[WICKET-1777] Overflow when setting Expires header in WebResource

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 1.3.4, 1.4-M3
• Fix Version/s: 1.3.5, 1.4-RC1
• Component/s: wicket
• Assignee: Igor Vaynberg
• Reporter: Stefan Fussenegger
• Created: 06/Aug/08 13:00
• Updated: 06/Aug/08 15:27
• Resolved: 06/Aug/08 15:27

Description

problematic code:

response.setDateHeader("Expires", System.currentTimeMillis() + (getCacheDuration() * 1000));

getCacheDuration() * 1000 is an integer operation causing an overflow if getCacheDuration() is set to be > MAX_INT/1000 seconds (approx. 25 days) which is by far less than the w3c recommendation for "never expires":

"To mark a response as "never expires," an origin server sends an Expires date approximately one year from the time the response is sent. HTTP/1.1 servers SHOULD NOT send Expires dates more than one year in the future."
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.21

changing getCacheDuration() to return long or forcing a long operation fixes the problem:

response.setDateHeader("Expires", System.currentTimeMillis() + getCacheDuration() * 1000L);