Commit Graph
4 Commits
Author SHA1 Message Date
Filippo Valsorda 0848c95719 chacha20poly1305: improve ExampleNewX
The example was failing to direct users on what to do with the nonce,
which should be almost universally prepended to the ciphertext.

Also, leaving key out of the function was pulling the entire file into
the example.

Updates golang/go#38369

Change-Id: I3a13342fff02e1a5d6f9c4ef2a8bddf0b1097707
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/227937
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Katie Hockman <katie@golang.org>
2020-04-14 17:38:20 +00:00
Filippo Valsorda 80fca2ff14 chacha20poly1305: add example for NewX
Change-Id: I619e38a2c8629e851435299fa5204f5fd48a1d87
Reviewed-on: https://go-review.googlesource.com/128055
Reviewed-by: Adam Langley <agl@golang.org>
2018-08-06 19:00:21 +00:00
Filippo Valsorda f792edd33d chacha20poly1305: add XChaCha20-Poly1305
The XChaCha20 construction does not have an authoritative spec, but this
implementation is based on the following documents:

https://cr.yp.to/snuffle/xsalsa-20081128.pdf
https://download.libsodium.org/doc/secret-key_cryptography/aead.html
http://loup-vaillant.fr/tutorials/chacha20-design
https://tools.ietf.org/html/draft-paragon-paseto-rfc-00#section-7

Tested against the following implementations:

https://github.com/jedisct1/libsodium/blob/7cdf3f0e841/test/default/aead_xchacha20poly1305.c
https://git.kernel.org/pub/scm/linux/kernel/git/zx2c4/linux.git/diff/lib/zinc/selftest/chacha20poly1305.h?h=zinc
https://git.zx2c4.com/wireguard-go/tree/xchacha20poly1305/xchacha20.go

name                            time/op          speed
Chacha20Poly1305/Open-64-8         225ns ± 1%     283MB/s ± 1%
Chacha20Poly1305/Open-64-X-8       390ns ± 0%     164MB/s ± 0%
Chacha20Poly1305/Seal-64-8         222ns ± 0%     287MB/s ± 0%
Chacha20Poly1305/Seal-64-X-8       386ns ± 0%     165MB/s ± 1%
Chacha20Poly1305/Open-1350-8      1.12µs ± 1%    1.21GB/s ± 1%
Chacha20Poly1305/Open-1350-X-8    1.28µs ± 0%    1.05GB/s ± 0%
Chacha20Poly1305/Seal-1350-8      1.15µs ± 0%    1.17GB/s ± 0%
Chacha20Poly1305/Seal-1350-X-8    1.32µs ± 1%    1.02GB/s ± 0%
Chacha20Poly1305/Open-8192-8      5.53µs ± 0%    1.48GB/s ± 0%
Chacha20Poly1305/Open-8192-X-8    5.71µs ± 1%    1.44GB/s ± 1%
Chacha20Poly1305/Seal-8192-8      5.54µs ± 1%    1.48GB/s ± 1%
Chacha20Poly1305/Seal-8192-X-8    5.74µs ± 1%    1.43GB/s ± 1%

Updates golang/go#24485

Change-Id: Iea6f3b4c2be67f16f56720a200dcc895c0f9d520
Reviewed-on: https://go-review.googlesource.com/127819
Run-TryBot: Filippo Valsorda <filippo@golang.org>
Reviewed-by: Adam Langley <agl@golang.org>
2018-08-06 17:10:22 +00:00
Adam Langley 594708b89f chacha20poly1305: new package.
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/24717
  https://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>
2016-10-11 21:59:08 +00:00