public byte[] DecryptFRMPayload(byte[] key, UnconfirmedDataUp data)
{
var returnvalue = new byte[data.FRMPayload.Length];
int j = 0;
byte i = 1;
while (j < data.FRMPayload.Length)
{
var partsize = data.FRMPayload.Length - (j * 16) >= 16 ? 16 : data.FRMPayload.Length - (j * 16);
var part = new byte[partsize];
Buffer.BlockCopy(data.FRMPayload, j, part, 0, partsize);
var buf = new byte[16];
buf[0] = 0x01;
buf[5] = 0x00;
Buffer.BlockCopy(MarshalDevAddr(data.Fhdr.DevAddr), 0, buf, 6, 4);
Buffer.BlockCopy(BitConverter.GetBytes(Convert.ToUInt32(data.Fhdr.FCnt)), 0, buf, 10, 4);
buf[15] = i;
var key2 = Encrypt(buf, key);
for (int x = 0; x < partsize; x++)
{
returnvalue[(j * 16) + x] = (byte)(part[x] ^ key2[x]);
}
j += 16;
}
return(returnvalue);
}
public UnconfirmedDataUp UnmarshalUnconfirmedDataUp(byte[] message)
{
var returnvalue = new UnconfirmedDataUp();
returnvalue.Mhdr = UnmarshalMhdr(message[0]);
var fctrl = UnmarshalFCtrlUplink(message[5]);
var fhdr = new byte[7 + fctrl.FOptsLen];
Buffer.BlockCopy(message, 1, fhdr, 0, 7 + fctrl.FOptsLen);
returnvalue.Fhdr = UnmarshalFhdrUplink(fhdr, fctrl);
if (message.Length - 1 /*mhdr*/ - 7 /*fhdr*/ - fctrl.FOptsLen - 4 /*mic*/ > 0)
{
returnvalue.FPort = message[1 + 7 + fctrl.FOptsLen];
var frmpayloadsize = message.Length - 1 /*mhdr*/ - 7 /*fhdr*/ - fctrl.FOptsLen - 1 /*fport*/ - 4 /*mic*/;
returnvalue.FRMPayload = new byte[frmpayloadsize];
Buffer.BlockCopy(message, 1 + 7 + fctrl.FOptsLen + 1, returnvalue.FRMPayload, 0, frmpayloadsize);
}
returnvalue.Mic = new byte[4];
Buffer.BlockCopy(message, message.Length - 4, returnvalue.Mic, 0, 4);
return(returnvalue);
}
