From 4a5dc88e2da69b56cc5bdb0f0fde2f20a58c4d2d Mon Sep 17 00:00:00 2001
From: Sahin Vardar <sahin@vardar.io>
Date: Sun, 25 Feb 2024 12:19:54 +0100
Subject: [PATCH] removed the need for @lukeed/csprng

---
 package.json   |  2 --
 pnpm-lock.yaml | 19 -------------------
 src/utils.ts   | 27 +++++++++++++++++++++++++--
 3 files changed, 25 insertions(+), 23 deletions(-)

diff --git a/package.json b/package.json
index c0ac5c1..49d67bf 100644
--- a/package.json
+++ b/package.json
@@ -22,7 +22,6 @@
     "watch": "tsc --build --watch"
   },
   "dependencies": {
-    "@lukeed/csprng": "^1.1.0",
     "buffer": "^6.0.3",
     "date-fns-tz": "^2.0.0",
     "hash.js": "^1.1.7",
@@ -32,7 +31,6 @@
     "@aws-sdk/client-cognito-identity-provider": "^3.465.0",
     "@types/jsbn": "^1.2.33",
     "@types/jsdom": "^21.1.5",
-    "@types/randombytes": "^2.0.3",
     "@typescript-eslint/eslint-plugin": "^6.11.0",
     "@typescript-eslint/parser": "^6.11.0",
     "eslint": "^8.54.0",
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index db50f4e..ef2a261 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -7,9 +7,6 @@ settings:
 importers:
   .:
     dependencies:
-      '@lukeed/csprng':
-        specifier: ^1.1.0
-        version: 1.1.0
       buffer:
         specifier: ^6.0.3
         version: 6.0.3
@@ -32,9 +29,6 @@ importers:
       '@types/jsdom':
         specifier: ^21.1.5
         version: 21.1.5
-      '@types/randombytes':
-        specifier: ^2.0.3
-        version: 2.0.3
       '@typescript-eslint/eslint-plugin':
         specifier: ^6.11.0
         version: 6.11.0(@typescript-eslint/parser@6.11.0)(eslint@8.54.0)(typescript@5.2.2)
@@ -1615,12 +1609,6 @@ packages:
       '@jridgewell/sourcemap-codec': 1.4.15
     dev: true
 
-  /@lukeed/csprng@1.1.0:
-    resolution:
-      { integrity: sha512-Z7C/xXCiGWsg0KuKsHTKJxbWhpI3Vs5GwLfOean7MGyVFGqdRgBbAjOCh6u4bbjPc/8MJ2pZmK/0DLdCbivLDA== }
-    engines: { node: '>=8' }
-    dev: false
-
   /@nodelib/fs.scandir@2.1.5:
     resolution:
       { integrity: sha512-vq24Bq3ym5HEQm2NKCr3yXDwjc7vTsEThRDnkp2DK9p1uqLR+DHurm/NOTo0KG7HYHU7eppKZj3MyqYuMBf62g== }
@@ -2548,13 +2536,6 @@ packages:
       { integrity: sha512-dISoDXWWQwUquiKsyZ4Ng+HX2KsPL7LyHKHQwgGFEA3IaKac4Obd+h2a/a6waisAoepJlBcx9paWqjA8/HVjCw== }
     dev: true
 
-  /@types/randombytes@2.0.3:
-    resolution:
-      { integrity: sha512-+NRgihTfuURllWCiIAhm1wsJqzsocnqXM77V/CalsdJIYSRGEHMnritxh+6EsBklshC+clo1KgnN14qgSGeQdw== }
-    dependencies:
-      '@types/node': 20.9.1
-    dev: true
-
   /@types/semver@7.5.5:
     resolution:
       { integrity: sha512-+d+WYC1BxJ6yVOgUgzK8gWvp5qF8ssV5r4nsDcZWKRWcDQLQ619tvWAxJQYGgBrO1MnLJC7a5GtiYsAoQ47dJg== }
diff --git a/src/utils.ts b/src/utils.ts
index 2895b4a..ad8d8bb 100644
--- a/src/utils.ts
+++ b/src/utils.ts
@@ -2,7 +2,6 @@ import hashJs from 'hash.js';
 import { BigInteger } from 'jsbn';
 import { Buffer } from 'buffer';
 import formatInTimeZone from 'date-fns-tz/formatInTimeZone';
-import { random } from '@lukeed/csprng';
 
 const initN =
   'FFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD1' +
@@ -156,7 +155,7 @@ export function decodeJwt<T = unknown>(jwt: string) {
 }
 
 export async function randomBytes(num: number) {
-  return random(num);
+  return Buffer.from(crypto.getRandomValues(new Uint8Array(num)));
 }
 
 export function formatTimestamp(date: Date) {
@@ -174,3 +173,27 @@ export function calculateSecretHash(clientSecret: string, userPoolClientId: stri
 
   return hash;
 }
+
+export async function digest(algorithm: AlgorithmIdentifier, str: string) {
+  const buffer = new TextEncoder().encode(str);
+  const hashBuffer = await crypto.subtle.digest(algorithm, buffer);
+  return Array.from(new Uint8Array(hashBuffer))
+    .map(b => b.toString(16).padStart(2, '0'))
+    .join('');
+}
+
+export async function hmac(algorithm: AlgorithmIdentifier, key: string, data: string) {
+  const enc = new TextEncoder();
+  const cryptoKey = await crypto.subtle.importKey(
+    'raw',
+    enc.encode(key),
+    {
+      name: 'HMAC',
+      hash: algorithm
+    },
+    false,
+    ['sign']
+  );
+  const signature = await crypto.subtle.sign(algorithm, cryptoKey, enc.encode(data));
+  return new Uint8Array(signature);
+}