Use DNS to force youtube into restricted mode - and Pi-Hole

jonathanmmm · July 4, 2018, 6:44am

I made it with chmod +x ip.sh executable

But when I enter sudo bash ip.sh

It gives the following error:
sed: -e expression #1, char 41: unterminated `s' command

What does this mean?

jpgpi250 · July 4, 2018, 9:18am

I've never tested the script with duckduckgo, this was added later by @picante here. The script can't handle the output from dig, hence, the error message.

I've modified the script (I'm NOT a script guru, there might be a better way). Here is the summary of things you need to have, in order for this to work.

Modify /etc/hosts, it should contain:

# restricted youtube, bing, google and duckduckgo search
216.239.38.120	restrict.youtube.com
216.239.38.119	restrictmoderate.youtube.com
216.239.38.120	forcesafesearch.google.com
204.79.197.220	strict.bing.com
46.51.179.90	safe.duckduckgo.com

Create an aditional dnsmasq configuration file, for example /etc/dnsmasq.d/98-restrict.conf.
Use any number you haven't used yet, apart from 01, 02 and 03 (see earlier for an explanation). This new file should contain the following:

# YouTube
# you can also implement a moderate setting
# replace restrict.youtube.com with restrictmoderate.youtube.com
cname=www.youtube.com,restrict.youtube.com
cname=m.youtube.com,restrict.youtube.com
cname=youtubei.googleapis.com,restrict.youtube.com
cname=youtube.googleapis.com,restrict.youtube.com
cname=www.youtube-nocookie.com,restrict.youtube.com

# SafeSearch
cname=www.google.com,forcesafesearch.google.com

# Bing Family Filter
cname=www.bing.com,strict.bing.com

# duckduckgo
cname=www.duckduckgo.com,safe.duckduckgo.com

You can test the new configuration file by running:

dnsmasq --test

restart dnsmasq, if you're still using the current production version:

sudo service dnsmasq restart

if you're already using FTLDNS, restart FTLDNS (I'm not running FTLDNS, I found the restart command here):

sudo systemctl start pihole-FTL.service

You might want to update the IP addresses, using a script, but I don't think this is necessary. I wrote the original guidelines over a year ago, the addresses have not changed. Here is the updated script:

#!/bin/bash

update_ip_address() {
file=/etc/hosts
if [[ $(grep $1 $file) ]]; then
	IP=$(nslookup -query=A $1 8.8.8.8 | grep 'Address:' | tail -1 | \
		grep -oE '((1?[0-9]?[0-9]|2[0-4][0-9]|25[0-5])\.){3}((1?[0-9]?[0-9]|2[0-4][0-9]|25[0-5]))')
	sed -i "/$1/ s/.*/$IP\t$1/g" $file
fi
}

update_ip_address restrict.youtube.com
update_ip_address restrictmoderate.youtube.com
update_ip_address strict.bing.com
update_ip_address forcesafesearch.google.com
update_ip_address safe.duckduckgo.com

Hope this helps...

@DL6ER: as suggested somewhere in this topic, this might be a nice feature to add to the web interface, so users can activate / deactivate safe search with a single click.

picante · July 4, 2018, 10:29am

I didn't get duck to work. My post had a link to duck settings, which states you have to append to the URL to force safe searches, not sure if the approach discussed here can do that.

jpgpi250 · July 4, 2018, 2:43pm

According to this, using safe.duckduckgo.com is a solution, among others.

I use edge, just typed 'nude' in the address bar, this is the result:

I have no idea how to remove the possibility to turn off the option to disable the safe search. Anybody?

kevincork · July 17, 2018, 10:46am

any step by step tuto or full install script by any chance ?

jpgpi250 · July 20, 2018, 8:03am

Unfortunately, this doesn't help. pihole handles DNS entries and isn't capable of adding/modifying stuff to URL's, at least not that I know of.

The idea is to provide safe search without any local user interaction, local installation on the target machine(s), or possibility to tamper with the result.

jaykepeters · December 29, 2018, 4:56am

Hey folks, I have made a script to make this much easier!
https://raw.githubusercontent.com/jaykepeters/Scripts/Deployment/Pi-hole_SafeSearch.sh

jaykepeters · December 30, 2018, 1:39am

Thanks for the feedback, @anon55913113! I will work to implement this into the next version within an hour or so. I am not 100% sure if DuckDuckGo can be forced into SafeSearch all the time, but for now we will just add it to the CNAME's in "/etc/dnsmasq.d/05-restrict.conf" and safe.duckduckgo.com will be added to the hosts file, per your request. You are more than welcome to collaborate with me on this on GitHub as well.

jaykepeters · December 30, 2018, 1:56am

I think your idea works!
And when I try to turn safesearch off, it stays on! DuckDuckGo must have recently added this functionality as it did not work earlier this year (May/June)

jaykepeters · December 30, 2018, 4:33pm

You will never see it using forcesafesearch.google.com or safe.duckduckgo.com in the web browser, DNS does that behind the scenes. That is because it is a CNAME record. I may have mislead you, I attempted to to it in May/June but it did not work. Now it does work. This has been an open feature request with duckduckgo for some time now.

As you can see below, it is working for me:

How do the last lines of /etc/dnsmasq.d/05-restrict.conf and /etc/hosts look?

I have tried this with two pi-holes and I can confirm it is working. Is your devices' DNS cache cleared and is it using Pi-hole as it's ONLY dns server? This would cause conflict.

Try my main Public Pi-hole at 35.188.83.81, and only use 35.239.60.156 if that does not respond.... They should have Safesearch enabled...

jaykepeters · December 31, 2018, 6:29am

Thanks for checking it out! I will work on that tomorrow... So can you really eliminate the hosts entries now? How about google since there are 300+ domains...

jaykepeters · December 31, 2018, 10:04am

And where would this be added?

jaykepeters · December 31, 2018, 4:57pm

Use this: http://35.188.83.81/UniPi.php?q=ss
Do you see how google has 300+ top level domains. Each of them needs a CNAME DNS record to enforce SafeSearch. The question I was asking was: Would I just need 1 host record for Google SafeSearch forcesafesearch.google.com so I don't have to put it in the hosts file? I don't understand what your regex is for either. Is it to block other websites that may expose adult content?

jaykepeters · January 1, 2019, 4:28am

Ok, I see. You have IPV4 and IPv6 records. Could I put multiple IPV4 addresses to point to a host and dnsmasq would do it round robin? Or should I radnomly select an IP?

Happy New Year!

jaykepeters · January 1, 2019, 5:56am

I am working on making a python command line tool to acomplish this very task. This is turning into more of a project and I don't think bash will do the trick anymore. I will have it done by the end of the week.

LucasV · January 2, 2019, 2:21pm

Hi, you could do a script to go back this function? or a button to activate o deactivate? Thanks

LucasV · January 2, 2019, 2:32pm

Yes, this is a very useful and important feature

jaykepeters · January 2, 2019, 3:45pm

Sure thing! I was initially planning that, just wouldn't get to it until this week. Do you want the controls to be granular, for say enable and disable Youtube, Duckduckgo, Google SafeSearch, etc? Or do you just want all of those together in the script?

Please let me know,

Thanks,

Jayke

jaykepeters · January 2, 2019, 3:46pm

Thanks, I see. You can add multiple host-records and when you use the dig command, multiple IP addresses will be returned.

host-record=www.example.com,1.1.1.1
host-record=www.example.com,1.1.1.2
host-record=www.example.com,1.1.1.3

LucasV · January 2, 2019, 4:02pm

I think it should be a feature included from the installation and the best would be if you could choose which domains to activate this function (YouTube, Duckduckgo, Google SafeSearch, etc), thank you for your time and consideration on the subject .. but it is certainly helpful for families who have small children