diff options
Diffstat (limited to 'vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go')
-rw-r--r-- | vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go | 127 |
1 files changed, 0 insertions, 127 deletions
diff --git a/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go b/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go deleted file mode 100644 index 7cd7ad834..000000000 --- a/vendor/golang.org/x/crypto/chacha20poly1305/chacha20poly1305_amd64.go +++ /dev/null @@ -1,127 +0,0 @@ -// Copyright 2016 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 go1.7,amd64,!gccgo,!appengine - -package chacha20poly1305 - -import "encoding/binary" - -//go:noescape -func chacha20Poly1305Open(dst []byte, key []uint32, src, ad []byte) bool - -//go:noescape -func chacha20Poly1305Seal(dst []byte, key []uint32, src, ad []byte) - -// cpuid is implemented in chacha20poly1305_amd64.s. -func cpuid(eaxArg, ecxArg uint32) (eax, ebx, ecx, edx uint32) - -// xgetbv with ecx = 0 is implemented in chacha20poly1305_amd64.s. -func xgetbv() (eax, edx uint32) - -var ( - useASM bool - useAVX2 bool -) - -func init() { - detectCPUFeatures() -} - -// detectCPUFeatures is used to detect if cpu instructions -// used by the functions implemented in assembler in -// chacha20poly1305_amd64.s are supported. -func detectCPUFeatures() { - maxID, _, _, _ := cpuid(0, 0) - if maxID < 1 { - return - } - - _, _, ecx1, _ := cpuid(1, 0) - - haveSSSE3 := isSet(9, ecx1) - useASM = haveSSSE3 - - haveOSXSAVE := isSet(27, ecx1) - - osSupportsAVX := false - // For XGETBV, OSXSAVE bit is required and sufficient. - if haveOSXSAVE { - eax, _ := xgetbv() - // Check if XMM and YMM registers have OS support. - osSupportsAVX = isSet(1, eax) && isSet(2, eax) - } - haveAVX := isSet(28, ecx1) && osSupportsAVX - - if maxID < 7 { - return - } - - _, ebx7, _, _ := cpuid(7, 0) - haveAVX2 := isSet(5, ebx7) && haveAVX - haveBMI2 := isSet(8, ebx7) - - useAVX2 = haveAVX2 && haveBMI2 -} - -// isSet checks if bit at bitpos is set in value. -func isSet(bitpos uint, value uint32) bool { - return value&(1<<bitpos) != 0 -} - -// 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) { - 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[12] = 0 - state[13] = binary.LittleEndian.Uint32(nonce[:4]) - state[14] = binary.LittleEndian.Uint32(nonce[4:8]) - state[15] = binary.LittleEndian.Uint32(nonce[8:12]) -} - -func (c *chacha20poly1305) seal(dst, nonce, plaintext, additionalData []byte) []byte { - if !useASM { - return c.sealGeneric(dst, nonce, plaintext, additionalData) - } - - var state [16]uint32 - setupState(&state, &c.key, nonce) - - ret, out := sliceForAppend(dst, len(plaintext)+16) - chacha20Poly1305Seal(out[:], state[:], plaintext, additionalData) - return ret -} - -func (c *chacha20poly1305) open(dst, nonce, ciphertext, additionalData []byte) ([]byte, error) { - if !useASM { - return c.openGeneric(dst, nonce, ciphertext, additionalData) - } - - var state [16]uint32 - setupState(&state, &c.key, nonce) - - ciphertext = ciphertext[:len(ciphertext)-16] - ret, out := sliceForAppend(dst, len(ciphertext)) - if !chacha20Poly1305Open(out, state[:], ciphertext, additionalData) { - for i := range out { - out[i] = 0 - } - return nil, errOpen - } - - return ret, nil -} |