I want to encrypt a message with AES-EAX manually. Then, i confused how ctr mode in AES-EAX processing the nonce which came from omac process. How the counter be concatenate with the nonce in their primitive ctr mode if the nonce already 128-bit length because padding in omac before. My initial nonce length is 96-bit. Should i discard the auth nonce until 96-bit again and concatenate it with 32-bit of counter?
I tried to search that answer in google and didn't find that answer. I also compared my ciphertext calculation with ciphertext from application but it have different result. So, i hope i can find the answer in here. Please help me to know. I really appreciate your answer.