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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.aes-eax encryption scheme

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I already figured it out myself. Lol So, in paper "The EAX Mode of Operation" by M. Bellare, P. Rogaway, and D. Wagner explained that in CTR algorithm and i wasn't aware. The 128-bit auth nonce will be encrypt in ctr mode and concatenate with encrypted nonce+1 until encrypted nonce+m-1, which m is amount of block plaintext. And at last xor it with plaintext.

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