---

labels:

- 'Stage-Alpha'

- 'Type-S2SAuth'

summary: S2S authentication using DANE

...

Introduction

============

This module implements DANE as described in [Using DNS Security

Extensions (DNSSEC) and DNS-based Authentication of Named Entities

(DANE) as a Prooftype for XMPP Domain Name

Associations](http://tools.ietf.org/html/draft-miller-xmpp-dnssec-prooftype).

Dependencies

============

This module requires a DNSSEC aware DNS resolver. Prosodys internal DNS

module does not support DNSSEC. Therefore, to use this module, a

replacement is needed, such as [this

one](https://www.zash.se/luaunbound.html).

LuaSec 0.5 or later is also required.

Configuration

=============

After [installing the module][doc:installing\_modules], just add it to

`modules_enabled`;

    modules_enabled = {

     ...

     "s2s_auth_dane";

    }

DANE Uses

---------

By default, only DANE uses are enabled.

    dane_uses = { "DANE-EE", "DANE-TA" }

  Use flag    Description

  ----------- -------------------------------------------------------------------------------------------------------

  `DANE-EE`   Most simple use, usually a fingerprint of the full certificate or public key used the service

  `DANE-TA`   Fingerprint of a certificate or public key that has been used to issue the service certificate

  `PKIX-EE`   Like `DANE-EE` but the certificate must also pass normal PKIX trust checks (ie standard certificates)

  `PKIX-TA`   Like `DANE-TA` but must also pass normal PKIX trust checks (ie standard certificates)

DNS Setup

=========

In order for other services to verify your site using using this plugin,

you need to publish TLSA records (and they need to have this plugin).

Here's an example using `DANE-EE Cert SHA2-256` for a host named

`xmpp.example.com` serving the domain `example.com`.

    $ORIGIN example.com.

    ; Your standard SRV record

    _xmpp-server._tcp.example.com IN SRV 0 0 5269 xmpp.example.com.

    ; IPv4 and IPv6 addresses

    xmpp.example.com. IN A 192.0.2.68

    xmpp.example.com. IN AAAA 2001:0db8:0000:0000:4441:4e45:544c:5341

    ; The DANE TLSA records.

    _5269._tcp.xmpp.example.com. 300 IN TLSA 3 0 1 E3B0C44298FC1C149AFBF4C8996FB92427AE41E4649B934CA495991B7852B855

    ; If your zone file tooling does not support TLSA records, you can try the raw binary format:

    _5269._tcp.xmpp.example.com. 300 IN TYPE52 \# 35 030001E3B0C44298FC1C149AFBF4C8996FB92427AE41E4649B934CA495991B7852B855

[List of DNSSEC and DANE

tools](http://www.internetsociety.org/deploy360/dnssec/tools/)

Further reading

===============

-   [DANE Operational Guidance][rfc7671]

Compatibility

=============

Works with Prosody 0.9 until 0.11.

**Broken** since [trunk revision 756b8821007a](https://hg.prosody.im/trunk/rev/756b8821007a).

Known issues

============

-   A race condition between the DANE lookup and completion of the TLS

    handshake may cause a crash. This does not happen in **trunk**

    thanks to better async support.