Re: [exim] Implementation of SPF - flaw?

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Autore: Heiko Schlittermann
Data:  
To: exim-users
Oggetto: Re: [exim] Implementation of SPF - flaw?
Hi,

> > The string "localhost is always allowed." can be found in libspf2.a
> So this is wanted by exim! I did not check what SPF specs say about it, but


libspf2 is the library, Exim links against. So this is probably a
default, Exim relies on.

> this would mean, my local users CAN forge sender addresses?! Does this make
> sense?!


Local users on your MX (Mail In, SPF checking host), yes (if I do not miss anything). Do
you have any local users there?

The RFC does not seem to mention localhost specifically, but libspf2 seems
do do something like:

        /* Give localhost a free ride */
        if (SPF_request_is_loopback(spf_request))
                return SPF_i_done(*spf_responsep, SPF_RESULT_PASS,
                                                SPF_REASON_LOCALHOST, SPF_E_SUCCESS);




    Best regards from Dresden/Germany
    Viele Grüße aus Dresden
    Heiko Schlittermann
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