Saturday, January 2, 2010

Do it yourself CA

Recently got questions on testing with certificates. Use self-signed certificates or CA signed certs? And how to easily obtain CA signed certs? It was quite a while ago that I had been playing with certs myself. So time to refresh my mind, do some searching + experimenting, and write a blog entry about it.

CA signed certificates (SSL server and client) are recommended as only the CA cert needs to be imported as a trusted certificate (e.g. in cacerts). First option is to use a free CA like CAcert.

Second option is to setup your own (test) CA. The most obvious option is to use openssl. The command line tool of openssl allows to first create a CA keypair + CA self-signed cert and next sign certificate requests (CSR), thereby creating CA signed certificates.

Alternative tools for a do-it-yourself CA with GUI are:
Played around a bit with this SimpleAuthority, and it looks quite OK. One can import certficate signing requests and export signed cert. A very limited version is free, but to manage an unlimited number of certificates, the cost is $50 (personal) to $240 (commercial). The ease-of-use and consistency of the GUI could be improved, but it does do the job.

Notes:
  • To generate and manage keystores, thé recommended tools is Portecle.
  • Alternative is Keytool IUI: it has extra features such as signing of files, but less user friendly than Portecle.
  • All sorts of links about PKI

2 comments:

Guy Crets said...

In Security Now episode 228, reference is made to the Certificate Authority StartCom offering free (SSL) certificates, with a validity of 1 year. Startcom is a CA present in browser (e.g. in my Firefox).

jeroen said...

thanks, only knew the Keytool IUI. I'll give the other ones a go as well!