add pegin_witness to witness inputs

src/primitives/transaction.cpp

@@ -97,29 +97,18 @@ CMutableTransaction::CMutableTransaction() : nVersion(CTransaction::CURRENT_VERS
 CMutableTransaction::CMutableTransaction(const CTransaction& tx) : nVersion(tx.nVersion), vin(tx.vin), vout(tx.vout), wit(tx.wit), nLockTime(tx.nLockTime) {}
 
 /**
- * The input witness consists of three elements, two of which are
+ * The input witness consists of four elements, three of which are
  * optional. The optional elements have to do with asset issuance
- * and are not normally present, most of the time. For this reason
+ * and peg-in transactions, nor present most of the time.
- * the optional elements are places in a lower branch of the Merkle
- * tree. When not present, they take on constant values in the hash
- * tree.
  *
- *     S : script witness
+  */
- *     A : issuance amount rangeproof
- *     I : inflation keys rangeproof
- *
- *             .
- *            / \
- *           .   S
- *          / \
- *         A   I
- */
 uint256 CTxInWitness::GetHash() const
 {
     std::vector<uint256> leaves;
     leaves.push_back(SerializeHash(vchIssuanceAmountRangeproof, SER_GETHASH, 0));
     leaves.push_back(SerializeHash(vchInflationKeysRangeproof, SER_GETHASH, 0));
     leaves.push_back(SerializeHash(scriptWitness.stack, SER_GETHASH, 0));
+    leaves.push_back(SerializeHash(m_pegin_witness.stack, SER_GETHASH, 0));
     return ComputeFastMerkleRoot(leaves);
 }
 

src/primitives/transaction.h

@@ -509,9 +509,12 @@ public:
 class CTxInWitness
 {
 public:
+    // TODO generalize CScriptWitness into just CWitness
     std::vector<unsigned char> vchIssuanceAmountRangeproof;
     std::vector<unsigned char> vchInflationKeysRangeproof;
     CScriptWitness scriptWitness;
+    // Re-use script witness struct to include its own witness
+    CScriptWitness m_pegin_witness;
 
     ADD_SERIALIZE_METHODS;
 
@@ -521,19 +524,21 @@ public:
         READWRITE(vchIssuanceAmountRangeproof);
         READWRITE(vchInflationKeysRangeproof);
         READWRITE(scriptWitness.stack);
+        READWRITE(m_pegin_witness.stack);
     }
 
     CTxInWitness() { }
 
     bool IsNull() const
     {
-        return vchIssuanceAmountRangeproof.empty() && vchInflationKeysRangeproof.empty() && scriptWitness.IsNull();
+        return vchIssuanceAmountRangeproof.empty() && vchInflationKeysRangeproof.empty() && scriptWitness.IsNull() && m_pegin_witness.IsNull();
     }
     void SetNull()
     {
         vchIssuanceAmountRangeproof.clear();
         vchInflationKeysRangeproof.clear();
         scriptWitness.stack.clear();
+        m_pegin_witness.stack.clear();
     }
 
     uint256 GetHash() const;