Use openssl as an SSL client

Extract private key and certificate from a PKCS12 file

Convert a PEM certificate into a DER format using OpenSSL

Sign a CSR with the CA‘s private key using OpenSSL

Preparation of using OpenSSL

Where to find the PKCS12 certificate imported to your machine

OpenSSL to Keytool Conversion tips

Install & Use Bouncy Castle

java.io.FilePermission

Security Debugging