This change adds a package, chacha20poly1305, which implements the
ChaCha20-Poly1305 AEAD from RFC 7539. This AEAD has several attractive
features:
1. It's naturally constant time. AES-GCM needs either dedicated
hardware or extreme effort to be fast and constant-time, while
this design is easy to make constant-time.
2. It's fast on modern processors: it runs at 1GB/s on my IvyBrige
system.
3. It's seeing significant use in TLS. (A change for crypto/tls is
forthcoming.)
This change merges two CLs:
https://go-review.googlesource.com/#/c/24717https://go-review.googlesource.com/#/c/26691
I took the amd64-optimised AEAD implementation from the former because
it was significantly faster. But the structure of the change is taken
from the latter.
This version will be checked into x/crypto. This package will then be
vendored into the stdlib so that it can be used from crypto/tls.
Change-Id: I5a60587958b7afeec81ca1091e603a7e8517000b
Reviewed-on: https://go-review.googlesource.com/30728
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Adam Langley
594708b89f