Cloudflare DDNS

About

This script is used to update Dynamic DNS (DDNS) service based on Cloudflare! Access your home network remotely via a custom domain name without a static IP!

• DDNS Cloudflare Bash Script for most Linux distributions.
• Cloudflare's options configurable.
• Discord, Telegram and Email Notifications

Requirements:

• A Cloudflare account and a domain for which you want to set up DDNS.
• An API key from Cloudflare.
• curl and jq installed on your Linux system (for making API requests and parsing JSON responses).

Important Notes:

1. Security: Never share your API keys, tokens, or other sensitive data. Be careful not to place them in publicly accessible locations.
2. Dependencies: Ensure you have curl and jq installed, as well as a configured and working mail system (sendmail, postfix, etc.) on your server.
3. Testing: Before deploying and automating, thoroughly test the script to ensure that all components are working correctly.

Here are two ways to authenticate requests to the Cloudflare API:

Using the Global API Key:

If you use the Global API Key, you need to include two headers in the request: X-Auth-Email and X-Auth-Key. Ensure you provide the correct email address associated with your Cloudflare account and your Global API Key.

curl -X GET "https://api.cloudflare.com/client/v4/zones/YOUR_ZONE_ID/dns_records" -H "X-Auth-Email: YOUR_EMAIL" -H "X-Auth-Key: YOUR_GLOBAL_API_KEY" -H "Content-Type: application/json"

Using an API Token:

If you decide to use an API token, you will need only one header: Authorization, to which you will attach the API token preceded by the word Bearer.

curl -X GET "https://api.cloudflare.com/client/v4/zones/YOUR_ZONE_ID/dns_records" -H "Authorization: Bearer YOUR_API_TOKEN" -H "Content-Type: application/json"

In both cases, replace YOUR_ZONE_ID, YOUR_EMAIL, YOUR_GLOBAL_API_KEY, or YOUR_API_TOKEN with the appropriate values for your account and domain.

Diagnostics and Troubleshooting:

• Ensure you are using correct data: Check if the email address and API key are correct and belong to the account holder of Cloudflare you are trying to use.
• Check the validity of the API token: If using an API token, ensure it has the necessary permissions to perform operations on DNS records.
• Use the correct headers: According to the error message, ensure that your request uses either X-Auth-Email and X-Auth-Key headers, or the Authorization header with a correct API token.
• Check for typos: Ensure there are no typos or extra spaces in the headers that could disrupt the authorization process.

Usage

Step 1: Obtain a Cloudflare API Key

1. Log in to your Cloudflare account.
2. Go to the “My Profile” section.
3. Find the “API Tokens” section and generate a new token with the appropriate permissions, or use your Global API Key.

Step 2: Find Zone ID and Record ID

To update a DNS record, you need the Zone ID of your domain and the Record ID of the record you want to update.

1. Finding Zone ID:

   • You can find the Zone ID in the Cloudflare dashboard for your domain, in the “Overview” section.

2. Finding Record ID:

   • Use the following command, replacing YOUR_ZONE_ID, YOUR_EMAIL, and YOUR_API_KEY with your values.

   curl -X GET "https://api.cloudflare.com/client/v4/zones/YOUR_ZONE_ID/dns_records" -H "Authorization: Bearer YOUR_API_KEY" -H "Content-Type: application/json"

   • Review the response to find the ID of the record you want to update.

Step 3: DDNS Update Script

Before running, configure the cloudflare_ddns.sh script according to your personal requirements.

Configuration

Cloudflare API

# Cloudflare API configuration
CF_ZONE_ID="YOUR_ZONE_ID"
CF_RECORD_ID="YOUR_RECORD_ID"
CF_API_KEY="YOUR_API_TOKEN"
CF_EMAIL="YOUR_EMAIL"
CF_DOMAIN="example.com"
PUBLIC_IP=$(curl -s http://ipv4.icanhazip.com)

# DNS record configuration set by the user
CF_DNS_TTL=1                 # TTL value, set by user, default to 1 (auto)
CF_DNS_PROXIED=true        # Set true to proxy through Cloudflare, false to disable

Notifications

# Webhooks and Email configuration
DISCORD_WEBHOOK_URL="YOUR_DISCORD_WEBHOOK_URL"
TELEGRAM_BOT_TOKEN="YOUR_TELEGRAM_BOT_TOKEN"
TELEGRAM_CHAT_ID="YOUR_TELEGRAM_CHAT_ID"
SLACK_WEBHOOK_URL="YOUR_SLACK_WEBHOOK_URL"
EMAIL_RECIPIENT="YOUR_EMAIL_RECIPIENT"
EMAIL_SUBJECT="DDNS Update Notification"

# User notification preferences
NOTIFICATION_ENABLE_DISCORD=false    	# Set to false to disable Discord notifications
NOTIFICATION_ENABLE_TELEGRAM=false  	# Set to false to disable Telegram notifications
NOTIFICATION_ENABLE_SLACK=false     	# Set to false to disable Slack notifications
NOTIFICATION_ENABLE_EMAIL=false     	# Set to false to disable Email notifications
NOTIFICATION_SECURE_PUBLIC_IP=true  	# value true limits display of public ip in notifications,
					# value false displays old and new public ip address

# Log file configuration
LOG_FILE="/path/to/cloudflare_ddns_bifrost.log"  # Full path to logfile.
MAX_LOG_ENTRIES=288				 # Max Log Entries in LOG_FILE, 288=24h/5min

Step 4: Grant Execution Permissions and Run the Script

1. Grant execution permissions to the script: chmod +x cloudflare_ddns.sh
2. Run the script to update the DNS record: ./cloudflare_ddns.sh

Step 5: Automation with Cron

To have the script run automatically, you can add it to crontab:

1. Open crontab: crontab -e
2. Add a line to crontab to have the script run hourly (you can adjust the frequency):

@reboot /path/to/cloudflare_ddns.sh
*/5 * * * * /path/to/cloudflare_ddns.sh

# ┌───────────── minute (0 - 59)
# │ ┌───────────── hour (0 - 23)
# │ │ ┌───────────── day of the month (1 - 31)
# │ │ │ ┌───────────── month (1 - 12)
# │ │ │ │ ┌───────────── day of the week (0 - 6) (Sunday to Saturday 7 is also Sunday on some systems)
# │ │ │ │ │ ┌───────────── command to issue                               
# │ │ │ │ │ │
# │ │ │ │ │ │
# * * * * * /bin/bash {Location of the script}

Notifications

1. Discord Webhook

Create a Webhook on Discord:

• Go to your Discord server settings, select “Integrations”, and then “Webhooks”.

• Create a new webhook and copy its URL.

• Send a message using the webhook:

  • Use the following command, replacing WEBHOOK_URL with the webhook URL and YOUR_MESSAGE with your message.

  curl -H "Content-Type: application/json" -X POST -d '{"content":"YOUR_MESSAGE"}' WEBHOOK_URL

2. Telegram Bot

1. Create a Bot on Telegram:

   • Use BotFather on Telegram to create a new bot. You will receive an API token.

2. Send a message using the bot:

   • Find the chat_id by sending a message to the bot and visiting https://api.telegram.org/bot<TOKEN>/getUpdates.
   • Use the following command, replacing <TOKEN> with the bot’s token, <CHAT_ID> with the chat identifier, and YOUR_MESSAGE with your message.

   curl -X POST https://api.telegram.org/bot<TOKEN>/sendMessage -d chat_id=<CHAT_ID> -d text="YOUR_MESSAGE"

3. Email

To send emails, you can use the email program available on most Unix/Linux systems. However, you must have a mail client configured on your server (e.g. sendmail or postfix).

1. Send an email:
   • Use the following command, replacing RECIPIENT_EMAIL with the recipient's email address, SUBJECT with the subject of the message, and YOUR_MESSAGE with the content of the message. echo "YOUR_MESSAGE" | mail -s "SUBJECT" RECIPIENT_EMAIL