public static Packet ParsePacket(Byte[] data, byte[] crypto_key)
{
Packet packet = new Packet();
BinaryReader reader = new BinaryReader(new MemoryStream(data));
packet.head = reader.ReadUInt32();
var packet_size = packet.AllSize();
var checksum_offset = HEAD_SIZE;
if (packet.CheckMask(NetHelper.HEAD_CRY_MASK) && packet.AllSize() > HEAD_SIZE)
{
//byte[] decryptData = AESEncryptionUtility.Decrypt(reader.ReadBytes(packet_size - (int)HEAD_SIZE), AESEncryptionUtility.defaultKey, AESEncryptionUtility.commonIV);
var decryptData = reader.ReadBytes(packet_size - (int)HEAD_SIZE);
RC4Utility.XORKeyStream(ref decryptData, crypto_key);
reader = new BinaryReader(new MemoryStream(decryptData));
data = decryptData;
// 前面已经过滤了headmask 所以要回退4个字节
checksum_offset -= HEAD_SIZE;
}
if (packet.CheckMask(NetHelper.HEAD_CHK_MASK))
{
packet.checksum = reader.ReadUInt32();
// 自己不算内
checksum_offset += 4;
UInt32 checksum = NetHelper.ComputeAdler32(data, (int)checksum_offset, packet_size - (int)checksum_offset);
if (packet.checksum != checksum)
{
throw new Exception("CheckSum Fail. " + packet.checksum + " != " + checksum);
}
}
if (packet.CheckMask(NetHelper.HEAD_SEQ_MASK))
{
packet.sequence = reader.ReadUInt32();
}
if (packet.CheckMask(NetHelper.HEAD_REQ_MASK))
{
packet.requestId = reader.ReadUInt32();
}
if (packet.CheckMask(NetHelper.HEAD_RPC_MASK))
{
packet.rpcId = reader.ReadUInt32();
}
if (packet.CheckMask(NetHelper.HEAD_MSG_MASK))
{
packet.opcode = reader.ReadUInt32();
packet.message = reader.ReadBytes((int)packet.MsgSize());
}
return(packet);
}
public byte[] Encrypt(byte[] toEncrypt)
{
return(RC4Utility.Encrypt(toEncrypt, this.mkey));
}
public byte[] Decrypt(byte[] toDecrypt)
{
return(RC4Utility.Decrypt(toDecrypt, this.mkey));
}
public RC4Crypto(int seed)
{
mkey = RC4Utility.GenRC4SecretKey(seed);
Console.WriteLine("RC4Crypto: {0}", System.Text.Encoding.Default.GetString(mkey));
}
