public static IPEndPoint GetChangedAddressAttribute(StunMessage5389 response)
{
var changedAddressAttribute = response?.Attributes.FirstOrDefault(t => t.Type == AttributeType.ChangedAddress);
if (changedAddressAttribute == null)
{
return(null);
}
var address = (ChangedAddressAttribute)changedAddressAttribute.Value;
return(new IPEndPoint(address.Address, address.Port));
}
public static IPEndPoint GetMappedAddressAttribute(StunMessage5389 response)
{
var mappedAddressAttribute = response?.Attributes.FirstOrDefault(t => t.Type == AttributeType.MappedAddress);
if (mappedAddressAttribute == null)
{
return(null);
}
var mapped = (MappedAddressAttribute)mappedAddressAttribute.Value;
return(new IPEndPoint(mapped.Address, mapped.Port));
}
public static IPEndPoint?GetXorMappedAddressAttribute(this StunMessage5389 response)
{
var mappedAddressAttribute =
response.Attributes.FirstOrDefault(t => t.Type == AttributeType.XorMappedAddress) ??
response.Attributes.FirstOrDefault(t => t.Type == AttributeType.MappedAddress);
if (mappedAddressAttribute is null)
{
return(null);
}
var mapped = (AddressStunAttributeValue)mappedAddressAttribute.Value;
return(new IPEndPoint(mapped.Address !, mapped.Port));
}
public static IPEndPoint?GetOtherAddressAttribute(this StunMessage5389 response)
{
var addressAttribute =
response.Attributes.FirstOrDefault(t => t.Type == AttributeType.OtherAddress) ??
response.Attributes.FirstOrDefault(t => t.Type == AttributeType.ChangedAddress);
if (addressAttribute is null)
{
return(null);
}
var address = (AddressStunAttributeValue)addressAttribute.Value;
return(new IPEndPoint(address.Address !, address.Port));
}
private async Task <StunResult5389> BindingTestBaseAsync(IPEndPoint remote, bool notifyChanged, CancellationToken token)
{
BindingTestResult res;
var test = new StunMessage5389 {
StunMessageType = StunMessageType.BindingRequest
};
var(response1, _, local1) = await TestAsync(test, remote, remote, token);
var mappedAddress1 = AttributeExtensions.GetXorMappedAddressAttribute(response1);
var otherAddress = AttributeExtensions.GetOtherAddressAttribute(response1);
var local = local1 == null ? null : new IPEndPoint(local1, LocalEndPoint.Port);
if (response1 == null)
{
res = BindingTestResult.Fail;
}
else if (mappedAddress1 == null)
{
res = BindingTestResult.UnsupportedServer;
}
else
{
res = BindingTestResult.Success;
}
if (notifyChanged)
{
_bindingSubj.OnNext(res);
PubSubj.OnNext(mappedAddress1);
}
LocalSubj.OnNext(LocalEndPoint);
return(new StunResult5389
{
BindingTestResult = res,
LocalEndPoint = local,
PublicEndPoint = mappedAddress1,
OtherEndPoint = otherAddress
});
}
private async Task <StunResult5389> FilteringBehaviorTestBaseAsync(CancellationToken token)
{
// test I
var result1 = await BindingTestBaseAsync(RemoteEndPoint, true, token);
try
{
if (result1.BindingTestResult != BindingTestResult.Success)
{
return(result1);
}
if (result1.OtherEndPoint == null ||
Equals(result1.OtherEndPoint.Address, RemoteEndPoint.Address) ||
result1.OtherEndPoint.Port == RemoteEndPoint.Port)
{
result1.FilteringBehavior = FilteringBehavior.UnsupportedServer;
return(result1);
}
// test II
var test2 = new StunMessage5389
{
StunMessageType = StunMessageType.BindingRequest,
Attributes = new[] { AttributeExtensions.BuildChangeRequest(true, true) }
};
var(response2, _, _) = await TestAsync(test2, RemoteEndPoint, result1.OtherEndPoint, token);
if (response2 != null)
{
result1.FilteringBehavior = FilteringBehavior.EndpointIndependent;
return(result1);
}
// test III
var test3 = new StunMessage5389
{
StunMessageType = StunMessageType.BindingRequest,
Attributes = new[] { AttributeExtensions.BuildChangeRequest(false, true) }
};
var(response3, remote3, _) = await TestAsync(test3, RemoteEndPoint, RemoteEndPoint, token);
if (response3 == null)
{
result1.FilteringBehavior = FilteringBehavior.AddressAndPortDependent;
return(result1);
}
if (Equals(remote3.Address, RemoteEndPoint.Address) && remote3.Port != RemoteEndPoint.Port)
{
result1.FilteringBehavior = FilteringBehavior.AddressAndPortDependent;
}
else
{
result1.FilteringBehavior = FilteringBehavior.UnsupportedServer;
}
return(result1);
}
finally
{
_filteringBehaviorSubj.OnNext(result1.FilteringBehavior);
}
}
