Mastering Linux Security and Hardening - Second Edition

Creating a stunnel connection on CentOS 8 – server side 

For this lab, we're using a CentOS 8 VM that's been set to run in FIPS-compliant mode (see the steps for that in Chapter 5, Encryption Technologies):

1. On a CentOS 8 VM, install stunnel:

sudo dnf install stunnel

2. On the server, within the /etc/stunnel directory, create a new stunnel.conf file with the following contents:

cert=/etc/stunnel/stunnel.pemfips=yes[hear from client]accept=30000connect=127.0.0.1:6514

3. On the server, while still within the /etc/stunnel directory, create the stunnel.pem certificate file:

sudo openssl req -new -x509 -days 3650 -nodes -out stunnel.pem -keyout stunnel.pem

4. On the server, open port 30000 on the firewall, and close port 514:

sudo firewall-cmd --permanent ...