Re: [squid-users] Squid and HTTP/1.1 303 See other

On 03/02/11 23:18, Jean-Baptiste Denis wrote:
> Hello everybody,
>
> simplistic description of my problem : squid seems confused when
> receiving a HTTP/1.1 303 error code.
>
> Here is the full description : i've got a http client (157.99.64.54)
> accessing a toshiba printer web interface (france.hopital.pasteur.fr /
> 157.99.176.25).
>
> When my client (firefox) connect to france.hopital.pasteur.fr WITHOUT
> using squid, everything is fine There is a
> redirection after the HTTP/1.1 303 to 157.99.176.25:8080 (see
> firefox-direct.pcap). I can see it in my adress bar and i access to the
> web interface.
>
> When my client connect to france.hopital.pasteur.fr THROUGH squid, i've
> got this error :
>
> "Invalid Response error was encountered while trying to process the request:
>
> GET / HTTP/1.1
> Host: france.hopital.pasteur.fr
> User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.1.15)
> Gecko/20101028 Iceweasel/3.5.15 (like Firefox/3.5.15)
> Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
> Accept-Language: en-us,en;q=0.5
> Accept-Encoding: gzip,deflate
> Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
> Keep-Alive: 300
> Proxy-Connection: keep-alive
> "
>
> The corresponding pcap file is firefox-squid.pcap. I've got a HTTP/1.0
> 502 Bad Gateway. The corresponding pcap file on the squid side is
> squid-toshiba.pcap. I can see the HTTP/1.1 303, but nothing else.
>
> If i use http://157.99.176.25 it does not work either, but if i specify
> the port (http://157.99.176.25:8080) i've got no problem.
>
> Chrome/Chromium seems to encounter the same problem. I try to connect to
> http://france.hopital.pasteur.fr WITHOUT squid, i've got the same
> behaviour (and similar pcap file) : i receive HTTP/1.1 303 and nothing
> else append.
>
> The pcap files:
>
> http://dl.pasteur.fr/fop/AjvBeYu8/firefox-direct.pcap
> http://dl.pasteur.fr/fop/XwBDAABP/firefox-squid.pcap
> http://dl.pasteur.fr/fop/jhQdWnsD/squid-toshiba.pcap
>
> Any hints is welcome :)

Both your pcap files show that the 303 response headers contains:

"

HTTP/1.1 303 See Other
Location: http://157.99.176.25:8080
  Feb 2011 11:51:08 GMT
Content-Length: 0

"

According to HTTP whitespace un-wrapping rules that makes the URL:

   http://157.99.176.25:8080 Feb 2011 11:51:08 GMT

This makes me worried about why Firefox is accepting this.

That very small 303 reply was broken into no less than 8 TCP fragments
so something in the hardware chain has an extremely small MTU of around
9 bytes per packet.

Amos

-- 
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   Current Stable Squid 2.7.STABLE9 or 3.1.10
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