# :icon-globe: ArcArcGo: DuckDuckGo Proxy with Custom Branding ![Cloudflare Workers](https://img.shields.io/badge/Cloudflare_Workers-F38020?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=cloudflare&logoColor=white) ![JavaScript](https://img.shields.io/badge/JavaScript-F7DF1E?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=javascript&logoColor=black) ![DuckDuckGo](https://img.shields.io/badge/DuckDuckGo-DE5833?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=duckduckgo&logoColor=white) ![License](https://img.shields.io/github/license/0xarchit/ArcArcGo?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=github&logoColor=white) ![Stars](https://img.shields.io/github/stars/0xarchit/ArcArcGo?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=github) ![Repo Size](https://img.shields.io/github/repo-size/0xarchit/ArcArcGo?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=github) ![Forks](https://img.shields.io/github/forks/0xarchit/ArcArcGo?style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=github) [![Website](https://img.shields.io/website?url=https://arcarcgo.0xarchit.is-a.dev/&style=for-the-badge&logoColor=white&labelColor=000000&color=000000&logo=html5)](https://arcarcgo.0xarchit.is-a.dev/){target="_blank"} :icon-mark-github: **GitHub**: [0xarchit/ArcArcGo](https://github.com/0xarchit/ArcArcGo){target="_blank"} :icon-globe: **Live Demo**: [https://arcarcgo.0xarchit.is-a.dev](https://arcarcgo.0xarchit.is-a.dev/){target="_blank"} > [!TIP] > ArcArcGo is a Cloudflare Worker that acts as a transparent proxy for DuckDuckGo, implementing custom branding and URL rewriting through regex patterns and JavaScript injection. ## :icon-device-desktop: Screenshot ![ArcArcGo Interface](Public/ArcArcGo/image.png) ## :icon-info: Overview ArcArcGo demonstrates advanced Cloudflare Workers capabilities by intercepting requests, fetching content from DuckDuckGo, and modifying responses before serving them to clients with custom branding and functionality. --- ## :icon-workflow: Architecture ### Request Flow 1. **Client Request** → Cloudflare Worker 2. **Worker Processing** → DuckDuckGo Server 3. **Response Modification** → Client ```mermaid graph LR A[Client] --> B[Cloudflare Worker] B --> C[DuckDuckGo] C --> B B --> A B -.-> D[URL Rewriting + Branding] ``` --- ## :icon-tools: Core Components ### :icon-play: 1. Event Listener The worker uses a fetch event listener to intercept all incoming HTTP requests and delegates processing to the main `handleRequest` function. ### :icon-gear: 2. Request Handler (`handleRequest`) #### :icon-link: URL Construction The worker extracts the pathname, search parameters, and hash from incoming requests and constructs the target DuckDuckGo URL while maintaining the original query structure. #### :icon-package: Header Processing **Header Modifications:** - **Removed:** `Host`, `X-Forwarded-For` (prevents detection as proxy) - **Set:** Standard browser `Accept` header - **Set:** Default `User-Agent` if not present #### :icon-sync: Response Processing **Response Header Modifications:** - **Removed:** `Content-Security-Policy` (allows script injection) - **Added:** CORS header for cross-origin access ### :icon-file-code: 3. Content Type Handling #### :icon-image: Non-HTML Content Images, CSS, JavaScript, and other assets are passed through unchanged, maintaining original response body and headers. #### :icon-code: HTML Content Processing Uses `TransformStream` for real-time content modification without buffering the entire response. --- ## :icon-link-external: URL Rewriting System ### :icon-search: Pattern Matching The worker uses comprehensive regex patterns to identify and rewrite URLs, including: - **Standard HTML attributes:** `href`, `src`, `action` in both double and single quotes - **CSS URLs:** `url()` declarations - **Meta refresh:** URL redirects in meta tags - **JavaScript redirects:** `window.location`, `location.href`, etc. - **Data attributes:** Custom data URLs for navigation - **Absolute paths:** Standalone paths in quotes - **Event handlers:** `onclick`, `onchange`, `onsubmit` attributes ### :icon-arrow-switch: URL Transformation Logic #### :icon-globe: 1. Absolute URLs Only processes DuckDuckGo URLs by stripping the domain and prepending the proxy base URL. #### :icon-file-directory: 2. Relative URLs Resolves relative URLs against the DuckDuckGo origin while maintaining query parameters. #### :icon-alert: 3. Special Cases - **Fragments (#):** Preserved unchanged - **Data URLs:** Preserved unchanged - **JavaScript URLs:** Preserved unchanged - **Event Handlers:** Special processing for location changes --- ## :icon-paintbrush: Branding System ### :icon-pencil: Text Replacement Real-time text replacement in HTML content using regex patterns to replace "DuckDuckGo" with "ArcArcGo" and handle possessive forms. ### :icon-image: Logo Replacement Regex-based logo replacement that identifies DuckDuckGo logo images and replaces them with the custom ArcArcGo logo. ### :icon-code: JavaScript Injection Dynamic branding through injected script that: - **Text Replacement:** Uses TreeWalker to traverse all text nodes - **Title Replacement:** Updates document title - **Logo Replacement:** Targets specific CSS selectors for logo images - **Dynamic Monitoring:** Uses MutationObserver for continuously added content - **Multiple Triggers:** Responds to load, DOMContentLoaded events, and periodic intervals --- ## :icon-workflow: Stream Processing ### :icon-package: Chunked Processing The worker processes content in chunks to optimize memory usage and provide real-time response modification. It uses a buffer system with: **Buffer Management:** - **Size Threshold:** 8192 bytes - **Content Threshold:** Presence of `` tag - **Final Processing:** Script injection before response completion --- ## :icon-alert: Error Handling The worker implements comprehensive error handling for: - Network connectivity issues - Invalid URL construction - Stream processing errors - Regex processing failures All errors return a 500 status response with a descriptive error message. --- ## :icon-zap: Performance Considerations ### :icon-rocket: Optimization Strategies 1. **Selective Processing:** Only HTML content is modified 2. **Chunked Streaming:** Real-time processing without buffering entire response 3. **Efficient Regex:** Compiled patterns for fast matching 4. **Header Optimization:** Minimal header modifications ### :icon-graph: Resource Usage - **Memory:** Stream-based processing minimizes memory usage - **CPU:** Regex operations on text chunks - **Network:** Direct proxy with minimal latency --- ## :icon-shield: Security Considerations ### :icon-check: Mitigations Implemented 1. **CSP Removal:** Enables script injection 2. **Header Sanitization:** Removes tracking headers 3. **URL Validation:** Prevents open proxy attacks 4. **Content Filtering:** Only processes specific content types ### :icon-alert: Potential Risks - **Open Proxy:** Limited to DuckDuckGo domain - **Script Injection:** Controlled injection for branding only - **Privacy:** No logging or data collection --- ## :icon-rocket: Deployment Guide ### :icon-checklist: Prerequisites - Cloudflare account - Workers subscription (free tier available) ### :icon-upload: Deployment Steps 1. **Create Worker:** In Cloudflare dashboard 2. **Deploy Code:** Copy `worker.js` content 3. **Configure Routes:** Set custom domain or use workers.dev subdomain 4. **Test Functionality:** Verify search and branding ### :icon-gear: Configuration Options - **Custom Logo:** Modify `newLogoSrc` variable - **Branding Text:** Adjust replacement patterns - **Target Domain:** Change `targetHost` for different proxy targets --- ## :icon-tools: Troubleshooting ### :icon-bug: Common Issues #### :icon-code: 1. Script Injection Not Working - **Cause:** CSP blocking or timing issues - **Solution:** Verify CSP removal, check MutationObserver #### :icon-link: 2. URLs Not Rewriting - **Cause:** Pattern mismatch or encoding issues - **Solution:** Test regex patterns, check URL encoding #### :icon-zap: 3. Performance Issues - **Cause:** Large content or complex patterns - **Solution:** Optimize buffer size, simplify regex patterns ### :icon-bug: Debug Techniques 1. **Console Logging:** Add logging to worker (remove in production) 2. **Network Inspection:** Check headers and response codes 3. **Content Validation:** Verify HTML modifications --- ## :icon-stop: Limitations ### :icon-cpu: Technical Limitations - **JavaScript-Heavy Sites:** May require additional pattern matching - **Dynamic Content:** MutationObserver helps but may miss rapid changes - **Complex URLs:** Some edge cases may not be covered ### :icon-law: Legal Considerations - **Terms of Service:** May violate target site's ToS - **Copyright:** Logo and content modifications - **Educational Use:** Intended for learning purposes only --- > [!WARNING] > **Important Notice**: This is not a clone or phishing page. This is an educational project created while exploring Cloudflare Workers and can be treated as a prototype for creating similar website proxies. It will be removed if it violates any ToS or is found to be illegal. > > **Contact**: mail@0xarchit.is-a.dev --- ## :icon-trophy: Conclusion ArcArcGo demonstrates advanced Cloudflare Workers capabilities including: +++ :icon-gear: Technical Features - Real-time content transformation - Complex regex-based URL rewriting - Dynamic JavaScript injection - Stream processing optimization +++ :icon-rocket: Implementation Highlights - Practical proxy server development - Performance optimization techniques - Maintaining functionality of underlying service - Educational exploration of web proxy concepts +++ The implementation showcases how modern edge computing can be used to create sophisticated web proxies while maintaining the performance and functionality of the underlying service.