container-openvpn/bin/ovpn_initpki

#!/bin/bash

#
# Initialize the EasyRSA PKI
#

if [ "$DEBUG" == "1" ]; then
  set -x
fi

set -e

source "$OPENVPN/ovpn_env.sh"

# Specify "nopass" as arg[2] to make the CA insecure (not recommended!)
nopass=$1

# Download EasyRSA because Ubuntu doesn't have it as a CLI command
wget https://github.com/OpenVPN/easy-rsa/releases/download/v3.0.4/EasyRSA-3.0.4.tgz
tar xvf EasyRSA-3.0.4.tgz

# Provides a sufficient warning before erasing pre-existing files
~/EasyRSA-3.0.4/easyrsa init-pki

# CA always has a password for protection in event server is compromised. The
# password is only needed to sign client/server certificates.  No password is
# needed for normal OpenVPN operation.
~/EasyRSA-3.0.4/easyrsa build-ca $nopass

~/EasyRSA-3.0.4/easyrsa gen-dh
openvpn --genkey --secret $EASYRSA_PKI/ta.key

# Was nice to autoset, but probably a bad idea in practice, users should
# have to explicitly specify the common name of their server
#if [ -z "$cn"]; then
#    #TODO: Handle IPv6 (when I get a VPS with IPv6)...
#    ip4=$(dig +short myip.opendns.com @resolver1.opendns.com)
#    ptr=$(dig +short -x $ip4 | sed -e 's:\.$::')
#
#    [ -n "$ptr" ] && cn=$ptr || cn=$ip4
#fi

# For a server key with a password, manually init; this is autopilot
~/EasyRSA-3.0.4/easyrsa build-server-full "$OVPN_CN" nopass

# Generate the CRL for client/server certificates revocation.
~/EasyRSA-3.0.4/easyrsa gen-crl

# Remove EasyRSA files when we're done
rm -r ~/EasyRSA-3.0.4/
rm EasyRSA-3.0.4.tgz