In this paper, we propose a universal hardware API for authenticated ciphers, which can be used in any future implementations of authenticated ciphers submitted to the CAESAR competition. A common interface and communication protocol would help in reducing any potential biases, and would make the comparison in hardware more reliable and fair. By design, our proposed API is equally suitable for hardware implementations of authenticated ciphers developed manually (at the register-transfer level), and those obtained using high-level synthesis tools. Our implementation of the proposed interface and communication protocol includes universal, open-source pre processing and post-processing units, common for all CAESAR candidates. Apart from the full documentation, examples, and the source code of the pre-processing and post-processing units, we are making available in public domain a) a universal testbench to verify the functionality of any CAESAR candidate implemented using the GMU hardware API, b) a Python script used to automatically generate test vectors for this testbench, c) VHDL wrappers used to determine the maximum clock frequency
and the resource utilization of all implementations, and d) RTL VHDL source codes of high-speed implementations of AES and the Keccak Permutation F. We hope that the existence of these resources will substantially reduce the time necessary to develop hardware implementations of all CAESAR candidates for the purpose of evaluation, comparison, and future deployment in real products.