This function is currently a no-op, but could be made to do something in
the future to ease the transition of deployments that extract keys from
the handshake and drive the record protocol themselves.
Change-Id: Ib1399e42442dad78173a6462980945559a88a2c7
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/49886
Commit-Queue: Adam Langley <agl@google.com>
Reviewed-by: David Benjamin <davidben@google.com>
Based on an initial implementation by Dan McArdle at
https://boringssl-review.googlesource.com/c/boringssl/+/46784
This CL contains most of a client implementation for
draft-ietf-tls-esni-10. The pieces missing so far, which will be done in
follow-up CLs are:
1. While the ClientHelloInner is padded, the server Certificate message
is not. I'll add that once we resolve the spec discussions on how to
do that. (We were originally going to use TLS record-level padding,
but that doesn't work well with QUIC.)
2. The client should check the public name is a valid DNS name before
copying it into ClientHelloOuter.server_name.
3. The ClientHelloOuter handshake flow is not yet implemented. This CL
can detect when the server selects ClientHelloOuter, but for now the
handshake immediately fails. A follow-up CL will remove that logic
and instead add the APIs and extra checks needed.
Otherwise, this should be complete, including padding and compression.
The main interesting point design-wise is that we run through
ClientHello construction multiple times. We need to construct
ClientHelloInner and ClientHelloOuter. Then each of those has slight
variants: EncodedClientHelloInner is the compressed form, and
ClientHelloOuterAAD just has the ECH extension erased to avoid a
circular dependency.
I've computed ClientHelloInner and EncodedClientHelloInner concurrently
because the compression scheme requires shifting the extensions around
to be contiguous. However, I've computed ClientHelloOuterAAD and
ClientHelloOuter by running through the logic twice. This probably can
be done better, but the next draft revises the construction anyway, so
I'm thinking I'll rework it then. (In the next draft, we use a
placeholder payload of the same length, so we can construct the
ClientHello once and fill in the payload.)
Additionally, now that we have a client available in ssl_test, this adds
a threading test to confirm that SSL_CTX_set1_ech_keys is properly
synchronized. (Confirmed that, if I drop the lock in
SSL_CTX_set1_ech_keys, TSan notices.)
Change-Id: Icaff68b595035bdcc73c468ff638e67c84239ef4
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/48004
Reviewed-by: Adam Langley <agl@google.com>
This is less effective than it seems because both
((const SSL_HANDSHAKE*)hs)->ssl and ((const SSL*)ssl)->s3 are both
non-const pointers. I considered moving hs->ssl to hs->ssl_ and adding
const-overloaded accessors, but I'd need to repeat the same with
ssl->s3, at which point this seemed not worth it yet. Maybe later if we
rewrite everything to more idiomatic C++.
Bug: 275
Change-Id: I9912a3df205916fdf2191a3687013d717528038d
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/47991
Reviewed-by: Adam Langley <agl@google.com>
Adam Langley
David Benjamin