| // Copyright 2018 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 go1.11 |
| // +build !gccgo |
| |
| package chacha20 |
| |
| const ( |
| haveAsm = true |
| bufSize = 256 |
| ) |
| |
| //go:noescape |
| func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32) |
| |
| func (c *Cipher) xorKeyStreamAsm(dst, src []byte) { |
| |
| if len(src) >= bufSize { |
| xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter) |
| } |
| |
| if len(src)%bufSize != 0 { |
| i := len(src) - len(src)%bufSize |
| c.buf = [bufSize]byte{} |
| copy(c.buf[:], src[i:]) |
| xorKeyStreamVX(c.buf[:], c.buf[:], &c.key, &c.nonce, &c.counter) |
| c.len = bufSize - copy(dst[i:], c.buf[:len(src)%bufSize]) |
| } |
| } |