BLCred

implement of paper BLCred: User-Centric Decentralized Identities with Anonymity and Accountability atop Distributed Ledgers

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Offline version

An half on-chain implement of BLCred system based on python. blockchain is only responsible for recording credentials.

Prerequisites and setup:

(All available at Pypi)

• bplib
• petlib

export OPENSSL_CONF=/usr/local/ssl/openssl.cnf
sudo apt-get install libssl-dev
pip3 install petlib
pip3 install bplib

All the algorithm has been implemented as Lib*.py in folder /BLCred_offline/lib/

BLCred.py will call them and complete a typical usage process.

to run the project

cd BLCred_offline
python3 BLCred.py

Online version

An completely on-chain implement of BLCred system with HyperlederFabric based on go and nodejs

Prerequisites and setup:

• go 1.13.4
• nodejs 8.10.0 & npm 3.5.2
• docker 20.10.0
• Fabric 2.2.0

You can find a basic tutorials on environment configuration here: Getting Started

we use a third party bilinearity lib instead of bn256 of go language, install it with

go get github.com/drbh/zkproofs/go-ethereum/crypto/bn256

to run the project

cd BLCred_online/app
./startFabric.sh
./testBLCred.sh
./stopFabric.sh

startFabric.sh will start a Fabric network and install the chaincode, then testBLCred.sh will execute the NodeJS scripts: enrollAdmin.js, registerUser.js, and invoke.js will execute the chaincode functions.

If all goes well, it will print the time spent by each chaincode function