csrf token and browser detection

apps/web/src/app/api/waitlist/route.ts

@@ -4,51 +4,179 @@ import { waitlist } from "@opencut/db/schema";
 import { nanoid } from "nanoid";
 import { waitlistRateLimit } from "@/lib/rate-limit";
 import { z } from "zod";
+import { env } from "@/env";
+import { cookies } from "next/headers";
+import crypto from "crypto";
 
 const waitlistSchema = z.object({
   email: z.string().email("Invalid email format").min(1, "Email is required"),
 });
 
+const CSRF_TOKEN_NAME = "waitlist-csrf";
+const TOKEN_EXPIRY = 60 * 60 * 1000;
+
+function validateBrowserRequest(request: NextRequest): boolean {
+  const origin = request.headers.get("origin");
+  const referer = request.headers.get("referer");
+  const userAgent = request.headers.get("user-agent") || "";
+  const secFetchSite = request.headers.get("sec-fetch-site");
+  const secFetchMode = request.headers.get("sec-fetch-mode");
+  const secFetchDest = request.headers.get("sec-fetch-dest");
+  const contentType = request.headers.get("content-type");
+  const accept = request.headers.get("accept");
+
+  if (env.NODE_ENV === "development") {
+    console.log("=== Validating Browser Request ===");
+    console.log("Origin:", origin);
+    console.log("Referer:", referer);
+    console.log("User-Agent:", userAgent);
+    console.log("Sec-Fetch-Site:", secFetchSite);
+    console.log("Sec-Fetch-Mode:", secFetchMode);
+    console.log("Sec-Fetch-Dest:", secFetchDest);
+    console.log("Content-Type:", contentType);
+    console.log("Accept:", accept);
+  }
+
+  const allowedOrigins =
+    env.NODE_ENV === "development" ? ["http://localhost:3000", "http://127.0.0.1:3000"] : ["https://opencut.app", "https://www.opencut.app"];
+
+  if (!origin || !allowedOrigins.includes(origin)) {
+    console.log("Failed: Invalid origin");
+    return false;
+  }
+
+  if (!referer || !referer.startsWith(origin)) {
+    console.log("Failed: Invalid referer");
+    return false;
+  }
+
+  const suspiciousUserAgents = [
+    "curl",
+    "wget",
+    "postman",
+    "insomnia",
+    "thunder client",
+    "httpie",
+    "python-requests",
+    "node-fetch",
+    "axios",
+    "scrapy",
+    "httpclient",
+    "okhttp",
+    "libwww-perl",
+    "python-urllib",
+    "go-http-client",
+    "java/",
+    "apache-httpclient",
+  ];
+
+  const lowerUserAgent = userAgent.toLowerCase();
+  if (!userAgent || suspiciousUserAgents.some((agent) => lowerUserAgent.includes(agent))) {
+    console.log("Failed: Suspicious user agent");
+    return false;
+  }
+
+  const hasBrowserIndicators =
+    lowerUserAgent.includes("mozilla/") ||
+    lowerUserAgent.includes("chrome/") ||
+    lowerUserAgent.includes("safari/") ||
+    lowerUserAgent.includes("firefox/") ||
+    lowerUserAgent.includes("edge/");
+
+  if (!hasBrowserIndicators) {
+    console.log("Failed: No browser indicators in user agent");
+    return false;
+  }
+
+  if (secFetchSite && secFetchSite !== "same-origin") {
+    console.log("Failed: Invalid Sec-Fetch-Site:", secFetchSite);
+    return false;
+  }
+
+  if (secFetchMode && secFetchMode !== "cors") {
+    console.log("Failed: Invalid Sec-Fetch-Mode:", secFetchMode);
+    return false;
+  }
+
+  if (secFetchDest && secFetchDest !== "empty") {
+    console.log("Failed: Invalid Sec-Fetch-Dest:", secFetchDest);
+    return false;
+  }
+
+  if (!contentType || !contentType.includes("application/json")) {
+    console.log("Failed: Invalid Content-Type");
+    return false;
+  }
+
+  if (!accept || (!accept.includes("application/json") && !accept.includes("*/*"))) {
+    console.log("Failed: Invalid Accept header");
+    return false;
+  }
+
+  console.log("Browser validation passed!");
+  return true;
+}
+
+async function validateCSRFToken(request: NextRequest): Promise<boolean> {
+  const clientToken = request.headers.get("x-csrf-token");
+  if (!clientToken) return false;
+
+  const cookieStore = await cookies();
+  const cookieValue = cookieStore.get(CSRF_TOKEN_NAME)?.value;
+  if (!cookieValue) return false;
+
+  const [token, timestamp, signature] = cookieValue.split(":");
+  if (!token || !timestamp || !signature) return false;
+
+  if (clientToken !== token) return false;
+
+  const now = Date.now();
+  const tokenTime = parseInt(timestamp);
+  if (now - tokenTime > TOKEN_EXPIRY) return false;
+
+  const expectedSignature = crypto
+    .createHmac("sha256", env.BETTER_AUTH_SECRET || "fallback-secret")
+    .update(`${token}:${timestamp}`)
+    .digest("hex");
+
+  return signature === expectedSignature;
+}
+
 export async function POST(request: NextRequest) {
-  // Rate limit check
   const identifier = request.headers.get("x-forwarded-for") ?? "127.0.0.1";
   const { success } = await waitlistRateLimit.limit(identifier);
 
   if (!success) {
-    return NextResponse.json(
-      { error: "Too many requests. Please try again later." },
-      { status: 429 }
-    );
+    return NextResponse.json({ error: "Too many requests. Please try again later." }, { status: 429 });
+  }
+
+  if (!validateBrowserRequest(request)) {
+    await new Promise((resolve) => setTimeout(resolve, Math.random() * 2000 + 1000));
+
+    return NextResponse.json({ error: "Invalid request" }, { status: 403 });
+  }
+
+  const isValidToken = await validateCSRFToken(request);
+  if (!isValidToken) {
+    return NextResponse.json({ error: "Invalid security token" }, { status: 403 });
   }
 
   try {
     const body = await request.json();
     const { email } = waitlistSchema.parse(body);
 
-    // Check if email already exists
-    const existingEmail = await db
-      .select()
-      .from(waitlist)
-      .where(eq(waitlist.email, email.toLowerCase()))
-      .limit(1);
+    const existingEmail = await db.select().from(waitlist).where(eq(waitlist.email, email.toLowerCase())).limit(1);
 
     if (existingEmail.length > 0) {
-      return NextResponse.json(
-        { error: "Email already registered" },
-        { status: 409 }
-      );
+      return NextResponse.json({ error: "Email already registered" }, { status: 409 });
     }
 
-    // Add to waitlist
     await db.insert(waitlist).values({
       id: nanoid(),
       email: email.toLowerCase(),
     });
 
-    return NextResponse.json(
-      { message: "Successfully joined waitlist!" },
-      { status: 201 }
-    );
+    return NextResponse.json({ message: "Successfully joined waitlist!" }, { status: 201 });
   } catch (error) {
     if (error instanceof z.ZodError) {
       const firstError = error.errors[0];
@@ -56,9 +184,6 @@ export async function POST(request: NextRequest) {
     }
 
     console.error("Waitlist signup error:", error);
-    return NextResponse.json(
-      { error: "Internal server error" },
-      { status: 500 }
-    );
+    return NextResponse.json({ error: "Internal server error" }, { status: 500 });
   }
 }

apps/web/src/app/api/waitlist/token/route.ts

@@ -0,0 +1,47 @@
+import { NextRequest, NextResponse } from "next/server";
+import { cookies } from "next/headers";
+import crypto from "crypto";
+import { env } from "@/env";
+
+const CSRF_TOKEN_NAME = "waitlist-csrf";
+const TOKEN_EXPIRY = 60 * 60 * 1000;
+
+export async function GET(request: NextRequest) {
+  const referer = request.headers.get("referer");
+  const host = request.headers.get("host");
+
+  if (referer) {
+    const refererUrl = new URL(referer);
+    const allowedHosts = env.NODE_ENV === "development" ? ["localhost:3000", "127.0.0.1:3000"] : ["opencut.app", "www.opencut.app"];
+
+    if (!allowedHosts.some((allowed) => refererUrl.host === allowed || refererUrl.host.endsWith(allowed))) {
+      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+    }
+  } else if (host) {
+    const allowedHosts = env.NODE_ENV === "development" ? ["localhost:3000", "127.0.0.1:3000"] : ["opencut.app", "www.opencut.app"];
+
+    if (!allowedHosts.some((allowed) => host === allowed || host.endsWith(allowed))) {
+      return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+    }
+  } else {
+    return NextResponse.json({ error: "Forbidden" }, { status: 403 });
+  }
+
+  const token = crypto.randomBytes(32).toString("hex");
+  const timestamp = Date.now();
+  const signature = crypto
+    .createHmac("sha256", env.BETTER_AUTH_SECRET || "fallback-secret")
+    .update(`${token}:${timestamp}`)
+    .digest("hex");
+
+  const cookieStore = await cookies();
+  cookieStore.set(CSRF_TOKEN_NAME, `${token}:${timestamp}:${signature}`, {
+    httpOnly: true,
+    secure: env.NODE_ENV === "production",
+    sameSite: "strict",
+    maxAge: TOKEN_EXPIRY / 1000,
+    path: "/",
+  });
+
+  return NextResponse.json({ token });
+}

apps/web/src/components/landing/hero.tsx

@@ -4,7 +4,7 @@ import { motion } from "motion/react";
 import { Button } from "../ui/button";
 import { Input } from "../ui/input";
 import { ArrowRight } from "lucide-react";
-import { useState } from "react";
+import { useState, useEffect } from "react";
 import { toast } from "sonner";
 
 import Image from "next/image";
@@ -13,6 +13,20 @@ import { Handlebars } from "./handlebars";
 export function Hero() {
   const [email, setEmail] = useState("");
   const [isSubmitting, setIsSubmitting] = useState(false);
+  const [csrfToken, setCsrfToken] = useState<string | null>(null);
+
+  useEffect(() => {
+    fetch("/api/waitlist/token", {
+      credentials: "include",
+    })
+      .then((res) => res.json())
+      .then((data) => {
+        if (data.token) {
+          setCsrfToken(data.token);
+        }
+      })
+      .catch((err) => console.error("Failed to fetch CSRF token:", err));
+  }, []);
 
   const handleSubmit = async (e: React.FormEvent) => {
     e.preventDefault();
@@ -24,6 +38,13 @@ export function Hero() {
       return;
     }
 
+    if (!csrfToken) {
+      toast.error("Security error", {
+        description: "Please refresh the page and try again.",
+      });
+      return;
+    }
+
     setIsSubmitting(true);
 
     try {
@@ -31,7 +52,9 @@ export function Hero() {
         method: "POST",
         headers: {
           "Content-Type": "application/json",
+          "X-CSRF-Token": csrfToken,
         },
+        credentials: "include",
         body: JSON.stringify({ email: email.trim() }),
       });
 
@@ -42,11 +65,15 @@ export function Hero() {
           description: "You'll be notified when we launch.",
         });
         setEmail("");
+
+        fetch("/api/waitlist/token", { credentials: "include" })
+          .then((res) => res.json())
+          .then((data) => {
+            if (data.token) setCsrfToken(data.token);
+          });
       } else {
         toast.error("Oops!", {
-          description:
-            (data as { error: string }).error ||
-            "Something went wrong. Please try again.",
+          description: (data as { error: string }).error || "Something went wrong. Please try again.",
         });
       }
     } catch (error) {
@@ -60,13 +87,7 @@ export function Hero() {
 
   return (
     <div className="min-h-[calc(100vh-4.5rem)] supports-[height:100dvh]:min-h-[calc(100dvh-4.5rem)] flex flex-col justify-between items-center text-center px-4">
-      <Image
-        className="absolute top-0 left-0 -z-50 size-full object-cover"
-        src="/landing-page-bg.png"
-        height={1903.5}
-        width={1269}
-        alt="landing-page.bg"
-      />
+      <Image className="absolute top-0 left-0 -z-50 size-full object-cover" src="/landing-page-bg.png" height={1903.5} width={1269} alt="landing-page.bg" />
       <motion.div
         initial={{ opacity: 0 }}
         animate={{ opacity: 1 }}
@@ -89,20 +110,11 @@ export function Hero() {
           animate={{ opacity: 1 }}
           transition={{ delay: 0.4, duration: 0.8 }}
         >
-          A simple but powerful video editor that gets the job done. Works on
-          any platform.
+          A simple but powerful video editor that gets the job done. Works on any platform.
         </motion.p>
 
-        <motion.div
-          className="mt-12 flex gap-8 justify-center"
-          initial={{ opacity: 0 }}
-          animate={{ opacity: 1 }}
-          transition={{ delay: 0.6, duration: 0.8 }}
-        >
-          <form
-            onSubmit={handleSubmit}
-            className="flex gap-3 w-full max-w-lg flex-col sm:flex-row"
-          >
+        <motion.div className="mt-12 flex gap-8 justify-center" initial={{ opacity: 0 }} animate={{ opacity: 1 }} transition={{ delay: 0.6, duration: 0.8 }}>
+          <form onSubmit={handleSubmit} className="flex gap-3 w-full max-w-lg flex-col sm:flex-row">
             <div className="relative w-full">
               <Input
                 type="email"
@@ -110,19 +122,12 @@ export function Hero() {
                 className="h-11 text-base flex-1"
                 value={email}
                 onChange={(e) => setEmail(e.target.value)}
-                disabled={isSubmitting}
+                disabled={isSubmitting || !csrfToken}
                 required
               />
             </div>
-            <Button
-              type="submit"
-              size="lg"
-              className="px-6 h-11 text-base !bg-foreground"
-              disabled={isSubmitting}
-            >
-              <span className="relative z-10">
-                {isSubmitting ? "Joining..." : "Join waitlist"}
-              </span>
+            <Button type="submit" size="lg" className="px-6 h-11 text-base !bg-foreground" disabled={isSubmitting || !csrfToken}>
+              <span className="relative z-10">{isSubmitting ? "Joining..." : "Join waitlist"}</span>
               <ArrowRight className="relative z-10 ml-0.5 h-4 w-4 inline-block" />
             </Button>
           </form>

apps/web/src/lib/rate-limit.ts

@@ -12,4 +12,5 @@ export const waitlistRateLimit = new Ratelimit({
   redis,
   limiter: Ratelimit.slidingWindow(5, "1 m"), // 5 requests per minute
   analytics: true,
+  prefix: "waitlist-rate-limit",
 });