This source code is from Thinking in C++, 2nd Edition, Volume 2, by Bruce Eckel & Chuck Allison. You can use Borland, G++ (For version 3 and above only), Microsoft (For C++ with .NET only) to compile and build this source code. Writing perfect software may be a daunting task for developers, but a few defensive techniques which are routinely applied can go a long way toward narrowing the gap between code and ideal. Defensive programming practices are often used where high availability of the application is required, safety if utmost concern, or security is needed for application to work.
This is a slow but working Visual Basic implementation of the 256-bit Serpent algorithm. Serpent was a finalist for Advanced Encryption Standard (AES) and appears to be a very secure powerful algorithm. The Advanced Encryption Standard, or AES, is a symmetric block cipher chosen by the U.S. government for the encryption of classified electronic data and is implemented in software and hardware throughout the world to encrypt sensitive data.
This is a BASE85 Encoding Visual Basic class that expands the text to be encoded by 4:5 i.e. uses 5 ASCII characters to represent 4 bytes with 80% accuracy. Used in Postscript and PDF documents. Useful if binary data needs to be persisted in ASCII text.