On 09/Feb/11 05:13, Mark Constable wrote:
On 09/02/11, Sam Varshavchik wrote:
The only thing I can think of would be a transient DNS lookup
failure for pobox.com. mailfromok is accepted only if the SPF
lookup on the MAIL FROM resulted in pass.
That may be possible because I'm in AU and a lookup I just did
now from the same mailserver was...
~ dig txt pobox.com
;; Query time: 245 msec
A transient DNS lookup failure results in an SPF softfail
result, rather.
Isn't it TempError? RFC 4408 says (sect. 4.4)
If all DNS lookups that are made return a server failure (RCODE 2),
or other error (RCODE other than 0 or 3), or time out, then
check_host() exits immediately with the result TempError.
and (sect. 5)
Several mechanisms rely on information fetched from DNS. For these
DNS queries, except where noted, if the DNS server returns an error
(RCODE other than 0 or 3) or the query times out, the mechanism
throws the exception TempError. If the server returns domain does
not exist (RCODE 3), then evaluation of the mechanism continues as
if the server returned no error (RCODE 0) and zero answer records.
and in such cases (sect 2.5.6)
A TempError result means that the SPF client encountered a
transient error while performing the check. Checking software can
choose to accept or temporarily reject the message. If the message
is rejected during the SMTP transaction for this reason, the software
SHOULD use an SMTP reply code of 451 and, if supported, the 4.4.3 DSN
code.
I think this is probably wrong; mailfromok should be accepted if
the SPF lookup resulted in softfail, as well...
So courier is at fault in this particular corner case?
Well, testing BOFHSPFFROM is obviously non-standard.
For the TempError issue above, without looking at the code, I recall
Courier passes the timeout tests (scenario 2) --according to the
results I posted a couple of years ago:
http://www.mail-archive.com/courier-users@lists.sourceforge.net/msg33232.html
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