LedgerMaze: An Efficient Privacy-Preserving NIZK Scheme over Account-Model Blockchain

Specifications

• OS: Linux x64

• Language: C++

• Requires: OpenSSL libsecp256k1

• The default elliptic curve is "NID_X9_62_prime256v1"

Installation

The current implementation is based on OpenSSL library. See the installment instructions of OpenSSL as below:

1. Download openssl-master.zip

2. make a directory "openssl" to save the source codes of MIRACL

    mkdir openssl
    mv openssl-master.zip /openssl

3. unzip it

4. install openssl on your machine

    ./config --prefix=/usr/local/ssl shared
    make 
    sudo make install

5. install libsecp256k1 on your machine

   cd ./depends/oneoutofnproofs/secp256k1
    ./autogen.sh
    ./configure
    make 

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Code Structure of LedgerMaze_openssl

/depends: depends module

• /common: common module

  • global.hpp: generate global parameters
  • print.hpp: print split line for demo use
  • hash.hpp: case-tailored hash functions based on SHA2
  • routines.hpp: related routine algorithms

• /twisted_elgamal: ISE module

  • twisted_elgamal.hpp: twisted ElGamal ISE and PKE
  • calculate_dlog.hpp: discrete logarithm searching algorithm

• /nizk: NIZK module, obtained by applying Fiat-Shamir transform to Sigma-protocols

  • nizk_plaintext_equality.hpp: NIZKPoK for twisted ElGamal plaintext equality
  • nizk_plaintext_knowledge.hpp: NIZKPoK for twisted ElGamal plaintext and randomness knowledge
  • nizk_dlog_equality.hpp: NIZKPoK for discrete logarithm equality

• /bulletproofs: Bulletproofs module

  • basic_bulletproof.hpp: the basic bulletproofs
  • log_bulletproof.hpp: the logarithmic size bulletproofs
  • aggregate_bulletproof.hpp: the aggregating logarithmic size bulletproofs
  • innerproduct_proof.hpp: the inner product argument (used by Bulletproof to shrink the proof size)

• /gadgets: Gadget module

  • gadgets.hpp: two useful gadgets for proving encrypted values lie in the right range

• /oneoutofnproofs: oneoutofnproofs module

/test: all test files

/bench: all bench files

/backend: all backend files for ledgermaze system

Testing

In test\test_ledgermaze, there is a system test and it can open a backend for our LedgerMaze

  $ ./make_twisted_elgamal.sh
  $ ./test_enc # tests the twisted ElGamal ISE and PKE

You can find the bash files in /previous and do the unit test for any module

To compile and test the LedgerMaze system, do the following:

  $ mkdir build && cd build
  $ cmake ..
  $ make
  $ ./test_ledgermaze