DOC: config: mention other responses not blocked by option checkcache

The doc for "option checkcache" forgot to mention that responses with
no validator nor object freshness info are not considered and can pass
unfiltered to the client (it's because these info were developed with
the cache that didn't exist when the option was developed).

diff --git a/doc/configuration.txt b/doc/configuration.txt
index beb11b2ce99f83903ae8daad1f999162274e4efb..7984fd4235a62a9a7b784b0f84e9777e31101e90 100644 (file)
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -10299,6 +10299,10 @@ no option checkcache
     - those with a 'Cache-control: no-cache="set-cookie"' header
     - those with a 'Cache-control: no-cache="set-cookie,' header
       (allowing other fields after set-cookie)
+    - those which carry neither freshness information ("Cache-control" with a
+      "max-age" or an "s-maxage", or an "Expires" header) nor a validator (an
+      "ETag" or a "Last-Modified" header), since such a response is not
+      stored by a compliant cache.
 
   If a response doesn't respect these requirements, then it will be blocked
   just as if it was from an "http-response deny" rule, with an "HTTP 502 bad