GeekLab

Step 1: Install squid

yum -y install squid

Step 2: Configure squid

acl manager proto cache_object acl localhost src 127.0.0.1/32 ::1 acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1 # 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 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 # Here I define the times and what file contains the rules acl playtime1 time SMTWHFA 8:30-9:30 acl playtime22 time SMTWHFA 16:00-17:00 acl addiction url_regex -i "/etc/squid/addiction" # Only allow cachemgr access from localhost http_access allow manager localhost http_access deny manager # Deny requests to certain unsafe ports http_access deny !Safe_ports # Deny CONNECT to other than secure SSL ports http_access deny CONNECT !SSL_ports # 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 # # The next few lines actually do the work http_access allow playtime1 addiction http_access allow playtime2 addiction http_access deny addiction # If this ACL is triggered, show the user the WORKONLY error message. deny_info WORKONLY addiction # 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 http_access allow localnet http_access allow localhost # And finally deny all other access to this proxy http_access deny all # Squid normally listens to port 3128 # I added the word "transparent", so squid behaves a little different: # it makes itself transparent. NOTE TO SELF: This is the line you're looking for. Used to be httpd_accel_uses_host_header in squid 2 http_port 3128 transparent # We recommend you to use at least the following line. hierarchy_stoplist cgi-bin ? # Uncomment and adjust the following to add a disk cache directory. #cache_dir ufs /var/spool/squid 100 16 256 # Leave coredumps in the first cache dir coredump_dir /var/spool/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 # Don't show squid to the outside world forwarded_for delete # I don't need to log what she's doing access_log none # Nor do i need icap logs icap_log none # And i don't want to know what is stored in cache cache_store_log none # To not break web apps, I don't want caching either cache deny all

Step 3: Define blocked sites

Step 4: Leave a message

Step 5: Route network traffic

#Allow user 'root' to surf the web, for yum update etc.
iptables -t nat -A OUTPUT -m tcp -p tcp --dport 80 -m owner --uid-owner root -j RETURN
# Allow user 'squid' to pass on http requests
iptables -t nat -A OUTPUT -m tcp -p tcp --dport 80 -m owner --uid-owner squid -j RETURN
# Redirect all other traffic to the proxy.
iptables -t nat -A OUTPUT -m tcp -p tcp --dport 80 -j REDIRECT --to-ports 3128