Bug 27214 - NTLM Authentication fails when KeepAlive == false
Summary: NTLM Authentication fails when KeepAlive == false
Alias: None
Product: Class Libraries
Classification: Mono
Component: System.Net.Http ()
Version: 3.12.0
Hardware: PC All
: --- normal
Target Milestone: Untriaged
Assignee: Bugzilla
Depends on:
Reported: 2015-02-19 09:25 UTC by Lukasz Kulisz
Modified: 2015-02-20 11:21 UTC (History)
2 users (show)

Is this bug a regression?: ---
Last known good build:

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Description Lukasz Kulisz 2015-02-19 09:25:36 UTC
NTLM requires connection to be maintained after successful authentication. 

At the moment, when client sets KeepAlive to false on an instance of HttpWebRequest, then the request will fail with 401 error, because after the successful handshake connection will be closed. This happens, because HttpWebRequest always sets 'Connection: Close' header when KeepAlive == false. 

.NET on Windows omits this header in the second step of NTML auth, even when KeepAlive is set to false.

Setting KeepAlive to false may help when connecting through certain types of proxies. 

I have implemented a simple fix for this issue along with updated tests, and submitted it as a pull request:
Comment 1 Miguel de Icaza [MSFT] 2015-02-20 11:21:01 UTC
Thanks for the pull request and the included tests.