From 2a22f034ca3298c9f86d1edd4283a0bea18dfbbe Mon Sep 17 00:00:00 2001
From: avirgovi <avirgovi@cisco.com>
Date: Thu, 28 Apr 2022 19:52:51 +0200
Subject: [PATCH] parsing external signer master fingerprint string as bytes
 instead of caring for lower/upper case in ExternalSigner::SignTransaction

---
 src/external_signer.cpp | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/src/external_signer.cpp b/src/external_signer.cpp
index 75070899c6..d125fe479b 100644
--- a/src/external_signer.cpp
+++ b/src/external_signer.cpp
@@ -74,11 +74,12 @@ bool ExternalSigner::SignTransaction(PartiallySignedTransaction& psbtx, std::str
     // Serialize the PSBT
     CDataStream ssTx(SER_NETWORK, PROTOCOL_VERSION);
     ssTx << psbtx;
-
+    // parse ExternalSigner master fingerprint
+    std::vector<unsigned char> parsed_m_fingerprint = ParseHex(m_fingerprint);
     // Check if signer fingerprint matches any input master key fingerprint
     auto matches_signer_fingerprint = [&](const PSBTInput& input) {
         for (const auto& entry : input.hd_keypaths) {
-            if (m_fingerprint == strprintf("%08x", ReadBE32(entry.second.fingerprint))) return true;
+            if (parsed_m_fingerprint == MakeUCharSpan(entry.second.fingerprint)) return true;
         }
         return false;
     };