CPR is a toolbox for specifying, simulating, and attacking proof-of-work consensus protocols. In this repository you find
- protocol specifications for Bitcoin, Ethereum PoW, and others,
- implementations of known attacks against these protocols,
- a simulator that executes the specified protocols and attacks in a virtual environment,
- tooling for automatic attack-search with MDPs and
- tooling for automatic attack-search with reinforcement learning (RL) and
- evaluation scripts and notebooks for the above.
I'm working on a website with more details.
- CPR was inspired by my previous work on HotPoW and Parallel Proof-of-Work
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$\mathcal B_k$ . (Network Simulation) [code] [preprint] [AFT'22 paper] - I've applied CPR to analyze the Tailstorm consensus and cryptocurrency. (Network Simulation, RL) [preprint] [AFT'23 paper]
- I've applied CPR to analyze a few DAG-based proof-of-work protocol proposals. (RL) [preprint]
- I've applied CPR to analyze GhostDAG and other DAG-based proof-of-work protocols (MDP) [early] [pull-request] [preprint]
CPR provides an OpenAI Gym environment for attack search with Python RL frameworks. If you meet the following requirements, you can install it from PyPI.
- Unix-like operating system with x86_64 support
- CPython, version >= 3.9
pip install cpr-gymIf this worked, you are ready to go. The following snippet simulates 2016 steps of honest behaviour in Nakamoto consensus.
import gym
import cpr_gym
env = gym.make("cpr-nakamoto-v0", episode_len = 2016)
obs = env.reset()
done = False
while not done:
action = env.policy(obs, "honest")
obs, rew, done, info = env.step(action)The protocol specifications and simulator are OCaml programs. Also most
parts of the Gym environment are written in OCaml. The Python module
cpr_gym loads the OCaml code from a pre-compiled shared object named
cpr_gym_engine.so. In order to install the package from source, you
have to build this shared object and hence have the OCaml toolchain
installed.
Opam is the OCaml package manager. It's a bit like Python's pip or
Javascript's npm. We use it do download and install our OCaml
dependencies and to manage different versions of the OCaml compiler.
Make sure that a recent version (>= 2.0) is installed on your system.
Follow these instructions.
Then use make setup to get compiler and dependencies setup in the
current working directory under _opam. Later, e.g. when dependencies
change, run make dependencies to update the toolchain. If you ever
suspect that the OCaml dependencies are broken, and you do not know how
to fix it, delete the _opam directory and run make setup again.
Dune is an OCaml build system. We use it to build executables and
shared objects, and to run tests. You do not have to interact with dune
directly. Just run make build to test whether the OCaml build works.
Now, installing cpr_gym as editable Python package should work. Try
pip install -e . and follow the short Python example above. If it
works, you're ready to go.
import cpr_gym tries to detect editable installs. If so,
cpr_gym_engine.so is loaded from the OCaml build directory
(./_build). You can rebuild the DLL with make build.
It might be useful to install all Python development dependencies with
pip install -r requirements.txt. Afterwards, you can run the full test
suite, OCaml and Python, with make test.