Initial commit

background.js

@@ -0,0 +1,69 @@
+let blockingEnabled = true;
+
+chrome.runtime.onMessage.addListener((message, sender, sendResponse) => {
+  if (message.action === 'toggleBlocking') {
+    blockingEnabled = message.enabled;
+  }
+
+  if (message.action === 'getBlockingState') {
+    sendResponse({ action: 'setBlockingState', enabled: blockingEnabled });
+  }
+});
+
+chrome.webRequest.onHeadersReceived.addListener(
+  function(details) {
+    if (!blockingEnabled) {
+      return { cancel: false };
+    }
+    
+    // These are Cloudflare's headers, taken from here:
+    // https://developers.cloudflare.com/fundamentals/reference/http-headers/
+    const cloudflare_headers = [
+      'cf-connecting-ip',
+      'cf-connecting-ipv6',
+      'cf-ew-via',
+      'cf-Pseudo-ipv4',
+      'cf-ray',
+      'cf-ipcountry',
+      'cf-visitor',
+      'cf-worker'
+    ];
+    // You might want capture all headers prefixed with "cf-":
+    // const cf_header = details.responseHeaders.find(header =>
+    //   header.name.toLowerCase().startsWith('cf-')
+    // );
+    
+    const cf_header = details.responseHeaders.find(header =>
+      cloudflare_headers.includes(header.name.toLowerCase())
+    );
+
+    if (cf_header) {
+      console.log('Cloudflare header found:', cf_header);
+      
+      const query_params = new URLSearchParams({
+        name: cf_header.name,
+        value: cf_header.value,
+        url: details.url
+      }).toString();
+
+      /*
+       * It would be cool to pass the tab URL in the query params, but how?
+       * When accessing chrome.tabs here, the active tab URL is "about:newtab".
+       * Because we block the request immediately and the tab URL state doesn't
+       * never update to the URL we tried to access. I'd like to pass the URL
+       * to the web.archive.org/tab_url_here in blocked.html.
+       * Email contact@libroot.org if you know a solution!
+       */
+
+      // Redirect to our custom blocked.html page
+      const url = chrome.runtime.getURL('blocked.html') + '?' + query_params;
+      console.log('Redirecting to blocked page:', url);
+      chrome.tabs.update(details.tabId, { url: url });
+
+      // Block the request, reject Cloudflare!
+      return { cancel: true };
+    }
+  },
+  { urls: ['<all_urls>'] },
+  ['blocking', 'responseHeaders']
+);