When I use
openssl genrsa -out yourdomain.key 2048 command to generate a key. I understand the yourdomain.key file contains both the private and public keys. But when I check the content of this key file, it starts and ends with
-----BEGIN PRIVATE KEY----- and
-----END PRIVATE KEY-----, which gives feeling that this file is just the private key. Why is that? This makes me very confused.
If I want to encrypt a message using private key, do I apply the entire
yourdomain.key key? Or should I extract the private key part from it and use that?