bug#43566: 27.1; url-http and excorporate does not authenticate

[Thomas Fitzsimmons]

Hi Lars,

Lars Ingebrigtsen <larsi@gnus.org> writes:

> Thomas Fitzsimmons <fitzsim@fitzsim.org> writes:
>
>> I no longer use the NTLM mode myself, but I did manage to independently
>> figure out the issue by implementing an NTLM server in elisp.  I'm going
>> to add it to the test suite, since otherwise it's not feasible for Emacs
>> maintainers to test ntlm.el properly (which is what happened in Emacs
>> 27.1).  I can test inflooping against it too once I have the changes
>> ready.
>
> Great!

I've got an initial version of the test running locally.  There's still
a lot of integration to do, which I probably won't finish before Emacs
27.2.  I'd like to put in a workaround for now.

How about this patch for the emacs-27 branch?  Is there a test suite
entry for bug 27022 that I can run against my elisp NTLM server?

Thanks,
Thomas

diff --git a/lisp/url/url-http.el b/lisp/url/url-http.el
index 298f204791..89d2189ad1 100644
--- a/lisp/url/url-http.el
+++ b/lisp/url/url-http.el
@@ -461,8 +461,10 @@ url-http-handle-authentication
     ;; headers, then this means that we've already tried sending
     ;; credentials to the server, and they were wrong, so just give
     ;; up.
-    (when (assoc "Authorization" url-http-extra-headers)
-      (error "Wrong authorization used for %s" url))
+    (let ((authorization (assoc "Authorization" url-http-extra-headers)))
+      (when (and authorization
+                (not (string-match "^NTLM " (cdr authorization))))
+       (error "Wrong authorization used for %s" url)))
 
     ;; find strongest supported auth
     (dolist (this-auth auths)