public bool TryParse(byte[] buffer)
{
try
{
int offset = 0;
MessageType = (MessageType)NetBinaryUtil.ReadShort(buffer, ref offset);
int messageLength = (ushort)NetBinaryUtil.ReadShort(buffer, ref offset);
if (MagicCookie != NetBinaryUtil.ReadUInt(buffer, ref offset))
{
return(false);
}
TransactionId = NetBinaryUtil.ReadBytes(buffer, TransactionIdSize, ref offset);
Attributes.Clear();
while (offset < messageLength + 20)
{
var attr = GetAttribute(buffer, ref offset);
if (attr != null)
{
Attributes.Add(attr);
}
}
return(true);
}
catch
{
return(false);
}
}
protected override void ReadBody(byte[] buf, int offset, int size)
{
offset += 2;
ErrorClass = buf[offset++];
ErrorNumber = buf[offset++];
ReasonPhrase = NetBinaryUtil.ReadString(buf, size - 2, ref offset);
}
public void Read(byte[] buf, ref int offset)
{
Type = (AttributeType)NetBinaryUtil.ReadUShort(buf, ref offset);
var size = NetBinaryUtil.ReadUShort(buf, ref offset);
ReadBody(buf, offset, size);
offset += size + GetPadOffset(size);
}
protected override void WriteBody(byte[] buf, ref int offset)
{
buf[offset++] = 0;
buf[offset++] = 0;
buf[offset++] = ErrorClass;
buf[offset++] = ErrorNumber;
NetBinaryUtil.Write(ReasonPhrase, buf, ref offset);
}
protected override void WriteBody(byte[] buf, ref int offset)
{
buf[offset++] = 0;
buf[offset++] = (byte)(m_EndPoint.AddressFamily == AddressFamily.InterNetwork ? 1 : 2);
var port = (ushort)((ushort)m_EndPoint.Port ^ (ushort)(StunMessage.MagicCookie >> 16));
NetBinaryUtil.Write(port, buf, ref offset);
for (int i = 0; i < m_AddressBytes.Length; i++)
{
s_Buffer[i] = (byte)(m_AddressBytes[i] ^ buf[i + 4]);
}
NetBinaryUtil.Write(s_Buffer, m_AddressBytes.Length, buf, ref offset);
}
protected override void ReadBody(byte[] buf, int offset, int size)
{
offset++;
var family = buf[offset++];
var port = (int)(NetBinaryUtil.ReadUShort(buf, ref offset) ^ (ushort)(StunMessage.MagicCookie >> 16));
byte[] address = NetBinaryUtil.ReadBytes(buf, family == 1 ? 4 : 16, ref offset);
for (int i = 0; i < address.Length; i++)
{
address[i] = (byte)(address[i] ^ buf[i + 4]);
}
EndPoint = new IPEndPoint(new IPAddress(address), port);
}
public void Write(ref byte[] buf, ref int offset)
{
var totalSize = 4 + GetPaddedLength() + offset;
if (buf.Length < totalSize)
{
System.Array.Resize(ref buf, System.Math.Max(buf.Length * 2, totalSize));
}
NetBinaryUtil.Write((ushort)Type, buf, ref offset);
NetBinaryUtil.Write((ushort)GetLength(), buf, ref offset);
WriteBody(buf, ref offset);
offset += GetPadOffset(GetLength());
}
protected override void WriteBody(byte[] buf, ref int offset)
{
int flag = 0;
if (ChangeIP)
{
flag |= 4;
}
if (ChangePort)
{
flag |= 2;
}
s_Buffer[3] = (byte)flag;
NetBinaryUtil.Write(s_Buffer, buf, ref offset);
}
StunAttribute GetAttribute(byte[] buf, ref int offset)
{
int tmp = offset;
var type = (AttributeType)NetBinaryUtil.ReadUShort(buf, ref tmp);
switch (type)
{
case AttributeType.MappedAddress:
case AttributeType.SourceAddress:
case AttributeType.ChangedAddress:
case AttributeType.ReflectedFrom:
case AttributeType.ResponseAddress:
{
var attr = new AddressAttribute(type);
attr.Read(buf, ref offset);
return(attr);
}
case AttributeType.XorMappedAddress:
{
var attr = new XorAddressAttribute(type);
attr.Read(buf, ref offset);
return(attr);
}
case AttributeType.ErrorCode:
{
var attr = new ErrorCodeAttribute(type);
attr.Read(buf, ref offset);
return(attr);
}
case AttributeType.ServerName:
case AttributeType.Username:
case AttributeType.Password:
{
var attr = new ErrorCodeAttribute(type);
attr.Read(buf, ref offset);
return(attr);
}
}
var len = NetBinaryUtil.ReadUShort(buf, ref tmp);
offset += len + StunAttribute.GetPadOffset(len);
return(null);
}
public int Write(ref byte[] buf)
{
int offset = 0;
NetBinaryUtil.Write((ushort)MessageType, buf, ref offset);
int attributesLength = 0;
foreach (var attribute in Attributes)
{
attributesLength += StunAttribute.HeaderSize + attribute.GetPaddedLength();
}
NetBinaryUtil.Write((ushort)attributesLength, buf, ref offset);
NetBinaryUtil.Write(MagicCookie, buf, ref offset);
NetBinaryUtil.Write(TransactionId, TransactionIdSize, buf, ref offset);
foreach (var attribute in Attributes)
{
attribute.Write(ref buf, ref offset);
}
return(offset);
}
protected override void WriteBody(byte[] buf, ref int offset)
{
NetBinaryUtil.Write(Text, buf, ref offset);
}
protected override void ReadBody(byte[] buf, int offset, int size)
{
NetBinaryUtil.ReadString(buf, size, ref offset);
}
