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SPF lookup with intermediate ISP mail relay

2004-11-23 23:24:03
Hello

I have recently setup SPF checks here. Not yet doing the DNS TXT records, only checking the mail as it arrives.

The problem is that all the mail is not delivered to the local mail server from the originating mail server, it goes via an ISP. So that ISP's server is effectively relaying it to here.

The SPF implementation here is doing its job perfectly. When for eg, mail arrives from hotmail.com (who advertise SPF records), it find the records and decides the SPF test failed by quite reasonably saying that the address of our ISP's relying mail server (from which the mail arrived) is not the same as that advertised by hotmail.com

In the msg headers there is a Received: for every hop, including the hotmail server.

Does anyone know what if anything I can adjust to make SPF match the right header info, or how I might adjust the headers (using sendmail) as they arrive so that the right info can be seen?

The only clue I have found so far is "sendmail will not expose the MAIL FROM: sender address by default. So
if you're using sendmail, please add this to /etc/sendmail.cf :
H?l?X-Envelope-From: $f

Does that make any sense?

I did this (to /etc/mail/sendmail.cf) but its made no difference and indeed no header titled 'X-Envelope-From:' is added to incoming mail that sendmail is processing. If that is indeed the solution, is there some trick to getting sendmail.cf to have that added to the messages?

many thanks

rolf.