protocol/5411: probably missing test in If-Modified-Since code

[Martin DEVERA <de...@cdi.cz>]

>Number:         5411
>Category:       protocol
>Synopsis:       probably missing test in If-Modified-Since code
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    apache
>State:          open
>Class:          sw-bug
>Submitter-Id:   apache
>Arrival-Date:   Fri Dec  3 03:40:00 PST 1999
>Last-Modified:
>Originator:     devik@cdi.cz
>Organization:
apache
>Release:        1.3.9
>Environment:
Linux RH 6.1 .. doesn't matter	
>Description:
Suppose you have apache on IP and only one global web (with "It worked..").
Someone looked it via SQUID proxy which cached the / dir. Then we created
virtual web on the same IP. The same person looked again but it have seen
the same old page. When I traced it using sniffit I found that SQUID sends
request with If-Modified-Since header with date 11/8 and length=1945.
New index.html was older but has DIFFERENT LENGTH. It seems the Apache tests
ONLY date and when file-date is older it doesn't check file length too.
It's not too serious bug, but probably it can make some headaches ..	
>How-To-Repeat:
see above
>Fix:
Yep. Test for file length difference before sending 304 response ..
>Audit-Trail:
>Unformatted:
[In order for any reply to be added to the PR database, you need]
[to include <ap...@Apache.Org> in the Cc line and make sure the]
[subject line starts with the report component and number, with ]
[or without any 'Re:' prefixes (such as "general/1098:" or      ]
["Re: general/1098:").  If the subject doesn't match this       ]
[pattern, your message will be misfiled and ignored.  The       ]
["apbugs" address is not added to the Cc line of messages from  ]
[the database automatically because of the potential for mail   ]
[loops.  If you do not include this Cc, your reply may be ig-   ]
[nored unless you are responding to an explicit request from a  ]
[developer.  Reply only with text; DO NOT SEND ATTACHMENTS!     ]