C implementation of PRESENT-80. It can encrypt or decrypt a 64-bit block of data using an 80-bit key. A test function is included to demonstrate its operation using a key and plaintext input that are set to all 1's.
The implementation follows the specification as presented in the original work: https://link.springer.com/content/pdf/10.1007/978-3-540-74735-2_31.pdf.