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Re: People keep misunderstanding what "Pass" and "Neutral" mean

2005-05-17 16:12:56
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Scott Kitterman wrote:
If PASS means authorized, but not necessarily authentic, then I don't
think SPF mail from is a suitable basis for reputation.

If PASS means authorized and should be treated as if it's authentic,
then you can use if for reputation.

I think you're missing what authorization actually means.

  "1.2.3.4 is authorized to use example.com as the HELO/MAIL FROM identity
  when sending mail."

...means nothing other than...

  "If 1.2.3.4 sends mail with example.com as the HELO/MAIL FROM identity,
  you can hold the owner of example.com responsible."

There you have it.  And what does "authentic" mean other than "I know who 
takes responsibility for it"?

Besides, the concept of perfect authentication is entirely virtual because 
my trusted systems can always be hacked or suffer some other bad fate that 
kills their integrity.  Does this mean I don't have to take responsibility 
for what the compromised systems did?  No, it doesn't, at least not as far 
as spam is concerned.  Reputation services won't care about me not being 
personally responsible, they'll just blacklist my systems anyway.  And it 
really couldn't be any other way.

I think that the current (and long standing) language of the various
specs can and has been interpreted both ways.

I agree, and I also agree that this should be changed.  I'm just not sure 
yet how.

Stuart D. Gathman wrote:
Scott Kitterman wrote:
a.  2.5.3.  Pass

   A "Pass" result means that the client is authorized to inject mail
   with the given identity.  Further determnination is required to
   find out if the message is authentic before policy checks, such as
   reputation, or black and/or white listing, can proceed.

b.  2.5.3.  Pass

   A "Pass" result means that the client is authorized to inject mail
   with the given identity and that the message may be treated as
   authentic.  Further policy checks, such as reputation,    or black
   and/or white listing, can now proceed with confidence in the
   identity.

[...]
PASS is meaningless unless it is option b - so that is the only option
I can support.  A NEUTRAL result already gives you the equivalent of
option a.

No, "Neutral" is _not_ some kind of "SoftPass".  "Neutral" means "I won't 
tell you whether I have authorized this system to use my identity when 
sending mail".  Yes, I know this sounds stupid, but that's what some 
people want to be included in the specification, so there you are.

And, again, I don't think it makes much sense to distinguish between 
"authorized" and "authentic" in practice.  SPF policies are all about 
taking responsibility for certain mail, and this is what actually counts.
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