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| #!/bin/bash | |
| # OpenVPN road warrior installer for Debian, Ubuntu and CentOS | |
| # This script will work on Debian, Ubuntu, CentOS and probably other distros | |
| # of the same families, although no support is offered for them. It isn't | |
| # bulletproof but it will probably work if you simply want to setup a VPN on | |
| # your Debian/Ubuntu/CentOS box. It has been designed to be as unobtrusive and | |
| # universal as possible. | |
| # Detect Debian users running the script with "sh" instead of bash | |
| if readlink /proc/$$/exe | grep -qs "dash"; then | |
| echo "This script needs to be run with bash, not sh" | |
| exit 1 | |
| fi | |
| if [[ "$EUID" -ne 0 ]]; then | |
| echo "Sorry, you need to run this as root" | |
| exit 2 | |
| fi | |
| if [[ ! -e /dev/net/tun ]]; then | |
| echo "The TUN device is not available | |
| You need to enable TUN before running this script" | |
| exit 3 | |
| fi | |
| if grep -qs "CentOS release 5" "/etc/redhat-release"; then | |
| echo "CentOS 5 is too old and not supported" | |
| exit 4 | |
| fi | |
| if [[ -e /etc/debian_version ]]; then | |
| OS=debian | |
| GROUPNAME=nogroup | |
| RCLOCAL='/etc/rc.local' | |
| elif [[ -e /etc/centos-release || -e /etc/redhat-release ]]; then | |
| OS=centos | |
| GROUPNAME=nobody | |
| RCLOCAL='/etc/rc.d/rc.local' | |
| else | |
| echo "Looks like you aren't running this installer on Debian, Ubuntu or CentOS" | |
| exit 5 | |
| fi | |
| newclient () { | |
| # Generates the custom client.ovpn | |
| cp /etc/openvpn/client-common.txt ~/$1.ovpn | |
| echo "<ca>" >> ~/$1.ovpn | |
| cat /etc/openvpn/easy-rsa/pki/ca.crt >> ~/$1.ovpn | |
| echo "</ca>" >> ~/$1.ovpn | |
| echo "<cert>" >> ~/$1.ovpn | |
| cat /etc/openvpn/easy-rsa/pki/issued/$1.crt >> ~/$1.ovpn | |
| echo "</cert>" >> ~/$1.ovpn | |
| echo "<key>" >> ~/$1.ovpn | |
| cat /etc/openvpn/easy-rsa/pki/private/$1.key >> ~/$1.ovpn | |
| echo "</key>" >> ~/$1.ovpn | |
| echo "<tls-auth>" >> ~/$1.ovpn | |
| cat /etc/openvpn/ta.key >> ~/$1.ovpn | |
| echo "</tls-auth>" >> ~/$1.ovpn | |
| } | |
| # Try to get our IP from the system and fallback to the Internet. | |
| # I do this to make the script compatible with NATed servers (lowendspirit.com) | |
| # and to avoid getting an IPv6. | |
| IP=$(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 -4qO- "http://whatismyip.akamai.com/") | |
| fi | |
| if [[ -e /etc/openvpn/server.conf ]]; then | |
| while : | |
| do | |
| clear | |
| echo "Looks like OpenVPN is already installed" | |
| echo "" | |
| echo "What do you want to do?" | |
| echo " 1) Add a new user" | |
| echo " 2) Revoke an existing user" | |
| 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 certificate" | |
| 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 $CLIENT added, configuration is available at" ~/"$CLIENT.ovpn" | |
| exit | |
| ;; | |
| 2) | |
| # This option could be documented a bit better and maybe even be simplimplified | |
| # ...but what can I say, I want some sleep too | |
| 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 6 | |
| 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 | |
| # CRL is read with each client connection, when OpenVPN is dropped to nobody | |
| chown nobody:$GROUPNAME /etc/openvpn/crl.pem | |
| echo "" | |
| echo "Certificate for client $CLIENT revoked" | |
| exit | |
| ;; | |
| 3) | |
| echo "" | |
| read -p "Do you really want to remove OpenVPN? [y/n]: " -e -i n REMOVE | |
| if [[ "$REMOVE" = 'y' ]]; then | |
| PORT=$(grep '^port ' /etc/openvpn/server.conf | cut -d " " -f 2) | |
| PROTOCOL=$(grep '^proto ' /etc/openvpn/server.conf | cut -d " " -f 2) | |
| if pgrep firewalld; then | |
| IP=$(firewall-cmd --direct --get-rules ipv4 nat POSTROUTING | grep '\-s 10.8.0.0/24 '"'"'!'"'"' -d 10.8.0.0/24 -j SNAT --to ' | cut -d " " -f 10) | |
| # Using both permanent and not permanent rules to avoid a firewalld reload. | |
| firewall-cmd --zone=public --remove-port=$PORT/$PROTOCOL | |
| firewall-cmd --zone=trusted --remove-source=10.8.0.0/24 | |
| firewall-cmd --permanent --zone=public --remove-port=$PORT/$PROTOCOL | |
| firewall-cmd --permanent --zone=trusted --remove-source=10.8.0.0/24 | |
| firewall-cmd --direct --remove-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP | |
| firewall-cmd --permanent --direct --remove-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP | |
| else | |
| IP=$(grep 'iptables -t nat -A POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to ' $RCLOCAL | cut -d " " -f 14) | |
| iptables -t nat -D POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP | |
| sed -i '/iptables -t nat -A POSTROUTING -s 10.8.0.0\/24 ! -d 10.8.0.0\/24 -j SNAT --to /d' $RCLOCAL | |
| if iptables -L -n | grep -qE '^ACCEPT'; then | |
| iptables -D INPUT -p $PROTOCOL --dport $PORT -j ACCEPT | |
| iptables -D FORWARD -s 10.8.0.0/24 -j ACCEPT | |
| iptables -D FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT | |
| sed -i "/iptables -I INPUT -p $PROTOCOL --dport $PORT -j ACCEPT/d" $RCLOCAL | |
| sed -i "/iptables -I FORWARD -s 10.8.0.0\/24 -j ACCEPT/d" $RCLOCAL | |
| sed -i "/iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT/d" $RCLOCAL | |
| fi | |
| fi | |
| if hash sestatus 2>/dev/null; then | |
| if sestatus | grep "Current mode" | grep -qs "enforcing"; then | |
| if [[ "$PORT" != '1194' || "$PROTOCOL" = 'tcp' ]]; then | |
| semanage port -d -t openvpn_port_t -p $PROTOCOL $PORT | |
| fi | |
| fi | |
| fi | |
| if [[ "$OS" = 'debian' ]]; then | |
| apt-get remove --purge -y openvpn | |
| else | |
| yum remove openvpn -y | |
| fi | |
| rm -rf /etc/openvpn | |
| echo "" | |
| echo "OpenVPN removed!" | |
| else | |
| echo "" | |
| echo "Removal aborted!" | |
| fi | |
| exit | |
| ;; | |
| 4) exit;; | |
| esac | |
| done | |
| else | |
| clear | |
| echo 'Welcome to this quick OpenVPN "road warrior" installer' | |
| 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 "First I need to know the IPv4 address of the network interface you want OpenVPN" | |
| echo "listening to." | |
| read -p "IP address: " -e -i $IP IP | |
| echo "" | |
| echo "Which protocol do you want for OpenVPN connections?" | |
| echo " 1) UDP (recommended)" | |
| echo " 2) TCP" | |
| read -p "Protocol [1-2]: " -e -i 1 PROTOCOL | |
| case $PROTOCOL in | |
| 1) | |
| PROTOCOL=udp | |
| ;; | |
| 2) | |
| PROTOCOL=tcp | |
| ;; | |
| esac | |
| echo "" | |
| echo "What port do you want OpenVPN listening to?" | |
| read -p "Port: " -e -i 1194 PORT | |
| echo "" | |
| echo "Which DNS do you want to use with the VPN?" | |
| echo " 1) Current system resolvers" | |
| echo " 2) Google" | |
| echo " 3) OpenDNS" | |
| echo " 4) NTT" | |
| echo " 5) Hurricane Electric" | |
| echo " 6) Verisign" | |
| read -p "DNS [1-6]: " -e -i 1 DNS | |
| echo "" | |
| echo "Finally, tell me your name for the client certificate" | |
| echo "Please, use one word only, no special characters" | |
| read -p "Client name: " -e -i client CLIENT | |
| echo "" | |
| echo "Okay, that was all I needed. We are ready to setup your OpenVPN server now" | |
| read -n1 -r -p "Press any key to continue..." | |
| if [[ "$OS" = 'debian' ]]; then | |
| apt-get update | |
| apt-get install openvpn iptables openssl ca-certificates -y | |
| else | |
| # Else, the distro is CentOS | |
| yum install epel-release -y | |
| yum install openvpn iptables openssl wget ca-certificates -y | |
| 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 | |
| # 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 ~/ | |
| # Temporal fix for issue #353, which is caused by OpenVPN/easy-rsa#135 | |
| # Will be removed as soon as a new release of easy-rsa is available | |
| sed -i 's/\[\[/\[/g;s/\]\]/\]/g;s/==/=/g' ~/EasyRSA-3.0.3/easyrsa | |
| 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/ | |
| # Create the PKI, set up the CA, the DH params and the server + client certificates | |
| ./easyrsa init-pki | |
| ./easyrsa --batch build-ca nopass | |
| ./easyrsa gen-dh | |
| ./easyrsa build-server-full server nopass | |
| ./easyrsa build-client-full $CLIENT nopass | |
| EASYRSA_CRL_DAYS=3650 ./easyrsa gen-crl | |
| # Move the stuff we need | |
| cp pki/ca.crt pki/private/ca.key pki/dh.pem pki/issued/server.crt pki/private/server.key pki/crl.pem /etc/openvpn | |
| # CRL is read with each client connection, when OpenVPN is dropped to nobody | |
| chown nobody:$GROUPNAME /etc/openvpn/crl.pem | |
| # Generate key for tls-auth | |
| openvpn --genkey --secret /etc/openvpn/ta.key | |
| # Generate server.conf | |
| echo "port $PORT | |
| proto $PROTOCOL | |
| dev tun | |
| sndbuf 0 | |
| rcvbuf 0 | |
| ca ca.crt | |
| cert server.crt | |
| key server.key | |
| dh dh.pem | |
| auth SHA512 | |
| tls-auth ta.key 0 | |
| topology subnet | |
| server 10.8.0.0 255.255.255.0 | |
| ifconfig-pool-persist ipp.txt" > /etc/openvpn/server.conf | |
| echo 'push "redirect-gateway def1 bypass-dhcp"' >> /etc/openvpn/server.conf | |
| # DNS | |
| 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) | |
| 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 | |
| ;; | |
| 3) | |
| 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 | |
| ;; | |
| 4) | |
| echo 'push "dhcp-option DNS 129.250.35.250"' >> /etc/openvpn/server.conf | |
| echo 'push "dhcp-option DNS 129.250.35.251"' >> /etc/openvpn/server.conf | |
| ;; | |
| 5) | |
| echo 'push "dhcp-option DNS 74.82.42.42"' >> /etc/openvpn/server.conf | |
| ;; | |
| 6) | |
| echo 'push "dhcp-option DNS 64.6.64.6"' >> /etc/openvpn/server.conf | |
| echo 'push "dhcp-option DNS 64.6.65.6"' >> /etc/openvpn/server.conf | |
| ;; | |
| esac | |
| echo "keepalive 10 120 | |
| cipher AES-256-CBC | |
| comp-lzo | |
| user nobody | |
| group $GROUPNAME | |
| persist-key | |
| persist-tun | |
| status openvpn-status.log | |
| verb 3 | |
| crl-verify crl.pem" >> /etc/openvpn/server.conf | |
| # Enable net.ipv4.ip_forward for the system | |
| sed -i '/\<net.ipv4.ip_forward\>/c\net.ipv4.ip_forward=1' /etc/sysctl.conf | |
| if ! grep -q "\<net.ipv4.ip_forward\>" /etc/sysctl.conf; then | |
| echo 'net.ipv4.ip_forward=1' >> /etc/sysctl.conf | |
| fi | |
| # Avoid an unneeded reboot | |
| echo 1 > /proc/sys/net/ipv4/ip_forward | |
| if pgrep firewalld; then | |
| # Using both permanent and not permanent rules to avoid a firewalld | |
| # reload. | |
| # We don't use --add-service=openvpn because that would only work with | |
| # the default port and protocol. | |
| firewall-cmd --zone=public --add-port=$PORT/$PROTOCOL | |
| firewall-cmd --zone=trusted --add-source=10.8.0.0/24 | |
| firewall-cmd --permanent --zone=public --add-port=$PORT/$PROTOCOL | |
| firewall-cmd --permanent --zone=trusted --add-source=10.8.0.0/24 | |
| # Set NAT for the VPN subnet | |
| firewall-cmd --direct --add-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP | |
| firewall-cmd --permanent --direct --add-rule ipv4 nat POSTROUTING 0 -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP | |
| else | |
| # Needed to use rc.local with some systemd distros | |
| if [[ "$OS" = 'debian' && ! -e $RCLOCAL ]]; then | |
| echo '#!/bin/sh -e | |
| exit 0' > $RCLOCAL | |
| fi | |
| chmod +x $RCLOCAL | |
| # Set NAT for the VPN subnet | |
| iptables -t nat -A POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP | |
| sed -i "1 a\iptables -t nat -A POSTROUTING -s 10.8.0.0/24 ! -d 10.8.0.0/24 -j SNAT --to $IP" $RCLOCAL | |
| 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. | |
| iptables -I INPUT -p $PROTOCOL --dport $PORT -j ACCEPT | |
| iptables -I FORWARD -s 10.8.0.0/24 -j ACCEPT | |
| iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT | |
| sed -i "1 a\iptables -I INPUT -p $PROTOCOL --dport $PORT -j ACCEPT" $RCLOCAL | |
| sed -i "1 a\iptables -I FORWARD -s 10.8.0.0/24 -j ACCEPT" $RCLOCAL | |
| sed -i "1 a\iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT" $RCLOCAL | |
| fi | |
| fi | |
| # If SELinux is enabled and a custom port or TCP was selected, we need this | |
| if hash sestatus 2>/dev/null; then | |
| if sestatus | grep "Current mode" | grep -qs "enforcing"; then | |
| if [[ "$PORT" != '1194' || "$PROTOCOL" = 'tcp' ]]; then | |
| # semanage isn't available in CentOS 6 by default | |
| if ! hash semanage 2>/dev/null; then | |
| yum install policycoreutils-python -y | |
| fi | |
| semanage port -a -t openvpn_port_t -p $PROTOCOL $PORT | |
| fi | |
| fi | |
| fi | |
| # And finally, restart OpenVPN | |
| if [[ "$OS" = 'debian' ]]; then | |
| # Little hack to check for systemd | |
| if pgrep systemd-journal; then | |
| systemctl restart openvpn@server.service | |
| else | |
| /etc/init.d/openvpn restart | |
| fi | |
| else | |
| if pgrep systemd-journal; then | |
| systemctl restart openvpn@server.service | |
| systemctl enable openvpn@server.service | |
| else | |
| service openvpn restart | |
| chkconfig openvpn on | |
| fi | |
| fi | |
| # Try to detect a NATed connection and ask about it to potential LowEndSpirit users | |
| EXTERNALIP=$(wget -4qO- "http://whatismyip.akamai.com/") | |
| if [[ "$IP" != "$EXTERNALIP" ]]; then | |
| echo "" | |
| echo "Looks like your server is behind a NAT!" | |
| echo "" | |
| echo "If your server is NATed (e.g. LowEndSpirit), I need to know the external IP" | |
| echo "If that's not the case, just ignore this and leave the next field blank" | |
| read -p "External IP: " -e USEREXTERNALIP | |
| if [[ "$USEREXTERNALIP" != "" ]]; then | |
| IP=$USEREXTERNALIP | |
| fi | |
| fi | |
| # client-common.txt is created so we have a template to add further users later | |
| echo "client | |
| dev tun | |
| proto $PROTOCOL | |
| sndbuf 0 | |
| rcvbuf 0 | |
| remote $IP $PORT | |
| resolv-retry infinite | |
| nobind | |
| persist-key | |
| persist-tun | |
| remote-cert-tls server | |
| auth SHA512 | |
| cipher AES-256-CBC | |
| comp-lzo | |
| setenv opt block-outside-dns | |
| key-direction 1 | |
| verb 3" > /etc/openvpn/client-common.txt | |
| # Generates the custom client.ovpn | |
| newclient "$CLIENT" | |
| echo "" | |
| echo "Finished!" | |
| echo "" | |
| echo "Your client configuration is available at" ~/"$CLIENT.ovpn" | |
| echo "If you want to add more clients, you simply need to run this script again!" | |
| fi |