Native IPv6 in dd-wrt

As I mentioned in a previous post, I installed dd-wrt (kernel 2.6, VOIP, build 14896) on my wireless router (Linksys WRT320N), which connected to a VDSL modem using PPPoE. After that, it worked fine for IPv4, so I had the same functionality as the original Linksys firmware. However, the purpose of the exercise was to get IPv6 support: this turned out to be easier said than done. I was eventually able to get it working, so if you only want the short answer and aren’t interested in all the troubleshooting steps that I went through, scroll down to the Conclusion section at the bottom of this post.

Please refer to my IPv6 router post to get an overview of what I’m trying to achieve here. Most of the documentation that I’ve found assumes that you’re using a tunnel: this is similar to a proxy server, where you have an IPv4 connection to a machine on the internet, then that machine connects to your real destination using IPv6. However, I have native IPv6 connectivity from my ISP.

Continue reading “Native IPv6 in dd-wrt”

Installing dd-wrt on a Linksys WRT320N wireless router

Back in 2011 I switched ISPs to A&A, primarily because they support native IPv6. Incidentally, 3 years on I see that you still can’t get IPv6 from Zen, so I made the right choice by switching.

Windows has had IPv6 support included by default since 2006 (i.e. Vista onwards), so the missing piece of the puzzle was my wireless router (a Linksys WRT320N). Unfortunately, the built-in firmware doesn’t support IPv6. (Source: Linksys devices that support IPv6.)

So, I investigated open source alternatives. There are a few different firmware projects out there, which all seem to be based on Linux. According to the OpenWRT wiki, it isn’t supported on the WRT320N. However, the WRT320 is listed in the dd-wrt router database, so I chose that instead. JP Hellemons wrote about this in 2010 (How I upgraded my Linksys WRT320N to DD-WRT v24); he also checked Tomato and HyperWRT, and neither of those were compatible. However, apparently the NoUSB edition of Tomato USB does does support the WRT320N.

Just to forewarn anyone else who’s in a similar position, this isn’t a simple process. Here’s a good (valid) rant about how complex it is. I heard a good phrase a while ago: “Open source software is only free if your time is worthless.” I.e. if you assume that your time is valuable, consider how long it will take you to get a system working. Is it worth paying money to save yourself some time? For instance, in this case I could replace my router with a different model that has IPv6 support built in. (You will still need to invest some time in learning any system, but maybe you could reduce that from a day to an hour.)

In brief, I (eventually) got the router working fine with dd-wrt over IPv4. IPv6 took a bit longer; I’ve elaborated on that in another post (Native IPv6 in dd-wrt).

Continue reading “Installing dd-wrt on a Linksys WRT320N wireless router”

SSL: Adding a SAN to a UCC

“Hey, witch doctor, give us the magic words!”
(The Cartoons)

One of my servers has an SSL certificate from GoDaddy. More specifically, this is a Unified Communications Certificate (UCC), so it can have up to 5 domain names. I originally registered 3 names, and I recently needed to add a 4th. The good news is that GoDaddy let you specify extra names through their web interface and download the new certificate without charging any extra money. The bad news is that they don’t provide any documentation on installing the new certificate.

Continue reading “SSL: Adding a SAN to a UCC”

LUA part 3 (of 5): Compatibility problems

This post is part 3 of a series about using a limited (standard) account in Windows for everyday activities rather than logging in as a computer administrator all the time. (You may want to read part 1 and part 2 before continuing.)

If you follow my advice and switch to a limited account, you may find that some of your programs stop working. This is annoying, but there are various ways to deal with it.

Continue reading “LUA part 3 (of 5): Compatibility problems”

Open source software

Free software is a funny thing, partly because it tends to spark off “holy wars”, so it can be hard to focus on the practical issues when you’ve got people shouting about their vision of purity. I like this blog post (a parody), which applies those principles to cars: The transmission tax.

Most of the people reading this are probably aware of the basic principles, but here’s a quick recap. If you get a piece of software for your computer, it can be “closed source” or “open source”. Closed source is something like Microsoft Office or Adobe Reader: you get the application itself, so you can run it on your machine, but you don’t get the source code that the programmers used to create it. Open source means that you get the source code too, and there are some (theoretical) advantages to this:

Continue reading “Open source software”

Password security

Last year I signed up with Facebook, and the “find friends” page asked me to give them the password to my GMail account so that it could log in as me and look at my list of contacts (address book), then see whether any of those people are already registered. I, however, was disinclined to acquiesce to their request; with my password, they would be able to impersonate me (sending emails on my behalf), intercept incoming emails, and even lock me out of my own account. I’m not saying that the Facebook programmers in particular would necessarily do any of these things, but I prefer to be cautious about handing out that type of information.

This may seem a bit paranoid, but I read an interesting post today at Coding Horror: A Question of Programming Ethics. Basically, somebody wrote a shareware program called “G-Archiver” that will store a backup copy of your GMail messages on your hard drive; in order for this to work, you obviously have to provide your password. However, it turns out that the program was emailing all these passwords back to the programmer. Oops.

In fairness, you need to type your password into your computer somehow if you want to get at your email; this could be through a web browser or a dedicated email application (e.g. Outlook Express). So, you have to make the trade-off: who do you trust? Personally, I’m willing to trust Microsoft applications, although I know that other people disagree. I’m also willing to trust Firefox. However, open source isn’t a panacea; just because something can be read, that doesn’t mean that anyone has actually read it, particularly if it’s obscure. It’s also worth mentioning that the same thing could be done on other platforms (e.g. a Mac); this isn’t a virus, it’s the program doing exactly what it was designed to do.