Using openssl utility to work with x509 certificates

Issue

OpenSSL is a cryptography toolkit implementing the Secure Sockets Layer (SSL v2/v3) and Transport Layer Security (TLS v1) network protocols and related cryptography standards required by them.

The openssl program is a command line tool for using the various cryptography functions of OpenSSL's crypto library from the shell. It can be used for various tasks, some of which will be discussed in this article, particularly concerning working with x509 certificates, certificate bundles, signing requests and keys.