Re: [PATCH] http(s): automatically try NTLM authentication first

[Junio C Hamano <gitster@pobox.com>]

Jeff King <peff@peff.net> writes:

> On Wed, Feb 22, 2017 at 01:57:28PM -0800, Junio C Hamano wrote:
>
>> Jeff King <peff@peff.net> writes:
>> 
>> > On Wed, Feb 22, 2017 at 01:25:11PM -0800, Junio C Hamano wrote:
>> >> 
>> >> Thanks for your thoughts.  I'd think that we should take this change
>> >> and leave the optimization for later, then.  It's not like the
>> >> change of the default is making the normal situation any worse, it
>> >> seems.
>> >
>> > I'm not excited that it will start making known bogus-username requests
>> > by default to servers which do not even support Negotiate. I guess that
>> > is really the server-operators problem, but it feels pretty hacky.
>> 
>> I guess that's another valid concern.  The servers used to be able
>> to say "Ah, this repository needs auth and this request does not, so
>> reject it without asking the auth-db".  Now it must say "Ah, this
>> repository needs auth and this request does have one, but it is
>> empty so let's not even bother the auth-db" in order to reject a
>> useless "empty-auth" request with the same efficiency.
>> 
>> After the first request without auth (that fails), do we learn
>> anything useful from the server side (like "it knows Negotiate")
>> that we can use to flip the "empty-auth" bit to give a better
>> default to people from both worlds, I wonder...?
>
> Yes, that's exactly what I was trying to say in my first message.

I see.  I am still inclined to take this as-is for now to cook in
'next', though.  

A solution along your line would help Negotiate users OOB experience
without hurting the servers that do not offer Negotiate, but until
that materializes, users can set the lazier http.emptyAuth on
(without selectively setting http.<host>.emptyAuth off for sites
without Negotiate) and hurt the servers by throwing an empty auth
anyway regardless of the default, so the flipping of the default is
not fundamentally adding more harm in that sense.