Alias rule help

[Julian Field]

I would do this at the MTA level, like other posters have advised.
We have *-all lists, which withing them have *-all-people lists, and we 
don't want people outside being able to mail them.

In sendmail.cf we implement this using the following:

KIsEcsList1 regex -a at MATCH ^(cs|el|ce|ie)?ug[0-9]?$
KIsEcsList2 regex -a at MATCH ^.*-all(-[0-9])?$
KIsEcsList3 regex -a at MATCH ^.*-(people|extras)(-[0-9])?$

These define the 3 regexps that match all the mailing lists (examples 
from each line are
IsEcsList1 csug2
IsEcsList2 staff-all, staff-all-1
IsEcsList3 staff-all-people, staff-all-people-2
as that is how the lists are all constructed. Obviously you will need to 
change these to match your own setup.

And then further down in sendmail.cf, this. If you know a reasonable 
amount about sendmail.cf files, then it should be obvious where the 
<tab> characters go to separate the 3 "fields" of each line of a 
sendmail rule.

SLocal_check_rcpt
R$*                     $: $>3 $1               Focus on host
R$*                     $: $>"QualifyDomain" $1 Make fully-qualified
R$* <@ $* $m. > $*      $1 <@ *LOCAL* >         Is recipient an ECS address?
R$* <@ *LOCAL* > $*     $: $(IsEcsList1 $1 $) <@ *LOCAL* > $2   ECS list?
R$* <@ *LOCAL* > $*     $: $(IsEcsList2 $1 $) <@ *LOCAL* > $2   ECS list?
R$* <@ *LOCAL* > $*     $: $(IsEcsList3 $1 $) <@ *LOCAL* > $2   ECS list?
R at MATCH <@ *LOCAL* > $*    $#error $@ 5.1.2 $: Please contact ECS Help Desk

# If address is unqualified, add *LOCAL* as the destination hostname.
SQualifyDomain
R$* < @ $* > $*         $@ $1 < @ $2 > $3       Already fully qualified
R$+                     $@ $1 < @ *LOCAL* >     Add local qualification

That should tell you all you need to implement restrictions at MTA level 
in sendmail to disable addresses that match regular expressions.

On 15/12/08 16:13, Nasser Al-Zawawi wrote:
>
> Hi,
>
> I have a RedHat ES 4 server running sendmail (8.13.1) and I am using 
> the latest MailScanner version (4.73.4-2), ClamAV 0.94.2 and 
> SpamAssassin 3.2.5. I need help with a rule that should block all 
> outside users from sending emails to our aliases and only allow them 
> to come from people from our domain. For example we have an alias 
> called _/all_users/_ and it is literally all users on the system. 
> Somehow spammers are able to see these aliases on the system (I hope 
> there is a way to disallow them from seeing the aliases) and then they 
> are sending SPAMs to these aliases so when they send a spam to 
> _/all_users/_ at domain.com <mailto:_all_users_ at domain.com> everybody 
> gets that spam. Could somebody write this rule and show what directive 
> to put in the MailScanner.conf if any. I have tried a few but none worked.
>
> Best regards,
>
>
> Nasser
>

Jules

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