wallet: Explicitly preserve scriptSig and scriptWitness in CreateTransaction

When creating a transaction with preset inputs, also preserve the
scriptSig and scriptWitness for those preset inputs if they are provided
(e.g. in fundrawtransaction).

Author: achow101

src/wallet/coincontrol.cpp

@@ -39,7 +39,10 @@ std::optional<CTxOut> CCoinControl::GetExternalOutput(const COutPoint& outpoint)
 
 PreselectedInput& CCoinControl::Select(const COutPoint& outpoint)
 {
-    return m_selected[outpoint];
+    auto& input = m_selected[outpoint];
+    input.SetPosition(m_selection_pos);
+    ++m_selection_pos;
+    return input;
 }
 void CCoinControl::UnSelect(const COutPoint& outpoint)
 {
@@ -78,6 +81,12 @@ std::optional<uint32_t> CCoinControl::GetSequence(const COutPoint& outpoint) con
     return it != m_selected.end() ? it->second.GetSequence() : std::nullopt;
 }
 
+std::pair<std::optional<CScript>, std::optional<CScriptWitness>> CCoinControl::GetScripts(const COutPoint& outpoint) const
+{
+    const auto it = m_selected.find(outpoint);
+    return it != m_selected.end() ? m_selected.at(outpoint).GetScripts() : std::make_pair(std::nullopt, std::nullopt);
+}
+
 void PreselectedInput::SetTxOut(const CTxOut& txout)
 {
     m_txout = txout;
@@ -113,4 +122,34 @@ std::optional<uint32_t> PreselectedInput::GetSequence() const
 {
     return m_sequence;
 }
+
+void PreselectedInput::SetScriptSig(const CScript& script)
+{
+    m_script_sig = script;
+}
+
+void PreselectedInput::SetScriptWitness(const CScriptWitness& script_wit)
+{
+    m_script_witness = script_wit;
+}
+
+bool PreselectedInput::HasScripts() const
+{
+    return m_script_sig.has_value() || m_script_witness.has_value();
+}
+
+std::pair<std::optional<CScript>, std::optional<CScriptWitness>> PreselectedInput::GetScripts() const
+{
+    return {m_script_sig, m_script_witness};
+}
+
+void PreselectedInput::SetPosition(unsigned int pos)
+{
+    m_pos = pos;
+}
+
+std::optional<unsigned int> PreselectedInput::GetPosition() const
+{
+    return m_pos;
+}
 } // namespace wallet

src/wallet/coincontrol.h

@@ -33,6 +33,12 @@ class PreselectedInput
     std::optional<int64_t> m_weight;
     //! The sequence number for this input
     std::optional<uint32_t> m_sequence;
+    //! The scriptSig for this input
+    std::optional<CScript> m_script_sig;
+    //! The scriptWitness for this input
+    std::optional<CScriptWitness> m_script_witness;
+    //! The position in the inputs vector for this input
+    std::optional<unsigned int> m_pos;
 
 public:
     /**
@@ -54,6 +60,20 @@ class PreselectedInput
     void SetSequence(uint32_t sequence);
     /** Retrieve the sequence for this input. */
     std::optional<uint32_t> GetSequence() const;
+
+    /** Set the scriptSig for this input. */
+    void SetScriptSig(const CScript& script);
+    /** Set the scriptWitness for this input. */
+    void SetScriptWitness(const CScriptWitness& script_wit);
+    /** Return whether either the scriptSig or scriptWitness are set for this input. */
+    bool HasScripts() const;
+    /** Retrieve both the scriptSig and the scriptWitness. */
+    std::pair<std::optional<CScript>, std::optional<CScriptWitness>> GetScripts() const;
+
+    /** Store the position of this input. */
+    void SetPosition(unsigned int pos);
+    /** Retrieve the position of this input. */
+    std::optional<unsigned int> GetPosition() const;
 };
 
 /** Coin Control Features. */
@@ -141,10 +161,27 @@ class CCoinControl
     std::optional<int64_t> GetInputWeight(const COutPoint& outpoint) const;
     /** Retrieve the sequence for an input */
     std::optional<uint32_t> GetSequence(const COutPoint& outpoint) const;
+    /** Retrieves the scriptSig and scriptWitness for an input. */
+    std::pair<std::optional<CScript>, std::optional<CScriptWitness>> GetScripts(const COutPoint& outpoint) const;
+
+    bool HasSelectedOrder() const
+    {
+        return m_selection_pos > 0;
+    }
+
+    std::optional<unsigned int> GetSelectionPos(const COutPoint& outpoint) const
+    {
+        const auto it = m_selected.find(outpoint);
+        if (it == m_selected.end()) {
+            return std::nullopt;
+        }
+        return it->second.GetPosition();
+    }
 
 private:
     //! Selected inputs (inputs that will be used, regardless of whether they're optimal or not)
     std::map<COutPoint, PreselectedInput> m_selected;
+    unsigned int m_selection_pos{0};
 };
 } // namespace wallet
 

src/wallet/spend.cpp

@@ -1146,6 +1146,25 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
     // Shuffle selected coins and fill in final vin
     std::vector<std::shared_ptr<COutput>> selected_coins = result.GetShuffledInputVector();
 
+    if (coin_control.HasSelected() && coin_control.HasSelectedOrder()) {
+        // When there are preselected inputs, we need to move them to be the first UTXOs
+        // and have them be in the order selected. We can use stable_sort for this, where we
+        // compare with the positions stored in coin_control. The COutputs that have positions
+        // will be placed before those that don't, and those positions will be in order.
+        std::stable_sort(selected_coins.begin(), selected_coins.end(),
+            [&coin_control](const std::shared_ptr<COutput>& a, const std::shared_ptr<COutput>& b) {
+                auto a_pos = coin_control.GetSelectionPos(a->outpoint);
+                auto b_pos = coin_control.GetSelectionPos(b->outpoint);
+                if (a_pos.has_value() && b_pos.has_value()) {
+                    return a_pos.value() < b_pos.value();
+                } else if (a_pos.has_value() && !b_pos.has_value()) {
+                    return true;
+                } else {
+                    return false;
+                }
+            });
+    }
+
     // The sequence number is set to non-maxint so that DiscourageFeeSniping
     // works.
     //
@@ -1162,7 +1181,15 @@ static util::Result<CreatedTransactionResult> CreateTransactionInternal(
             // If an input has a preset sequence, we can't do anti-fee-sniping
             use_anti_fee_sniping = false;
         }
-        txNew.vin.emplace_back(coin->outpoint, CScript(), sequence.value_or(default_sequence));
+        txNew.vin.emplace_back(coin->outpoint, CScript{}, sequence.value_or(default_sequence));
+
+        auto scripts = coin_control.GetScripts(coin->outpoint);
+        if (scripts.first) {
+            txNew.vin.back().scriptSig = *scripts.first;
+        }
+        if (scripts.second) {
+            txNew.vin.back().scriptWitness = *scripts.second;
+        }
     }
     if (coin_control.m_locktime) {
         txNew.nLockTime = coin_control.m_locktime.value();
@@ -1381,6 +1408,8 @@ bool FundTransaction(CWallet& wallet, CMutableTransaction& tx, CAmount& nFeeRet,
             preset_txin.SetTxOut(coins[outPoint].out);
         }
         preset_txin.SetSequence(txin.nSequence);
+        preset_txin.SetScriptSig(txin.scriptSig);
+        preset_txin.SetScriptWitness(txin.scriptWitness);
     }
 
     auto res = CreateTransaction(wallet, vecSend, nChangePosInOut, coinControl, false);