URL:
<http://savannah.gnu.org/bugs/?40819>
Summary: wget does not send Accept-Encoding and fails to
handle Content-Encoding
Project: GNU Wget
Submitted by: nok
Submitted on: Do 05 Dez 2013 22:28:45 CET
Category: Protocol Issue
Severity: 3 - Normal
Priority: 5 - Normal
Status: None
Privacy: Public
Assigned to: None
Originator Name:
Originator Email:
Open/Closed: Open
Discussion Lock: Any
Release: trunk
Operating System: GNU/Linux
Reproducibility: None
Fixed Release: None
Planned Release: None
Regression: None
Work Required: None
Patch Included: No
_______________________________________________________
Details:
Hello,
a forwarded bug from a Debian user: http://bugs.debian.org/731110
--8<--
I observed that wget downloads "wrong" content from a squid cache. Both tools
operate within the bounds of RFC2616, but the resulting combination is wrong.
Consider the following interaction:
A http client that supports Accept-Encoding and Content-Encoding
downloads an object via a squid3 proxy. An encoding that is not the identity
encoding is chosen and the response is considered cacheable by squid3. At a
later time wget is instructed to retrieve the same object via the same proxy.
Unlike the other client wget does not send an Accept-Encoding header. The
squid3 proxy exercises an assumption explicitly granted by RFC2616 14.3:
| If no Accept-Encoding field is present in a request, the server MAY
| assume that the client will accept any content coding.
It thus sends back the cached object including the Content-Encoding header,
but wget does not handle the header and stores the object in compressed form.
Note that RFC2616 goes on to say:
| In this case, if "identity" is one of the available content-codings,
| then the server SHOULD use the "identity" content-coding, unless it has
| additional information that a different content-coding is meaningful to
| the client.
So arguably squid3 is violating a SHOULD clause and should be fixed.
A simple mechanism to resolve the situation is to make wget send an empty
Accept-Encoding header by default or setting its value to "identity".
Helmut
--8<--
Thank you.
_______________________________________________________
Reply to this item at:
<http://savannah.gnu.org/bugs/?40819>
_______________________________________________
Nachricht gesendet von/durch Savannah
http://savannah.gnu.org/
--
To UNSUBSCRIBE, email to debian-bugs-dist-requ...@lists.debian.org
with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org
