The goal is to create a limited jail using rbash and securing it so it can only accept secure SSH sessions. It should only be used as an SSH jumphost to connect further. It should therefor not be possible to create, use or install other code in this limited environment.
All commands are executed as root inside the jail, unless specified otherwise.
Check only what the current best practices are regarding the full OpenSSH daemon configuration.
For example check; https://infosec.mozilla.org/guidelines/openssh
Make sure the daemon only listens to the assigned IP for this jail. And make sure the firewall running on the host accepts incoming and outgoing SSH connections.
```
# cat /usr/local/etc/sshd
...
ListenAddress 10.0.0.10
...
```
Stop and start the services.
```
# service sshd stop
# service openssh start
```
# User
Create a default `user` and make sure the `user` has the `/usr/local/bin/rbash` shell configured.
```
# mkdir /usr/home/user/bin
```
Symlink the only required binaries into this directory.
```
# ln -s /usr/local/bin/ssh /usr/home/user/bin/ssh
```
Create bash profile.
```
# cat /usr/home/user/.bash_profile
PATH=$HOME/bin
export PATH
```
Make sure the permissions are so that the user cannot modify its own `.(bash_)profile` files.
```
# chown root:user .bash_profile .profile
```
Remove also all unused <shell>rc files like cshrc, shrc, etc.
```
# rm .cshrc .shrc ...
```
Create `.ssh` folder and fill `authorized_keys` file (optional).
Rundeck 3.3.1 updated its 'mysql-connector-java' dependancy to version 8.0.21 which renamed the `com.mysql.jdbc.Driver` classname to `com.mysql.cj.jdbc.Driver`.