Commit 43ec1b12 authored by Filippo Valsorda's avatar Filippo Valsorda

src/vendor,crypto/tls: update to latest x/crypto and use new X25519 API

Change-Id: Icd5006e37861d892a5f3d4397c3826179c1b12ad
Reviewed-on: https://go-review.googlesource.com/c/go/+/206657
Run-TryBot: Filippo Valsorda <filippo@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: default avatarKatie Hockman <katie@golang.org>
parent 995ade86
......@@ -7,14 +7,14 @@ package tls
import (
"crypto/elliptic"
"crypto/hmac"
"crypto/subtle"
"errors"
"golang.org/x/crypto/cryptobyte"
"golang.org/x/crypto/curve25519"
"golang.org/x/crypto/hkdf"
"hash"
"io"
"math/big"
"golang.org/x/crypto/cryptobyte"
"golang.org/x/crypto/curve25519"
"golang.org/x/crypto/hkdf"
)
// This file contains the functions necessary to compute the TLS 1.3 key
......@@ -111,12 +111,15 @@ type ecdheParameters interface {
func generateECDHEParameters(rand io.Reader, curveID CurveID) (ecdheParameters, error) {
if curveID == X25519 {
p := &x25519Parameters{}
if _, err := io.ReadFull(rand, p.privateKey[:]); err != nil {
privateKey := make([]byte, curve25519.ScalarSize)
if _, err := io.ReadFull(rand, privateKey); err != nil {
return nil, err
}
curve25519.ScalarBaseMult(&p.publicKey, &p.privateKey)
return p, nil
publicKey, err := curve25519.X25519(privateKey, curve25519.Basepoint)
if err != nil {
return nil, err
}
return &x25519Parameters{privateKey: privateKey, publicKey: publicKey}, nil
}
curve, ok := curveForCurveID(curveID)
......@@ -178,8 +181,8 @@ func (p *nistParameters) SharedKey(peerPublicKey []byte) []byte {
}
type x25519Parameters struct {
privateKey [32]byte
publicKey [32]byte
privateKey []byte
publicKey []byte
}
func (p *x25519Parameters) CurveID() CurveID {
......@@ -191,19 +194,9 @@ func (p *x25519Parameters) PublicKey() []byte {
}
func (p *x25519Parameters) SharedKey(peerPublicKey []byte) []byte {
if len(peerPublicKey) != 32 {
return nil
}
var theirPublicKey, sharedKey [32]byte
copy(theirPublicKey[:], peerPublicKey)
curve25519.ScalarMult(&sharedKey, &p.privateKey, &theirPublicKey)
// Check for low-order inputs. See RFC 8422, Section 5.11.
var allZeroes [32]byte
if subtle.ConstantTimeCompare(allZeroes[:], sharedKey[:]) == 1 {
sharedKey, err := curve25519.X25519(p.privateKey, peerPublicKey)
if err != nil {
return nil
}
return sharedKey[:]
return sharedKey
}
......@@ -3,7 +3,7 @@ module std
go 1.14
require (
golang.org/x/crypto v0.0.0-20190611184440-5c40567a22f8
golang.org/x/crypto v0.0.0-20191111213947-16651526fdb4
golang.org/x/net v0.0.0-20191105084925-a882066a44e0
golang.org/x/sys v0.0.0-20190529130038-5219a1e1c5f8 // indirect
golang.org/x/text v0.3.3-0.20191031172631-4b67af870c6f // indirect
......
golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
golang.org/x/crypto v0.0.0-20190611184440-5c40567a22f8 h1:1wopBVtVdWnn03fZelqdXTqk7U7zPQCb+T4rbU9ZEoU=
golang.org/x/crypto v0.0.0-20190611184440-5c40567a22f8/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
golang.org/x/crypto v0.0.0-20191111213947-16651526fdb4 h1:AGVXd+IAyeAb3FuQvYDYQ9+WR2JHm0+C0oYJaU1C4rs=
golang.org/x/crypto v0.0.0-20191111213947-16651526fdb4/go.mod h1:LzIPMQfyMNhhGPhUkYOs5KpL4U8rLKemX1yGLhDgUto=
golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
golang.org/x/net v0.0.0-20191105084925-a882066a44e0 h1:QPlSTtPE2k6PZPasQUbzuK3p9JbS+vMXYVto8g/yrsg=
golang.org/x/net v0.0.0-20191105084925-a882066a44e0/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
......
......@@ -3,29 +3,15 @@
// license that can be found in the LICENSE file.
// +build go1.11
// +build !gccgo
// +build !gccgo,!appengine
package chacha20
const (
haveAsm = true
bufSize = 256
)
const 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 {
func (c *Cipher) xorKeyStreamBlocks(dst, src []byte) {
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])
}
}
// 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.
// Package chacha20 implements the ChaCha20 and XChaCha20 encryption algorithms
// as specified in RFC 8439 and draft-irtf-cfrg-xchacha-01.
package chacha20
import (
"crypto/cipher"
"encoding/binary"
"errors"
"math/bits"
"golang.org/x/crypto/internal/subtle"
)
const (
// KeySize is the size of the key used by this cipher, in bytes.
KeySize = 32
// NonceSize is the size of the nonce used with the standard variant of this
// cipher, in bytes.
//
// Note that this is too short to be safely generated at random if the same
// key is reused more than 2³² times.
NonceSize = 12
// NonceSizeX is the size of the nonce used with the XChaCha20 variant of
// this cipher, in bytes.
NonceSizeX = 24
)
// Cipher is a stateful instance of ChaCha20 or XChaCha20 using a particular key
// and nonce. A *Cipher implements the cipher.Stream interface.
type Cipher struct {
// The ChaCha20 state is 16 words: 4 constant, 8 of key, 1 of counter
// (incremented after each block), and 3 of nonce.
key [8]uint32
counter uint32
nonce [3]uint32
// The last len bytes of buf are leftover key stream bytes from the previous
// XORKeyStream invocation. The size of buf depends on how many blocks are
// computed at a time.
buf [bufSize]byte
len int
// The counter-independent results of the first round are cached after they
// are computed the first time.
precompDone bool
p1, p5, p9, p13 uint32
p2, p6, p10, p14 uint32
p3, p7, p11, p15 uint32
}
var _ cipher.Stream = (*Cipher)(nil)
// NewUnauthenticatedCipher creates a new ChaCha20 stream cipher with the given
// 32 bytes key and a 12 or 24 bytes nonce. If a nonce of 24 bytes is provided,
// the XChaCha20 construction will be used. It returns an error if key or nonce
// have any other length.
//
// Note that ChaCha20, like all stream ciphers, is not authenticated and allows
// attackers to silently tamper with the plaintext. For this reason, it is more
// appropriate as a building block than as a standalone encryption mechanism.
// Instead, consider using package golang.org/x/crypto/chacha20poly1305.
func NewUnauthenticatedCipher(key, nonce []byte) (*Cipher, error) {
// This function is split into a wrapper so that the Cipher allocation will
// be inlined, and depending on how the caller uses the return value, won't
// escape to the heap.
c := &Cipher{}
return newUnauthenticatedCipher(c, key, nonce)
}
func newUnauthenticatedCipher(c *Cipher, key, nonce []byte) (*Cipher, error) {
if len(key) != KeySize {
return nil, errors.New("chacha20: wrong key size")
}
if len(nonce) == NonceSizeX {
// XChaCha20 uses the ChaCha20 core to mix 16 bytes of the nonce into a
// derived key, allowing it to operate on a nonce of 24 bytes. See
// draft-irtf-cfrg-xchacha-01, Section 2.3.
key, _ = HChaCha20(key, nonce[0:16])
cNonce := make([]byte, NonceSize)
copy(cNonce[4:12], nonce[16:24])
nonce = cNonce
} else if len(nonce) != NonceSize {
return nil, errors.New("chacha20: wrong nonce size")
}
c.key = [8]uint32{
binary.LittleEndian.Uint32(key[0:4]),
binary.LittleEndian.Uint32(key[4:8]),
binary.LittleEndian.Uint32(key[8:12]),
binary.LittleEndian.Uint32(key[12:16]),
binary.LittleEndian.Uint32(key[16:20]),
binary.LittleEndian.Uint32(key[20:24]),
binary.LittleEndian.Uint32(key[24:28]),
binary.LittleEndian.Uint32(key[28:32]),
}
c.nonce = [3]uint32{
binary.LittleEndian.Uint32(nonce[0:4]),
binary.LittleEndian.Uint32(nonce[4:8]),
binary.LittleEndian.Uint32(nonce[8:12]),
}
return c, nil
}
// The constant first 4 words of the ChaCha20 state.
const (
j0 uint32 = 0x61707865 // expa
j1 uint32 = 0x3320646e // nd 3
j2 uint32 = 0x79622d32 // 2-by
j3 uint32 = 0x6b206574 // te k
)
const blockSize = 64
// quarterRound is the core of ChaCha20. It shuffles the bits of 4 state words.
// It's executed 4 times for each of the 20 ChaCha20 rounds, operating on all 16
// words each round, in columnar or diagonal groups of 4 at a time.
func quarterRound(a, b, c, d uint32) (uint32, uint32, uint32, uint32) {
a += b
d ^= a
d = bits.RotateLeft32(d, 16)
c += d
b ^= c
b = bits.RotateLeft32(b, 12)
a += b
d ^= a
d = bits.RotateLeft32(d, 8)
c += d
b ^= c
b = bits.RotateLeft32(b, 7)
return a, b, c, d
}
// XORKeyStream XORs each byte in the given slice with a byte from the
// cipher's key stream. Dst and src must overlap entirely or not at all.
//
// If len(dst) < len(src), XORKeyStream will panic. It is acceptable
// to pass a dst bigger than src, and in that case, XORKeyStream will
// only update dst[:len(src)] and will not touch the rest of dst.
//
// Multiple calls to XORKeyStream behave as if the concatenation of
// the src buffers was passed in a single run. That is, Cipher
// maintains state and does not reset at each XORKeyStream call.
func (s *Cipher) XORKeyStream(dst, src []byte) {
if len(src) == 0 {
return
}
if len(dst) < len(src) {
panic("chacha20: output smaller than input")
}
dst = dst[:len(src)]
if subtle.InexactOverlap(dst, src) {
panic("chacha20: invalid buffer overlap")
}
// First, drain any remaining key stream from a previous XORKeyStream.
if s.len != 0 {
keyStream := s.buf[bufSize-s.len:]
if len(src) < len(keyStream) {
keyStream = keyStream[:len(src)]
}
_ = src[len(keyStream)-1] // bounds check elimination hint
for i, b := range keyStream {
dst[i] = src[i] ^ b
}
s.len -= len(keyStream)
src = src[len(keyStream):]
dst = dst[len(keyStream):]
}
const blocksPerBuf = bufSize / blockSize
numBufs := (uint64(len(src)) + bufSize - 1) / bufSize
if uint64(s.counter)+numBufs*blocksPerBuf >= 1<<32 {
panic("chacha20: counter overflow")
}
// xorKeyStreamBlocks implementations expect input lengths that are a
// multiple of bufSize. Platform-specific ones process multiple blocks at a
// time, so have bufSizes that are a multiple of blockSize.
rem := len(src) % bufSize
full := len(src) - rem
if full > 0 {
s.xorKeyStreamBlocks(dst[:full], src[:full])
}
// If we have a partial (multi-)block, pad it for xorKeyStreamBlocks, and
// keep the leftover keystream for the next XORKeyStream invocation.
if rem > 0 {
s.buf = [bufSize]byte{}
copy(s.buf[:], src[full:])
s.xorKeyStreamBlocks(s.buf[:], s.buf[:])
s.len = bufSize - copy(dst[full:], s.buf[:])
}
}
func (s *Cipher) xorKeyStreamBlocksGeneric(dst, src []byte) {
if len(dst) != len(src) || len(dst)%blockSize != 0 {
panic("chacha20: internal error: wrong dst and/or src length")
}
// To generate each block of key stream, the initial cipher state
// (represented below) is passed through 20 rounds of shuffling,
// alternatively applying quarterRounds by columns (like 1, 5, 9, 13)
// or by diagonals (like 1, 6, 11, 12).
//
// 0:cccccccc 1:cccccccc 2:cccccccc 3:cccccccc
// 4:kkkkkkkk 5:kkkkkkkk 6:kkkkkkkk 7:kkkkkkkk
// 8:kkkkkkkk 9:kkkkkkkk 10:kkkkkkkk 11:kkkkkkkk
// 12:bbbbbbbb 13:nnnnnnnn 14:nnnnnnnn 15:nnnnnnnn
//
// c=constant k=key b=blockcount n=nonce
var (
c0, c1, c2, c3 = j0, j1, j2, j3
c4, c5, c6, c7 = s.key[0], s.key[1], s.key[2], s.key[3]
c8, c9, c10, c11 = s.key[4], s.key[5], s.key[6], s.key[7]
_, c13, c14, c15 = s.counter, s.nonce[0], s.nonce[1], s.nonce[2]
)
// Three quarters of the first round don't depend on the counter, so we can
// calculate them here, and reuse them for multiple blocks in the loop, and
// for future XORKeyStream invocations.
if !s.precompDone {
s.p1, s.p5, s.p9, s.p13 = quarterRound(c1, c5, c9, c13)
s.p2, s.p6, s.p10, s.p14 = quarterRound(c2, c6, c10, c14)
s.p3, s.p7, s.p11, s.p15 = quarterRound(c3, c7, c11, c15)
s.precompDone = true
}
for i := 0; i < len(src); i += blockSize {
// The remainder of the first column round.
fcr0, fcr4, fcr8, fcr12 := quarterRound(c0, c4, c8, s.counter)
// The second diagonal round.
x0, x5, x10, x15 := quarterRound(fcr0, s.p5, s.p10, s.p15)
x1, x6, x11, x12 := quarterRound(s.p1, s.p6, s.p11, fcr12)
x2, x7, x8, x13 := quarterRound(s.p2, s.p7, fcr8, s.p13)
x3, x4, x9, x14 := quarterRound(s.p3, fcr4, s.p9, s.p14)
// The remaining 18 rounds.
for i := 0; i < 9; i++ {
// Column round.
x0, x4, x8, x12 = quarterRound(x0, x4, x8, x12)
x1, x5, x9, x13 = quarterRound(x1, x5, x9, x13)
x2, x6, x10, x14 = quarterRound(x2, x6, x10, x14)
x3, x7, x11, x15 = quarterRound(x3, x7, x11, x15)
// Diagonal round.
x0, x5, x10, x15 = quarterRound(x0, x5, x10, x15)
x1, x6, x11, x12 = quarterRound(x1, x6, x11, x12)
x2, x7, x8, x13 = quarterRound(x2, x7, x8, x13)
x3, x4, x9, x14 = quarterRound(x3, x4, x9, x14)
}
// Finally, add back the initial state to generate the key stream.
x0 += c0
x1 += c1
x2 += c2
x3 += c3
x4 += c4
x5 += c5
x6 += c6
x7 += c7
x8 += c8
x9 += c9
x10 += c10
x11 += c11
x12 += s.counter
x13 += c13
x14 += c14
x15 += c15
s.counter += 1
if s.counter == 0 {
panic("chacha20: internal error: counter overflow")
}
in, out := src[i:], dst[i:]
in, out = in[:blockSize], out[:blockSize] // bounds check elimination hint
// XOR the key stream with the source and write out the result.
xor(out[0:], in[0:], x0)
xor(out[4:], in[4:], x1)
xor(out[8:], in[8:], x2)
xor(out[12:], in[12:], x3)
xor(out[16:], in[16:], x4)
xor(out[20:], in[20:], x5)
xor(out[24:], in[24:], x6)
xor(out[28:], in[28:], x7)
xor(out[32:], in[32:], x8)
xor(out[36:], in[36:], x9)
xor(out[40:], in[40:], x10)
xor(out[44:], in[44:], x11)
xor(out[48:], in[48:], x12)
xor(out[52:], in[52:], x13)
xor(out[56:], in[56:], x14)
xor(out[60:], in[60:], x15)
}
}
// HChaCha20 uses the ChaCha20 core to generate a derived key from a 32 bytes
// key and a 16 bytes nonce. It returns an error if key or nonce have any other
// length. It is used as part of the XChaCha20 construction.
func HChaCha20(key, nonce []byte) ([]byte, error) {
// This function is split into a wrapper so that the slice allocation will
// be inlined, and depending on how the caller uses the return value, won't
// escape to the heap.
out := make([]byte, 32)
return hChaCha20(out, key, nonce)
}
func hChaCha20(out, key, nonce []byte) ([]byte, error) {
if len(key) != KeySize {
return nil, errors.New("chacha20: wrong HChaCha20 key size")
}
if len(nonce) != 16 {
return nil, errors.New("chacha20: wrong HChaCha20 nonce size")
}
x0, x1, x2, x3 := j0, j1, j2, j3
x4 := binary.LittleEndian.Uint32(key[0:4])
x5 := binary.LittleEndian.Uint32(key[4:8])
x6 := binary.LittleEndian.Uint32(key[8:12])
x7 := binary.LittleEndian.Uint32(key[12:16])
x8 := binary.LittleEndian.Uint32(key[16:20])
x9 := binary.LittleEndian.Uint32(key[20:24])
x10 := binary.LittleEndian.Uint32(key[24:28])
x11 := binary.LittleEndian.Uint32(key[28:32])
x12 := binary.LittleEndian.Uint32(nonce[0:4])
x13 := binary.LittleEndian.Uint32(nonce[4:8])
x14 := binary.LittleEndian.Uint32(nonce[8:12])
x15 := binary.LittleEndian.Uint32(nonce[12:16])
for i := 0; i < 10; i++ {
// Diagonal round.
x0, x4, x8, x12 = quarterRound(x0, x4, x8, x12)
x1, x5, x9, x13 = quarterRound(x1, x5, x9, x13)
x2, x6, x10, x14 = quarterRound(x2, x6, x10, x14)
x3, x7, x11, x15 = quarterRound(x3, x7, x11, x15)
// Column round.
x0, x5, x10, x15 = quarterRound(x0, x5, x10, x15)
x1, x6, x11, x12 = quarterRound(x1, x6, x11, x12)
x2, x7, x8, x13 = quarterRound(x2, x7, x8, x13)
x3, x4, x9, x14 = quarterRound(x3, x4, x9, x14)
}
_ = out[31] // bounds check elimination hint
binary.LittleEndian.PutUint32(out[0:4], x0)
binary.LittleEndian.PutUint32(out[4:8], x1)
binary.LittleEndian.PutUint32(out[8:12], x2)
binary.LittleEndian.PutUint32(out[12:16], x3)
binary.LittleEndian.PutUint32(out[16:20], x12)
binary.LittleEndian.PutUint32(out[20:24], x13)
binary.LittleEndian.PutUint32(out[24:28], x14)
binary.LittleEndian.PutUint32(out[28:32], x15)
return out, nil
}
......@@ -2,15 +2,12 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build !ppc64le,!arm64,!s390x arm64,!go1.11 gccgo appengine
// +build !arm64,!s390x,!ppc64le arm64,!go1.11 gccgo appengine
package chacha20
const (
bufSize = 64
haveAsm = false
)
const bufSize = blockSize
func (*Cipher) xorKeyStreamAsm(dst, src []byte) {
panic("not implemented")
func (s *Cipher) xorKeyStreamBlocks(dst, src []byte) {
s.xorKeyStreamBlocksGeneric(dst, src)
}
// Copyright 2019 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 !gccgo,!appengine
package chacha20
const bufSize = 256
//go:noescape
func chaCha20_ctr32_vsx(out, inp *byte, len int, key *[8]uint32, counter *uint32)
func (c *Cipher) xorKeyStreamBlocks(dst, src []byte) {
chaCha20_ctr32_vsx(&dst[0], &src[0], len(src), &c.key, &c.counter)
}
// Copyright 2019 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.
// Based on CRYPTOGAMS code with the following comment:
// # ====================================================================
// # Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
// # project. The module is, however, dual licensed under OpenSSL and
// # CRYPTOGAMS licenses depending on where you obtain it. For further
// # details see http://www.openssl.org/~appro/cryptogams/.
// # ====================================================================
// Code for the perl script that generates the ppc64 assembler
// can be found in the cryptogams repository at the link below. It is based on
// the original from openssl.
// https://github.com/dot-asm/cryptogams/commit/a60f5b50ed908e91
// The differences in this and the original implementation are
// due to the calling conventions and initialization of constants.
// +build !gccgo,!appengine
#include "textflag.h"
#define OUT R3
#define INP R4
#define LEN R5
#define KEY R6
#define CNT R7
#define TMP R15
#define CONSTBASE R16
#define BLOCKS R17
DATA consts<>+0x00(SB)/8, $0x3320646e61707865
DATA consts<>+0x08(SB)/8, $0x6b20657479622d32
DATA consts<>+0x10(SB)/8, $0x0000000000000001
DATA consts<>+0x18(SB)/8, $0x0000000000000000
DATA consts<>+0x20(SB)/8, $0x0000000000000004
DATA consts<>+0x28(SB)/8, $0x0000000000000000
DATA consts<>+0x30(SB)/8, $0x0a0b08090e0f0c0d
DATA consts<>+0x38(SB)/8, $0x0203000106070405
DATA consts<>+0x40(SB)/8, $0x090a0b080d0e0f0c
DATA consts<>+0x48(SB)/8, $0x0102030005060704
DATA consts<>+0x50(SB)/8, $0x6170786561707865
DATA consts<>+0x58(SB)/8, $0x6170786561707865
DATA consts<>+0x60(SB)/8, $0x3320646e3320646e
DATA consts<>+0x68(SB)/8, $0x3320646e3320646e
DATA consts<>+0x70(SB)/8, $0x79622d3279622d32
DATA consts<>+0x78(SB)/8, $0x79622d3279622d32
DATA consts<>+0x80(SB)/8, $0x6b2065746b206574
DATA consts<>+0x88(SB)/8, $0x6b2065746b206574
DATA consts<>+0x90(SB)/8, $0x0000000100000000
DATA consts<>+0x98(SB)/8, $0x0000000300000002
GLOBL consts<>(SB), RODATA, $0xa0
//func chaCha20_ctr32_vsx(out, inp *byte, len int, key *[8]uint32, counter *uint32)
TEXT ·chaCha20_ctr32_vsx(SB),NOSPLIT,$64-40
MOVD out+0(FP), OUT
MOVD inp+8(FP), INP
MOVD len+16(FP), LEN
MOVD key+24(FP), KEY
MOVD counter+32(FP), CNT
// Addressing for constants
MOVD $consts<>+0x00(SB), CONSTBASE
MOVD $16, R8
MOVD $32, R9
MOVD $48, R10
MOVD $64, R11
SRD $6, LEN, BLOCKS
// V16
LXVW4X (CONSTBASE)(R0), VS48
ADD $80,CONSTBASE
// Load key into V17,V18
LXVW4X (KEY)(R0), VS49
LXVW4X (KEY)(R8), VS50
// Load CNT, NONCE into V19
LXVW4X (CNT)(R0), VS51
// Clear V27
VXOR V27, V27, V27
// V28
LXVW4X (CONSTBASE)(R11), VS60
// splat slot from V19 -> V26
VSPLTW $0, V19, V26
VSLDOI $4, V19, V27, V19
VSLDOI $12, V27, V19, V19
VADDUWM V26, V28, V26
MOVD $10, R14
MOVD R14, CTR
loop_outer_vsx:
// V0, V1, V2, V3
LXVW4X (R0)(CONSTBASE), VS32
LXVW4X (R8)(CONSTBASE), VS33
LXVW4X (R9)(CONSTBASE), VS34
LXVW4X (R10)(CONSTBASE), VS35
// splat values from V17, V18 into V4-V11
VSPLTW $0, V17, V4
VSPLTW $1, V17, V5
VSPLTW $2, V17, V6
VSPLTW $3, V17, V7
VSPLTW $0, V18, V8
VSPLTW $1, V18, V9
VSPLTW $2, V18, V10
VSPLTW $3, V18, V11
// VOR
VOR V26, V26, V12
// splat values from V19 -> V13, V14, V15
VSPLTW $1, V19, V13
VSPLTW $2, V19, V14
VSPLTW $3, V19, V15
// splat const values
VSPLTISW $-16, V27
VSPLTISW $12, V28
VSPLTISW $8, V29
VSPLTISW $7, V30
loop_vsx:
VADDUWM V0, V4, V0
VADDUWM V1, V5, V1
VADDUWM V2, V6, V2
VADDUWM V3, V7, V3
VXOR V12, V0, V12
VXOR V13, V1, V13
VXOR V14, V2, V14
VXOR V15, V3, V15
VRLW V12, V27, V12
VRLW V13, V27, V13
VRLW V14, V27, V14
VRLW V15, V27, V15
VADDUWM V8, V12, V8
VADDUWM V9, V13, V9
VADDUWM V10, V14, V10
VADDUWM V11, V15, V11
VXOR V4, V8, V4
VXOR V5, V9, V5
VXOR V6, V10, V6
VXOR V7, V11, V7
VRLW V4, V28, V4
VRLW V5, V28, V5
VRLW V6, V28, V6
VRLW V7, V28, V7
VADDUWM V0, V4, V0
VADDUWM V1, V5, V1
VADDUWM V2, V6, V2
VADDUWM V3, V7, V3
VXOR V12, V0, V12
VXOR V13, V1, V13
VXOR V14, V2, V14
VXOR V15, V3, V15
VRLW V12, V29, V12
VRLW V13, V29, V13
VRLW V14, V29, V14
VRLW V15, V29, V15
VADDUWM V8, V12, V8
VADDUWM V9, V13, V9
VADDUWM V10, V14, V10
VADDUWM V11, V15, V11
VXOR V4, V8, V4
VXOR V5, V9, V5
VXOR V6, V10, V6
VXOR V7, V11, V7
VRLW V4, V30, V4
VRLW V5, V30, V5
VRLW V6, V30, V6
VRLW V7, V30, V7
VADDUWM V0, V5, V0
VADDUWM V1, V6, V1
VADDUWM V2, V7, V2
VADDUWM V3, V4, V3
VXOR V15, V0, V15
VXOR V12, V1, V12
VXOR V13, V2, V13
VXOR V14, V3, V14
VRLW V15, V27, V15
VRLW V12, V27, V12
VRLW V13, V27, V13
VRLW V14, V27, V14
VADDUWM V10, V15, V10
VADDUWM V11, V12, V11
VADDUWM V8, V13, V8
VADDUWM V9, V14, V9
VXOR V5, V10, V5
VXOR V6, V11, V6
VXOR V7, V8, V7
VXOR V4, V9, V4
VRLW V5, V28, V5
VRLW V6, V28, V6
VRLW V7, V28, V7
VRLW V4, V28, V4
VADDUWM V0, V5, V0
VADDUWM V1, V6, V1
VADDUWM V2, V7, V2
VADDUWM V3, V4, V3
VXOR V15, V0, V15
VXOR V12, V1, V12
VXOR V13, V2, V13
VXOR V14, V3, V14
VRLW V15, V29, V15
VRLW V12, V29, V12
VRLW V13, V29, V13
VRLW V14, V29, V14
VADDUWM V10, V15, V10
VADDUWM V11, V12, V11
VADDUWM V8, V13, V8
VADDUWM V9, V14, V9
VXOR V5, V10, V5
VXOR V6, V11, V6
VXOR V7, V8, V7
VXOR V4, V9, V4
VRLW V5, V30, V5
VRLW V6, V30, V6
VRLW V7, V30, V7
VRLW V4, V30, V4
BC 16, LT, loop_vsx
VADDUWM V12, V26, V12
WORD $0x13600F8C // VMRGEW V0, V1, V27
WORD $0x13821F8C // VMRGEW V2, V3, V28
WORD $0x10000E8C // VMRGOW V0, V1, V0
WORD $0x10421E8C // VMRGOW V2, V3, V2
WORD $0x13A42F8C // VMRGEW V4, V5, V29
WORD $0x13C63F8C // VMRGEW V6, V7, V30
XXPERMDI VS32, VS34, $0, VS33
XXPERMDI VS32, VS34, $3, VS35
XXPERMDI VS59, VS60, $0, VS32
XXPERMDI VS59, VS60, $3, VS34
WORD $0x10842E8C // VMRGOW V4, V5, V4
WORD $0x10C63E8C // VMRGOW V6, V7, V6
WORD $0x13684F8C // VMRGEW V8, V9, V27
WORD $0x138A5F8C // VMRGEW V10, V11, V28
XXPERMDI VS36, VS38, $0, VS37
XXPERMDI VS36, VS38, $3, VS39
XXPERMDI VS61, VS62, $0, VS36
XXPERMDI VS61, VS62, $3, VS38
WORD $0x11084E8C // VMRGOW V8, V9, V8
WORD $0x114A5E8C // VMRGOW V10, V11, V10
WORD $0x13AC6F8C // VMRGEW V12, V13, V29
WORD $0x13CE7F8C // VMRGEW V14, V15, V30
XXPERMDI VS40, VS42, $0, VS41
XXPERMDI VS40, VS42, $3, VS43
XXPERMDI VS59, VS60, $0, VS40
XXPERMDI VS59, VS60, $3, VS42
WORD $0x118C6E8C // VMRGOW V12, V13, V12
WORD $0x11CE7E8C // VMRGOW V14, V15, V14
VSPLTISW $4, V27
VADDUWM V26, V27, V26
XXPERMDI VS44, VS46, $0, VS45
XXPERMDI VS44, VS46, $3, VS47
XXPERMDI VS61, VS62, $0, VS44
XXPERMDI VS61, VS62, $3, VS46
VADDUWM V0, V16, V0
VADDUWM V4, V17, V4
VADDUWM V8, V18, V8
VADDUWM V12, V19, V12
CMPU LEN, $64
BLT tail_vsx
// Bottom of loop
LXVW4X (INP)(R0), VS59
LXVW4X (INP)(R8), VS60
LXVW4X (INP)(R9), VS61
LXVW4X (INP)(R10), VS62
VXOR V27, V0, V27
VXOR V28, V4, V28
VXOR V29, V8, V29
VXOR V30, V12, V30
STXVW4X VS59, (OUT)(R0)
STXVW4X VS60, (OUT)(R8)
ADD $64, INP
STXVW4X VS61, (OUT)(R9)
ADD $-64, LEN
STXVW4X VS62, (OUT)(R10)
ADD $64, OUT
BEQ done_vsx
VADDUWM V1, V16, V0
VADDUWM V5, V17, V4
VADDUWM V9, V18, V8
VADDUWM V13, V19, V12
CMPU LEN, $64
BLT tail_vsx
LXVW4X (INP)(R0), VS59
LXVW4X (INP)(R8), VS60
LXVW4X (INP)(R9), VS61
LXVW4X (INP)(R10), VS62
VXOR V27, V0, V27
VXOR V28, V4, V28
VXOR V29, V8, V29
VXOR V30, V12, V30
STXVW4X VS59, (OUT)(R0)
STXVW4X VS60, (OUT)(R8)
ADD $64, INP
STXVW4X VS61, (OUT)(R9)
ADD $-64, LEN
STXVW4X VS62, (OUT)(V10)
ADD $64, OUT
BEQ done_vsx
VADDUWM V2, V16, V0
VADDUWM V6, V17, V4
VADDUWM V10, V18, V8
VADDUWM V14, V19, V12
CMPU LEN, $64
BLT tail_vsx
LXVW4X (INP)(R0), VS59
LXVW4X (INP)(R8), VS60
LXVW4X (INP)(R9), VS61
LXVW4X (INP)(R10), VS62
VXOR V27, V0, V27
VXOR V28, V4, V28
VXOR V29, V8, V29
VXOR V30, V12, V30
STXVW4X VS59, (OUT)(R0)
STXVW4X VS60, (OUT)(R8)
ADD $64, INP
STXVW4X VS61, (OUT)(R9)
ADD $-64, LEN
STXVW4X VS62, (OUT)(R10)
ADD $64, OUT
BEQ done_vsx
VADDUWM V3, V16, V0
VADDUWM V7, V17, V4
VADDUWM V11, V18, V8
VADDUWM V15, V19, V12
CMPU LEN, $64
BLT tail_vsx
LXVW4X (INP)(R0), VS59
LXVW4X (INP)(R8), VS60
LXVW4X (INP)(R9), VS61
LXVW4X (INP)(R10), VS62
VXOR V27, V0, V27
VXOR V28, V4, V28
VXOR V29, V8, V29
VXOR V30, V12, V30
STXVW4X VS59, (OUT)(R0)
STXVW4X VS60, (OUT)(R8)
ADD $64, INP
STXVW4X VS61, (OUT)(R9)
ADD $-64, LEN
STXVW4X VS62, (OUT)(R10)
ADD $64, OUT
MOVD $10, R14
MOVD R14, CTR
BNE loop_outer_vsx
done_vsx:
// Increment counter by number of 64 byte blocks
MOVD (CNT), R14
ADD BLOCKS, R14
MOVD R14, (CNT)
RET
tail_vsx:
ADD $32, R1, R11
MOVD LEN, CTR
// Save values on stack to copy from
STXVW4X VS32, (R11)(R0)
STXVW4X VS36, (R11)(R8)
STXVW4X VS40, (R11)(R9)
STXVW4X VS44, (R11)(R10)
ADD $-1, R11, R12
ADD $-1, INP
ADD $-1, OUT
looptail_vsx:
// Copying the result to OUT
// in bytes.
MOVBZU 1(R12), KEY
MOVBZU 1(INP), TMP
XOR KEY, TMP, KEY
MOVBU KEY, 1(OUT)
BC 16, LT, looptail_vsx
// Clear the stack values
STXVW4X VS48, (R11)(R0)
STXVW4X VS48, (R11)(R8)
STXVW4X VS48, (R11)(R9)
STXVW4X VS48, (R11)(R10)
BR done_vsx
......@@ -2,28 +2,25 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build s390x,!gccgo,!appengine
// +build !gccgo,!appengine
package chacha20
import (
"golang.org/x/sys/cpu"
)
import "golang.org/x/sys/cpu"
var haveAsm = cpu.S390X.HasVX
const bufSize = 256
// xorKeyStreamVX is an assembly implementation of XORKeyStream. It must only
// be called when the vector facility is available.
// Implementation in asm_s390x.s.
// be called when the vector facility is available. Implementation in asm_s390x.s.
//go:noescape
func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32, buf *[256]byte, len *int)
func (c *Cipher) xorKeyStreamAsm(dst, src []byte) {
xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter, &c.buf, &c.len)
func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32)
func (c *Cipher) xorKeyStreamBlocks(dst, src []byte) {
if cpu.S390X.HasVX {
xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter)
} else {
c.xorKeyStreamBlocksGeneric(dst, src)
}
}
// EXRL targets, DO NOT CALL!
func mvcSrcToBuf()
func mvcBufToDst()
......@@ -2,7 +2,7 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build s390x,!gccgo,!appengine
// +build !gccgo,!appengine
#include "go_asm.h"
#include "textflag.h"
......@@ -24,15 +24,6 @@ DATA ·constants<>+0x14(SB)/4, $0x3320646e
DATA ·constants<>+0x18(SB)/4, $0x79622d32
DATA ·constants<>+0x1c(SB)/4, $0x6b206574
// EXRL targets:
TEXT ·mvcSrcToBuf(SB), NOFRAME|NOSPLIT, $0
MVC $1, (R1), (R8)
RET
TEXT ·mvcBufToDst(SB), NOFRAME|NOSPLIT, $0
MVC $1, (R8), (R9)
RET
#define BSWAP V5
#define J0 V6
#define KEY0 V7
......@@ -144,7 +135,7 @@ TEXT ·mvcBufToDst(SB), NOFRAME|NOSPLIT, $0
VMRHF v, w, c \ // c = {a[2], b[2], c[2], d[2]}
VMRLF v, w, d // d = {a[3], b[3], c[3], d[3]}
// func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32, buf *[256]byte, len *int)
// func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32)
TEXT ·xorKeyStreamVX(SB), NOSPLIT, $0
MOVD constants<>(SB), R1
MOVD dst+0(FP), R2 // R2=&dst[0]
......@@ -152,25 +143,10 @@ TEXT ·xorKeyStreamVX(SB), NOSPLIT, $0
MOVD key+48(FP), R5 // R5=key
MOVD nonce+56(FP), R6 // R6=nonce
MOVD counter+64(FP), R7 // R7=counter
MOVD buf+72(FP), R8 // R8=buf
MOVD len+80(FP), R9 // R9=len
// load BSWAP and J0
VLM (R1), BSWAP, J0
// set up tail buffer
ADD $-1, R4, R12
MOVBZ R12, R12
CMPUBEQ R12, $255, aligned
MOVD R4, R1
AND $~255, R1
MOVD $(R3)(R1*1), R1
EXRL mvcSrcToBuf(SB), R12
MOVD $255, R0
SUB R12, R0
MOVD R0, (R9) // update len
aligned:
// setup
MOVD $95, R0
VLM (R5), KEY0, KEY1
......@@ -217,9 +193,7 @@ loop:
// decrement length
ADD $-256, R4
BLT tail
continue:
// rearrange vectors
SHUFFLE(X0, X1, X2, X3, M0, M1, M2, M3)
ADDV(J0, X0, X1, X2, X3)
......@@ -245,16 +219,6 @@ continue:
MOVD $256(R3), R3
CMPBNE R4, $0, chacha
CMPUBEQ R12, $255, return
EXRL mvcBufToDst(SB), R12 // len was updated during setup
return:
VSTEF $0, CTR, (R7)
RET
tail:
MOVD R2, R9
MOVD R8, R2
MOVD R8, R3
MOVD $0, R4
JMP continue
......@@ -4,9 +4,7 @@
package chacha20
import (
"runtime"
)
import "runtime"
// Platforms that have fast unaligned 32-bit little endian accesses.
const unaligned = runtime.GOARCH == "386" ||
......
......@@ -2,13 +2,13 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package chacha20poly1305 implements the ChaCha20-Poly1305 AEAD as specified in RFC 7539,
// and its extended nonce variant XChaCha20-Poly1305.
// Package chacha20poly1305 implements the ChaCha20-Poly1305 AEAD and its
// extended nonce variant XChaCha20-Poly1305, as specified in RFC 8439 and
// draft-irtf-cfrg-xchacha-01.
package chacha20poly1305 // import "golang.org/x/crypto/chacha20poly1305"
import (
"crypto/cipher"
"encoding/binary"
"errors"
)
......@@ -29,7 +29,7 @@ const (
)
type chacha20poly1305 struct {
key [8]uint32
key [KeySize]byte
}
// New returns a ChaCha20-Poly1305 AEAD that uses the given 256-bit key.
......@@ -38,14 +38,7 @@ func New(key []byte) (cipher.AEAD, error) {
return nil, errors.New("chacha20poly1305: bad key length")
}
ret := new(chacha20poly1305)
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])
copy(ret.key[:], key)
return ret, nil
}
......
......@@ -25,23 +25,23 @@ var (
// setupState writes a ChaCha20 input matrix to state. See
// https://tools.ietf.org/html/rfc7539#section-2.3.
func setupState(state *[16]uint32, key *[8]uint32, nonce []byte) {
func setupState(state *[16]uint32, key *[32]byte, nonce []byte) {
state[0] = 0x61707865
state[1] = 0x3320646e
state[2] = 0x79622d32
state[3] = 0x6b206574
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[4] = binary.LittleEndian.Uint32(key[0:4])
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[13] = binary.LittleEndian.Uint32(nonce[0:4])
state[14] = binary.LittleEndian.Uint32(nonce[4:8])
state[15] = binary.LittleEndian.Uint32(nonce[8:12])
}
......
......@@ -7,7 +7,7 @@ package chacha20poly1305
import (
"encoding/binary"
"golang.org/x/crypto/internal/chacha20"
"golang.org/x/crypto/chacha20"
"golang.org/x/crypto/internal/subtle"
"golang.org/x/crypto/poly1305"
)
......@@ -22,14 +22,10 @@ func (c *chacha20poly1305) sealGeneric(dst, nonce, plaintext, additionalData []b
panic("chacha20poly1305: invalid buffer overlap")
}
var polyKey [32]byte
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]),
})
var polyKey, discardBuf [32]byte
s, _ := chacha20.NewUnauthenticatedCipher(c.key[:], nonce)
s.XORKeyStream(polyKey[:], polyKey[:])
s.Advance() // skip the next 32 bytes
s.XORKeyStream(discardBuf[:], discardBuf[:]) // skip the next 32 bytes
s.XORKeyStream(out, plaintext)
polyInput := make([]byte, roundTo16(len(additionalData))+roundTo16(len(plaintext))+8+8)
......@@ -50,14 +46,10 @@ func (c *chacha20poly1305) openGeneric(dst, nonce, ciphertext, additionalData []
copy(tag[:], ciphertext[len(ciphertext)-16:])
ciphertext = ciphertext[:len(ciphertext)-16]
var polyKey [32]byte
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]),
})
var polyKey, discardBuf [32]byte
s, _ := chacha20.NewUnauthenticatedCipher(c.key[:], nonce)
s.XORKeyStream(polyKey[:], polyKey[:])
s.Advance() // skip the next 32 bytes
s.XORKeyStream(discardBuf[:], discardBuf[:]) // skip the next 32 bytes
polyInput := make([]byte, roundTo16(len(additionalData))+roundTo16(len(ciphertext))+8+8)
copy(polyInput, additionalData)
......
......@@ -6,14 +6,13 @@ package chacha20poly1305
import (
"crypto/cipher"
"encoding/binary"
"errors"
"golang.org/x/crypto/internal/chacha20"
"golang.org/x/crypto/chacha20"
)
type xchacha20poly1305 struct {
key [8]uint32
key [KeySize]byte
}
// NewX returns a XChaCha20-Poly1305 AEAD that uses the given 256-bit key.
......@@ -27,14 +26,7 @@ func NewX(key []byte) (cipher.AEAD, error) {
return nil, errors.New("chacha20poly1305: bad key length")
}
ret := new(xchacha20poly1305)
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])
copy(ret.key[:], key)
return ret, nil
}
......@@ -60,15 +52,10 @@ func (x *xchacha20poly1305) Seal(dst, nonce, plaintext, additionalData []byte) [
panic("chacha20poly1305: plaintext too large")
}
hNonce := [4]uint32{
binary.LittleEndian.Uint32(nonce[0:4]),
binary.LittleEndian.Uint32(nonce[4:8]),
binary.LittleEndian.Uint32(nonce[8:12]),
binary.LittleEndian.Uint32(nonce[12:16]),
}
c := &chacha20poly1305{
key: chacha20.HChaCha20(&x.key, &hNonce),
}
c := new(chacha20poly1305)
hKey, _ := chacha20.HChaCha20(x.key[:], nonce[0:16])
copy(c.key[:], hKey)
// The first 4 bytes of the final nonce are unused counter space.
cNonce := make([]byte, NonceSize)
copy(cNonce[4:12], nonce[16:24])
......@@ -87,15 +74,10 @@ func (x *xchacha20poly1305) Open(dst, nonce, ciphertext, additionalData []byte)
panic("chacha20poly1305: ciphertext too large")
}
hNonce := [4]uint32{
binary.LittleEndian.Uint32(nonce[0:4]),
binary.LittleEndian.Uint32(nonce[4:8]),
binary.LittleEndian.Uint32(nonce[8:12]),
binary.LittleEndian.Uint32(nonce[12:16]),
}
c := &chacha20poly1305{
key: chacha20.HChaCha20(&x.key, &hNonce),
}
c := new(chacha20poly1305)
hKey, _ := chacha20.HChaCha20(x.key[:], nonce[0:16])
copy(c.key[:], hKey)
// The first 4 bytes of the final nonce are unused counter space.
cNonce := make([]byte, NonceSize)
copy(cNonce[4:12], nonce[16:24])
......
// 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.
// This code was translated into a form compatible with 6a from the public
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// +build amd64,!gccgo,!appengine
// These constants cannot be encoded in non-MOVQ immediates.
// We access them directly from memory instead.
DATA ·_121666_213(SB)/8, $996687872
GLOBL ·_121666_213(SB), 8, $8
DATA ·_2P0(SB)/8, $0xFFFFFFFFFFFDA
GLOBL ·_2P0(SB), 8, $8
DATA ·_2P1234(SB)/8, $0xFFFFFFFFFFFFE
GLOBL ·_2P1234(SB), 8, $8
// 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 amd64,!gccgo,!appengine
// func cswap(inout *[4][5]uint64, v uint64)
TEXT ·cswap(SB),7,$0
MOVQ inout+0(FP),DI
MOVQ v+8(FP),SI
SUBQ $1, SI
NOTQ SI
MOVQ SI, X15
PSHUFD $0x44, X15, X15
MOVOU 0(DI), X0
MOVOU 16(DI), X2
MOVOU 32(DI), X4
MOVOU 48(DI), X6
MOVOU 64(DI), X8
MOVOU 80(DI), X1
MOVOU 96(DI), X3
MOVOU 112(DI), X5
MOVOU 128(DI), X7
MOVOU 144(DI), X9
MOVO X1, X10
MOVO X3, X11
MOVO X5, X12
MOVO X7, X13
MOVO X9, X14
PXOR X0, X10
PXOR X2, X11
PXOR X4, X12
PXOR X6, X13
PXOR X8, X14
PAND X15, X10
PAND X15, X11
PAND X15, X12
PAND X15, X13
PAND X15, X14
PXOR X10, X0
PXOR X10, X1
PXOR X11, X2
PXOR X11, X3
PXOR X12, X4
PXOR X12, X5
PXOR X13, X6
PXOR X13, X7
PXOR X14, X8
PXOR X14, X9
MOVOU X0, 0(DI)
MOVOU X2, 16(DI)
MOVOU X4, 32(DI)
MOVOU X6, 48(DI)
MOVOU X8, 64(DI)
MOVOU X1, 80(DI)
MOVOU X3, 96(DI)
MOVOU X5, 112(DI)
MOVOU X7, 128(DI)
MOVOU X9, 144(DI)
RET
// Copyright 2013 The Go Authors. All rights reserved.
// Copyright 2019 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.
// We have an implementation in amd64 assembly so this code is only run on
// non-amd64 platforms. The amd64 assembly does not support gccgo.
// +build !amd64 gccgo appengine
package curve25519
// Package curve25519 provides an implementation of the X25519 function, which
// performs scalar multiplication on the elliptic curve known as Curve25519.
// See RFC 7748.
package curve25519 // import "golang.org/x/crypto/curve25519"
import (
"encoding/binary"
"crypto/subtle"
"fmt"
)
// This code is a port of the public domain, "ref10" implementation of
// curve25519 from SUPERCOP 20130419 by D. J. Bernstein.
// fieldElement represents an element of the field GF(2^255 - 19). An element
// t, entries t[0]...t[9], represents the integer t[0]+2^26 t[1]+2^51 t[2]+2^77
// t[3]+2^102 t[4]+...+2^230 t[9]. Bounds on each t[i] vary depending on
// context.
type fieldElement [10]int32
func feZero(fe *fieldElement) {
for i := range fe {
fe[i] = 0
}
}
func feOne(fe *fieldElement) {
feZero(fe)
fe[0] = 1
}
func feAdd(dst, a, b *fieldElement) {
for i := range dst {
dst[i] = a[i] + b[i]
}
}
func feSub(dst, a, b *fieldElement) {
for i := range dst {
dst[i] = a[i] - b[i]
}
}
func feCopy(dst, src *fieldElement) {
for i := range dst {
dst[i] = src[i]
}
}
// feCSwap replaces (f,g) with (g,f) if b == 1; replaces (f,g) with (f,g) if b == 0.
//
// Preconditions: b in {0,1}.
func feCSwap(f, g *fieldElement, b int32) {
b = -b
for i := range f {
t := b & (f[i] ^ g[i])
f[i] ^= t
g[i] ^= t
}
}
// load3 reads a 24-bit, little-endian value from in.
func load3(in []byte) int64 {
var r int64
r = int64(in[0])
r |= int64(in[1]) << 8
r |= int64(in[2]) << 16
return r
}
// load4 reads a 32-bit, little-endian value from in.
func load4(in []byte) int64 {
return int64(binary.LittleEndian.Uint32(in))
}
func feFromBytes(dst *fieldElement, src *[32]byte) {
h0 := load4(src[:])
h1 := load3(src[4:]) << 6
h2 := load3(src[7:]) << 5
h3 := load3(src[10:]) << 3
h4 := load3(src[13:]) << 2
h5 := load4(src[16:])
h6 := load3(src[20:]) << 7
h7 := load3(src[23:]) << 5
h8 := load3(src[26:]) << 4
h9 := (load3(src[29:]) & 0x7fffff) << 2
var carry [10]int64
carry[9] = (h9 + 1<<24) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
carry[1] = (h1 + 1<<24) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[3] = (h3 + 1<<24) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[5] = (h5 + 1<<24) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
carry[7] = (h7 + 1<<24) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
carry[0] = (h0 + 1<<25) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[2] = (h2 + 1<<25) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[4] = (h4 + 1<<25) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[6] = (h6 + 1<<25) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
carry[8] = (h8 + 1<<25) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
dst[0] = int32(h0)
dst[1] = int32(h1)
dst[2] = int32(h2)
dst[3] = int32(h3)
dst[4] = int32(h4)
dst[5] = int32(h5)
dst[6] = int32(h6)
dst[7] = int32(h7)
dst[8] = int32(h8)
dst[9] = int32(h9)
}
// feToBytes marshals h to s.
// Preconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
//
// Write p=2^255-19; q=floor(h/p).
// Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
//
// Proof:
// Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
// Also have |h-2^230 h9|<2^230 so |19 2^(-255)(h-2^230 h9)|<1/4.
// ScalarMult sets dst to the product scalar * point.
//
// Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
// Then 0<y<1.
//
// Write r=h-pq.
// Have 0<=r<=p-1=2^255-20.
// Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
//
// Write x=r+19(2^-255)r+y.
// Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
//
// Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
// so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
func feToBytes(s *[32]byte, h *fieldElement) {
var carry [10]int32
q := (19*h[9] + (1 << 24)) >> 25
q = (h[0] + q) >> 26
q = (h[1] + q) >> 25
q = (h[2] + q) >> 26
q = (h[3] + q) >> 25
q = (h[4] + q) >> 26
q = (h[5] + q) >> 25
q = (h[6] + q) >> 26
q = (h[7] + q) >> 25
q = (h[8] + q) >> 26
q = (h[9] + q) >> 25
// Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20.
h[0] += 19 * q
// Goal: Output h-2^255 q, which is between 0 and 2^255-20.
carry[0] = h[0] >> 26
h[1] += carry[0]
h[0] -= carry[0] << 26
carry[1] = h[1] >> 25
h[2] += carry[1]
h[1] -= carry[1] << 25
carry[2] = h[2] >> 26
h[3] += carry[2]
h[2] -= carry[2] << 26
carry[3] = h[3] >> 25
h[4] += carry[3]
h[3] -= carry[3] << 25
carry[4] = h[4] >> 26
h[5] += carry[4]
h[4] -= carry[4] << 26
carry[5] = h[5] >> 25
h[6] += carry[5]
h[5] -= carry[5] << 25
carry[6] = h[6] >> 26
h[7] += carry[6]
h[6] -= carry[6] << 26
carry[7] = h[7] >> 25
h[8] += carry[7]
h[7] -= carry[7] << 25
carry[8] = h[8] >> 26
h[9] += carry[8]
h[8] -= carry[8] << 26
carry[9] = h[9] >> 25
h[9] -= carry[9] << 25
// h10 = carry9
// Goal: Output h[0]+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
// Have h[0]+...+2^230 h[9] between 0 and 2^255-1;
// evidently 2^255 h10-2^255 q = 0.
// Goal: Output h[0]+...+2^230 h[9].
s[0] = byte(h[0] >> 0)
s[1] = byte(h[0] >> 8)
s[2] = byte(h[0] >> 16)
s[3] = byte((h[0] >> 24) | (h[1] << 2))
s[4] = byte(h[1] >> 6)
s[5] = byte(h[1] >> 14)
s[6] = byte((h[1] >> 22) | (h[2] << 3))
s[7] = byte(h[2] >> 5)
s[8] = byte(h[2] >> 13)
s[9] = byte((h[2] >> 21) | (h[3] << 5))
s[10] = byte(h[3] >> 3)
s[11] = byte(h[3] >> 11)
s[12] = byte((h[3] >> 19) | (h[4] << 6))
s[13] = byte(h[4] >> 2)
s[14] = byte(h[4] >> 10)
s[15] = byte(h[4] >> 18)
s[16] = byte(h[5] >> 0)
s[17] = byte(h[5] >> 8)
s[18] = byte(h[5] >> 16)
s[19] = byte((h[5] >> 24) | (h[6] << 1))
s[20] = byte(h[6] >> 7)
s[21] = byte(h[6] >> 15)
s[22] = byte((h[6] >> 23) | (h[7] << 3))
s[23] = byte(h[7] >> 5)
s[24] = byte(h[7] >> 13)
s[25] = byte((h[7] >> 21) | (h[8] << 4))
s[26] = byte(h[8] >> 4)
s[27] = byte(h[8] >> 12)
s[28] = byte((h[8] >> 20) | (h[9] << 6))
s[29] = byte(h[9] >> 2)
s[30] = byte(h[9] >> 10)
s[31] = byte(h[9] >> 18)
// Deprecated: when provided a low-order point, ScalarMult will set dst to all
// zeroes, irrespective of the scalar. Instead, use the X25519 function, which
// will return an error.
func ScalarMult(dst, scalar, point *[32]byte) {
scalarMult(dst, scalar, point)
}
// feMul calculates h = f * g
// Can overlap h with f or g.
//
// Preconditions:
// |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
// |g| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
//
// Postconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
// ScalarBaseMult sets dst to the product scalar * base where base is the
// standard generator.
//
// Notes on implementation strategy:
//
// Using schoolbook multiplication.
// Karatsuba would save a little in some cost models.
//
// Most multiplications by 2 and 19 are 32-bit precomputations;
// cheaper than 64-bit postcomputations.
//
// There is one remaining multiplication by 19 in the carry chain;
// one *19 precomputation can be merged into this,
// but the resulting data flow is considerably less clean.
//
// There are 12 carries below.
// 10 of them are 2-way parallelizable and vectorizable.
// Can get away with 11 carries, but then data flow is much deeper.
//
// With tighter constraints on inputs can squeeze carries into int32.
func feMul(h, f, g *fieldElement) {
f0 := f[0]
f1 := f[1]
f2 := f[2]
f3 := f[3]
f4 := f[4]
f5 := f[5]
f6 := f[6]
f7 := f[7]
f8 := f[8]
f9 := f[9]
g0 := g[0]
g1 := g[1]
g2 := g[2]
g3 := g[3]
g4 := g[4]
g5 := g[5]
g6 := g[6]
g7 := g[7]
g8 := g[8]
g9 := g[9]
g1_19 := 19 * g1 // 1.4*2^29
g2_19 := 19 * g2 // 1.4*2^30; still ok
g3_19 := 19 * g3
g4_19 := 19 * g4
g5_19 := 19 * g5
g6_19 := 19 * g6
g7_19 := 19 * g7
g8_19 := 19 * g8
g9_19 := 19 * g9
f1_2 := 2 * f1
f3_2 := 2 * f3
f5_2 := 2 * f5
f7_2 := 2 * f7
f9_2 := 2 * f9
f0g0 := int64(f0) * int64(g0)
f0g1 := int64(f0) * int64(g1)
f0g2 := int64(f0) * int64(g2)
f0g3 := int64(f0) * int64(g3)
f0g4 := int64(f0) * int64(g4)
f0g5 := int64(f0) * int64(g5)
f0g6 := int64(f0) * int64(g6)
f0g7 := int64(f0) * int64(g7)
f0g8 := int64(f0) * int64(g8)
f0g9 := int64(f0) * int64(g9)
f1g0 := int64(f1) * int64(g0)
f1g1_2 := int64(f1_2) * int64(g1)
f1g2 := int64(f1) * int64(g2)
f1g3_2 := int64(f1_2) * int64(g3)
f1g4 := int64(f1) * int64(g4)
f1g5_2 := int64(f1_2) * int64(g5)
f1g6 := int64(f1) * int64(g6)
f1g7_2 := int64(f1_2) * int64(g7)
f1g8 := int64(f1) * int64(g8)
f1g9_38 := int64(f1_2) * int64(g9_19)
f2g0 := int64(f2) * int64(g0)
f2g1 := int64(f2) * int64(g1)
f2g2 := int64(f2) * int64(g2)
f2g3 := int64(f2) * int64(g3)
f2g4 := int64(f2) * int64(g4)
f2g5 := int64(f2) * int64(g5)
f2g6 := int64(f2) * int64(g6)
f2g7 := int64(f2) * int64(g7)
f2g8_19 := int64(f2) * int64(g8_19)
f2g9_19 := int64(f2) * int64(g9_19)
f3g0 := int64(f3) * int64(g0)
f3g1_2 := int64(f3_2) * int64(g1)
f3g2 := int64(f3) * int64(g2)
f3g3_2 := int64(f3_2) * int64(g3)
f3g4 := int64(f3) * int64(g4)
f3g5_2 := int64(f3_2) * int64(g5)
f3g6 := int64(f3) * int64(g6)
f3g7_38 := int64(f3_2) * int64(g7_19)
f3g8_19 := int64(f3) * int64(g8_19)
f3g9_38 := int64(f3_2) * int64(g9_19)
f4g0 := int64(f4) * int64(g0)
f4g1 := int64(f4) * int64(g1)
f4g2 := int64(f4) * int64(g2)
f4g3 := int64(f4) * int64(g3)
f4g4 := int64(f4) * int64(g4)
f4g5 := int64(f4) * int64(g5)
f4g6_19 := int64(f4) * int64(g6_19)
f4g7_19 := int64(f4) * int64(g7_19)
f4g8_19 := int64(f4) * int64(g8_19)
f4g9_19 := int64(f4) * int64(g9_19)
f5g0 := int64(f5) * int64(g0)
f5g1_2 := int64(f5_2) * int64(g1)
f5g2 := int64(f5) * int64(g2)
f5g3_2 := int64(f5_2) * int64(g3)
f5g4 := int64(f5) * int64(g4)
f5g5_38 := int64(f5_2) * int64(g5_19)
f5g6_19 := int64(f5) * int64(g6_19)
f5g7_38 := int64(f5_2) * int64(g7_19)
f5g8_19 := int64(f5) * int64(g8_19)
f5g9_38 := int64(f5_2) * int64(g9_19)
f6g0 := int64(f6) * int64(g0)
f6g1 := int64(f6) * int64(g1)
f6g2 := int64(f6) * int64(g2)
f6g3 := int64(f6) * int64(g3)
f6g4_19 := int64(f6) * int64(g4_19)
f6g5_19 := int64(f6) * int64(g5_19)
f6g6_19 := int64(f6) * int64(g6_19)
f6g7_19 := int64(f6) * int64(g7_19)
f6g8_19 := int64(f6) * int64(g8_19)
f6g9_19 := int64(f6) * int64(g9_19)
f7g0 := int64(f7) * int64(g0)
f7g1_2 := int64(f7_2) * int64(g1)
f7g2 := int64(f7) * int64(g2)
f7g3_38 := int64(f7_2) * int64(g3_19)
f7g4_19 := int64(f7) * int64(g4_19)
f7g5_38 := int64(f7_2) * int64(g5_19)
f7g6_19 := int64(f7) * int64(g6_19)
f7g7_38 := int64(f7_2) * int64(g7_19)
f7g8_19 := int64(f7) * int64(g8_19)
f7g9_38 := int64(f7_2) * int64(g9_19)
f8g0 := int64(f8) * int64(g0)
f8g1 := int64(f8) * int64(g1)
f8g2_19 := int64(f8) * int64(g2_19)
f8g3_19 := int64(f8) * int64(g3_19)
f8g4_19 := int64(f8) * int64(g4_19)
f8g5_19 := int64(f8) * int64(g5_19)
f8g6_19 := int64(f8) * int64(g6_19)
f8g7_19 := int64(f8) * int64(g7_19)
f8g8_19 := int64(f8) * int64(g8_19)
f8g9_19 := int64(f8) * int64(g9_19)
f9g0 := int64(f9) * int64(g0)
f9g1_38 := int64(f9_2) * int64(g1_19)
f9g2_19 := int64(f9) * int64(g2_19)
f9g3_38 := int64(f9_2) * int64(g3_19)
f9g4_19 := int64(f9) * int64(g4_19)
f9g5_38 := int64(f9_2) * int64(g5_19)
f9g6_19 := int64(f9) * int64(g6_19)
f9g7_38 := int64(f9_2) * int64(g7_19)
f9g8_19 := int64(f9) * int64(g8_19)
f9g9_38 := int64(f9_2) * int64(g9_19)
h0 := f0g0 + f1g9_38 + f2g8_19 + f3g7_38 + f4g6_19 + f5g5_38 + f6g4_19 + f7g3_38 + f8g2_19 + f9g1_38
h1 := f0g1 + f1g0 + f2g9_19 + f3g8_19 + f4g7_19 + f5g6_19 + f6g5_19 + f7g4_19 + f8g3_19 + f9g2_19
h2 := f0g2 + f1g1_2 + f2g0 + f3g9_38 + f4g8_19 + f5g7_38 + f6g6_19 + f7g5_38 + f8g4_19 + f9g3_38
h3 := f0g3 + f1g2 + f2g1 + f3g0 + f4g9_19 + f5g8_19 + f6g7_19 + f7g6_19 + f8g5_19 + f9g4_19
h4 := f0g4 + f1g3_2 + f2g2 + f3g1_2 + f4g0 + f5g9_38 + f6g8_19 + f7g7_38 + f8g6_19 + f9g5_38
h5 := f0g5 + f1g4 + f2g3 + f3g2 + f4g1 + f5g0 + f6g9_19 + f7g8_19 + f8g7_19 + f9g6_19
h6 := f0g6 + f1g5_2 + f2g4 + f3g3_2 + f4g2 + f5g1_2 + f6g0 + f7g9_38 + f8g8_19 + f9g7_38
h7 := f0g7 + f1g6 + f2g5 + f3g4 + f4g3 + f5g2 + f6g1 + f7g0 + f8g9_19 + f9g8_19
h8 := f0g8 + f1g7_2 + f2g6 + f3g5_2 + f4g4 + f5g3_2 + f6g2 + f7g1_2 + f8g0 + f9g9_38
h9 := f0g9 + f1g8 + f2g7 + f3g6 + f4g5 + f5g4 + f6g3 + f7g2 + f8g1 + f9g0
var carry [10]int64
// |h0| <= (1.1*1.1*2^52*(1+19+19+19+19)+1.1*1.1*2^50*(38+38+38+38+38))
// i.e. |h0| <= 1.2*2^59; narrower ranges for h2, h4, h6, h8
// |h1| <= (1.1*1.1*2^51*(1+1+19+19+19+19+19+19+19+19))
// i.e. |h1| <= 1.5*2^58; narrower ranges for h3, h5, h7, h9
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
// |h0| <= 2^25
// |h4| <= 2^25
// |h1| <= 1.51*2^58
// |h5| <= 1.51*2^58
carry[1] = (h1 + (1 << 24)) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[5] = (h5 + (1 << 24)) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
// |h1| <= 2^24; from now on fits into int32
// |h5| <= 2^24; from now on fits into int32
// |h2| <= 1.21*2^59
// |h6| <= 1.21*2^59
carry[2] = (h2 + (1 << 25)) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[6] = (h6 + (1 << 25)) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
// |h2| <= 2^25; from now on fits into int32 unchanged
// |h6| <= 2^25; from now on fits into int32 unchanged
// |h3| <= 1.51*2^58
// |h7| <= 1.51*2^58
carry[3] = (h3 + (1 << 24)) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[7] = (h7 + (1 << 24)) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
// |h3| <= 2^24; from now on fits into int32 unchanged
// |h7| <= 2^24; from now on fits into int32 unchanged
// |h4| <= 1.52*2^33
// |h8| <= 1.52*2^33
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[8] = (h8 + (1 << 25)) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
// |h4| <= 2^25; from now on fits into int32 unchanged
// |h8| <= 2^25; from now on fits into int32 unchanged
// |h5| <= 1.01*2^24
// |h9| <= 1.51*2^58
carry[9] = (h9 + (1 << 24)) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
// |h9| <= 2^24; from now on fits into int32 unchanged
// |h0| <= 1.8*2^37
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
// |h0| <= 2^25; from now on fits into int32 unchanged
// |h1| <= 1.01*2^24
h[0] = int32(h0)
h[1] = int32(h1)
h[2] = int32(h2)
h[3] = int32(h3)
h[4] = int32(h4)
h[5] = int32(h5)
h[6] = int32(h6)
h[7] = int32(h7)
h[8] = int32(h8)
h[9] = int32(h9)
// It is recommended to use the X25519 function with Basepoint instead, as
// copying into fixed size arrays can lead to unexpected bugs.
func ScalarBaseMult(dst, scalar *[32]byte) {
ScalarMult(dst, scalar, &basePoint)
}
// feSquare calculates h = f*f. Can overlap h with f.
//
// Preconditions:
// |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
//
// Postconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
func feSquare(h, f *fieldElement) {
f0 := f[0]
f1 := f[1]
f2 := f[2]
f3 := f[3]
f4 := f[4]
f5 := f[5]
f6 := f[6]
f7 := f[7]
f8 := f[8]
f9 := f[9]
f0_2 := 2 * f0
f1_2 := 2 * f1
f2_2 := 2 * f2
f3_2 := 2 * f3
f4_2 := 2 * f4
f5_2 := 2 * f5
f6_2 := 2 * f6
f7_2 := 2 * f7
f5_38 := 38 * f5 // 1.31*2^30
f6_19 := 19 * f6 // 1.31*2^30
f7_38 := 38 * f7 // 1.31*2^30
f8_19 := 19 * f8 // 1.31*2^30
f9_38 := 38 * f9 // 1.31*2^30
f0f0 := int64(f0) * int64(f0)
f0f1_2 := int64(f0_2) * int64(f1)
f0f2_2 := int64(f0_2) * int64(f2)
f0f3_2 := int64(f0_2) * int64(f3)
f0f4_2 := int64(f0_2) * int64(f4)
f0f5_2 := int64(f0_2) * int64(f5)
f0f6_2 := int64(f0_2) * int64(f6)
f0f7_2 := int64(f0_2) * int64(f7)
f0f8_2 := int64(f0_2) * int64(f8)
f0f9_2 := int64(f0_2) * int64(f9)
f1f1_2 := int64(f1_2) * int64(f1)
f1f2_2 := int64(f1_2) * int64(f2)
f1f3_4 := int64(f1_2) * int64(f3_2)
f1f4_2 := int64(f1_2) * int64(f4)
f1f5_4 := int64(f1_2) * int64(f5_2)
f1f6_2 := int64(f1_2) * int64(f6)
f1f7_4 := int64(f1_2) * int64(f7_2)
f1f8_2 := int64(f1_2) * int64(f8)
f1f9_76 := int64(f1_2) * int64(f9_38)
f2f2 := int64(f2) * int64(f2)
f2f3_2 := int64(f2_2) * int64(f3)
f2f4_2 := int64(f2_2) * int64(f4)
f2f5_2 := int64(f2_2) * int64(f5)
f2f6_2 := int64(f2_2) * int64(f6)
f2f7_2 := int64(f2_2) * int64(f7)
f2f8_38 := int64(f2_2) * int64(f8_19)
f2f9_38 := int64(f2) * int64(f9_38)
f3f3_2 := int64(f3_2) * int64(f3)
f3f4_2 := int64(f3_2) * int64(f4)
f3f5_4 := int64(f3_2) * int64(f5_2)
f3f6_2 := int64(f3_2) * int64(f6)
f3f7_76 := int64(f3_2) * int64(f7_38)
f3f8_38 := int64(f3_2) * int64(f8_19)
f3f9_76 := int64(f3_2) * int64(f9_38)
f4f4 := int64(f4) * int64(f4)
f4f5_2 := int64(f4_2) * int64(f5)
f4f6_38 := int64(f4_2) * int64(f6_19)
f4f7_38 := int64(f4) * int64(f7_38)
f4f8_38 := int64(f4_2) * int64(f8_19)
f4f9_38 := int64(f4) * int64(f9_38)
f5f5_38 := int64(f5) * int64(f5_38)
f5f6_38 := int64(f5_2) * int64(f6_19)
f5f7_76 := int64(f5_2) * int64(f7_38)
f5f8_38 := int64(f5_2) * int64(f8_19)
f5f9_76 := int64(f5_2) * int64(f9_38)
f6f6_19 := int64(f6) * int64(f6_19)
f6f7_38 := int64(f6) * int64(f7_38)
f6f8_38 := int64(f6_2) * int64(f8_19)
f6f9_38 := int64(f6) * int64(f9_38)
f7f7_38 := int64(f7) * int64(f7_38)
f7f8_38 := int64(f7_2) * int64(f8_19)
f7f9_76 := int64(f7_2) * int64(f9_38)
f8f8_19 := int64(f8) * int64(f8_19)
f8f9_38 := int64(f8) * int64(f9_38)
f9f9_38 := int64(f9) * int64(f9_38)
h0 := f0f0 + f1f9_76 + f2f8_38 + f3f7_76 + f4f6_38 + f5f5_38
h1 := f0f1_2 + f2f9_38 + f3f8_38 + f4f7_38 + f5f6_38
h2 := f0f2_2 + f1f1_2 + f3f9_76 + f4f8_38 + f5f7_76 + f6f6_19
h3 := f0f3_2 + f1f2_2 + f4f9_38 + f5f8_38 + f6f7_38
h4 := f0f4_2 + f1f3_4 + f2f2 + f5f9_76 + f6f8_38 + f7f7_38
h5 := f0f5_2 + f1f4_2 + f2f3_2 + f6f9_38 + f7f8_38
h6 := f0f6_2 + f1f5_4 + f2f4_2 + f3f3_2 + f7f9_76 + f8f8_19
h7 := f0f7_2 + f1f6_2 + f2f5_2 + f3f4_2 + f8f9_38
h8 := f0f8_2 + f1f7_4 + f2f6_2 + f3f5_4 + f4f4 + f9f9_38
h9 := f0f9_2 + f1f8_2 + f2f7_2 + f3f6_2 + f4f5_2
var carry [10]int64
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[1] = (h1 + (1 << 24)) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[5] = (h5 + (1 << 24)) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
carry[2] = (h2 + (1 << 25)) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[6] = (h6 + (1 << 25)) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
carry[3] = (h3 + (1 << 24)) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[7] = (h7 + (1 << 24)) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
const (
// ScalarSize is the size of the scalar input to X25519.
ScalarSize = 32
// PointSize is the size of the point input to X25519.
PointSize = 32
)
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[8] = (h8 + (1 << 25)) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
// Basepoint is the canonical Curve25519 generator.
var Basepoint []byte
carry[9] = (h9 + (1 << 24)) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
var basePoint = [32]byte{9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
func init() { Basepoint = basePoint[:] }
h[0] = int32(h0)
h[1] = int32(h1)
h[2] = int32(h2)
h[3] = int32(h3)
h[4] = int32(h4)
h[5] = int32(h5)
h[6] = int32(h6)
h[7] = int32(h7)
h[8] = int32(h8)
h[9] = int32(h9)
func checkBasepoint() {
if subtle.ConstantTimeCompare(Basepoint, []byte{
0x09, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
}) != 1 {
panic("curve25519: global Basepoint value was modified")
}
}
// feMul121666 calculates h = f * 121666. Can overlap h with f.
// X25519 returns the result of the scalar multiplication (scalar * point),
// according to RFC 7748, Section 5. scalar, point and the return value are
// slices of 32 bytes.
//
// Preconditions:
// |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
// scalar can be generated at random, for example with crypto/rand. point should
// be either Basepoint or the output of another X25519 call.
//
// Postconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
func feMul121666(h, f *fieldElement) {
h0 := int64(f[0]) * 121666
h1 := int64(f[1]) * 121666
h2 := int64(f[2]) * 121666
h3 := int64(f[3]) * 121666
h4 := int64(f[4]) * 121666
h5 := int64(f[5]) * 121666
h6 := int64(f[6]) * 121666
h7 := int64(f[7]) * 121666
h8 := int64(f[8]) * 121666
h9 := int64(f[9]) * 121666
var carry [10]int64
carry[9] = (h9 + (1 << 24)) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
carry[1] = (h1 + (1 << 24)) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[3] = (h3 + (1 << 24)) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[5] = (h5 + (1 << 24)) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
carry[7] = (h7 + (1 << 24)) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[2] = (h2 + (1 << 25)) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[6] = (h6 + (1 << 25)) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
carry[8] = (h8 + (1 << 25)) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
h[0] = int32(h0)
h[1] = int32(h1)
h[2] = int32(h2)
h[3] = int32(h3)
h[4] = int32(h4)
h[5] = int32(h5)
h[6] = int32(h6)
h[7] = int32(h7)
h[8] = int32(h8)
h[9] = int32(h9)
// If point is Basepoint (but not if it's a different slice with the same
// contents) a precomputed implementation might be used for performance.
func X25519(scalar, point []byte) ([]byte, error) {
// Outline the body of function, to let the allocation be inlined in the
// caller, and possibly avoid escaping to the heap.
var dst [32]byte
return x25519(&dst, scalar, point)
}
// feInvert sets out = z^-1.
func feInvert(out, z *fieldElement) {
var t0, t1, t2, t3 fieldElement
var i int
feSquare(&t0, z)
for i = 1; i < 1; i++ {
feSquare(&t0, &t0)
}
feSquare(&t1, &t0)
for i = 1; i < 2; i++ {
feSquare(&t1, &t1)
}
feMul(&t1, z, &t1)
feMul(&t0, &t0, &t1)
feSquare(&t2, &t0)
for i = 1; i < 1; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t1, &t2)
feSquare(&t2, &t1)
for i = 1; i < 5; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t2, &t1)
feSquare(&t2, &t1)
for i = 1; i < 10; i++ {
feSquare(&t2, &t2)
}
feMul(&t2, &t2, &t1)
feSquare(&t3, &t2)
for i = 1; i < 20; i++ {
feSquare(&t3, &t3)
}
feMul(&t2, &t3, &t2)
feSquare(&t2, &t2)
for i = 1; i < 10; i++ {
feSquare(&t2, &t2)
func x25519(dst *[32]byte, scalar, point []byte) ([]byte, error) {
var in [32]byte
if l := len(scalar); l != 32 {
return nil, fmt.Errorf("bad scalar length: %d, expected %d", l, 32)
}
feMul(&t1, &t2, &t1)
feSquare(&t2, &t1)
for i = 1; i < 50; i++ {
feSquare(&t2, &t2)
if l := len(point); l != 32 {
return nil, fmt.Errorf("bad point length: %d, expected %d", l, 32)
}
feMul(&t2, &t2, &t1)
feSquare(&t3, &t2)
for i = 1; i < 100; i++ {
feSquare(&t3, &t3)
copy(in[:], scalar)
if &point[0] == &Basepoint[0] {
checkBasepoint()
ScalarBaseMult(dst, &in)
} else {
var base, zero [32]byte
copy(base[:], point)
ScalarMult(dst, &in, &base)
if subtle.ConstantTimeCompare(dst[:], zero[:]) == 1 {
return nil, fmt.Errorf("bad input point: low order point")
}
feMul(&t2, &t3, &t2)
feSquare(&t2, &t2)
for i = 1; i < 50; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t2, &t1)
feSquare(&t1, &t1)
for i = 1; i < 5; i++ {
feSquare(&t1, &t1)
}
feMul(out, &t1, &t0)
}
func scalarMult(out, in, base *[32]byte) {
var e [32]byte
copy(e[:], in[:])
e[0] &= 248
e[31] &= 127
e[31] |= 64
var x1, x2, z2, x3, z3, tmp0, tmp1 fieldElement
feFromBytes(&x1, base)
feOne(&x2)
feCopy(&x3, &x1)
feOne(&z3)
swap := int32(0)
for pos := 254; pos >= 0; pos-- {
b := e[pos/8] >> uint(pos&7)
b &= 1
swap ^= int32(b)
feCSwap(&x2, &x3, swap)
feCSwap(&z2, &z3, swap)
swap = int32(b)
feSub(&tmp0, &x3, &z3)
feSub(&tmp1, &x2, &z2)
feAdd(&x2, &x2, &z2)
feAdd(&z2, &x3, &z3)
feMul(&z3, &tmp0, &x2)
feMul(&z2, &z2, &tmp1)
feSquare(&tmp0, &tmp1)
feSquare(&tmp1, &x2)
feAdd(&x3, &z3, &z2)
feSub(&z2, &z3, &z2)
feMul(&x2, &tmp1, &tmp0)
feSub(&tmp1, &tmp1, &tmp0)
feSquare(&z2, &z2)
feMul121666(&z3, &tmp1)
feSquare(&x3, &x3)
feAdd(&tmp0, &tmp0, &z3)
feMul(&z3, &x1, &z2)
feMul(&z2, &tmp1, &tmp0)
}
feCSwap(&x2, &x3, swap)
feCSwap(&z2, &z3, swap)
feInvert(&z2, &z2)
feMul(&x2, &x2, &z2)
feToBytes(out, &x2)
return dst[:], nil
}
......@@ -2,7 +2,7 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build amd64,!gccgo,!appengine
// +build amd64,!gccgo,!appengine,!purego
package curve25519
......
......@@ -5,9 +5,84 @@
// This code was translated into a form compatible with 6a from the public
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// +build amd64,!gccgo,!appengine
// +build amd64,!gccgo,!appengine,!purego
#include "const_amd64.h"
#define REDMASK51 0x0007FFFFFFFFFFFF
// These constants cannot be encoded in non-MOVQ immediates.
// We access them directly from memory instead.
DATA ·_121666_213(SB)/8, $996687872
GLOBL ·_121666_213(SB), 8, $8
DATA ·_2P0(SB)/8, $0xFFFFFFFFFFFDA
GLOBL ·_2P0(SB), 8, $8
DATA ·_2P1234(SB)/8, $0xFFFFFFFFFFFFE
GLOBL ·_2P1234(SB), 8, $8
// func freeze(inout *[5]uint64)
TEXT ·freeze(SB),7,$0-8
MOVQ inout+0(FP), DI
MOVQ 0(DI),SI
MOVQ 8(DI),DX
MOVQ 16(DI),CX
MOVQ 24(DI),R8
MOVQ 32(DI),R9
MOVQ $REDMASK51,AX
MOVQ AX,R10
SUBQ $18,R10
MOVQ $3,R11
REDUCELOOP:
MOVQ SI,R12
SHRQ $51,R12
ANDQ AX,SI
ADDQ R12,DX
MOVQ DX,R12
SHRQ $51,R12
ANDQ AX,DX
ADDQ R12,CX
MOVQ CX,R12
SHRQ $51,R12
ANDQ AX,CX
ADDQ R12,R8
MOVQ R8,R12
SHRQ $51,R12
ANDQ AX,R8
ADDQ R12,R9
MOVQ R9,R12
SHRQ $51,R12
ANDQ AX,R9
IMUL3Q $19,R12,R12
ADDQ R12,SI
SUBQ $1,R11
JA REDUCELOOP
MOVQ $1,R12
CMPQ R10,SI
CMOVQLT R11,R12
CMPQ AX,DX
CMOVQNE R11,R12
CMPQ AX,CX
CMOVQNE R11,R12
CMPQ AX,R8
CMOVQNE R11,R12
CMPQ AX,R9
CMOVQNE R11,R12
NEGQ R12
ANDQ R12,AX
ANDQ R12,R10
SUBQ R10,SI
SUBQ AX,DX
SUBQ AX,CX
SUBQ AX,R8
SUBQ AX,R9
MOVQ SI,0(DI)
MOVQ DX,8(DI)
MOVQ CX,16(DI)
MOVQ R8,24(DI)
MOVQ R9,32(DI)
RET
// func ladderstep(inout *[5][5]uint64)
TEXT ·ladderstep(SB),0,$296-8
......@@ -1375,3 +1450,344 @@ TEXT ·ladderstep(SB),0,$296-8
MOVQ AX,104(DI)
MOVQ R10,112(DI)
RET
// func cswap(inout *[4][5]uint64, v uint64)
TEXT ·cswap(SB),7,$0
MOVQ inout+0(FP),DI
MOVQ v+8(FP),SI
SUBQ $1, SI
NOTQ SI
MOVQ SI, X15
PSHUFD $0x44, X15, X15
MOVOU 0(DI), X0
MOVOU 16(DI), X2
MOVOU 32(DI), X4
MOVOU 48(DI), X6
MOVOU 64(DI), X8
MOVOU 80(DI), X1
MOVOU 96(DI), X3
MOVOU 112(DI), X5
MOVOU 128(DI), X7
MOVOU 144(DI), X9
MOVO X1, X10
MOVO X3, X11
MOVO X5, X12
MOVO X7, X13
MOVO X9, X14
PXOR X0, X10
PXOR X2, X11
PXOR X4, X12
PXOR X6, X13
PXOR X8, X14
PAND X15, X10
PAND X15, X11
PAND X15, X12
PAND X15, X13
PAND X15, X14
PXOR X10, X0
PXOR X10, X1
PXOR X11, X2
PXOR X11, X3
PXOR X12, X4
PXOR X12, X5
PXOR X13, X6
PXOR X13, X7
PXOR X14, X8
PXOR X14, X9
MOVOU X0, 0(DI)
MOVOU X2, 16(DI)
MOVOU X4, 32(DI)
MOVOU X6, 48(DI)
MOVOU X8, 64(DI)
MOVOU X1, 80(DI)
MOVOU X3, 96(DI)
MOVOU X5, 112(DI)
MOVOU X7, 128(DI)
MOVOU X9, 144(DI)
RET
// func mul(dest, a, b *[5]uint64)
TEXT ·mul(SB),0,$16-24
MOVQ dest+0(FP), DI
MOVQ a+8(FP), SI
MOVQ b+16(FP), DX
MOVQ DX,CX
MOVQ 24(SI),DX
IMUL3Q $19,DX,AX
MOVQ AX,0(SP)
MULQ 16(CX)
MOVQ AX,R8
MOVQ DX,R9
MOVQ 32(SI),DX
IMUL3Q $19,DX,AX
MOVQ AX,8(SP)
MULQ 8(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 0(SI),AX
MULQ 0(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 0(SI),AX
MULQ 8(CX)
MOVQ AX,R10
MOVQ DX,R11
MOVQ 0(SI),AX
MULQ 16(CX)
MOVQ AX,R12
MOVQ DX,R13
MOVQ 0(SI),AX
MULQ 24(CX)
MOVQ AX,R14
MOVQ DX,R15
MOVQ 0(SI),AX
MULQ 32(CX)
MOVQ AX,BX
MOVQ DX,BP
MOVQ 8(SI),AX
MULQ 0(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 8(SI),AX
MULQ 8(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 8(SI),AX
MULQ 16(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ 8(SI),AX
MULQ 24(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 8(SI),DX
IMUL3Q $19,DX,AX
MULQ 32(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 16(SI),AX
MULQ 0(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 16(SI),AX
MULQ 8(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ 16(SI),AX
MULQ 16(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 16(SI),DX
IMUL3Q $19,DX,AX
MULQ 24(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 16(SI),DX
IMUL3Q $19,DX,AX
MULQ 32(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 24(SI),AX
MULQ 0(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ 24(SI),AX
MULQ 8(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 0(SP),AX
MULQ 24(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 0(SP),AX
MULQ 32(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 32(SI),AX
MULQ 0(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 8(SP),AX
MULQ 16(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 8(SP),AX
MULQ 24(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 8(SP),AX
MULQ 32(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ $REDMASK51,SI
SHLQ $13,R8,R9
ANDQ SI,R8
SHLQ $13,R10,R11
ANDQ SI,R10
ADDQ R9,R10
SHLQ $13,R12,R13
ANDQ SI,R12
ADDQ R11,R12
SHLQ $13,R14,R15
ANDQ SI,R14
ADDQ R13,R14
SHLQ $13,BX,BP
ANDQ SI,BX
ADDQ R15,BX
IMUL3Q $19,BP,DX
ADDQ DX,R8
MOVQ R8,DX
SHRQ $51,DX
ADDQ R10,DX
MOVQ DX,CX
SHRQ $51,DX
ANDQ SI,R8
ADDQ R12,DX
MOVQ DX,R9
SHRQ $51,DX
ANDQ SI,CX
ADDQ R14,DX
MOVQ DX,AX
SHRQ $51,DX
ANDQ SI,R9
ADDQ BX,DX
MOVQ DX,R10
SHRQ $51,DX
ANDQ SI,AX
IMUL3Q $19,DX,DX
ADDQ DX,R8
ANDQ SI,R10
MOVQ R8,0(DI)
MOVQ CX,8(DI)
MOVQ R9,16(DI)
MOVQ AX,24(DI)
MOVQ R10,32(DI)
RET
// func square(out, in *[5]uint64)
TEXT ·square(SB),7,$0-16
MOVQ out+0(FP), DI
MOVQ in+8(FP), SI
MOVQ 0(SI),AX
MULQ 0(SI)
MOVQ AX,CX
MOVQ DX,R8
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 8(SI)
MOVQ AX,R9
MOVQ DX,R10
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 16(SI)
MOVQ AX,R11
MOVQ DX,R12
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 24(SI)
MOVQ AX,R13
MOVQ DX,R14
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 32(SI)
MOVQ AX,R15
MOVQ DX,BX
MOVQ 8(SI),AX
MULQ 8(SI)
ADDQ AX,R11
ADCQ DX,R12
MOVQ 8(SI),AX
SHLQ $1,AX
MULQ 16(SI)
ADDQ AX,R13
ADCQ DX,R14
MOVQ 8(SI),AX
SHLQ $1,AX
MULQ 24(SI)
ADDQ AX,R15
ADCQ DX,BX
MOVQ 8(SI),DX
IMUL3Q $38,DX,AX
MULQ 32(SI)
ADDQ AX,CX
ADCQ DX,R8
MOVQ 16(SI),AX
MULQ 16(SI)
ADDQ AX,R15
ADCQ DX,BX
MOVQ 16(SI),DX
IMUL3Q $38,DX,AX
MULQ 24(SI)
ADDQ AX,CX
ADCQ DX,R8
MOVQ 16(SI),DX
IMUL3Q $38,DX,AX
MULQ 32(SI)
ADDQ AX,R9
ADCQ DX,R10
MOVQ 24(SI),DX
IMUL3Q $19,DX,AX
MULQ 24(SI)
ADDQ AX,R9
ADCQ DX,R10
MOVQ 24(SI),DX
IMUL3Q $38,DX,AX
MULQ 32(SI)
ADDQ AX,R11
ADCQ DX,R12
MOVQ 32(SI),DX
IMUL3Q $19,DX,AX
MULQ 32(SI)
ADDQ AX,R13
ADCQ DX,R14
MOVQ $REDMASK51,SI
SHLQ $13,CX,R8
ANDQ SI,CX
SHLQ $13,R9,R10
ANDQ SI,R9
ADDQ R8,R9
SHLQ $13,R11,R12
ANDQ SI,R11
ADDQ R10,R11
SHLQ $13,R13,R14
ANDQ SI,R13
ADDQ R12,R13
SHLQ $13,R15,BX
ANDQ SI,R15
ADDQ R14,R15
IMUL3Q $19,BX,DX
ADDQ DX,CX
MOVQ CX,DX
SHRQ $51,DX
ADDQ R9,DX
ANDQ SI,CX
MOVQ DX,R8
SHRQ $51,DX
ADDQ R11,DX
ANDQ SI,R8
MOVQ DX,R9
SHRQ $51,DX
ADDQ R13,DX
ANDQ SI,R9
MOVQ DX,AX
SHRQ $51,DX
ADDQ R15,DX
ANDQ SI,AX
MOVQ DX,R10
SHRQ $51,DX
IMUL3Q $19,DX,DX
ADDQ DX,CX
ANDQ SI,R10
MOVQ CX,0(DI)
MOVQ R8,8(DI)
MOVQ R9,16(DI)
MOVQ AX,24(DI)
MOVQ R10,32(DI)
RET
// Copyright 2013 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.
package curve25519
import "encoding/binary"
// This code is a port of the public domain, "ref10" implementation of
// curve25519 from SUPERCOP 20130419 by D. J. Bernstein.
// fieldElement represents an element of the field GF(2^255 - 19). An element
// t, entries t[0]...t[9], represents the integer t[0]+2^26 t[1]+2^51 t[2]+2^77
// t[3]+2^102 t[4]+...+2^230 t[9]. Bounds on each t[i] vary depending on
// context.
type fieldElement [10]int32
func feZero(fe *fieldElement) {
for i := range fe {
fe[i] = 0
}
}
func feOne(fe *fieldElement) {
feZero(fe)
fe[0] = 1
}
func feAdd(dst, a, b *fieldElement) {
for i := range dst {
dst[i] = a[i] + b[i]
}
}
func feSub(dst, a, b *fieldElement) {
for i := range dst {
dst[i] = a[i] - b[i]
}
}
func feCopy(dst, src *fieldElement) {
for i := range dst {
dst[i] = src[i]
}
}
// feCSwap replaces (f,g) with (g,f) if b == 1; replaces (f,g) with (f,g) if b == 0.
//
// Preconditions: b in {0,1}.
func feCSwap(f, g *fieldElement, b int32) {
b = -b
for i := range f {
t := b & (f[i] ^ g[i])
f[i] ^= t
g[i] ^= t
}
}
// load3 reads a 24-bit, little-endian value from in.
func load3(in []byte) int64 {
var r int64
r = int64(in[0])
r |= int64(in[1]) << 8
r |= int64(in[2]) << 16
return r
}
// load4 reads a 32-bit, little-endian value from in.
func load4(in []byte) int64 {
return int64(binary.LittleEndian.Uint32(in))
}
func feFromBytes(dst *fieldElement, src *[32]byte) {
h0 := load4(src[:])
h1 := load3(src[4:]) << 6
h2 := load3(src[7:]) << 5
h3 := load3(src[10:]) << 3
h4 := load3(src[13:]) << 2
h5 := load4(src[16:])
h6 := load3(src[20:]) << 7
h7 := load3(src[23:]) << 5
h8 := load3(src[26:]) << 4
h9 := (load3(src[29:]) & 0x7fffff) << 2
var carry [10]int64
carry[9] = (h9 + 1<<24) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
carry[1] = (h1 + 1<<24) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[3] = (h3 + 1<<24) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[5] = (h5 + 1<<24) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
carry[7] = (h7 + 1<<24) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
carry[0] = (h0 + 1<<25) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[2] = (h2 + 1<<25) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[4] = (h4 + 1<<25) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[6] = (h6 + 1<<25) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
carry[8] = (h8 + 1<<25) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
dst[0] = int32(h0)
dst[1] = int32(h1)
dst[2] = int32(h2)
dst[3] = int32(h3)
dst[4] = int32(h4)
dst[5] = int32(h5)
dst[6] = int32(h6)
dst[7] = int32(h7)
dst[8] = int32(h8)
dst[9] = int32(h9)
}
// feToBytes marshals h to s.
// Preconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
//
// Write p=2^255-19; q=floor(h/p).
// Basic claim: q = floor(2^(-255)(h + 19 2^(-25)h9 + 2^(-1))).
//
// Proof:
// Have |h|<=p so |q|<=1 so |19^2 2^(-255) q|<1/4.
// Also have |h-2^230 h9|<2^230 so |19 2^(-255)(h-2^230 h9)|<1/4.
//
// Write y=2^(-1)-19^2 2^(-255)q-19 2^(-255)(h-2^230 h9).
// Then 0<y<1.
//
// Write r=h-pq.
// Have 0<=r<=p-1=2^255-20.
// Thus 0<=r+19(2^-255)r<r+19(2^-255)2^255<=2^255-1.
//
// Write x=r+19(2^-255)r+y.
// Then 0<x<2^255 so floor(2^(-255)x) = 0 so floor(q+2^(-255)x) = q.
//
// Have q+2^(-255)x = 2^(-255)(h + 19 2^(-25) h9 + 2^(-1))
// so floor(2^(-255)(h + 19 2^(-25) h9 + 2^(-1))) = q.
func feToBytes(s *[32]byte, h *fieldElement) {
var carry [10]int32
q := (19*h[9] + (1 << 24)) >> 25
q = (h[0] + q) >> 26
q = (h[1] + q) >> 25
q = (h[2] + q) >> 26
q = (h[3] + q) >> 25
q = (h[4] + q) >> 26
q = (h[5] + q) >> 25
q = (h[6] + q) >> 26
q = (h[7] + q) >> 25
q = (h[8] + q) >> 26
q = (h[9] + q) >> 25
// Goal: Output h-(2^255-19)q, which is between 0 and 2^255-20.
h[0] += 19 * q
// Goal: Output h-2^255 q, which is between 0 and 2^255-20.
carry[0] = h[0] >> 26
h[1] += carry[0]
h[0] -= carry[0] << 26
carry[1] = h[1] >> 25
h[2] += carry[1]
h[1] -= carry[1] << 25
carry[2] = h[2] >> 26
h[3] += carry[2]
h[2] -= carry[2] << 26
carry[3] = h[3] >> 25
h[4] += carry[3]
h[3] -= carry[3] << 25
carry[4] = h[4] >> 26
h[5] += carry[4]
h[4] -= carry[4] << 26
carry[5] = h[5] >> 25
h[6] += carry[5]
h[5] -= carry[5] << 25
carry[6] = h[6] >> 26
h[7] += carry[6]
h[6] -= carry[6] << 26
carry[7] = h[7] >> 25
h[8] += carry[7]
h[7] -= carry[7] << 25
carry[8] = h[8] >> 26
h[9] += carry[8]
h[8] -= carry[8] << 26
carry[9] = h[9] >> 25
h[9] -= carry[9] << 25
// h10 = carry9
// Goal: Output h[0]+...+2^255 h10-2^255 q, which is between 0 and 2^255-20.
// Have h[0]+...+2^230 h[9] between 0 and 2^255-1;
// evidently 2^255 h10-2^255 q = 0.
// Goal: Output h[0]+...+2^230 h[9].
s[0] = byte(h[0] >> 0)
s[1] = byte(h[0] >> 8)
s[2] = byte(h[0] >> 16)
s[3] = byte((h[0] >> 24) | (h[1] << 2))
s[4] = byte(h[1] >> 6)
s[5] = byte(h[1] >> 14)
s[6] = byte((h[1] >> 22) | (h[2] << 3))
s[7] = byte(h[2] >> 5)
s[8] = byte(h[2] >> 13)
s[9] = byte((h[2] >> 21) | (h[3] << 5))
s[10] = byte(h[3] >> 3)
s[11] = byte(h[3] >> 11)
s[12] = byte((h[3] >> 19) | (h[4] << 6))
s[13] = byte(h[4] >> 2)
s[14] = byte(h[4] >> 10)
s[15] = byte(h[4] >> 18)
s[16] = byte(h[5] >> 0)
s[17] = byte(h[5] >> 8)
s[18] = byte(h[5] >> 16)
s[19] = byte((h[5] >> 24) | (h[6] << 1))
s[20] = byte(h[6] >> 7)
s[21] = byte(h[6] >> 15)
s[22] = byte((h[6] >> 23) | (h[7] << 3))
s[23] = byte(h[7] >> 5)
s[24] = byte(h[7] >> 13)
s[25] = byte((h[7] >> 21) | (h[8] << 4))
s[26] = byte(h[8] >> 4)
s[27] = byte(h[8] >> 12)
s[28] = byte((h[8] >> 20) | (h[9] << 6))
s[29] = byte(h[9] >> 2)
s[30] = byte(h[9] >> 10)
s[31] = byte(h[9] >> 18)
}
// feMul calculates h = f * g
// Can overlap h with f or g.
//
// Preconditions:
// |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
// |g| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
//
// Postconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
//
// Notes on implementation strategy:
//
// Using schoolbook multiplication.
// Karatsuba would save a little in some cost models.
//
// Most multiplications by 2 and 19 are 32-bit precomputations;
// cheaper than 64-bit postcomputations.
//
// There is one remaining multiplication by 19 in the carry chain;
// one *19 precomputation can be merged into this,
// but the resulting data flow is considerably less clean.
//
// There are 12 carries below.
// 10 of them are 2-way parallelizable and vectorizable.
// Can get away with 11 carries, but then data flow is much deeper.
//
// With tighter constraints on inputs can squeeze carries into int32.
func feMul(h, f, g *fieldElement) {
f0 := f[0]
f1 := f[1]
f2 := f[2]
f3 := f[3]
f4 := f[4]
f5 := f[5]
f6 := f[6]
f7 := f[7]
f8 := f[8]
f9 := f[9]
g0 := g[0]
g1 := g[1]
g2 := g[2]
g3 := g[3]
g4 := g[4]
g5 := g[5]
g6 := g[6]
g7 := g[7]
g8 := g[8]
g9 := g[9]
g1_19 := 19 * g1 // 1.4*2^29
g2_19 := 19 * g2 // 1.4*2^30; still ok
g3_19 := 19 * g3
g4_19 := 19 * g4
g5_19 := 19 * g5
g6_19 := 19 * g6
g7_19 := 19 * g7
g8_19 := 19 * g8
g9_19 := 19 * g9
f1_2 := 2 * f1
f3_2 := 2 * f3
f5_2 := 2 * f5
f7_2 := 2 * f7
f9_2 := 2 * f9
f0g0 := int64(f0) * int64(g0)
f0g1 := int64(f0) * int64(g1)
f0g2 := int64(f0) * int64(g2)
f0g3 := int64(f0) * int64(g3)
f0g4 := int64(f0) * int64(g4)
f0g5 := int64(f0) * int64(g5)
f0g6 := int64(f0) * int64(g6)
f0g7 := int64(f0) * int64(g7)
f0g8 := int64(f0) * int64(g8)
f0g9 := int64(f0) * int64(g9)
f1g0 := int64(f1) * int64(g0)
f1g1_2 := int64(f1_2) * int64(g1)
f1g2 := int64(f1) * int64(g2)
f1g3_2 := int64(f1_2) * int64(g3)
f1g4 := int64(f1) * int64(g4)
f1g5_2 := int64(f1_2) * int64(g5)
f1g6 := int64(f1) * int64(g6)
f1g7_2 := int64(f1_2) * int64(g7)
f1g8 := int64(f1) * int64(g8)
f1g9_38 := int64(f1_2) * int64(g9_19)
f2g0 := int64(f2) * int64(g0)
f2g1 := int64(f2) * int64(g1)
f2g2 := int64(f2) * int64(g2)
f2g3 := int64(f2) * int64(g3)
f2g4 := int64(f2) * int64(g4)
f2g5 := int64(f2) * int64(g5)
f2g6 := int64(f2) * int64(g6)
f2g7 := int64(f2) * int64(g7)
f2g8_19 := int64(f2) * int64(g8_19)
f2g9_19 := int64(f2) * int64(g9_19)
f3g0 := int64(f3) * int64(g0)
f3g1_2 := int64(f3_2) * int64(g1)
f3g2 := int64(f3) * int64(g2)
f3g3_2 := int64(f3_2) * int64(g3)
f3g4 := int64(f3) * int64(g4)
f3g5_2 := int64(f3_2) * int64(g5)
f3g6 := int64(f3) * int64(g6)
f3g7_38 := int64(f3_2) * int64(g7_19)
f3g8_19 := int64(f3) * int64(g8_19)
f3g9_38 := int64(f3_2) * int64(g9_19)
f4g0 := int64(f4) * int64(g0)
f4g1 := int64(f4) * int64(g1)
f4g2 := int64(f4) * int64(g2)
f4g3 := int64(f4) * int64(g3)
f4g4 := int64(f4) * int64(g4)
f4g5 := int64(f4) * int64(g5)
f4g6_19 := int64(f4) * int64(g6_19)
f4g7_19 := int64(f4) * int64(g7_19)
f4g8_19 := int64(f4) * int64(g8_19)
f4g9_19 := int64(f4) * int64(g9_19)
f5g0 := int64(f5) * int64(g0)
f5g1_2 := int64(f5_2) * int64(g1)
f5g2 := int64(f5) * int64(g2)
f5g3_2 := int64(f5_2) * int64(g3)
f5g4 := int64(f5) * int64(g4)
f5g5_38 := int64(f5_2) * int64(g5_19)
f5g6_19 := int64(f5) * int64(g6_19)
f5g7_38 := int64(f5_2) * int64(g7_19)
f5g8_19 := int64(f5) * int64(g8_19)
f5g9_38 := int64(f5_2) * int64(g9_19)
f6g0 := int64(f6) * int64(g0)
f6g1 := int64(f6) * int64(g1)
f6g2 := int64(f6) * int64(g2)
f6g3 := int64(f6) * int64(g3)
f6g4_19 := int64(f6) * int64(g4_19)
f6g5_19 := int64(f6) * int64(g5_19)
f6g6_19 := int64(f6) * int64(g6_19)
f6g7_19 := int64(f6) * int64(g7_19)
f6g8_19 := int64(f6) * int64(g8_19)
f6g9_19 := int64(f6) * int64(g9_19)
f7g0 := int64(f7) * int64(g0)
f7g1_2 := int64(f7_2) * int64(g1)
f7g2 := int64(f7) * int64(g2)
f7g3_38 := int64(f7_2) * int64(g3_19)
f7g4_19 := int64(f7) * int64(g4_19)
f7g5_38 := int64(f7_2) * int64(g5_19)
f7g6_19 := int64(f7) * int64(g6_19)
f7g7_38 := int64(f7_2) * int64(g7_19)
f7g8_19 := int64(f7) * int64(g8_19)
f7g9_38 := int64(f7_2) * int64(g9_19)
f8g0 := int64(f8) * int64(g0)
f8g1 := int64(f8) * int64(g1)
f8g2_19 := int64(f8) * int64(g2_19)
f8g3_19 := int64(f8) * int64(g3_19)
f8g4_19 := int64(f8) * int64(g4_19)
f8g5_19 := int64(f8) * int64(g5_19)
f8g6_19 := int64(f8) * int64(g6_19)
f8g7_19 := int64(f8) * int64(g7_19)
f8g8_19 := int64(f8) * int64(g8_19)
f8g9_19 := int64(f8) * int64(g9_19)
f9g0 := int64(f9) * int64(g0)
f9g1_38 := int64(f9_2) * int64(g1_19)
f9g2_19 := int64(f9) * int64(g2_19)
f9g3_38 := int64(f9_2) * int64(g3_19)
f9g4_19 := int64(f9) * int64(g4_19)
f9g5_38 := int64(f9_2) * int64(g5_19)
f9g6_19 := int64(f9) * int64(g6_19)
f9g7_38 := int64(f9_2) * int64(g7_19)
f9g8_19 := int64(f9) * int64(g8_19)
f9g9_38 := int64(f9_2) * int64(g9_19)
h0 := f0g0 + f1g9_38 + f2g8_19 + f3g7_38 + f4g6_19 + f5g5_38 + f6g4_19 + f7g3_38 + f8g2_19 + f9g1_38
h1 := f0g1 + f1g0 + f2g9_19 + f3g8_19 + f4g7_19 + f5g6_19 + f6g5_19 + f7g4_19 + f8g3_19 + f9g2_19
h2 := f0g2 + f1g1_2 + f2g0 + f3g9_38 + f4g8_19 + f5g7_38 + f6g6_19 + f7g5_38 + f8g4_19 + f9g3_38
h3 := f0g3 + f1g2 + f2g1 + f3g0 + f4g9_19 + f5g8_19 + f6g7_19 + f7g6_19 + f8g5_19 + f9g4_19
h4 := f0g4 + f1g3_2 + f2g2 + f3g1_2 + f4g0 + f5g9_38 + f6g8_19 + f7g7_38 + f8g6_19 + f9g5_38
h5 := f0g5 + f1g4 + f2g3 + f3g2 + f4g1 + f5g0 + f6g9_19 + f7g8_19 + f8g7_19 + f9g6_19
h6 := f0g6 + f1g5_2 + f2g4 + f3g3_2 + f4g2 + f5g1_2 + f6g0 + f7g9_38 + f8g8_19 + f9g7_38
h7 := f0g7 + f1g6 + f2g5 + f3g4 + f4g3 + f5g2 + f6g1 + f7g0 + f8g9_19 + f9g8_19
h8 := f0g8 + f1g7_2 + f2g6 + f3g5_2 + f4g4 + f5g3_2 + f6g2 + f7g1_2 + f8g0 + f9g9_38
h9 := f0g9 + f1g8 + f2g7 + f3g6 + f4g5 + f5g4 + f6g3 + f7g2 + f8g1 + f9g0
var carry [10]int64
// |h0| <= (1.1*1.1*2^52*(1+19+19+19+19)+1.1*1.1*2^50*(38+38+38+38+38))
// i.e. |h0| <= 1.2*2^59; narrower ranges for h2, h4, h6, h8
// |h1| <= (1.1*1.1*2^51*(1+1+19+19+19+19+19+19+19+19))
// i.e. |h1| <= 1.5*2^58; narrower ranges for h3, h5, h7, h9
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
// |h0| <= 2^25
// |h4| <= 2^25
// |h1| <= 1.51*2^58
// |h5| <= 1.51*2^58
carry[1] = (h1 + (1 << 24)) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[5] = (h5 + (1 << 24)) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
// |h1| <= 2^24; from now on fits into int32
// |h5| <= 2^24; from now on fits into int32
// |h2| <= 1.21*2^59
// |h6| <= 1.21*2^59
carry[2] = (h2 + (1 << 25)) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[6] = (h6 + (1 << 25)) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
// |h2| <= 2^25; from now on fits into int32 unchanged
// |h6| <= 2^25; from now on fits into int32 unchanged
// |h3| <= 1.51*2^58
// |h7| <= 1.51*2^58
carry[3] = (h3 + (1 << 24)) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[7] = (h7 + (1 << 24)) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
// |h3| <= 2^24; from now on fits into int32 unchanged
// |h7| <= 2^24; from now on fits into int32 unchanged
// |h4| <= 1.52*2^33
// |h8| <= 1.52*2^33
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[8] = (h8 + (1 << 25)) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
// |h4| <= 2^25; from now on fits into int32 unchanged
// |h8| <= 2^25; from now on fits into int32 unchanged
// |h5| <= 1.01*2^24
// |h9| <= 1.51*2^58
carry[9] = (h9 + (1 << 24)) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
// |h9| <= 2^24; from now on fits into int32 unchanged
// |h0| <= 1.8*2^37
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
// |h0| <= 2^25; from now on fits into int32 unchanged
// |h1| <= 1.01*2^24
h[0] = int32(h0)
h[1] = int32(h1)
h[2] = int32(h2)
h[3] = int32(h3)
h[4] = int32(h4)
h[5] = int32(h5)
h[6] = int32(h6)
h[7] = int32(h7)
h[8] = int32(h8)
h[9] = int32(h9)
}
// feSquare calculates h = f*f. Can overlap h with f.
//
// Preconditions:
// |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
//
// Postconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
func feSquare(h, f *fieldElement) {
f0 := f[0]
f1 := f[1]
f2 := f[2]
f3 := f[3]
f4 := f[4]
f5 := f[5]
f6 := f[6]
f7 := f[7]
f8 := f[8]
f9 := f[9]
f0_2 := 2 * f0
f1_2 := 2 * f1
f2_2 := 2 * f2
f3_2 := 2 * f3
f4_2 := 2 * f4
f5_2 := 2 * f5
f6_2 := 2 * f6
f7_2 := 2 * f7
f5_38 := 38 * f5 // 1.31*2^30
f6_19 := 19 * f6 // 1.31*2^30
f7_38 := 38 * f7 // 1.31*2^30
f8_19 := 19 * f8 // 1.31*2^30
f9_38 := 38 * f9 // 1.31*2^30
f0f0 := int64(f0) * int64(f0)
f0f1_2 := int64(f0_2) * int64(f1)
f0f2_2 := int64(f0_2) * int64(f2)
f0f3_2 := int64(f0_2) * int64(f3)
f0f4_2 := int64(f0_2) * int64(f4)
f0f5_2 := int64(f0_2) * int64(f5)
f0f6_2 := int64(f0_2) * int64(f6)
f0f7_2 := int64(f0_2) * int64(f7)
f0f8_2 := int64(f0_2) * int64(f8)
f0f9_2 := int64(f0_2) * int64(f9)
f1f1_2 := int64(f1_2) * int64(f1)
f1f2_2 := int64(f1_2) * int64(f2)
f1f3_4 := int64(f1_2) * int64(f3_2)
f1f4_2 := int64(f1_2) * int64(f4)
f1f5_4 := int64(f1_2) * int64(f5_2)
f1f6_2 := int64(f1_2) * int64(f6)
f1f7_4 := int64(f1_2) * int64(f7_2)
f1f8_2 := int64(f1_2) * int64(f8)
f1f9_76 := int64(f1_2) * int64(f9_38)
f2f2 := int64(f2) * int64(f2)
f2f3_2 := int64(f2_2) * int64(f3)
f2f4_2 := int64(f2_2) * int64(f4)
f2f5_2 := int64(f2_2) * int64(f5)
f2f6_2 := int64(f2_2) * int64(f6)
f2f7_2 := int64(f2_2) * int64(f7)
f2f8_38 := int64(f2_2) * int64(f8_19)
f2f9_38 := int64(f2) * int64(f9_38)
f3f3_2 := int64(f3_2) * int64(f3)
f3f4_2 := int64(f3_2) * int64(f4)
f3f5_4 := int64(f3_2) * int64(f5_2)
f3f6_2 := int64(f3_2) * int64(f6)
f3f7_76 := int64(f3_2) * int64(f7_38)
f3f8_38 := int64(f3_2) * int64(f8_19)
f3f9_76 := int64(f3_2) * int64(f9_38)
f4f4 := int64(f4) * int64(f4)
f4f5_2 := int64(f4_2) * int64(f5)
f4f6_38 := int64(f4_2) * int64(f6_19)
f4f7_38 := int64(f4) * int64(f7_38)
f4f8_38 := int64(f4_2) * int64(f8_19)
f4f9_38 := int64(f4) * int64(f9_38)
f5f5_38 := int64(f5) * int64(f5_38)
f5f6_38 := int64(f5_2) * int64(f6_19)
f5f7_76 := int64(f5_2) * int64(f7_38)
f5f8_38 := int64(f5_2) * int64(f8_19)
f5f9_76 := int64(f5_2) * int64(f9_38)
f6f6_19 := int64(f6) * int64(f6_19)
f6f7_38 := int64(f6) * int64(f7_38)
f6f8_38 := int64(f6_2) * int64(f8_19)
f6f9_38 := int64(f6) * int64(f9_38)
f7f7_38 := int64(f7) * int64(f7_38)
f7f8_38 := int64(f7_2) * int64(f8_19)
f7f9_76 := int64(f7_2) * int64(f9_38)
f8f8_19 := int64(f8) * int64(f8_19)
f8f9_38 := int64(f8) * int64(f9_38)
f9f9_38 := int64(f9) * int64(f9_38)
h0 := f0f0 + f1f9_76 + f2f8_38 + f3f7_76 + f4f6_38 + f5f5_38
h1 := f0f1_2 + f2f9_38 + f3f8_38 + f4f7_38 + f5f6_38
h2 := f0f2_2 + f1f1_2 + f3f9_76 + f4f8_38 + f5f7_76 + f6f6_19
h3 := f0f3_2 + f1f2_2 + f4f9_38 + f5f8_38 + f6f7_38
h4 := f0f4_2 + f1f3_4 + f2f2 + f5f9_76 + f6f8_38 + f7f7_38
h5 := f0f5_2 + f1f4_2 + f2f3_2 + f6f9_38 + f7f8_38
h6 := f0f6_2 + f1f5_4 + f2f4_2 + f3f3_2 + f7f9_76 + f8f8_19
h7 := f0f7_2 + f1f6_2 + f2f5_2 + f3f4_2 + f8f9_38
h8 := f0f8_2 + f1f7_4 + f2f6_2 + f3f5_4 + f4f4 + f9f9_38
h9 := f0f9_2 + f1f8_2 + f2f7_2 + f3f6_2 + f4f5_2
var carry [10]int64
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[1] = (h1 + (1 << 24)) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[5] = (h5 + (1 << 24)) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
carry[2] = (h2 + (1 << 25)) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[6] = (h6 + (1 << 25)) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
carry[3] = (h3 + (1 << 24)) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[7] = (h7 + (1 << 24)) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[8] = (h8 + (1 << 25)) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
carry[9] = (h9 + (1 << 24)) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
h[0] = int32(h0)
h[1] = int32(h1)
h[2] = int32(h2)
h[3] = int32(h3)
h[4] = int32(h4)
h[5] = int32(h5)
h[6] = int32(h6)
h[7] = int32(h7)
h[8] = int32(h8)
h[9] = int32(h9)
}
// feMul121666 calculates h = f * 121666. Can overlap h with f.
//
// Preconditions:
// |f| bounded by 1.1*2^26,1.1*2^25,1.1*2^26,1.1*2^25,etc.
//
// Postconditions:
// |h| bounded by 1.1*2^25,1.1*2^24,1.1*2^25,1.1*2^24,etc.
func feMul121666(h, f *fieldElement) {
h0 := int64(f[0]) * 121666
h1 := int64(f[1]) * 121666
h2 := int64(f[2]) * 121666
h3 := int64(f[3]) * 121666
h4 := int64(f[4]) * 121666
h5 := int64(f[5]) * 121666
h6 := int64(f[6]) * 121666
h7 := int64(f[7]) * 121666
h8 := int64(f[8]) * 121666
h9 := int64(f[9]) * 121666
var carry [10]int64
carry[9] = (h9 + (1 << 24)) >> 25
h0 += carry[9] * 19
h9 -= carry[9] << 25
carry[1] = (h1 + (1 << 24)) >> 25
h2 += carry[1]
h1 -= carry[1] << 25
carry[3] = (h3 + (1 << 24)) >> 25
h4 += carry[3]
h3 -= carry[3] << 25
carry[5] = (h5 + (1 << 24)) >> 25
h6 += carry[5]
h5 -= carry[5] << 25
carry[7] = (h7 + (1 << 24)) >> 25
h8 += carry[7]
h7 -= carry[7] << 25
carry[0] = (h0 + (1 << 25)) >> 26
h1 += carry[0]
h0 -= carry[0] << 26
carry[2] = (h2 + (1 << 25)) >> 26
h3 += carry[2]
h2 -= carry[2] << 26
carry[4] = (h4 + (1 << 25)) >> 26
h5 += carry[4]
h4 -= carry[4] << 26
carry[6] = (h6 + (1 << 25)) >> 26
h7 += carry[6]
h6 -= carry[6] << 26
carry[8] = (h8 + (1 << 25)) >> 26
h9 += carry[8]
h8 -= carry[8] << 26
h[0] = int32(h0)
h[1] = int32(h1)
h[2] = int32(h2)
h[3] = int32(h3)
h[4] = int32(h4)
h[5] = int32(h5)
h[6] = int32(h6)
h[7] = int32(h7)
h[8] = int32(h8)
h[9] = int32(h9)
}
// feInvert sets out = z^-1.
func feInvert(out, z *fieldElement) {
var t0, t1, t2, t3 fieldElement
var i int
feSquare(&t0, z)
for i = 1; i < 1; i++ {
feSquare(&t0, &t0)
}
feSquare(&t1, &t0)
for i = 1; i < 2; i++ {
feSquare(&t1, &t1)
}
feMul(&t1, z, &t1)
feMul(&t0, &t0, &t1)
feSquare(&t2, &t0)
for i = 1; i < 1; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t1, &t2)
feSquare(&t2, &t1)
for i = 1; i < 5; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t2, &t1)
feSquare(&t2, &t1)
for i = 1; i < 10; i++ {
feSquare(&t2, &t2)
}
feMul(&t2, &t2, &t1)
feSquare(&t3, &t2)
for i = 1; i < 20; i++ {
feSquare(&t3, &t3)
}
feMul(&t2, &t3, &t2)
feSquare(&t2, &t2)
for i = 1; i < 10; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t2, &t1)
feSquare(&t2, &t1)
for i = 1; i < 50; i++ {
feSquare(&t2, &t2)
}
feMul(&t2, &t2, &t1)
feSquare(&t3, &t2)
for i = 1; i < 100; i++ {
feSquare(&t3, &t3)
}
feMul(&t2, &t3, &t2)
feSquare(&t2, &t2)
for i = 1; i < 50; i++ {
feSquare(&t2, &t2)
}
feMul(&t1, &t2, &t1)
feSquare(&t1, &t1)
for i = 1; i < 5; i++ {
feSquare(&t1, &t1)
}
feMul(out, &t1, &t0)
}
func scalarMultGeneric(out, in, base *[32]byte) {
var e [32]byte
copy(e[:], in[:])
e[0] &= 248
e[31] &= 127
e[31] |= 64
var x1, x2, z2, x3, z3, tmp0, tmp1 fieldElement
feFromBytes(&x1, base)
feOne(&x2)
feCopy(&x3, &x1)
feOne(&z3)
swap := int32(0)
for pos := 254; pos >= 0; pos-- {
b := e[pos/8] >> uint(pos&7)
b &= 1
swap ^= int32(b)
feCSwap(&x2, &x3, swap)
feCSwap(&z2, &z3, swap)
swap = int32(b)
feSub(&tmp0, &x3, &z3)
feSub(&tmp1, &x2, &z2)
feAdd(&x2, &x2, &z2)
feAdd(&z2, &x3, &z3)
feMul(&z3, &tmp0, &x2)
feMul(&z2, &z2, &tmp1)
feSquare(&tmp0, &tmp1)
feSquare(&tmp1, &x2)
feAdd(&x3, &z3, &z2)
feSub(&z2, &z3, &z2)
feMul(&x2, &tmp1, &tmp0)
feSub(&tmp1, &tmp1, &tmp0)
feSquare(&z2, &z2)
feMul121666(&z3, &tmp1)
feSquare(&x3, &x3)
feAdd(&tmp0, &tmp0, &z3)
feMul(&z3, &x1, &z2)
feMul(&z2, &tmp1, &tmp0)
}
feCSwap(&x2, &x3, swap)
feCSwap(&z2, &z3, swap)
feInvert(&z2, &z2)
feMul(&x2, &x2, &z2)
feToBytes(out, &x2)
}
// Copyright 2012 The Go Authors. All rights reserved.
// Copyright 2019 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.
// This code was translated into a form compatible with 6a from the public
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// +build !amd64 gccgo appengine purego
#define REDMASK51 0x0007FFFFFFFFFFFF
package curve25519
func scalarMult(out, in, base *[32]byte) {
scalarMultGeneric(out, in, base)
}
// 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.
// Package curve25519 provides an implementation of scalar multiplication on
// the elliptic curve known as curve25519. See https://cr.yp.to/ecdh.html
package curve25519 // import "golang.org/x/crypto/curve25519"
// basePoint is the x coordinate of the generator of the curve.
var basePoint = [32]byte{9, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0}
// ScalarMult sets dst to the product in*base where dst and base are the x
// coordinates of group points and all values are in little-endian form.
func ScalarMult(dst, in, base *[32]byte) {
scalarMult(dst, in, base)
}
// ScalarBaseMult sets dst to the product in*base where dst and base are the x
// coordinates of group points, base is the standard generator and all values
// are in little-endian form.
func ScalarBaseMult(dst, in *[32]byte) {
ScalarMult(dst, in, &basePoint)
}
// 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.
// This code was translated into a form compatible with 6a from the public
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// +build amd64,!gccgo,!appengine
#include "const_amd64.h"
// func freeze(inout *[5]uint64)
TEXT ·freeze(SB),7,$0-8
MOVQ inout+0(FP), DI
MOVQ 0(DI),SI
MOVQ 8(DI),DX
MOVQ 16(DI),CX
MOVQ 24(DI),R8
MOVQ 32(DI),R9
MOVQ $REDMASK51,AX
MOVQ AX,R10
SUBQ $18,R10
MOVQ $3,R11
REDUCELOOP:
MOVQ SI,R12
SHRQ $51,R12
ANDQ AX,SI
ADDQ R12,DX
MOVQ DX,R12
SHRQ $51,R12
ANDQ AX,DX
ADDQ R12,CX
MOVQ CX,R12
SHRQ $51,R12
ANDQ AX,CX
ADDQ R12,R8
MOVQ R8,R12
SHRQ $51,R12
ANDQ AX,R8
ADDQ R12,R9
MOVQ R9,R12
SHRQ $51,R12
ANDQ AX,R9
IMUL3Q $19,R12,R12
ADDQ R12,SI
SUBQ $1,R11
JA REDUCELOOP
MOVQ $1,R12
CMPQ R10,SI
CMOVQLT R11,R12
CMPQ AX,DX
CMOVQNE R11,R12
CMPQ AX,CX
CMOVQNE R11,R12
CMPQ AX,R8
CMOVQNE R11,R12
CMPQ AX,R9
CMOVQNE R11,R12
NEGQ R12
ANDQ R12,AX
ANDQ R12,R10
SUBQ R10,SI
SUBQ AX,DX
SUBQ AX,CX
SUBQ AX,R8
SUBQ AX,R9
MOVQ SI,0(DI)
MOVQ DX,8(DI)
MOVQ CX,16(DI)
MOVQ R8,24(DI)
MOVQ R9,32(DI)
RET
// 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.
// This code was translated into a form compatible with 6a from the public
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// +build amd64,!gccgo,!appengine
#include "const_amd64.h"
// func mul(dest, a, b *[5]uint64)
TEXT ·mul(SB),0,$16-24
MOVQ dest+0(FP), DI
MOVQ a+8(FP), SI
MOVQ b+16(FP), DX
MOVQ DX,CX
MOVQ 24(SI),DX
IMUL3Q $19,DX,AX
MOVQ AX,0(SP)
MULQ 16(CX)
MOVQ AX,R8
MOVQ DX,R9
MOVQ 32(SI),DX
IMUL3Q $19,DX,AX
MOVQ AX,8(SP)
MULQ 8(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 0(SI),AX
MULQ 0(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 0(SI),AX
MULQ 8(CX)
MOVQ AX,R10
MOVQ DX,R11
MOVQ 0(SI),AX
MULQ 16(CX)
MOVQ AX,R12
MOVQ DX,R13
MOVQ 0(SI),AX
MULQ 24(CX)
MOVQ AX,R14
MOVQ DX,R15
MOVQ 0(SI),AX
MULQ 32(CX)
MOVQ AX,BX
MOVQ DX,BP
MOVQ 8(SI),AX
MULQ 0(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 8(SI),AX
MULQ 8(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 8(SI),AX
MULQ 16(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ 8(SI),AX
MULQ 24(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 8(SI),DX
IMUL3Q $19,DX,AX
MULQ 32(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 16(SI),AX
MULQ 0(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 16(SI),AX
MULQ 8(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ 16(SI),AX
MULQ 16(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 16(SI),DX
IMUL3Q $19,DX,AX
MULQ 24(CX)
ADDQ AX,R8
ADCQ DX,R9
MOVQ 16(SI),DX
IMUL3Q $19,DX,AX
MULQ 32(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 24(SI),AX
MULQ 0(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ 24(SI),AX
MULQ 8(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 0(SP),AX
MULQ 24(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 0(SP),AX
MULQ 32(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 32(SI),AX
MULQ 0(CX)
ADDQ AX,BX
ADCQ DX,BP
MOVQ 8(SP),AX
MULQ 16(CX)
ADDQ AX,R10
ADCQ DX,R11
MOVQ 8(SP),AX
MULQ 24(CX)
ADDQ AX,R12
ADCQ DX,R13
MOVQ 8(SP),AX
MULQ 32(CX)
ADDQ AX,R14
ADCQ DX,R15
MOVQ $REDMASK51,SI
SHLQ $13,R8,R9
ANDQ SI,R8
SHLQ $13,R10,R11
ANDQ SI,R10
ADDQ R9,R10
SHLQ $13,R12,R13
ANDQ SI,R12
ADDQ R11,R12
SHLQ $13,R14,R15
ANDQ SI,R14
ADDQ R13,R14
SHLQ $13,BX,BP
ANDQ SI,BX
ADDQ R15,BX
IMUL3Q $19,BP,DX
ADDQ DX,R8
MOVQ R8,DX
SHRQ $51,DX
ADDQ R10,DX
MOVQ DX,CX
SHRQ $51,DX
ANDQ SI,R8
ADDQ R12,DX
MOVQ DX,R9
SHRQ $51,DX
ANDQ SI,CX
ADDQ R14,DX
MOVQ DX,AX
SHRQ $51,DX
ANDQ SI,R9
ADDQ BX,DX
MOVQ DX,R10
SHRQ $51,DX
ANDQ SI,AX
IMUL3Q $19,DX,DX
ADDQ DX,R8
ANDQ SI,R10
MOVQ R8,0(DI)
MOVQ CX,8(DI)
MOVQ R9,16(DI)
MOVQ AX,24(DI)
MOVQ R10,32(DI)
RET
// 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.
// This code was translated into a form compatible with 6a from the public
// domain sources in SUPERCOP: https://bench.cr.yp.to/supercop.html
// +build amd64,!gccgo,!appengine
#include "const_amd64.h"
// func square(out, in *[5]uint64)
TEXT ·square(SB),7,$0-16
MOVQ out+0(FP), DI
MOVQ in+8(FP), SI
MOVQ 0(SI),AX
MULQ 0(SI)
MOVQ AX,CX
MOVQ DX,R8
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 8(SI)
MOVQ AX,R9
MOVQ DX,R10
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 16(SI)
MOVQ AX,R11
MOVQ DX,R12
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 24(SI)
MOVQ AX,R13
MOVQ DX,R14
MOVQ 0(SI),AX
SHLQ $1,AX
MULQ 32(SI)
MOVQ AX,R15
MOVQ DX,BX
MOVQ 8(SI),AX
MULQ 8(SI)
ADDQ AX,R11
ADCQ DX,R12
MOVQ 8(SI),AX
SHLQ $1,AX
MULQ 16(SI)
ADDQ AX,R13
ADCQ DX,R14
MOVQ 8(SI),AX
SHLQ $1,AX
MULQ 24(SI)
ADDQ AX,R15
ADCQ DX,BX
MOVQ 8(SI),DX
IMUL3Q $38,DX,AX
MULQ 32(SI)
ADDQ AX,CX
ADCQ DX,R8
MOVQ 16(SI),AX
MULQ 16(SI)
ADDQ AX,R15
ADCQ DX,BX
MOVQ 16(SI),DX
IMUL3Q $38,DX,AX
MULQ 24(SI)
ADDQ AX,CX
ADCQ DX,R8
MOVQ 16(SI),DX
IMUL3Q $38,DX,AX
MULQ 32(SI)
ADDQ AX,R9
ADCQ DX,R10
MOVQ 24(SI),DX
IMUL3Q $19,DX,AX
MULQ 24(SI)
ADDQ AX,R9
ADCQ DX,R10
MOVQ 24(SI),DX
IMUL3Q $38,DX,AX
MULQ 32(SI)
ADDQ AX,R11
ADCQ DX,R12
MOVQ 32(SI),DX
IMUL3Q $19,DX,AX
MULQ 32(SI)
ADDQ AX,R13
ADCQ DX,R14
MOVQ $REDMASK51,SI
SHLQ $13,CX,R8
ANDQ SI,CX
SHLQ $13,R9,R10
ANDQ SI,R9
ADDQ R8,R9
SHLQ $13,R11,R12
ANDQ SI,R11
ADDQ R10,R11
SHLQ $13,R13,R14
ANDQ SI,R13
ADDQ R12,R13
SHLQ $13,R15,BX
ANDQ SI,R15
ADDQ R14,R15
IMUL3Q $19,BX,DX
ADDQ DX,CX
MOVQ CX,DX
SHRQ $51,DX
ADDQ R9,DX
ANDQ SI,CX
MOVQ DX,R8
SHRQ $51,DX
ADDQ R11,DX
ANDQ SI,R8
MOVQ DX,R9
SHRQ $51,DX
ADDQ R13,DX
ANDQ SI,R9
MOVQ DX,AX
SHRQ $51,DX
ADDQ R15,DX
ANDQ SI,AX
MOVQ DX,R10
SHRQ $51,DX
IMUL3Q $19,DX,DX
ADDQ DX,CX
ANDQ SI,R10
MOVQ CX,0(DI)
MOVQ R8,8(DI)
MOVQ R9,16(DI)
MOVQ AX,24(DI)
MOVQ R10,32(DI)
RET
// Copyright 2019 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.
// Based on CRYPTOGAMS code with the following comment:
// # ====================================================================
// # Written by Andy Polyakov <appro@openssl.org> for the OpenSSL
// # project. The module is, however, dual licensed under OpenSSL and
// # CRYPTOGAMS licenses depending on where you obtain it. For further
// # details see http://www.openssl.org/~appro/cryptogams/.
// # ====================================================================
// Original code can be found at the link below:
// https://github.com/dot-asm/cryptogams/commit/a60f5b50ed908e91e5c39ca79126a4a876d5d8ff
// There are some differences between CRYPTOGAMS code and this one. The round
// loop for "_int" isn't the same as the original. Some adjustments were
// necessary because there are less vector registers available. For example, some
// X variables (r12, r13, r14, and r15) share the same register used by the
// counter. The original code uses ctr to name the counter. Here we use CNT
// because golang uses CTR as the counter register name.
// +build ppc64le,!gccgo,!appengine
#include "textflag.h"
#define OUT R3
#define INP R4
#define LEN R5
#define KEY R6
#define CNT R7
#define TEMP R8
#define X0 R11
#define X1 R12
#define X2 R14
#define X3 R15
#define X4 R16
#define X5 R17
#define X6 R18
#define X7 R19
#define X8 R20
#define X9 R21
#define X10 R22
#define X11 R23
#define X12 R24
#define X13 R25
#define X14 R26
#define X15 R27
#define CON0 X0
#define CON1 X1
#define CON2 X2
#define CON3 X3
#define KEY0 X4
#define KEY1 X5
#define KEY2 X6
#define KEY3 X7
#define KEY4 X8
#define KEY5 X9
#define KEY6 X10
#define KEY7 X11
#define CNT0 X12
#define CNT1 X13
#define CNT2 X14
#define CNT3 X15
#define TMP0 R9
#define TMP1 R10
#define TMP2 R28
#define TMP3 R29
#define CONSTS R8
#define A0 V0
#define B0 V1
#define C0 V2
#define D0 V3
#define A1 V4
#define B1 V5
#define C1 V6
#define D1 V7
#define A2 V8
#define B2 V9
#define C2 V10
#define D2 V11
#define T0 V12
#define T1 V13
#define T2 V14
#define K0 V15
#define K1 V16
#define K2 V17
#define K3 V18
#define K4 V19
#define K5 V20
#define FOUR V21
#define SIXTEEN V22
#define TWENTY4 V23
#define TWENTY V24
#define TWELVE V25
#define TWENTY5 V26
#define SEVEN V27
#define INPPERM V28
#define OUTPERM V29
#define OUTMASK V30
#define DD0 V31
#define DD1 SEVEN
#define DD2 T0
#define DD3 T1
#define DD4 T2
DATA ·consts+0x00(SB)/8, $0x3320646e61707865
DATA ·consts+0x08(SB)/8, $0x6b20657479622d32
DATA ·consts+0x10(SB)/8, $0x0000000000000001
DATA ·consts+0x18(SB)/8, $0x0000000000000000
DATA ·consts+0x20(SB)/8, $0x0000000000000004
DATA ·consts+0x28(SB)/8, $0x0000000000000000
DATA ·consts+0x30(SB)/8, $0x0a0b08090e0f0c0d
DATA ·consts+0x38(SB)/8, $0x0203000106070405
DATA ·consts+0x40(SB)/8, $0x090a0b080d0e0f0c
DATA ·consts+0x48(SB)/8, $0x0102030005060704
GLOBL ·consts(SB), RODATA, $80
//func chaCha20_ctr32_vmx(out, inp *byte, len int, key *[32]byte, counter *[16]byte)
TEXT ·chaCha20_ctr32_vmx(SB),NOSPLIT|NOFRAME,$0
// Load the arguments inside the registers
MOVD out+0(FP), OUT
MOVD inp+8(FP), INP
MOVD len+16(FP), LEN
MOVD key+24(FP), KEY
MOVD counter+32(FP), CNT
MOVD consts(SB), CONSTS // point to consts addr
MOVD $16, X0
MOVD $32, X1
MOVD $48, X2
MOVD $64, X3
MOVD $31, X4
MOVD $15, X5
// Load key
LVX (KEY)(R0), K1
LVSR (KEY)(R0), T0
LVX (KEY)(X0), K2
LVX (KEY)(X4), DD0
// Load counter
LVX (CNT)(R0), K3
LVSR (CNT)(R0), T1
LVX (CNT)(X5), DD1
// Load constants
LVX (CONSTS)(R0), K0
LVX (CONSTS)(X0), K5
LVX (CONSTS)(X1), FOUR
LVX (CONSTS)(X2), SIXTEEN
LVX (CONSTS)(X3), TWENTY4
// Align key and counter
VPERM K2, K1, T0, K1
VPERM DD0, K2, T0, K2
VPERM DD1, K3, T1, K3
// Load counter to GPR
MOVWZ 0(CNT), CNT0
MOVWZ 4(CNT), CNT1
MOVWZ 8(CNT), CNT2
MOVWZ 12(CNT), CNT3
// Adjust vectors for the initial state
VADDUWM K3, K5, K3
VADDUWM K3, K5, K4
VADDUWM K4, K5, K5
// Synthesized constants
VSPLTISW $-12, TWENTY
VSPLTISW $12, TWELVE
VSPLTISW $-7, TWENTY5
VXOR T0, T0, T0
VSPLTISW $-1, OUTMASK
LVSR (INP)(R0), INPPERM
LVSL (OUT)(R0), OUTPERM
VPERM OUTMASK, T0, OUTPERM, OUTMASK
loop_outer_vmx:
// Load constant
MOVD $0x61707865, CON0
MOVD $0x3320646e, CON1
MOVD $0x79622d32, CON2
MOVD $0x6b206574, CON3
VOR K0, K0, A0
VOR K0, K0, A1
VOR K0, K0, A2
VOR K1, K1, B0
MOVD $10, TEMP
// Load key to GPR
MOVWZ 0(KEY), X4
MOVWZ 4(KEY), X5
MOVWZ 8(KEY), X6
MOVWZ 12(KEY), X7
VOR K1, K1, B1
VOR K1, K1, B2
MOVWZ 16(KEY), X8
MOVWZ 0(CNT), X12
MOVWZ 20(KEY), X9
MOVWZ 4(CNT), X13
VOR K2, K2, C0
VOR K2, K2, C1
MOVWZ 24(KEY), X10
MOVWZ 8(CNT), X14
VOR K2, K2, C2
VOR K3, K3, D0
MOVWZ 28(KEY), X11
MOVWZ 12(CNT), X15
VOR K4, K4, D1
VOR K5, K5, D2
MOVD X4, TMP0
MOVD X5, TMP1
MOVD X6, TMP2
MOVD X7, TMP3
VSPLTISW $7, SEVEN
MOVD TEMP, CTR
loop_vmx:
// CRYPTOGAMS uses a macro to create a loop using perl. This isn't possible
// using assembly macros. Therefore, the macro expansion result was used
// in order to maintain the algorithm efficiency.
// This loop generates three keystream blocks using VMX instructions and,
// in parallel, one keystream block using scalar instructions.
ADD X4, X0, X0
ADD X5, X1, X1
VADDUWM A0, B0, A0
VADDUWM A1, B1, A1
ADD X6, X2, X2
ADD X7, X3, X3
VADDUWM A2, B2, A2
VXOR D0, A0, D0
XOR X0, X12, X12
XOR X1, X13, X13
VXOR D1, A1, D1
VXOR D2, A2, D2
XOR X2, X14, X14
XOR X3, X15, X15
VPERM D0, D0, SIXTEEN, D0
VPERM D1, D1, SIXTEEN, D1
ROTLW $16, X12, X12
ROTLW $16, X13, X13
VPERM D2, D2, SIXTEEN, D2
VADDUWM C0, D0, C0
ROTLW $16, X14, X14
ROTLW $16, X15, X15
VADDUWM C1, D1, C1
VADDUWM C2, D2, C2
ADD X12, X8, X8
ADD X13, X9, X9
VXOR B0, C0, T0
VXOR B1, C1, T1
ADD X14, X10, X10
ADD X15, X11, X11
VXOR B2, C2, T2
VRLW T0, TWELVE, B0
XOR X8, X4, X4
XOR X9, X5, X5
VRLW T1, TWELVE, B1
VRLW T2, TWELVE, B2
XOR X10, X6, X6
XOR X11, X7, X7
VADDUWM A0, B0, A0
VADDUWM A1, B1, A1
ROTLW $12, X4, X4
ROTLW $12, X5, X5
VADDUWM A2, B2, A2
VXOR D0, A0, D0
ROTLW $12, X6, X6
ROTLW $12, X7, X7
VXOR D1, A1, D1
VXOR D2, A2, D2
ADD X4, X0, X0
ADD X5, X1, X1
VPERM D0, D0, TWENTY4, D0
VPERM D1, D1, TWENTY4, D1
ADD X6, X2, X2
ADD X7, X3, X3
VPERM D2, D2, TWENTY4, D2
VADDUWM C0, D0, C0
XOR X0, X12, X12
XOR X1, X13, X13
VADDUWM C1, D1, C1
VADDUWM C2, D2, C2
XOR X2, X14, X14
XOR X3, X15, X15
VXOR B0, C0, T0
VXOR B1, C1, T1
ROTLW $8, X12, X12
ROTLW $8, X13, X13
VXOR B2, C2, T2
VRLW T0, SEVEN, B0
ROTLW $8, X14, X14
ROTLW $8, X15, X15
VRLW T1, SEVEN, B1
VRLW T2, SEVEN, B2
ADD X12, X8, X8
ADD X13, X9, X9
VSLDOI $8, C0, C0, C0
VSLDOI $8, C1, C1, C1
ADD X14, X10, X10
ADD X15, X11, X11
VSLDOI $8, C2, C2, C2
VSLDOI $12, B0, B0, B0
XOR X8, X4, X4
XOR X9, X5, X5
VSLDOI $12, B1, B1, B1
VSLDOI $12, B2, B2, B2
XOR X10, X6, X6
XOR X11, X7, X7
VSLDOI $4, D0, D0, D0
VSLDOI $4, D1, D1, D1
ROTLW $7, X4, X4
ROTLW $7, X5, X5
VSLDOI $4, D2, D2, D2
VADDUWM A0, B0, A0
ROTLW $7, X6, X6
ROTLW $7, X7, X7
VADDUWM A1, B1, A1
VADDUWM A2, B2, A2
ADD X5, X0, X0
ADD X6, X1, X1
VXOR D0, A0, D0
VXOR D1, A1, D1
ADD X7, X2, X2
ADD X4, X3, X3
VXOR D2, A2, D2
VPERM D0, D0, SIXTEEN, D0
XOR X0, X15, X15
XOR X1, X12, X12
VPERM D1, D1, SIXTEEN, D1
VPERM D2, D2, SIXTEEN, D2
XOR X2, X13, X13
XOR X3, X14, X14
VADDUWM C0, D0, C0
VADDUWM C1, D1, C1
ROTLW $16, X15, X15
ROTLW $16, X12, X12
VADDUWM C2, D2, C2
VXOR B0, C0, T0
ROTLW $16, X13, X13
ROTLW $16, X14, X14
VXOR B1, C1, T1
VXOR B2, C2, T2
ADD X15, X10, X10
ADD X12, X11, X11
VRLW T0, TWELVE, B0
VRLW T1, TWELVE, B1
ADD X13, X8, X8
ADD X14, X9, X9
VRLW T2, TWELVE, B2
VADDUWM A0, B0, A0
XOR X10, X5, X5
XOR X11, X6, X6
VADDUWM A1, B1, A1
VADDUWM A2, B2, A2
XOR X8, X7, X7
XOR X9, X4, X4
VXOR D0, A0, D0
VXOR D1, A1, D1
ROTLW $12, X5, X5
ROTLW $12, X6, X6
VXOR D2, A2, D2
VPERM D0, D0, TWENTY4, D0
ROTLW $12, X7, X7
ROTLW $12, X4, X4
VPERM D1, D1, TWENTY4, D1
VPERM D2, D2, TWENTY4, D2
ADD X5, X0, X0
ADD X6, X1, X1
VADDUWM C0, D0, C0
VADDUWM C1, D1, C1
ADD X7, X2, X2
ADD X4, X3, X3
VADDUWM C2, D2, C2
VXOR B0, C0, T0
XOR X0, X15, X15
XOR X1, X12, X12
VXOR B1, C1, T1
VXOR B2, C2, T2
XOR X2, X13, X13
XOR X3, X14, X14
VRLW T0, SEVEN, B0
VRLW T1, SEVEN, B1
ROTLW $8, X15, X15
ROTLW $8, X12, X12
VRLW T2, SEVEN, B2
VSLDOI $8, C0, C0, C0
ROTLW $8, X13, X13
ROTLW $8, X14, X14
VSLDOI $8, C1, C1, C1
VSLDOI $8, C2, C2, C2
ADD X15, X10, X10
ADD X12, X11, X11
VSLDOI $4, B0, B0, B0
VSLDOI $4, B1, B1, B1
ADD X13, X8, X8
ADD X14, X9, X9
VSLDOI $4, B2, B2, B2
VSLDOI $12, D0, D0, D0
XOR X10, X5, X5
XOR X11, X6, X6
VSLDOI $12, D1, D1, D1
VSLDOI $12, D2, D2, D2
XOR X8, X7, X7
XOR X9, X4, X4
ROTLW $7, X5, X5
ROTLW $7, X6, X6
ROTLW $7, X7, X7
ROTLW $7, X4, X4
BC 0x10, 0, loop_vmx
SUB $256, LEN, LEN
// Accumulate key block
ADD $0x61707865, X0, X0
ADD $0x3320646e, X1, X1
ADD $0x79622d32, X2, X2
ADD $0x6b206574, X3, X3
ADD TMP0, X4, X4
ADD TMP1, X5, X5
ADD TMP2, X6, X6
ADD TMP3, X7, X7
MOVWZ 16(KEY), TMP0
MOVWZ 20(KEY), TMP1
MOVWZ 24(KEY), TMP2
MOVWZ 28(KEY), TMP3
ADD TMP0, X8, X8
ADD TMP1, X9, X9
ADD TMP2, X10, X10
ADD TMP3, X11, X11
MOVWZ 12(CNT), TMP0
MOVWZ 8(CNT), TMP1
MOVWZ 4(CNT), TMP2
MOVWZ 0(CNT), TEMP
ADD TMP0, X15, X15
ADD TMP1, X14, X14
ADD TMP2, X13, X13
ADD TEMP, X12, X12
// Accumulate key block
VADDUWM A0, K0, A0
VADDUWM A1, K0, A1
VADDUWM A2, K0, A2
VADDUWM B0, K1, B0
VADDUWM B1, K1, B1
VADDUWM B2, K1, B2
VADDUWM C0, K2, C0
VADDUWM C1, K2, C1
VADDUWM C2, K2, C2
VADDUWM D0, K3, D0
VADDUWM D1, K4, D1
VADDUWM D2, K5, D2
// Increment counter
ADD $4, TEMP, TEMP
MOVW TEMP, 0(CNT)
VADDUWM K3, FOUR, K3
VADDUWM K4, FOUR, K4
VADDUWM K5, FOUR, K5
// XOR the input slice (INP) with the keystream, which is stored in GPRs (X0-X3).
// Load input (aligned or not)
MOVWZ 0(INP), TMP0
MOVWZ 4(INP), TMP1
MOVWZ 8(INP), TMP2
MOVWZ 12(INP), TMP3
// XOR with input
XOR TMP0, X0, X0
XOR TMP1, X1, X1
XOR TMP2, X2, X2
XOR TMP3, X3, X3
MOVWZ 16(INP), TMP0
MOVWZ 20(INP), TMP1
MOVWZ 24(INP), TMP2
MOVWZ 28(INP), TMP3
XOR TMP0, X4, X4
XOR TMP1, X5, X5
XOR TMP2, X6, X6
XOR TMP3, X7, X7
MOVWZ 32(INP), TMP0
MOVWZ 36(INP), TMP1
MOVWZ 40(INP), TMP2
MOVWZ 44(INP), TMP3
XOR TMP0, X8, X8
XOR TMP1, X9, X9
XOR TMP2, X10, X10
XOR TMP3, X11, X11
MOVWZ 48(INP), TMP0
MOVWZ 52(INP), TMP1
MOVWZ 56(INP), TMP2
MOVWZ 60(INP), TMP3
XOR TMP0, X12, X12
XOR TMP1, X13, X13
XOR TMP2, X14, X14
XOR TMP3, X15, X15
// Store output (aligned or not)
MOVW X0, 0(OUT)
MOVW X1, 4(OUT)
MOVW X2, 8(OUT)
MOVW X3, 12(OUT)
ADD $64, INP, INP // INP points to the end of the slice for the alignment code below
MOVW X4, 16(OUT)
MOVD $16, TMP0
MOVW X5, 20(OUT)
MOVD $32, TMP1
MOVW X6, 24(OUT)
MOVD $48, TMP2
MOVW X7, 28(OUT)
MOVD $64, TMP3
MOVW X8, 32(OUT)
MOVW X9, 36(OUT)
MOVW X10, 40(OUT)
MOVW X11, 44(OUT)
MOVW X12, 48(OUT)
MOVW X13, 52(OUT)
MOVW X14, 56(OUT)
MOVW X15, 60(OUT)
ADD $64, OUT, OUT
// Load input
LVX (INP)(R0), DD0
LVX (INP)(TMP0), DD1
LVX (INP)(TMP1), DD2
LVX (INP)(TMP2), DD3
LVX (INP)(TMP3), DD4
ADD $64, INP, INP
VPERM DD1, DD0, INPPERM, DD0 // Align input
VPERM DD2, DD1, INPPERM, DD1
VPERM DD3, DD2, INPPERM, DD2
VPERM DD4, DD3, INPPERM, DD3
VXOR A0, DD0, A0 // XOR with input
VXOR B0, DD1, B0
LVX (INP)(TMP0), DD1 // Keep loading input
VXOR C0, DD2, C0
LVX (INP)(TMP1), DD2
VXOR D0, DD3, D0
LVX (INP)(TMP2), DD3
LVX (INP)(TMP3), DD0
ADD $64, INP, INP
MOVD $63, TMP3 // 63 is not a typo
VPERM A0, A0, OUTPERM, A0
VPERM B0, B0, OUTPERM, B0
VPERM C0, C0, OUTPERM, C0
VPERM D0, D0, OUTPERM, D0
VPERM DD1, DD4, INPPERM, DD4 // Align input
VPERM DD2, DD1, INPPERM, DD1
VPERM DD3, DD2, INPPERM, DD2
VPERM DD0, DD3, INPPERM, DD3
VXOR A1, DD4, A1
VXOR B1, DD1, B1
LVX (INP)(TMP0), DD1 // Keep loading
VXOR C1, DD2, C1
LVX (INP)(TMP1), DD2
VXOR D1, DD3, D1
LVX (INP)(TMP2), DD3
// Note that the LVX address is always rounded down to the nearest 16-byte
// boundary, and that it always points to at most 15 bytes beyond the end of
// the slice, so we cannot cross a page boundary.
LVX (INP)(TMP3), DD4 // Redundant in aligned case.
ADD $64, INP, INP
VPERM A1, A1, OUTPERM, A1 // Pre-misalign output
VPERM B1, B1, OUTPERM, B1
VPERM C1, C1, OUTPERM, C1
VPERM D1, D1, OUTPERM, D1
VPERM DD1, DD0, INPPERM, DD0 // Align Input
VPERM DD2, DD1, INPPERM, DD1
VPERM DD3, DD2, INPPERM, DD2
VPERM DD4, DD3, INPPERM, DD3
VXOR A2, DD0, A2
VXOR B2, DD1, B2
VXOR C2, DD2, C2
VXOR D2, DD3, D2
VPERM A2, A2, OUTPERM, A2
VPERM B2, B2, OUTPERM, B2
VPERM C2, C2, OUTPERM, C2
VPERM D2, D2, OUTPERM, D2
ANDCC $15, OUT, X1 // Is out aligned?
MOVD OUT, X0
VSEL A0, B0, OUTMASK, DD0 // Collect pre-misaligned output
VSEL B0, C0, OUTMASK, DD1
VSEL C0, D0, OUTMASK, DD2
VSEL D0, A1, OUTMASK, DD3
VSEL A1, B1, OUTMASK, B0
VSEL B1, C1, OUTMASK, C0
VSEL C1, D1, OUTMASK, D0
VSEL D1, A2, OUTMASK, A1
VSEL A2, B2, OUTMASK, B1
VSEL B2, C2, OUTMASK, C1
VSEL C2, D2, OUTMASK, D1
STVX DD0, (OUT+TMP0)
STVX DD1, (OUT+TMP1)
STVX DD2, (OUT+TMP2)
ADD $64, OUT, OUT
STVX DD3, (OUT+R0)
STVX B0, (OUT+TMP0)
STVX C0, (OUT+TMP1)
STVX D0, (OUT+TMP2)
ADD $64, OUT, OUT
STVX A1, (OUT+R0)
STVX B1, (OUT+TMP0)
STVX C1, (OUT+TMP1)
STVX D1, (OUT+TMP2)
ADD $64, OUT, OUT
BEQ aligned_vmx
SUB X1, OUT, X2 // in misaligned case edges
MOVD $0, X3 // are written byte-by-byte
unaligned_tail_vmx:
STVEBX D2, (X2+X3)
ADD $1, X3, X3
CMPW X3, X1
BNE unaligned_tail_vmx
SUB X1, X0, X2
unaligned_head_vmx:
STVEBX A0, (X2+X1)
CMPW X1, $15
ADD $1, X1, X1
BNE unaligned_head_vmx
CMPU LEN, $255 // done with 256-byte block yet?
BGT loop_outer_vmx
JMP done_vmx
aligned_vmx:
STVX A0, (X0+R0)
CMPU LEN, $255 // done with 256-byte block yet?
BGT loop_outer_vmx
done_vmx:
RET
// 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.
// Package ChaCha20 implements the core ChaCha20 function as specified
// in https://tools.ietf.org/html/rfc7539#section-2.3.
package chacha20
import (
"crypto/cipher"
"encoding/binary"
"golang.org/x/crypto/internal/subtle"
)
// assert that *Cipher implements cipher.Stream
var _ cipher.Stream = (*Cipher)(nil)
// Cipher is a stateful instance of ChaCha20 using a particular key
// and nonce. A *Cipher implements the cipher.Stream interface.
type Cipher struct {
key [8]uint32
counter uint32 // incremented after each block
nonce [3]uint32
buf [bufSize]byte // buffer for unused keystream bytes
len int // number of unused keystream bytes at end of buf
}
// New creates a new ChaCha20 stream cipher with the given key and nonce.
// The initial counter value is set to 0.
func New(key [8]uint32, nonce [3]uint32) *Cipher {
return &Cipher{key: key, nonce: nonce}
}
// ChaCha20 constants spelling "expand 32-byte k"
const (
j0 uint32 = 0x61707865
j1 uint32 = 0x3320646e
j2 uint32 = 0x79622d32
j3 uint32 = 0x6b206574
)
func quarterRound(a, b, c, d uint32) (uint32, uint32, uint32, uint32) {
a += b
d ^= a
d = (d << 16) | (d >> 16)
c += d
b ^= c
b = (b << 12) | (b >> 20)
a += b
d ^= a
d = (d << 8) | (d >> 24)
c += d
b ^= c
b = (b << 7) | (b >> 25)
return a, b, c, d
}
// XORKeyStream XORs each byte in the given slice with a byte from the
// cipher's key stream. Dst and src must overlap entirely or not at all.
//
// If len(dst) < len(src), XORKeyStream will panic. It is acceptable
// to pass a dst bigger than src, and in that case, XORKeyStream will
// only update dst[:len(src)] and will not touch the rest of dst.
//
// Multiple calls to XORKeyStream behave as if the concatenation of
// the src buffers was passed in a single run. That is, Cipher
// maintains state and does not reset at each XORKeyStream call.
func (s *Cipher) XORKeyStream(dst, src []byte) {
if len(dst) < len(src) {
panic("chacha20: output smaller than input")
}
if subtle.InexactOverlap(dst[:len(src)], src) {
panic("chacha20: invalid buffer overlap")
}
// xor src with buffered keystream first
if s.len != 0 {
buf := s.buf[len(s.buf)-s.len:]
if len(src) < len(buf) {
buf = buf[:len(src)]
}
td, ts := dst[:len(buf)], src[:len(buf)] // BCE hint
for i, b := range buf {
td[i] = ts[i] ^ b
}
s.len -= len(buf)
if s.len != 0 {
return
}
s.buf = [len(s.buf)]byte{} // zero the empty buffer
src = src[len(buf):]
dst = dst[len(buf):]
}
if len(src) == 0 {
return
}
if haveAsm {
if uint64(len(src))+uint64(s.counter)*64 > (1<<38)-64 {
panic("chacha20: counter overflow")
}
s.xorKeyStreamAsm(dst, src)
return
}
// set up a 64-byte buffer to pad out the final block if needed
// (hoisted out of the main loop to avoid spills)
rem := len(src) % 64 // length of final block
fin := len(src) - rem // index of final block
if rem > 0 {
copy(s.buf[len(s.buf)-64:], src[fin:])
}
// pre-calculate most of the first round
s1, s5, s9, s13 := quarterRound(j1, s.key[1], s.key[5], s.nonce[0])
s2, s6, s10, s14 := quarterRound(j2, s.key[2], s.key[6], s.nonce[1])
s3, s7, s11, s15 := quarterRound(j3, s.key[3], s.key[7], s.nonce[2])
n := len(src)
src, dst = src[:n:n], dst[:n:n] // BCE hint
for i := 0; i < n; i += 64 {
// calculate the remainder of the first round
s0, s4, s8, s12 := quarterRound(j0, s.key[0], s.key[4], s.counter)
// execute the second round
x0, x5, x10, x15 := quarterRound(s0, s5, s10, s15)
x1, x6, x11, x12 := quarterRound(s1, s6, s11, s12)
x2, x7, x8, x13 := quarterRound(s2, s7, s8, s13)
x3, x4, x9, x14 := quarterRound(s3, s4, s9, s14)
// execute the remaining 18 rounds
for i := 0; i < 9; i++ {
x0, x4, x8, x12 = quarterRound(x0, x4, x8, x12)
x1, x5, x9, x13 = quarterRound(x1, x5, x9, x13)
x2, x6, x10, x14 = quarterRound(x2, x6, x10, x14)
x3, x7, x11, x15 = quarterRound(x3, x7, x11, x15)
x0, x5, x10, x15 = quarterRound(x0, x5, x10, x15)
x1, x6, x11, x12 = quarterRound(x1, x6, x11, x12)
x2, x7, x8, x13 = quarterRound(x2, x7, x8, x13)
x3, x4, x9, x14 = quarterRound(x3, x4, x9, x14)
}
x0 += j0
x1 += j1
x2 += j2
x3 += j3
x4 += s.key[0]
x5 += s.key[1]
x6 += s.key[2]
x7 += s.key[3]
x8 += s.key[4]
x9 += s.key[5]
x10 += s.key[6]
x11 += s.key[7]
x12 += s.counter
x13 += s.nonce[0]
x14 += s.nonce[1]
x15 += s.nonce[2]
// increment the counter
s.counter += 1
if s.counter == 0 {
panic("chacha20: counter overflow")
}
// pad to 64 bytes if needed
in, out := src[i:], dst[i:]
if i == fin {
// src[fin:] has already been copied into s.buf before
// the main loop
in, out = s.buf[len(s.buf)-64:], s.buf[len(s.buf)-64:]
}
in, out = in[:64], out[:64] // BCE hint
// XOR the key stream with the source and write out the result
xor(out[0:], in[0:], x0)
xor(out[4:], in[4:], x1)
xor(out[8:], in[8:], x2)
xor(out[12:], in[12:], x3)
xor(out[16:], in[16:], x4)
xor(out[20:], in[20:], x5)
xor(out[24:], in[24:], x6)
xor(out[28:], in[28:], x7)
xor(out[32:], in[32:], x8)
xor(out[36:], in[36:], x9)
xor(out[40:], in[40:], x10)
xor(out[44:], in[44:], x11)
xor(out[48:], in[48:], x12)
xor(out[52:], in[52:], x13)
xor(out[56:], in[56:], x14)
xor(out[60:], in[60:], x15)
}
// copy any trailing bytes out of the buffer and into dst
if rem != 0 {
s.len = 64 - rem
copy(dst[fin:], s.buf[len(s.buf)-64:])
}
}
// Advance discards bytes in the key stream until the next 64 byte block
// boundary is reached and updates the counter accordingly. If the key
// stream is already at a block boundary no bytes will be discarded and
// the counter will be unchanged.
func (s *Cipher) Advance() {
s.len -= s.len % 64
if s.len == 0 {
s.buf = [len(s.buf)]byte{}
}
}
// XORKeyStream crypts bytes from in to out using the given key and counters.
// In and out must overlap entirely or not at all. Counter contains the raw
// ChaCha20 counter bytes (i.e. block counter followed by nonce).
func XORKeyStream(out, in []byte, counter *[16]byte, key *[32]byte) {
s := Cipher{
key: [8]uint32{
binary.LittleEndian.Uint32(key[0:4]),
binary.LittleEndian.Uint32(key[4:8]),
binary.LittleEndian.Uint32(key[8:12]),
binary.LittleEndian.Uint32(key[12:16]),
binary.LittleEndian.Uint32(key[16:20]),
binary.LittleEndian.Uint32(key[20:24]),
binary.LittleEndian.Uint32(key[24:28]),
binary.LittleEndian.Uint32(key[28:32]),
},
nonce: [3]uint32{
binary.LittleEndian.Uint32(counter[4:8]),
binary.LittleEndian.Uint32(counter[8:12]),
binary.LittleEndian.Uint32(counter[12:16]),
},
counter: binary.LittleEndian.Uint32(counter[0:4]),
}
s.XORKeyStream(out, in)
}
// HChaCha20 uses the ChaCha20 core to generate a derived key from a key and a
// nonce. It should only be used as part of the XChaCha20 construction.
func HChaCha20(key *[8]uint32, nonce *[4]uint32) [8]uint32 {
x0, x1, x2, x3 := j0, j1, j2, j3
x4, x5, x6, x7 := key[0], key[1], key[2], key[3]
x8, x9, x10, x11 := key[4], key[5], key[6], key[7]
x12, x13, x14, x15 := nonce[0], nonce[1], nonce[2], nonce[3]
for i := 0; i < 10; i++ {
x0, x4, x8, x12 = quarterRound(x0, x4, x8, x12)
x1, x5, x9, x13 = quarterRound(x1, x5, x9, x13)
x2, x6, x10, x14 = quarterRound(x2, x6, x10, x14)
x3, x7, x11, x15 = quarterRound(x3, x7, x11, x15)
x0, x5, x10, x15 = quarterRound(x0, x5, x10, x15)
x1, x6, x11, x12 = quarterRound(x1, x6, x11, x12)
x2, x7, x8, x13 = quarterRound(x2, x7, x8, x13)
x3, x4, x9, x14 = quarterRound(x3, x4, x9, x14)
}
var out [8]uint32
out[0], out[1], out[2], out[3] = x0, x1, x2, x3
out[4], out[5], out[6], out[7] = x12, x13, x14, x15
return out
}
// Copyright 2019 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 ppc64le,!gccgo,!appengine
package chacha20
import "encoding/binary"
const (
bufSize = 256
haveAsm = true
)
//go:noescape
func chaCha20_ctr32_vmx(out, inp *byte, len int, key *[8]uint32, counter *uint32)
func (c *Cipher) xorKeyStreamAsm(dst, src []byte) {
if len(src) >= bufSize {
chaCha20_ctr32_vmx(&dst[0], &src[0], len(src)-len(src)%bufSize, &c.key, &c.counter)
}
if len(src)%bufSize != 0 {
chaCha20_ctr32_vmx(&c.buf[0], &c.buf[0], bufSize, &c.key, &c.counter)
start := len(src) - len(src)%bufSize
ts, td, tb := src[start:], dst[start:], c.buf[:]
// Unroll loop to XOR 32 bytes per iteration.
for i := 0; i < len(ts)-32; i += 32 {
td, tb = td[:len(ts)], tb[:len(ts)] // bounds check elimination
s0 := binary.LittleEndian.Uint64(ts[0:8])
s1 := binary.LittleEndian.Uint64(ts[8:16])
s2 := binary.LittleEndian.Uint64(ts[16:24])
s3 := binary.LittleEndian.Uint64(ts[24:32])
b0 := binary.LittleEndian.Uint64(tb[0:8])
b1 := binary.LittleEndian.Uint64(tb[8:16])
b2 := binary.LittleEndian.Uint64(tb[16:24])
b3 := binary.LittleEndian.Uint64(tb[24:32])
binary.LittleEndian.PutUint64(td[0:8], s0^b0)
binary.LittleEndian.PutUint64(td[8:16], s1^b1)
binary.LittleEndian.PutUint64(td[16:24], s2^b2)
binary.LittleEndian.PutUint64(td[24:32], s3^b3)
ts, td, tb = ts[32:], td[32:], tb[32:]
}
td, tb = td[:len(ts)], tb[:len(ts)] // bounds check elimination
for i, v := range ts {
td[i] = tb[i] ^ v
}
c.len = bufSize - (len(src) % bufSize)
}
}
// Copyright 2019 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 !go1.13
package poly1305
// Generic fallbacks for the math/bits intrinsics, copied from
// src/math/bits/bits.go. They were added in Go 1.12, but Add64 and Sum64 had
// variable time fallbacks until Go 1.13.
func bitsAdd64(x, y, carry uint64) (sum, carryOut uint64) {
sum = x + y + carry
carryOut = ((x & y) | ((x | y) &^ sum)) >> 63
return
}
func bitsSub64(x, y, borrow uint64) (diff, borrowOut uint64) {
diff = x - y - borrow
borrowOut = ((^x & y) | (^(x ^ y) & diff)) >> 63
return
}
func bitsMul64(x, y uint64) (hi, lo uint64) {
const mask32 = 1<<32 - 1
x0 := x & mask32
x1 := x >> 32
y0 := y & mask32
y1 := y >> 32
w0 := x0 * y0
t := x1*y0 + w0>>32
w1 := t & mask32
w2 := t >> 32
w1 += x0 * y1
hi = x1*y1 + w2 + w1>>32
lo = x * y
return
}
// Copyright 2019 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 go1.13
package poly1305
import "math/bits"
func bitsAdd64(x, y, carry uint64) (sum, carryOut uint64) {
return bits.Add64(x, y, carry)
}
func bitsSub64(x, y, borrow uint64) (diff, borrowOut uint64) {
return bits.Sub64(x, y, borrow)
}
func bitsMul64(x, y uint64) (hi, lo uint64) {
return bits.Mul64(x, y)
}
......@@ -22,8 +22,14 @@ import "crypto/subtle"
// TagSize is the size, in bytes, of a poly1305 authenticator.
const TagSize = 16
// Verify returns true if mac is a valid authenticator for m with the given
// key.
// Sum generates an authenticator for msg using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[16]byte, m []byte, key *[32]byte) {
sum(out, m, key)
}
// Verify returns true if mac is a valid authenticator for m with the given key.
func Verify(mac *[16]byte, m []byte, key *[32]byte) bool {
var tmp [16]byte
Sum(&tmp, m, key)
......
......@@ -7,62 +7,52 @@
package poly1305
//go:noescape
func initialize(state *[7]uint64, key *[32]byte)
func update(state *macState, msg []byte)
//go:noescape
func update(state *[7]uint64, msg []byte)
//go:noescape
func finalize(tag *[TagSize]byte, state *[7]uint64)
// Sum generates an authenticator for m using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[16]byte, m []byte, key *[32]byte) {
func sum(out *[16]byte, m []byte, key *[32]byte) {
h := newMAC(key)
h.Write(m)
h.Sum(out)
}
func newMAC(key *[32]byte) (h mac) {
initialize(&h.state, key)
initialize(key, &h.r, &h.s)
return
}
type mac struct {
state [7]uint64 // := uint64{ h0, h1, h2, r0, r1, pad0, pad1 }
// mac is a wrapper for macGeneric that redirects calls that would have gone to
// updateGeneric to update.
//
// Its Write and Sum methods are otherwise identical to the macGeneric ones, but
// using function pointers would carry a major performance cost.
type mac struct{ macGeneric }
buffer [TagSize]byte
offset int
}
func (h *mac) Write(p []byte) (n int, err error) {
n = len(p)
func (h *mac) Write(p []byte) (int, error) {
nn := len(p)
if h.offset > 0 {
remaining := TagSize - h.offset
if n < remaining {
h.offset += copy(h.buffer[h.offset:], p)
return n, nil
n := copy(h.buffer[h.offset:], p)
if h.offset+n < TagSize {
h.offset += n
return nn, nil
}
copy(h.buffer[h.offset:], p[:remaining])
p = p[remaining:]
p = p[n:]
h.offset = 0
update(&h.state, h.buffer[:])
update(&h.macState, h.buffer[:])
}
if nn := len(p) - (len(p) % TagSize); nn > 0 {
update(&h.state, p[:nn])
p = p[nn:]
if n := len(p) - (len(p) % TagSize); n > 0 {
update(&h.macState, p[:n])
p = p[n:]
}
if len(p) > 0 {
h.offset += copy(h.buffer[h.offset:], p)
}
return n, nil
return nn, nil
}
func (h *mac) Sum(out *[16]byte) {
state := h.state
state := h.macState
if h.offset > 0 {
update(&state, h.buffer[:h.offset])
}
finalize(out, &state)
finalize(out, &state.h, &state.s)
}
......@@ -54,10 +54,6 @@
ADCQ t3, h1; \
ADCQ $0, h2
DATA ·poly1305Mask<>+0x00(SB)/8, $0x0FFFFFFC0FFFFFFF
DATA ·poly1305Mask<>+0x08(SB)/8, $0x0FFFFFFC0FFFFFFC
GLOBL ·poly1305Mask<>(SB), RODATA, $16
// func update(state *[7]uint64, msg []byte)
TEXT ·update(SB), $0-32
MOVQ state+0(FP), DI
......@@ -110,39 +106,3 @@ done:
MOVQ R9, 8(DI)
MOVQ R10, 16(DI)
RET
// func initialize(state *[7]uint64, key *[32]byte)
TEXT ·initialize(SB), $0-16
MOVQ state+0(FP), DI
MOVQ key+8(FP), SI
// state[0...7] is initialized with zero
MOVOU 0(SI), X0
MOVOU 16(SI), X1
MOVOU ·poly1305Mask<>(SB), X2
PAND X2, X0
MOVOU X0, 24(DI)
MOVOU X1, 40(DI)
RET
// func finalize(tag *[TagSize]byte, state *[7]uint64)
TEXT ·finalize(SB), $0-16
MOVQ tag+0(FP), DI
MOVQ state+8(FP), SI
MOVQ 0(SI), AX
MOVQ 8(SI), BX
MOVQ 16(SI), CX
MOVQ AX, R8
MOVQ BX, R9
SUBQ $0xFFFFFFFFFFFFFFFB, AX
SBBQ $0xFFFFFFFFFFFFFFFF, BX
SBBQ $3, CX
CMOVQCS R8, AX
CMOVQCS R9, BX
ADDQ 40(SI), AX
ADCQ 48(SI), BX
MOVQ AX, 0(DI)
MOVQ BX, 8(DI)
RET
......@@ -6,14 +6,11 @@
package poly1305
// This function is implemented in sum_arm.s
// poly1305_auth_armv6 is implemented in sum_arm.s
//go:noescape
func poly1305_auth_armv6(out *[16]byte, m *byte, mlen uint32, key *[32]byte)
// Sum generates an authenticator for m using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[16]byte, m []byte, key *[32]byte) {
func sum(out *[16]byte, m []byte, key *[32]byte) {
var mPtr *byte
if len(m) > 0 {
mPtr = &m[0]
......
......@@ -2,18 +2,29 @@
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// This file provides the generic implementation of Sum and MAC. Other files
// might provide optimized assembly implementations of some of this code.
package poly1305
import "encoding/binary"
const (
msgBlock = uint32(1 << 24)
finalBlock = uint32(0)
)
// Poly1305 [RFC 7539] is a relatively simple algorithm: the authentication tag
// for a 64 bytes message is approximately
//
// s + m[0:16] * r⁴ + m[16:32] * r³ + m[32:48] * r² + m[48:64] * r mod 2¹³⁰ - 5
//
// for some secret r and s. It can be computed sequentially like
//
// for len(msg) > 0:
// h += read(msg, 16)
// h *= r
// h %= 2¹³⁰ - 5
// return h + s
//
// All the complexity is about doing performant constant-time math on numbers
// larger than any available numeric type.
// sumGeneric generates an authenticator for msg using a one-time key and
// puts the 16-byte result into out. This is the generic implementation of
// Sum and should be called if no assembly implementation is available.
func sumGeneric(out *[TagSize]byte, msg []byte, key *[32]byte) {
h := newMACGeneric(key)
h.Write(msg)
......@@ -21,152 +32,276 @@ func sumGeneric(out *[TagSize]byte, msg []byte, key *[32]byte) {
}
func newMACGeneric(key *[32]byte) (h macGeneric) {
h.r[0] = binary.LittleEndian.Uint32(key[0:]) & 0x3ffffff
h.r[1] = (binary.LittleEndian.Uint32(key[3:]) >> 2) & 0x3ffff03
h.r[2] = (binary.LittleEndian.Uint32(key[6:]) >> 4) & 0x3ffc0ff
h.r[3] = (binary.LittleEndian.Uint32(key[9:]) >> 6) & 0x3f03fff
h.r[4] = (binary.LittleEndian.Uint32(key[12:]) >> 8) & 0x00fffff
h.s[0] = binary.LittleEndian.Uint32(key[16:])
h.s[1] = binary.LittleEndian.Uint32(key[20:])
h.s[2] = binary.LittleEndian.Uint32(key[24:])
h.s[3] = binary.LittleEndian.Uint32(key[28:])
initialize(key, &h.r, &h.s)
return
}
// macState holds numbers in saturated 64-bit little-endian limbs. That is,
// the value of [x0, x1, x2] is x[0] + x[1] * 2⁶⁴ + x[2] * 2¹²⁸.
type macState struct {
// h is the main accumulator. It is to be interpreted modulo 2¹³⁰ - 5, but
// can grow larger during and after rounds.
h [3]uint64
// r and s are the private key components.
r [2]uint64
s [2]uint64
}
type macGeneric struct {
h, r [5]uint32
s [4]uint32
macState
buffer [TagSize]byte
offset int
}
func (h *macGeneric) Write(p []byte) (n int, err error) {
n = len(p)
// Write splits the incoming message into TagSize chunks, and passes them to
// update. It buffers incomplete chunks.
func (h *macGeneric) Write(p []byte) (int, error) {
nn := len(p)
if h.offset > 0 {
remaining := TagSize - h.offset
if n < remaining {
h.offset += copy(h.buffer[h.offset:], p)
return n, nil
n := copy(h.buffer[h.offset:], p)
if h.offset+n < TagSize {
h.offset += n
return nn, nil
}
copy(h.buffer[h.offset:], p[:remaining])
p = p[remaining:]
p = p[n:]
h.offset = 0
updateGeneric(h.buffer[:], msgBlock, &(h.h), &(h.r))
updateGeneric(&h.macState, h.buffer[:])
}
if nn := len(p) - (len(p) % TagSize); nn > 0 {
updateGeneric(p, msgBlock, &(h.h), &(h.r))
p = p[nn:]
if n := len(p) - (len(p) % TagSize); n > 0 {
updateGeneric(&h.macState, p[:n])
p = p[n:]
}
if len(p) > 0 {
h.offset += copy(h.buffer[h.offset:], p)
}
return n, nil
return nn, nil
}
func (h *macGeneric) Sum(out *[16]byte) {
H, R := h.h, h.r
// Sum flushes the last incomplete chunk from the buffer, if any, and generates
// the MAC output. It does not modify its state, in order to allow for multiple
// calls to Sum, even if no Write is allowed after Sum.
func (h *macGeneric) Sum(out *[TagSize]byte) {
state := h.macState
if h.offset > 0 {
var buffer [TagSize]byte
copy(buffer[:], h.buffer[:h.offset])
buffer[h.offset] = 1 // invariant: h.offset < TagSize
updateGeneric(buffer[:], finalBlock, &H, &R)
updateGeneric(&state, h.buffer[:h.offset])
}
finalize(out, &state.h, &state.s)
}
// [rMask0, rMask1] is the specified Poly1305 clamping mask in little-endian. It
// clears some bits of the secret coefficient to make it possible to implement
// multiplication more efficiently.
const (
rMask0 = 0x0FFFFFFC0FFFFFFF
rMask1 = 0x0FFFFFFC0FFFFFFC
)
func initialize(key *[32]byte, r, s *[2]uint64) {
r[0] = binary.LittleEndian.Uint64(key[0:8]) & rMask0
r[1] = binary.LittleEndian.Uint64(key[8:16]) & rMask1
s[0] = binary.LittleEndian.Uint64(key[16:24])
s[1] = binary.LittleEndian.Uint64(key[24:32])
}
// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
// bits.Mul64 and bits.Add64 intrinsics.
type uint128 struct {
lo, hi uint64
}
func mul64(a, b uint64) uint128 {
hi, lo := bitsMul64(a, b)
return uint128{lo, hi}
}
func add128(a, b uint128) uint128 {
lo, c := bitsAdd64(a.lo, b.lo, 0)
hi, c := bitsAdd64(a.hi, b.hi, c)
if c != 0 {
panic("poly1305: unexpected overflow")
}
finalizeGeneric(out, &H, &(h.s))
return uint128{lo, hi}
}
func shiftRightBy2(a uint128) uint128 {
a.lo = a.lo>>2 | (a.hi&3)<<62
a.hi = a.hi >> 2
return a
}
func updateGeneric(msg []byte, flag uint32, h, r *[5]uint32) {
h0, h1, h2, h3, h4 := h[0], h[1], h[2], h[3], h[4]
r0, r1, r2, r3, r4 := uint64(r[0]), uint64(r[1]), uint64(r[2]), uint64(r[3]), uint64(r[4])
R1, R2, R3, R4 := r1*5, r2*5, r3*5, r4*5
for len(msg) >= TagSize {
// h += msg
h0 += binary.LittleEndian.Uint32(msg[0:]) & 0x3ffffff
h1 += (binary.LittleEndian.Uint32(msg[3:]) >> 2) & 0x3ffffff
h2 += (binary.LittleEndian.Uint32(msg[6:]) >> 4) & 0x3ffffff
h3 += (binary.LittleEndian.Uint32(msg[9:]) >> 6) & 0x3ffffff
h4 += (binary.LittleEndian.Uint32(msg[12:]) >> 8) | flag
// h *= r
d0 := (uint64(h0) * r0) + (uint64(h1) * R4) + (uint64(h2) * R3) + (uint64(h3) * R2) + (uint64(h4) * R1)
d1 := (d0 >> 26) + (uint64(h0) * r1) + (uint64(h1) * r0) + (uint64(h2) * R4) + (uint64(h3) * R3) + (uint64(h4) * R2)
d2 := (d1 >> 26) + (uint64(h0) * r2) + (uint64(h1) * r1) + (uint64(h2) * r0) + (uint64(h3) * R4) + (uint64(h4) * R3)
d3 := (d2 >> 26) + (uint64(h0) * r3) + (uint64(h1) * r2) + (uint64(h2) * r1) + (uint64(h3) * r0) + (uint64(h4) * R4)
d4 := (d3 >> 26) + (uint64(h0) * r4) + (uint64(h1) * r3) + (uint64(h2) * r2) + (uint64(h3) * r1) + (uint64(h4) * r0)
// h %= p
h0 = uint32(d0) & 0x3ffffff
h1 = uint32(d1) & 0x3ffffff
h2 = uint32(d2) & 0x3ffffff
h3 = uint32(d3) & 0x3ffffff
h4 = uint32(d4) & 0x3ffffff
h0 += uint32(d4>>26) * 5
h1 += h0 >> 26
h0 = h0 & 0x3ffffff
// updateGeneric absorbs msg into the state.h accumulator. For each chunk m of
// 128 bits of message, it computes
//
// h₊ = (h + m) * r mod 2¹³⁰ - 5
//
// If the msg length is not a multiple of TagSize, it assumes the last
// incomplete chunk is the final one.
func updateGeneric(state *macState, msg []byte) {
h0, h1, h2 := state.h[0], state.h[1], state.h[2]
r0, r1 := state.r[0], state.r[1]
for len(msg) > 0 {
var c uint64
// For the first step, h + m, we use a chain of bits.Add64 intrinsics.
// The resulting value of h might exceed 2¹³⁰ - 5, but will be partially
// reduced at the end of the multiplication below.
//
// The spec requires us to set a bit just above the message size, not to
// hide leading zeroes. For full chunks, that's 1 << 128, so we can just
// add 1 to the most significant (2¹²⁸) limb, h2.
if len(msg) >= TagSize {
h0, c = bitsAdd64(h0, binary.LittleEndian.Uint64(msg[0:8]), 0)
h1, c = bitsAdd64(h1, binary.LittleEndian.Uint64(msg[8:16]), c)
h2 += c + 1
msg = msg[TagSize:]
} else {
var buf [TagSize]byte
copy(buf[:], msg)
buf[len(msg)] = 1
h0, c = bitsAdd64(h0, binary.LittleEndian.Uint64(buf[0:8]), 0)
h1, c = bitsAdd64(h1, binary.LittleEndian.Uint64(buf[8:16]), c)
h2 += c
msg = nil
}
h[0], h[1], h[2], h[3], h[4] = h0, h1, h2, h3, h4
// Multiplication of big number limbs is similar to elementary school
// columnar multiplication. Instead of digits, there are 64-bit limbs.
//
// We are multiplying a 3 limbs number, h, by a 2 limbs number, r.
//
// h2 h1 h0 x
// r1 r0 =
// ----------------
// h2r0 h1r0 h0r0 <-- individual 128-bit products
// + h2r1 h1r1 h0r1
// ------------------------
// m3 m2 m1 m0 <-- result in 128-bit overlapping limbs
// ------------------------
// m3.hi m2.hi m1.hi m0.hi <-- carry propagation
// + m3.lo m2.lo m1.lo m0.lo
// -------------------------------
// t4 t3 t2 t1 t0 <-- final result in 64-bit limbs
//
// The main difference from pen-and-paper multiplication is that we do
// carry propagation in a separate step, as if we wrote two digit sums
// at first (the 128-bit limbs), and then carried the tens all at once.
h0r0 := mul64(h0, r0)
h1r0 := mul64(h1, r0)
h2r0 := mul64(h2, r0)
h0r1 := mul64(h0, r1)
h1r1 := mul64(h1, r1)
h2r1 := mul64(h2, r1)
// Since h2 is known to be at most 7 (5 + 1 + 1), and r0 and r1 have their
// top 4 bits cleared by rMask{0,1}, we know that their product is not going
// to overflow 64 bits, so we can ignore the high part of the products.
//
// This also means that the product doesn't have a fifth limb (t4).
if h2r0.hi != 0 {
panic("poly1305: unexpected overflow")
}
if h2r1.hi != 0 {
panic("poly1305: unexpected overflow")
}
m0 := h0r0
m1 := add128(h1r0, h0r1) // These two additions don't overflow thanks again
m2 := add128(h2r0, h1r1) // to the 4 masked bits at the top of r0 and r1.
m3 := h2r1
t0 := m0.lo
t1, c := bitsAdd64(m1.lo, m0.hi, 0)
t2, c := bitsAdd64(m2.lo, m1.hi, c)
t3, _ := bitsAdd64(m3.lo, m2.hi, c)
// Now we have the result as 4 64-bit limbs, and we need to reduce it
// modulo 2¹³⁰ - 5. The special shape of this Crandall prime lets us do
// a cheap partial reduction according to the reduction identity
//
// c * 2¹³⁰ + n = c * 5 + n mod 2¹³⁰ - 5
//
// because 2¹³⁰ = 5 mod 2¹³⁰ - 5. Partial reduction since the result is
// likely to be larger than 2¹³⁰ - 5, but still small enough to fit the
// assumptions we make about h in the rest of the code.
//
// See also https://speakerdeck.com/gtank/engineering-prime-numbers?slide=23
// We split the final result at the 2¹³⁰ mark into h and cc, the carry.
// Note that the carry bits are effectively shifted left by 2, in other
// words, cc = c * 4 for the c in the reduction identity.
h0, h1, h2 = t0, t1, t2&maskLow2Bits
cc := uint128{t2 & maskNotLow2Bits, t3}
// To add c * 5 to h, we first add cc = c * 4, and then add (cc >> 2) = c.
h0, c = bitsAdd64(h0, cc.lo, 0)
h1, c = bitsAdd64(h1, cc.hi, c)
h2 += c
cc = shiftRightBy2(cc)
h0, c = bitsAdd64(h0, cc.lo, 0)
h1, c = bitsAdd64(h1, cc.hi, c)
h2 += c
// h2 is at most 3 + 1 + 1 = 5, making the whole of h at most
//
// 5 * 2¹²⁸ + (2¹²⁸ - 1) = 6 * 2¹²⁸ - 1
}
state.h[0], state.h[1], state.h[2] = h0, h1, h2
}
func finalizeGeneric(out *[TagSize]byte, h *[5]uint32, s *[4]uint32) {
h0, h1, h2, h3, h4 := h[0], h[1], h[2], h[3], h[4]
// h %= p reduction
h2 += h1 >> 26
h1 &= 0x3ffffff
h3 += h2 >> 26
h2 &= 0x3ffffff
h4 += h3 >> 26
h3 &= 0x3ffffff
h0 += 5 * (h4 >> 26)
h4 &= 0x3ffffff
h1 += h0 >> 26
h0 &= 0x3ffffff
// h - p
t0 := h0 + 5
t1 := h1 + (t0 >> 26)
t2 := h2 + (t1 >> 26)
t3 := h3 + (t2 >> 26)
t4 := h4 + (t3 >> 26) - (1 << 26)
t0 &= 0x3ffffff
t1 &= 0x3ffffff
t2 &= 0x3ffffff
t3 &= 0x3ffffff
// select h if h < p else h - p
t_mask := (t4 >> 31) - 1
h_mask := ^t_mask
h0 = (h0 & h_mask) | (t0 & t_mask)
h1 = (h1 & h_mask) | (t1 & t_mask)
h2 = (h2 & h_mask) | (t2 & t_mask)
h3 = (h3 & h_mask) | (t3 & t_mask)
h4 = (h4 & h_mask) | (t4 & t_mask)
// h %= 2^128
h0 |= h1 << 26
h1 = ((h1 >> 6) | (h2 << 20))
h2 = ((h2 >> 12) | (h3 << 14))
h3 = ((h3 >> 18) | (h4 << 8))
// s: the s part of the key
// tag = (h + s) % (2^128)
t := uint64(h0) + uint64(s[0])
h0 = uint32(t)
t = uint64(h1) + uint64(s[1]) + (t >> 32)
h1 = uint32(t)
t = uint64(h2) + uint64(s[2]) + (t >> 32)
h2 = uint32(t)
t = uint64(h3) + uint64(s[3]) + (t >> 32)
h3 = uint32(t)
binary.LittleEndian.PutUint32(out[0:], h0)
binary.LittleEndian.PutUint32(out[4:], h1)
binary.LittleEndian.PutUint32(out[8:], h2)
binary.LittleEndian.PutUint32(out[12:], h3)
const (
maskLow2Bits uint64 = 0x0000000000000003
maskNotLow2Bits uint64 = ^maskLow2Bits
)
// select64 returns x if v == 1 and y if v == 0, in constant time.
func select64(v, x, y uint64) uint64 { return ^(v-1)&x | (v-1)&y }
// [p0, p1, p2] is 2¹³⁰ - 5 in little endian order.
const (
p0 = 0xFFFFFFFFFFFFFFFB
p1 = 0xFFFFFFFFFFFFFFFF
p2 = 0x0000000000000003
)
// finalize completes the modular reduction of h and computes
//
// out = h + s mod 2¹²⁸
//
func finalize(out *[TagSize]byte, h *[3]uint64, s *[2]uint64) {
h0, h1, h2 := h[0], h[1], h[2]
// After the partial reduction in updateGeneric, h might be more than
// 2¹³⁰ - 5, but will be less than 2 * (2¹³⁰ - 5). To complete the reduction
// in constant time, we compute t = h - (2¹³⁰ - 5), and select h as the
// result if the subtraction underflows, and t otherwise.
hMinusP0, b := bitsSub64(h0, p0, 0)
hMinusP1, b := bitsSub64(h1, p1, b)
_, b = bitsSub64(h2, p2, b)
// h = h if h < p else h - p
h0 = select64(b, h0, hMinusP0)
h1 = select64(b, h1, hMinusP1)
// Finally, we compute the last Poly1305 step
//
// tag = h + s mod 2¹²⁸
//
// by just doing a wide addition with the 128 low bits of h and discarding
// the overflow.
h0, c := bitsAdd64(h0, s[0], 0)
h1, _ = bitsAdd64(h1, s[1], c)
binary.LittleEndian.PutUint64(out[0:8], h0)
binary.LittleEndian.PutUint64(out[8:16], h1)
}
......@@ -6,10 +6,7 @@
package poly1305
// Sum generates an authenticator for msg using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[TagSize]byte, msg []byte, key *[32]byte) {
func sum(out *[TagSize]byte, msg []byte, key *[32]byte) {
h := newMAC(key)
h.Write(msg)
h.Sum(out)
......
......@@ -7,62 +7,52 @@
package poly1305
//go:noescape
func initialize(state *[7]uint64, key *[32]byte)
func update(state *macState, msg []byte)
//go:noescape
func update(state *[7]uint64, msg []byte)
//go:noescape
func finalize(tag *[TagSize]byte, state *[7]uint64)
// Sum generates an authenticator for m using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[16]byte, m []byte, key *[32]byte) {
func sum(out *[16]byte, m []byte, key *[32]byte) {
h := newMAC(key)
h.Write(m)
h.Sum(out)
}
func newMAC(key *[32]byte) (h mac) {
initialize(&h.state, key)
initialize(key, &h.r, &h.s)
return
}
type mac struct {
state [7]uint64 // := uint64{ h0, h1, h2, r0, r1, pad0, pad1 }
// mac is a wrapper for macGeneric that redirects calls that would have gone to
// updateGeneric to update.
//
// Its Write and Sum methods are otherwise identical to the macGeneric ones, but
// using function pointers would carry a major performance cost.
type mac struct{ macGeneric }
buffer [TagSize]byte
offset int
}
func (h *mac) Write(p []byte) (n int, err error) {
n = len(p)
func (h *mac) Write(p []byte) (int, error) {
nn := len(p)
if h.offset > 0 {
remaining := TagSize - h.offset
if n < remaining {
h.offset += copy(h.buffer[h.offset:], p)
return n, nil
n := copy(h.buffer[h.offset:], p)
if h.offset+n < TagSize {
h.offset += n
return nn, nil
}
copy(h.buffer[h.offset:], p[:remaining])
p = p[remaining:]
p = p[n:]
h.offset = 0
update(&h.state, h.buffer[:])
update(&h.macState, h.buffer[:])
}
if nn := len(p) - (len(p) % TagSize); nn > 0 {
update(&h.state, p[:nn])
p = p[nn:]
if n := len(p) - (len(p) % TagSize); n > 0 {
update(&h.macState, p[:n])
p = p[n:]
}
if len(p) > 0 {
h.offset += copy(h.buffer[h.offset:], p)
}
return n, nil
return nn, nil
}
func (h *mac) Sum(out *[16]byte) {
state := h.state
state := h.macState
if h.offset > 0 {
update(&state, h.buffer[:h.offset])
}
finalize(out, &state)
finalize(out, &state.h, &state.s)
}
......@@ -58,7 +58,6 @@ DATA ·poly1305Mask<>+0x08(SB)/8, $0x0FFFFFFC0FFFFFFC
GLOBL ·poly1305Mask<>(SB), RODATA, $16
// func update(state *[7]uint64, msg []byte)
TEXT ·update(SB), $0-32
MOVD state+0(FP), R3
MOVD msg_base+8(FP), R4
......@@ -180,68 +179,3 @@ done:
MOVD R9, 8(R3)
MOVD R10, 16(R3)
RET
// func initialize(state *[7]uint64, key *[32]byte)
TEXT ·initialize(SB), $0-16
MOVD state+0(FP), R3
MOVD key+8(FP), R4
// state[0...7] is initialized with zero
// Load key
MOVD 0(R4), R5
MOVD 8(R4), R6
MOVD 16(R4), R7
MOVD 24(R4), R8
// Address of key mask
MOVD poly1305Mask<>(SB), R9
// Save original key in state
MOVD R7, 40(R3)
MOVD R8, 48(R3)
// Get mask
MOVD (R9), R7
MOVD 8(R9), R8
// And with key
AND R5, R7, R5
AND R6, R8, R6
// Save masked key in state
MOVD R5, 24(R3)
MOVD R6, 32(R3)
RET
// func finalize(tag *[TagSize]byte, state *[7]uint64)
TEXT ·finalize(SB), $0-16
MOVD tag+0(FP), R3
MOVD state+8(FP), R4
// Get h0, h1, h2 from state
MOVD 0(R4), R5
MOVD 8(R4), R6
MOVD 16(R4), R7
// Save h0, h1
MOVD R5, R8
MOVD R6, R9
MOVD $3, R20
MOVD $-1, R21
SUBC $-5, R5
SUBE R21, R6
SUBE R20, R7
MOVD $0, R21
SUBZE R21
// Check for carry
CMP $0, R21
ISEL $2, R5, R8, R5
ISEL $2, R6, R9, R6
MOVD 40(R4), R8
MOVD 48(R4), R9
ADDC R8, R5
ADDE R9, R6
MOVD R5, 0(R3)
MOVD R6, 8(R3)
RET
......@@ -22,10 +22,7 @@ func poly1305vx(out *[16]byte, m *byte, mlen uint64, key *[32]byte)
//go:noescape
func poly1305vmsl(out *[16]byte, m *byte, mlen uint64, key *[32]byte)
// Sum generates an authenticator for m using a one-time key and puts the
// 16-byte result into out. Authenticating two different messages with the same
// key allows an attacker to forge messages at will.
func Sum(out *[16]byte, m []byte, key *[32]byte) {
func sum(out *[16]byte, m []byte, key *[32]byte) {
if cpu.S390X.HasVX {
var mPtr *byte
if len(m) > 0 {
......
# golang.org/x/crypto v0.0.0-20190611184440-5c40567a22f8
# golang.org/x/crypto v0.0.0-20191111213947-16651526fdb4
## explicit
golang.org/x/crypto/chacha20
golang.org/x/crypto/chacha20poly1305
golang.org/x/crypto/cryptobyte
golang.org/x/crypto/cryptobyte/asn1
golang.org/x/crypto/curve25519
golang.org/x/crypto/hkdf
golang.org/x/crypto/internal/chacha20
golang.org/x/crypto/internal/subtle
golang.org/x/crypto/poly1305
# golang.org/x/net v0.0.0-20191105084925-a882066a44e0
......
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