public static STUNHeader ParseSTUNHeader(byte[] buffer)
{
if ((buffer[0] & STUN_INITIAL_BYTE_MASK) != 0)
{
throw new ApplicationException("The STUN header did not begin with 0x00.");
}
if (buffer != null && buffer.Length > 0 && buffer.Length >= STUN_HEADER_LENGTH)
{
STUNHeader stunHeader = new STUNHeader();
UInt16 stunTypeValue = BitConverter.ToUInt16(buffer, 0);
UInt16 stunMessageLength = BitConverter.ToUInt16(buffer, 2);
if (BitConverter.IsLittleEndian)
{
stunTypeValue = NetConvert.DoReverseEndian(stunTypeValue);
stunMessageLength = NetConvert.DoReverseEndian(stunMessageLength);
}
stunHeader.MessageType = STUNMessageTypes.GetSTUNMessageTypeForId(stunTypeValue);
stunHeader.MessageLength = stunMessageLength;
Buffer.BlockCopy(buffer, 8, stunHeader.TransactionId, 0, TRANSACTION_ID_LENGTH);
return(stunHeader);
}
return(null);
}
public static STUNHeader ParseSTUNHeader(byte[] buffer)
{
if (buffer != null && buffer.Length > 0 && buffer.Length >= STUN_HEADER_LENGTH)
{
STUNHeader stunHeader = new STUNHeader();
UInt16 stunTypeValue = BitConverter.ToUInt16(buffer, 0);
UInt16 stunMessageLength = BitConverter.ToUInt16(buffer, 2);
if (BitConverter.IsLittleEndian)
{
stunTypeValue = Utility.ReverseEndian(stunTypeValue);
stunMessageLength = Utility.ReverseEndian(stunMessageLength);
}
stunHeader.MessageType = STUNMessageTypes.GetSTUNMessageTypeForId(stunTypeValue);
stunHeader.MessageLength = stunMessageLength;
//stunHeader.TransactionId = BitConverter.ToString(buffer, 4, TRANSACTION_ID_LENGTH);
Buffer.BlockCopy(buffer, 4, stunHeader.TransactionId, 0, TRANSACTION_ID_LENGTH);
return(stunHeader);
}
return(null);
}
public static STUNMessage ParseSTUNMessage(byte[] buffer, int bufferLength)
{
if (buffer != null && buffer.Length > 0 && buffer.Length >= bufferLength)
{
STUNMessage stunMessage = new STUNMessage();
stunMessage.Header = STUNHeader.ParseSTUNHeader(buffer);
if (stunMessage.Header.MessageLength > 0)
{
stunMessage.Attributes = STUNAttribute.ParseMessageAttributes(buffer, STUNHeader.STUN_HEADER_LENGTH, bufferLength);
}
return(stunMessage);
}
return(null);
}
public static STUNMessage ParseSTUNMessage(byte[] buffer, int bufferLength)
{
if (buffer != null && buffer.Length > 0 && buffer.Length >= bufferLength)
{
STUNMessage stunMessage = new STUNMessage();
stunMessage._receivedBuffer = buffer.Take(bufferLength).ToArray();
stunMessage.Header = STUNHeader.ParseSTUNHeader(buffer);
if (stunMessage.Header.MessageLength > 0)
{
stunMessage.Attributes =
STUNAttribute.ParseMessageAttributes(buffer, STUNHeader.STUN_HEADER_LENGTH, bufferLength);
}
if (stunMessage.Attributes.Count > 0 &&
stunMessage.Attributes.Last().AttributeType == STUNAttributeTypesEnum.FingerPrint)
{
// Check fingerprint.
var fingerprintAttribute = stunMessage.Attributes.Last();
var input = buffer.Take(buffer.Length - STUNAttribute.STUNATTRIBUTE_HEADER_LENGTH -
FINGERPRINT_ATTRIBUTE_CRC32_LENGTH).ToArray();
uint crc = Crc32.Compute(input) ^ FINGERPRINT_XOR;
byte[] fingerPrint = (BitConverter.IsLittleEndian)
? BitConverter.GetBytes(NetConvert.DoReverseEndian(crc))
: BitConverter.GetBytes(crc);
//logger.LogDebug($"STUNMessage supplied fingerprint attribute: {fingerprintAttribute.Value.HexStr()}.");
//logger.LogDebug($"STUNMessage calculated fingerprint attribute: {fingerPrint.HexStr()}.");
if (fingerprintAttribute.Value.HexStr() == fingerPrint.HexStr())
{
stunMessage.isFingerprintValid = true;
}
}
return(stunMessage);
}
return(null);
}
public static STUNHeader ParseSTUNHeader(byte[] buffer)
{
if (buffer != null && buffer.Length > 0 && buffer.Length >= STUN_HEADER_LENGTH)
{
STUNHeader stunHeader = new STUNHeader();
UInt16 stunTypeValue = BitConverter.ToUInt16(buffer, 0);
UInt16 stunMessageLength = BitConverter.ToUInt16(buffer, 2);
if (BitConverter.IsLittleEndian)
{
stunTypeValue = Utility.ReverseEndian(stunTypeValue);
stunMessageLength = Utility.ReverseEndian(stunMessageLength);
}
stunHeader.MessageType = STUNMessageTypes.GetSTUNMessageTypeForId(stunTypeValue);
stunHeader.MessageLength = stunMessageLength;
//stunHeader.TransactionId = BitConverter.ToString(buffer, 4, TRANSACTION_ID_LENGTH);
Buffer.BlockCopy(buffer, 4, stunHeader.TransactionId, 0, TRANSACTION_ID_LENGTH);
return stunHeader;
}
return null;
}
public STUNMessage(STUNMessageTypesEnum stunMessageType)
{
Header = new STUNHeader(stunMessageType);
}
public STUNMessage(STUNMessageTypesEnum stunMessageType)
{
Header = new STUNHeader(stunMessageType);
}
