Tools and Open Source
- CryptTool Wikipedia
- CrypTool 1 (CT1) was released in 1998 and runs under Windows and has two successors: CT2 and JCT.
- CrypTool 2 (CT2) supports visual programming and execution of cascades of cryptographic procedures.
CT2 contains a large number of cryptanalysis methods and also runs under Windows.
- JCrypTool (JCT) is platform-independent and runs under Linux, Mac and Windows.
One focus are post-quantum (signature) algorithms.
- CrypTool-Online (CTO) was released in spring 2009. Runs in a browser
- gnupg.org - GPG
- gpg4win.org - GPG for Windows - email and file encryption
- Sign files or folders from Windows Explorer with GpgEX or Kleopatra
- Comes with Microsoft Outlook plugin GpgOL to sign and encrypt emails and attachments. Verification and decrytion directly in Outlook.
- Executable gpg4win-3.1.11.exe exists separately but is also part of Libre Office
- gpg4win's Kleopatra - a tool for managing X.509 and OpenPGP certificates also on Windows
EU DSS - essentially an open-source library
VeraCrypt - TrueCrypt
OpenSSH OpenSSL OpenDnsSect