Which RFC explains how the mac-then-encrypt needs to be implemented

[Phani 2004 <phani2004@xxxxxxxxx>]

Hi Team,

I am trying to implement mac-then-encrypt for aes_cbc_hmac_sha1 combined cipher. From the code i could understand that the first 16 bytes were being used as explicit IV while decrypting and the hmac is done for 13 bye AAD and 16 byte Fin record in finish message.

Which RFC/section explains this in detail?

Regards

Phani