ietf
[Top] [All Lists]

Re: SMTP RFC: "MUST NOT" change or delete Received header

2014-03-30 20:08:42
In article <9EC12CC9-81CD-4C3E-ADD1-283615767B17(_at_)nominum(_dot_)com> you 
write:
On Mar 30, 2014, at 6:44 PM, John C Klensin <john-ietf(_at_)jck(_dot_)com> 
wrote:
Whether one accepts it or not, "been here already" tests are not
about debugging.  They are about loop detection and DoS attacks.

Are there MTAs that make use of the Received: header for loop detection?

Mine has since 1998.  If the SMTP daemon sees 100 Received: headers in
an incoming message, it rejects it.  This is both in qmail's SMTP
daemon and mailfront, a better SMTP daemon often used with qmail.

R's,
John



<Prev in Thread] Current Thread [Next in Thread>