From: Ardis Lu <ardisglu@gmail.com>
Date: Sat, 25 Feb 2023 04:13:02 +0000 (-0800)
Subject: Reduce iv (nonce) size to 96 bits
X-Git-Url: https://git.ardis.lu/?a=commitdiff_plain;h=ab7abcf24b73bd19bffb7a00bc98189b72f8f395;p=static-encrypt

Reduce iv (nonce) size to 96 bits

NIST Special Publication 800-38D recommends EXACTLY 96 bits
---

diff --git a/decrypt.js b/decrypt.js
index ff85e32..cfa0606 100644
--- a/decrypt.js
+++ b/decrypt.js
@@ -3,11 +3,11 @@ export default async function decrypt(content, password) {
 
   const contentBuffer = Uint8Array.from(atob(content), c => c.charCodeAt(0));
   const salt = new Uint8Array(32);
-  const iv = new Uint8Array(32);
-  const ciphertext = new Uint8Array(contentBuffer.byteLength - 64);
+  const iv = new Uint8Array(12);
+  const ciphertext = new Uint8Array(contentBuffer.byteLength - 44);
   salt.set(contentBuffer.slice(0, 32));
-  iv.set(contentBuffer.slice(32, 64));
-  ciphertext.set(contentBuffer.slice(64));
+  iv.set(contentBuffer.slice(32, 44));
+  ciphertext.set(contentBuffer.slice(44));
 
   const keyMaterial = await crypto.subtle.importKey(
     'raw',
diff --git a/encrypt.js b/encrypt.js
index febaffa..e8ccc52 100644
--- a/encrypt.js
+++ b/encrypt.js
@@ -4,7 +4,7 @@ export default async function encrypt(plaintext, password) {
   const encodedPassword = encoder.encode(password);
 
   const salt = new Uint8Array(32);
-  const iv = new Uint8Array(32);
+  const iv = new Uint8Array(12);
   crypto.getRandomValues(salt);
   crypto.getRandomValues(iv);