the itjerk

my adventures with technology

Tag Archives: OpenDNS

parental controls

I have a teen that refuses to do homework. You know, gets a “zero”. Thus, I take the phone away. However, teen needs a computer for homework. Fine. But you know when she gets on to the computer, she’s going to go to all those sites where “screenagers” waste their time. That’s fine. I’m going to show you how to block individual sites using OpenDNS and your Router. [Note that I’m going to use terminology for my Netgear, but chances are if you’re bothered to read this, you’ll know what I’m talking about. Also, while my Netgear router has a “Blocked Sites” function, it doesn’t work. Useless!]

DNS can be set in many places: local computer, router, modem. I’m not quite sure what trumps what, but I believe that’s the line. Using your router for DNS is better than using your modems – my AT&T modem does not allow it to change! Setting on an device level, well, that’s a lot of work. Also, I have to believe that most “screenagers” don’t know what DNS even is. So, here we go.

The first step is to open your router’s settings and go to Internet Settings (also called WAN). Set the Primary and Secondary numbers to OpenDNS, 208.67.222.222 and 208.67.220.220. Now, all requests originating form your router will go through OpenDNS. I’m sure there is some chatter on whether using Cisco-owned product is all that good, but from what I’ve read, it’s one of the better choices out there for the home user. What you may give up in privacy, you’ll gain in secure web browsing.

The second step is to let OpenDNS know that request from your router are yours. Okay, that may sound all scary and Big Brother, but let’s not pretend that our web surfing is anonymous. It’s not. You buy your internet from someone, or are you really getting it for free from a leaky neighbor or a nearby Starbucks?

To sign up for an OpenDNS account, go to their website and sign up for a free Home account. All it requires is an email address. Once completed, open their Dashboard from a computer on your home network. Under settings, add your local network: it’s going to be the IP address of your modem. Give it name, and save it. OpenDNS will now associate requests from that IP as yours. Under Web Content Filtering, you’ll see two areas. The top is a predefined set for a variety of “undesirable” sites – if I had teenage boys, I’d sure as hell use this to block the “naughty bits”. The bottom section allows individual site blockage. Here’s what I wanted:

Give it about five-ten minutes (they say three) and those sites are as good as gone! While a web browser may give a different warning (usually a cert error), dig one deeper with nslookup, you’ll see what’s going on:

PS Desktop> nslookup snapchat.com
Server: UnKnown
Address: 192.168.0.1

Non-authoritative answer:
Name: snapchat.com
Addresses: ::ffff:146.112.61.104
146.112.61.104

And if you go to that IP:

Couple of points: First, you’ll probably need to run Cisco’s OpenDNS-Updater program as your ISP provides your modem with a dynamic host; exact same thing as if you were running a DynamicDNS service like DuckDNS. Second, a really smart kid could probably figure out how those sites are being blocked. My kid is smart, but if she was really that smart, she’d just do her homework in the first place.

One the web:
https://www.opendns.com/home-internet-security/

dnscrypt

Domain Name Service (DNS) is the mechanism by where numeric IP addresses become readable domain names; it’s far easier for me to tell you to visit strawberrybricks.com than a bunch of numbers. When you browse the internet, then, the addresses you type or click on go through a DNS search. Typically, your ISP provides this service, or whomever you get your network connection from – however there is an implicit level of trust involved. Who’s to say that yahoo.com for example, is really yahoo.com? What is the DNS server spoofed the reply? Further, any DNS server can collect a wealth of information by recording your DNS requests. Finally, the speed of your browsing is dependent on how quickly these requests are filled.

Both Google (8.8.8.8) and OpenDNS (208.67.222.222) provide free DNS services that are fast and secure, and supposedly do not track your requests. A third service, Quad9 (9.9.9.9) was very recently launched. Your ISP has a lot of information about you. Switching your DNS to one of these providers is simple (just type them in your router, or network connection), and gives some degree of privacy. Every little bit helps?

DNSCrypt goes one further by encrypting all your DNS requests. It’s an easy enough program to install, available for PC, Mac and Linux, and for routers using DD-WRT. On my Ubuntu box, I needed to install libsodium-dev first, and then was most successful installing DNSCrypt-proxy from source by using the old “configure, make, make install” method with version 1.9.5. Then, you can run it with systemd automatically.

On the web:
DNSCrypt

dns, search engines and browsing

Secure browsing is much more than clearing your browser’s cache when done surfing. While Tor Browser isn’t for everyone, two quick and easy things I recommend are using DuckDuckGo as your default search engine and switching to either GoogleDNS or OpenDNS for your web browsing. And use a modern, up to date browser!

DuckDuckGo bills itself as “the search engine that doesn’t track you”, which is reason enough to switch. The search engine results are very good, but even better, the use of bangs (!) allows searches directly to thousands of sites, including encrypted to Google (g!). Plus, it’s easy to install as the default engine on your browser.

DNS servers help resolve domain names and their numeric ip addresses. Most ISP’s DNS is notorious for being spotty, and of course, not very private. Using either Google or OpenDNS’s can speed up your browsing, protect from DNS hijacking, and offer protection from phishing. There’s a lot more to using these services than I’ll write, but just entering them into your router is the place to start.

Remember, however, that browsing security also ends with one’s exit on the web. Subject for another time…

One the web:
DuckDuckGo
Google Public DNS
OpenDNS