Fix for Proxy server authentication without credentials available.

Fix for Proxy server authentication without credentials available.

This covers the cases using GSSAPI for Negotiate to authenticate to a proxy, where:

- The user does not have a TGT (Ticket Generating Ticket), or
- The user is unable to get to the TGS (Ticket Granting Server).

The bug was that the authentication system tried to reuse the Negotiate handler even though it was not possible for it to succeed, leading to infinite retries.

BUG=33033
Test=None

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=53819

[cbentzel, 2010-07-23 17:05:48]

I tried this on my machine yesterday and it does fix the issue.

However, you should make the description of this CL clearer. Mentioned something
about if the user does not have a TGT when attempting an authenticate challenge,
or that they are unable to retrieve the TGS of the server they are trying to
authenticate to.

Also, there should be a unit test, and the test description should include
something like "Set chrome to go to a Kerberized proxy, call kdestroy (and make
sure the TGT is gone using klist), and see that Chrome degrades to a
non-Negotiate authentication scheme if one is available instead of infinitely
looping"

[wtc, 2010-07-23 18:20:50]

LGTM.

http://codereview.chromium.org/3040015/diff/1/2
File net/http/http_auth.cc (right):

http://codereview.chromium.org/3040015/diff/1/2#newcode62
net/http/http_auth.cc:62: if (disabled_schemes.find(cur->scheme()) ==
disabled_schemes.end())
Can you take the opportunity to replace the inner "if" with "&&"?

[ahendrickson, 2010-07-27 15:06:54]

http://codereview.chromium.org/3040015/diff/1/2
File net/http/http_auth.cc (right):

http://codereview.chromium.org/3040015/diff/1/2#newcode62
net/http/http_auth.cc:62: if (disabled_schemes.find(cur->scheme()) ==
disabled_schemes.end())
On 2010/07/23 18:20:51, wtc wrote:
> Can you take the opportunity to replace the inner "if" with "&&"?

Done.

[cbentzel, 2010-07-27 15:30:16]

LGTM.

As we discussed, please land this first so it can get into the mstone6 branch
and continue to write unit tests on the side.