Tag Archives: proxy

Ad block with Squid3 and Quintolabs instead of Adblock Plus


Under the twitter hashtag #adblockgate you find news related to the business of the company behind the adblock plus browser plugin for chrome or firefox.

The problem with their business is the secret white list which serve you ads without a chance to avoid them.

The advantage of this solution here is to have a central ad blocking service for all of your devices including smart phones and tablets.

Used Software (under ubuntu 13.04):

  • Apache Httpd (for serving the pac file)
  • Squid3 (as primary proxy)
  • Quintolabs (as  ICAP Server for ad blocking)

Install Apache Httpd

apt-get install apache2

Install Squid3

apt-get install squid3

Install Quintolabs

open Download page and choose deb File and run the command (as root)

dpkg -i qlproxy-2.0.0.d746b-ubuntu_i386.deb

Create PAC File for the web clients

Change <your ubuntu host ip> with the ip of your server

nano /var/www/proxy.pac

function FindProxyForURL(url, host) {
// avoid anti virus update problems
if (shExpMatch(host,"*.bitdefender.com")) {
return "DIRECT";

// avoid anti virus update problems
if (shExpMatch(host,"*.bitdefender.net")) {
return "DIRECT";
// avoid proxy for URLs inside your network
if (isInNet(host, "", "")) {
return "DIRECT";

// the rest goes through your proxy
return "PROXY <your ubuntu host ip>:3128";

Configure Squid3

nano /etc/squid3/squid.conf

acl manager proto cache_object
acl localhost src ::1
acl to_localhost dst ::1
acl localnet src # 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
http_access allow all
http_access allow manager localhost
http_access deny manager
http_access deny !Safe_ports
http_access deny CONNECT !SSL_ports
http_access allow localhost
http_access deny all
http_port 3128
cache_mem 768 MB
maximum_object_size_in_memory 1024 KB
memory_replacement_policy heap GDSF
cache_replacement_policy heap LFUDA
pid_filename /var/run/squid3.pid
buffered_logs on
coredump_dir /var/spool/squid3
refresh_pattern ^ftp:           1440    20%     10080
refresh_pattern ^gopher:        1440    0%      1440
refresh_pattern -i (/cgi-bin/|\?) 0     0%      0
refresh_pattern (Release|Packages(.gz)*)$      0       20%     2880
refresh_pattern .               0       20%     4320
negative_dns_ttl 5 minutes
via off
ignore_expect_100 on
forward_timeout 30 seconds
connect_timeout 30 seconds
read_timeout 30 seconds
request_timeout 30 seconds
persistent_request_timeout 1 minutes
client_lifetime 20 hours
dns_timeout 5 minutes
ipcache_size 10240
forwarded_for delete
client_db off
acl home_network src
icap_enable on
icap_preview_enable on
icap_preview_size 4096
icap_persistent_connections on
icap_send_client_ip on
icap_send_client_username on
icap_client_username_header X-Client-Username
icap_service qlproxy1 reqmod_precache bypass=0 icap://
icap_service qlproxy2 respmod_precache bypass=0 icap://
adaptation_access qlproxy1 allow all
adaptation_access qlproxy2 allow all

Patch Quintolabs

To use own ad block lists change the settings file

nano /opt/quintolabs/qlproxy/bin/settings.py

adblock = {
“DataDir” : macro_var + “/spool/adblock”,
“DataFiles” : {
“easylist.txt” : “https://easylist-downloads.adblockplus.org/easylist.txt”,
“easyprivacy.txt” : “https://easylist-downloads.adblockplus.org/easyprivacy.txt”,
“easylistgermany.txt” : “https://easylist-downloads.adblockplus.org/easylistgermany.txt”,
“fanboy-russian.txt” : “https://secure.fanboy.co.nz/fanboy-russian.txt”,
“own-adblock.txt” : “http://ralf.schaeftlein.com/adblock-plus.txt”

own-adblock.txt can be used as alias for own ad block subscriptions. See further configuration below.

Change the validation of ad block lists to avoid verification errors with different headers

nano /opt/quintolabs/qlproxy/bin/update_adblock.py

change verify function line to this

if re.search(r’\[Adblock\s+Plus’, line) != None:

Configure Quintolabs

Enable ad block module in the global config

nano /etc/opt/quintolabs/qlproxy/qlproxyd.conf

adblock_enabled = yes

and disable the other modules

urlblock_enabled = no
httpblock_enabled = no
contentblock_enabled = no
adultblock_enabled = no

Enable relaxed module for your subnet

nano /etc/opt/quintolabs/qlproxy/policies/relaxed/members.conf

Change the last line to (assuming is the network subnet of your clients)

user_ip_subnet =

set pass through domains for your antivirus tool by editing

nano /etc/opt/quintolabs/qlproxy/policies/relaxed/exceptions.conf

Change the lines with domain name for your needs like this for bitdefender

# disable filtering for all third level domains of the following servers
domain_name = .microsoft.com
domain_name = .quintolabs.com
domain_name = .bitdefender.com
domain_name = .bitdefender.net

Enable all ad block subscriptions

nano /etc/opt/quintolabs/qlproxy/policies/relaxed/rules/block_ads.conf

use_subscription = easylist.txt
use_subscription = easylistgermany.txt
use_subscription = fanboy-russian.txt
use_subscription = easylist_custom.txt
use_subscription = easyprivacy.txt
use_subscription = own-adblock.txt

Restart Quintolabs to read change configs

/etc/init.d/qlproxy restart

Update ad block list for the first time


Restart Quintolabs to read change ad block lists

/etc/init.d/qlproxy restart

Restart web and proxy server

restart squid3

service apache2 restart

Configure windows browser

  1. Start internet explorer and open settings.
  2. Go to connection tab
  3. click on lan settings
  4. click second checkbox for “script for automatic configuration” and enter (replace <servername> with your ubuntu hostname)http://<servername>/proxy.pac
  5. Confirm dialog with ok and close settings with ok
  6. Restart all browsers

This affect chrome and internet explorer.

Under Firefox

  1. open settings
  2. go to advanced
  3. go to network
  4. Click on connections
  5. Set the last line to the same url as step 4 from above and click on the radiobox over the url for “automatic proxy configuration url”
  6. Click on “reload” button beside the url text field

Remove existing browser plugins

Uninstall chrome and firefox adblock plus plugins

Set proxy under android for the wlan

  1. Open settings 
  2. Click on wlan (which is enabled)
  3. Hold the entry with your ssid pressed
  4. Choose from menu “change network setttings”
  5. Click on checkbox “show extended settings”
  6. Choose “manual” as proxy settings
  7. Choose <servername> (like in the url above) as proxy hostname
  8. Choose “3128” as proxy port
  9. Click on save button

Test ad block

Open web pages like the following to see if the ad banners are removed by the proxy server



Check if proxy can be detected by external web sites

Sample sites which looks for http header in the request to see if you are coming via a proxy


“Proxy server not detected.”


“This request appears NOT to have come via a proxy.”

Get rid of annoying SHIFT-R and SHIFT-A hints on images

Either Vodafone and T-Mobile use hidden picture compressions and remove alt text inside web pages when you surf with a UMTS stick. The traffic goes through a transparent proxy with that “feature”. Pictures inside browsers have less quality. Most annoying for me is that if you browse on geocaching.com for Geocaches on a map. You see normally the name of the cache if your mouse goes over the cache icon on the map. With a mobile internet connection you see a hint that “Shift-R improves quality of that picture and SHIFT-A improves the quality of all picture on that page”. A solution for this is a firefox plugin called: “Modify Headers“. Go to the extras menu and open “Modify Headers” entry. Enter a new rule and in the first field (Name) “Cache-Control” and in the second field “no-cache” (Value). Save the rule and enable them. Restart the browser. Now reopen with firefox a page with pictures. Quality as with normal internet connections and no more annoying hints to improve quality. In geocaching.com maps will now the name of the cache presented as expected.