- Hash of fragmented certificate was not calculated as a single message and instead we were hashing individual fragments which produced the wrong digest, shared secret, etc...
- Reset handshake number after server Finished packet is sent or received (depending on side)
- Reserve space in buffer for cipher stuff
- Take `DTLS_RECORD_EXTRA` and `DTLS_HANDSHAKE_EXTRA` into size and offset calculations for DTLS path
- Fix renegotiation in DTLS with AES128-SHA
- Fix renegotiation in DTLS with AES-GCM
- Support HelloVerify request during secure renegotiation
- Save renegotiation handshake messages for retransmission in timeout
- Handle cipher parameters from different epochs. DTLS may need to resend and receive messages from previous epochs so handling different sets of encryption and decryption parameters is crucial.