* RTG-3333 Support X25519MLKEM768 by default, but don't sent it as client
X25519MLKEM768 is the standardised successor of the preliminary
X25519Kyber768Draft00. Latest browsers have switched to X25519MLKEM768.
Cloudflare supports both on the edge.
We've had support for X25519MLKEM768 in this crate for a while, but
didn't enable by default. We're now enabling serverside support by
default. We also let clients advertise support when set
to kx-client-pq-supported.
We don't enable support by default yet for clients set to
kx-client-pq-preferred, as that would cause an extra round-trip due to
HelloRetryRequest if the server doesn't support X25519MLKEM768 yet.
BoringSSL against which we build must support X25519MLKEM768, otherwise
this will fail.
* replace once_cell with LazyLock
We can drop the once_cell dependency since the same functionality is
implemented in std now.
Requires bumping MSRV to 1.80.
* fix manual_c_str_literals clippy warning
---------
Co-authored-by: Bas Westerbaan <bas@cloudflare.com>
Co-authored-by: Alessandro Ghedini <alessandro@cloudflare.com>
According to [the docs](https://doc.rust-lang.org/stable/std/mem/fn.uninitialized.html),
> Calling this when the content is not yet fully initialized causes immediate undefined behavior.
> it [is] undefined behavior to have uninitialized data in a variable even if that variable has an integer type.
Using MaybeUninit instead, as recommended by the official documentation, avoids undefined behavior by not creating a `&mut` reference to uninitialized data.
This ensures that all the Rust functions, types and constants
always match the actual BoringSSL definitions.
It also removes quite a lot of manually maintained code, as well
as the need for systest.
The value for `SslOptions::ALL`, for example, was wrong. On current
BoringSSL versions, this is a no-op, and is set to `0`.
Clearing it does nothing. So, the `clear_ctx_options` test, that
passed by accident, was adjusted to use a different option.
The `libc` crate is not required, as we only use it for types that
are already defined in the standard library. It was removed from
`boring-sys`. The same can be done to other crates later.
0x676e67