public void Sign(string password)
{
var messageBytes = GetAsBytes(24);
var saslPassword = SaslPrep.Process(password);
MessageIntegrity = new MessageIntegrityAttribute
{
Value = new HMACSHA1(Encoding.UTF8.GetBytes(saslPassword)).ComputeHash(messageBytes)
};
}
public static StunRecord Read(byte[] bytes)
{
var record = new StunRecord();
var idx = 0;
record.MessageType = (StunMessageType)BinaryPrimitives.ReadUInt16BigEndian(bytes.AsSpan(idx));
idx += 2;
var stunMessageLength = BinaryPrimitives.ReadUInt16BigEndian(bytes.AsSpan(idx));
idx += 2;
var stunMessageCookie = BinaryPrimitives.ReadInt32BigEndian(bytes.AsSpan(idx));
idx += 4;
if (stunMessageCookie != StunRecord.MessageCookie)
{
throw new InvalidOperationException("Malformed STUN packet");
}
record.MessageTransactionId = bytes.AsSpan(idx, 12).ToArray();
idx += 12;
record.StunAttributes = new List <StunAttribute>();
while (idx < bytes.Length)
{
var stunAttributeType = (StunAttributeType)BinaryPrimitives.ReadUInt16BigEndian(bytes.AsSpan(idx));
idx += 2;
var stunAttributeLength = BinaryPrimitives.ReadUInt16BigEndian(bytes.AsSpan(idx));
idx += 2;
var stunAttributePaddingRemainder = (byte)(stunAttributeLength % 4);
var stunAttributePadding = (byte)(stunAttributePaddingRemainder == 0 ? 0 : 4 - stunAttributePaddingRemainder);
var stunAttributeValue = bytes.AsSpan(idx, stunAttributeLength).ToArray();
idx += stunAttributeLength;
if (stunAttributePadding > 0)
{
idx += stunAttributePadding;
}
StunAttribute stunAttribute;
switch (stunAttributeType)
{
case StunAttributeType.Username:
stunAttribute = new UsernameAttribute();
break;
case StunAttributeType.IceControlled:
stunAttribute = new IceControlledAttribute();
break;
case StunAttributeType.Priority:
stunAttribute = new PriorityAttribute();
break;
case StunAttributeType.MessageIntegrity:
stunAttribute = new MessageIntegrityAttribute();
break;
case StunAttributeType.Fingerprint:
stunAttribute = new FingerprintAttribute();
break;
default:
stunAttribute = new StunAttribute
{
Type = stunAttributeType
};
break;
}
stunAttribute.Value = stunAttributeValue;
if (stunAttribute.Type != StunAttributeType.MessageIntegrity &&
stunAttribute.Type != StunAttributeType.Fingerprint)
{
record.StunAttributes.Add(stunAttribute);
}
}
return(record);
}
