#!/bin/bash

add_ssh_client_config () {
  local cfg=$1
  cat /etc/ssh/ssh_config | sed -n '/^Host \*/,$p' | grep -q "${cfg}"
  [ $? -eq 1 ]  && sed "/^Host \*/a\ \t${cfg}" -i /etc/ssh/ssh_config
}

# disabling SSH password login for root
sed '/^#\?PermitRootLogin/s/.*/PermitRootLogin without-password/' -i /etc/ssh/sshd_config

# enabling HostbasedAuthentication on sshd side
sed '/^#*HostbasedAuthentication/s/.*/HostbasedAuthentication yes/' -i /etc/ssh/sshd_config
sed '/^#*IgnoreUserKnownHosts/s/.*/IgnoreUserKnownHosts yes/' -i /etc/ssh/sshd_config
sed '/^#*IgnoreRhosts/s/.*/IgnoreRhosts yes/' -i /etc/ssh/sshd_config

# adding SSH agent forwarding to global client config
add_ssh_client_config "ForwardAgent yes"

# enabling HostbasedAuthentication on ssh client side
add_ssh_client_config "HostbasedAuthentication yes"
add_ssh_client_config "NoHostAuthenticationForLocalhost yes"
add_ssh_client_config "EnableSSHKeysign yes"

exit 0