TLS Early Data on the server side

[arcusfelis]

Hi, are there any plans on implementing early data on the server side?

There is an example of usage, and there is even an option on how to enable early_data on the server side:
https://www.erlang.org/doc/apps/ssl/using_ssl.html

But I don't see the way of receiving that data on the server side.
Digging into the code, it looks like it is not implemented yet.

There was a placeholder in Erlang 26, but I haven't found it in the newer versions.

[IngelaAndin]

It was implemented here aece091

You should be able to receive the early data the same way as any application data. The server user process should not have to care if the data is early or not. If the server is configured to accept early data and
session tickets are use to so that the client can send early data it should work out of the box.

[arcusfelis]

@IngelaAndin oh, interesting, will try.

[arcusfelis]

@IngelaAndin Is there a way to check if the data came inside 0-RTT?

In XMPP, there should be a different behaviour if it comes inside early data, comparing to the regular encrypted data (i.e. extra checks to deny replay attacks).