Hey, everyone. A situation has come up on the SPF-Help list where a receiver
is rejecting inbound mail from a domain and it turns out that the problem is
case sensitivity. A test using libspf2 verified that libspf2, at least, is
case sensitive.
Is this an implementation issue or a spec issue, or not an issue at all? What
I mean is:
- Are all DNS-related issues supposed to be case-insensitive, so this does not
need to be in the spec, but certain implementations have implemented it wrong?
- Are all DNS-related issues not specified, so the SPF spec needs to say?
- Or do people need to be aware that case may cause their mail to be rejected?
Evidence presented below....
Regards,
Marc Alaia
srs# spfquery -debug -ip 216.39.67.112 -sender cwjobs-
e2-27265112(_at_)ProcessRequest(_dot_)com -helo DAL1BS110.PROCESSREQUEST.COM
spf_dns_null.c:64 Debug: DNS pre-cache lookup: ProcessRequest.com TXT (16)
spf_dns_resolv.c:144 Debug: DNS resolv looking for: ProcessRequest.com TXT
(16)
spf_dns_null.c:94 Debug: DNS pre-cache found: ProcessRequest.com TXT
(16) TTL: 1800 RR found: 1 herrno: 0 source: resolv
spf_get_spf.c:116 Debug: found SPF record: v=spf1 ptr -all
spf_dns_null.c:64 Debug: DNS pre-cache lookup: 112.67.39.216.in-addr.arpa
PTR (12)
spf_dns_resolv.c:144 Debug: DNS resolv looking for: 112.67.39.216.in-addr.
arpa PTR (12)
spf_dns_null.c:94 Debug: DNS pre-cache found: 112.67.39.216.in-addr.arpa
PTR (12) TTL: 1800 RR found: 1 herrno: 0 source: resolv
spf_eval_id.c:551 Debug: found 1 PTR records for 216.39.67.112 (herrno: 0)
spf_dns_null.c:64 Debug: DNS pre-cache lookup: dal1bs110.processrequest.
com A (1)
spf_dns_resolv.c:144 Debug: DNS resolv looking for: dal1bs110.processrequest.
com A (1)
spf_dns_null.c:94 Debug: DNS pre-cache found: dal1bs110.processrequest.
com A (1) TTL: 30 RR found: 1 herrno: 0 source: resolv
spf_eval_id.c:569 Debug: 0: found 1 A records for dal1bs110.
processrequest.com (herrno: 0)
spf_eval_id.c:586 Debug: 0: 0: found 216.39.67.112
spf_eval_id.c:597 Debug: ProcessRequest.com == dal1bs110.processrequest.com
spf_eval_id.c:605 Debug: sRequest.com == srequest.com SPF header:
version: 1 mech 2/4 mod 0/0 len=8
SPF record: v=spf1 ptr -all
err = No errors (0)
err_msg =
fail
Please see
http://spf.pobox.com/why.html?sender=cwjobs-e2-27265112%40ProcessRequest.com&ip=216.39.67.112&receiver=spfquery
spfquery: domain of ProcessRequest.com does not designate 216.39.67.112 as
permitted sender
Received-SPF: fail (spfquery: domain of ProcessRequest.com does not designate
216.39.67.112 as permitted sender) client-ip=216.39.67.112; envelope-
from=cwjobs-e2-27265112(_at_)ProcessRequest(_dot_)com;
helo=DAL1BS110.PROCESSREQUEST.COM;
Maybe it's the case (ProcessRequest.com vs processrequest.com) that's giving
problems here?? If that's not it, i see no reason why it should fail.
Ah yes, it definatelly is case related:
srs# spfquery -ip 216.39.67.112 -sender
cwjobs-e2-27265112(_at_)processrequest(_dot_)com
-helo DAL1BS110.processrequest.com pass
spfquery: domain of processrequest.com designates 216.39.67.112 as permitted
sender
Received-SPF: pass (spfquery: domain of processrequest.com designates
216.39.67.112 as permitted sender) client-ip=216.39.67.112; envelope-
from=cwjobs-e2-27265112(_at_)processrequest(_dot_)com;
helo=DAL1BS110.processrequest.com;