push code

README.md

@@ -0,0 +1,11 @@
+# AutoGRE 
+
+Tool to dynamically update GRE tunnels in a network based on a FQDN.
+
+## Installation
+
+Not good looking install command by curl and bash:
+
+```bash
+curl -s https://git.gnous.eu/mael/autogre/raw/branch/main/install.sh | bash
+```

autogre.sh

@@ -6,15 +6,13 @@
 # If not defined in the environment, the following variables will be used
 
 if [[ -z $GRE_TUNNEL_NAME ]]; then
-    GRE_TUNNEL_NAME="gre1"
     GRE_TUNNEL_NAME="gre1"
     GRE_LOCAL_IP="45.13.XX.XX"
     GRE_LAN_IP_4="192.168.100.1/24"
     GRE_LAN_IP_6="2a0e:fd45:2a0c::1/64"
+    FQDN="remote.example.com"
 fi
 
-FQDN=$1 # The remote host FQDN
-
 # FUNCTIONS
 function usage() {
     echo "Usage: $0 <remote_host_fqdn>"
@@ -28,14 +26,6 @@ function check_root() {
     fi
 }
 
-
-function check_fqdn() {
-    if [[ -z $FQDN ]]; then
-        echo "Please provide the remote host FQDN"
-        usage
-    fi
-}
-
 function get_current_ip() {
     # Get the dst IP on the GRE tunnel
     CURRENT_IP=$(ip addr show $GRE_TUNNEL_NAME | grep -Po 'peer \K[\d.]+')
@@ -98,7 +88,6 @@ function check_remote_ip() {
 # MAIN
 function main() {
     check_root
-    check_fqdn
 
     echo "LOG - $(date) - Starting autogre.sh"
     echo "LOG - $(date) - FQDN: $FQDN"

default.example

@@ -0,0 +1,8 @@
+# Default environment variables example
+# Copy in /etc/default/autogre - and edit
+
+GRE_TUNNEL_NAME="gre_ren"
+GRE_LOCAL_IP="10.10.10.10"
+GRE_LAN_IP_4="192.168.100.1/24"
+GRE_LAN_IP_6="2a0e:fd45:2a0e::/126"
+FQDN="example.infra.tech"

install.sh

@@ -0,0 +1,59 @@
+#!/bin/bash 
+
+# INSTALLATION SCRIPT FOR autogre.sh
+# Will install the script in /usr/local/bin/autogre.sh
+# Will install the systemd service in /etc/systemd/system/autogre.service
+# Will install the systemd timer in /etc/systemd/system/autogre.timer
+
+# FUNCTIONS
+
+function copy_auto_gre() {
+    curl https://git.gnous.eu/mael/autogre/raw/branch/main/autogre.sh > /usr/local/bin/autogre.sh
+    chmod +x /usr/local/bin/autogre.sh
+}
+
+function generate_systemd_service() {
+    cat << EOF > /etc/systemd/system/autogre.service
+[Unit]
+Description=Auto GRE tunnel service
+After=network.target
+
+[Service]
+EnvironmentFile=/etc/default/autogre
+Type=simple
+ExecStart=/usr/local/bin/autogre.sh
+
+[Install]
+WantedBy=multi-user.target
+EOF
+}
+
+function generate_systemd_timer() {
+    cat << EOF > /etc/systemd/system/autogre.timer
+[Unit]
+Description=Auto GRE tunnel timer
+
+[Timer]
+OnBootSec=1min
+OnUnitActiveSec=1min
+
+[Install]
+WantedBy=timers.target
+EOF
+}
+
+function enable_systemd_timer_and_service() {
+    systemctl enable autogre.service
+    systemctl start autogre.service
+    systemctl enable autogre.timer
+    systemctl start autogre.timer
+}
+
+function main() {
+    copy_auto_gre
+    generate_systemd_service
+    generate_systemd_timer
+    enable_systemd_timer_and_service
+}
+
+main