Import ZeroCoin adapted sources

[novacoin.git] / src / zerocoin / CoinSpend.h

diff --git a/src/zerocoin/CoinSpend.h b/src/zerocoin/CoinSpend.h
new file mode 100644 (file)
index 0000000..c8d20b9
--- /dev/null
+++ b/src/zerocoin/CoinSpend.h
@@ -0,0 +1,107 @@
+/**
+ * @file       CoinSpend.h
+ *
+ * @brief      CoinSpend class for the Zerocoin library.
+ *
+ * @author     Ian Miers, Christina Garman and Matthew Green
+ * @date       June 2013
+ *
+ * @copyright  Copyright 2013 Ian Miers, Christina Garman and Matthew Green
+ * @license    This project is released under the MIT license.
+ **/
+
+#ifndef COINSPEND_H_
+#define COINSPEND_H_
+
+#include "Params.h"
+#include "Coin.h"
+#include "Commitment.h"
+#include "../bignum.h"
+#include "Accumulator.h"
+#include "AccumulatorProofOfKnowledge.h"
+#include "SerialNumberSignatureOfKnowledge.h"
+#include "SpendMetaData.h"
+#include "../serialize.h"
+
+namespace libzerocoin {
+
+/** The complete proof needed to spend a zerocoin.
+ * Composes together a proof that a coin is accumulated
+ * and that it has a given serial number.
+ */
+class CoinSpend {
+public:
+       template<typename Stream>
+       CoinSpend(const Params* p,  Stream& strm):denomination(ZQ_LOVELACE),
+               accumulatorPoK(&p->accumulatorParams),
+               serialNumberSoK(p),
+               commitmentPoK(&p->serialNumberSoKCommitmentGroup, &p->accumulatorParams.accumulatorPoKCommitmentGroup) {
+               strm >> *this;
+       }
+       /**Generates a proof spending a zerocoin.
+        *
+        * To use this, provide an unspent PrivateCoin, the latest Accumulator
+        * (e.g from the most recent Bitcoin block) containing the public part
+        * of the coin, a witness to that, and whatever medeta data is needed.
+        *
+        * Once constructed, this proof can be serialized and sent.
+        * It is validated simply be calling validate.
+        * @warning Validation only checks that the proof is correct
+        * @warning for the specified values in this class. These values must be validated
+        *  Clients ought to check that
+        * 1) params is the right params
+        * 2) the accumulator actually is in some block
+        * 3) that the serial number is unspent
+        * 4) that the transaction
+        *
+        * @param p cryptographic parameters
+        * @param coin The coin to be spend
+        * @param a The current accumulator containing the coin
+        * @param witness The witness showing that the accumulator contains the coin
+        * @param m arbitrary meta data related to the spend that might be needed by Bitcoin
+        *                      (i.e. the transaction hash)
+        * @throw ZerocoinException if the process fails
+        */
+       CoinSpend(const Params* p, const PrivateCoin& coin, Accumulator& a, const AccumulatorWitness& witness, const SpendMetaData& m);
+
+       /** Returns the serial number of the coin spend by this proof.
+        *
+        * @return the coin's serial number
+        */
+       const Bignum& getCoinSerialNumber();
+
+       /**Gets the denomination of the coin spent in this proof.
+        *
+        * @return the denomination
+        */
+       const CoinDenomination getDenomination();
+
+       bool Verify(const Accumulator& a, const SpendMetaData &metaData) const;
+
+       IMPLEMENT_SERIALIZE
+       (
+           READWRITE(denomination);
+           READWRITE(accCommitmentToCoinValue);
+           READWRITE(serialCommitmentToCoinValue);
+           READWRITE(coinSerialNumber);
+           READWRITE(accumulatorPoK);
+           READWRITE(serialNumberSoK);
+           READWRITE(commitmentPoK);
+       )
+
+private:
+       const Params *params;
+       const uint256 signatureHash(const SpendMetaData &m) const;
+       // Denomination is stored as an INT because storing
+       // and enum raises amigiuities in the serialize code //FIXME if possible
+       int denomination;
+       Bignum accCommitmentToCoinValue;
+       Bignum serialCommitmentToCoinValue;
+       Bignum coinSerialNumber;
+       AccumulatorProofOfKnowledge accumulatorPoK;
+       SerialNumberSignatureOfKnowledge serialNumberSoK;
+       CommitmentProofOfKnowledge commitmentPoK;
+};
+
+} /* namespace libzerocoin */
+#endif /* COINSPEND_H_ */