chacha20poly1305: update to use new ChaCha20 API

Use the new streaming API introduced in CL 104856. Performance
change is negligible:

name                       old speed      new speed      delta
Chacha20Poly1305Open_64     131MB/s ± 2%   135MB/s ± 2%  +3.01%  (p=0.000 n=18+18)
Chacha20Poly1305Seal_64     137MB/s ± 2%   141MB/s ± 3%  +2.89%  (p=0.000 n=19+20)
Chacha20Poly1305Open_1350   305MB/s ± 3%   309MB/s ± 2%  +1.38%  (p=0.001 n=19+20)
Chacha20Poly1305Seal_1350   309MB/s ± 2%   311MB/s ± 2%  +0.74%  (p=0.032 n=19+18)
Chacha20Poly1305Open_8K     338MB/s ± 3%   340MB/s ± 2%    ~     (p=0.108 n=19+20)
Chacha20Poly1305Seal_8K     335MB/s ± 4%   342MB/s ± 2%  +1.96%  (p=0.000 n=19+19)

Change-Id: I2232c9d8d8431f30fb85b4b371d78a57e633283e
Reviewed-on: https://go-review.googlesource.com/108657
Run-TryBot: Michael Munday <mike.munday@ibm.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
This commit is contained in:
Michael Munday
2018-04-26 23:00:03 +00:00
parent 83c378c48d
commit 754cb46fa0
3 changed files with 36 additions and 24 deletions
+10 -2
View File
@@ -7,6 +7,7 @@ package chacha20poly1305 // import "golang.org/x/crypto/chacha20poly1305"
import (
"crypto/cipher"
"encoding/binary"
"errors"
)
@@ -18,7 +19,7 @@ const (
)
type chacha20poly1305 struct {
key [32]byte
key [8]uint32
}
// New returns a ChaCha20-Poly1305 AEAD that uses the given, 256-bit key.
@@ -27,7 +28,14 @@ func New(key []byte) (cipher.AEAD, error) {
return nil, errors.New("chacha20poly1305: bad key length")
}
ret := new(chacha20poly1305)
copy(ret.key[:], key)
ret.key[0] = binary.LittleEndian.Uint32(key[0:4])
ret.key[1] = binary.LittleEndian.Uint32(key[4:8])
ret.key[2] = binary.LittleEndian.Uint32(key[8:12])
ret.key[3] = binary.LittleEndian.Uint32(key[12:16])
ret.key[4] = binary.LittleEndian.Uint32(key[16:20])
ret.key[5] = binary.LittleEndian.Uint32(key[20:24])
ret.key[6] = binary.LittleEndian.Uint32(key[24:28])
ret.key[7] = binary.LittleEndian.Uint32(key[28:32])
return ret, nil
}
+9 -9
View File
@@ -72,20 +72,20 @@ func isSet(bitpos uint, value uint32) bool {
// setupState writes a ChaCha20 input matrix to state. See
// https://tools.ietf.org/html/rfc7539#section-2.3.
func setupState(state *[16]uint32, key *[32]byte, nonce []byte) {
func setupState(state *[16]uint32, key *[8]uint32, nonce []byte) {
state[0] = 0x61707865
state[1] = 0x3320646e
state[2] = 0x79622d32
state[3] = 0x6b206574
state[4] = binary.LittleEndian.Uint32(key[:4])
state[5] = binary.LittleEndian.Uint32(key[4:8])
state[6] = binary.LittleEndian.Uint32(key[8:12])
state[7] = binary.LittleEndian.Uint32(key[12:16])
state[8] = binary.LittleEndian.Uint32(key[16:20])
state[9] = binary.LittleEndian.Uint32(key[20:24])
state[10] = binary.LittleEndian.Uint32(key[24:28])
state[11] = binary.LittleEndian.Uint32(key[28:32])
state[4] = key[0]
state[5] = key[1]
state[6] = key[2]
state[7] = key[3]
state[8] = key[4]
state[9] = key[5]
state[10] = key[6]
state[11] = key[7]
state[12] = 0
state[13] = binary.LittleEndian.Uint32(nonce[:4])
+17 -13
View File
@@ -16,15 +16,17 @@ func roundTo16(n int) int {
}
func (c *chacha20poly1305) sealGeneric(dst, nonce, plaintext, additionalData []byte) []byte {
var counter [16]byte
copy(counter[4:], nonce)
ret, out := sliceForAppend(dst, len(plaintext)+poly1305.TagSize)
var polyKey [32]byte
chacha20.XORKeyStream(polyKey[:], polyKey[:], &counter, &c.key)
ret, out := sliceForAppend(dst, len(plaintext)+poly1305.TagSize)
counter[0] = 1
chacha20.XORKeyStream(out, plaintext, &counter, &c.key)
s := chacha20.New(c.key, [3]uint32{
binary.LittleEndian.Uint32(nonce[0:4]),
binary.LittleEndian.Uint32(nonce[4:8]),
binary.LittleEndian.Uint32(nonce[8:12]),
})
s.XORKeyStream(polyKey[:], polyKey[:])
s.Advance() // skip the next 32 bytes
s.XORKeyStream(out, plaintext)
polyInput := make([]byte, roundTo16(len(additionalData))+roundTo16(len(plaintext))+8+8)
copy(polyInput, additionalData)
@@ -44,11 +46,14 @@ func (c *chacha20poly1305) openGeneric(dst, nonce, ciphertext, additionalData []
copy(tag[:], ciphertext[len(ciphertext)-16:])
ciphertext = ciphertext[:len(ciphertext)-16]
var counter [16]byte
copy(counter[4:], nonce)
var polyKey [32]byte
chacha20.XORKeyStream(polyKey[:], polyKey[:], &counter, &c.key)
s := chacha20.New(c.key, [3]uint32{
binary.LittleEndian.Uint32(nonce[0:4]),
binary.LittleEndian.Uint32(nonce[4:8]),
binary.LittleEndian.Uint32(nonce[8:12]),
})
s.XORKeyStream(polyKey[:], polyKey[:])
s.Advance() // skip the next 32 bytes
polyInput := make([]byte, roundTo16(len(additionalData))+roundTo16(len(ciphertext))+8+8)
copy(polyInput, additionalData)
@@ -64,7 +69,6 @@ func (c *chacha20poly1305) openGeneric(dst, nonce, ciphertext, additionalData []
return nil, errOpen
}
counter[0] = 1
chacha20.XORKeyStream(out, ciphertext, &counter, &c.key)
s.XORKeyStream(out, ciphertext)
return ret, nil
}