On Sep 8, 2004, at 9:37 AM, Andrew Newton wrote:
It is also the opinion of the co-chairs that many in the working group
are willing to deploy MAIL FROM checking as specified in
draft-mengwong-spf. Therefore, we ask for consideration of the
following proposal:
The ABNF in -protocol 3.4.1 is (mostly from a post by Wayne)
version = "spf2." ver-minor "/" ver-scope *( "," ver-scope )
ver-minor = 1*DIGIT
ver-scope = "pra" / "mailfrom" / name
name = alpha *( alpha / digit / "-" / "_" / "." )
I agree with decoupling scope from the base record format. If we're
going to modify -protocol, I suggest we further decouple the version
string from the base record format. To wit:
version = "spf/" ver-major "." ver-minor "/" ver-scope *( ","
ver-scope )
ver-major = 1*DIGIT
ver-minor = 1*DIGIT
ver-scope = "pra" / "mailfrom" / name
name = alpha *( alpha / digit / "-" / "_" / "." )
Doing this would help further delineate the static and variable parts
of the version string. I also recommend that the RR type defined for
-protocol be modified to drop the superfluous "2".
Sample applied use:
example.com. IN SPF "spf/2.0/pra,mailfrom mx a:smtp.example.com
a:smtp.marketingco.com ?all"
IN SPF "spf/2.0/mta mx a:smtp.example.com -a:192.0.2.0/24
?all"
IN TXT "spf/2.0/pra,mailfrom mx a:smtp.example.com
a:smtp.marketingco.com ?all"
IN TXT "spf/2.0/mta mx a:smtp.example.com -a:192.0.2.0/24
?all"
In future versions, perhaps:
example.com IN SPF "spf/2.1/xmlstr <spf
xmlns='http://domain.com/1'><pra><m><mx/></m></pra></spf>"
example.com IN SPF "spf/2.2/xmldoc http://example.com/spf/policy.xml";
The question before the working group: assuming no technical errors
with the above, is there anybody who vehemently objects with this
proposal?
I see no harm in taking this opportunity to allow for future versions
of Sender-ID with additional scopes and different record formats.
Tripp