The Bouncy Castle Crypto APIs consist of the following:

. A lightweight cryptography API in Java.
. A provider for the JCE and JCA.
. A clean room implementation of the JCE 1.2.1.
. A library for reading and writing encoded ASN.1 objects.
. Lightweight APIs for TLS (RFC 2246, RFC 4346) and DTLS (RFC 4347).
. Generators for Version 1 and Version 3 X.509 certificates, Version 2 CRLs,
  and PKCS12 files.
. Generators for Version 2 X.509 attribute certificates.
. Generators/Processors for S/MIME and CMS (PKCS7/RFC 3852).
. Generators/Processors for OCSP (RFC 2560).
. Generators/Processors for TSP (RFC 3161 & RFC 5544).
. Generators/Processors for CMP and CRMF (RFC 4210 & RFC 4211).
. Generators/Processors for OpenPGP (RFC 2440).
. Generators/Processors for Extended Access Control (EAC).
. Generators/Processors for Data Validation and Certification Server (DVCS) -
  RFC 3029.
. Generators/Processors for DNS-based Authentication of Named Entities (DANE).
. A signed jar version suitable for JDK 1.4-1.8 and the Sun JCE.

It's distributed under a modified X license.

WWW: http://www.bouncycastle.org/