Re: [Exim] Re: Underscore in domain is being rejected

Top Page
Delete this message
Reply to this message
Author: Sean Rima
Date:  
To: exim-users
Subject: Re: [Exim] Re: Underscore in domain is being rejected
On Sat, 29 Jun 2002, Derrick Hudson moaned:

>| ,----
>| | 501 <mail@st_agency.com>: malformed address: _agency.com> may not
>| | follow <mail@st
>| `----
>
> That's right. "_agency.com" may not follow "mail@st".
>
> See RFC 2821, section 4.1.2. :
>
>    [...]  characters outside the set of alphas, digits, and hyphen
>    MUST NOT appear in domain name labels for SMTP clients or servers.
>    In particular, the underscore character is not permitted.  SMTP
>    servers that receive a command in which invalid character codes
>    have been employed, and for which there are no other reasons for
>    rejection, MUST reject that command with a 501 response.



I thought I remembered something about RFC but it eluded me :)

>| In my fetchmail log,
>
> You're not using the option
>     mda "/usr/sbin/exim %T"
> in your .fetchmailrc?  That's not good since fetchmail does not have a
> complete SMTP implementation.  (ie it won't bounce messages like the
> above that are rejected by exim)

>


I don't use mda in my fetchmail, so you think it maybe better to use it
instead of using the smtp in fetchmail.

>| Any suggestions
>
> Don't do syntax checks if you want to allow invalid syntax :-). If
> you are using exim 4 (I'm not sure about exim 3) you can sidestep the
> problem using the 'mda' option in fetchmail -- local injection of mail
> is not subject to the ACLs.
>


I prefer to use as much security as possible :)

Sean

- --
  Sean Rima                                http://www.tcob1.net
  Linux User:      231986          Jabber:   tcobone@???
  THE VIEWS EXPRESSED HERE ARE NOT NECESSARILY THOSE OF MY WIFE.