mod_scram_upgrade - add example to config

[licaon-kter]

reading https://docs.ejabberd.im/admin/configuration/modules/#mod_scram_upgrade

and then reading https://docs.ejabberd.im/admin/configuration/toplevel/#auth_scram_hash I see

You shouldn’t change this if you already have passwords generated with a different algorithm - users that have such passwords will not be able to authenticate.

gets me confused

if auth_scram_hash is The default value is sha then how can I upgrade?

[badlop]

The only thing I can say for sure is what I tried:

auth_scram_hash

You shouldn’t change this if you already have passwords generated with a different algorithm - users that have such passwords will not be able to authenticate.

If you setup auth_scram_hash: sha, start ejabberd and register some accounts, their passwords are stored in sha format.

If you then change to auth_scram_hash: sha256, restart ejabberd:

• new accounts with have the password stored as sha256 and can login correctly
• old accounts have the password still stored as sha. When ejabberd offers SCRAM-SHA-256 and the client provides a username+password in sha256, it cannot be authenticated.

---

I wonder how exactly mod_scram_upgrade is designed to be used in practice by an administrator, its use-case.

For example, let's imagine it's SHA-1 right now and SHA-256 is desired. With the configuration is like this:

auth_password_format: scram
auth_scram_hash: sha

Then what should the admin setup?

A) Store new as sha, offer upgrade to sha256?

auth_password_format: scram
auth_scram_hash: sha

modules:
  mod_scram_upgrade:
    offered_upgrades:
      - sha256

B) Store the new as sha256, offer upgrade to sha256?

auth_password_format: scram
auth_scram_hash: sha256

modules:
  mod_scram_upgrade:
    offered_upgrades:
      - sha256

@prefiks any idea here?

---

I also wonder what clients already support XEP-0480 to test the feature

[Neustradamus]

Currently, I know Monal IM which supports it:

• https://github.com/monal-im/Monal/commit/3f0f89b1e7b73963ff32d191ba62d7cfefb60f1d (added by @tmolitor-stud-tu)

It has been requested for XMPP Clients:

• https://github.com/miranda-ng/miranda-ng/issues/4074
• https://github.com/psi-im/psi/issues/725

It has been requested for XMPP Library:

• https://github.com/qxmpp-project/qxmpp/issues/668
• https://github.com/xmppo/go-xmpp/issues/192

It has been requested for XMPP Server:

• https://github.com/maranda/metronome/issues/554

XEP-0480 is linked to this @tmolitor-stud-tu initial request:

• https://github.com/processone/xmpp/issues/80

[tmolitor-stud-tu]

@badlop I guess it is option B) Store the new as sha256, offer upgrade to sha256?