CS631 -- Advanced Programming in the UNIX Environment

Write a simple tool to perform encryption/decryption of content

Summary

In this assignment you will write a small, standalone tool following standard Unix conventions that performs encryption or decryption of its input. Even though other tools exist to accomplish this task, it is useful to learn how to perform the basic steps to call the common crypto library functions involved in this task.

Problem assignment

Write a simple program to encrypt or decrypt its input using the AES cipher. Your program is defined in this manual page. As before, your program will:

• follow the general homework guidelines
• be written in C (not C++ or anything else)
• not generate any output other than error messages when appropriate

You may find this link and this link useful. In addition, the EVP_EncryptInit manual page contains code examples which you may use to build your program.