Osprey

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Author and Contract

osprey is developed by alittlehorse,syheliel,cx19981114,Zirui Hu and is released under the MIT license.

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NOTE:this project is a Big data PaaS(Processing as a Server) trading platform based on zero-knowledge proof and blockchain with the protection of data privacy and functional privacy. I modified source code of libsnark developed by the SCIPR Lab and contributors to archieve the tinyram_snark module.

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Overview

This platform implements pp-zkSNARK schemes(Groth16), which are a cryptographic method for proving/verifying, in zero knowledge, the integrity of computations.
This platform implements fair-swap using smart contract.
This platform implements network transmission between buyer and provider.

A computation can be expressed as an NP statement in form:
"The Tinyram program foo, when executed, returns answer 0 if given the input bar and some additional input qux."

A prover who knows the witness for the NP statement (i.e., a satisfying input/assignment) can produce a short proof attesting to the truth of the NP statement. This proof can be verified by anyone, and offers the following properties.

• Zero knowledge: the verifier learns nothing from the proof beside the truth of the statement (i.e., the value qux, in the above examples, remains secret).
• Succinctness: the proof is short and easy to verify.
• Non-interactivity: the proof is a string (i.e. it does not require back-and-forth interaction between the prover and the verifier).
• Soundness: the proof is computationally sound (i.e., it is infeasible to fake a proof of a false NP statement). Such a proof system is also called an argument.
• Proof of knowledge: the proof attests not just that the NP statement is true, but also that the prover knows why (e.g., knows a valid qux).

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A prover who knows the witness for the NP statement (i.e., a satisfying input/assignment) can produce a short proof attesting to the truth of the NP statement. This proof can be verified by anyone, and offers the following properties.

• Zero knowledge: the verifier learns nothing from the proof beside the truth of the statement (i.e., the value qux, in the above examples, remains secret).
• Succinctness: the proof is short and easy to verify.
• Non-interactivity: the proof is a string (i.e. it does not require back-and-forth interaction between the prover and the verifier).
• Soundness: the proof is computationally sound (i.e., it is infeasible to fake a proof of a false NP statement). Such a proof system is also called an argument.
• Proof of knowledge: the proof attests not just that the NP statement is true, but also that the prover knows why (e.g., knows a valid qux).

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Security

This code is a research-quality proof of concept, and has not yet undergone extensive review or testing. It is thus not suitable, as is, for use in critical or production systems

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Build instructions

Dependencies

The libsnark library relies on the following:

• C++ build environment
• CMake build infrastructure
• GMP for certain bit-integer arithmetic
• libprocps for reporting memory usage
• Boost1.75

$ wget https://boostorg.jfrog.io/artifactory/main/release/1.75.0/source/boost_1_75_0.tar.bz2 && tar -xvf ./boost_1_75_0.tar.bz2 
$ cd ./boost_1_75_0 && ./bootstrap.sh && sudo ./b2 install

So far we have tested these only on Linux. On Debian 10 (buster), Ubuntu 18.04 LTS, Ubuntu 20.04 LTS:

  $ sudo apt install build-essential cmake git libgmp3-dev libprocps-dev python3-markdown libboost-program-options-dev libssl-dev python3 pkg-config python3-dev libevent-dev
  $ sudo apt install libjsoncpp-dev uuid-dev openssl libssl-dev zlib1g-dev # for drogon

after cloning, you should download submodule:

git submodule update --init --recursive

Building

Create the Makefile:

$ mkdir build && cd build && cmake ..

If you want to build one specific target, for example, platform_server:

cmake --build . --target platform_server

then, to compile the library, tests, and profiling harness, run this within the build directory:

$ make

To compile and run the tests for this library, run:

$ make check

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References

• libsnark developed by SCIPR: https://github.com/scipr-lab/libsnark
• [BCTV14a] Succinct non-interactive zero knowledge for a von Neumann architecture , Eli Ben-Sasson, Alessandro Chiesa, Eran Tromer, Madars Virza, USENIX Security 2014
• [ate-pairing] High-Speed Software Implementation of the Optimal Ate Pairing over Barreto-Naehrig Curves , MITSUNARI Shigeo, TERUYA Tadanori
• [Groth16] On the Size of Pairing-based Non-interactive Arguments , Jens Groth, EUROCRYPT 2016