From: Chris Duncan <chris@zoso.dev>
Date: Sat, 9 Aug 2025 07:22:55 +0000 (-0700)
Subject: Simplify BIP-39 seed gen by deriving bits directly.
X-Git-Tag: v0.10.5~41^2~152
X-Git-Url: https://git.codecow.com/?a=commitdiff_plain;h=f118c32383783eb73754fa701697ad3a6ae000f5;p=libnemo.git

Simplify BIP-39 seed gen by deriving bits directly.
---

diff --git a/src/lib/crypto/bip39.ts b/src/lib/crypto/bip39.ts
index f30120b..bd94034 100644
--- a/src/lib/crypto/bip39.ts
+++ b/src/lib/crypto/bip39.ts
@@ -199,21 +199,14 @@ export class Bip39 {
 				: passphrase
 			const keyData = utf8.toBytes(this.phrase)
 			const phraseKey = await crypto.subtle.importKey('raw', keyData, 'PBKDF2', false, ['deriveBits', 'deriveKey'])
-			const derivedKeyType: HmacImportParams = {
-				name: 'HMAC',
-				hash: 'SHA-512',
-				length: 512
-			}
-
 			const algorithm: Pbkdf2Params = {
 				name: 'PBKDF2',
 				hash: 'SHA-512',
 				salt: utf8.toBytes(`mnemonic${salt.normalize('NFKD')}`),
 				iterations: BIP39_ITERATIONS
 			}
-			const seedKey = await crypto.subtle.deriveKey(algorithm, phraseKey, derivedKeyType, true, ['sign'])
-			const seedBuffer = await crypto.subtle.exportKey('raw', seedKey)
-			this.#bip39Seed = new Uint8Array(seedBuffer)
+			const seed = await crypto.subtle.deriveBits(algorithm, phraseKey, 512)
+			this.#bip39Seed = new Uint8Array(seed)
 		}
 		return format === 'hex'
 			? bytes.toHex(this.#bip39Seed)