From 710bb5dea3131134552a837b8072c8f6670969d0 Mon Sep 17 00:00:00 2001
From: Phillip Ho <arcoraven@gmail.com>
Date: Wed, 10 Jan 2024 08:00:31 +0900
Subject: [PATCH] fix: disallow localhost webhooks (#368)

* fix: disallow localhost webhooks

* allow http but disallow localhost
---
 src/server/routes/webhooks/create.ts | 45 +++++++++++++---------------
 src/tests/url.test.ts                | 23 ++++++++++++++
 src/utils/url.ts                     |  8 +++++
 3 files changed, 51 insertions(+), 25 deletions(-)
 create mode 100644 src/tests/url.test.ts
 create mode 100644 src/utils/url.ts

diff --git a/src/server/routes/webhooks/create.ts b/src/server/routes/webhooks/create.ts
index 747a4e483..15fada81c 100644
--- a/src/server/routes/webhooks/create.ts
+++ b/src/server/routes/webhooks/create.ts
@@ -4,35 +4,29 @@ import { FastifyInstance } from "fastify";
 import { StatusCodes } from "http-status-codes";
 import { insertWebhook } from "../../../db/webhooks/createWebhook";
 import { WebhooksEventTypes } from "../../../schema/webhooks";
+import { isLocalhost } from "../../../utils/url";
 import { standardResponseSchema } from "../../schemas/sharedApiSchemas";
 
 const uriFormat = TypeSystem.Format("uri", (input: string) => {
+  // Assert valid URL.
   try {
-    if (input.startsWith("http://localhost")) return true;
-
-    const url = new URL(input);
-
-    if (url.protocol === "http:") {
-      return false;
-    }
-    return true;
+    new URL(input);
   } catch (err) {
     return false;
   }
+
+  return !isLocalhost(input);
 });
 
 const BodySchema = Type.Object({
   url: Type.String({
-    description: "URL to send the webhook to",
+    description: "Webhook URL",
     format: uriFormat,
-    examples: [
-      "http://localhost:3000/webhooks",
-      "https://example.com/webhooks",
-    ],
+    examples: ["https://example.com/webhooks"],
   }),
   name: Type.Optional(
     Type.String({
-      minLength: 5,
+      minLength: 3,
     }),
   ),
   eventType: Type.Enum(WebhooksEventTypes),
@@ -40,47 +34,47 @@ const BodySchema = Type.Object({
 
 BodySchema.examples = [
   {
-    url: "http://localhost:3000/allTxUpdate",
+    url: "https://example.com/allTxUpdate",
     name: "All Transaction Events",
     eventType: WebhooksEventTypes.ALL_TX,
   },
   {
-    url: "http://localhost:3000/queuedTx",
+    url: "https://example.com/queuedTx",
     name: "QueuedTx",
     eventType: WebhooksEventTypes.QUEUED_TX,
   },
   {
-    url: "http://localhost:3000/retiredTx",
+    url: "https://example.com/retiredTx",
     name: "RetriedTx",
     eventType: WebhooksEventTypes.RETRIED_TX,
   },
   {
-    url: "http://localhost:3000/sentTx",
+    url: "https://example.com/sentTx",
     name: "Sent Transaction Event",
     eventType: WebhooksEventTypes.SENT_TX,
   },
   {
-    url: "http://localhost:3000/minedTx",
+    url: "https://example.com/minedTx",
     name: "Mined Transaction Event",
     eventType: WebhooksEventTypes.MINED_TX,
   },
   {
-    url: "http://localhost:3000/erroredTx",
+    url: "https://example.com/erroredTx",
     name: "Errored Transaction Event",
     eventType: WebhooksEventTypes.ERRORED_TX,
   },
   {
-    url: "http://localhost:3000/cancelledTx",
+    url: "https://example.com/cancelledTx",
     name: "Cancelled Transaction Event",
     eventType: WebhooksEventTypes.CANCELLED_TX,
   },
   {
-    url: "http://localhost:3000/walletBalance",
+    url: "https://example.com/walletBalance",
     name: "Backend Wallet Balance Event",
     eventType: WebhooksEventTypes.BACKEND_WALLET_BALANCE,
   },
   {
-    url: "http://localhost:3000/auth",
+    url: "https://example.com/auth",
     name: "Auth Check",
     eventType: WebhooksEventTypes.AUTH,
   },
@@ -104,8 +98,9 @@ export async function createWebhook(fastify: FastifyInstance) {
     method: "POST",
     url: "/webhooks/create",
     schema: {
-      summary: "Create a new webhook",
-      description: "Create a new webhook",
+      summary: "Create a webhook",
+      description:
+        "Create a webhook to call when certain blockchain events occur.",
       tags: ["Webhooks"],
       operationId: "create",
       body: BodySchema,
diff --git a/src/tests/url.test.ts b/src/tests/url.test.ts
new file mode 100644
index 000000000..53f6bd3d5
--- /dev/null
+++ b/src/tests/url.test.ts
@@ -0,0 +1,23 @@
+import { isLocalhost } from "../utils/url";
+
+describe("isLocalhost function", () => {
+  test("should return true for localhost URL", () => {
+    const localhostUrl = "http://localhost:3000/path";
+    expect(isLocalhost(localhostUrl)).toBe(true);
+  });
+
+  test("should return true for 127.0.0.1 URL", () => {
+    const ipUrl = "http://127.0.0.1:8080/path";
+    expect(isLocalhost(ipUrl)).toBe(true);
+  });
+
+  test("should return false for external URL", () => {
+    const externalUrl = "http://example.com/path";
+    expect(isLocalhost(externalUrl)).toBe(false);
+  });
+
+  test("should return false for invalid URL", () => {
+    const invalidUrl = "not_a_url";
+    expect(isLocalhost(invalidUrl)).toBe(false);
+  });
+});
diff --git a/src/utils/url.ts b/src/utils/url.ts
new file mode 100644
index 000000000..9c4eefef1
--- /dev/null
+++ b/src/utils/url.ts
@@ -0,0 +1,8 @@
+export const isLocalhost = (url: string) => {
+  try {
+    const parsed = new URL(url);
+    return parsed.hostname === "localhost" || parsed.hostname === "127.0.0.1";
+  } catch (err) {
+    return false;
+  }
+};