MINOR: quic: refactor concat DCID with address for Initial packets

For first Initial packets, the socket source dest address is
concatenated to the DCID. This is used to be able to differentiate
possible collision between several clients which used the same ODCID.

Refactor the code to manage DCID and the concatenation with the address.
Before this, the concatenation was done on the quic_cid struct and its
<len> field incremented. In the code it is difficult to differentiate a
normal DCID with a DCID + address concatenated.

A new field <addrlen> has been added in the quic_cid struct. The <len>
field now only contains the size of the QUIC DCID. the <addrlen> is
first initialized to 0. If the address is concatenated, it will be
updated with the size of the concatenated address. This now means we
have to explicitely used either cid.len or cid.len + cid.addrlen to
access the DCID or the DCID + the address. The code should be clearer
thanks to this.

The field <odcid_len> in quic_rx_packet struct is now useless and has
been removed. However, a new parameter must be added to the
qc_new_conn() function to specify the size of the ODCID addrlen.
3 files changed