I am implementing TLS 1.2 and using ECDHE_RSA_AES_128_GCM_SHA256 cipher suit.

According to RFC 5246 finished messages have {verify_data[verify_data_length]} and verify_data = PRF(master_secret, finished_label, hash(handshake_messages)

Some people said client finished contain Authentication tag and nonce along whit verify data. Can anyone tell me the structure of finished message in this cipher suit and exactly the size of verify data, authentication tag and nonce.

Below is my Client Finished message @Makif can you tell me how may bytes are encrypted and where is authentication tag in this message?

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@Makif, Got it.

-8 byte nonce

-16 byte ciphertext

-16 byte authentication tag

Total is 40 byte but my finished message contain 48 bytes. What is about last 8 byte?



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