OpenVPN client connect and disconnect notification to Discord (working on AsusWRT)

Readme.md

Discord notification for OpenVPN Client connect and Disconnect + GeoIP lookup

• simple: easy to understand code, just a text notification
• advanced: discord embeds with fields + GeoIP country and city lookup

client-connect-advanced.sh

#!/bin/sh

# Note: In AsusWRT you cannot use bash but just sh

# --- Configuration ---
# Add your Discord Webhook URL here
discord_url="https://discord.com/api/webhooks/your-webhook"
# Add your ipify API key here
api_key="abc123"
# Server name for the notification
server=$(hostname)
server_name="Unknown"

# Blacklisted users (space-separated)
# In case you have some client that you don't want to see notifications of then you can disable it for those users here
# blacklist="item1 item2 item3"
blacklist="baduser "
# Custom avatar URL for the webhook
# Default is OpenVPN logo
avatar_url="https://avatars.githubusercontent.com/u/1569141?s=200&v=4"

# --- Script variables. Set by asuswrt but can override for debugging ---
# script_type="client-connect"
# common_name="user"
# trusted_ip="8.8.8.8"

# --- Functions ---

# Translate server names into nice names
case "$server" in
"home")
  server_name="Home"
  ;;
"office")
  server_name="Office"
  ;;
esac

# Function to get city and country from IP using ipify.org
get_location() {
  echo "Fetching location for IP: $1" >&2
  local ip=$1
  local ipify_api=$(curl -s "https://geo.ipify.org/api/v2/country,city?apiKey=$api_key&ipAddress=$ip")
  city=$(echo "$ipify_api" | jq -r '.location.city // empty')
  country=$(echo "$ipify_api" | jq -r '.location.country // empty')
  echo "$city,$country"
}

# Function to generate the JSON payload for Discord
generate_post_data() {
  echo "Generating JSON..." >&2
  for item in $blacklist; do
    if [ "$item" = "$common_name" ]; then
      echo "User '$common_name' is in the blacklist. Aborting." >&2
      return 1
    fi
  done

  # Get location info for client IP
  location=$(get_location "$trusted_ip")
  city=$(echo "$location" | cut -d',' -f1)
  country=$(echo "$location" | cut -d',' -f2)

  if [ "$script_type" = "client-connect" ]; then
    title="User Connected"
    color=65280 # Green
  elif [ "$script_type" = "client-disconnect" ]; then
    title="User Disconnected"
    color=16711680 # Red
  fi

  # Construct the JSON payload with embeds
  cat <<EOF
{
  "username": "VPN",
  "avatar_url": "$avatar_url",
  "embeds": [{
    "title": "$server : $title",
    "description": "$description",
    "color": $color,
    "fields": [
      {
        "name": "User",
        "value": "${common_name:-Unknown}",
        "inline": true
      },
      {
        "name": "IP Address",
        "value": "$trusted_ip",
        "inline": true
      },
      {
        "name": "", 
        "value": "",
        "inline": true
      },
      {
        "name": "City",
        "value": "${city:-Unknown}",
        "inline": true
      },
      {
        "name": "Country",
        "value": "${country:-Unknown}",
        "inline": true
      }
    ]
  }]
}
EOF
}

# --- Main execution ---

# Generate JSON data
data=$(generate_post_data)

if [ $? -ne 0 ]; then
  echo "Could not generate data. Exiting." >&2
  exit 1
fi

# Send notification to Discord Webhook
echo "Sending notification to Discord..."
response=$(curl -s -o /dev/null -w "%{http_code}" -H "Content-Type: application/json" -X POST -d "$data" "$discord_url")

if [ "$response" -ge 200 ] && [ "$response" -lt 300 ]; then
  echo "Notification sent successfully."
else
  echo "Failed to send notification. HTTP status code: $response" >&2
  echo "Response data: $data" >&2
fi

client-connect-simple.sh

#!/bin/sh

# Note: In AsusWRT you cannot use bash but just sh

discord_url="https://discord.com/api/webhooks/your-webhook"

# Manually set variables for testing
# script_type="client-connect"
# common_name="someuser"

# space seperated list as string
# In case you have some client that you don't want to see notifications of then you can disable it for this user here
# blacklist="item1 item2 item3"
blacklist="baduser"

generate_post_data() {
    for item in $blacklist; do
      if [ "$item" = "$common_name" ]; then
        echo "User '$common_name' is in the blacklist. Skipping notification." >&2
        return 0
      fi
    done
    
    if [ "$script_type" = "client-connect" ]; then
        echo "{\"content\": \"User $common_name connected with IP $trusted_ip\"}"
    elif [ "$script_type" = "client-disconnect" ]; then
        echo "{\"content\": \"User $common_name disconnected with IP $trusted_ip\"}"
    fi
}

# Generate JSON data
data=$(generate_post_data)

if [ -z "$data" ]; then
    echo "No data to send. Exiting." >&2
    exit 1
fi

# Send notification to Discord Webhook
echo "Sending notification to Discord..."
response=$(curl -s -o /dev/null -w "%{http_code}" -H "Content-Type: application/json" -X POST -d "$data" "$discord_url")

if [ "$response" -eq 204 ]; then
    echo "Notification sent successfully."
else
    echo "Failed to send notification. HTTP status code: $response" >&2
fi

server.conf

status /var/log/openvpn-status.log # in case you want a simple way to view connected clients
status-version 1
script-security 2
client-connect /jffs/scripts/client-connect.sh # I use same script for both
client-disconnect /jffs/scripts/client-connect.sh
username-as-common-name # In some systems the $common_name variable is just 'user', this fixes it