We use crypto/internal/edwards25519/field to implement X25519 directly,
so that golang.org/x/crypto/curve25519 can be dropped from the src
module dependencies, and eventually replaced with a crypto/ecdh wrapper,
removing the need to keep golang.org/x/crypto/curve25519/internal/field
in sync with crypto/internal/edwards25519/field.
In crypto/internal/nistec, we add BytesX to serialize only the x
coordinate, which we'll need for the horrible ECDSA x-coord-to-scalar
operation, too.
In crypto/tls, we replace the ECDHE implementation with crypto/ecdh,
dropping the X25519 special cases and related scaffolding.
Finally, FINALLY, we deprecate the ~white whale~ big.Int-based APIs of
the crypto/elliptic package. •_•) ( •_•)>⌐■-■ (⌐■_■)
Fixes#52182Fixes#34648Fixes#52221
Change-Id: Iccdda210319cc892e96bb28a0e7b7123551982c7
Reviewed-on: https://go-review.googlesource.com/c/go/+/398914
Reviewed-by: Fernando Lobato Meeser <felobato@google.com>
Reviewed-by: Roland Shoemaker <roland@golang.org>
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gopher Robot <gobot@golang.org>
