public override Result ModifySend(Packet packet, MemoryStream packetBuf, int packetStartPosition)
{
int BLOCK_SIZE = 16;
uint len = Protocol.GetMessageLength(packetBuf, packetStartPosition);
// 스트림에 패드 크기를 확보해 둔다. 아래 구현은 서버와 같다.
var padSize = BLOCK_SIZE - (len - Protocol.headerSize) % BLOCK_SIZE;
var pad = HexStringToBytes("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF");
packetBuf.Write(pad, 0, (int)padSize);
byte[] buf = packetBuf.GetBuffer();
// 해시 데이터 반영
sender.UpdateHash(buf, packetStartPosition + Protocol.headerSize, (int)(len - Protocol.headerSize));
byte[] encryptedData = sender.TransformFinalBlock(buf, packetStartPosition + Protocol.headerSize, (int)(len - Protocol.headerSize));
Buffer.BlockCopy(encryptedData, 0, buf, packetStartPosition + Protocol.headerSize, encryptedData.Length);
// 완료 처리
sender.Complete();
// 패킷 길이 변경
Protocol.SetMessageLength(packetBuf, packetStartPosition, (uint)(encryptedData.Length + Protocol.headerSize));
return(Result.Success());
}
public override Result ModifyRecv(Packet packet, MemoryStream packetBuf, int packetStartPosition)
{
uint len = Protocol.GetMessageLength(packetBuf, packetStartPosition);
// 서버 구현에 맞춤. 비어 있으면 해시 없음
if (len == Protocol.headerSize)
{
return(Result.Success());
}
var buf = packetBuf.GetBuffer();
byte[] hash = crc.ComputeHash(
buf,
packetStartPosition + Protocol.headerSize,
(int)(len - Protocol.headerSize - 4));
var crcIndex = packetStartPosition + (int)(len - 4);
bool equal = hash[0] == buf[crcIndex + 0] &&
hash[1] == buf[crcIndex + 1] &&
hash[2] == buf[crcIndex + 2] &&
hash[3] == buf[crcIndex + 3];
if (!equal)
{
return(Result.Fail(Result.Code.FailInvalidCrc));
}
Protocol.SetMessageLength(packetBuf, packetStartPosition, len - 4);
return(Result.Success());
}
public override Result ModifySend(Packet packet, MemoryStream packetBuf, int packetStartPosition)
{
uint len = Protocol.GetMessageLength(packetBuf, packetStartPosition);
packetBuf.WriteByte(sendSeq);
Protocol.SetMessageLength(packetBuf, packetStartPosition, len + 1);
IncSendSeq();
return(Result.Success());
}
public override Result ModifyRecv(Packet packet, MemoryStream packetBuf, int packetStartPosition)
{
uint len = Protocol.GetMessageLength(packetBuf, packetStartPosition);
byte[] buf = packetBuf.GetBuffer();
byte[] decryptedData = recevier.TransformFinalBlock(buf, packetStartPosition + Protocol.headerSize, (int)(len - Protocol.headerSize));
Buffer.BlockCopy(decryptedData, 0, buf, packetStartPosition + Protocol.headerSize, decryptedData.Length);
recevier.UpdateHash(decryptedData, 0, decryptedData.Length);
// 완료 처리
recevier.Complete();
// 패킷 길이 변경
Protocol.SetMessageLength(packetBuf, packetStartPosition, (uint)(decryptedData.Length + Protocol.headerSize));
return(Result.Success());
}
public override Result ModifyRecv(Packet packet, MemoryStream packetBuf, int packetStartPosition)
{
uint len = Protocol.GetMessageLength(packetBuf, packetStartPosition);
var buf = packetBuf.GetBuffer();
byte seq = buf[packetStartPosition + len - 1];
if (seq != recvSeq)
{
return(Result.Fail(Result.Code.FailInvalidRecvSequence));
}
Protocol.SetMessageLength(packetBuf, packetStartPosition, len - 1);
IncRecvSeq();
return(Result.Success());
}
public override Result ModifySend(Packet packet, MemoryStream packetBuf, int packetStartPosition)
{
uint len = Protocol.GetMessageLength(packetBuf, packetStartPosition);
// 서버 구현에 맞춤. 비어 있으면 해시 없음
if (len == Protocol.headerSize)
{
return(Result.Success());
}
var buf = packetBuf.GetBuffer();
byte[] hash = crc.ComputeHash(
buf,
packetStartPosition + Protocol.headerSize,
(int)(len - Protocol.headerSize));
packetBuf.Write(hash, 0, 4);
Protocol.SetMessageLength(packetBuf, packetStartPosition, len + 4);
return(Result.Success());
}
