Retro68/gcc/libgo/go/crypto/aes/cipher_amd64.go
2017-10-07 02:16:47 +02:00

86 lines
1.9 KiB
Go

// Copyright 2012 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build ignore
package aes
import (
"crypto/cipher"
"crypto/internal/cipherhw"
)
// defined in asm_amd64.s
func encryptBlockAsm(nr int, xk *uint32, dst, src *byte)
func decryptBlockAsm(nr int, xk *uint32, dst, src *byte)
func expandKeyAsm(nr int, key *byte, enc *uint32, dec *uint32)
type aesCipherAsm struct {
aesCipher
}
var useAsm = cipherhw.AESGCMSupport()
func newCipher(key []byte) (cipher.Block, error) {
if !useAsm {
return newCipherGeneric(key)
}
n := len(key) + 28
c := aesCipherAsm{aesCipher{make([]uint32, n), make([]uint32, n)}}
rounds := 10
switch len(key) {
case 128 / 8:
rounds = 10
case 192 / 8:
rounds = 12
case 256 / 8:
rounds = 14
}
expandKeyAsm(rounds, &key[0], &c.enc[0], &c.dec[0])
if hasGCMAsm() {
return &aesCipherGCM{c}, nil
}
return &c, nil
}
func (c *aesCipherAsm) BlockSize() int { return BlockSize }
func (c *aesCipherAsm) Encrypt(dst, src []byte) {
if len(src) < BlockSize {
panic("crypto/aes: input not full block")
}
if len(dst) < BlockSize {
panic("crypto/aes: output not full block")
}
encryptBlockAsm(len(c.enc)/4-1, &c.enc[0], &dst[0], &src[0])
}
func (c *aesCipherAsm) Decrypt(dst, src []byte) {
if len(src) < BlockSize {
panic("crypto/aes: input not full block")
}
if len(dst) < BlockSize {
panic("crypto/aes: output not full block")
}
decryptBlockAsm(len(c.dec)/4-1, &c.dec[0], &dst[0], &src[0])
}
// expandKey is used by BenchmarkExpand to ensure that the asm implementation
// of key expansion is used for the benchmark when it is available.
func expandKey(key []byte, enc, dec []uint32) {
if useAsm {
rounds := 10 // rounds needed for AES128
switch len(key) {
case 192 / 8:
rounds = 12
case 256 / 8:
rounds = 14
}
expandKeyAsm(rounds, &key[0], &enc[0], &dec[0])
} else {
expandKeyGo(key, enc, dec)
}
}