GUI/Options: Configure maxscriptsize using settings

src/qt/optionsdialog.cpp

@@ -307,6 +307,12 @@ OptionsDialog::OptionsDialog(QWidget* parent, bool enableWallet)
     verticalLayout_Spamfiltering->addWidget(rejectbaremultisig);
     FixTabOrder(rejectbaremultisig);
 
+    maxscriptsize = new QSpinBox(groupBox_Spamfiltering);
+    maxscriptsize->setMinimum(0);
+    maxscriptsize->setMaximum(std::numeric_limits<int>::max());
+    maxscriptsize->setToolTip(tr("There may be rare smart contracts that require a large amount of code, but more often a larger code segment is actually just spam finding new ways to try to evade filtering. 1650 bytes is sometimes considered the high end of what might be normal, usually for N-of-20 multisig."));
+    CreateOptionUI(verticalLayout_Spamfiltering, maxscriptsize, tr("Ignore transactions with smart contract code larger than %s bytes."));
+
     datacarriersize = new QSpinBox(groupBox_Spamfiltering);
     datacarriersize->setMinimum(0);
     datacarriersize->setMaximum(std::numeric_limits<int>::max());
@@ -627,6 +633,7 @@ void OptionsDialog::setMapper()
     mapper->addMapping(limitdescendantcount, OptionsModel::limitdescendantcount);
     mapper->addMapping(limitdescendantsize, OptionsModel::limitdescendantsize);
     mapper->addMapping(rejectbaremultisig, OptionsModel::rejectbaremultisig);
+    mapper->addMapping(maxscriptsize, OptionsModel::maxscriptsize);
     mapper->addMapping(datacarriercost, OptionsModel::datacarriercost);
     mapper->addMapping(datacarriersize, OptionsModel::datacarriersize);
     mapper->addMapping(dustrelayfee, OptionsModel::dustrelayfee);

src/qt/optionsdialog.h

@@ -115,6 +115,7 @@ private:
     QSpinBox *limitdescendantcount;
     QSpinBox *limitdescendantsize;
     QCheckBox *rejectbaremultisig;
+    QSpinBox *maxscriptsize;
     QSpinBox *datacarriersize;
     QDoubleSpinBox *datacarriercost;
     BitcoinAmountField *dustrelayfee;

src/qt/optionsmodel.cpp

@@ -675,6 +675,8 @@ QVariant OptionsModel::getOption(OptionID option, const std::string& suffix) con
         return qlonglong(node().mempool().m_opts.limits.descendant_size_vbytes / 1'000);
     case rejectbaremultisig:
         return !node().mempool().m_opts.permit_bare_multisig;
+    case maxscriptsize:
+        return ::g_script_size_policy_limit;
     case datacarriercost:
         return double(::g_weight_per_data_byte) / WITNESS_SCALE_FACTOR;
     case datacarriersize:
@@ -1175,6 +1177,13 @@ bool OptionsModel::setOption(OptionID option, const QVariant& value, const std::
             gArgs.ModifyRWConfigFile("permitbaremultisig", strprintf("%d", fNewValue));
         }
         break;
+    case maxscriptsize:
+        if (changed()) {
+            const auto nv = value.toLongLong();
+            update(nv);
+            ::g_script_size_policy_limit = nv;
+        }
+        break;
     case datacarriercost:
         if (changed()) {
             const double nNewSize = value.toDouble();

src/qt/optionsmodel.h

@@ -96,6 +96,7 @@ public:
         limitdescendantcount,
         limitdescendantsize,
         rejectbaremultisig,     // bool
+        maxscriptsize,
         datacarriercost,        // double
         datacarriersize,
         dustrelayfee,