view mod_s2s_auth_dane/README.markdown @ 4249:64aa1d9d70ac

mod_rest: Catch and log errors in callback promise chain From the code it looks like it should be possible to reply to an error stanza, but it did not. Turns out I was saved by my local developer mode module which throws errors if an attempt is made to create an errror reply to an error stanza. However nothing collects this error from the promise, so all I got was confusion.
author Kim Alvefur <zash@zash.se>
date Sun, 15 Nov 2020 16:25:49 +0100
parents eb56e743abe8
children 83afe4078e6e
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---
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.