openssl
. For instance, to generate an RSA key, the command to use will beopenssl genpkey
.openssl
: The binary that contains the code to generate an RSA key (and manyother utilities).genpkey
: Specifies the utility to use.-algorithm RSA
: Specifies to use the RSA algorithm.-aes256
: Specifies to use the AES-256 cipher, which is newer and moresecure than DES. Default is no cipher.-out private.pem
: Specifies that a file named “private.pem” should becreated with the contents of the private key. Default is STDOUT
.private.pem
.-----BEGIN PRIVATE KEY-----
.cat private.pem
.openssl rsa
utility, which is used for processing RSA keys.cat public.pem
:-----BEGIN PUBLIC KEY-----
. If this file doesn’tstart with “BEGIN PUBLIC KEY”, do not upload it as a public key to any source!