This is a modified version of the AES-128 CBC encryption algorithm. In this custom implementation, encryption and decryption are possible without requiring an Initialization Vector (IV). Instead, the IV is derived from the last and first round key during the encryption and decryption process.

AES-128-CBC implementation in C for secure encryption and decryption. Header-only, easy integration, supports single and multiple block operations. No padding, block size must be 16 bytes. MIT licensed.