feat: repell some pests

pests-repellent/src/index.ts

@@ -0,0 +1,31 @@
+export default {
+	async fetch(request, env, ctx): Promise<Response> {
+		const url = new URL(request.url);
+		const referer = request.headers.get('referer') || '';
+		const secFetchSite = request.headers.get('sec-fetch-site') || '';
+
+		// TODO: make this
+
+		// const knownFakeDomains = ["fakesite.example", "evilframe.net"]
+		// const isSuspicious = knownFakeDomains.some(domain => referer.includes(domain))
+		//
+		if (
+			// isSuspicious ||
+			secFetchSite === 'cross-site'
+		) {
+			return Response.redirect('https://fmhy.net', 302);
+		}
+
+		const res = await fetch(request);
+
+		const modifiedHeaders = new Headers(res.headers);
+		modifiedHeaders.set('X-Frame-Options', 'DENY');
+		modifiedHeaders.set('Content-Security-Policy', "frame-ancestors 'none'");
+
+		return new Response(res.body, {
+			status: res.status,
+			statusText: res.statusText,
+			headers: modifiedHeaders,
+		});
+	},
+} satisfies ExportedHandler<Env>;