Hi, I am having trouble setting up a Squid Interception/transparent proxy server. I am using Ubuntu Server Edition 12.10, Squid 3.3 and a DD-WRT Router to redirect traffic to the proxy. The script I am using I got at this link: http://www.dd-wrt.ca/wiki/index.php/Squid_Transparent_Proxy
My exact iptables script is (from that link): #!/bin/sh PROXY_IP=192.168.0.10 PROXY_PORT=3127 LAN_IP=`nvram get lan_ipaddr` LAN_NET=$LAN_IP/`nvram get lan_netmask` iptables -t nat -A PREROUTING -i br0 -s $LAN_NET -d $LAN_NET -p tcp --dport 80 -j ACCEPT iptables -t nat -A PREROUTING -i br0 -s ! $PROXY_IP -p tcp --dport 80 -j DNAT --to $PROXY_IP:$PROXY_PORT iptables -t nat -I POSTROUTING -o br0 -s $LAN_NET -d $PROXY_IP -p tcp -j SNAT --to $LAN_IP iptables -I FORWARD -i br0 -o br0 -s $LAN_NET -d $PROXY_IP -p tcp --dport $PROXY_PORT -j ACCEPT I have also tried to use PROXY_PORT 3128 (not 3127) also. I can successfully edit the PROXY_PORT to 80 (local Apache web server) and it works, no problem. My error message I am getting in /var/log/squid/cache.log is: TIME HERE kid1| NF getsockopt(SO_ORIGINAL_DST) failed on local=SERVER_IP:3127 remote=ROUTER_IP:62479 FD 20 flags=33: (92) Protocol not available In my browser I don't get any error message, just a blank page. I get this error message every request I try, though the port on the remote changes each time. My squid.conf is as follows: # # Recommended minimum configuration: # # Example rule allowing access from your local networks. # Adapt to list your (internal) IP networks from where browsing # should be allowed #acl localnet src 10.0.0.0/8 # RFC1918 possible internal network #acl localnet src 172.16.0.0/12 # RFC1918 possible internal network #acl localnet src 192.168.0.0/16 # RFC1918 possible internal network #acl localnet src fc00::/7 # RFC 4193 local private network range #acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines #HTTP header X-Forwarded-For forwarded_for transparent #Don't change header sent by client #VIA (sends proxy header) via off #Define error message directory error_directory /var/www/error #Log query string in access.log strip_query_terms off #Define log file locations access_log /var/log/squid/access.log cache_store_log /var/log/squid/store.log cache_log /var/log/squid/cache.log # Squid normally listens to port 3128 http_port 3128 http_port 3127 intercept acl SSL_ports port 443 # Normal SSL port for HTTPS acl SSL_ports port 8443 # Plesk SSL acl SSL_ports port 2083 # cPanel SSL acl Safe_ports port 80 # http acl Safe_ports port 83 # 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 # Deny requests to certain unsafe ports # Deny CONNECT to other than secure SSL ports # # Recommended minimum Access Permission configuration: # # Only allow cachemgr access from localhost # We strongly recommend the following be uncommented to protect innocent # web applications running on the proxy server who think the only # one who can access services on "localhost" is a local user #http_access deny to_localhost # # INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS # # Example rule allowing access from your local networks. # Adapt localnet in the ACL section to list your (internal) IP networks # from where browsing should be allowed acl localnet src 192.168.0.0/16 cache deny all http_access deny !Safe_ports http_access deny CONNECT !SSL_ports http_access allow localnet # And finally deny all other access to this proxy http_access deny all # Uncomment and adjust the following to add a disk cache directory. cache_dir ufs /var/cache/squid 100 16 256 # Leave coredumps in the first cache dir coredump_dir /var/cache/squid # Add any of your own refresh_pattern entries above these. refresh_pattern ^ftp: 1440 20% 10080 refresh_pattern ^gopher: 1440 0% 1440 refresh_pattern -i (/cgi-bin/|\?) 0 0% 0 refresh_pattern . 0 20% 4320 cache_effective_user proxy cache_effective_group proxy
