des-cpp-encrypt is a simple C++ library for generating DES keys and encrypting or decrypting data. Encryption is only implemented for 1 block of data. If you want to encrypt more than 8 bytes, you will need to implement different modes of operation, like des-ecb.
Include DES.h in your project for defining the functions. If you want to compile the library from source, include the cpp file DES.cpp for the implementation. Alternatively, you can compile the source code to a static library and include it that way.
To create round keys, you need a character array of 8 bytes. The DES_CreateKeys function will create 16 round keys based on your input key, which is stored as a [16][8] 2D character array.
char key[8] = {0xAA,0xBB,0x09,0x18,0x27,0x36,0xCC,0xDD};
char roundKeys[16][8];
DES_CreateKeys(key, roundKeys);
After you generated the round keys, you can encrypt some data. You need to provide this data in the form of a character array of 8 bytes. The result is stored in an 8 byte large buffer you also need to provide. The buffer MUST be initialized to 0
char plainText[8] = {'T','e','s','t','D','a','t','a'};
char cipherText[8] = {0,0,0,0,0,0,0,0};
DES_Encrypt(plainText, roundKeys, cipherText);To Decrypt the ciphertext, you need to perform similar steps to encryption. You need to have the round keys, and you need to have an 8 byte ciphertext, and the result is stored in an 8 byte buffer. The buffer MUST be initialized to 0
// 1 Extra character for the null terminator
char original[9] = {0,0,0,0,0,0,0,0,0};
DES_Decrypt(cipherText, roundKeys, original);