public static List <STUNAttribute> ParseMessageAttributes(byte[] buffer, int startIndex, int endIndex)
{
if (buffer != null && buffer.Length > startIndex && buffer.Length >= endIndex)
{
List <STUNAttribute> attributes = new List <STUNAttribute>();
int startAttIndex = startIndex;
while (startAttIndex < endIndex)
{
UInt16 stunAttributeType = BitConverter.ToUInt16(buffer, startAttIndex);
UInt16 stunAttributeLength = BitConverter.ToUInt16(buffer, startAttIndex + 2);
byte[] stunAttributeValue = null;
if (BitConverter.IsLittleEndian)
{
stunAttributeType = Utility.ReverseEndian(stunAttributeType);
stunAttributeLength = Utility.ReverseEndian(stunAttributeLength);
}
if (stunAttributeLength > 0)
{
if (stunAttributeType == (int)STUNAttributeTypesEnum.Username && stunAttributeLength > buffer.Length - startIndex - 4)
{
// Received some STUN messages where the username is shorter than the claimed length.
int realLength = buffer.Length - startIndex - 4;
stunAttributeValue = new byte[realLength];
Buffer.BlockCopy(buffer, startIndex + 4, stunAttributeValue, 0, realLength);
}
else
{
stunAttributeValue = new byte[stunAttributeLength];
Buffer.BlockCopy(buffer, startIndex + 4, stunAttributeValue, 0, stunAttributeLength);
}
}
STUNAttributeTypesEnum attributeType = STUNAttributeTypes.GetSTUNAttributeTypeForId(stunAttributeType);
STUNAttribute attribute = null;
if (attributeType == STUNAttributeTypesEnum.ChangeRequest)
{
attribute = new STUNChangeRequestAttribute(stunAttributeValue);
}
else if (attributeType == STUNAttributeTypesEnum.MappedAddress)
{
attribute = new STUNAddressAttribute(stunAttributeValue);
}
else
{
attribute = new STUNAttribute(attributeType, stunAttributeLength, stunAttributeValue);
}
attributes.Add(attribute);
startAttIndex = startAttIndex + 4 + stunAttributeLength;
}
return(attributes);
}
else
{
return(null);
}
}
public void STUNPrimaryReceived(IPEndPoint localEndPoint, IPEndPoint receivedEndPoint, byte[] buffer, int bufferLength)
{
try
{
//Console.WriteLine("\n=> received from " + IPSocketAddress.GetSocketString(receivedEndPoint) + " on " + IPSocketAddress.GetSocketString(receivedOnEndPoint));
//Console.WriteLine(Utility.PrintBuffer(buffer));
STUNMessage stunRequest = STUNMessage.ParseSTUNMessage(buffer, bufferLength);
//Console.WriteLine(stunRequest.ToString());
FireSTUNPrimaryRequestInTraceEvent(localEndPoint, receivedEndPoint, stunRequest);
STUNMessage stunResponse = GetResponse(receivedEndPoint, stunRequest, true);
byte[] stunResponseBuffer = stunResponse.ToByteBuffer();
bool changeAddress = false;
bool changePort = false;
foreach (STUNAttribute attr in stunRequest.Attributes)
{
if (attr.AttributeType == STUNAttributeTypesEnum.ChangeRequest)
{
STUNChangeRequestAttribute changeReqAttr = (STUNChangeRequestAttribute)attr;
changeAddress = changeReqAttr.ChangeAddress;
changePort = changeReqAttr.ChangePort;
break;
}
}
if (!changeAddress)
{
if (!changePort)
{
//Console.WriteLine("<= sending to " + IPSocketAddress.GetSocketString(receivedEndPoint) + " from " + IPSocketAddress.GetSocketString(m_primaryEndPoint));
m_primarySend(receivedEndPoint, stunResponseBuffer);
FireSTUNPrimaryResponseOutTraceEvent(m_primaryEndPoint, receivedEndPoint, stunResponse);
}
else
{
//Console.WriteLine("<= sending to " + IPSocketAddress.GetSocketString(receivedEndPoint) + " from " + IPSocketAddress.GetSocketString(m_primaryDiffPortEndPoint));
m_primaryDiffPortSocket.Send(stunResponseBuffer, stunResponseBuffer.Length, receivedEndPoint);
FireSTUNPrimaryResponseOutTraceEvent(m_primaryDiffPortEndPoint, receivedEndPoint, stunResponse);
}
}
else
{
if (!changePort)
{
//Console.WriteLine("<= sending to " + IPSocketAddress.GetSocketString(receivedEndPoint) + " from " + IPSocketAddress.GetSocketString(m_secondaryEndPoint));
m_secondarySend(receivedEndPoint, stunResponseBuffer);
FireSTUNSecondaryResponseOutTraceEvent(m_secondaryEndPoint, receivedEndPoint, stunResponse);
}
else
{
//Console.WriteLine("<= sending to " + IPSocketAddress.GetSocketString(receivedEndPoint) + " from " + IPSocketAddress.GetSocketString(m_secondaryDiffPortEndPoint));
m_secondaryDiffPortSocket.Send(stunResponseBuffer, stunResponseBuffer.Length, receivedEndPoint);
FireSTUNSecondaryResponseOutTraceEvent(m_secondaryDiffPortEndPoint, receivedEndPoint, stunResponse);
}
}
}
catch (Exception excp)
{
logger.Debug("Exception STUNPrimaryReceived. " + excp.Message);
}
}