtoDecoder *enc);
#endif