Re: [Sqlgrey-users] greylisting and UTF8

[Lionel B. <lio...@bo...>]

Karl O. Pinc wrote:
> On 11/25/2007 05:10:23 AM, Lionel Bouton wrote:
>   
>> Nicolas STRANSKY wrote the following on 25.11.2007 11:53 :
>>
>> This isn't the problem. Mail addresses use ASCII. In ASCII some
>> characters aren't valid UTF-8 sequences. So you should't use UTF-8 to
>> store email adresses...
>>     
>
> There are (now) unicode domain name representations.
>   

They are quite old. The mechanism used by IDN predates the first SQLgrey
release :-)

> Does sqlgrey deal with internationalized domain names (RFC3490)
> punycode (RFC3492) and friends (RFC3454, RFC3491) or is that already
> taken care of by the MTAs?
>   

SQLgrey doesn't care *one bit*. IDN uses an Unicode encoding which is
meant to work with tools understanding ASCII only (which SQLgrey is).
IDN wouldn't be possible if you'd have to change each and every name
server, mail server, tool used for mail handling out there...

The only greylisting problem with SQLgrey could be the heuristics used
to guess if a name is more likely to be a mail server or a personal
(dialup/ADSL/cable/...) connection. Even then, the heuristics only care
about the first part of the DNS name, not the DNS zone it is attached
to. So they should be OK even with IDN.
> What does domain name internationalization mean for the content
> of sqlgrey's db?
>   

Nothing much, if you have tools designed to show the DB content, you'll
have to make them IDN-aware (which means they'll output unicode by the
way) in order to decode the domain name.

The only real practical problem with SQLgrey and IDN is the log. You'll
have the ASCII-encoded names in them and that could make things
difficult to diagnose. Though I suspect that everybody logs
ASCII-encoded names, so matching SQLgrey log entries with Postfix' or
other mail-related tool's ones should be OK.

Lionel