Re: Possible bug?

This very much sounds like a non RFC 1738 compliant (or Netscape style)
FTP url.

There are two kinds of URLs which are correct for this resource:
1. Skip pub/ from the url (only works with RFC compliant
browsers/proxies)
ftp://usergroup@vnmrnews.nmr.varian.com/userlib/psglib/ProteinPack.tar.Z
2. Encode a leading / character in the path (works with close to
everything)
ftp://usergroup@vnmrnews.nmr.varian.com/%2f/pub/userlib/psglib/ProteinPack.tar.Z
or
ftp://usergroup@vnmrnews.nmr.varian.com/%2fpub/userlib/psglib/ProteinPack.tar.Z

The URL
ftp://usergroup@vnmrnews.nmr.varian.com/pub/userlib/psglib/ProteinPack.tar.Z
is the same as the following FTP sequence:
Open vnmrnews.nmr.varian.com
USER usergroup
PASS xxxxxx
CWD pub
CWD userlib
CWD psglib
RETR ProteinPack.tar.Z

But Netscape "optimizes" it to

Open vnmrnews.nmr.varian.com
USER usergroup
PASS xxxxxxx
RETR /pub/userlib/psglib/ProteinPack.tar.Z

Which is wrong since
A) In includes a leading / character
B) It only works reliabely with UNIX based FTP servers. Do this on a
VMS, TOPS or any other odd server and it will choke.

Squid 2 contains a few automated hacks to lessen the burden on the end
user from this URL confusion. It automatically falls back on a leading /
when retreiving files, and shows a appropriate message to the end user
when trying to retreive directories.

---
Henrik Nordstrom
Spare time Squid hacker
David Howse wrote:
> 
> Hi there
> 
> One of our users is experiencing the following problem.
> 
> >>I've been exchanging email with someone at Varian U.S.A. regarding
> >>difficulties downloading a file by ftp using Nestcape. The URL on their
> >>web page is
> >>
> >>ftp://usergroup@vnmrnews.nmr.varian.com/pub/userlib/psglib/ProteinPack.tar.Z
> >>
> >>This gives an error that the file doesn't exist if I try it from the ANU,
> >>but is OK from home via [ISP name]. However if I leave out the "pub", it
> >>works properly from the ANU. Following a suggestion from the Varian
> >>person, I turned off automatic proxy configuration in Netscape, and the
> >>correct URL (with "pub") started working from the ANU.
> 
> Is there a problem with squid processing strangely-formed URLs?  We've
> never seen the problem before.
> 
> We're using v1.1.21.
> 
> Any advice you can give would be most enlightening.
> 
> David
> 
> David Howse                     Mail:  David.Howse@anu.edu.au
> Network Services - Systems      Phone: +61 2 6249 3583
> IT Services                     Fax:   +61 2 6279 8199
> Australian National University  http://netserve.anu.edu.au/staff/david.howse