From: Chris Duncan <chris@zoso.dev>
Date: Wed, 23 Sep 2026 19:41:27 +0000 (-0700)
Subject: Clear WASM I/O buffers with host-side call to export instead of using setters and... 
X-Git-Url: https://git.codecow.com/?a=commitdiff_plain;h=72974c02ffc4a5bdc23beefca4ab4f821d317d18;p=nano25519.git

Clear WASM I/O buffers with host-side call to export instead of using setters and getters.
---

diff --git a/src/assembly/index.ts b/src/assembly/index.ts
index 5eaf811..d300801 100644
--- a/src/assembly/index.ts
+++ b/src/assembly/index.ts
@@ -19,6 +19,17 @@ const OUTPUT_DERIVE = new StaticArray<u8>(KEY_BYTELENGTH)
 const OUTPUT_SIGN = new StaticArray<u8>(SIGNATURE_BYTELENGTH)
 const OUTPUT_VERIFY = new StaticArray<u8>(MAX_VERIFY_BLOCKS)
 
+/** Clears all input and output buffers. */
+export function clearMemory (): void {
+	INPUT_MSG.fill(0)
+	INPUT_PRV.fill(0)
+	INPUT_PUB.fill(0)
+	INPUT_SIG.fill(0)
+	OUTPUT_DERIVE.fill(0)
+	OUTPUT_SIGN.fill(0)
+	OUTPUT_VERIFY.fill(0)
+}
+
 /** Sets a byte in the static message input buffer. */
 export function setInputMsgByte (index: i32, v0: i32): i32 {
 	if (index < 0 || MAX_MESSAGE_BYTELENGTH <= index) {
diff --git a/src/lib/wasm.ts b/src/lib/wasm.ts
index 16e67d2..cb62d4b 100644
--- a/src/lib/wasm.ts
+++ b/src/lib/wasm.ts
@@ -6,6 +6,7 @@ import nano25519_wasm from '../../build/nano25519.wasm'
 import { Nano25519TypeError, copy } from './primordials'
 
 type Exports = WebAssembly.Instance['exports'] & {
+	clearMemory: () => void
 	derive: () => void
 	sign: (mlen: number) => number
 	verify: (mlen: number) => number
@@ -91,18 +92,7 @@ export class MemoryBuffers {
 }
 
 export function clearMemory (): void {
-	for (let i = 0; i < MAX_MESSAGE_BYTELENGTH; i++) {
-		MemoryBuffers.INPUT_MSG(i)(0)
-	}
-	for (let i = 0; i < KEY_BYTELENGTH; i++) {
-		MemoryBuffers.INPUT_PRV(i)(0)
-	}
-	for (let i = 0; i < KEY_BYTELENGTH; i++) {
-		MemoryBuffers.INPUT_PUB(i)(0)
-	}
-	for (let i = 0; i < SIGNATURE_BYTELENGTH; i++) {
-		MemoryBuffers.INPUT_SIG(i)(0)
-	}
+	exports.clearMemory()
 	locked = false
 }