[squid-users] Transparent proxy problem

Hi Squid users,

I'm trying to set Squid up to function as a transparent proxy without
success. I've got Squid 3 stable release 16. I'm running as root with
the cache_effective_user as squid (the owner of the squid directories
is squid).

I've setup iptables so that port 80 traffic gets sent to 3128 where
the client connects

iptables -t nat -A PREROUTING -i eth0 -p tcp --dport 80 -j REDIRECT
--to-port 3128

Firefox reports that the proxy refused connection. tcpdump indicates
that the proxy does receive some packets on 3128 and there are no
other obstructive firewall rules. I don't know a great deal about
iptables but should I also have a rule that sends requests received on
3128 out of port 80 to the requested web server? The rule above only
redirects retrieved pages, if I understand correctly?

Here is my squid.conf:

acl manager proto cache_object
acl localhost src 127.0.0.1/32
acl to_localhost dst 127.0.0.0/8
#client IP below
acl localnet src 10.112.0.221/32 # RFC1918 possible internal network
acl SSL_ports port 443
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 # https
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT

http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access deny to_localhost

http_access allow localnet

http_access deny all

icp_access allow localnet
icp_access deny all

htcp_access allow localnet
htcp_access allow all

http_port 3128 transparent

hierarchy_stoplist cgi-bin ?

access_log /usr/local/squid/var/logs/access.log squid

refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern (cgi-bin|\?) 0 0% 0
refresh_pattern . 0 20% 4320

cache_effective_user squid

icp_port 3130

coredump_dir /usr/local/squid/var/cache

Thanks.
Received on Mon Jun 22 2009 - 09:41:05 MDT