From: Chris Duncan <chris@zoso.dev>
Date: Fri, 22 Nov 2024 11:58:26 +0000 (-0800)
Subject: Eliminate remaining imported convert functions. Add type guard to initial seed ingest... 
X-Git-Url: https://zoso.dev/?a=commitdiff_plain;h=28ffe66d912a0873a9939fee2bd544ae21d40f21;p=libnemo.git

Eliminate remaining imported convert functions. Add type guard to initial seed ingestion. Pass around DataViews instead of strings.
---

diff --git a/src/lib/workers/ckdBip44.ts b/src/lib/workers/ckdBip44.ts
index a05aef4..e48156e 100644
--- a/src/lib/workers/ckdBip44.ts
+++ b/src/lib/workers/ckdBip44.ts
@@ -2,8 +2,8 @@
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 type ExtendedKey = {
-	privateKey: string
-	chainCode: string
+	privateKey: DataView
+	chainCode: DataView
 }
 
 async function ckdBip44 () {
@@ -11,12 +11,9 @@ async function ckdBip44 () {
 	const BIP44_PURPOSE = 44
 	const HARDENED_OFFSET = 0x80000000
 	const SLIP10_ED25519 = 'ed25519 seed'
-	let bytes: any
-	let hex: any
 	let addEventListener = globalThis.addEventListener
 	let postMessage = globalThis.postMessage
 	if (addEventListener == null || postMessage == null) {
-		({ bytes, hex } = await import(new URL('./dist/lib/convert.js', import.meta.url).toString()))
 		const { isMainThread, parentPort } = await import('node:worker_threads')
 		if (!isMainThread && parentPort) {
 			addEventListener = Object.getPrototypeOf(parentPort).addListener.bind(parentPort)
@@ -41,6 +38,9 @@ async function ckdBip44 () {
 	* @returns Private child key for the account
 	*/
 	async function nanoCKD (seed: string, index: number): Promise<string> {
+		if (seed.length < 32 || seed.length > 128) {
+			throw new RangeError(`Invalid seed length`)
+		}
 		if (!Number.isSafeInteger(index) || index < 0 || index > 0x7fffffff) {
 			throw new RangeError(`Invalid child key index 0x${index.toString(16)}`)
 		}
@@ -48,24 +48,29 @@ async function ckdBip44 () {
 		const purposeKey = await CKDpriv(masterKey, BIP44_PURPOSE + HARDENED_OFFSET)
 		const coinKey = await CKDpriv(purposeKey, BIP44_COIN_NANO + HARDENED_OFFSET)
 		const accountKey = await CKDpriv(coinKey, index + HARDENED_OFFSET)
-		return accountKey.privateKey
+		const privateKey = new Uint8Array(accountKey.privateKey.buffer)
+		return privateKey.reduce((key, byte) => key.concat(byte.toString(16).padStart(2, '0')), '')
 	}
 
 	async function slip10 (curve: string, S: string): Promise<ExtendedKey> {
 		const key = new TextEncoder().encode(curve)
-		const data = hex.toBytes(S)
+		const data = new Uint8Array(64)
+		data.set(S.match(/.{1,2}/g)!.map(byte => parseInt(byte, 16)))
 		const I = await hmac(key, data)
-		const IL = I.slice(0, I.length / 2)
-		const IR = I.slice(I.length / 2)
+		const IL = new DataView(I.buffer.slice(0, I.length / 2))
+		const IR = new DataView(I.buffer.slice(I.length / 2))
 		return ({ privateKey: IL, chainCode: IR })
 	}
 
 	async function CKDpriv ({ privateKey, chainCode }: ExtendedKey, index: number): Promise<ExtendedKey> {
-		const key = hex.toBytes(chainCode)
-		const data = hex.toBytes(`00${bytes.toHex(ser256(privateKey))}${bytes.toHex(ser32(index))}`)
+		const key = new Uint8Array(chainCode.buffer)
+		const data = new Uint8Array(37)
+		data.set([0])
+		data.set(ser256(privateKey), 1)
+		data.set(ser32(index), 33)
 		const I = await hmac(key, data)
-		const IL = I.slice(0, I.length / 2)
-		const IR = I.slice(I.length / 2)
+		const IL = new DataView(I.buffer.slice(0, I.length / 2))
+		const IR = new DataView(I.buffer.slice(I.length / 2))
 		return ({ privateKey: IL, chainCode: IR })
 	}
 
@@ -81,26 +86,24 @@ async function ckdBip44 () {
 		return new Uint8Array(view.buffer)
 	}
 
-	function ser256 (integer: string): Uint8Array {
-		if (typeof integer !== 'string') {
-			throw new TypeError(`Expected string, received ${typeof integer}`)
+	function ser256 (integer: DataView): Uint8Array {
+		if (integer.constructor !== DataView) {
+			throw new TypeError(`Expected DataView, received ${typeof integer}`)
 		}
-		const bits = hex.toBin(integer)
-		if (bits.length > 256) {
-			throw new RangeError(`Expected 256-bit integer, received ${bits.length}-bit value: ${integer}`)
+		if (integer.byteLength > 32) {
+			throw new RangeError(`Expected 32-byte integer, received ${integer.byteLength}-byte value: ${integer}`)
 		}
-		return hex.toBytes(integer, 32)
+		return new Uint8Array(integer.buffer)
 	}
 
-	async function hmac (key: Uint8Array, data: Uint8Array): Promise<string> {
+	async function hmac (key: Uint8Array, data: Uint8Array): Promise<Uint8Array> {
 		const { subtle } = globalThis.crypto
 		const pk = await subtle.importKey('raw', key, { name: 'HMAC', hash: 'SHA-512' }, false, ['sign'])
 		const signature = await subtle.sign('HMAC', pk, data)
-		return bytes.toHex(new Uint8Array(signature))
+		return new Uint8Array(signature)
 	}
 }
 
 const ckdBip44Worker = `(${ckdBip44.toString()})()`
-// const ckdBip44Worker = `data:text/javascript,(${ckdBip44.toString()})()`
 export { ckdBip44Worker }