The CryptoSys API gives you the ability to call fast, efficient cryptographic functions in your programs using Visual Basic, VBA, VB.NET, C/C++, C#, and ASP. It can also be called from VBA applications like Access, Excel and Word. It provides four of the major block cipher algorithms, three stream cipher algorithms, all the major secure message digest hash algorithms, the HMAC, CMAC and Poly1305 message authentication algorithms, a data compression facility, two password-based key derivation functions (PBKDF2 and SCRYPT), and a secure random number generator.
The block cipher algorithms provided are the Advanced Encryption Standard (AES-128, AES-192, AES-256) as specified in FIPS PUB 197; Triple DES (TDEA, 3DES, DES-EDE3); the original Data Encryption Standard (DES) [for legacy applications]; and Bruce Schneier's Blowfish. Key Wrap algorithms for AES and Triple DES are provided. The message digest hash functions are SHA-1, the SHA-2 and SHA-3 families plus RIPEMD-160 and (for legacy applications) MD5 and MD2. The HMAC algorithm is provided for all these hash algorithms and the CMAC algorithm for the block ciphers Triple DES and AES. The stream ciphers are ARCFOUR (RC4), Salsa20 and ChaCha20. The random number generator (RNG) generates cryptographically-secure random numbers to the strict NIST SP800-90 standard, an Approved Random Number Generator for FIPS PUB 140-2.
The CryptoSys API functions allow you to encrypt, decrypt, hash and authenticate data in a variety of formats, as well as generating secure random keys to use in your applications. Your input data can generally be in a byte array, encoded as a hexadecimal string, or in a file. The functions can process the data in a one-off manner, or, for longer inputs, you can call the "update" functions sequentially after initialising. The block cipher algorithms work in Cipher Block Chaining (CBC), Electronic Codebook (ECB), Cipher Feedback (CFB), Output Feedback (OFB), and Counter (CTR) modes. You can generate random keys and nonces in a secure manner. All functions are thread-safe.