From b70f7c5a9564908092447a0aafa6f29f2269878c Mon Sep 17 00:00:00 2001
From: Franck Royer <franck@status.im>
Date: Fri, 9 Jul 2021 15:48:25 +1000
Subject: [PATCH] Use DOM random generator if available

---
 src/lib/waku_message/version_1.ts | 23 +++++++++++++++++++----
 tsconfig.json                     |  2 +-
 2 files changed, 20 insertions(+), 5 deletions(-)

diff --git a/src/lib/waku_message/version_1.ts b/src/lib/waku_message/version_1.ts
index 0749fbb68e..96c314aac3 100644
--- a/src/lib/waku_message/version_1.ts
+++ b/src/lib/waku_message/version_1.ts
@@ -1,5 +1,4 @@
 import { Buffer } from 'buffer';
-import { randomBytes } from 'crypto';
 import * as crypto from 'crypto';
 
 import ecies from 'ecies-parity';
@@ -127,7 +126,7 @@ export async function decryptAsymmetric(
  * Generate a new private key
  */
 export function generatePrivateKey(): Uint8Array {
-  return crypto.randomBytes(32);
+  return randomBytes(32);
 }
 
 /**
@@ -161,12 +160,18 @@ function getSizeOfPayloadSizeField(payload: Uint8Array): number {
   return s;
 }
 
-function validateDataIntegrity(value: Buffer, expectedSize: number): boolean {
+function validateDataIntegrity(
+  value: Uint8Array,
+  expectedSize: number
+): boolean {
   if (value.length !== expectedSize) {
     return false;
   }
 
-  if (expectedSize > 3 && value.equals(Buffer.alloc(value.length))) {
+  if (
+    expectedSize > 3 &&
+    Buffer.from(value).equals(Buffer.alloc(value.length))
+  ) {
     return false;
   }
 
@@ -193,3 +198,13 @@ function ecRecoverPubKey(messageHash: string, signature: Buffer): Uint8Array {
     false
   );
 }
+
+function randomBytes(length: number): Uint8Array {
+  if (typeof window !== 'undefined' && window && window.crypto) {
+    const array = new Uint8Array(length);
+    window.crypto.getRandomValues(array);
+    return array;
+  } else {
+    return crypto.randomBytes(length);
+  }
+}
diff --git a/tsconfig.json b/tsconfig.json
index 3edb3bcf13..544cde09a7 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -41,7 +41,7 @@
     // "experimentalDecorators": true /* Enables experimental support for ES7 decorators. */,
     // "emitDecoratorMetadata": true /* Enables experimental support for emitting type metadata for decorators. */,
 
-    "lib": ["es2017"],
+    "lib": ["es2017", "dom"],
     "types": ["node", "mocha"],
     "typeRoots": ["node_modules/@types", "src/types"]
   },