From 10d463a51272f1fbbf9dc8600460393fc44eab18 Mon Sep 17 00:00:00 2001
From: Arseniy Klempner <adklempner@gmail.com>
Date: Thu, 21 Mar 2024 20:49:28 -0700
Subject: [PATCH] fix: use correct offset when converting commitment to bigint

---
 src/identity.ts    | 2 +-
 src/utils/bytes.ts | 7 +++++--
 2 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/src/identity.ts b/src/identity.ts
index 06cd436..ecd64ca 100644
--- a/src/identity.ts
+++ b/src/identity.ts
@@ -14,7 +14,7 @@ export class IdentityCredential {
     const idNullifier = memKeys.subarray(32, 64);
     const idSecretHash = memKeys.subarray(64, 96);
     const idCommitment = memKeys.subarray(96);
-    const idCommitmentBigInt = buildBigIntFromUint8Array(idCommitment);
+    const idCommitmentBigInt = buildBigIntFromUint8Array(idCommitment, 96);
 
     return new IdentityCredential(
       idTrapdoor,
diff --git a/src/utils/bytes.ts b/src/utils/bytes.ts
index 000488c..279a2b3 100644
--- a/src/utils/bytes.ts
+++ b/src/utils/bytes.ts
@@ -61,9 +61,12 @@ export function writeUIntLE(
  * @param array: Uint8Array
  * @returns BigInt
  */
-export function buildBigIntFromUint8Array(array: Uint8Array): bigint {
+export function buildBigIntFromUint8Array(
+  array: Uint8Array,
+  byteOffset: number = 0
+): bigint {
   const dataView = new DataView(array.buffer);
-  return dataView.getBigUint64(0, true);
+  return dataView.getBigUint64(byteOffset, true);
 }
 
 /**