MatrixSSL is an embedded SSL and TLS implementation designed for small footprint devices and applications requiring low overhead per connection. The library is less than 50Kb on disk with cipher suites. It includes client and server support through TLS 1.2, mutual authentication, session resumption, and implementations of RSA, ECC, AES, 3DES, ARC4, SHA2, SHA1, and MD5. The source is well documented and contains portability layers for additional operating systems, cipher suites, and cryptography providers.
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.
CyberFusion is a system that provides secure file transfer across a LAN, a WAN, and the Internet. It offers encryption and security, reliability and guaranteed delivery, management and automation, audit and control. It offers cost-saving migration from competitor products such as Connect:Direct which is supported with useful tools. It may be used as part of a VPN, ERP, EAI, or ETL software solution for secure file transfers as well as in disaster recovery, data archive, and backup and restore operations.
NetCrypto is a library of functions and a framework to interface with crypto algorithms provided by the calling application, built-in, or provided through shared libraries. It was developed with some features from OpenSSL in mind and with some inspiration from OpenSSL's EVP layer and ENGINE framework.
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.
Password Manager Daemon serves clients data via a Unix domain socket or over a remote TLS connection. The data is stored in an (optionally) encrypted XML file, and the client must provide the key to modify it. It has the option to use gpg-agent for key management (including smartcards). It is multi-threaded, allowing more than one client to be connected at the same time. Key retrieval may be done via a key file or a pinentry program. A key cache is used, so a client won't need to enter a passphrase each time one is required. It is very configurable. Libpwmd is also available as a separate project and is a library making it easy for applications to use Pwmd.
tkpg is a program that provides a GUI front end to Philip Zimmermann's Pretty Good Privacy (PGP) public-key encryption system and also the GNU Privacy Guard (GnuPG/gpg) implementation. It utilizes the Clipboard Selection heavily to ease moving pgp-processed text both to and from any of your applications (such as mail reader, news reader, and editor). This removes the need to select the output text by hand or by typing in a filename, since it is usually placed in the Selection automatically for you.
John the Ripper is a fast password cracker, currently available for many flavors of Unix, Windows, DOS, BeOS, and OpenVMS. Its primary purpose is to detect weak Unix passwords. It supports several crypt(3) password hash types commonly found on Unix systems, as well as Windows LM hashes. On top of this, lots of other hashes and ciphers are added in the community-enhanced version (-jumbo), and some are added in John the Ripper Pro.