> From owner-misc+M146963=martin=martinbrandenburg....@openbsd.org Sat Feb 21 > 23:48:17 2015 > Date: Sat, 21 Feb 2015 17:51:28 -0500 > Message-ID: > <CAAmqg_CnTsisEvNEc2TrV8i=y3l3k_vtsa-6ndbrno-8jug...@mail.gmail.com> > Subject: spamd whitelist > From: F Bax <fbax...@gmail.com> > To: OpenBSD <misc@openbsd.org> > List-ID: <misc.openbsd.org> > > In this archived message; Peter explains here how to get ip address for > various gmail servers - which can then be added to whitelist... > > http://marc.info/?l=openbsd-misc&m=136449396910976&w=2 > > When I try this process for yahoo.com; I get > > $ host -ttxt yahoo.com > yahoo.com descriptive text "v=spf1 redirect=_spf.mail.yahoo.com" > $ host -ttxt _spf.mail.yahoo.com > _spf.mail.yahoo.com descriptive text "v=spf1 ptr:yahoo.com ptr:yahoo.net > ?all" > > What should I do with "ptr" info? > >
See http://www.openspf.org/SPF_Record_Syntax Any IP connecting to you that has a reverse DNS entry ending yahoo.com or yahoo.net and whose forward matches the reverse is allowed to send mail from yahoo.com. So short of doing a reverse lookup on every single IP number (please don't), there's no way to extract this information from SPF records. That doesn't mean you can't find the information somewhere else. -- Martin
