Rather than init_msg/init_num, there is a get_message function which
either returns success or try again. This function does not advance the
current message (see the previous preparatory change). It only completes
the current one if necessary.
Being idempotent means it may be freely placed at the top of states
which otherwise have other asychronous operations. It also eases
converting the TLS 1.2 state machine. See
https://docs.google.com/a/google.com/document/d/11n7LHsT3GwE34LAJIe3EFs4165TI4UR_3CqiM9LJVpI/edit?usp=sharing
for details.
The read_message hook (later to be replaced by something which doesn't
depend on BIO) intentionally does not finish the handshake, only "makes
progress". A follow-up change will align both TLS and DTLS on consuming
one handshake record and always consuming the entire record (so init_buf
may contain trailing data). In a few places I've gone ahead and
accounted for that case because it was more natural to do so.
This change also removes a couple pointers of redundant state from every
socket.
Bug: 128
Change-Id: I89d8f3622d3b53147d69ee3ac34bb654ed044a71
Reviewed-on: https://boringssl-review.googlesource.com/18806
Reviewed-by: David Benjamin <davidben@google.com>
Commit-Queue: David Benjamin <davidben@google.com>
CQ-Verified: CQ bot account: commit-bot@chromium.org <commit-bot@chromium.org>
7934f08b26