[jdev] saslprep and nodeprep

[Waqas Hussain]

On Tue, Sep 25, 2012 at 11:50 PM, Peter Saint-Andre <stpeter at stpeter.im> wrote:
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> Just FYI, I compared SASLprep (RFC 4013) and Nodeprep (RFC 3920)
> recently and it seems that any XMPP localpart that conforms to
> Nodeprep also conforms to SASLprep

Correct. A localpart conforming to nodeprep also conforms to saslprep.

> , so there is no need to perform
> separate SASLprep processing in XMPP client and server code. If you
> disagree with my conclusions, please let me know. :)
>
> Peter

Not true. SASLprep maps non-ASCII space characters [StringPrep, C.1.2]
to SPACE (U+0020). Nodeprep forbids C.1.2 characters. A string with
non-ASCII space characters needs to be saslprepped before it can pass
nodeprep. Of course, we can get away with just replacing spaces rather
than full saslprep.

Also, all this only applies if the SASL authentication string is an
XMPP localpart :)

Aside: I've been analyzing our various old stringprep profiles (their
overlap, etc), and will soon be comparing them the new stringprep.

--
Waqas Hussain