Ad blocking

From DD-WRT Wiki

(Difference between revisions)
Jump to: navigation, search
Revision as of 19:56, 9 October 2013 (edit)
Gohat (Talk | contribs)
(Ad Blocking with builds other than Micro)
← Previous diff
Revision as of 20:00, 9 October 2013 (edit) (undo)
Gohat (Talk | contribs)
(Ad Blocking with builds other than Micro)
Next diff →
Line 40: Line 40:
You may took alternately this script. You may took alternately this script.
Just put this script into "Firewall". Just put this script into "Firewall".
-Ensure cron is enabled.+Ensure cron is enabled. A cron entry is automatically generated at start-up.
<pre> <pre>

Revision as of 20:00, 9 October 2013

Ad Blocking with builds other than Micro

This script, courtesy of several people on the forums, who probably should be named, will enable host-based ad blocking via dns.

Maybe this script will not work on every device or it might crash your router when ther is not enough free ram.

Just put this script into "Startup":

#!/bin/sh
logger WAN up script executing
if test -s /tmp/hosts0
then
        rm /tmp/hosts0
fi

logger Downloading http://www.mvps.org/winhelp2002/hosts.txt
wget -O - http://www.mvps.org/winhelp2002/hosts.txt | grep 127.0.0.1 |
	sed '2,$s/127.0.0.1/0.0.0.0/g; s/[[:space:]]*#.*$//g;' |
	grep -v localhost | tr ' ' '\t' |
	tr -s '\t' | tr -d '\015' | sort -u >/tmp/hosts0
grep addn-hosts /tmp/dnsmasq.conf ||
	echo "addn-hosts=/tmp/hosts0" >>/tmp/dnsmasq.conf
logger Restarting dnsmasq
killall dnsmasq
dnsmasq --conf-file=/tmp/dnsmasq.conf

...and this into cron:

0 12 * * * root /tmp/.rc_startup

Enable DNSMasq and Local DNS in Services tab; no Additional DNSMasq options necessary.

Ensure cron is enabled.

You may took alternately this script. Just put this script into "Firewall". Ensure cron is enabled. A cron entry is automatically generated at start-up.

# --- COPY THE TEXT BELOW TO DD-WRT / ADMINISTRATION / COMMANDS then click SAVE FIREWALL ---
BH_SCRIPT="/tmp/blocking_hosts.sh"
logger "Download blocking hosts file and restart dnsmasq ..."
# Create download script.
cat > "$BH_SCRIPT" <<EOF
#!/bin/sh
# Function: clean_hosts_file [file ...]
clean_hosts_file() {
  sed -e '/^127.0.0.1/b replace;
          /^0.0.0.0/b replace;
          :drop;
            d; b;
          :replace;
            s/^127.0.0.1/0.0.0.0/;
            s/[[:space:]]*#.*\$//;
            s/[[:space:]]*\$//;
            s/[[:space:]][[:space:]]*/ /;
            /^0.0.0.0[[:space:]]localhost\$/b drop;' \$*
}
# Set lock file.
LOCK_FILE="/tmp/blocking_hosts.lock"
# Check lock file.
if [ ! -f "\$LOCK_FILE" ]; then
  sleep \$((\$\$ % 5 + 5))
  [ -f "\$LOCK_FILE" ] && exit 0
  echo \$\$ > "\$LOCK_FILE"
  # Wait for an Internet connection.
  while :; do
    ping -c 1 -w 10 www.freebsd.org > /dev/null 2>&1 && break
    sleep 10
  done
  # Start downloading files.
  HOSTS_FILE_NUMBER=1
  [ -d "/tmp/blocking_hosts" ] || mkdir "/tmp/blocking_hosts"
  for URL in "http://winhelp2002.mvps.org/hosts.txt" \\
             "http://someonewhocares.org/hosts/zero/hosts" \\
             "http://jansal.googlecode.com/svn/trunk/adblock/hosts" \\
             "http://adblock.gjtech.net/?format=hostfile" \\
             "http://www.hostsfile.org/Downloads/hosts.txt"; do
    HOSTS_FILE="/tmp/blocking_hosts/hosts\`printf '%02d' \$HOSTS_FILE_NUMBER\`"
    logger "Downloading \$URL ..."
    REPEAT=1
    while :; do
      START_TIME=\`date +%s\`
      # Create process to download a hosts file.
      wget -O - "\$URL" 2> /dev/null > "\${HOSTS_FILE}.tmp" &
      WGET_PID=\$!
      WAIT_TIME=\$((\$REPEAT * 10 + 20))
      # Create timeout process.
      ( sleep \$WAIT_TIME; kill -TERM \$WGET_PID ) &
      TIMEOUT_PID=\$!
      wait \$WGET_PID
      CURRENT_RC=\$?
      kill -KILL \$TIMEOUT_PID
      STOP_TIME=\`date +%s\`
      if [ \$CURRENT_RC = 0 ]; then
        clean_hosts_file "\${HOSTS_FILE}.tmp" > "\$HOSTS_FILE"
        rm "\${HOSTS_FILE}.tmp"
        break
      fi
      # In the case of an error: wait the remaining time.
      TIME_SPAN=\$((\$STOP_TIME - \$START_TIME))
      WAIT_TIME=\$((\$WAIT_TIME - \$TIME_SPAN))
      [ \$WAIT_TIME -gt 0 ] && sleep \$WAIT_TIME
      # Increase the number of repeats.
      REPEAT=\$((\$REPEAT + 1))
      [ \$REPEAT = 4 ] && {
        CURRENT_RC=1
        break
      }
    done
    HOSTS_FILE_NUMBER=\$((\$HOSTS_FILE_NUMBER + 1))
  done
  # Inspect downloaded hosts files.
  ANY_FILE_OK=1
  DNSMASQ_PARAM=""
  for HOSTS_FILE in /tmp/blocking_hosts/hosts[0-9][0-9]; do
    if [ -s "\$HOSTS_FILE" ]; then
      ANY_FILE_OK=0
      DNSMASQ_PARAM=\${DNSMASQ_PARAM:+\$DNSMASQ_PARAM }"--addn-hosts=\$HOSTS_FILE"
    else
      rm "\$HOSTS_FILE"
    fi
  done
  if [ \$ANY_FILE_OK = 0 ]; then
    logger "Restarting dnsmasq with additional hosts file(s) ..."
    killall -TERM dnsmasq
    dnsmasq --conf-file=/tmp/dnsmasq.conf \$DNSMASQ_PARAM &
  fi
  rm "\$LOCK_FILE"
fi
EOF
# Make it executeable.
chmod 755 "$BH_SCRIPT"
# Add crontab entry.
grep -q "$BH_SCRIPT" /tmp/crontab || echo "$(($$ % 60)) 3 * * * root $BH_SCRIPT" >>/tmp/crontab
# Execute script in background.
sh "$BH_SCRIPT" &

You may add other URLs to the list. You may be inspired by Ad-Away. See: Ad-Away-Wiki. Keep in mind: your routers memory limits.

Ad Blocking with Micro build

The Micro build does not support Journaling Flash File System (JFFS and JFFS v. 2). Because of this, the router can be instructed to block ads (though a hosts file) only on a temporary basis. The hosts file can only be written to temporary memory that is lost with each reboot.

As soon as the router is rebooted, loses electrical power, or is restarted with new settings, you must complete the steps below again, in order to again begin ad blocking.

Unfortunately, the Micro build also does not include most functional commands of the Busybox system, including features that would allow the router to automatically download an updated hosts file itself through a startup script (e.g., the wget command), so you must do it manually. Finally, the Micro build does not include SSH capability, so you must transfer the content of the hosts file by manually pasting it into the router's hosts file through a telnet window, instead of SSH-uploading it to the router.

Steps

1. Download the newest update of a trusted hosts file, such as from MVPS.org at: http://winhelp2002.mvps.org/hosts.txt

2. Open the hosts text file in Notepad, TextEdit, or Notepad++, or another text editor. Highlight all the text in the file and copy it.

3. Go to your router's web interface through your web browser, typically by entering the URL http://192.168.1.1. If you assigned your router a different local IP address, use that instead.

4. In the web interface, click on the Services tab. Enter your DD-WRT router username and password, if prompted.

5. Scroll down to the 'DNSMasq' section. Make sure that DNSMasq bullet and Local DNS bullets are set to 'Enable' that no other DNSMasq options are set.

6. Use Putty or another Telnet client to connect to the router's Telnet interface. (That is, connect to the router's local IP address on port 23 - telnet.)

7. Enter your login and password. The password will be the same as for the web interface. For the username, first try root. If that does not work, try the same username as for the web interface.

8. At the DD-WRT command prompt, type killall DNSMasq and hit enter.

9. Type pwd and hit enter. You should get back "/tmp/root". Type cd .. and hit enter.

10. At the next prompt, type cat > hosts and hit enter.

11. Paste all the text you copied earlier from the hosts.txt file. (For example, in Putty, bring your mouse cursor to the cursor location at the bottom of the telnet window and click your right mouse button to paste.)

12. After a minute or so of the text pasting/transferring, the screen will stop scrolling. When that happens, finish the file with a Ctrl-D key combination.

13. Type dnsmasq --conf-file=/tmp/dnsmasq.conf --addn-hosts=/tmp/hosts and hit enter.

14. You are now finished. Type exit and hit enter.

15. Test out your configuration. Use a computer or connected device to use the local commands "ping" or "tracert" on known good sites (like google.com) vs. sites on the hosts list. The known good sites should have much higher ping times than the sites on the hosts list (for example, 12 ms versus less than 1 ms). The "tracert" (traceroute) comamnd should show a much lengthier Internet path to the good site than the bad site (which should only be one or two hops).

16. Again, repeat all these steps if your router goes down or is rebooted for some reason.