After a certificate_request, if no certificates are available, clients now MUST send an empty certificate list (RFC 5246)

[jorupp]

In trying to use the Adafruit M0 with Azure IoT over MQTT-SSL, but having issues opening the connection. @Eskibear dug a bit deeper than I did and found that in this one case, the server was requesting certs, but the client wasn't providing any (not even an empty list), which seemed suspicious.

Is this a firmware issue or a driver issue?

[sandeepmistry]

Hi @jorupp, @Eskibear,

This sounds like a firmware issue to me. Could you please open a support case with Atmel Support then update this issue with the case number so it can be followed up by us later if needed. Thanks.

http://www.atmel.com/design-support/

[sandeepmistry]

Sorry, accidentally closed this, re-opening ...

[jorupp]

We'll see if I filled out that support form right - got a case number from their Salesforce site - 00051323.

[sandeepmistry]

@jorupp excellent, thanks for letting us know!

[sandeepmistry]

@jorupp any news from Atmel/Microchip on this?

There's a PR build of the IDE that contains the new v19.5.2 WINC1500 firmware: arduino/Arduino#6069 (comment). Any one up for testing it with the master version of the library to see if this has been fixed?

[Eskibear]

@sandeepmistry Thanks, this new firmware works for Azure-MQTT.
I can establish the SSL connection with AzureIoTHub using port 8883 usiing Feather M0 now.

[sandeepmistry]

@Eskibear @jorupp great to hear! Thanks for trying it out!

I'm closing this as resolved.