Add PourProver interface for slowly morphing the API into something t…

…hat zcash can interact with nicer. This is obviously only a step in the right direction.

Makefile

@@ -39,6 +39,7 @@ SRCS= \
 	$(LIBZEROCASH)/MintTransaction.cpp \
 	$(LIBZEROCASH)/PourInput.cpp \
 	$(LIBZEROCASH)/PourOutput.cpp \
+	$(LIBZEROCASH)/PourProver.cpp \
 	$(LIBZEROCASH)/PourTransaction.cpp \
 	$(LIBZEROCASH)/ZerocashParams.cpp \
 	$(TESTUTILS)/timer.cpp

libzerocash/CoinCommitment.h

@@ -21,6 +21,7 @@ namespace libzerocash {
 class CoinCommitment {
 
 friend class PourTransaction;
+friend class PourProver;
 
 public:
 	CoinCommitment();

libzerocash/PourProver.cpp

@@ -0,0 +1,12 @@
+/** @file
+*****************************************************************************
+
+Implementation of interfaces for the class PourProver.
+
+*****************************************************************************
+* @author     This file is part of libzerocash, developed by the Zerocash
+*             project and contributors (see AUTHORS).
+* @copyright  MIT license (see LICENSE file)
+*****************************************************************************/
+
+#include "PourProver.h"

libzerocash/PourProver.h

@@ -0,0 +1,65 @@
+/** @file
+ *****************************************************************************
+
+ Declaration of interfaces for the class PourProver.
+
+ *****************************************************************************
+ * @author     This file is part of libzerocash, developed by the Zerocash
+ *             project and contributors (see AUTHORS).
+ * @copyright  MIT license (see LICENSE file)
+ *****************************************************************************/
+
+#ifndef POURPROVER_H_
+#define POURPROVER_H_
+
+#include "ZerocashParams.h"
+#include "boost/array.hpp"
+#include "PourTransaction.h"
+#include "CoinCommitment.h"
+
+namespace libzerocash {
+
+class PourProver {
+public:
+	static bool VerifyProof(
+		ZerocashParams& params,
+		const std::vector<unsigned char>& pubkeyHash,
+		const std::vector<unsigned char>& rt,
+		const uint64_t vpub_old,
+        const uint64_t vpub_new,
+		const boost::array<std::vector<unsigned char>, 2> serials,
+		const boost::array<std::vector<unsigned char>, 2> commitments,
+		const boost::array<std::vector<unsigned char>, 2> macs,
+		const std::string &zkSNARK
+	) {
+		PourTransaction pourtx;
+
+		pourtx.version = 1;
+		pourtx.publicOldValue.resize(8);
+		pourtx.publicNewValue.resize(8);
+		convertIntToBytesVector(vpub_old, pourtx.publicOldValue);
+    	convertIntToBytesVector(vpub_new, pourtx.publicNewValue);
+    	pourtx.serialNumber_1 = serials[0];
+    	pourtx.serialNumber_2 = serials[1];
+    	{
+    		CoinCommitment cm;
+    		cm.commitmentValue = commitments[0];
+    		pourtx.cm_1 = cm;
+    	}
+    	{
+    		CoinCommitment cm;
+    		cm.commitmentValue = commitments[1];
+    		pourtx.cm_2 = cm;
+    	}
+    	pourtx.MAC_1 = macs[0];
+    	pourtx.MAC_2 = macs[1];
+    	pourtx.zkSNARK = zkSNARK;
+
+    	return pourtx.verify(params, pubkeyHash, rt);
+	}
+};
+
+
+}
+
+#endif /* POURPROVER_H_ */

libzerocash/PourTransaction.cpp

@@ -354,7 +354,7 @@ void PourTransaction::init(uint16_t version_num,
 }
 
 bool PourTransaction::verify(ZerocashParams& params,
-                             std::vector<unsigned char> &pubkeyHash,
+                             const std::vector<unsigned char> &pubkeyHash,
                              const MerkleRootType &merkleRoot) const
 {
 	if(this->version == 0){

libzerocash/PourTransaction.h

@@ -18,6 +18,9 @@
 #include "PourInput.h"
 #include "PourOutput.h"
 #include <stdexcept>
+#include <bitset>
+
+#include <boost/array.hpp>
 
 typedef std::vector<unsigned char> CoinCommitmentValue;
 
@@ -26,6 +29,7 @@ namespace libzerocash {
 /***************************** Pour transaction ******************************/
 
 class PourTransaction {
+friend class PourProver;
 public:
     PourTransaction();
     PourTransaction(ZerocashParams& params,
@@ -104,7 +108,7 @@ class PourTransaction {
      * @return ture if correct, false otherwise.
      */
     bool verify(ZerocashParams& params,
-                std::vector<unsigned char> &pubkeyHash,
+                const std::vector<unsigned char> &pubkeyHash,
                 const MerkleRootType &merkleRoot) const;
 
     const std::vector<unsigned char>& getSpentSerial1() const;
@@ -130,6 +134,48 @@ class PourTransaction {
 
     uint64_t getPublicValueOut() const;
 
+    std::string unpack(boost::array<std::vector<unsigned char>, 2>& serials,
+                boost::array<std::vector<unsigned char>, 2>& commitments,
+                boost::array<std::vector<unsigned char>, 2>& macs,
+                boost::array<std::string, 2>& ciphertexts
+               ) const {
+        serials[0] = this->serialNumber_1;
+        serials[1] = this->serialNumber_2;
+        commitments[0] = this->cm_1.getCommitmentValue();
+        commitments[1] = this->cm_2.getCommitmentValue();
+        macs[0] = this->MAC_1;
+        macs[1] = this->MAC_2;
+        ciphertexts[0] = this->ciphertext_1;
+        ciphertexts[1] = this->ciphertext_2;
+
+        return this->zkSNARK;
+    }
+
+    // just hashes a few fields to see if integrity is correct.
+    // useful for debugging since there's such bad error handling
+    // currently
+    void debug_print() {
+        #define DEBUG_PRINT_POUR_FIELD(X, NAME) {\
+            std::hash<std::string> h; \
+            std::cout << NAME << ": " << h(std::string(X.begin(), X.end())) << std::endl;\
+        }
+
+        DEBUG_PRINT_POUR_FIELD(publicOldValue, "publicOldValue");
+        DEBUG_PRINT_POUR_FIELD(publicNewValue, "publicNewValue");
+        DEBUG_PRINT_POUR_FIELD(serialNumber_1, "serialNumber_1");
+        DEBUG_PRINT_POUR_FIELD(serialNumber_2, "serialNumber_2");
+        {
+            auto v = cm_1.getCommitmentValue();
+            DEBUG_PRINT_POUR_FIELD(v, "cm_1");
+        }
+        {
+            auto v = cm_2.getCommitmentValue();
+            DEBUG_PRINT_POUR_FIELD(v, "cm_2");
+        }
+        DEBUG_PRINT_POUR_FIELD(MAC_1, "MAC_1");
+        DEBUG_PRINT_POUR_FIELD(MAC_2, "MAC_2");
+
+    }
 
 private: