Dar is a shell command that makes backup of a directory tree and files. Its features include splitting archives over several files, DVD, CD, ZIP, or floppies, compression, full or differential backups, strong encryption, proper saving and restoration of hard links, extended attributes, file forks, Door inodes, and sparse files, remote backup using pipes and external commands (such as ssh), and rearrangement of the "slices" of an existing archive. It can run commands between slices, before and after saving some defined files or directories (for a proper database backup, for example), and quickly retrieve individual files from differential and full backups. Several external GUIs exist as alternatives to its CLI interface, like kdar, DarGUI, SaraB, etc.
OpenVPN is a robust and highly configurable VPN (Virtual Private Network) daemon which can be used to securely link two or more private networks using an encrypted tunnel over the Internet. OpenVPN's principal strengths include wide cross-platform portability, excellent stability, support for dynamic IP addresses and NAT, adaptive link compression, single TCP/UDP port usage, a modular design that offloads most crypto tasks to the OpenSSL library, and relatively easy installation that in most cases doesn't require a special kernel module.
Botan is a crypto library written in C++. It provides a variety of cryptographic algorithms, including common ones such as AES, MD5, SHA, HMAC, RSA, Diffie-Hellman, DSA, and ECDSA, as well as many others that are more obscure or specialized. It also offers SSL/TLS (client and server), X.509v3 certificates and CRLs, and PKCS #10 certificate requests. A message processing system that uses a filter/pipeline metaphor allows for many common cryptographic tasks to be completed with just a few lines of code. Assembly and SIMD optimizations for common CPUs offers speedups for critical algorithms like AES and SHA-1.
XCA is an interface for managing RSA and DSA keys, certificates, certificate signing requests, revocation lists and templates. It uses the OpenSSL and Qt4 libraries. Certificates and requests can be created and signed and many x509v3 extensions can be added. XCA supports multiple root and intermediate Certificate authorities. The CAs can be used to create CRLs and extend certificates. The following file-formats are supported: PEM, DER, PKCS#7, PKCS#8, PKCS#10, PKCS#12, and SPKAC.
Open Transactions is a solid, easy-to-use, financial crypto and digital cash library, including an API, server, and test client. It features anonymous numbered accounts, untraceable digital cash, triple-signed receipts, basket currencies, and signed XML contracts. It also supports cheques, invoices, payment plans, markets with trades, and other instruments. It uses OpenSSL and Lucre blinded tokens.
PHPCoder is a Web-based frontend to the Turck MMCache encoding functions, which are similar to the Zend Encoder product. PHPCoder enables you to encode your PHP scripts and applications into non-reversible bytecode, thus preventing users of your programs from viewing or altering the source code while having full functionality. Another excellent use for PHPCoder is to encode your applications PHP configuration files, that way someone viewing your source code does not see your databae login and password information. It also allows you to set restrictions on the encoded scripts, you can lock a script to a particular server IP address, server host name, visitor IP, or even place a time limit on the script so it will expire after a configurable amount of time. You specify Text, HTML, or PHP code that should be prepended and appended to each file before it is encoded, allowing you to easily and securely implement your own licensing scheme.
Moneychanger is a simple client GUI built on top of Open Transactions, a financial crypto library. Moneychanger can be used to create pseudonyms, issue currencies, open accounts, withdraw and deposit cash (untraceable digital cash), write and deposit cheques, trade on markets, and much, much more.
Zebedee is a simple program to establish an encrypted, compressed tunnel for TCP/IP or UDP data transfer between two systems. This allows traffic such as telnet, FTP, and X to be protected from snooping as well as potentially gaining performance over low-bandwidth networks from compression.
The Shrew Soft VPN Client for Unix is a free IPsec Client for FreeBSD, NetBSD, and Linux based operating systems. It can be used to communicate with systems running ipsec-tools. The Unix client utilizes the IPsec kernel support included with the operating system, and comes with the complete Internet Key Exchange daemon and client front end application source code. A Windows version is also available.