aes

AES Cipher Core

This directory contains an Anvil implementation of the AES Cipher Core, validated against the baseline SystemVerilog implementation from the OpenTitan IP library.

Prerequisites

• Anvil (available in PATH)
• Verilator (installed and in PATH)
• Python 3
• OpenTitan repository as git submodule at ../../opentitan

Source Files

• aes_cipher_core.anvil - Anvil implementation of AES Cipher Core
• aes_helper_pkg.sv - SystemVerilog wrapper for AES Cipher Core
• aes_cipher_core_tb.anvil - Testbench for encryption and decryption

Test Description

The testbench validates AES encryption and decryption operations using both AES-128 and AES-256 key sizes. The test encrypts plaintext and then decrypts the ciphertext, verifying that the output matches the original input.

Running Anvil Implementation

make clean
make run MODULE_NAME=aes_cipher_core_tb

Running SystemVerilog Baseline

To compare against the OpenTitan baseline implementation:

python3 create_testbench.py aes_cipher_core_tb aes_cipher_core --cleanup
cp ../../scripts/run_testbench.sh ../../opentitan/hw/ip/aes/rtl/
cd ../../opentitan/hw/ip/aes/rtl/
bash run_testbench.sh aes_cipher_core_tb

Expected Output

Both Anvil and OpenTitan baseline implementations produce identical cycle-accurate results, demonstrating functional equivalence. The decrypted output should match the original plaintext for both AES-128 and AES-256 test cases.