Add support for SIGHASH_DEFAULT in RPCs, and make it default

For non-Taproot signatures, this is interpreted as SIGHASH_ALL.

1 files changed, 5 insertions, 2 deletions

diff --git a/src/script/sign.cpp b/src/script/sign.cpp
index 749bcc173c..65276f641f 100644
--- a/src/script/sign.cpp
+++ b/src/script/sign.cpp
@@ -44,10 +44,13 @@ bool MutableTransactionSignatureCreator::CreateSig(const SigningProvider& provid
     // Signing without known amount does not work in witness scripts.
     if (sigversion == SigVersion::WITNESS_V0 && !MoneyRange(amount)) return false;
 
-    uint256 hash = SignatureHash(scriptCode, *txTo, nIn, nHashType, amount, sigversion, m_txdata);
+    // BASE/WITNESS_V0 signatures don't support explicit SIGHASH_DEFAULT, use SIGHASH_ALL instead.
+    const int hashtype = nHashType == SIGHASH_DEFAULT ? SIGHASH_ALL : nHashType;
+
+    uint256 hash = SignatureHash(scriptCode, *txTo, nIn, hashtype, amount, sigversion, m_txdata);
     if (!key.Sign(hash, vchSig))
         return false;
-    vchSig.push_back((unsigned char)nHashType);
+    vchSig.push_back((unsigned char)hashtype);
     return true;
 }