From c830107bce1555cfa66e59d39bbb9dbd79ca94f1 Mon Sep 17 00:00:00 2001
From: Sean Gilligan <sean@msgilligan.com>
Date: Tue, 12 Sep 2023 10:45:27 -0700
Subject: [PATCH] PBKDF2SHA512: set hLen to correct value of 64

This is a bugfix to the API, but since `MnemonicCode` always
passes `dkLen` of 64 and the `System.arraycopy()` on line 66 truncates
`baos.toByteArray()` to `dkLen` length, the call to `derive()` works
correctly for our use-case.
---
 core/src/main/java/org/bitcoinj/crypto/PBKDF2SHA512.java | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/core/src/main/java/org/bitcoinj/crypto/PBKDF2SHA512.java b/core/src/main/java/org/bitcoinj/crypto/PBKDF2SHA512.java
index 32437f652..94671e117 100644
--- a/core/src/main/java/org/bitcoinj/crypto/PBKDF2SHA512.java
+++ b/core/src/main/java/org/bitcoinj/crypto/PBKDF2SHA512.java
@@ -41,7 +41,7 @@ public class PBKDF2SHA512 {
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
 
         try {
-            int hLen = 20;
+            int hLen = 64;          // Length of HMAC result
 
             if (dkLen > ((Math.pow(2, 32)) - 1) * hLen) {
                 throw new IllegalArgumentException("derived key too long");