From: Chris Duncan <chris@codecow.com>
Date: Sat, 29 Aug 2026 21:43:54 +0000 (-0700)
Subject: Encode errors for passing among WASM functions and out to host.
X-Git-Url: https://git.codecow.com/?a=commitdiff_plain;h=ab7c8b8ab30c74794be267a4a8a74245fa2ba310;p=nano25519.git

Encode errors for passing among WASM functions and out to host.
---

diff --git a/src/assembly/crypto_sign.ts b/src/assembly/crypto_sign.ts
index 55e2a8a..a6605ce 100644
--- a/src/assembly/crypto_sign.ts
+++ b/src/assembly/crypto_sign.ts
@@ -4,6 +4,7 @@
 import { KEY_BYTELENGTH } from '.'
 import { Blake2b } from './blake2b'
 import { crypto_derive } from './crypto_derive'
+import { errors } from './errors'
 import { ge_scalarmult_base_tobytes } from './ge'
 import { sc_muladd, sc_reduce } from './sc'
 import { clamp } from './utils'
@@ -46,7 +47,7 @@ export function crypto_sign (RS: StaticArray<u8>, M: StaticArray<u8>, mlen: i32,
 	for (let i = 0; i < KEY_BYTELENGTH; i++) {
 		c |= A[i] ^ pub[i]
 	}
-	if (c != 0) return -1
+	if (c != 0) return 1
 
 	// Hash private key to `h`
 	blake2b.init().update(prv, KEY_BYTELENGTH).digest(h)
diff --git a/src/assembly/errors.ts b/src/assembly/errors.ts
new file mode 100644
index 0000000..2dd6be1
--- /dev/null
+++ b/src/assembly/errors.ts
@@ -0,0 +1,9 @@
+//! SPDX-FileCopyrightText: 2026 Chris Duncan <chris@codecow.com>
+//! SPDX-License-Identifier: GPL-3.0-or-later
+
+export const errors = [
+    null,
+    'Invalid public key',
+    'Invalid message length',
+    'Invalid block count'
+] 
\ No newline at end of file
diff --git a/src/assembly/index.ts b/src/assembly/index.ts
index a277617..67fbdc5 100644
--- a/src/assembly/index.ts
+++ b/src/assembly/index.ts
@@ -4,6 +4,7 @@
 import { crypto_derive } from './crypto_derive'
 import { crypto_sign } from './crypto_sign'
 import { crypto_verify_decodepubkey, crypto_verify_relaxed, crypto_verify_strict } from './crypto_verify'
+import { errors } from './errors'
 
 export const BLOCKHASH_BYTELENGTH: i32 = 32
 export const KEY_BYTELENGTH: i32 = 32
@@ -121,7 +122,7 @@ export function sign (mlen: i32): void {
 		INPUT_PRV.fill(0)
 		INPUT_PUB.fill(0)
 		INPUT_MSG.fill(0)
-		throw new Error('Invalid message length')
+		throw new Error(errors[2])
 	}
 
 	// Copy input buffers to local parameters, then clear input buffer
@@ -139,7 +140,7 @@ export function sign (mlen: i32): void {
 	// Clear signature output buffer if signing failed	
 	if (result != 0) {
 		OUTPUT_SIGN.fill(0)
-		throw new Error('Failed to sign, check keypair and message are valid')
+		throw new Error(errors[result])
 	}
 }
 
@@ -161,7 +162,7 @@ export function verify (mlen: i32): void {
 	if (mlen < 0 || mlen > MAX_MESSAGE_BYTELENGTH) {
 		INPUT_MSG.fill(0)
 		INPUT_PUB.fill(0)
-		throw new Error('Invalid message length')
+		throw new Error(errors[2])
 	}
 
 	// Copy input buffer to local parameters, then clear input buffer
@@ -209,7 +210,7 @@ export function verify_blocks (count: i32): void {
 	if (count < 1 || MAX_VERIFY_BLOCKS < count) {
 		INPUT_MSG.fill(0)
 		INPUT_PUB.fill(0)
-		throw new Error('Invalid block count')
+		throw new Error(errors[3])
 	}
 
 	// Copy public key input buffer to local parameter, then clear input buffer