Since no one has answered you yet, I hope I can at least clarify some points from the blog article you have linked to.
In the past, it was common practice for apps to maintain their own key
store if they needed to authenticate a secure SSL web server, or
authenticate the user to a server via a client certificate.
These are the two basic use-cases right here:
- If you are authenticating with a client certificate (which proves to the server that you are an authorized client), then you would only install a certificate.
- If you are trying to verify the server's identity, then you will want to validate the server's certificate. In this case you will need a keystore installed (possibly a chain if you're not using self-signed certs). The private key in the keystore will be used to validate the server's certificate.
That second bit of code you have in your question was intended for creating a certificate chain (when you're NOT using self-signed certs):
We first get the private key and certificate chain using the key alias
and then create and verify a signature to check if the key is actually
usable. Since we are using a self-signed certificate the 'chain'
consists of a single entry, but for a certificate signed by a CA you
will need to find the actual end entity certificate in the returned
array.
Installing a CA certificate is not very different from installing a
PKCS#12 file: you load the certificate in a byte array and pass it as
an extra to the install intent.
Intent intent = KeyChain.createInstallIntent();
intent.putExtra(KeyChain.EXTRA_CERTIFICATE, cert);
startActivity(intent);
I hope this explanation helps! :)
