public TPDUConnection(byte[] packet)
{
int pos;
int li = packet[0];
TPDU.TPDU_TYPES type = (TPDU.TPDU_TYPES)(packet[1] >> 4);
if ((type != TPDU.TPDU_TYPES.CR) && (type != TPDU.TPDU_TYPES.CC))
{
throw new ApplicationException("TPDU: This can only handle CC/CR TDPUs");
}
if (BitConverter.IsLittleEndian)
{
DstRef = ByteConvert.DoReverseEndian(BitConverter.ToUInt16(packet, 2));
SrcRef = ByteConvert.DoReverseEndian(BitConverter.ToUInt16(packet, 4));
}
else
{
DstRef = BitConverter.ToUInt16(packet, 2);
SrcRef = BitConverter.ToUInt16(packet, 4);
}
ClassOption = ((packet[6] & 0xf0) >> 4);
if (ClassOption > 4)
{
throw new Exception("TPDU: Class option number not allowed.");
}
pos = 7;
// read variable part
Varpart = new ArrayList();
try
{
while (pos < li)
{
VarParam vp = new VarParam();
vp.code = packet[pos];
pos += 1;
vp.length = packet[pos];
pos += 1;
vp.value = new byte[vp.length];
Array.Copy(packet, pos, vp.value, 0, vp.length);
pos += vp.length;
Varpart.Add(vp);
}
}
catch (Exception)
{
throw new Exception("TPDU: Error parsing variable part of CR/CC PDU.");
}
}
public TPDUData(byte[] packet, int packetLen)
{
if (packetLen < DT_HLEN)
{
throw new Exception("TPDU: DT packet size lower than minimum of 3 bytes.");
}
int li = packet[0];
TPDU.TPDU_TYPES type = (TPDU.TPDU_TYPES)(packet[1] >> 4);
if (type != TPDU.TPDU_TYPES.DT)
{
throw new ApplicationException("TPDU: This can only handle DT TDPUs");
}
if (li != HLEN_LI_NORMAL_DT_CLASS_01)
{
throw new Exception("TPDU: Header length indicator in DT packet other than 2 in class 0/1 PDUs are not allowed.");
}
TPDUNr = (packet[2] & 0x7f);
if ((packet[2] & 0x80) != 0)
{
EOT = true;
}
else
{
EOT = false;
}
PayloadLength = packetLen - DT_HLEN;
Payload = new byte[PayloadLength];
Array.Copy(packet, DT_HLEN, Payload, 0, PayloadLength);
}
