From 7fefaf0818417f1cc4ae0c9f360e5b08734d68f3 Mon Sep 17 00:00:00 2001
From: Derrick Hammer <derrick@derrickhammer.com>
Date: Sun, 20 Aug 2023 02:35:17 -0400
Subject: [PATCH] feat: change deriveChildKey to hkdf sha256 and create
 deriveBlakeChildKey that hashes based on the initial blake3 route used by s5

---
 src/keys.ts | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/src/keys.ts b/src/keys.ts
index 83e3e25..e5f30ad 100644
--- a/src/keys.ts
+++ b/src/keys.ts
@@ -1,9 +1,18 @@
 import { blake3 } from "@noble/hashes/blake3";
 import { concatBytes } from "@noble/hashes/utils";
+import { hkdf } from "@noble/hashes/hkdf";
+import { sha256 } from "@noble/hashes/sha256";
 
 export function deriveChildKey(
   parentKey: Uint8Array,
   tweak: string,
+): Uint8Array {
+  return hkdf(sha256, parentKey, undefined, tweak, 32);
+}
+
+export function deriveBlakeChildKey(
+  parentKey: Uint8Array,
+  tweak: string,
 ): Uint8Array {
   const tweakHash = blake3(tweak);