Awesome

Blockchain Commons UR Library

by Wolf McNally and Christopher Allen

• <img src="https://github.com/BlockchainCommons/crypto-commons/blob/master/images/logos/crypto-commons-super-simple.png" width=16 valign="bottom">   part of the crypto commons technology family

The Blockchain Commons UR Library is a UR Reference Implementation in C++.

Introduction

URs ("Uniform Resources") are a method for encoding structured binary data for transport in URIs and QR Codes. They are described in BCR-2020-005.

There also another reference implementation in Swift: URKit, and a demo app that uses it to display and read multi-part animated QR codes: URDemo.

Installation instructions

This sequence also runs the module's unit tests.

MacOS

$ ./configure
$ make check
$ sudo make install

Linux

Make sure you have llvm/clang, libc++ and libc++abi installed. All of them with a minimum recommended version 10.

Ubuntu and Debian

$ sudo apt-get install make

$ wget https://apt.llvm.org/llvm.sh
$ chmod +x llvm.sh
$ sudo ./llvm.sh 10  # version 10

$ sudo apt-get install libc++-10-dev libc++abi-10-dev

$ export CC="clang-10" && export CXX="clang++-10" && ./configure
$ make check
$ sudo make install

Usage Instructions

1. Link against libbc-ur.a.
2. Include the umbrella header in your code:

#include <bc-ur/bc-ur.hpp>

The highest-level APIs are found in ur-encoder.hpp and ur-decoder.hpp.

Notes for Maintainers

Before accepting a PR that can affect build or unit tests, make sure the following sequence of commands succeeds:

$ ./configure
$ make lint
$ make distcheck
$ make distclean

make lint uses Cppcheck to perform static analysis on the code. All PRs should pass with no warnings.

make distcheck builds a distribution tarball, unpacks it, then configures, builds, and runs unit tests from it, then performs an install and uninstall from a non-system directory and makes sure the uninstall leaves it clean. make distclean removes all known byproduct files, and unless you've added files of your own, should leave the directory in a state that could be tarballed for distribution. After a make distclean you'll have to run ./configure again.

Status - Late Alpha

Blockchain Commons UR Library is currently under active development and in the late alpha testing phase. It should not be used for production tasks until it has had further testing and auditing.

Origin, Authors, Copyright & Licenses

Unless otherwise noted (either in this /README.md or in the file's header comments) the contents of this repository are Copyright © 2020 by Blockchain Commons, LLC, and are licensed under the spdx:BSD-2-Clause Plus Patent License.

The table below establishes provenance (repository of origin, permalink, and commit id) for each source file in this repository. Contributors to these files are listed in the commit history for each file, first in this repo, then in the repo of their origin.

In most cases, the authors, copyright, and license for each file reside in comments in the source. When it does not we have attempted to attribute it accurately below.

Dependencies

• autotools - Gnu Build System from Free Software Foundation (intro).

Subsequent Usage

These are adaptations, conversions, and wrappers that make bc-ur available for other languages:

• foundation-ur-py Python implementation by Foundation Devices

• Hummingbird - Java implementation by Sparrow Wallet

• URKit - Swift implementation by Blockchain Commons is another reference implementation of URs (not directly derived from bc-ur though)

• bc-ur-java - Java wrapper by Blockchain Commons

• ur-rs - Rust implementation by Dominik Spicher

• bc-ur - Javascript/Typescript implementation by NGRAVE

Financial Support

Blockchain Commons Crypto Base is a project of Blockchain Commons. We are proudly a "not-for-profit" social benefit corporation committed to open source & open development. Our work is funded entirely by donations and collaborative partnerships with people like you. Every contribution will be spent on building open tools, technologies, and techniques that sustain and advance blockchain and internet security infrastructure and promote an open web.

To financially support further development of Blockchain Commons Crypto Base and other projects, please consider becoming a Patron of Blockchain Commons through ongoing monthly patronage as a GitHub Sponsor. You can also support Blockchain Commons with bitcoins at our BTCPay Server.

Contributing

We encourage public contributions through issues and pull-requests! Please review CONTRIBUTING.md for details on our development process. All contributions to this repository require a GPG signed Contributor License Agreement.

Discussions

The best place to talk about Blockchain Commons and its projects is in our GitHub Discussions areas.

Gordian Developer Community. For standards and open-source developers who want to talk about interoperable wallet specifications, please use the Discussions area of the Gordian Developer Community repo. This is where you talk about Gordian specifications such as Gordian Envelope, bc-shamir, Sharded Secret Key Reconstruction, and bc-ur as well as the larger Gordian Architecture, its Principles of independence, privacy, resilience, and openness, and its macro-architectural ideas such as functional partition (including airgapping, the original name of this community).

Blockchain Commons Discussions. For developers, interns, and patrons of Blockchain Commons, please use the discussions area of the Community repo to talk about general Blockchain Commons issues, the intern program, or topics other than those covered by the Gordian Developer Community or the Gordian User Community.

Other Questions & Problems

As an open-source, open-development community, Blockchain Commons does not have the resources to provide direct support of our projects. Please consider the discussions area as a locale where you might get answers to questions. Alternatively, please use this repository's issues feature. Unfortunately, we can not make any promises on response time.

If your company requires support to use our projects, please feel free to contact us directly about options. We may be able to offer you a contract for support from one of our contributors, or we might be able to point you to another entity who can offer the contractual support that you need.

Credits

The following people directly contributed to this repository. You can add your name here by getting involved — the first step is to learn how to contribute from our CONTRIBUTING.md documentation.

Responsible Disclosure

We want to keep all our software safe for everyone. If you have discovered a security vulnerability, we appreciate your help in disclosing it to us in a responsible manner. We are unfortunately not able to offer bug bounties at this time.

We do ask that you offer us good faith and use best efforts not to leak information or harm any user, their data, or our developer community. Please give us a reasonable amount of time to fix the issue before you publish it. Do not defraud our users or us in the process of discovery. We promise not to bring legal action against researchers who point out a problem provided they do their best to follow the these guidelines.

Reporting a Vulnerability

Please report suspected security vulnerabilities in private via email to ChristopherA@BlockchainCommons.com (do not use this email for support). Please do NOT create publicly viewable issues for suspected security vulnerabilities.

The following keys may be used to communicate sensitive information to developers:

You can import a key by running the following command with that individual’s fingerprint: gpg --recv-keys "<fingerprint>" Ensure that you put quotes around fingerprints that contain spaces.

Version History

0.3.0, 19/01/2020

• Added support for floating point encoding and decoding to embedded CBORLite.

0.2.0, 19/04/2020

• Fixed ByteWords wordlist alphabetization error.

0.1.0, 08/09/2020

• Initial testing release.