Self-signed SSL Cert or CA? [closed]

Question

I would like to have the authentication and registration parts of my website encrypted (for obvious reason). This site is currently and older site which some friends and I started in middle school and still use today. I may or may not register it to be a Non-Profit Organization in the near future, but either way, a CA costs money and the organization doesn't have any and we are currently college kids.

Verisign is unreasonable and GoDaddy is $30/year. GoDaddy isn't too unreasonable, and I think their certs are accepted by most web browsers. The thing with GoDaddy is that I don't know why they have different SSL products (i.e.: why is it cheap to not verify me? does this have any implications on the cert and how the browser treats it if it just contains a domain name?)

Also, is there an issue with using my own cert? Could the login page be http, and have a line stating that I use a self-signed cert and here is it's fingerprint and then post the form to an https page? Safari's method isn't too bad or sound too scary. I'm afraid, however, that firefox 3's method will scare people away and give me a tonne of emails saying that my site is being hacked or something. I don't know how IE responds to self-signed certs. (There is also the issue of why pay for something I can create myself with no effort, but I'm not going to pose the philosophical part of it, this is a more practical question.)

In sum, do I give GoDaddy $30 a year or do I just tell people in a small paragraph what I'm doing and give the few people that will actually want my fingerprint it?

Edit: Some on a forum I was reading for more info mentioned that GoDaddy certs are only given if it's on a GoDaddy server, which this isn't. Two things: (1) is this true? and There are other CA's at about the same price, so the argument should still be the same.

Answer 1

There's a common misconception that self-signed certificates are inherently less secure than those sold by commercial CA's like GoDaddy and Verisign, and that you have to live with browser warnings/exceptions if you use them; this is incorrect.

If you securely distribute a self-signed certificate (or CA cert, as bobince suggested) and install it in the browsers that will use your site, it's just as secure as one that's purchased and is not vulnerable to man-in-the-middle attacks and cert forgery. Obviously this means that it's only feasible if only a few people need secure access to your site (e.g., internal apps, personal blogs, etc.).

In the interest of increasing awareness and encouraging fellow small-time bloggers like myself to protect themselves, I've written up a entry-level tutorial that explains the concepts behind certificates and how to safely create and use your own self-signed cert (complete with code samples and screenshots) here.

Answer 2

The SSL certificate solves two purposes: encryption of traffic (for RSA key exchange, at least) and verification of trust. As you know, you can encrypt traffic with (or without, if we're talking SSL 3.0 or TLS) any self-signed certificate. But trust is accomplished through a chain of certificates. I don't know you, but I do trust verisign (or at least Microsoft does, because they've been paid lots of money to get it installed in their operating systems by default), and since Verisign trusts you, then I trust you too. As a result, there's no scary warning when I go to such an SSL page in my Web browser because somebody that I trust has said you are who you are.

Generally, the more expensive the certificate, the more investigating that the issuing certificate authority does. So for the Extended Validation certificates, the requesters have to submit more documents to prove that they are who they say they are, and in return they get a bright, happy green bar in modern Web browsers (I think Safari doesn't do anything with it quite yet).

Finally, some companies go with the big boys like Verisign purely for the brand name alone; they know that their customers have at least heard of Verisign and so that for people shopping on their online store, their seal looks a little less sketch-ball than, say, GoDaddy's.

If the branding is not important to you or if your site is not prone to phishing attacks, then the cheapest SSL cert that you can buy that has its root installed in most Web browsers by default will be fine. Usually, the only verification done is that you must be able to reply to an e-mail sent to the DNS's administrative contact, thus "proving" that you "own" that domain name.

You can use those cheap-o certificates on non-GoDaddy servers, sure, but you'll probably have to install an intermediate certificate on the server first. This is a certificate that sits between your cheap-o $30 certificate and the GoDaddy "real deal" root certificate. Web browsers visiting your site will be like "hmm, looks like this was signed with an intermediate, you got that?" which requires may require an extra trip. But then it'll request the intermediate from your server, see that it chains up to a trusted root certificate that it knows about, and there is no problem.

But if you are not allowed to install the intermediate on your server (such as in a shared hosting scenario), then you are out of luck. This is why most people say that GoDaddy certs can't be used on non-GoDaddy servers. Not true, but true enough for many scenarios.

(At work we use a Comodo certificate for our online store, and a cheapo $30 GoDaddy cert to secure the internal connection to the database.)

Edited in italics to reflect erickson's insightful clarifications below. Learn something new every day!

Answer 3

GoDaddy is giving SSL Certificates for $15 a year via this the buy now link on this site. Don't apply coupon codes because then the price goes back to $30 a year and discounts from there.

http://www.sslshopper.com/ssl-certificate-comparison.html?ids=17,25,34,37,62