rpc: add psbt_version to (psbt)bumpfee

Also have the GUI use version 0.

src/interfaces/wallet.h

@@ -176,7 +176,7 @@ class Wallet
         CMutableTransaction& mtx) = 0;
 
     //! Sign bump transaction.
-    virtual bool signBumpTransaction(CMutableTransaction& mtx) = 0;
+    virtual bool signBumpTransaction(CMutableTransaction& mtx, const uint32_t psbt_version) = 0;
 
     //! Commit bump transaction.
     virtual bool commitBumpTransaction(const uint256& txid,

src/qt/walletmodel.cpp

@@ -556,7 +556,7 @@ bool WalletModel::bumpFee(uint256 hash, uint256& new_hash)
     assert(!m_wallet->privateKeysDisabled() || wallet().hasExternalSigner());
 
     // sign bumped transaction
-    if (!m_wallet->signBumpTransaction(mtx)) {
+    if (!m_wallet->signBumpTransaction(mtx, /*psbt_version=*/0)) {
         QMessageBox::critical(nullptr, tr("Fee bump error"), tr("Can't sign transaction."));
         return false;
     }

src/rpc/client.cpp

@@ -275,12 +275,14 @@ static const CRPCConvertParam vRPCConvertParams[] =
     { "bumpfee", 1, "replaceable"},
     { "bumpfee", 1, "outputs"},
     { "bumpfee", 1, "original_change_index"},
+    { "bumpfee", 1, "psbt_version"},
     { "psbtbumpfee", 1, "options" },
     { "psbtbumpfee", 1, "conf_target"},
     { "psbtbumpfee", 1, "fee_rate"},
     { "psbtbumpfee", 1, "replaceable"},
     { "psbtbumpfee", 1, "outputs"},
     { "psbtbumpfee", 1, "original_change_index"},
+    { "psbtbumpfee", 1, "psbt_version"},
     { "logging", 0, "include" },
     { "logging", 1, "exclude" },
     { "disconnectnode", 1, "nodeid" },

src/wallet/feebumper.cpp

@@ -333,12 +333,12 @@ Result CreateRateBumpTransaction(CWallet& wallet, const uint256& txid, const CCo
     return Result::OK;
 }
 
-bool SignTransaction(CWallet& wallet, CMutableTransaction& mtx) {
+bool SignTransaction(CWallet& wallet, CMutableTransaction& mtx, const uint32_t psbt_version) {
     LOCK(wallet.cs_wallet);
 
     if (wallet.IsWalletFlagSet(WALLET_FLAG_EXTERNAL_SIGNER)) {
         // Make a blank psbt
-        PartiallySignedTransaction psbtx(mtx);
+        PartiallySignedTransaction psbtx(mtx, psbt_version);
 
         // First fill transaction with our data without signing,
         // so external signers are not asked to sign more than once.

src/wallet/feebumper.h

@@ -60,7 +60,7 @@ Result CreateRateBumpTransaction(CWallet& wallet,
 //! Sign the new transaction,
 //! @return false if the tx couldn't be found or if it was
 //! impossible to create the signature(s)
-bool SignTransaction(CWallet& wallet, CMutableTransaction& mtx);
+bool SignTransaction(CWallet& wallet, CMutableTransaction& mtx, const uint32_t psbt_version);
 
 //! Commit the bumpfee transaction.
 //! @return success in case of CWallet::CommitTransaction was successful,

src/wallet/interfaces.cpp

@@ -319,9 +319,9 @@ class WalletImpl : public Wallet
         std::vector<CTxOut> outputs; // just an empty list of new recipients for now
         return feebumper::CreateRateBumpTransaction(*m_wallet.get(), txid, coin_control, errors, old_fee, new_fee, mtx, /* require_mine= */ true, outputs) == feebumper::Result::OK;
     }
-    bool signBumpTransaction(CMutableTransaction& mtx) override
+    bool signBumpTransaction(CMutableTransaction& mtx, const uint32_t psbt_version) override
     {
-        return feebumper::SignTransaction(*m_wallet.get(), mtx);
+        return feebumper::SignTransaction(*m_wallet.get(), mtx, psbt_version);
     }
     bool commitBumpTransaction(const uint256& txid,
         CMutableTransaction&& mtx,

src/wallet/rpc/spend.cpp

@@ -1032,6 +1032,7 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
                                                                                                                             "The remainder after paying the recipients and fees will be sent to the output script of the "
                                                                                                                             "original change output. The change output’s amount can increase if bumping the transaction "
                                                                                                                             "adds new inputs, otherwise it will decrease. Cannot be used in combination with the 'outputs' option."},
+                    {"psbt_version", RPCArg::Type::NUM, RPCArg::Default(2), "The PSBT version number to use."},
                 },
                 RPCArgOptions{.oneline_description="options"}},
         },
@@ -1071,6 +1072,7 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
     std::vector<CTxOut> outputs;
 
     std::optional<uint32_t> original_change_index;
+    uint32_t psbt_version = 2;
 
     if (!request.params[1].isNull()) {
         UniValue options = request.params[1];
@@ -1083,6 +1085,8 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
                 {"estimate_mode", UniValueType(UniValue::VSTR)},
                 {"outputs", UniValueType()}, // will be checked by AddOutputs()
                 {"original_change_index", UniValueType(UniValue::VNUM)},
+                {"psbt_version", UniValueType(UniValue::VNUM)},
+
             },
             true, true);
 
@@ -1110,6 +1114,13 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
         if (options.exists("original_change_index")) {
             original_change_index = options["original_change_index"].getInt<uint32_t>();
         }
+
+        if (!options["psbt_version"].isNull()) {
+            psbt_version = options["psbt_version"].getInt<int>();
+        }
+        if (psbt_version != 2 && psbt_version != 0) {
+            throw JSONRPCError(RPC_INVALID_PARAMETER, "The PSBT version can only be 2 or 0");
+        }
     }
 
     // Make sure the results are valid at least up to the most recent block
@@ -1153,7 +1164,7 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
     // For bumpfee, return the new transaction id.
     // For psbtbumpfee, return the base64-encoded unsigned PSBT of the new transaction.
     if (!want_psbt) {
-        if (!feebumper::SignTransaction(*pwallet, mtx)) {
+        if (!feebumper::SignTransaction(*pwallet, mtx, psbt_version)) {
             if (pwallet->IsWalletFlagSet(WALLET_FLAG_EXTERNAL_SIGNER)) {
                 throw JSONRPCError(RPC_WALLET_ERROR, "Transaction incomplete. Try psbtbumpfee instead.");
             }
@@ -1167,7 +1178,7 @@ static RPCHelpMan bumpfee_helper(std::string method_name)
 
         result.pushKV("txid", txid.GetHex());
     } else {
-        PartiallySignedTransaction psbtx(mtx, /*version=*/2);
+        PartiallySignedTransaction psbtx(mtx, psbt_version);
         bool complete = false;
         const auto err{pwallet->FillPSBT(psbtx, complete, SIGHASH_DEFAULT, /*sign=*/false, /*bip32derivs=*/true)};
         CHECK_NONFATAL(!err);