[atlas] False positives on SSL check?

Hi Ruben,

On 2018/01/31 13:46 , Ruben Herold wrote:
> I tried to monitor on of our services running on https://login.afterbuy.de. 
> I configured an SSL check like (Meassure ID #11090260). All probes response with:
> 
>  Error: timeout reading hello
> 
> But the service is online and reachable. SSLabs SSL check confirmed this.
> So can someone explain what the error message will tell me?

The SSL check is written from scratch and does not contain all of the
extensions and features you find in common SSL libraries. We do update
the code as we find issues.

In this case, login.afterbuy.de just terminates the connection without
sending any kind of error message.

After looking at the difference between what the atlas measurement code
sends and what wget and curl do, my guess is that it is the lack of the
'signature_algorithms' extension that causes the server to drop the
connection.

I will investigate if that is indeed the case. If so, I'll add the
necessary code. Though it may take a couple of months before that will
be available on the probes.

Philip