Re: [tinydtls-dev] (no subject)

[Olaf Bergmann <bergmann@xxxxxxx>]

Hi Paolo,

"Veronesi Paolo" <paolo.veronesi@xxxxxxxxxxxxxxxx> writes:

> I need to understand functionality of
> dtls_send_server_key_exchange_ecdh function.
>
> We use dtls_ecdsa_generate_key to create new ECDSA public and private
> keys and after that we call dtls_ecdsa_create_sig passing point_r and
> point_s.
> I can not understand what this function do and what point_r and
> point_s are.

The function dtls_send_server_key_exchange_ecdh() prepares and then
sends the DTLS ServerKeyExchange message containing the ECDSA
signature. RFC 4492 states that "[a]s per ANSI X9.62, an ECDSA signature
consists of a pair of integers, r and s.". These are generated by
dtls_ecdsa_create_sig() as point_r and point_s.

Grüße
Olaf