mod_sasl2_fast: Fix harmless off-by-one error (invalidates existing tokens!) Problem: This was causing the key to become "<token>--cur" instead of the expected "<token>-cur". As the same key was used by the code to both set and get, it still worked. Rationale for change: Although it worked, it's unintended, inconsistent and messy. It increases the chances of future bugs due to the unexpected format. Side-effects of change: Existing '--cur' entries will not be checked after this change, and therefore existing FAST clients will fail to authenticate until they attempt password auth and obtain a new FAST token. Existing '--cur' entries in storage will not be cleaned up by this commit, but this is considered a minor issue, and okay for the relatively few FAST deployments.

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labels:
- 'Type-S2SAuth'
---

Introduction
============

[PKIX over Secure HTTP (POSH)][rfc7711] describes a method of
securely delegating a domain to a hosting provider, without that hosting
provider needing keys and certificates covering the hosted domain.

# Validating

This module performs POSH validation of other servers. It is *not*
needed to delegate your own domain.

# Delegation

You can generate the JSON delegation file from a certificate by running
`prosodyctl mod_s2s_auth_posh /path/to/example.crt`. This file needs to
be served at `https://example.com/.well-known/posh/xmpp-server.json`.