tree 76b862cc2f6eb934770daa5aa288cbd950d4e52e
parent 9b708ad8e1a3fb29b81d7e722d70a4226e2acf7a
author Filippo Valsorda <filippo@golang.org> 1562948942 -0400
committer Filippo Valsorda <filippo@golang.org> 1573508286 +0000

chacha20: expose internal/chacha20 package

const KeySize = 32
const NonceSize = 12
func HChaCha20(key, nonce []byte) ([]byte, error)
type Cipher struct {}
func NewUnauthenticatedCipher(key, nonce []byte) (*Cipher, error)
func (s *Cipher) XORKeyStream(dst, src []byte)

Small performance hit in chacha20poly1305, probably due to the loss
of the Advance API, which we might consider adding later. No new
allocations, thanks to the mid-stack inliner.

name                            old time/op    new time/op    delta
Chacha20Poly1305/Open-64-8        1.60µs ± 0%    1.68µs ± 1%  +4.94%  (p=0.000 n=9+10)
Chacha20Poly1305/Seal-64-8        1.56µs ± 0%    1.64µs ± 1%  +5.21%  (p=0.000 n=8+10)
Chacha20Poly1305/Open-64-X-8      2.10µs ± 1%    2.22µs ± 1%  +5.81%  (p=0.000 n=10+10)
Chacha20Poly1305/Seal-64-X-8      2.07µs ± 1%    2.17µs ± 0%  +4.88%  (p=0.000 n=10+10)
Chacha20Poly1305/Open-1350-8      15.4µs ± 0%    15.7µs ± 1%  +1.65%  (p=0.000 n=10+10)
Chacha20Poly1305/Seal-1350-8      15.6µs ± 2%    15.9µs ± 1%  +1.58%  (p=0.028 n=10+9)
Chacha20Poly1305/Open-1350-X-8    16.0µs ± 1%    16.3µs ± 2%  +2.00%  (p=0.000 n=10+10)
Chacha20Poly1305/Seal-1350-X-8    15.9µs ± 0%    16.3µs ± 1%  +1.91%  (p=0.000 n=10+8)
Chacha20Poly1305/Open-8192-8      85.6µs ± 0%    86.6µs ± 1%  +1.21%  (p=0.000 n=10+10)
Chacha20Poly1305/Seal-8192-8      85.7µs ± 0%    86.3µs ± 0%  +0.68%  (p=0.001 n=9+9)
Chacha20Poly1305/Open-8192-X-8    86.4µs ± 1%    87.1µs ± 1%  +0.76%  (p=0.035 n=10+9)
Chacha20Poly1305/Seal-8192-X-8    86.0µs ± 0%    87.0µs ± 1%  +1.14%  (p=0.000 n=9+9)

Updates golang/go#24485

Change-Id: I2ec2ef487a03f013049915d9063751c75a78408b
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/185980
Reviewed-by: Michael Munday <mike.munday@ibm.com>