diff --git a/Readme.md b/Readme.md
new file mode 100644
index 0000000..92f0ff1
--- /dev/null
+++ b/Readme.md
@@ -0,0 +1,3 @@
+29 0 \* /bin/bash /opt/scripts/make-backup.sh
+
+su www-data -s /bin/bash -c "php occ files:scan --path /srieger/files/Backups/Server"
\ No newline at end of file
diff --git a/backup-server-files.sh b/backup-server-files.sh
new file mode 100644
index 0000000..b99f82f
--- /dev/null
+++ b/backup-server-files.sh
@@ -0,0 +1,8 @@
+# backup
+for wort in $(ls -d */ | cut -f1 -d'/'); do echo $wort; tar -pczf ${wort}.tar.gz ${wort}; done
+
+# transfer data (SSH)
+scp -P 1022 *tar.gz simono41@65.108.123.253:
+
+# restore
+for wort in *.tar.gz; do echo $wort; tar -pxzf $wort; done
\ No newline at end of file
diff --git a/connect_adb-bridge.sh b/connect_adb-bridge.sh
new file mode 100644
index 0000000..b25852a
--- /dev/null
+++ b/connect_adb-bridge.sh
@@ -0,0 +1,2 @@
+adb pair 192.168.137.158:37983
+adb connect 192.168.137.158:42261
diff --git a/create_ssh_adb-bridge.sh b/create_ssh_adb-bridge.sh
new file mode 100644
index 0000000..582ec39
--- /dev/null
+++ b/create_ssh_adb-bridge.sh
@@ -0,0 +1,4 @@
+adb pair 192.168.137.158:37983
+adb connect 192.168.137.158:42261
+adb devices
+ssh -R 42261:spectreos.de:42261 -p1024
diff --git a/install_app_and_debug.sh b/install_app_and_debug.sh
new file mode 100644
index 0000000..47a895d
--- /dev/null
+++ b/install_app_and_debug.sh
@@ -0,0 +1 @@
+adb install app-debug.apk && adb shell am start -n de.spectreos.battlestar/de.spectreos.battlestar.MainActivity && sleep 2 && adb logcat --pid=$(adb shell pidof -s de.spectreos.battlestar)
diff --git a/make-backup.sh b/make-backup.sh
new file mode 100644
index 0000000..5cffd5e
--- /dev/null
+++ b/make-backup.sh
@@ -0,0 +1,13 @@
+#!/bin/bash
+
+BACKUPTIME=`date +%b-%d-%y` #get the current date
+
+DESTINATION=/var/www/html/data/sebastian/files/backups/backup-documents-$BACKUPTIME.tar.gz #create a backup file using the current date in it's name
+
+SOURCEFOLDER=/var/www/html/data/sebastian/files/Documents #the folder that contains the files that we want to backup
+
+tar -cpzf $DESTINATION $SOURCEFOLDER #create the backup
+
+su www-data -s /bin/bash -c "php occ files:scan --path /sebastian/"
+
+chown -cRv www-data:www-data data/sebastian/files/backups
diff --git a/ocr.sh b/ocr.sh
new file mode 100644
index 0000000..bae5933
--- /dev/null
+++ b/ocr.sh
@@ -0,0 +1 @@
+ocrmypdf -l deu --force-ocr $1 $1
diff --git a/openvpn-install.sh b/openvpn-install.sh
index bc1f292..b813c54 100755
--- a/openvpn-install.sh
+++ b/openvpn-install.sh
@@ -1,492 +1,766 @@
-#!/usr/bin/env bash
+#!/bin/bash
+# shellcheck disable=SC1091,SC2164,SC2034,SC1072,SC1073,SC1009
 
-# Secure OpenVPN server installer for Debian, Ubuntu, CentOS and Arch Linux
-# https://github.com/Angristan/OpenVPN-install
+# Secure OpenVPN server installer for Debian, Ubuntu, CentOS, Amazon Linux 2, Fedora and Arch Linux
+# https://github.com/angristan/openvpn-install
 
-set -ex
-
-if [[ "$EUID" -ne 0 ]]; then
-    echo "Sorry, you need to run this as root"
-    sudo $0
-    exit 0
-fi
-
-if [[ ! -e /dev/net/tun ]]; then
-    echo "TUN is not available"
-    exit 2
-fi
-
-if grep -qs "CentOS release 5" "/etc/redhat-release"; then
-    echo "CentOS 5 is too old and not supported"
-    exit 3
-fi
-
-if [[ -e /etc/debian_version ]]; then
-    OS="debian"
-    # Getting the version number, to verify that a recent version of OpenVPN is available
-    VERSION_ID=$(cat /etc/os-release | grep "VERSION_ID")
-    IPTABLES='/etc/iptables/iptables.rules'
-    SYSCTL='/etc/sysctl.conf'
-    if [[ "$VERSION_ID" != 'VERSION_ID="7"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="8"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="9"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="12.04"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="14.04"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="16.04"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="16.10"' ]] && [[ "$VERSION_ID" != 'VERSION_ID="17.04"' ]]; then
-        echo "Your version of Debian/Ubuntu is not supported."
-        echo "I can't install a recent version of OpenVPN on your system."
-        echo ""
-        echo "However, if you're using Debian unstable/testing, or Ubuntu beta,"
-        echo "then you can continue, a recent version of OpenVPN is available on these."
-        echo "Keep in mind they are not supported, though."
-        while [[ $CONTINUE != "y" && $CONTINUE != "n" ]]; do
-            read -p "Continue ? [y/n]: " -e CONTINUE
-        done
-        if [[ "$CONTINUE" = "n" ]]; then
-            echo "Ok, bye !"
-            exit 4
-        fi
-    fi
-elif [[ -e /etc/centos-release || -e /etc/redhat-release ]]; then
-    OS=centos
-    IPTABLES='/etc/iptables/iptables.rules'
-    SYSCTL='/etc/sysctl.conf'
-elif [[ -e /etc/arch-release ]]; then
-    OS=arch
-    IPTABLES='/etc/iptables/iptables.rules'
-    SYSCTL='/etc/sysctl.d/openvpn.conf'
-else
-    echo "Looks like you aren't running this installer on a Debian, Ubuntu, CentOS or ArchLinux system"
-    exit 4
-fi
-
-newclient () {
-    # Where to write the custom client.ovpn?
-    if [ -e /home/$1 ]; then  # if $1 is a user name
-        homeDir="/home/$1"
-    elif [ ${SUDO_USER} ]; then   # if not, use SUDO_USER
-        homeDir="/home/${SUDO_USER}"
-    else  # if not SUDO_USER, use /root
-        homeDir="/root"
-    fi
-    # Generates the custom client.ovpn
-    cp /etc/openvpn/client-template.txt $homeDir/$1.ovpn
-    echo "<ca>" >> $homeDir/$1.ovpn
-    cat /etc/openvpn/easy-rsa/pki/ca.crt >> $homeDir/$1.ovpn
-    echo "</ca>" >> $homeDir/$1.ovpn
-    echo "<cert>" >> $homeDir/$1.ovpn
-    cat /etc/openvpn/easy-rsa/pki/issued/$1.crt >> $homeDir/$1.ovpn
-    echo "</cert>" >> $homeDir/$1.ovpn
-    echo "<key>" >> $homeDir/$1.ovpn
-    cat /etc/openvpn/easy-rsa/pki/private/$1.key >> $homeDir/$1.ovpn
-    echo "</key>" >> $homeDir/$1.ovpn
-    echo "key-direction 1" >> $homeDir/$1.ovpn
-    echo "<tls-auth>" >> $homeDir/$1.ovpn
-    cat /etc/openvpn/tls-auth.key >> $homeDir/$1.ovpn
-    echo "</tls-auth>" >> $homeDir/$1.ovpn
+function isRoot() {
+	if [ "$EUID" -ne 0 ]; then
+		return 1
+	fi
 }
 
-# Try to get our IP from the system and fallback to the Internet.
-# I do this to make the script compatible with NATed servers (LowEndSpirit/Scaleway)
-# and to avoid getting an IPv6.
-IP=$(ip addr | grep 'inet' | grep -v inet6 | grep -vE '127\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' | grep -o -E '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' | head -1)
-if [[ "$IP" = "" ]]; then
-    IP=$(wget -qO- ipv4.icanhazip.com)
-fi
-# Get Internet network interface with default route
-NIC=$(ip -4 route ls | grep default | grep -Po '(?<=dev )(\S+)' | head -1)
+function tunAvailable() {
+	if [ ! -e /dev/net/tun ]; then
+		return 1
+	fi
+}
 
-if [[ -e /etc/openvpn/server.conf ]]; then
-    while :
-    do
-        clear
-        echo "OpenVPN-install (github.com/Angristan/OpenVPN-install)"
-        echo ""
-        echo "Looks like OpenVPN is already installed"
-        echo ""
-        echo "What do you want to do?"
-        echo "   1) Add a cert for a new user"
-        echo "   2) Revoke existing user cert"
-        echo "   3) Remove OpenVPN"
-        echo "   4) Exit"
-        read -p "Select an option [1-4]: " option
-        case $option in
-            1)
-                echo ""
-                echo "Tell me a name for the client cert"
-                echo "Please, use one word only, no special characters"
-                read -p "Client name: " -e -i client CLIENT
-                cd /etc/openvpn/easy-rsa/
-                ./easyrsa build-client-full $CLIENT nopass
-                # Generates the custom client.ovpn
-                newclient "$CLIENT"
-                echo ""
-                echo "Client $CLIENT added, certs available at $homeDir/$CLIENT.ovpn"
-                exit
-                ;;
-            2)
-                NUMBEROFCLIENTS=$(tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep -c "^V")
-                if [[ "$NUMBEROFCLIENTS" = '0' ]]; then
-                    echo ""
-                    echo "You have no existing clients!"
-                    exit 5
-                fi
-                echo ""
-                echo "Select the existing client certificate you want to revoke"
-                tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep "^V" | cut -d '=' -f 2 | nl -s ') '
-                if [[ "$NUMBEROFCLIENTS" = '1' ]]; then
-                    read -p "Select one client [1]: " CLIENTNUMBER
-                else
-                    read -p "Select one client [1-$NUMBEROFCLIENTS]: " CLIENTNUMBER
-                fi
-                CLIENT=$(tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep "^V" | cut -d '=' -f 2 | sed -n "$CLIENTNUMBER"p)
-                cd /etc/openvpn/easy-rsa/
-                ./easyrsa --batch revoke $CLIENT
-                EASYRSA_CRL_DAYS=3650 ./easyrsa gen-crl
-                rm -rf pki/reqs/$CLIENT.req
-                rm -rf pki/private/$CLIENT.key
-                rm -rf pki/issued/$CLIENT.crt
-                rm -rf /etc/openvpn/crl.pem
-                cp /etc/openvpn/easy-rsa/pki/crl.pem /etc/openvpn/crl.pem
-                chmod 644 /etc/openvpn/crl.pem
-                echo ""
-                echo "Certificate for client $CLIENT revoked"
-                echo "Exiting..."
-                exit
-                ;;
-            3)
-                echo ""
-                read -p "Do you really want to remove OpenVPN? [y/n]: " -e -i n REMOVE
-                if [[ "$REMOVE" = 'y' ]]; then
-                    PORT=$(grep '^port ' /etc/openvpn/server.conf | cut -d " " -f 2)
-                    if pgrep firewalld; then
-                        # Using both permanent and not permanent rules to avoid a firewalld reload.
-                        firewall-cmd --zone=public --remove-port=$PORT/udp
-                        firewall-cmd --zone=trusted --remove-source=10.8.0.0/24
-                        firewall-cmd --permanent --zone=public --remove-port=$PORT/udp
-                        firewall-cmd --permanent --zone=trusted --remove-source=10.8.0.0/24
-                    fi
-                    if iptables -L -n | grep -qE 'REJECT|DROP'; then
-                        if [[ "$PROTOCOL" = 'udp' ]]; then
-                            iptables -D INPUT -p udp --dport $PORT -j ACCEPT
-                        else
-                            iptables -D INPUT -p tcp --dport $PORT -j ACCEPT
-                        fi
-                        iptables -D FORWARD -s 10.8.0.0/24 -j ACCEPT
-                        iptables-save > $IPTABLES
-                    fi
-                    iptables -t nat -D POSTROUTING -o $NIC -s 10.8.0.0/24 -j MASQUERADE
-                    iptables-save > $IPTABLES
-                    if hash sestatus 2>/dev/null; then
-                        if sestatus | grep "Current mode" | grep -qs "enforcing"; then
-                            if [[ "$PORT" != '1194' ]]; then
-                                semanage port -d -t openvpn_port_t -p udp $PORT
-                            fi
-                        fi
-                    fi
-                    if [[ "$OS" = 'debian' ]]; then
-                        apt-get autoremove --purge -y openvpn
-                    elif [[ "$OS" = 'arch' ]]; then
-                        pacman -R openvpn --noconfirm
-                    else
-                        yum remove openvpn -y
-                    fi
-                    rm -rf /etc/openvpn
-                    rm -rf /usr/share/doc/openvpn*
-                    echo ""
-                    echo "OpenVPN removed!"
-                else
-                    echo ""
-                    echo "Removal aborted!"
-                fi
-                exit
-                ;;
-            4) exit ;;
-        esac
-    done
-else
-    clear
-    echo "Welcome to the secure OpenVPN installer (github.com/Angristan/OpenVPN-install)"
-    echo ""
-    # OpenVPN setup and first user creation
-    echo "I need to ask you a few questions before starting the setup"
-    echo "You can leave the default options and just press enter if you are ok with them"
-    echo ""
-    echo "I need to know the IPv4 address of the network interface you want OpenVPN listening to."
-    echo "If your server is running behind a NAT, (e.g. LowEndSpirit, Scaleway) leave the IP address as it is. (local/private IP)"
-    echo "Otherwise, it should be your public IPv4 address."
-    read -p "IP address: " -e -i $IP IP
-    echo ""
-    echo "What port do you want for OpenVPN?"
-    read -p "Port: " -e -i 1194 PORT
-    echo ""
-    echo "What protocol do you want for OpenVPN?"
-    echo "Unless UDP is blocked, you should not use TCP (unnecessarily slower)"
-    while [[ $PROTOCOL != "UDP" && $PROTOCOL != "TCP" ]]; do
-        read -p "Protocol [UDP/TCP]: " -e -i UDP PROTOCOL
-    done
-    echo ""
-    echo "What DNS do you want to use with the VPN?"
-    echo "   1) Current system resolvers (from /etc/resolv.conf)"
-    echo "   2) Quad9 (Anycast: worldwide)"
-    echo "   3) FDN (France)"
-    echo "   4) DNS.WATCH (Germany)"
-    echo "   5) OpenDNS (Anycast: worldwide)"
-    echo "   6) Google (Anycast: worldwide)"
-    echo "   7) Yandex Basic (Russia)"
-    echo "   8) AdGuard DNS (Russia)"
-    while [[ $DNS != "1" && $DNS != "2" && $DNS != "3" && $DNS != "4" && $DNS != "5" && $DNS != "6" && $DNS != "7" && $DNS != "8" ]]; do
-        read -p "DNS [1-8]: " -e -i 1 DNS
-    done
-    echo ""
-    echo "See https://github.com/Angristan/OpenVPN-install#encryption to learn more about "
-    echo "the encryption in OpenVPN and the choices I made in this script."
-    echo "Please note that all the choices proposed are secure (to a different degree)"
-    echo "and are still viable to date, unlike some default OpenVPN options"
-    echo ''
-    echo "Choose which cipher you want to use for the data channel:"
-    echo "   1) AES-128-CBC (fastest and sufficiently secure for everyone, recommended)"
-    echo "   2) AES-192-CBC"
-    echo "   3) AES-256-CBC"
-    echo "Alternatives to AES, use them only if you know what you're doing."
-    echo "They are relatively slower but as secure as AES."
-    echo "   4) CAMELLIA-128-CBC"
-    echo "   5) CAMELLIA-192-CBC"
-    echo "   6) CAMELLIA-256-CBC"
-    echo "   7) SEED-CBC"
-    while [[ $CIPHER != "1" && $CIPHER != "2" && $CIPHER != "3" && $CIPHER != "4" && $CIPHER != "5" && $CIPHER != "6" && $CIPHER != "7" ]]; do
-        read -p "Cipher [1-7]: " -e -i 1 CIPHER
-    done
-    case $CIPHER in
-        1)
-            CIPHER="cipher AES-128-CBC"
-            ;;
-        2)
-            CIPHER="cipher AES-192-CBC"
-            ;;
-        3)
-            CIPHER="cipher AES-256-CBC"
-            ;;
-        4)
-            CIPHER="cipher CAMELLIA-128-CBC"
-            ;;
-        5)
-            CIPHER="cipher CAMELLIA-192-CBC"
-            ;;
-        6)
-            CIPHER="cipher CAMELLIA-256-CBC"
-            ;;
-        7)
-            CIPHER="cipher SEED-CBC"
-            ;;
-    esac
-    echo ""
-    echo "Choose what size of Diffie-Hellman key you want to use:"
-    echo "   1) 2048 bits (fastest)"
-    echo "   2) 3072 bits (recommended, best compromise)"
-    echo "   3) 4096 bits (most secure)"
-    while [[ $DH_KEY_SIZE != "1" && $DH_KEY_SIZE != "2" && $DH_KEY_SIZE != "3" ]]; do
-        read -p "DH key size [1-3]: " -e -i 2 DH_KEY_SIZE
-    done
-    case $DH_KEY_SIZE in
-        1)
-            DH_KEY_SIZE="2048"
-            ;;
-        2)
-            DH_KEY_SIZE="3072"
-            ;;
-        3)
-            DH_KEY_SIZE="4096"
-            ;;
-    esac
-    echo ""
-    echo "Choose what size of RSA key you want to use:"
-    echo "   1) 2048 bits (fastest)"
-    echo "   2) 3072 bits (recommended, best compromise)"
-    echo "   3) 4096 bits (most secure)"
-    while [[ $RSA_KEY_SIZE != "1" && $RSA_KEY_SIZE != "2" && $RSA_KEY_SIZE != "3" ]]; do
-        read -p "RSA key size [1-3]: " -e -i 2 RSA_KEY_SIZE
-    done
-    case $RSA_KEY_SIZE in
-        1)
-            RSA_KEY_SIZE="2048"
-            ;;
-        2)
-            RSA_KEY_SIZE="3072"
-            ;;
-        3)
-            RSA_KEY_SIZE="4096"
-            ;;
-    esac
-    echo ""
-    echo "Finally, tell me a name for the client certificate and configuration"
-    while [[ $CLIENT = "" ]]; do
-        echo "Please, use one word only, no special characters"
-        read -p "Client name: " -e -i client CLIENT
-    done
-    echo ""
-    echo "Okay, that was all I needed. We are ready to setup your OpenVPN server now"
-    read -n1 -r -p "Press any key to continue..."
+function checkOS() {
+	if [[ -e /etc/debian_version ]]; then
+		OS="debian"
+		source /etc/os-release
 
-    if [[ "$OS" = 'debian' ]]; then
-        apt-get install ca-certificates -y
-        # We add the OpenVPN repo to get the latest version.
-        # Debian 7
-        if [[ "$VERSION_ID" = 'VERSION_ID="7"' ]]; then
-            echo "deb http://build.openvpn.net/debian/openvpn/stable wheezy main" > /etc/apt/sources.list.d/openvpn.list
-            wget -O - https://swupdate.openvpn.net/repos/repo-public.gpg | apt-key add -
-            apt-get update
-        fi
-        # Debian 8
-        if [[ "$VERSION_ID" = 'VERSION_ID="8"' ]]; then
-            echo "deb http://build.openvpn.net/debian/openvpn/stable jessie main" > /etc/apt/sources.list.d/openvpn.list
-            wget -O - https://swupdate.openvpn.net/repos/repo-public.gpg | apt-key add -
-            apt update
-        fi
-        # Ubuntu 12.04
-        if [[ "$VERSION_ID" = 'VERSION_ID="12.04"' ]]; then
-            echo "deb http://build.openvpn.net/debian/openvpn/stable precise main" > /etc/apt/sources.list.d/openvpn.list
-            wget -O - https://swupdate.openvpn.net/repos/repo-public.gpg | apt-key add -
-            apt-get update
-        fi
-        # Ubuntu 14.04
-        if [[ "$VERSION_ID" = 'VERSION_ID="14.04"' ]]; then
-            echo "deb http://build.openvpn.net/debian/openvpn/stable trusty main" > /etc/apt/sources.list.d/openvpn.list
-            wget -O - https://swupdate.openvpn.net/repos/repo-public.gpg | apt-key add -
-            apt-get update
-        fi
-        # Ubuntu >= 16.04 and Debian > 8 have OpenVPN > 2.3.3 without the need of a third party repository.
-        # The we install OpenVPN
-        apt-get install openvpn iptables openssl wget ca-certificates curl -y
-        # Install iptables service
-        if [[ ! -e /etc/systemd/system/iptables.service ]]; then
-            mkdir /etc/iptables
-            iptables-save > /etc/iptables/iptables.rules
-            echo "#!/bin/sh
-iptables -F
-iptables -X
-iptables -t nat -F
-iptables -t nat -X
-iptables -t mangle -F
-iptables -t mangle -X
-iptables -P INPUT ACCEPT
-iptables -P FORWARD ACCEPT
-            iptables -P OUTPUT ACCEPT" > /etc/iptables/flush-iptables.sh
-            chmod +x /etc/iptables/flush-iptables.sh
-            echo "[Unit]
-Description=Packet Filtering Framework
-DefaultDependencies=no
-Before=network-pre.target
-Wants=network-pre.target
-[Service]
-Type=oneshot
-ExecStart=/sbin/iptables-restore /etc/iptables/iptables.rules
-ExecReload=/sbin/iptables-restore /etc/iptables/iptables.rules
-ExecStop=/etc/iptables/flush-iptables.sh
-RemainAfterExit=yes
-[Install]
-            WantedBy=multi-user.target" > /etc/systemd/system/iptables.service
-            systemctl daemon-reload
-            systemctl enable iptables.service
-        fi
-    elif [[ "$OS" = 'centos' ]]; then
-        yum install epel-release -y
-        yum install openvpn iptables openssl wget ca-certificates curl -y
-        # Install iptables service
-        if [[ ! -e /etc/systemd/system/iptables.service ]]; then
-            mkdir /etc/iptables
-            iptables-save > /etc/iptables/iptables.rules
-            echo "#!/bin/sh
-iptables -F
-iptables -X
-iptables -t nat -F
-iptables -t nat -X
-iptables -t mangle -F
-iptables -t mangle -X
-iptables -P INPUT ACCEPT
-iptables -P FORWARD ACCEPT
-            iptables -P OUTPUT ACCEPT" > /etc/iptables/flush-iptables.sh
-            chmod +x /etc/iptables/flush-iptables.sh
-            echo "[Unit]
-Description=Packet Filtering Framework
-DefaultDependencies=no
-Before=network-pre.target
-Wants=network-pre.target
-[Service]
-Type=oneshot
-ExecStart=/sbin/iptables-restore /etc/iptables/iptables.rules
-ExecReload=/sbin/iptables-restore /etc/iptables/iptables.rules
-ExecStop=/etc/iptables/flush-iptables.sh
-RemainAfterExit=yes
-[Install]
-            WantedBy=multi-user.target" > /etc/systemd/system/iptables.service
-            systemctl daemon-reload
-            systemctl enable iptables.service
-            # Disable firewalld to allow iptables to start upon reboot
-            systemctl disable firewalld
-        fi
-    else
-        # Else, the distro is ArchLinux
-        echo ""
-        echo ""
-        echo "As you're using ArchLinux, I need to update the packages on your system to install those I need."
-        echo "Not doing that could cause problems between dependencies, or missing files in repositories."
-        echo ""
-        echo "Continuing will update your installed packages and install needed ones."
-        while [[ $CONTINUE != "y" && $CONTINUE != "n" ]]; do
-            read -p "Continue ? [y/n]: " -e -i y CONTINUE
-        done
-        if [[ "$CONTINUE" = "n" ]]; then
-            echo "Ok, bye !"
-            exit 4
-        fi
+		if [[ $ID == "debian" || $ID == "raspbian" ]]; then
+			if [[ $VERSION_ID -lt 9 ]]; then
+				echo "⚠️ Your version of Debian is not supported."
+				echo ""
+				echo "However, if you're using Debian >= 9 or unstable/testing then you can continue, at your own risk."
+				echo ""
+				until [[ $CONTINUE =~ (y|n) ]]; do
+					read -rp "Continue? [y/n]: " -e CONTINUE
+				done
+				if [[ $CONTINUE == "n" ]]; then
+					exit 1
+				fi
+			fi
+		elif [[ $ID == "ubuntu" ]]; then
+			OS="ubuntu"
+			MAJOR_UBUNTU_VERSION=$(echo "$VERSION_ID" | cut -d '.' -f1)
+			if [[ $MAJOR_UBUNTU_VERSION -lt 16 ]]; then
+				echo "⚠️ Your version of Ubuntu is not supported."
+				echo ""
+				echo "However, if you're using Ubuntu >= 16.04 or beta, then you can continue, at your own risk."
+				echo ""
+				until [[ $CONTINUE =~ (y|n) ]]; do
+					read -rp "Continue? [y/n]: " -e CONTINUE
+				done
+				if [[ $CONTINUE == "n" ]]; then
+					exit 1
+				fi
+			fi
+		fi
+	elif [[ -e /etc/system-release ]]; then
+		source /etc/os-release
+		if [[ $ID == "fedora" ]]; then
+			OS="fedora"
+		fi
+		if [[ $ID == "centos" ]]; then
+			OS="centos"
+			if [[ ! $VERSION_ID =~ (7|8) ]]; then
+				echo "⚠️ Your version of CentOS is not supported."
+				echo ""
+				echo "The script only support CentOS 7 and CentOS 8."
+				echo ""
+				exit 1
+			fi
+		fi
+		if [[ $ID == "amzn" ]]; then
+			OS="amzn"
+			if [[ $VERSION_ID != "2" ]]; then
+				echo "⚠️ Your version of Amazon Linux is not supported."
+				echo ""
+				echo "The script only support Amazon Linux 2."
+				echo ""
+				exit 1
+			fi
+		fi
+	elif [[ -e /etc/arch-release ]]; then
+		OS=arch
+	else
+		echo "Looks like you aren't running this installer on a Debian, Ubuntu, Fedora, CentOS, Amazon Linux 2 or Arch Linux system"
+		exit 1
+	fi
+}
 
-        if [[ "$OS" = 'arch' ]]; then
-            # Install dependencies
-            pacman -Syu openvpn iptables openssl wget ca-certificates curl --needed --noconfirm
-            iptables-save > /etc/iptables/iptables.rules # iptables won't start if this file does not exist
-            systemctl daemon-reload
-            systemctl enable iptables
-            systemctl start iptables
-        fi
-    fi
-    # Find out if the machine uses nogroup or nobody for the permissionless group
-    if grep -qs "^nogroup:" /etc/group; then
-        NOGROUP=nogroup
-    else
-        NOGROUP=nobody
-    fi
+function initialCheck() {
+	if ! isRoot; then
+		echo "Sorry, you need to run this as root"
+		exit 1
+	fi
+	if ! tunAvailable; then
+		echo "TUN is not available"
+		exit 1
+	fi
+	checkOS
+}
 
-    # An old version of easy-rsa was available by default in some openvpn packages
-    if [[ -d /etc/openvpn/easy-rsa/ ]]; then
-        rm -rf /etc/openvpn/easy-rsa/
-    fi
-    # Get easy-rsa
-    wget -O ~/EasyRSA-3.0.3.tgz https://github.com/OpenVPN/easy-rsa/releases/download/v3.0.3/EasyRSA-3.0.3.tgz
-    tar xzf ~/EasyRSA-3.0.3.tgz -C ~/
-    mv ~/EasyRSA-3.0.3/ /etc/openvpn/
-    mv /etc/openvpn/EasyRSA-3.0.3/ /etc/openvpn/easy-rsa/
-    chown -R root:root /etc/openvpn/easy-rsa/
-    rm -rf ~/EasyRSA-3.0.3.tgz
-    cd /etc/openvpn/easy-rsa/
-    echo "set_var EASYRSA_KEY_SIZE $RSA_KEY_SIZE" > vars
-    # Create the PKI, set up the CA, the DH params and the server + client certificates
-    ./easyrsa init-pki
-    ./easyrsa --batch build-ca nopass
-    openssl dhparam -out dh.pem $DH_KEY_SIZE
-    ./easyrsa build-server-full server nopass
-    ./easyrsa build-client-full $CLIENT nopass
-    EASYRSA_CRL_DAYS=3650 ./easyrsa gen-crl
-    # generate tls-auth key
-    openvpn --genkey --secret /etc/openvpn/tls-auth.key
-    # Move all the generated files
-    cp pki/ca.crt pki/private/ca.key dh.pem pki/issued/server.crt pki/private/server.key /etc/openvpn/easy-rsa/pki/crl.pem /etc/openvpn
-    # Make cert revocation list readable for non-root
-    chmod 644 /etc/openvpn/crl.pem
+function installUnbound() {
+	# If Unbound isn't installed, install it
+	if [[ ! -e /etc/unbound/unbound.conf ]]; then
 
-    # Generate server.conf
-    echo "port $PORT" > /etc/openvpn/server.conf
-    if [[ "$PROTOCOL" = 'UDP' ]]; then
-        echo "proto udp" >> /etc/openvpn/server.conf
-    elif [[ "$PROTOCOL" = 'TCP' ]]; then
-        echo "proto tcp" >> /etc/openvpn/server.conf
-    fi
-    echo "dev tun
+		if [[ $OS =~ (debian|ubuntu) ]]; then
+			apt-get install -y unbound
+
+			# Configuration
+			echo 'interface: 10.8.0.1
+access-control: 10.8.0.1/24 allow
+hide-identity: yes
+hide-version: yes
+use-caps-for-id: yes
+prefetch: yes' >>/etc/unbound/unbound.conf
+
+		elif [[ $OS =~ (centos|amzn) ]]; then
+			yum install -y unbound
+
+			# Configuration
+			sed -i 's|# interface: 0.0.0.0$|interface: 10.8.0.1|' /etc/unbound/unbound.conf
+			sed -i 's|# access-control: 127.0.0.0/8 allow|access-control: 10.8.0.1/24 allow|' /etc/unbound/unbound.conf
+			sed -i 's|# hide-identity: no|hide-identity: yes|' /etc/unbound/unbound.conf
+			sed -i 's|# hide-version: no|hide-version: yes|' /etc/unbound/unbound.conf
+			sed -i 's|use-caps-for-id: no|use-caps-for-id: yes|' /etc/unbound/unbound.conf
+
+		elif [[ $OS == "fedora" ]]; then
+			dnf install -y unbound
+
+			# Configuration
+			sed -i 's|# interface: 0.0.0.0$|interface: 10.8.0.1|' /etc/unbound/unbound.conf
+			sed -i 's|# access-control: 127.0.0.0/8 allow|access-control: 10.8.0.1/24 allow|' /etc/unbound/unbound.conf
+			sed -i 's|# hide-identity: no|hide-identity: yes|' /etc/unbound/unbound.conf
+			sed -i 's|# hide-version: no|hide-version: yes|' /etc/unbound/unbound.conf
+			sed -i 's|# use-caps-for-id: no|use-caps-for-id: yes|' /etc/unbound/unbound.conf
+
+		elif [[ $OS == "arch" ]]; then
+			pacman -Syu --noconfirm unbound
+
+			# Get root servers list
+			curl -o /etc/unbound/root.hints https://www.internic.net/domain/named.cache
+
+			if [[ ! -f /etc/unbound/unbound.conf.old ]]; then
+				mv /etc/unbound/unbound.conf /etc/unbound/unbound.conf.old
+			fi
+
+			echo 'server:
+	use-syslog: yes
+	do-daemonize: no
+	username: "unbound"
+	directory: "/etc/unbound"
+	trust-anchor-file: trusted-key.key
+	root-hints: root.hints
+	interface: 10.8.0.1
+	access-control: 10.8.0.1/24 allow
+	port: 53
+	num-threads: 2
+	use-caps-for-id: yes
+	harden-glue: yes
+	hide-identity: yes
+	hide-version: yes
+	qname-minimisation: yes
+	prefetch: yes' >/etc/unbound/unbound.conf
+		fi
+
+		# IPv6 DNS for all OS
+		if [[ $IPV6_SUPPORT == 'y' ]]; then
+			echo 'interface: fd42:42:42:42::1
+access-control: fd42:42:42:42::/112 allow' >>/etc/unbound/unbound.conf
+		fi
+
+		if [[ ! $OS =~ (fedora|centos|amzn) ]]; then
+			# DNS Rebinding fix
+			echo "private-address: 10.0.0.0/8
+private-address: fd42:42:42:42::/112
+private-address: 172.16.0.0/12
+private-address: 192.168.0.0/16
+private-address: 169.254.0.0/16
+private-address: fd00::/8
+private-address: fe80::/10
+private-address: 127.0.0.0/8
+private-address: ::ffff:0:0/96" >>/etc/unbound/unbound.conf
+		fi
+	else # Unbound is already installed
+		echo 'include: /etc/unbound/openvpn.conf' >>/etc/unbound/unbound.conf
+
+		# Add Unbound 'server' for the OpenVPN subnet
+		echo 'server:
+interface: 10.8.0.1
+access-control: 10.8.0.1/24 allow
+hide-identity: yes
+hide-version: yes
+use-caps-for-id: yes
+prefetch: yes
+private-address: 10.0.0.0/8
+private-address: fd42:42:42:42::/112
+private-address: 172.16.0.0/12
+private-address: 192.168.0.0/16
+private-address: 169.254.0.0/16
+private-address: fd00::/8
+private-address: fe80::/10
+private-address: 127.0.0.0/8
+private-address: ::ffff:0:0/96' >/etc/unbound/openvpn.conf
+		if [[ $IPV6_SUPPORT == 'y' ]]; then
+			echo 'interface: fd42:42:42:42::1
+access-control: fd42:42:42:42::/112 allow' >>/etc/unbound/openvpn.conf
+		fi
+	fi
+
+	systemctl enable unbound
+	systemctl restart unbound
+}
+
+function installQuestions() {
+	echo "Welcome to the OpenVPN installer!"
+	echo "The git repository is available at: https://github.com/angristan/openvpn-install"
+	echo ""
+
+	echo "I need to ask you a few questions before starting the setup."
+	echo "You can leave the default options and just press enter if you are ok with them."
+	echo ""
+	echo "I need to know the IPv4 address of the network interface you want OpenVPN listening to."
+	echo "Unless your server is behind NAT, it should be your public IPv4 address."
+
+	# Detect public IPv4 address and pre-fill for the user
+	IP=$(ip -4 addr | sed -ne 's|^.* inet \([^/]*\)/.* scope global.*$|\1|p' | head -1)
+
+	if [[ -z $IP ]]; then
+		# Detect public IPv6 address
+		IP=$(ip -6 addr | sed -ne 's|^.* inet6 \([^/]*\)/.* scope global.*$|\1|p' | head -1)
+	fi
+	APPROVE_IP=${APPROVE_IP:-n}
+	if [[ $APPROVE_IP =~ n ]]; then
+		read -rp "IP address: " -e -i "$IP" IP
+	fi
+	# If $IP is a private IP address, the server must be behind NAT
+	if echo "$IP" | grep -qE '^(10\.|172\.1[6789]\.|172\.2[0-9]\.|172\.3[01]\.|192\.168)'; then
+		echo ""
+		echo "It seems this server is behind NAT. What is its public IPv4 address or hostname?"
+		echo "We need it for the clients to connect to the server."
+
+		PUBLICIP=$(curl -s https://api.ipify.org)
+		until [[ $ENDPOINT != "" ]]; do
+			read -rp "Public IPv4 address or hostname: " -e -i "$PUBLICIP" ENDPOINT
+		done
+	fi
+
+	echo ""
+	echo "Checking for IPv6 connectivity..."
+	echo ""
+	# "ping6" and "ping -6" availability varies depending on the distribution
+	if type ping6 >/dev/null 2>&1; then
+		PING6="ping6 -c3 ipv6.google.com > /dev/null 2>&1"
+	else
+		PING6="ping -6 -c3 ipv6.google.com > /dev/null 2>&1"
+	fi
+	if eval "$PING6"; then
+		echo "Your host appears to have IPv6 connectivity."
+		SUGGESTION="y"
+	else
+		echo "Your host does not appear to have IPv6 connectivity."
+		SUGGESTION="n"
+	fi
+	echo ""
+	# Ask the user if they want to enable IPv6 regardless its availability.
+	until [[ $IPV6_SUPPORT =~ (y|n) ]]; do
+		read -rp "Do you want to enable IPv6 support (NAT)? [y/n]: " -e -i $SUGGESTION IPV6_SUPPORT
+	done
+	echo ""
+	echo "What port do you want OpenVPN to listen to?"
+	echo "   1) Default: 1194"
+	echo "   2) Custom"
+	echo "   3) Random [49152-65535]"
+	until [[ $PORT_CHOICE =~ ^[1-3]$ ]]; do
+		read -rp "Port choice [1-3]: " -e -i 1 PORT_CHOICE
+	done
+	case $PORT_CHOICE in
+	1)
+		PORT="1194"
+		;;
+	2)
+		until [[ $PORT =~ ^[0-9]+$ ]] && [ "$PORT" -ge 1 ] && [ "$PORT" -le 65535 ]; do
+			read -rp "Custom port [1-65535]: " -e -i 1194 PORT
+		done
+		;;
+	3)
+		# Generate random number within private ports range
+		PORT=$(shuf -i49152-65535 -n1)
+		echo "Random Port: $PORT"
+		;;
+	esac
+	echo ""
+	echo "What protocol do you want OpenVPN to use?"
+	echo "UDP is faster. Unless it is not available, you shouldn't use TCP."
+	echo "   1) UDP"
+	echo "   2) TCP"
+	until [[ $PROTOCOL_CHOICE =~ ^[1-2]$ ]]; do
+		read -rp "Protocol [1-2]: " -e -i 1 PROTOCOL_CHOICE
+	done
+	case $PROTOCOL_CHOICE in
+	1)
+		PROTOCOL="udp"
+		;;
+	2)
+		PROTOCOL="tcp"
+		;;
+	esac
+	echo ""
+	echo "What DNS resolvers do you want to use with the VPN?"
+	echo "   1) Current system resolvers (from /etc/resolv.conf)"
+	echo "   2) Self-hosted DNS Resolver (Unbound)"
+	echo "   3) Cloudflare (Anycast: worldwide)"
+	echo "   4) Quad9 (Anycast: worldwide)"
+	echo "   5) Quad9 uncensored (Anycast: worldwide)"
+	echo "   6) FDN (France)"
+	echo "   7) DNS.WATCH (Germany)"
+	echo "   8) OpenDNS (Anycast: worldwide)"
+	echo "   9) Google (Anycast: worldwide)"
+	echo "   10) Yandex Basic (Russia)"
+	echo "   11) AdGuard DNS (Anycast: worldwide)"
+	echo "   12) NextDNS (Anycast: worldwide)"
+	echo "   13) Custom"
+	until [[ $DNS =~ ^[0-9]+$ ]] && [ "$DNS" -ge 1 ] && [ "$DNS" -le 13 ]; do
+		read -rp "DNS [1-12]: " -e -i 11 DNS
+		if [[ $DNS == 2 ]] && [[ -e /etc/unbound/unbound.conf ]]; then
+			echo ""
+			echo "Unbound is already installed."
+			echo "You can allow the script to configure it in order to use it from your OpenVPN clients"
+			echo "We will simply add a second server to /etc/unbound/unbound.conf for the OpenVPN subnet."
+			echo "No changes are made to the current configuration."
+			echo ""
+
+			until [[ $CONTINUE =~ (y|n) ]]; do
+				read -rp "Apply configuration changes to Unbound? [y/n]: " -e CONTINUE
+			done
+			if [[ $CONTINUE == "n" ]]; then
+				# Break the loop and cleanup
+				unset DNS
+				unset CONTINUE
+			fi
+		elif [[ $DNS == "13" ]]; then
+			until [[ $DNS1 =~ ^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$ ]]; do
+				read -rp "Primary DNS: " -e DNS1
+			done
+			until [[ $DNS2 =~ ^((25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.){3}(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)$ ]]; do
+				read -rp "Secondary DNS (optional): " -e DNS2
+				if [[ $DNS2 == "" ]]; then
+					break
+				fi
+			done
+		fi
+	done
+	echo ""
+	echo "Do you want to use compression? It is not recommended since the VORACLE attack make use of it."
+	until [[ $COMPRESSION_ENABLED =~ (y|n) ]]; do
+		read -rp"Enable compression? [y/n]: " -e -i n COMPRESSION_ENABLED
+	done
+	if [[ $COMPRESSION_ENABLED == "y" ]]; then
+		echo "Choose which compression algorithm you want to use: (they are ordered by efficiency)"
+		echo "   1) LZ4-v2"
+		echo "   2) LZ4"
+		echo "   3) LZ0"
+		until [[ $COMPRESSION_CHOICE =~ ^[1-3]$ ]]; do
+			read -rp"Compression algorithm [1-3]: " -e -i 1 COMPRESSION_CHOICE
+		done
+		case $COMPRESSION_CHOICE in
+		1)
+			COMPRESSION_ALG="lz4-v2"
+			;;
+		2)
+			COMPRESSION_ALG="lz4"
+			;;
+		3)
+			COMPRESSION_ALG="lzo"
+			;;
+		esac
+	fi
+	echo ""
+	echo "Do you want to customize encryption settings?"
+	echo "Unless you know what you're doing, you should stick with the default parameters provided by the script."
+	echo "Note that whatever you choose, all the choices presented in the script are safe. (Unlike OpenVPN's defaults)"
+	echo "See https://github.com/angristan/openvpn-install#security-and-encryption to learn more."
+	echo ""
+	until [[ $CUSTOMIZE_ENC =~ (y|n) ]]; do
+		read -rp "Customize encryption settings? [y/n]: " -e -i n CUSTOMIZE_ENC
+	done
+	if [[ $CUSTOMIZE_ENC == "n" ]]; then
+		# Use default, sane and fast parameters
+		CIPHER="AES-128-GCM"
+		CERT_TYPE="1" # ECDSA
+		CERT_CURVE="prime256v1"
+		CC_CIPHER="TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256"
+		DH_TYPE="1" # ECDH
+		DH_CURVE="prime256v1"
+		HMAC_ALG="SHA256"
+		TLS_SIG="1" # tls-crypt
+	else
+		echo ""
+		echo "Choose which cipher you want to use for the data channel:"
+		echo "   1) AES-128-GCM (recommended)"
+		echo "   2) AES-192-GCM"
+		echo "   3) AES-256-GCM"
+		echo "   4) AES-128-CBC"
+		echo "   5) AES-192-CBC"
+		echo "   6) AES-256-CBC"
+		until [[ $CIPHER_CHOICE =~ ^[1-6]$ ]]; do
+			read -rp "Cipher [1-6]: " -e -i 1 CIPHER_CHOICE
+		done
+		case $CIPHER_CHOICE in
+		1)
+			CIPHER="AES-128-GCM"
+			;;
+		2)
+			CIPHER="AES-192-GCM"
+			;;
+		3)
+			CIPHER="AES-256-GCM"
+			;;
+		4)
+			CIPHER="AES-128-CBC"
+			;;
+		5)
+			CIPHER="AES-192-CBC"
+			;;
+		6)
+			CIPHER="AES-256-CBC"
+			;;
+		esac
+		echo ""
+		echo "Choose what kind of certificate you want to use:"
+		echo "   1) ECDSA (recommended)"
+		echo "   2) RSA"
+		until [[ $CERT_TYPE =~ ^[1-2]$ ]]; do
+			read -rp"Certificate key type [1-2]: " -e -i 1 CERT_TYPE
+		done
+		case $CERT_TYPE in
+		1)
+			echo ""
+			echo "Choose which curve you want to use for the certificate's key:"
+			echo "   1) prime256v1 (recommended)"
+			echo "   2) secp384r1"
+			echo "   3) secp521r1"
+			until [[ $CERT_CURVE_CHOICE =~ ^[1-3]$ ]]; do
+				read -rp"Curve [1-3]: " -e -i 1 CERT_CURVE_CHOICE
+			done
+			case $CERT_CURVE_CHOICE in
+			1)
+				CERT_CURVE="prime256v1"
+				;;
+			2)
+				CERT_CURVE="secp384r1"
+				;;
+			3)
+				CERT_CURVE="secp521r1"
+				;;
+			esac
+			;;
+		2)
+			echo ""
+			echo "Choose which size you want to use for the certificate's RSA key:"
+			echo "   1) 2048 bits (recommended)"
+			echo "   2) 3072 bits"
+			echo "   3) 4096 bits"
+			until [[ $RSA_KEY_SIZE_CHOICE =~ ^[1-3]$ ]]; do
+				read -rp "RSA key size [1-3]: " -e -i 1 RSA_KEY_SIZE_CHOICE
+			done
+			case $RSA_KEY_SIZE_CHOICE in
+			1)
+				RSA_KEY_SIZE="2048"
+				;;
+			2)
+				RSA_KEY_SIZE="3072"
+				;;
+			3)
+				RSA_KEY_SIZE="4096"
+				;;
+			esac
+			;;
+		esac
+		echo ""
+		echo "Choose which cipher you want to use for the control channel:"
+		case $CERT_TYPE in
+		1)
+			echo "   1) ECDHE-ECDSA-AES-128-GCM-SHA256 (recommended)"
+			echo "   2) ECDHE-ECDSA-AES-256-GCM-SHA384"
+			until [[ $CC_CIPHER_CHOICE =~ ^[1-2]$ ]]; do
+				read -rp"Control channel cipher [1-2]: " -e -i 1 CC_CIPHER_CHOICE
+			done
+			case $CC_CIPHER_CHOICE in
+			1)
+				CC_CIPHER="TLS-ECDHE-ECDSA-WITH-AES-128-GCM-SHA256"
+				;;
+			2)
+				CC_CIPHER="TLS-ECDHE-ECDSA-WITH-AES-256-GCM-SHA384"
+				;;
+			esac
+			;;
+		2)
+			echo "   1) ECDHE-RSA-AES-128-GCM-SHA256 (recommended)"
+			echo "   2) ECDHE-RSA-AES-256-GCM-SHA384"
+			until [[ $CC_CIPHER_CHOICE =~ ^[1-2]$ ]]; do
+				read -rp"Control channel cipher [1-2]: " -e -i 1 CC_CIPHER_CHOICE
+			done
+			case $CC_CIPHER_CHOICE in
+			1)
+				CC_CIPHER="TLS-ECDHE-RSA-WITH-AES-128-GCM-SHA256"
+				;;
+			2)
+				CC_CIPHER="TLS-ECDHE-RSA-WITH-AES-256-GCM-SHA384"
+				;;
+			esac
+			;;
+		esac
+		echo ""
+		echo "Choose what kind of Diffie-Hellman key you want to use:"
+		echo "   1) ECDH (recommended)"
+		echo "   2) DH"
+		until [[ $DH_TYPE =~ [1-2] ]]; do
+			read -rp"DH key type [1-2]: " -e -i 1 DH_TYPE
+		done
+		case $DH_TYPE in
+		1)
+			echo ""
+			echo "Choose which curve you want to use for the ECDH key:"
+			echo "   1) prime256v1 (recommended)"
+			echo "   2) secp384r1"
+			echo "   3) secp521r1"
+			while [[ $DH_CURVE_CHOICE != "1" && $DH_CURVE_CHOICE != "2" && $DH_CURVE_CHOICE != "3" ]]; do
+				read -rp"Curve [1-3]: " -e -i 1 DH_CURVE_CHOICE
+			done
+			case $DH_CURVE_CHOICE in
+			1)
+				DH_CURVE="prime256v1"
+				;;
+			2)
+				DH_CURVE="secp384r1"
+				;;
+			3)
+				DH_CURVE="secp521r1"
+				;;
+			esac
+			;;
+		2)
+			echo ""
+			echo "Choose what size of Diffie-Hellman key you want to use:"
+			echo "   1) 2048 bits (recommended)"
+			echo "   2) 3072 bits"
+			echo "   3) 4096 bits"
+			until [[ $DH_KEY_SIZE_CHOICE =~ ^[1-3]$ ]]; do
+				read -rp "DH key size [1-3]: " -e -i 1 DH_KEY_SIZE_CHOICE
+			done
+			case $DH_KEY_SIZE_CHOICE in
+			1)
+				DH_KEY_SIZE="2048"
+				;;
+			2)
+				DH_KEY_SIZE="3072"
+				;;
+			3)
+				DH_KEY_SIZE="4096"
+				;;
+			esac
+			;;
+		esac
+		echo ""
+		# The "auth" options behaves differently with AEAD ciphers
+		if [[ $CIPHER =~ CBC$ ]]; then
+			echo "The digest algorithm authenticates data channel packets and tls-auth packets from the control channel."
+		elif [[ $CIPHER =~ GCM$ ]]; then
+			echo "The digest algorithm authenticates tls-auth packets from the control channel."
+		fi
+		echo "Which digest algorithm do you want to use for HMAC?"
+		echo "   1) SHA-256 (recommended)"
+		echo "   2) SHA-384"
+		echo "   3) SHA-512"
+		until [[ $HMAC_ALG_CHOICE =~ ^[1-3]$ ]]; do
+			read -rp "Digest algorithm [1-3]: " -e -i 1 HMAC_ALG_CHOICE
+		done
+		case $HMAC_ALG_CHOICE in
+		1)
+			HMAC_ALG="SHA256"
+			;;
+		2)
+			HMAC_ALG="SHA384"
+			;;
+		3)
+			HMAC_ALG="SHA512"
+			;;
+		esac
+		echo ""
+		echo "You can add an additional layer of security to the control channel with tls-auth and tls-crypt"
+		echo "tls-auth authenticates the packets, while tls-crypt authenticate and encrypt them."
+		echo "   1) tls-crypt (recommended)"
+		echo "   2) tls-auth"
+		until [[ $TLS_SIG =~ [1-2] ]]; do
+			read -rp "Control channel additional security mechanism [1-2]: " -e -i 1 TLS_SIG
+		done
+	fi
+	echo ""
+	echo "Okay, that was all I needed. We are ready to setup your OpenVPN server now."
+	echo "You will be able to generate a client at the end of the installation."
+	APPROVE_INSTALL=${APPROVE_INSTALL:-n}
+	if [[ $APPROVE_INSTALL =~ n ]]; then
+		read -n1 -r -p "Press any key to continue..."
+	fi
+}
+
+function installOpenVPN() {
+	if [[ $AUTO_INSTALL == "y" ]]; then
+		# Set default choices so that no questions will be asked.
+		APPROVE_INSTALL=${APPROVE_INSTALL:-y}
+		APPROVE_IP=${APPROVE_IP:-y}
+		IPV6_SUPPORT=${IPV6_SUPPORT:-n}
+		PORT_CHOICE=${PORT_CHOICE:-1}
+		PROTOCOL_CHOICE=${PROTOCOL_CHOICE:-1}
+		DNS=${DNS:-1}
+		COMPRESSION_ENABLED=${COMPRESSION_ENABLED:-n}
+		CUSTOMIZE_ENC=${CUSTOMIZE_ENC:-n}
+		CLIENT=${CLIENT:-client}
+		PASS=${PASS:-1}
+		CONTINUE=${CONTINUE:-y}
+
+		# Behind NAT, we'll default to the publicly reachable IPv4/IPv6.
+		if [[ $IPV6_SUPPORT == "y" ]]; then
+			PUBLIC_IP=$(curl https://ifconfig.co)
+		else
+			PUBLIC_IP=$(curl -4 https://ifconfig.co)
+		fi
+		ENDPOINT=${ENDPOINT:-$PUBLIC_IP}
+	fi
+
+	# Run setup questions first, and set other variales if auto-install
+	installQuestions
+
+	# Get the "public" interface from the default route
+	NIC=$(ip -4 route ls | grep default | grep -Po '(?<=dev )(\S+)' | head -1)
+	if [[ -z $NIC ]] && [[ $IPV6_SUPPORT == 'y' ]]; then
+		NIC=$(ip -6 route show default | sed -ne 's/^default .* dev \([^ ]*\) .*$/\1/p')
+	fi
+
+	# $NIC can not be empty for script rm-openvpn-rules.sh
+	if [[ -z $NIC ]]; then
+		echo
+		echo "Can not detect public interface."
+		echo "This needs for setup MASQUERADE."
+		until [[ $CONTINUE =~ (y|n) ]]; do
+			read -rp "Continue? [y/n]: " -e CONTINUE
+		done
+		if [[ $CONTINUE == "n" ]]; then
+			exit 1
+		fi
+	fi
+
+	# If OpenVPN isn't installed yet, install it. This script is more-or-less
+	# idempotent on multiple runs, but will only install OpenVPN from upstream
+	# the first time.
+	if [[ ! -e /etc/openvpn/server.conf ]]; then
+		if [[ $OS =~ (debian|ubuntu) ]]; then
+			apt-get update
+			apt-get -y install ca-certificates gnupg
+			# We add the OpenVPN repo to get the latest version.
+			if [[ $VERSION_ID == "16.04" ]]; then
+				echo "deb http://build.openvpn.net/debian/openvpn/stable xenial main" >/etc/apt/sources.list.d/openvpn.list
+				wget -O - https://swupdate.openvpn.net/repos/repo-public.gpg | apt-key add -
+				apt-get update
+			fi
+			# Ubuntu > 16.04 and Debian > 8 have OpenVPN >= 2.4 without the need of a third party repository.
+			apt-get install -y openvpn iptables openssl wget ca-certificates curl
+		elif [[ $OS == 'centos' ]]; then
+			yum install -y epel-release
+			yum install -y openvpn iptables openssl wget ca-certificates curl tar 'policycoreutils-python*'
+		elif [[ $OS == 'amzn' ]]; then
+			amazon-linux-extras install -y epel
+			yum install -y openvpn iptables openssl wget ca-certificates curl
+		elif [[ $OS == 'fedora' ]]; then
+			dnf install -y openvpn iptables openssl wget ca-certificates curl policycoreutils-python-utils
+		elif [[ $OS == 'arch' ]]; then
+			# Install required dependencies and upgrade the system
+			pacman --needed --noconfirm -Syu openvpn iptables openssl wget ca-certificates curl
+		fi
+		# An old version of easy-rsa was available by default in some openvpn packages
+		if [[ -d /etc/openvpn/easy-rsa/ ]]; then
+			rm -rf /etc/openvpn/easy-rsa/
+		fi
+	fi
+
+	# Find out if the machine uses nogroup or nobody for the permissionless group
+	if grep -qs "^nogroup:" /etc/group; then
+		NOGROUP=nogroup
+	else
+		NOGROUP=nobody
+	fi
+
+	# Install the latest version of easy-rsa from source, if not already installed.
+	if [[ ! -d /etc/openvpn/easy-rsa/ ]]; then
+		local version="3.0.7"
+		wget -O ~/easy-rsa.tgz https://github.com/OpenVPN/easy-rsa/releases/download/v${version}/EasyRSA-${version}.tgz
+		mkdir -p /etc/openvpn/easy-rsa
+		tar xzf ~/easy-rsa.tgz --strip-components=1 --directory /etc/openvpn/easy-rsa
+		rm -f ~/easy-rsa.tgz
+
+		cd /etc/openvpn/easy-rsa/ || return
+		case $CERT_TYPE in
+		1)
+			echo "set_var EASYRSA_ALGO ec" >vars
+			echo "set_var EASYRSA_CURVE $CERT_CURVE" >>vars
+			;;
+		2)
+			echo "set_var EASYRSA_KEY_SIZE $RSA_KEY_SIZE" >vars
+			;;
+		esac
+
+		# Generate a random, alphanumeric identifier of 16 characters for CN and one for server name
+		SERVER_CN="cn_$(head /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 16 | head -n 1)"
+		echo "$SERVER_CN" >SERVER_CN_GENERATED
+		SERVER_NAME="server_$(head /dev/urandom | tr -dc 'a-zA-Z0-9' | fold -w 16 | head -n 1)"
+		echo "$SERVER_NAME" >SERVER_NAME_GENERATED
+
+		echo "set_var EASYRSA_REQ_CN $SERVER_CN" >>vars
+
+		# Create the PKI, set up the CA, the DH params and the server certificate
+		./easyrsa init-pki
+		./easyrsa --batch build-ca nopass
+
+		if [[ $DH_TYPE == "2" ]]; then
+			# ECDH keys are generated on-the-fly so we don't need to generate them beforehand
+			openssl dhparam -out dh.pem $DH_KEY_SIZE
+		fi
+
+		./easyrsa build-server-full "$SERVER_NAME" nopass
+		EASYRSA_CRL_DAYS=3650 ./easyrsa gen-crl
+
+		case $TLS_SIG in
+		1)
+			# Generate tls-crypt key
+			openvpn --genkey --secret /etc/openvpn/tls-crypt.key
+			;;
+		2)
+			# Generate tls-auth key
+			openvpn --genkey --secret /etc/openvpn/tls-auth.key
+			;;
+		esac
+	else
+		# If easy-rsa is already installed, grab the generated SERVER_NAME
+		# for client configs
+		cd /etc/openvpn/easy-rsa/ || return
+		SERVER_NAME=$(cat SERVER_NAME_GENERATED)
+	fi
+
+	# Move all the generated files
+	cp pki/ca.crt pki/private/ca.key "pki/issued/$SERVER_NAME.crt" "pki/private/$SERVER_NAME.key" /etc/openvpn/easy-rsa/pki/crl.pem /etc/openvpn
+	if [[ $DH_TYPE == "2" ]]; then
+		cp dh.pem /etc/openvpn
+	fi
+
+	# Make cert revocation list readable for non-root
+	chmod 644 /etc/openvpn/crl.pem
+
+	# Generate server.conf
+	echo "port $PORT" >/etc/openvpn/server.conf
+	if [[ $IPV6_SUPPORT == 'n' ]]; then
+		echo "proto $PROTOCOL" >>/etc/openvpn/server.conf
+	elif [[ $IPV6_SUPPORT == 'y' ]]; then
+		echo "proto ${PROTOCOL}6" >>/etc/openvpn/server.conf
+	fi
+
+	echo "dev tun
 user nobody
 group $NOGROUP
 persist-key
@@ -494,200 +768,557 @@ persist-tun
 keepalive 10 120
 topology subnet
 server 10.8.0.0 255.255.255.0
-    ifconfig-pool-persist ipp.txt" >> /etc/openvpn/server.conf
-    # DNS resolvers
-    case $DNS in
-        1)
-            # Obtain the resolvers from resolv.conf and use them for OpenVPN
-            grep -v '#' /etc/resolv.conf | grep 'nameserver' | grep -E -o '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' | while read line; do
-                echo "push \"dhcp-option DNS $line\"" >> /etc/openvpn/server.conf
-            done
-            ;;
-        2) #Quad9
-            echo 'push "dhcp-option DNS 9.9.9.9"' >> /etc/openvpn/server.conf
-            ;;
-        3) #FDN
-            echo 'push "dhcp-option DNS 80.67.169.12"' >> /etc/openvpn/server.conf
-            echo 'push "dhcp-option DNS 80.67.169.40"' >> /etc/openvpn/server.conf
-            ;;
-        4) #DNS.WATCH
-            echo 'push "dhcp-option DNS 84.200.69.80"' >> /etc/openvpn/server.conf
-            echo 'push "dhcp-option DNS 84.200.70.40"' >> /etc/openvpn/server.conf
-            ;;
-        5) #OpenDNS
-            echo 'push "dhcp-option DNS 208.67.222.222"' >> /etc/openvpn/server.conf
-            echo 'push "dhcp-option DNS 208.67.220.220"' >> /etc/openvpn/server.conf
-            ;;
-        6) #Google
-            echo 'push "dhcp-option DNS 8.8.8.8"' >> /etc/openvpn/server.conf
-            echo 'push "dhcp-option DNS 8.8.4.4"' >> /etc/openvpn/server.conf
-            ;;
-        7) #Yandex Basic
-            echo 'push "dhcp-option DNS 77.88.8.8"' >> /etc/openvpn/server.conf
-            echo 'push "dhcp-option DNS 77.88.8.1"' >> /etc/openvpn/server.conf
-            ;;
-        8) #AdGuard DNS
-            echo 'push "dhcp-option DNS 176.103.130.130"' >> /etc/openvpn/server.conf
-            echo 'push "dhcp-option DNS 176.103.130.131"' >> /etc/openvpn/server.conf
-            ;;
-    esac
-    echo 'push "redirect-gateway def1 bypass-dhcp" '>> /etc/openvpn/server.conf
-    echo "crl-verify crl.pem
+ifconfig-pool-persist ipp.txt" >>/etc/openvpn/server.conf
+
+	# DNS resolvers
+	case $DNS in
+	1) # Current system resolvers
+		# Locate the proper resolv.conf
+		# Needed for systems running systemd-resolved
+		if grep -q "127.0.0.53" "/etc/resolv.conf"; then
+			RESOLVCONF='/run/systemd/resolve/resolv.conf'
+		else
+			RESOLVCONF='/etc/resolv.conf'
+		fi
+		# Obtain the resolvers from resolv.conf and use them for OpenVPN
+		sed -ne 's/^nameserver[[:space:]]\+\([^[:space:]]\+\).*$/\1/p' $RESOLVCONF | while read -r line; do
+			# Copy, if it's a IPv4 |or| if IPv6 is enabled, IPv4/IPv6 does not matter
+			if [[ $line =~ ^[0-9.]*$ ]] || [[ $IPV6_SUPPORT == 'y' ]]; then
+				echo "push \"dhcp-option DNS $line\"" >>/etc/openvpn/server.conf
+			fi
+		done
+		;;
+	2) # Self-hosted DNS resolver (Unbound)
+		echo 'push "dhcp-option DNS 10.8.0.1"' >>/etc/openvpn/server.conf
+		if [[ $IPV6_SUPPORT == 'y' ]]; then
+			echo 'push "dhcp-option DNS fd42:42:42:42::1"' >>/etc/openvpn/server.conf
+		fi
+		;;
+	3) # Cloudflare
+		echo 'push "dhcp-option DNS 1.0.0.1"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 1.1.1.1"' >>/etc/openvpn/server.conf
+		;;
+	4) # Quad9
+		echo 'push "dhcp-option DNS 9.9.9.9"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 149.112.112.112"' >>/etc/openvpn/server.conf
+		;;
+	5) # Quad9 uncensored
+		echo 'push "dhcp-option DNS 9.9.9.10"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 149.112.112.10"' >>/etc/openvpn/server.conf
+		;;
+	6) # FDN
+		echo 'push "dhcp-option DNS 80.67.169.40"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 80.67.169.12"' >>/etc/openvpn/server.conf
+		;;
+	7) # DNS.WATCH
+		echo 'push "dhcp-option DNS 84.200.69.80"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 84.200.70.40"' >>/etc/openvpn/server.conf
+		;;
+	8) # OpenDNS
+		echo 'push "dhcp-option DNS 208.67.222.222"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 208.67.220.220"' >>/etc/openvpn/server.conf
+		;;
+	9) # Google
+		echo 'push "dhcp-option DNS 8.8.8.8"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 8.8.4.4"' >>/etc/openvpn/server.conf
+		;;
+	10) # Yandex Basic
+		echo 'push "dhcp-option DNS 77.88.8.8"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 77.88.8.1"' >>/etc/openvpn/server.conf
+		;;
+	11) # AdGuard DNS
+		echo 'push "dhcp-option DNS 94.140.14.14"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 94.140.15.15"' >>/etc/openvpn/server.conf
+		;;
+	12) # NextDNS
+		echo 'push "dhcp-option DNS 45.90.28.167"' >>/etc/openvpn/server.conf
+		echo 'push "dhcp-option DNS 45.90.30.167"' >>/etc/openvpn/server.conf
+		;;
+	13) # Custom DNS
+		echo "push \"dhcp-option DNS $DNS1\"" >>/etc/openvpn/server.conf
+		if [[ $DNS2 != "" ]]; then
+			echo "push \"dhcp-option DNS $DNS2\"" >>/etc/openvpn/server.conf
+		fi
+		;;
+	esac
+	echo 'push "redirect-gateway def1 bypass-dhcp"' >>/etc/openvpn/server.conf
+
+	# IPv6 network settings if needed
+	if [[ $IPV6_SUPPORT == 'y' ]]; then
+		echo 'server-ipv6 fd42:42:42:42::/112
+tun-ipv6
+push tun-ipv6
+push "route-ipv6 2000::/3"
+push "redirect-gateway ipv6"' >>/etc/openvpn/server.conf
+	fi
+
+	if [[ $COMPRESSION_ENABLED == "y" ]]; then
+		echo "compress $COMPRESSION_ALG" >>/etc/openvpn/server.conf
+	fi
+
+	if [[ $DH_TYPE == "1" ]]; then
+		echo "dh none" >>/etc/openvpn/server.conf
+		echo "ecdh-curve $DH_CURVE" >>/etc/openvpn/server.conf
+	elif [[ $DH_TYPE == "2" ]]; then
+		echo "dh dh.pem" >>/etc/openvpn/server.conf
+	fi
+
+	case $TLS_SIG in
+	1)
+		echo "tls-crypt tls-crypt.key" >>/etc/openvpn/server.conf
+		;;
+	2)
+		echo "tls-auth tls-auth.key 0" >>/etc/openvpn/server.conf
+		;;
+	esac
+
+	echo "crl-verify crl.pem
 ca ca.crt
-cert server.crt
-key server.key
-tls-auth tls-auth.key 0
-dh dh.pem
-auth SHA256
-$CIPHER
+cert $SERVER_NAME.crt
+key $SERVER_NAME.key
+auth $HMAC_ALG
+cipher $CIPHER
+ncp-ciphers $CIPHER
 tls-server
 tls-version-min 1.2
-tls-cipher TLS-DHE-RSA-WITH-AES-128-GCM-SHA256
-status openvpn.log
-    verb 3" >> /etc/openvpn/server.conf
+tls-cipher $CC_CIPHER
+client-config-dir /etc/openvpn/ccd
+status /var/log/openvpn/status.log
+verb 3" >>/etc/openvpn/server.conf
 
-    # Create the sysctl configuration file if needed (mainly for Arch Linux)
-    if [[ ! -e $SYSCTL ]]; then
-        touch $SYSCTL
-    fi
+	# Create client-config-dir dir
+	mkdir -p /etc/openvpn/ccd
+	# Create log dir
+	mkdir -p /var/log/openvpn
 
-    # Enable net.ipv4.ip_forward for the system
-    sed -i '/\<net.ipv4.ip_forward\>/c\net.ipv4.ip_forward=1' $SYSCTL
-    if ! grep -q "\<net.ipv4.ip_forward\>" $SYSCTL; then
-        echo 'net.ipv4.ip_forward=1' >> $SYSCTL
-    fi
-    # Avoid an unneeded reboot
-    echo 1 > /proc/sys/net/ipv4/ip_forward
-    # Set NAT for the VPN subnet
-    iptables -t nat -A POSTROUTING -o $NIC -s 10.8.0.0/24 -j MASQUERADE
-    # Save persitent iptables rules
-    iptables-save > $IPTABLES
-    if pgrep firewalld; then
-        # We don't use --add-service=openvpn because that would only work with
-        # the default port. Using both permanent and not permanent rules to
-        # avoid a firewalld reload.
-        if [[ "$PROTOCOL" = 'UDP' ]]; then
-            firewall-cmd --zone=public --add-port=$PORT/udp
-            firewall-cmd --permanent --zone=public --add-port=$PORT/udp
-        elif [[ "$PROTOCOL" = 'TCP' ]]; then
-            firewall-cmd --zone=public --add-port=$PORT/tcp
-            firewall-cmd --permanent --zone=public --add-port=$PORT/tcp
-        fi
-        firewall-cmd --zone=trusted --add-source=10.8.0.0/24
-        firewall-cmd --permanent --zone=trusted --add-source=10.8.0.0/24
-    fi
-    if iptables -L -n | grep -qE 'REJECT|DROP'; then
-        # If iptables has at least one REJECT rule, we asume this is needed.
-        # Not the best approach but I can't think of other and this shouldn't
-        # cause problems.
-        if [[ "$PROTOCOL" = 'UDP' ]]; then
-            iptables -I INPUT -p udp --dport $PORT -j ACCEPT
-        elif [[ "$PROTOCOL" = 'TCP' ]]; then
-            iptables -I INPUT -p tcp --dport $PORT -j ACCEPT
-        fi
-        iptables -I FORWARD -s 10.8.0.0/24 -j ACCEPT
-        iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
-        # Save persitent OpenVPN rules
-        iptables-save > $IPTABLES
-    fi
-    # If SELinux is enabled and a custom port was selected, we need this
-    if hash sestatus 2>/dev/null; then
-        if sestatus | grep "Current mode" | grep -qs "enforcing"; then
-            if [[ "$PORT" != '1194' ]]; then
-                # semanage isn't available in CentOS 6 by default
-                if ! hash semanage 2>/dev/null; then
-                    yum install policycoreutils-python -y
-                fi
-                if [[ "$PROTOCOL" = 'UDP' ]]; then
-                    semanage port -a -t openvpn_port_t -p udp $PORT
-                elif [[ "$PROTOCOL" = 'TCP' ]]; then
-                    semanage port -a -t openvpn_port_t -p tcp $PORT
-                fi
-            fi
-        fi
-    fi
-    # And finally, restart OpenVPN
-    if [[ "$OS" = 'debian' ]]; then
-        # Little hack to check for systemd
-        if pgrep systemd-journal; then
-            if [[ "$VERSION_ID" = 'VERSION_ID="9"' ]]; then
-                #Workaround to fix OpenVPN service on Debian 9 OpenVZ
-                sed -i 's|LimitNPROC|#LimitNPROC|' /lib/systemd/system/openvpn-server\@.service
-                sed -i 's|/etc/openvpn/server|/etc/openvpn|' /lib/systemd/system/openvpn-server\@.service
-                sed -i 's|%i.conf|server.conf|' /lib/systemd/system/openvpn-server\@.service
-                systemctl daemon-reload
-                systemctl restart openvpn-server\@openvpn.service
-                systemctl enable openvpn-server\@openvpn.service
-            else
-                sed -i 's|LimitNPROC|#LimitNPROC|' /lib/systemd/system/openvpn\@.service
-                systemctl daemon-reload
-                systemctl restart openvpn\@server.service
-            fi
-        else
-            /etc/init.d/openvpn restart
-        fi
-    else
-        if pgrep systemd-journal; then
-            if [[ "$OS" = 'arch' ]] || [[ "$VERSION_ID" = 'VERSION_ID="16.04"' ]]; then
-                #Workaround to avoid rewriting the entire script for Arch
-                sed -i 's|LimitNPROC|#LimitNPROC|' /usr/lib/systemd/system/openvpn-server\@.service
-                sed -i 's|/etc/openvpn/server|/etc/openvpn|' /usr/lib/systemd/system/openvpn-server\@.service
-                sed -i 's|%i.conf|server.conf|' /usr/lib/systemd/system/openvpn-server\@.service
-                systemctl daemon-reload
-                systemctl restart openvpn-server\@openvpn.service
-                systemctl enable openvpn-server\@openvpn.service
-            else
-                systemctl restart openvpn\@server.service
-                systemctl enable openvpn\@server.service
-            fi
-        else
-            service openvpn restart
-            chkconfig openvpn on
-        fi
-    fi
-    # Try to detect a NATed connection and ask about it to potential LowEndSpirit/Scaleway users
-    EXTERNALIP=$(wget -qO- ipv4.icanhazip.com)
-    if [[ "$IP" != "$EXTERNALIP" ]]; then
-        echo ""
-        echo "Looks like your server is behind a NAT!"
-        echo ""
-        echo "If your server is NATed (e.g. LowEndSpirit, Scaleway, or behind a router),"
-        echo "then I need to know the address that can be used to access it from outside."
-        echo "If that's not the case, just ignore this and leave the next field blank"
-        read -p "External IP or domain name: " -e USEREXTERNALIP
-        if [[ "$USEREXTERNALIP" != "" ]]; then
-            IP=$USEREXTERNALIP
-        fi
-    fi
-    # client-template.txt is created so we have a template to add further users later
-    echo "client" > /etc/openvpn/client-template.txt
-    if [[ "$PROTOCOL" = 'UDP' ]]; then
-        echo "proto udp" >> /etc/openvpn/client-template.txt
-    elif [[ "$PROTOCOL" = 'TCP' ]]; then
-        echo "proto tcp-client" >> /etc/openvpn/client-template.txt
-    fi
-    echo "remote $IP $PORT
+	# Enable routing
+	echo 'net.ipv4.ip_forward=1' >/etc/sysctl.d/99-openvpn.conf
+	if [[ $IPV6_SUPPORT == 'y' ]]; then
+		echo 'net.ipv6.conf.all.forwarding=1' >>/etc/sysctl.d/99-openvpn.conf
+	fi
+	# Apply sysctl rules
+	sysctl --system
+
+	# If SELinux is enabled and a custom port was selected, we need this
+	if hash sestatus 2>/dev/null; then
+		if sestatus | grep "Current mode" | grep -qs "enforcing"; then
+			if [[ $PORT != '1194' ]]; then
+				semanage port -a -t openvpn_port_t -p "$PROTOCOL" "$PORT"
+			fi
+		fi
+	fi
+
+	# Finally, restart and enable OpenVPN
+	if [[ $OS == 'arch' || $OS == 'fedora' || $OS == 'centos' ]]; then
+		# Don't modify package-provided service
+		cp /usr/lib/systemd/system/openvpn-server@.service /etc/systemd/system/openvpn-server@.service
+
+		# Workaround to fix OpenVPN service on OpenVZ
+		sed -i 's|LimitNPROC|#LimitNPROC|' /etc/systemd/system/openvpn-server@.service
+		# Another workaround to keep using /etc/openvpn/
+		sed -i 's|/etc/openvpn/server|/etc/openvpn|' /etc/systemd/system/openvpn-server@.service
+		# On fedora, the service hardcodes the ciphers. We want to manage the cipher ourselves, so we remove it from the service
+		if [[ $OS == "fedora" ]]; then
+			sed -i 's|--cipher AES-256-GCM --ncp-ciphers AES-256-GCM:AES-128-GCM:AES-256-CBC:AES-128-CBC:BF-CBC||' /etc/systemd/system/openvpn-server@.service
+		fi
+
+		systemctl daemon-reload
+		systemctl enable openvpn-server@server
+		systemctl restart openvpn-server@server
+	elif [[ $OS == "ubuntu" ]] && [[ $VERSION_ID == "16.04" ]]; then
+		# On Ubuntu 16.04, we use the package from the OpenVPN repo
+		# This package uses a sysvinit service
+		systemctl enable openvpn
+		systemctl start openvpn
+	else
+		# Don't modify package-provided service
+		cp /lib/systemd/system/openvpn\@.service /etc/systemd/system/openvpn\@.service
+
+		# Workaround to fix OpenVPN service on OpenVZ
+		sed -i 's|LimitNPROC|#LimitNPROC|' /etc/systemd/system/openvpn\@.service
+		# Another workaround to keep using /etc/openvpn/
+		sed -i 's|/etc/openvpn/server|/etc/openvpn|' /etc/systemd/system/openvpn\@.service
+
+		systemctl daemon-reload
+		systemctl enable openvpn@server
+		systemctl restart openvpn@server
+	fi
+
+	if [[ $DNS == 2 ]]; then
+		installUnbound
+	fi
+
+	# Add iptables rules in two scripts
+	mkdir -p /etc/iptables
+
+	# Script to add rules
+	echo "#!/bin/sh
+iptables -t nat -I POSTROUTING 1 -s 10.8.0.0/24 -o $NIC -j MASQUERADE
+iptables -I INPUT 1 -i tun0 -j ACCEPT
+iptables -I FORWARD 1 -i $NIC -o tun0 -j ACCEPT
+iptables -I FORWARD 1 -i tun0 -o $NIC -j ACCEPT
+iptables -I INPUT 1 -i $NIC -p $PROTOCOL --dport $PORT -j ACCEPT" >/etc/iptables/add-openvpn-rules.sh
+
+	if [[ $IPV6_SUPPORT == 'y' ]]; then
+		echo "ip6tables -t nat -I POSTROUTING 1 -s fd42:42:42:42::/112 -o $NIC -j MASQUERADE
+ip6tables -I INPUT 1 -i tun0 -j ACCEPT
+ip6tables -I FORWARD 1 -i $NIC -o tun0 -j ACCEPT
+ip6tables -I FORWARD 1 -i tun0 -o $NIC -j ACCEPT
+ip6tables -I INPUT 1 -i $NIC -p $PROTOCOL --dport $PORT -j ACCEPT" >>/etc/iptables/add-openvpn-rules.sh
+	fi
+
+	# Script to remove rules
+	echo "#!/bin/sh
+iptables -t nat -D POSTROUTING -s 10.8.0.0/24 -o $NIC -j MASQUERADE
+iptables -D INPUT -i tun0 -j ACCEPT
+iptables -D FORWARD -i $NIC -o tun0 -j ACCEPT
+iptables -D FORWARD -i tun0 -o $NIC -j ACCEPT
+iptables -D INPUT -i $NIC -p $PROTOCOL --dport $PORT -j ACCEPT" >/etc/iptables/rm-openvpn-rules.sh
+
+	if [[ $IPV6_SUPPORT == 'y' ]]; then
+		echo "ip6tables -t nat -D POSTROUTING -s fd42:42:42:42::/112 -o $NIC -j MASQUERADE
+ip6tables -D INPUT -i tun0 -j ACCEPT
+ip6tables -D FORWARD -i $NIC -o tun0 -j ACCEPT
+ip6tables -D FORWARD -i tun0 -o $NIC -j ACCEPT
+ip6tables -D INPUT -i $NIC -p $PROTOCOL --dport $PORT -j ACCEPT" >>/etc/iptables/rm-openvpn-rules.sh
+	fi
+
+	chmod +x /etc/iptables/add-openvpn-rules.sh
+	chmod +x /etc/iptables/rm-openvpn-rules.sh
+
+	# Handle the rules via a systemd script
+	echo "[Unit]
+Description=iptables rules for OpenVPN
+Before=network-online.target
+Wants=network-online.target
+
+[Service]
+Type=oneshot
+ExecStart=/etc/iptables/add-openvpn-rules.sh
+ExecStop=/etc/iptables/rm-openvpn-rules.sh
+RemainAfterExit=yes
+
+[Install]
+WantedBy=multi-user.target" >/etc/systemd/system/iptables-openvpn.service
+
+	# Enable service and apply rules
+	systemctl daemon-reload
+	systemctl enable iptables-openvpn
+	systemctl start iptables-openvpn
+
+	# If the server is behind a NAT, use the correct IP address for the clients to connect to
+	if [[ $ENDPOINT != "" ]]; then
+		IP=$ENDPOINT
+	fi
+
+	# client-template.txt is created so we have a template to add further users later
+	echo "client" >/etc/openvpn/client-template.txt
+	if [[ $PROTOCOL == 'udp' ]]; then
+		echo "proto udp" >>/etc/openvpn/client-template.txt
+		echo "explicit-exit-notify" >>/etc/openvpn/client-template.txt
+	elif [[ $PROTOCOL == 'tcp' ]]; then
+		echo "proto tcp-client" >>/etc/openvpn/client-template.txt
+	fi
+	echo "remote $IP $PORT
 dev tun
 resolv-retry infinite
 nobind
 persist-key
 persist-tun
 remote-cert-tls server
-auth SHA256
+verify-x509-name $SERVER_NAME name
+auth $HMAC_ALG
 auth-nocache
-$CIPHER
+cipher $CIPHER
 tls-client
 tls-version-min 1.2
-tls-cipher TLS-DHE-RSA-WITH-AES-128-GCM-SHA256
-setenv opt block-outside-dns
-    verb 3" >> /etc/openvpn/client-template.txt
+tls-cipher $CC_CIPHER
+ignore-unknown-option block-outside-dns
+setenv opt block-outside-dns # Prevent Windows 10 DNS leak
+verb 3" >>/etc/openvpn/client-template.txt
 
-    # Generate the custom client.ovpn
-    newclient "$CLIENT"
-    echo ""
-    echo "Finished!"
-    echo ""
-    echo "Your client config is available at $homeDir/$CLIENT.ovpn"
-    echo "If you want to add more clients, you simply need to run this script another time!"
+	if [[ $COMPRESSION_ENABLED == "y" ]]; then
+		echo "compress $COMPRESSION_ALG" >>/etc/openvpn/client-template.txt
+	fi
+
+	# Generate the custom client.ovpn
+	newClient
+	echo "If you want to add more clients, you simply need to run this script another time!"
+}
+
+function newClient() {
+	echo ""
+	echo "Tell me a name for the client."
+	echo "The name must consist of alphanumeric character. It may also include an underscore or a dash."
+
+	until [[ $CLIENT =~ ^[a-zA-Z0-9_-]+$ ]]; do
+		read -rp "Client name: " -e CLIENT
+	done
+
+	echo ""
+	echo "Do you want to protect the configuration file with a password?"
+	echo "(e.g. encrypt the private key with a password)"
+	echo "   1) Add a passwordless client"
+	echo "   2) Use a password for the client"
+
+	until [[ $PASS =~ ^[1-2]$ ]]; do
+		read -rp "Select an option [1-2]: " -e -i 1 PASS
+	done
+
+	CLIENTEXISTS=$(tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep -c -E "/CN=$CLIENT\$")
+	if [[ $CLIENTEXISTS == '1' ]]; then
+		echo ""
+		echo "The specified client CN was already found in easy-rsa, please choose another name."
+		exit
+	else
+		cd /etc/openvpn/easy-rsa/ || return
+		case $PASS in
+		1)
+			./easyrsa build-client-full "$CLIENT" nopass
+			;;
+		2)
+			echo "⚠️ You will be asked for the client password below ⚠️"
+			./easyrsa build-client-full "$CLIENT"
+			;;
+		esac
+		echo "Client $CLIENT added."
+	fi
+
+	# Home directory of the user, where the client configuration (.ovpn) will be written
+	if [ -e "/home/$CLIENT" ]; then # if $1 is a user name
+		homeDir="/home/$CLIENT"
+	elif [ "${SUDO_USER}" ]; then # if not, use SUDO_USER
+		homeDir="/home/${SUDO_USER}"
+	else # if not SUDO_USER, use /root
+		homeDir="/root"
+	fi
+
+	# Determine if we use tls-auth or tls-crypt
+	if grep -qs "^tls-crypt" /etc/openvpn/server.conf; then
+		TLS_SIG="1"
+	elif grep -qs "^tls-auth" /etc/openvpn/server.conf; then
+		TLS_SIG="2"
+	fi
+
+	# Generates the custom client.ovpn
+	cp /etc/openvpn/client-template.txt "$homeDir/$CLIENT.ovpn"
+	{
+		echo "<ca>"
+		cat "/etc/openvpn/easy-rsa/pki/ca.crt"
+		echo "</ca>"
+
+		echo "<cert>"
+		awk '/BEGIN/,/END/' "/etc/openvpn/easy-rsa/pki/issued/$CLIENT.crt"
+		echo "</cert>"
+
+		echo "<key>"
+		cat "/etc/openvpn/easy-rsa/pki/private/$CLIENT.key"
+		echo "</key>"
+
+		case $TLS_SIG in
+		1)
+			echo "<tls-crypt>"
+			cat /etc/openvpn/tls-crypt.key
+			echo "</tls-crypt>"
+			;;
+		2)
+			echo "key-direction 1"
+			echo "<tls-auth>"
+			cat /etc/openvpn/tls-auth.key
+			echo "</tls-auth>"
+			;;
+		esac
+	} >>"$homeDir/$CLIENT.ovpn"
+
+	echo ""
+	echo "The configuration file has been written to $homeDir/$CLIENT.ovpn."
+	echo "Download the .ovpn file and import it in your OpenVPN client."
+
+	exit 0
+}
+
+function revokeClient() {
+	NUMBEROFCLIENTS=$(tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep -c "^V")
+	if [[ $NUMBEROFCLIENTS == '0' ]]; then
+		echo ""
+		echo "You have no existing clients!"
+		exit 1
+	fi
+
+	echo ""
+	echo "Select the existing client certificate you want to revoke"
+	tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep "^V" | cut -d '=' -f 2 | nl -s ') '
+	until [[ $CLIENTNUMBER -ge 1 && $CLIENTNUMBER -le $NUMBEROFCLIENTS ]]; do
+		if [[ $CLIENTNUMBER == '1' ]]; then
+			read -rp "Select one client [1]: " CLIENTNUMBER
+		else
+			read -rp "Select one client [1-$NUMBEROFCLIENTS]: " CLIENTNUMBER
+		fi
+	done
+	CLIENT=$(tail -n +2 /etc/openvpn/easy-rsa/pki/index.txt | grep "^V" | cut -d '=' -f 2 | sed -n "$CLIENTNUMBER"p)
+	cd /etc/openvpn/easy-rsa/ || return
+	./easyrsa --batch revoke "$CLIENT"
+	EASYRSA_CRL_DAYS=3650 ./easyrsa gen-crl
+	rm -f /etc/openvpn/crl.pem
+	cp /etc/openvpn/easy-rsa/pki/crl.pem /etc/openvpn/crl.pem
+	chmod 644 /etc/openvpn/crl.pem
+	find /home/ -maxdepth 2 -name "$CLIENT.ovpn" -delete
+	rm -f "/root/$CLIENT.ovpn"
+	sed -i "/^$CLIENT,.*/d" /etc/openvpn/ipp.txt
+
+	echo ""
+	echo "Certificate for client $CLIENT revoked."
+}
+
+function removeUnbound() {
+	# Remove OpenVPN-related config
+	sed -i '/include: \/etc\/unbound\/openvpn.conf/d' /etc/unbound/unbound.conf
+	rm /etc/unbound/openvpn.conf
+
+	until [[ $REMOVE_UNBOUND =~ (y|n) ]]; do
+		echo ""
+		echo "If you were already using Unbound before installing OpenVPN, I removed the configuration related to OpenVPN."
+		read -rp "Do you want to completely remove Unbound? [y/n]: " -e REMOVE_UNBOUND
+	done
+
+	if [[ $REMOVE_UNBOUND == 'y' ]]; then
+		# Stop Unbound
+		systemctl stop unbound
+
+		if [[ $OS =~ (debian|ubuntu) ]]; then
+			apt-get autoremove --purge -y unbound
+		elif [[ $OS == 'arch' ]]; then
+			pacman --noconfirm -R unbound
+		elif [[ $OS =~ (centos|amzn) ]]; then
+			yum remove -y unbound
+		elif [[ $OS == 'fedora' ]]; then
+			dnf remove -y unbound
+		fi
+
+		rm -rf /etc/unbound/
+
+		echo ""
+		echo "Unbound removed!"
+	else
+		systemctl restart unbound
+		echo ""
+		echo "Unbound wasn't removed."
+	fi
+}
+
+function removeOpenVPN() {
+	echo ""
+	read -rp "Do you really want to remove OpenVPN? [y/n]: " -e -i n REMOVE
+	if [[ $REMOVE == 'y' ]]; then
+		# Get OpenVPN port from the configuration
+		PORT=$(grep '^port ' /etc/openvpn/server.conf | cut -d " " -f 2)
+		PROTOCOL=$(grep '^proto ' /etc/openvpn/server.conf | cut -d " " -f 2)
+
+		# Stop OpenVPN
+		if [[ $OS =~ (fedora|arch|centos) ]]; then
+			systemctl disable openvpn-server@server
+			systemctl stop openvpn-server@server
+			# Remove customised service
+			rm /etc/systemd/system/openvpn-server@.service
+		elif [[ $OS == "ubuntu" ]] && [[ $VERSION_ID == "16.04" ]]; then
+			systemctl disable openvpn
+			systemctl stop openvpn
+		else
+			systemctl disable openvpn@server
+			systemctl stop openvpn@server
+			# Remove customised service
+			rm /etc/systemd/system/openvpn\@.service
+		fi
+
+		# Remove the iptables rules related to the script
+		systemctl stop iptables-openvpn
+		# Cleanup
+		systemctl disable iptables-openvpn
+		rm /etc/systemd/system/iptables-openvpn.service
+		systemctl daemon-reload
+		rm /etc/iptables/add-openvpn-rules.sh
+		rm /etc/iptables/rm-openvpn-rules.sh
+
+		# SELinux
+		if hash sestatus 2>/dev/null; then
+			if sestatus | grep "Current mode" | grep -qs "enforcing"; then
+				if [[ $PORT != '1194' ]]; then
+					semanage port -d -t openvpn_port_t -p "$PROTOCOL" "$PORT"
+				fi
+			fi
+		fi
+
+		if [[ $OS =~ (debian|ubuntu) ]]; then
+			apt-get autoremove --purge -y openvpn
+			if [[ -e /etc/apt/sources.list.d/openvpn.list ]]; then
+				rm /etc/apt/sources.list.d/openvpn.list
+				apt-get update
+			fi
+		elif [[ $OS == 'arch' ]]; then
+			pacman --noconfirm -R openvpn
+		elif [[ $OS =~ (centos|amzn) ]]; then
+			yum remove -y openvpn
+		elif [[ $OS == 'fedora' ]]; then
+			dnf remove -y openvpn
+		fi
+
+		# Cleanup
+		find /home/ -maxdepth 2 -name "*.ovpn" -delete
+		find /root/ -maxdepth 1 -name "*.ovpn" -delete
+		rm -rf /etc/openvpn
+		rm -rf /usr/share/doc/openvpn*
+		rm -f /etc/sysctl.d/99-openvpn.conf
+		rm -rf /var/log/openvpn
+
+		# Unbound
+		if [[ -e /etc/unbound/openvpn.conf ]]; then
+			removeUnbound
+		fi
+		echo ""
+		echo "OpenVPN removed!"
+	else
+		echo ""
+		echo "Removal aborted!"
+	fi
+}
+
+function manageMenu() {
+	echo "Welcome to OpenVPN-install!"
+	echo "The git repository is available at: https://github.com/angristan/openvpn-install"
+	echo ""
+	echo "It looks like OpenVPN is already installed."
+	echo ""
+	echo "What do you want to do?"
+	echo "   1) Add a new user"
+	echo "   2) Revoke existing user"
+	echo "   3) Remove OpenVPN"
+	echo "   4) Exit"
+	until [[ $MENU_OPTION =~ ^[1-4]$ ]]; do
+		read -rp "Select an option [1-4]: " MENU_OPTION
+	done
+
+	case $MENU_OPTION in
+	1)
+		newClient
+		;;
+	2)
+		revokeClient
+		;;
+	3)
+		removeOpenVPN
+		;;
+	4)
+		exit 0
+		;;
+	esac
+}
+
+# Check for root, TUN, OS...
+initialCheck
+
+# Check if OpenVPN is already installed
+if [[ -e /etc/openvpn/server.conf && $AUTO_INSTALL != "y" ]]; then
+	manageMenu
+else
+	installOpenVPN
 fi
-exit 0;