GnuTLS is a secure communications library implementing the SSL, TLS, and DTLS protocols and technologies around them. It provides a simple C language application programming interface (API) to access the secure communications protocols, as well as APIs to parse and write X.509, PKCS #12, OpenPGP, and other required structures. It is intended to be portable and efficient with a focus on security and interoperability.
PeaZip is a cross-platform file archiver utility that provides a unified portable GUI for many open source technologies like 7-Zip, FreeArc, PAQ, UPX, etc. Creates 7Z, ARC, BZ2, GZ, *PAQ, PEA, QUAD/BALZ, TAR, UPX, WIM, XZ, and ZIP files. It extracts more than 150 archive types: ACE, ARJ, CAB, DMG, ISO, LHA, RAR, UDF, ZIPX, and more. Features of PeaZip include extracting, creating, and converting multiple archives at once, creating self-extracting archives, split/join files, strong encryption with two factor authentication, an encrypted password manager, secure deletion, find duplicate files, calculate hashes, and export job definitions as scripts.
RFC 2015 defines a proposed Internet standard for sending PGP-encrypted email. This PGP/MIME has been incorporated into several MUAs such as Mutt and (with the AEGYPTEN project) KMail. However, a lot of email clients still don't support it. pgp-mime-handler can decrypt/verify such messages via a pipe, so it can be used as an email filter in many programs or scripts.
pyOpenSSL is a Python wrapper for a subset of OpenSSL's functionality, featuring an advanced error management system, connection objects that wrap socket methods, and flexible context objects. Also included is a rudimentary crypto module that can be used to create and verify certificates (X509 objects).
JHBCI is JCA/JCE cryptographic service provider for Java. It is useful for building HBCI home banking applications (clients and servers). JHBCI implements all relevant "RDH" crypto algorithms for the German Homebanking Standard HBCI Version 2.2, such as DES, RSA, ISO9796-1:1991-Signature, and RIPEMD160-MessageDigest.
OpenXAdES enables people to work with legally-binding digital signatures (primarily giving and verifying them). Legislation often defines a set of requirements that legal digital signature technologies and infrastructures must be compliant with, and OpenXAdES aims at meeting many, if not all, such requirements from different legislations.
MpNT is a multi-precision number theory library that provides a base for building cryptographic applications. It may also be used in any other domain where efficient large number computations are required. The library supports integer, modular, and floating point arithmetic with practically unlimited precision. It is both speed efficient and highly portable without disregarding code structure and clarity.