Apache2 proxy seems to drop Content-Length header from replies to HEAD requests. This is very bad for Microsoft's Windows Update system (and against HTTP spec). The problem is caused by CONTENT_LENGTH output filter setting Content-Length header to zero because there is no body data. Later on Apache removes Content-Length header if it has value 0.
The attached patch fixes the problem in CONTENT_LENGTH output filter by preventing it from modifying the content length of a reply to HEAD request. The attached patch is against HEAD of APACHE_2_0_BRANCH as of this morning. -- Sami Tikka, senior software engineer, F-Secure Corporation tel: +358 9 2520 5115, fax: +358 9 2520 5015 http://www.F-Secure.com F-Secure: Securing the Mobile Enterprise
windows-update.diff
Description: windows-update.diff