file extension ACLs and choosing parents

Hi All

If I set up a list of file extensions into an ACL, is there any way of
configuring Squid to use one specific parent for any entry that matches this
ACL, but use the normal configured weighted parents for everything else?

e.g.

====

#List of file extentions
acl file-ext urlpath -i \.exe$ \.zip$ \.tar$

#List of AntiVirus Checking proxy parents (I know this acl type doesnt
exist!)
acl antivirus-parent parent-list 1.2.3.4:8080 5.6.7.8:8080

#force all file extensions in file-ext to use parents in antivirus-parent
list
http_access allow file-ext parent-list

====

The closest thing I could find was a never_direct/always_direct system, but
that doesnt cope with the multiple failover system we have here. We proxy
chain from squid to 1 of 3 firewalls we have, but want to insert WebSweeper
to Virus check certain filetypes.

Any thoughts on how in implement a CLI based AntiVirus scanner into Squid?
mmm... it would need to scan the entire file before it hands it back to the
client, so the client wouldnt get any of the file until squid had received
the entire file... so squid would need to create updating HTML to show the
current download status for the item (so that the browser wouldnt time out
the connection)... on second thoughts, lets not get into this one, it could
get messy :)

Any help would be greatly appreciated.

--
Steve
-------------------------------------------------
Steve Loughran, Network Infrastructure Manager
Sony Computer Entertainment Europe (Cambridge)
http://camsg001.millennium.co.uk/index.htm
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