Cloudflare DDNS Updater

update-cloudflare-dns.sh

#!/bin/bash
# Cloudflare Dynamic DNS Updater with Proxy
# Creates and updates DNS records to point to current public IP
# Handles wildcard, root domain, and specific subdomains

# Configuration
CLOUDFLARE_API_TOKEN="API_TOKEN"
ZONE_ID="ZONE_ID_TOKEN"
DOMAIN="domaingoeshere.com"

# Domains to create/manage
# Format: "domain_name:should_be_proxied (boolean)"
DOMAINS=(
    "example.com:true"              # Root domain - proxied
    "*.example.com:true"            # Wildcard - proxied
    "minecraft.example.com:false"   # Minecraft - NOT proxied (raw TCP)
    "zomboid.example.com:false"     # Zomboid - NOT proxied (raw TCP)
)

RECORD_TYPE="A"
TTL=1  # Auto TTL (Cloudflare decides)
LOG_FILE="/var/log/cloudflare-dns-update.log"

log_message() {
    echo "$(date '+%Y-%m-%d %H:%M:%S') - $1" | tee -a "$LOG_FILE"
}

get_public_ip() {
    local ip
    
    ip=$(curl -s --max-time 10 ifconfig.me || \
         curl -s --max-time 10 icanhazip.com || \
         curl -s --max-time 10 checkip.amazonaws.com)
    
    if [[ $ip =~ ^[0-9]+\.[0-9]+\.[0-9]+\.[0-9]+$ ]]; then
        echo "$ip"
    else
        return 1
    fi
}

get_dns_record_by_name() {
    local record_name="$1"
    log_message "Checking if record exists: $record_name"
    
    response=$(curl -s -X GET "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records?type=$RECORD_TYPE&name=$record_name" \
        -H "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
        -H "Content-Type: application/json")
    
    echo "$response"
}

create_dns_record() {
    local record_name="$1"
    local ip="$2"
    local proxied="$3"
    
    log_message "Creating new DNS record: $record_name -> $ip (proxied: $proxied)"
    
    response=$(curl -s -X POST "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records" \
        -H "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
        -H "Content-Type: application/json" \
        --data "{\"type\":\"$RECORD_TYPE\",\"name\":\"$record_name\",\"content\":\"$ip\",\"ttl\":$TTL,\"proxied\":$proxied}")
    
    if echo "$response" | grep -q '"success":true'; then
        log_message "✓ SUCCESS: Created $record_name"
        return 0
    else
        log_message "✗ FAILED: Could not create $record_name"
        log_message "Response: $response"
        return 1
    fi
}

update_dns_record() {
    local record_id="$1"
    local record_name="$2"
    local new_ip="$3"
    local proxied="$4"
    
    log_message "Updating DNS record: $record_name (ID: $record_id) -> $new_ip (proxied: $proxied)"
    
    response=$(curl -s -X PUT "https://api.cloudflare.com/client/v4/zones/$ZONE_ID/dns_records/$record_id" \
        -H "Authorization: Bearer $CLOUDFLARE_API_TOKEN" \
        -H "Content-Type: application/json" \
        --data "{\"type\":\"$RECORD_TYPE\",\"name\":\"$record_name\",\"content\":\"$new_ip\",\"ttl\":$TTL,\"proxied\":$proxied}")
    
    if echo "$response" | grep -q '"success":true'; then
        log_message "✓ SUCCESS: Updated $record_name"
        return 0
    else
        log_message "✗ FAILED: Could not update $record_name"
        log_message "Response: $response"
        return 1
    fi
}

process_domain() {
    local domain_entry="$1"
    local current_ip="$2"
    
    # Parse domain:proxied format
    local record_name="${domain_entry%:*}"
    local should_proxy="${domain_entry#*:}"
    
    log_message "=========================================="
    log_message "Processing: $record_name"
    log_message "Should be proxied: $should_proxy"
    
    # Check if record exists
    check_response=$(get_dns_record_by_name "$record_name")
    
    if ! echo "$check_response" | grep -q '"success":true'; then
        log_message "ERROR: Failed to check record existence"
        log_message "Response: $check_response"
        return 1
    fi
    
    # Check if we got any results
    result_count=$(echo "$check_response" | grep -o '"id":"[^"]*"' | wc -l)
    
    if [[ $result_count -eq 0 ]]; then
        log_message "Record does not exist, creating it..."
        create_dns_record "$record_name" "$current_ip" "$should_proxy"
    else
        log_message "Record exists, checking if update needed..."
        
        # Extract current record details
        record_id=$(echo "$check_response" | grep -o '"id":"[^"]*"' | head -1 | cut -d'"' -f4)
        record_ip=$(echo "$check_response" | grep -o '"content":"[^"]*"' | head -1 | cut -d'"' -f4)
        record_proxied=$(echo "$check_response" | grep -o '"proxied":[^,}]*' | head -1 | cut -d':' -f2 | tr -d ' ')
        
        log_message "Current values: IP=$record_ip, Proxied=$record_proxied"
        log_message "Desired values: IP=$current_ip, Proxied=$should_proxy"
        
        # Check if update needed
        if [[ "$record_ip" != "$current_ip" ]] || [[ "$record_proxied" != "$should_proxy" ]]; then
            log_message "Update required!"
            update_dns_record "$record_id" "$record_name" "$current_ip" "$should_proxy"
        else
            log_message "✓ No update needed - record is already correct"
        fi
    fi
}

main() {
    log_message "=========================================="
    log_message "Cloudflare DNS Manager - Create/Update"
    log_message "=========================================="
    
    # Ensure log file exists
    touch "$LOG_FILE" 2>/dev/null || {
        echo "ERROR: Cannot create log file $LOG_FILE"
        exit 1
    }
    
    log_message "Configuration:"
    log_message "  Domain: $DOMAIN"
    log_message "  Zone ID: $ZONE_ID"
    log_message "  Managing ${#DOMAINS[@]} DNS records"
    
    # Get current public IP
    log_message "Getting current public IP..."
    current_ip=$(get_public_ip)
    if [[ -z "$current_ip" ]]; then
        log_message "FATAL ERROR: Failed to get public IP"
        exit 1
    fi
    
    log_message "Current public IP: $current_ip"
    log_message ""
    
    # Process each domain
    success_count=0
    fail_count=0
    
    for domain_entry in "${DOMAINS[@]}"; do
        if process_domain "$domain_entry" "$current_ip"; then
            success_count=$((success_count + 1))
        else
            fail_count=$((fail_count + 1))
        fi
    done
    
    log_message "=========================================="
    log_message "Summary:"
    log_message "  Successful: $success_count"
    log_message "  Failed: $fail_count"
    log_message "  Total: ${#DOMAINS[@]}"
    log_message "=========================================="
    
    if [[ $fail_count -gt 0 ]]; then
        exit 1
    fi
}

main "$@"