How HMAC is calculated for TLS AES_128_CBC_SHA
Does HMAC cover IV, padding and padding_length fields ?


As stated in 6.2.3.1, for stream and block ciphers, 

The MAC is generated as:

  MAC(MAC_write_key, seq_num +
                        TLSCompressed.type +
                        TLSCompressed.version +
                        TLSCompressed.length +
                        TLSCompressed.fragment);


That is, the MAC is done on the plaintext (that's what TLSCompressed.fragment is, if you don't do compression).  The TLS header is prepended, but no other modification is done.  Hence, it does not include the IV, padding or padding_length.