Data integrity tools

This popular toolkit is used by many systems. It provides options like encryption and hashing of data, integrity testing, and digital certificates and signatures. Many software applications use the toolkit to provide support for these functions. OpenSSL also has a client utility that can be used on the command line to test, decrypt and encrypt data, and create certificates.

You may need to send some data to untrusted environments. To do this safely, the data needs to be signed. The receiver can check if the signature is correct, while the sender is the only one who can create the appropriate signature.