Bouncy Castle (cryptography)

History

Bouncy Castle started when two colleagues were tired of having to re-invent a set of cryptography libraries each time they changed jobs working in server-side JavaSE. One of the developers was active in JavaME (J2ME at that time) development as a hobby and a design consideration was to include the greatest range of Java VMs for the library, including those on J2ME.

This design consideration led to the architecture that exists in Bouncy Castle.

Some key properties of the project are:

On 18 October 2013, a not-for-profit association, the Legion of the Bouncy Castle Inc. was established in the state of Victoria, Australia, by the core developers and others to take ownership of the project and support the ongoing development of the APIs. The association was recognised as an Australian charity with a purpose of advancement in education and a purpose that is beneficial to the community by the Australian Charities and Not-For-Profits Commission on 7 November 2013. The association was authorised to fundraise to support its purposes on 29 November 2013 by Consumer Affairs Victoria.

Architecture

The Bouncy Castle architecture consists of two main components that support the base cryptographic capabilities. These are known as the 'light-weight' API, and the Java Cryptography Extension (JCE) provider. Further components built upon the JCE provider support additional functionality, such as PGP support, S/MIME, etc.

The low-level, or 'light-weight', API is a set of APIs that implement all the underlying cryptographic algorithms. The APIs were designed to be simple enough to use if needed, but provided the basic building blocks for the JCE provider. The intent is to use the low-level API in memory constrained devices (JavaME) or when easy access to the JCE libraries is not possible (such as distribution in an applet). As the light-weight API is just Java code, the Java virtual machine (JVM) does not impose any restrictions on the operation of the code, and at early times of the Bouncy Castle history it was the only way to develop strong cryptography that was not crippled by the Jurisdiction Policy files that prevented JCE providers from performing "strong" encryption.

The JCE-compatible provider is built upon the low-level APIs. As such, the source code for the JCE provider is an example of how to implement many of the "common" crypto problems using the low-level API. Many projects have been built using the JCE provider, including an Open Source Certificate Authority EJBCA.

Certified releases

The C# and Java releases now have FIPS 140-2 Level 1 certified streams as well. These differ from the regular releases in that, while the modules are designed in a similar fashion to the regular releases, the low-level APIs are quite different – largely to support the enforcement of controls that FIPS requires on algorithm use. In the case of the JCE level of the Java API the provider is still largely a drop replacement for the regular release. The first FIPS certified releases were made available in November of 2016, with the Java version being assigned certification number 2768 and the C# version being assigned certification number 2792.

Spongy Castle

The Android operating system, as of early 2014, includes a customized version of Bouncy Castle. Due to class name conflicts, this prevents Android applications from including and using the official release of Bouncy Castle as-is. A third-party project called Spongy Castle distributes a renamed version of the library to work around this issue.