Get certificate from the browser

Question

Hi friends!,
I am working with an application to get files from the client machine, to sign those files with the client's certificate and send those sign to the server.
The application get the client's certificate from a key store, but I want the applet will get the certificate from the browser.
Is that possible?.
Thanks and sorry for my little english. Greetings from Venezuela.

Answer 1

If all you're looking for is Client SSL Authentication, then you don't need to access the digital certificates through an applet; just enable ClientAuth on your web-server and let the browser handle it for you. While I haven't tried this with Chrome, Safari or Opera, I know for a fact that this works on Firefox and IE.
If you're trying to access the digital certificates/keys in the browser-keystore for digitally signing some content that the applet creates, you're going to have far more difficulty. About 10-12 years ago, Netscape provided an API that allowed you to digitally sign text-content through JavaScript. That died a quiet death, I think, since I don't know of anyone who used that capability (outside of test environments).
Years later, Mozilla added the ability to digitally sign XML content using XForms; there is even an add-on for Thunderbird (which uses the same libraries as Firefox for PKCS work): https://addons.mozilla.org/en-US/thunderbird/addon/4522/.
However, to the best of my knowledge, the only way you can get an applet to access the borwser's keystore today is to have the security policy on the client-machine modified to provide access to the local file-system, and the applet then pretty much deals with the keystore and its objects through JCE.
But, if I'm reading your post correctly, I think all you're looking for is SSL ClientAuth, for which you don't need to do anything other than enable it on your web-server that hosts the applets, and let the browser do the heavy lifting.
Arshad Noor
StrongAuth, Inc.