Mark Shewmaker wrote:
On Thu, 2004-10-14 at 21:54, Mark wrote:
This is the text:
If the domain does not exist (RCODE 3), check_host() exits
immediately with the result "Fail" and a reason of
"Domain Does Not Exist"
[...]
It is perfectly legit to use a domain name for which only an MX
record exists, for instance. An immediate result "Fail" because of
"Domain Does Not Exist" appears in error.
But a domain name for which only an MX record exists will not get an
RCODE 3 response in the first place, since there do exist some records
for that domain.
That is true. I overlooked that point.
Since the whole point of SPF is to verify the bounce-ability of Return
Paths, and since by definition a Return Path pointing to a domain that
does not exist in any way cannot *ever* accept a bounce, I don't see
the objection to check_host() returning a "Fail" in that case.
The issue remains, of course, that you cannot return a "fail" result for a
non-existent SPF record. A domain which does not exist, is not the same as a
forgery.
Come to think of it, sendmail actually cuts such "RCODE 3" domains short,
before you can do anything else even:
MAIL FROM: <bla(_at_)reallynonexistent(_dot_)org>
501 5.1.8 Domain of sender address bla(_at_)reallynonexistent(_dot_)org does
not exist
So maybe the whole issue is moot to begin with.
- Mark
System Administrator Asarian-host.org
---
"If you were supposed to understand it,
we wouldn't call it code." - FedEx