Merge pull request #2300 from thaJeztah/bump_golang_1.12.16

Update Golang 1.12.16, golang.org/x/crypto (CVE-2020-0601, CVE-2020-7919)

appveyor.yml

@@ -4,7 +4,7 @@ clone_folder: c:\gopath\src\github.com\docker\cli
 
 environment:
   GOPATH: c:\gopath
-  GOVERSION: 1.12.15
+  GOVERSION: 1.12.16
   DEPVERSION: v0.4.1
 
 install:

dockerfiles/Dockerfile.binary-native

@@ -1,4 +1,4 @@
-ARG GO_VERSION=1.12.15
+ARG GO_VERSION=1.12.16
 
 FROM    golang:${GO_VERSION}-alpine
 

dockerfiles/Dockerfile.cross

@@ -1,4 +1,4 @@
-ARG GO_VERSION=1.12.15
+ARG GO_VERSION=1.12.16
 
 FROM	dockercore/golang-cross:${GO_VERSION}
 ENV     DISABLE_WARN_OUTSIDE_CONTAINER=1

dockerfiles/Dockerfile.dev

@@ -1,4 +1,4 @@
-ARG GO_VERSION=1.12.15
+ARG GO_VERSION=1.12.16
 
 FROM    golang:${GO_VERSION}-alpine
 

dockerfiles/Dockerfile.e2e

@@ -1,4 +1,4 @@
-ARG GO_VERSION=1.12.15
+ARG GO_VERSION=1.12.16
 
 # Use Debian based image as docker-compose requires glibc.
 FROM golang:${GO_VERSION}

dockerfiles/Dockerfile.lint

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1.1.3-experimental
 
-ARG GO_VERSION=1.12.15
+ARG GO_VERSION=1.12.16
 ARG GOLANGCI_LINTER_SHA="v1.21.0"
 
 FROM    golang:${GO_VERSION}-alpine AS build

vendor.conf

@@ -71,7 +71,7 @@ github.com/tonistiigi/units                         6950e57a87eaf136bbe44ef2ec8e
 github.com/xeipuuv/gojsonpointer                    02993c407bfbf5f6dae44c4f4b1cf6a39b5fc5bb
 github.com/xeipuuv/gojsonreference                  bd5ef7bd5415a7ac448318e64f11a24cd21e594b
 github.com/xeipuuv/gojsonschema                     f971f3cd73b2899de6923801c147f075263e0c50 # v1.1.0
-golang.org/x/crypto                                 88737f569e3a9c7ab309cdc09a07fe7fc87233c3
+golang.org/x/crypto                                 69ecbb4d6d5dab05e49161c6e77ea40a030884e1
 golang.org/x/net                                    f3200d17e092c607f615320ecaad13d87ad9a2b3
 golang.org/x/oauth2                                 ef147856a6ddbb60760db74283d2424e98c87bff
 golang.org/x/sync                                   e225da77a7e68af35c70ccbf71af2b83e6acac3c

vendor/golang.org/x/crypto/chacha20/chacha_arm64.go

@@ -0,0 +1,17 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build go1.11
+// +build !gccgo,!appengine
+
+package chacha20
+
+const bufSize = 256
+
+//go:noescape
+func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32)
+
+func (c *Cipher) xorKeyStreamBlocks(dst, src []byte) {
+	xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter)
+}

vendor/golang.org/x/crypto/chacha20/chacha_generic.go

@@ -0,0 +1,364 @@
+// 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
+}

vendor/golang.org/x/crypto/chacha20/chacha_noasm.go

@@ -0,0 +1,13 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !arm64,!s390x,!ppc64le arm64,!go1.11 gccgo appengine
+
+package chacha20
+
+const bufSize = blockSize
+
+func (s *Cipher) xorKeyStreamBlocks(dst, src []byte) {
+	s.xorKeyStreamBlocksGeneric(dst, src)
+}

vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.go

@@ -0,0 +1,16 @@
+// 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)
+}

vendor/golang.org/x/crypto/chacha20/chacha_ppc64le.s

@@ -0,0 +1,449 @@
+// 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

vendor/golang.org/x/crypto/chacha20/chacha_s390x.go

@@ -0,0 +1,26 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build !gccgo,!appengine
+
+package chacha20
+
+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.
+//go:noescape
+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)
+	}
+}

vendor/golang.org/x/crypto/chacha20/chacha_s390x.s

@@ -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

vendor/golang.org/x/crypto/chacha20/xor.go

@@ -4,9 +4,7 @@
 
 package chacha20
 
-import (
+import "runtime"
-	"runtime"
-)
 
 // Platforms that have fast unaligned 32-bit little endian accesses.
 const unaligned = runtime.GOARCH == "386" ||

vendor/golang.org/x/crypto/curve25519/const_amd64.h

@@ -1,8 +0,0 @@
-// 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
-
-#define REDMASK51     0x0007FFFFFFFFFFFF

vendor/golang.org/x/crypto/curve25519/const_amd64.s

@@ -1,20 +0,0 @@
-// 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

vendor/golang.org/x/crypto/curve25519/cswap_amd64.s

@@ -1,65 +0,0 @@
-// 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

vendor/golang.org/x/crypto/curve25519/curve25519.go

@@ -1,834 +1,95 @@
-// 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
+// Package curve25519 provides an implementation of the X25519 function, which
-// non-amd64 platforms. The amd64 assembly does not support gccgo.
+// performs scalar multiplication on the elliptic curve known as Curve25519.
-// +build !amd64 gccgo appengine
+// See RFC 7748.
-
+package curve25519 // import "golang.org/x/crypto/curve25519"
-package curve25519
 
 import (
-	"encoding/binary"
+	"crypto/subtle"
+	"fmt"
 )
 
-// This code is a port of the public domain, "ref10" implementation of
+// ScalarMult sets dst to the product scalar * point.
-// curve25519 from SUPERCOP 20130419 by D. J. Bernstein.
+//
+// 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)
+}
 
-// fieldElement represents an element of the field GF(2^255 - 19). An element
+// ScalarBaseMult sets dst to the product scalar * base where base is the
-// t, entries t[0]...t[9], represents the integer t[0]+2^26 t[1]+2^51 t[2]+2^77
+// standard generator.
-// t[3]+2^102 t[4]+...+2^230 t[9]. Bounds on each t[i] vary depending on
+//
-// context.
+// It is recommended to use the X25519 function with Basepoint instead, as
-type fieldElement [10]int32
+// copying into fixed size arrays can lead to unexpected bugs.
+func ScalarBaseMult(dst, scalar *[32]byte) {
+	ScalarMult(dst, scalar, &basePoint)
+}
 
-func feZero(fe *fieldElement) {
+const (
-	for i := range fe {
+	// ScalarSize is the size of the scalar input to X25519.
-		fe[i] = 0
+	ScalarSize = 32
+	// PointSize is the size of the point input to X25519.
+	PointSize = 32
+)
+
+// Basepoint is the canonical Curve25519 generator.
+var Basepoint []byte
+
+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}
+
+func init() { Basepoint = basePoint[:] }
+
+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")
 	}
 }
 
-func feOne(fe *fieldElement) {
+// X25519 returns the result of the scalar multiplication (scalar * point),
-	feZero(fe)
+// according to RFC 7748, Section 5. scalar, point and the return value are
-	fe[0] = 1
+// slices of 32 bytes.
+//
+// scalar can be generated at random, for example with crypto/rand. point should
+// be either Basepoint or the output of another X25519 call.
+//
+// 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)
 }
 
-func feAdd(dst, a, b *fieldElement) {
+func x25519(dst *[32]byte, scalar, point []byte) ([]byte, error) {
-	for i := range dst {
+	var in [32]byte
-		dst[i] = a[i] + b[i]
+	if l := len(scalar); l != 32 {
+		return nil, fmt.Errorf("bad scalar length: %d, expected %d", l, 32)
 	}
-}
+	if l := len(point); l != 32 {
-
+		return nil, fmt.Errorf("bad point length: %d, expected %d", l, 32)
-func feSub(dst, a, b *fieldElement) {
+	}
-	for i := range dst {
+	copy(in[:], scalar)
-		dst[i] = a[i] - b[i]
+	if &point[0] == &Basepoint[0] {
-	}
+		checkBasepoint()
-}
+		ScalarBaseMult(dst, &in)
-
+	} else {
-func feCopy(dst, src *fieldElement) {
+		var base, zero [32]byte
-	for i := range dst {
+		copy(base[:], point)
-		dst[i] = src[i]
+		ScalarMult(dst, &in, &base)
-	}
+		if subtle.ConstantTimeCompare(dst[:], zero[:]) == 1 {
-}
+			return nil, fmt.Errorf("bad input point: low order point")
-
+		}
-// feCSwap replaces (f,g) with (g,f) if b == 1; replaces (f,g) with (f,g) if b == 0.
+	}
-//
+	return dst[:], nil
-// 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 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)
 }

vendor/golang.org/x/crypto/curve25519/curve25519_amd64.go

@@ -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
 

vendor/golang.org/x/crypto/curve25519/curve25519_amd64.s

@@ -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
@@ -121,18 +196,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -236,18 +311,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -441,18 +516,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -591,18 +666,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -731,18 +806,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -846,18 +921,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -996,18 +1071,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -1146,18 +1221,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -1332,18 +1407,18 @@ TEXT ·ladderstep(SB),0,$296-8
 	ADDQ AX,R12
 	ADCQ DX,R13
 	MOVQ $REDMASK51,DX
-	SHLQ $13,CX:SI
+	SHLQ $13,SI,CX
 	ANDQ DX,SI
-	SHLQ $13,R9:R8
+	SHLQ $13,R8,R9
 	ANDQ DX,R8
 	ADDQ CX,R8
-	SHLQ $13,R11:R10
+	SHLQ $13,R10,R11
 	ANDQ DX,R10
 	ADDQ R9,R10
-	SHLQ $13,R13:R12
+	SHLQ $13,R12,R13
 	ANDQ DX,R12
 	ADDQ R11,R12
-	SHLQ $13,R15:R14
+	SHLQ $13,R14,R15
 	ANDQ DX,R14
 	ADDQ R13,R14
 	IMUL3Q $19,R15,CX
@@ -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

vendor/golang.org/x/crypto/curve25519/curve25519_generic.go

@@ -0,0 +1,828 @@
+// 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)
+}

vendor/golang.org/x/crypto/curve25519/curve25519_noasm.go

@@ -0,0 +1,11 @@
+// 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 !amd64 gccgo appengine purego
+
+package curve25519
+
+func scalarMult(out, in, base *[32]byte) {
+	scalarMultGeneric(out, in, base)
+}

vendor/golang.org/x/crypto/curve25519/doc.go

@@ -1,23 +0,0 @@
-// 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)
-}

vendor/golang.org/x/crypto/curve25519/freeze_amd64.s

@@ -1,73 +0,0 @@
-// 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

vendor/golang.org/x/crypto/curve25519/mul_amd64.s

@@ -1,169 +0,0 @@
-// 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,R9:R8
-	ANDQ SI,R8
-	SHLQ $13,R11:R10
-	ANDQ SI,R10
-	ADDQ R9,R10
-	SHLQ $13,R13:R12
-	ANDQ SI,R12
-	ADDQ R11,R12
-	SHLQ $13,R15:R14
-	ANDQ SI,R14
-	ADDQ R13,R14
-	SHLQ $13,BP:BX
-	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

vendor/golang.org/x/crypto/curve25519/square_amd64.s

@@ -1,132 +0,0 @@
-// 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,R8:CX
-	ANDQ SI,CX
-	SHLQ $13,R10:R9
-	ANDQ SI,R9
-	ADDQ R8,R9
-	SHLQ $13,R12:R11
-	ANDQ SI,R11
-	ADDQ R10,R11
-	SHLQ $13,R14:R13
-	ANDQ SI,R13
-	ADDQ R12,R13
-	SHLQ $13,BX:R15
-	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

vendor/golang.org/x/crypto/ed25519/ed25519.go

@@ -2,6 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
+// In Go 1.13, the ed25519 package was promoted to the standard library as
+// crypto/ed25519, and this package became a wrapper for the standard library one.
+//
+// +build !go1.13
+
 // Package ed25519 implements the Ed25519 signature algorithm. See
 // https://ed25519.cr.yp.to/.
 //

vendor/golang.org/x/crypto/ed25519/ed25519_go113.go

@@ -0,0 +1,73 @@
+// 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 ed25519 implements the Ed25519 signature algorithm. See
+// https://ed25519.cr.yp.to/.
+//
+// These functions are also compatible with the “Ed25519” function defined in
+// RFC 8032. However, unlike RFC 8032's formulation, this package's private key
+// representation includes a public key suffix to make multiple signing
+// operations with the same key more efficient. This package refers to the RFC
+// 8032 private key as the “seed”.
+//
+// Beginning with Go 1.13, the functionality of this package was moved to the
+// standard library as crypto/ed25519. This package only acts as a compatibility
+// wrapper.
+package ed25519
+
+import (
+	"crypto/ed25519"
+	"io"
+)
+
+const (
+	// PublicKeySize is the size, in bytes, of public keys as used in this package.
+	PublicKeySize = 32
+	// PrivateKeySize is the size, in bytes, of private keys as used in this package.
+	PrivateKeySize = 64
+	// SignatureSize is the size, in bytes, of signatures generated and verified by this package.
+	SignatureSize = 64
+	// SeedSize is the size, in bytes, of private key seeds. These are the private key representations used by RFC 8032.
+	SeedSize = 32
+)
+
+// PublicKey is the type of Ed25519 public keys.
+//
+// This type is an alias for crypto/ed25519's PublicKey type.
+// See the crypto/ed25519 package for the methods on this type.
+type PublicKey = ed25519.PublicKey
+
+// PrivateKey is the type of Ed25519 private keys. It implements crypto.Signer.
+//
+// This type is an alias for crypto/ed25519's PrivateKey type.
+// See the crypto/ed25519 package for the methods on this type.
+type PrivateKey = ed25519.PrivateKey
+
+// GenerateKey generates a public/private key pair using entropy from rand.
+// If rand is nil, crypto/rand.Reader will be used.
+func GenerateKey(rand io.Reader) (PublicKey, PrivateKey, error) {
+	return ed25519.GenerateKey(rand)
+}
+
+// NewKeyFromSeed calculates a private key from a seed. It will panic if
+// len(seed) is not SeedSize. This function is provided for interoperability
+// with RFC 8032. RFC 8032's private keys correspond to seeds in this
+// package.
+func NewKeyFromSeed(seed []byte) PrivateKey {
+	return ed25519.NewKeyFromSeed(seed)
+}
+
+// Sign signs the message with privateKey and returns a signature. It will
+// panic if len(privateKey) is not PrivateKeySize.
+func Sign(privateKey PrivateKey, message []byte) []byte {
+	return ed25519.Sign(privateKey, message)
+}
+
+// Verify reports whether sig is a valid signature of message by publicKey. It
+// will panic if len(publicKey) is not PublicKeySize.
+func Verify(publicKey PublicKey, message, sig []byte) bool {
+	return ed25519.Verify(publicKey, message, sig)
+}

vendor/golang.org/x/crypto/go.mod

@@ -1,3 +1,8 @@
 module golang.org/x/crypto
 
-require golang.org/x/sys v0.0.0-20190403152447-81d4e9dc473e
+go 1.11
+
+require (
+	golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3
+	golang.org/x/sys v0.0.0-20190412213103-97732733099d
+)

vendor/golang.org/x/crypto/internal/chacha20/chacha_arm64.go

@@ -1,31 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build go1.11
-// +build !gccgo
-
-package chacha20
-
-const (
-	haveAsm = true
-	bufSize = 256
-)
-
-//go:noescape
-func xorKeyStreamVX(dst, src []byte, key *[8]uint32, nonce *[3]uint32, counter *uint32)
-
-func (c *Cipher) xorKeyStreamAsm(dst, src []byte) {
-
-	if len(src) >= bufSize {
-		xorKeyStreamVX(dst, src, &c.key, &c.nonce, &c.counter)
-	}
-
-	if len(src)%bufSize != 0 {
-		i := len(src) - len(src)%bufSize
-		c.buf = [bufSize]byte{}
-		copy(c.buf[:], src[i:])
-		xorKeyStreamVX(c.buf[:], c.buf[:], &c.key, &c.nonce, &c.counter)
-		c.len = bufSize - copy(dst[i:], c.buf[:len(src)%bufSize])
-	}
-}

vendor/golang.org/x/crypto/internal/chacha20/chacha_generic.go

@@ -1,264 +0,0 @@
-// Copyright 2016 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// 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
-}

vendor/golang.org/x/crypto/internal/chacha20/chacha_noasm.go

@@ -1,16 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build !arm64,!s390x arm64,!go1.11 gccgo appengine
-
-package chacha20
-
-const (
-	bufSize = 64
-	haveAsm = false
-)
-
-func (*Cipher) xorKeyStreamAsm(dst, src []byte) {
-	panic("not implemented")
-}

vendor/golang.org/x/crypto/internal/chacha20/chacha_s390x.go

@@ -1,29 +0,0 @@
-// Copyright 2018 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// +build s390x,!gccgo,!appengine
-
-package chacha20
-
-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.
-//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)
-}
-
-// EXRL targets, DO NOT CALL!
-func mvcSrcToBuf()
-func mvcBufToDst()

vendor/golang.org/x/crypto/poly1305/bits_compat.go

@@ -0,0 +1,39 @@
+// 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
+}

vendor/golang.org/x/crypto/poly1305/bits_go1.13.go

@@ -0,0 +1,21 @@
+// 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)
+}

vendor/golang.org/x/crypto/poly1305/mac_noasm.go

@@ -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,!ppc64le gccgo appengine
 
 package poly1305
 

vendor/golang.org/x/crypto/poly1305/poly1305.go

@@ -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
+// Sum generates an authenticator for msg using a one-time key and puts the
-// key.
+// 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)

vendor/golang.org/x/crypto/poly1305/sum_amd64.go

@@ -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 sum(out *[16]byte, m []byte, key *[32]byte) {
-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) {
 	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 {
+// mac is a wrapper for macGeneric that redirects calls that would have gone to
-	state [7]uint64 // := uint64{ h0, h1, h2, r0, r1, pad0, pad1 }
+// 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
+func (h *mac) Write(p []byte) (int, error) {
-	offset int
+	nn := len(p)
-}
-
-func (h *mac) Write(p []byte) (n int, err error) {
-	n = len(p)
 	if h.offset > 0 {
-		remaining := TagSize - h.offset
+		n := copy(h.buffer[h.offset:], p)
-		if n < remaining {
+		if h.offset+n < TagSize {
-			h.offset += copy(h.buffer[h.offset:], p)
+			h.offset += n
-			return n, nil
+			return nn, nil
 		}
-		copy(h.buffer[h.offset:], p[:remaining])
+		p = p[n:]
-		p = p[remaining:]
 		h.offset = 0
-		update(&h.state, h.buffer[:])
+		update(&h.macState, h.buffer[:])
 	}
-	if nn := len(p) - (len(p) % TagSize); nn > 0 {
+	if n := len(p) - (len(p) % TagSize); n > 0 {
-		update(&h.state, p[:nn])
+		update(&h.macState, p[:n])
-		p = p[nn:]
+		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)
 }

vendor/golang.org/x/crypto/poly1305/sum_amd64.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

vendor/golang.org/x/crypto/poly1305/sum_arm.go

@@ -1,22 +0,0 @@
-// Copyright 2015 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 arm,!gccgo,!appengine,!nacl
-
-package poly1305
-
-// This function 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) {
-	var mPtr *byte
-	if len(m) > 0 {
-		mPtr = &m[0]
-	}
-	poly1305_auth_armv6(out, mPtr, uint32(len(m)), key)
-}

vendor/golang.org/x/crypto/poly1305/sum_arm.s

@@ -1,427 +0,0 @@
-// Copyright 2015 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 arm,!gccgo,!appengine,!nacl
-
-#include "textflag.h"
-
-// This code was translated into a form compatible with 5a from the public
-// domain source by Andrew Moon: github.com/floodyberry/poly1305-opt/blob/master/app/extensions/poly1305.
-
-DATA ·poly1305_init_constants_armv6<>+0x00(SB)/4, $0x3ffffff
-DATA ·poly1305_init_constants_armv6<>+0x04(SB)/4, $0x3ffff03
-DATA ·poly1305_init_constants_armv6<>+0x08(SB)/4, $0x3ffc0ff
-DATA ·poly1305_init_constants_armv6<>+0x0c(SB)/4, $0x3f03fff
-DATA ·poly1305_init_constants_armv6<>+0x10(SB)/4, $0x00fffff
-GLOBL ·poly1305_init_constants_armv6<>(SB), 8, $20
-
-// Warning: the linker may use R11 to synthesize certain instructions. Please
-// take care and verify that no synthetic instructions use it.
-
-TEXT poly1305_init_ext_armv6<>(SB), NOSPLIT, $0
-	// Needs 16 bytes of stack and 64 bytes of space pointed to by R0.  (It
-	// might look like it's only 60 bytes of space but the final four bytes
-	// will be written by another function.) We need to skip over four
-	// bytes of stack because that's saving the value of 'g'.
-	ADD       $4, R13, R8
-	MOVM.IB   [R4-R7], (R8)
-	MOVM.IA.W (R1), [R2-R5]
-	MOVW      $·poly1305_init_constants_armv6<>(SB), R7
-	MOVW      R2, R8
-	MOVW      R2>>26, R9
-	MOVW      R3>>20, g
-	MOVW      R4>>14, R11
-	MOVW      R5>>8, R12
-	ORR       R3<<6, R9, R9
-	ORR       R4<<12, g, g
-	ORR       R5<<18, R11, R11
-	MOVM.IA   (R7), [R2-R6]
-	AND       R8, R2, R2
-	AND       R9, R3, R3
-	AND       g, R4, R4
-	AND       R11, R5, R5
-	AND       R12, R6, R6
-	MOVM.IA.W [R2-R6], (R0)
-	EOR       R2, R2, R2
-	EOR       R3, R3, R3
-	EOR       R4, R4, R4
-	EOR       R5, R5, R5
-	EOR       R6, R6, R6
-	MOVM.IA.W [R2-R6], (R0)
-	MOVM.IA.W (R1), [R2-R5]
-	MOVM.IA   [R2-R6], (R0)
-	ADD       $20, R13, R0
-	MOVM.DA   (R0), [R4-R7]
-	RET
-
-#define MOVW_UNALIGNED(Rsrc, Rdst, Rtmp, offset) \
-	MOVBU (offset+0)(Rsrc), Rtmp; \
-	MOVBU Rtmp, (offset+0)(Rdst); \
-	MOVBU (offset+1)(Rsrc), Rtmp; \
-	MOVBU Rtmp, (offset+1)(Rdst); \
-	MOVBU (offset+2)(Rsrc), Rtmp; \
-	MOVBU Rtmp, (offset+2)(Rdst); \
-	MOVBU (offset+3)(Rsrc), Rtmp; \
-	MOVBU Rtmp, (offset+3)(Rdst)
-
-TEXT poly1305_blocks_armv6<>(SB), NOSPLIT, $0
-	// Needs 24 bytes of stack for saved registers and then 88 bytes of
-	// scratch space after that. We assume that 24 bytes at (R13) have
-	// already been used: four bytes for the link register saved in the
-	// prelude of poly1305_auth_armv6, four bytes for saving the value of g
-	// in that function and 16 bytes of scratch space used around
-	// poly1305_finish_ext_armv6_skip1.
-	ADD     $24, R13, R12
-	MOVM.IB [R4-R8, R14], (R12)
-	MOVW    R0, 88(R13)
-	MOVW    R1, 92(R13)
-	MOVW    R2, 96(R13)
-	MOVW    R1, R14
-	MOVW    R2, R12
-	MOVW    56(R0), R8
-	WORD    $0xe1180008                // TST R8, R8 not working see issue 5921
-	EOR     R6, R6, R6
-	MOVW.EQ $(1<<24), R6
-	MOVW    R6, 84(R13)
-	ADD     $116, R13, g
-	MOVM.IA (R0), [R0-R9]
-	MOVM.IA [R0-R4], (g)
-	CMP     $16, R12
-	BLO     poly1305_blocks_armv6_done
-
-poly1305_blocks_armv6_mainloop:
-	WORD    $0xe31e0003                            // TST R14, #3 not working see issue 5921
-	BEQ     poly1305_blocks_armv6_mainloop_aligned
-	ADD     $100, R13, g
-	MOVW_UNALIGNED(R14, g, R0, 0)
-	MOVW_UNALIGNED(R14, g, R0, 4)
-	MOVW_UNALIGNED(R14, g, R0, 8)
-	MOVW_UNALIGNED(R14, g, R0, 12)
-	MOVM.IA (g), [R0-R3]
-	ADD     $16, R14
-	B       poly1305_blocks_armv6_mainloop_loaded
-
-poly1305_blocks_armv6_mainloop_aligned:
-	MOVM.IA.W (R14), [R0-R3]
-
-poly1305_blocks_armv6_mainloop_loaded:
-	MOVW    R0>>26, g
-	MOVW    R1>>20, R11
-	MOVW    R2>>14, R12
-	MOVW    R14, 92(R13)
-	MOVW    R3>>8, R4
-	ORR     R1<<6, g, g
-	ORR     R2<<12, R11, R11
-	ORR     R3<<18, R12, R12
-	BIC     $0xfc000000, R0, R0
-	BIC     $0xfc000000, g, g
-	MOVW    84(R13), R3
-	BIC     $0xfc000000, R11, R11
-	BIC     $0xfc000000, R12, R12
-	ADD     R0, R5, R5
-	ADD     g, R6, R6
-	ORR     R3, R4, R4
-	ADD     R11, R7, R7
-	ADD     $116, R13, R14
-	ADD     R12, R8, R8
-	ADD     R4, R9, R9
-	MOVM.IA (R14), [R0-R4]
-	MULLU   R4, R5, (R11, g)
-	MULLU   R3, R5, (R14, R12)
-	MULALU  R3, R6, (R11, g)
-	MULALU  R2, R6, (R14, R12)
-	MULALU  R2, R7, (R11, g)
-	MULALU  R1, R7, (R14, R12)
-	ADD     R4<<2, R4, R4
-	ADD     R3<<2, R3, R3
-	MULALU  R1, R8, (R11, g)
-	MULALU  R0, R8, (R14, R12)
-	MULALU  R0, R9, (R11, g)
-	MULALU  R4, R9, (R14, R12)
-	MOVW    g, 76(R13)
-	MOVW    R11, 80(R13)
-	MOVW    R12, 68(R13)
-	MOVW    R14, 72(R13)
-	MULLU   R2, R5, (R11, g)
-	MULLU   R1, R5, (R14, R12)
-	MULALU  R1, R6, (R11, g)
-	MULALU  R0, R6, (R14, R12)
-	MULALU  R0, R7, (R11, g)
-	MULALU  R4, R7, (R14, R12)
-	ADD     R2<<2, R2, R2
-	ADD     R1<<2, R1, R1
-	MULALU  R4, R8, (R11, g)
-	MULALU  R3, R8, (R14, R12)
-	MULALU  R3, R9, (R11, g)
-	MULALU  R2, R9, (R14, R12)
-	MOVW    g, 60(R13)
-	MOVW    R11, 64(R13)
-	MOVW    R12, 52(R13)
-	MOVW    R14, 56(R13)
-	MULLU   R0, R5, (R11, g)
-	MULALU  R4, R6, (R11, g)
-	MULALU  R3, R7, (R11, g)
-	MULALU  R2, R8, (R11, g)
-	MULALU  R1, R9, (R11, g)
-	ADD     $52, R13, R0
-	MOVM.IA (R0), [R0-R7]
-	MOVW    g>>26, R12
-	MOVW    R4>>26, R14
-	ORR     R11<<6, R12, R12
-	ORR     R5<<6, R14, R14
-	BIC     $0xfc000000, g, g
-	BIC     $0xfc000000, R4, R4
-	ADD.S   R12, R0, R0
-	ADC     $0, R1, R1
-	ADD.S   R14, R6, R6
-	ADC     $0, R7, R7
-	MOVW    R0>>26, R12
-	MOVW    R6>>26, R14
-	ORR     R1<<6, R12, R12
-	ORR     R7<<6, R14, R14
-	BIC     $0xfc000000, R0, R0
-	BIC     $0xfc000000, R6, R6
-	ADD     R14<<2, R14, R14
-	ADD.S   R12, R2, R2
-	ADC     $0, R3, R3
-	ADD     R14, g, g
-	MOVW    R2>>26, R12
-	MOVW    g>>26, R14
-	ORR     R3<<6, R12, R12
-	BIC     $0xfc000000, g, R5
-	BIC     $0xfc000000, R2, R7
-	ADD     R12, R4, R4
-	ADD     R14, R0, R0
-	MOVW    R4>>26, R12
-	BIC     $0xfc000000, R4, R8
-	ADD     R12, R6, R9
-	MOVW    96(R13), R12
-	MOVW    92(R13), R14
-	MOVW    R0, R6
-	CMP     $32, R12
-	SUB     $16, R12, R12
-	MOVW    R12, 96(R13)
-	BHS     poly1305_blocks_armv6_mainloop
-
-poly1305_blocks_armv6_done:
-	MOVW    88(R13), R12
-	MOVW    R5, 20(R12)
-	MOVW    R6, 24(R12)
-	MOVW    R7, 28(R12)
-	MOVW    R8, 32(R12)
-	MOVW    R9, 36(R12)
-	ADD     $48, R13, R0
-	MOVM.DA (R0), [R4-R8, R14]
-	RET
-
-#define MOVHUP_UNALIGNED(Rsrc, Rdst, Rtmp) \
-	MOVBU.P 1(Rsrc), Rtmp; \
-	MOVBU.P Rtmp, 1(Rdst); \
-	MOVBU.P 1(Rsrc), Rtmp; \
-	MOVBU.P Rtmp, 1(Rdst)
-
-#define MOVWP_UNALIGNED(Rsrc, Rdst, Rtmp) \
-	MOVHUP_UNALIGNED(Rsrc, Rdst, Rtmp); \
-	MOVHUP_UNALIGNED(Rsrc, Rdst, Rtmp)
-
-// func poly1305_auth_armv6(out *[16]byte, m *byte, mlen uint32, key *[32]key)
-TEXT ·poly1305_auth_armv6(SB), $196-16
-	// The value 196, just above, is the sum of 64 (the size of the context
-	// structure) and 132 (the amount of stack needed).
-	//
-	// At this point, the stack pointer (R13) has been moved down. It
-	// points to the saved link register and there's 196 bytes of free
-	// space above it.
-	//
-	// The stack for this function looks like:
-	//
-	// +---------------------
-	// |
-	// | 64 bytes of context structure
-	// |
-	// +---------------------
-	// |
-	// | 112 bytes for poly1305_blocks_armv6
-	// |
-	// +---------------------
-	// | 16 bytes of final block, constructed at
-	// | poly1305_finish_ext_armv6_skip8
-	// +---------------------
-	// | four bytes of saved 'g'
-	// +---------------------
-	// | lr, saved by prelude    <- R13 points here
-	// +---------------------
-	MOVW g, 4(R13)
-
-	MOVW out+0(FP), R4
-	MOVW m+4(FP), R5
-	MOVW mlen+8(FP), R6
-	MOVW key+12(FP), R7
-
-	ADD  $136, R13, R0 // 136 = 4 + 4 + 16 + 112
-	MOVW R7, R1
-
-	// poly1305_init_ext_armv6 will write to the stack from R13+4, but
-	// that's ok because none of the other values have been written yet.
-	BL    poly1305_init_ext_armv6<>(SB)
-	BIC.S $15, R6, R2
-	BEQ   poly1305_auth_armv6_noblocks
-	ADD   $136, R13, R0
-	MOVW  R5, R1
-	ADD   R2, R5, R5
-	SUB   R2, R6, R6
-	BL    poly1305_blocks_armv6<>(SB)
-
-poly1305_auth_armv6_noblocks:
-	ADD  $136, R13, R0
-	MOVW R5, R1
-	MOVW R6, R2
-	MOVW R4, R3
-
-	MOVW  R0, R5
-	MOVW  R1, R6
-	MOVW  R2, R7
-	MOVW  R3, R8
-	AND.S R2, R2, R2
-	BEQ   poly1305_finish_ext_armv6_noremaining
-	EOR   R0, R0
-	ADD   $8, R13, R9                           // 8 = offset to 16 byte scratch space
-	MOVW  R0, (R9)
-	MOVW  R0, 4(R9)
-	MOVW  R0, 8(R9)
-	MOVW  R0, 12(R9)
-	WORD  $0xe3110003                           // TST R1, #3 not working see issue 5921
-	BEQ   poly1305_finish_ext_armv6_aligned
-	WORD  $0xe3120008                           // TST R2, #8 not working see issue 5921
-	BEQ   poly1305_finish_ext_armv6_skip8
-	MOVWP_UNALIGNED(R1, R9, g)
-	MOVWP_UNALIGNED(R1, R9, g)
-
-poly1305_finish_ext_armv6_skip8:
-	WORD $0xe3120004                     // TST $4, R2 not working see issue 5921
-	BEQ  poly1305_finish_ext_armv6_skip4
-	MOVWP_UNALIGNED(R1, R9, g)
-
-poly1305_finish_ext_armv6_skip4:
-	WORD $0xe3120002                     // TST $2, R2 not working see issue 5921
-	BEQ  poly1305_finish_ext_armv6_skip2
-	MOVHUP_UNALIGNED(R1, R9, g)
-	B    poly1305_finish_ext_armv6_skip2
-
-poly1305_finish_ext_armv6_aligned:
-	WORD      $0xe3120008                             // TST R2, #8 not working see issue 5921
-	BEQ       poly1305_finish_ext_armv6_skip8_aligned
-	MOVM.IA.W (R1), [g-R11]
-	MOVM.IA.W [g-R11], (R9)
-
-poly1305_finish_ext_armv6_skip8_aligned:
-	WORD   $0xe3120004                             // TST $4, R2 not working see issue 5921
-	BEQ    poly1305_finish_ext_armv6_skip4_aligned
-	MOVW.P 4(R1), g
-	MOVW.P g, 4(R9)
-
-poly1305_finish_ext_armv6_skip4_aligned:
-	WORD    $0xe3120002                     // TST $2, R2 not working see issue 5921
-	BEQ     poly1305_finish_ext_armv6_skip2
-	MOVHU.P 2(R1), g
-	MOVH.P  g, 2(R9)
-
-poly1305_finish_ext_armv6_skip2:
-	WORD    $0xe3120001                     // TST $1, R2 not working see issue 5921
-	BEQ     poly1305_finish_ext_armv6_skip1
-	MOVBU.P 1(R1), g
-	MOVBU.P g, 1(R9)
-
-poly1305_finish_ext_armv6_skip1:
-	MOVW  $1, R11
-	MOVBU R11, 0(R9)
-	MOVW  R11, 56(R5)
-	MOVW  R5, R0
-	ADD   $8, R13, R1
-	MOVW  $16, R2
-	BL    poly1305_blocks_armv6<>(SB)
-
-poly1305_finish_ext_armv6_noremaining:
-	MOVW      20(R5), R0
-	MOVW      24(R5), R1
-	MOVW      28(R5), R2
-	MOVW      32(R5), R3
-	MOVW      36(R5), R4
-	MOVW      R4>>26, R12
-	BIC       $0xfc000000, R4, R4
-	ADD       R12<<2, R12, R12
-	ADD       R12, R0, R0
-	MOVW      R0>>26, R12
-	BIC       $0xfc000000, R0, R0
-	ADD       R12, R1, R1
-	MOVW      R1>>26, R12
-	BIC       $0xfc000000, R1, R1
-	ADD       R12, R2, R2
-	MOVW      R2>>26, R12
-	BIC       $0xfc000000, R2, R2
-	ADD       R12, R3, R3
-	MOVW      R3>>26, R12
-	BIC       $0xfc000000, R3, R3
-	ADD       R12, R4, R4
-	ADD       $5, R0, R6
-	MOVW      R6>>26, R12
-	BIC       $0xfc000000, R6, R6
-	ADD       R12, R1, R7
-	MOVW      R7>>26, R12
-	BIC       $0xfc000000, R7, R7
-	ADD       R12, R2, g
-	MOVW      g>>26, R12
-	BIC       $0xfc000000, g, g
-	ADD       R12, R3, R11
-	MOVW      $-(1<<26), R12
-	ADD       R11>>26, R12, R12
-	BIC       $0xfc000000, R11, R11
-	ADD       R12, R4, R9
-	MOVW      R9>>31, R12
-	SUB       $1, R12
-	AND       R12, R6, R6
-	AND       R12, R7, R7
-	AND       R12, g, g
-	AND       R12, R11, R11
-	AND       R12, R9, R9
-	MVN       R12, R12
-	AND       R12, R0, R0
-	AND       R12, R1, R1
-	AND       R12, R2, R2
-	AND       R12, R3, R3
-	AND       R12, R4, R4
-	ORR       R6, R0, R0
-	ORR       R7, R1, R1
-	ORR       g, R2, R2
-	ORR       R11, R3, R3
-	ORR       R9, R4, R4
-	ORR       R1<<26, R0, R0
-	MOVW      R1>>6, R1
-	ORR       R2<<20, R1, R1
-	MOVW      R2>>12, R2
-	ORR       R3<<14, R2, R2
-	MOVW      R3>>18, R3
-	ORR       R4<<8, R3, R3
-	MOVW      40(R5), R6
-	MOVW      44(R5), R7
-	MOVW      48(R5), g
-	MOVW      52(R5), R11
-	ADD.S     R6, R0, R0
-	ADC.S     R7, R1, R1
-	ADC.S     g, R2, R2
-	ADC.S     R11, R3, R3
-	MOVM.IA   [R0-R3], (R8)
-	MOVW      R5, R12
-	EOR       R0, R0, R0
-	EOR       R1, R1, R1
-	EOR       R2, R2, R2
-	EOR       R3, R3, R3
-	EOR       R4, R4, R4
-	EOR       R5, R5, R5
-	EOR       R6, R6, R6
-	EOR       R7, R7, R7
-	MOVM.IA.W [R0-R7], (R12)
-	MOVM.IA   [R0-R7], (R12)
-	MOVW      4(R13), g
-	RET

vendor/golang.org/x/crypto/poly1305/sum_generic.go

@@ -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 (
+// Poly1305 [RFC 7539] is a relatively simple algorithm: the authentication tag
-	msgBlock   = uint32(1 << 24)
+// for a 64 bytes message is approximately
-	finalBlock = uint32(0)
+//
-)
+//     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
+	initialize(key, &h.r, &h.s)
-	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:])
 	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
+	macState
-	s    [4]uint32
 
 	buffer [TagSize]byte
 	offset int
 }
 
-func (h *macGeneric) Write(p []byte) (n int, err error) {
+// Write splits the incoming message into TagSize chunks, and passes them to
-	n = len(p)
+// update. It buffers incomplete chunks.
+func (h *macGeneric) Write(p []byte) (int, error) {
+	nn := len(p)
 	if h.offset > 0 {
-		remaining := TagSize - h.offset
+		n := copy(h.buffer[h.offset:], p)
-		if n < remaining {
+		if h.offset+n < TagSize {
-			h.offset += copy(h.buffer[h.offset:], p)
+			h.offset += n
-			return n, nil
+			return nn, nil
 		}
-		copy(h.buffer[h.offset:], p[:remaining])
+		p = p[n:]
-		p = p[remaining:]
 		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 {
+	if n := len(p) - (len(p) % TagSize); n > 0 {
-		updateGeneric(p, msgBlock, &(h.h), &(h.r))
+		updateGeneric(&h.macState, p[:n])
-		p = p[nn:]
+		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) {
+// Sum flushes the last incomplete chunk from the buffer, if any, and generates
-	H, R := h.h, h.r
+// 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
+		updateGeneric(&state, h.buffer[:h.offset])
-		copy(buffer[:], h.buffer[:h.offset])
-		buffer[h.offset] = 1 // invariant: h.offset < TagSize
-		updateGeneric(buffer[:], finalBlock, &H, &R)
 	}
-	finalizeGeneric(out, &H, &(h.s))
+	finalize(out, &state.h, &state.s)
 }
 
-func updateGeneric(msg []byte, flag uint32, h, r *[5]uint32) {
+// [rMask0, rMask1] is the specified Poly1305 clamping mask in little-endian. It
-	h0, h1, h2, h3, h4 := h[0], h[1], h[2], h[3], h[4]
+// clears some bits of the secret coefficient to make it possible to implement
-	r0, r1, r2, r3, r4 := uint64(r[0]), uint64(r[1]), uint64(r[2]), uint64(r[3]), uint64(r[4])
+// multiplication more efficiently.
-	R1, R2, R3, R4 := r1*5, r2*5, r3*5, r4*5
+const (
+	rMask0 = 0x0FFFFFFC0FFFFFFF
+	rMask1 = 0x0FFFFFFC0FFFFFFC
+)
 
-	for len(msg) >= TagSize {
+func initialize(key *[32]byte, r, s *[2]uint64) {
-		// h += msg
+	r[0] = binary.LittleEndian.Uint64(key[0:8]) & rMask0
-		h0 += binary.LittleEndian.Uint32(msg[0:]) & 0x3ffffff
+	r[1] = binary.LittleEndian.Uint64(key[8:16]) & rMask1
-		h1 += (binary.LittleEndian.Uint32(msg[3:]) >> 2) & 0x3ffffff
+	s[0] = binary.LittleEndian.Uint64(key[16:24])
-		h2 += (binary.LittleEndian.Uint32(msg[6:]) >> 4) & 0x3ffffff
+	s[1] = binary.LittleEndian.Uint64(key[24:32])
-		h3 += (binary.LittleEndian.Uint32(msg[9:]) >> 6) & 0x3ffffff
+}
-		h4 += (binary.LittleEndian.Uint32(msg[12:]) >> 8) | flag
 
-		// h *= r
+// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
-		d0 := (uint64(h0) * r0) + (uint64(h1) * R4) + (uint64(h2) * R3) + (uint64(h3) * R2) + (uint64(h4) * R1)
+// bits.Mul64 and bits.Add64 intrinsics.
-		d1 := (d0 >> 26) + (uint64(h0) * r1) + (uint64(h1) * r0) + (uint64(h2) * R4) + (uint64(h3) * R3) + (uint64(h4) * R2)
+type uint128 struct {
-		d2 := (d1 >> 26) + (uint64(h0) * r2) + (uint64(h1) * r1) + (uint64(h2) * r0) + (uint64(h3) * R4) + (uint64(h4) * R3)
+	lo, hi uint64
-		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
+func mul64(a, b uint64) uint128 {
-		h0 = uint32(d0) & 0x3ffffff
+	hi, lo := bitsMul64(a, b)
-		h1 = uint32(d1) & 0x3ffffff
+	return uint128{lo, hi}
-		h2 = uint32(d2) & 0x3ffffff
+}
-		h3 = uint32(d3) & 0x3ffffff
-		h4 = uint32(d4) & 0x3ffffff
 
-		h0 += uint32(d4>>26) * 5
+func add128(a, b uint128) uint128 {
-		h1 += h0 >> 26
+	lo, c := bitsAdd64(a.lo, b.lo, 0)
-		h0 = h0 & 0x3ffffff
+	hi, c := bitsAdd64(a.hi, b.hi, c)
+	if c != 0 {
+		panic("poly1305: unexpected overflow")
+	}
+	return uint128{lo, hi}
+}
 
-		msg = msg[TagSize:]
+func shiftRightBy2(a uint128) uint128 {
+	a.lo = a.lo>>2 | (a.hi&3)<<62
+	a.hi = a.hi >> 2
+	return a
+}
+
+// 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
+		}
+
+		// 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
 	}
 
-	h[0], h[1], h[2], h[3], h[4] = h0, h1, h2, h3, h4
+	state.h[0], state.h[1], state.h[2] = h0, h1, h2
 }
 
-func finalizeGeneric(out *[TagSize]byte, h *[5]uint32, s *[4]uint32) {
+const (
-	h0, h1, h2, h3, h4 := h[0], h[1], h[2], h[3], h[4]
+	maskLow2Bits    uint64 = 0x0000000000000003
+	maskNotLow2Bits uint64 = ^maskLow2Bits
+)
 
-	// h %= p reduction
+// select64 returns x if v == 1 and y if v == 0, in constant time.
-	h2 += h1 >> 26
+func select64(v, x, y uint64) uint64 { return ^(v-1)&x | (v-1)&y }
-	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
+// [p0, p1, p2] is 2¹³⁰ - 5 in little endian order.
-	t0 := h0 + 5
+const (
-	t1 := h1 + (t0 >> 26)
+	p0 = 0xFFFFFFFFFFFFFFFB
-	t2 := h2 + (t1 >> 26)
+	p1 = 0xFFFFFFFFFFFFFFFF
-	t3 := h3 + (t2 >> 26)
+	p2 = 0x0000000000000003
-	t4 := h4 + (t3 >> 26) - (1 << 26)
+)
-	t0 &= 0x3ffffff
-	t1 &= 0x3ffffff
-	t2 &= 0x3ffffff
-	t3 &= 0x3ffffff
 
-	// select h if h < p else h - p
+// finalize completes the modular reduction of h and computes
-	t_mask := (t4 >> 31) - 1
+//
-	h_mask := ^t_mask
+//     out = h + s  mod  2¹²⁸
-	h0 = (h0 & h_mask) | (t0 & t_mask)
+//
-	h1 = (h1 & h_mask) | (t1 & t_mask)
+func finalize(out *[TagSize]byte, h *[3]uint64, s *[2]uint64) {
-	h2 = (h2 & h_mask) | (t2 & t_mask)
+	h0, h1, h2 := h[0], h[1], h[2]
-	h3 = (h3 & h_mask) | (t3 & t_mask)
-	h4 = (h4 & h_mask) | (t4 & t_mask)
 
-	// h %= 2^128
+	// After the partial reduction in updateGeneric, h might be more than
-	h0 |= h1 << 26
+	// 2¹³⁰ - 5, but will be less than 2 * (2¹³⁰ - 5). To complete the reduction
-	h1 = ((h1 >> 6) | (h2 << 20))
+	// in constant time, we compute t = h - (2¹³⁰ - 5), and select h as the
-	h2 = ((h2 >> 12) | (h3 << 14))
+	// result if the subtraction underflows, and t otherwise.
-	h3 = ((h3 >> 18) | (h4 << 8))
 
-	// s: the s part of the key
+	hMinusP0, b := bitsSub64(h0, p0, 0)
-	// tag = (h + s) % (2^128)
+	hMinusP1, b := bitsSub64(h1, p1, b)
-	t := uint64(h0) + uint64(s[0])
+	_, b = bitsSub64(h2, p2, b)
-	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)
+	// h = h if h < p else h - p
-	binary.LittleEndian.PutUint32(out[4:], h1)
+	h0 = select64(b, h0, hMinusP0)
-	binary.LittleEndian.PutUint32(out[8:], h2)
+	h1 = select64(b, h1, hMinusP1)
-	binary.LittleEndian.PutUint32(out[12:], h3)
+
+	// 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)
 }

vendor/golang.org/x/crypto/poly1305/sum_noasm.go

@@ -2,14 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-// +build s390x,!go1.11 !arm,!amd64,!s390x gccgo appengine nacl
+// +build s390x,!go1.11 !amd64,!s390x,!ppc64le gccgo appengine nacl
 
 package poly1305
 
-// Sum generates an authenticator for msg using a one-time key and puts the
+func sum(out *[TagSize]byte, msg []byte, key *[32]byte) {
-// 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) {
 	h := newMAC(key)
 	h.Write(msg)
 	h.Sum(out)

vendor/golang.org/x/crypto/poly1305/sum_ppc64le.go

@@ -0,0 +1,58 @@
+// 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 poly1305
+
+//go:noescape
+func update(state *macState, msg []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(key, &h.r, &h.s)
+	return
+}
+
+// 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 }
+
+func (h *mac) Write(p []byte) (int, error) {
+	nn := len(p)
+	if h.offset > 0 {
+		n := copy(h.buffer[h.offset:], p)
+		if h.offset+n < TagSize {
+			h.offset += n
+			return nn, nil
+		}
+		p = p[n:]
+		h.offset = 0
+		update(&h.macState, h.buffer[:])
+	}
+	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 nn, nil
+}
+
+func (h *mac) Sum(out *[16]byte) {
+	state := h.macState
+	if h.offset > 0 {
+		update(&state, h.buffer[:h.offset])
+	}
+	finalize(out, &state.h, &state.s)
+}

vendor/golang.org/x/crypto/poly1305/sum_ppc64le.s

@@ -0,0 +1,181 @@
+// 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
+
+#include "textflag.h"
+
+// This was ported from the amd64 implementation.
+
+#define POLY1305_ADD(msg, h0, h1, h2, t0, t1, t2) \
+	MOVD (msg), t0;  \
+	MOVD 8(msg), t1; \
+	MOVD $1, t2;     \
+	ADDC t0, h0, h0; \
+	ADDE t1, h1, h1; \
+	ADDE t2, h2;     \
+	ADD  $16, msg
+
+#define POLY1305_MUL(h0, h1, h2, r0, r1, t0, t1, t2, t3, t4, t5) \
+	MULLD  r0, h0, t0;  \
+	MULLD  r0, h1, t4;  \
+	MULHDU r0, h0, t1;  \
+	MULHDU r0, h1, t5;  \
+	ADDC   t4, t1, t1;  \
+	MULLD  r0, h2, t2;  \
+	ADDZE  t5;          \
+	MULHDU r1, h0, t4;  \
+	MULLD  r1, h0, h0;  \
+	ADD    t5, t2, t2;  \
+	ADDC   h0, t1, t1;  \
+	MULLD  h2, r1, t3;  \
+	ADDZE  t4, h0;      \
+	MULHDU r1, h1, t5;  \
+	MULLD  r1, h1, t4;  \
+	ADDC   t4, t2, t2;  \
+	ADDE   t5, t3, t3;  \
+	ADDC   h0, t2, t2;  \
+	MOVD   $-4, t4;     \
+	MOVD   t0, h0;      \
+	MOVD   t1, h1;      \
+	ADDZE  t3;          \
+	ANDCC  $3, t2, h2;  \
+	AND    t2, t4, t0;  \
+	ADDC   t0, h0, h0;  \
+	ADDE   t3, h1, h1;  \
+	SLD    $62, t3, t4; \
+	SRD    $2, t2;      \
+	ADDZE  h2;          \
+	OR     t4, t2, t2;  \
+	SRD    $2, t3;      \
+	ADDC   t2, h0, h0;  \
+	ADDE   t3, h1, h1;  \
+	ADDZE  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
+	MOVD state+0(FP), R3
+	MOVD msg_base+8(FP), R4
+	MOVD msg_len+16(FP), R5
+
+	MOVD 0(R3), R8   // h0
+	MOVD 8(R3), R9   // h1
+	MOVD 16(R3), R10 // h2
+	MOVD 24(R3), R11 // r0
+	MOVD 32(R3), R12 // r1
+
+	CMP R5, $16
+	BLT bytes_between_0_and_15
+
+loop:
+	POLY1305_ADD(R4, R8, R9, R10, R20, R21, R22)
+
+multiply:
+	POLY1305_MUL(R8, R9, R10, R11, R12, R16, R17, R18, R14, R20, R21)
+	ADD $-16, R5
+	CMP R5, $16
+	BGE loop
+
+bytes_between_0_and_15:
+	CMP  $0, R5
+	BEQ  done
+	MOVD $0, R16 // h0
+	MOVD $0, R17 // h1
+
+flush_buffer:
+	CMP R5, $8
+	BLE just1
+
+	MOVD $8, R21
+	SUB  R21, R5, R21
+
+	// Greater than 8 -- load the rightmost remaining bytes in msg
+	// and put into R17 (h1)
+	MOVD (R4)(R21), R17
+	MOVD $16, R22
+
+	// Find the offset to those bytes
+	SUB R5, R22, R22
+	SLD $3, R22
+
+	// Shift to get only the bytes in msg
+	SRD R22, R17, R17
+
+	// Put 1 at high end
+	MOVD $1, R23
+	SLD  $3, R21
+	SLD  R21, R23, R23
+	OR   R23, R17, R17
+
+	// Remainder is 8
+	MOVD $8, R5
+
+just1:
+	CMP R5, $8
+	BLT less8
+
+	// Exactly 8
+	MOVD (R4), R16
+
+	CMP $0, R17
+
+	// Check if we've already set R17; if not
+	// set 1 to indicate end of msg.
+	BNE  carry
+	MOVD $1, R17
+	BR   carry
+
+less8:
+	MOVD  $0, R16   // h0
+	MOVD  $0, R22   // shift count
+	CMP   R5, $4
+	BLT   less4
+	MOVWZ (R4), R16
+	ADD   $4, R4
+	ADD   $-4, R5
+	MOVD  $32, R22
+
+less4:
+	CMP   R5, $2
+	BLT   less2
+	MOVHZ (R4), R21
+	SLD   R22, R21, R21
+	OR    R16, R21, R16
+	ADD   $16, R22
+	ADD   $-2, R5
+	ADD   $2, R4
+
+less2:
+	CMP   $0, R5
+	BEQ   insert1
+	MOVBZ (R4), R21
+	SLD   R22, R21, R21
+	OR    R16, R21, R16
+	ADD   $8, R22
+
+insert1:
+	// Insert 1 at end of msg
+	MOVD $1, R21
+	SLD  R22, R21, R21
+	OR   R16, R21, R16
+
+carry:
+	// Add new values to h0, h1, h2
+	ADDC R16, R8
+	ADDE R17, R9
+	ADDE $0, R10
+	MOVD $16, R5
+	ADD  R5, R4
+	BR   multiply
+
+done:
+	// Save h0, h1, h2 in state
+	MOVD R8, 0(R3)
+	MOVD R9, 8(R3)
+	MOVD R10, 16(R3)
+	RET

vendor/golang.org/x/crypto/poly1305/sum_s390x.go

@@ -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
+func sum(out *[16]byte, m []byte, key *[32]byte) {
-// 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) {
 	if cpu.S390X.HasVX {
 		var mPtr *byte
 		if len(m) > 0 {

vendor/golang.org/x/crypto/ssh/certs.go

@@ -17,12 +17,14 @@ import (
 // These constants from [PROTOCOL.certkeys] represent the algorithm names
 // for certificate types supported by this package.
 const (
-	CertAlgoRSAv01      = "ssh-rsa-cert-v01@openssh.com"
+	CertAlgoRSAv01        = "ssh-rsa-cert-v01@openssh.com"
-	CertAlgoDSAv01      = "ssh-dss-cert-v01@openssh.com"
+	CertAlgoDSAv01        = "ssh-dss-cert-v01@openssh.com"
-	CertAlgoECDSA256v01 = "ecdsa-sha2-nistp256-cert-v01@openssh.com"
+	CertAlgoECDSA256v01   = "ecdsa-sha2-nistp256-cert-v01@openssh.com"
-	CertAlgoECDSA384v01 = "ecdsa-sha2-nistp384-cert-v01@openssh.com"
+	CertAlgoECDSA384v01   = "ecdsa-sha2-nistp384-cert-v01@openssh.com"
-	CertAlgoECDSA521v01 = "ecdsa-sha2-nistp521-cert-v01@openssh.com"
+	CertAlgoECDSA521v01   = "ecdsa-sha2-nistp521-cert-v01@openssh.com"
-	CertAlgoED25519v01  = "ssh-ed25519-cert-v01@openssh.com"
+	CertAlgoSKECDSA256v01 = "sk-ecdsa-sha2-nistp256-cert-v01@openssh.com"
+	CertAlgoED25519v01    = "ssh-ed25519-cert-v01@openssh.com"
+	CertAlgoSKED25519v01  = "sk-ssh-ed25519-cert-v01@openssh.com"
 )
 
 // Certificate types distinguish between host and user
@@ -37,6 +39,7 @@ const (
 type Signature struct {
 	Format string
 	Blob   []byte
+	Rest   []byte `ssh:"rest"`
 }
 
 // CertTimeInfinity can be used for OpenSSHCertV01.ValidBefore to indicate that
@@ -429,12 +432,14 @@ func (c *Certificate) SignCert(rand io.Reader, authority Signer) error {
 }
 
 var certAlgoNames = map[string]string{
-	KeyAlgoRSA:      CertAlgoRSAv01,
+	KeyAlgoRSA:        CertAlgoRSAv01,
-	KeyAlgoDSA:      CertAlgoDSAv01,
+	KeyAlgoDSA:        CertAlgoDSAv01,
-	KeyAlgoECDSA256: CertAlgoECDSA256v01,
+	KeyAlgoECDSA256:   CertAlgoECDSA256v01,
-	KeyAlgoECDSA384: CertAlgoECDSA384v01,
+	KeyAlgoECDSA384:   CertAlgoECDSA384v01,
-	KeyAlgoECDSA521: CertAlgoECDSA521v01,
+	KeyAlgoECDSA521:   CertAlgoECDSA521v01,
-	KeyAlgoED25519:  CertAlgoED25519v01,
+	KeyAlgoSKECDSA256: CertAlgoSKECDSA256v01,
+	KeyAlgoED25519:    CertAlgoED25519v01,
+	KeyAlgoSKED25519:  CertAlgoSKED25519v01,
 }
 
 // certToPrivAlgo returns the underlying algorithm for a certificate algorithm.
@@ -518,6 +523,12 @@ func parseSignatureBody(in []byte) (out *Signature, rest []byte, ok bool) {
 		return
 	}
 
+	switch out.Format {
+	case KeyAlgoSKECDSA256, CertAlgoSKECDSA256v01, KeyAlgoSKED25519, CertAlgoSKED25519v01:
+		out.Rest = in
+		return out, nil, ok
+	}
+
 	return out, in, ok
 }
 

vendor/golang.org/x/crypto/ssh/cipher.go

@@ -16,9 +16,8 @@ import (
 	"hash"
 	"io"
 	"io/ioutil"
-	"math/bits"
 
-	"golang.org/x/crypto/internal/chacha20"
+	"golang.org/x/crypto/chacha20"
 	"golang.org/x/crypto/poly1305"
 )
 
@@ -642,8 +641,8 @@ const chacha20Poly1305ID = "chacha20-poly1305@openssh.com"
 // the methods here also implement padding, which RFC4253 Section 6
 // also requires of stream ciphers.
 type chacha20Poly1305Cipher struct {
-	lengthKey  [8]uint32
+	lengthKey  [32]byte
-	contentKey [8]uint32
+	contentKey [32]byte
 	buf        []byte
 }
 
@@ -656,21 +655,21 @@ func newChaCha20Cipher(key, unusedIV, unusedMACKey []byte, unusedAlgs directionA
 		buf: make([]byte, 256),
 	}
 
-	for i := range c.contentKey {
+	copy(c.contentKey[:], key[:32])
-		c.contentKey[i] = binary.LittleEndian.Uint32(key[i*4 : (i+1)*4])
+	copy(c.lengthKey[:], key[32:])
-	}
-	for i := range c.lengthKey {
-		c.lengthKey[i] = binary.LittleEndian.Uint32(key[(i+8)*4 : (i+9)*4])
-	}
 	return c, nil
 }
 
 func (c *chacha20Poly1305Cipher) readCipherPacket(seqNum uint32, r io.Reader) ([]byte, error) {
-	nonce := [3]uint32{0, 0, bits.ReverseBytes32(seqNum)}
+	nonce := make([]byte, 12)
-	s := chacha20.New(c.contentKey, nonce)
+	binary.BigEndian.PutUint32(nonce[8:], seqNum)
-	var polyKey [32]byte
+	s, err := chacha20.NewUnauthenticatedCipher(c.contentKey[:], nonce)
+	if err != nil {
+		return nil, err
+	}
+	var polyKey, discardBuf [32]byte
 	s.XORKeyStream(polyKey[:], polyKey[:])
-	s.Advance() // skip next 32 bytes
+	s.XORKeyStream(discardBuf[:], discardBuf[:]) // skip the next 32 bytes
 
 	encryptedLength := c.buf[:4]
 	if _, err := io.ReadFull(r, encryptedLength); err != nil {
@@ -678,7 +677,11 @@ func (c *chacha20Poly1305Cipher) readCipherPacket(seqNum uint32, r io.Reader) ([
 	}
 
 	var lenBytes [4]byte
-	chacha20.New(c.lengthKey, nonce).XORKeyStream(lenBytes[:], encryptedLength)
+	ls, err := chacha20.NewUnauthenticatedCipher(c.lengthKey[:], nonce)
+	if err != nil {
+		return nil, err
+	}
+	ls.XORKeyStream(lenBytes[:], encryptedLength)
 
 	length := binary.BigEndian.Uint32(lenBytes[:])
 	if length > maxPacket {
@@ -724,11 +727,15 @@ func (c *chacha20Poly1305Cipher) readCipherPacket(seqNum uint32, r io.Reader) ([
 }
 
 func (c *chacha20Poly1305Cipher) writeCipherPacket(seqNum uint32, w io.Writer, rand io.Reader, payload []byte) error {
-	nonce := [3]uint32{0, 0, bits.ReverseBytes32(seqNum)}
+	nonce := make([]byte, 12)
-	s := chacha20.New(c.contentKey, nonce)
+	binary.BigEndian.PutUint32(nonce[8:], seqNum)
-	var polyKey [32]byte
+	s, err := chacha20.NewUnauthenticatedCipher(c.contentKey[:], nonce)
+	if err != nil {
+		return err
+	}
+	var polyKey, discardBuf [32]byte
 	s.XORKeyStream(polyKey[:], polyKey[:])
-	s.Advance() // skip next 32 bytes
+	s.XORKeyStream(discardBuf[:], discardBuf[:]) // skip the next 32 bytes
 
 	// There is no blocksize, so fall back to multiple of 8 byte
 	// padding, as described in RFC 4253, Sec 6.
@@ -748,7 +755,11 @@ func (c *chacha20Poly1305Cipher) writeCipherPacket(seqNum uint32, w io.Writer, r
 	}
 
 	binary.BigEndian.PutUint32(c.buf, uint32(1+len(payload)+padding))
-	chacha20.New(c.lengthKey, nonce).XORKeyStream(c.buf, c.buf[:4])
+	ls, err := chacha20.NewUnauthenticatedCipher(c.lengthKey[:], nonce)
+	if err != nil {
+		return err
+	}
+	ls.XORKeyStream(c.buf, c.buf[:4])
 	c.buf[4] = byte(padding)
 	copy(c.buf[5:], payload)
 	packetEnd := 5 + len(payload) + padding

vendor/golang.org/x/crypto/ssh/client_auth.go

@@ -523,3 +523,117 @@ func (r *retryableAuthMethod) method() string {
 func RetryableAuthMethod(auth AuthMethod, maxTries int) AuthMethod {
 	return &retryableAuthMethod{authMethod: auth, maxTries: maxTries}
 }
+
+// GSSAPIWithMICAuthMethod is an AuthMethod with "gssapi-with-mic" authentication.
+// See RFC 4462 section 3
+// gssAPIClient is implementation of the GSSAPIClient interface, see the definition of the interface for details.
+// target is the server host you want to log in to.
+func GSSAPIWithMICAuthMethod(gssAPIClient GSSAPIClient, target string) AuthMethod {
+	if gssAPIClient == nil {
+		panic("gss-api client must be not nil with enable gssapi-with-mic")
+	}
+	return &gssAPIWithMICCallback{gssAPIClient: gssAPIClient, target: target}
+}
+
+type gssAPIWithMICCallback struct {
+	gssAPIClient GSSAPIClient
+	target       string
+}
+
+func (g *gssAPIWithMICCallback) auth(session []byte, user string, c packetConn, rand io.Reader) (authResult, []string, error) {
+	m := &userAuthRequestMsg{
+		User:    user,
+		Service: serviceSSH,
+		Method:  g.method(),
+	}
+	// The GSS-API authentication method is initiated when the client sends an SSH_MSG_USERAUTH_REQUEST.
+	// See RFC 4462 section 3.2.
+	m.Payload = appendU32(m.Payload, 1)
+	m.Payload = appendString(m.Payload, string(krb5OID))
+	if err := c.writePacket(Marshal(m)); err != nil {
+		return authFailure, nil, err
+	}
+	// The server responds to the SSH_MSG_USERAUTH_REQUEST with either an
+	// SSH_MSG_USERAUTH_FAILURE if none of the mechanisms are supported or
+	// with an SSH_MSG_USERAUTH_GSSAPI_RESPONSE.
+	// See RFC 4462 section 3.3.
+	// OpenSSH supports Kerberos V5 mechanism only for GSS-API authentication,so I don't want to check
+	// selected mech if it is valid.
+	packet, err := c.readPacket()
+	if err != nil {
+		return authFailure, nil, err
+	}
+	userAuthGSSAPIResp := &userAuthGSSAPIResponse{}
+	if err := Unmarshal(packet, userAuthGSSAPIResp); err != nil {
+		return authFailure, nil, err
+	}
+	// Start the loop into the exchange token.
+	// See RFC 4462 section 3.4.
+	var token []byte
+	defer g.gssAPIClient.DeleteSecContext()
+	for {
+		// Initiates the establishment of a security context between the application and a remote peer.
+		nextToken, needContinue, err := g.gssAPIClient.InitSecContext("host@"+g.target, token, false)
+		if err != nil {
+			return authFailure, nil, err
+		}
+		if len(nextToken) > 0 {
+			if err := c.writePacket(Marshal(&userAuthGSSAPIToken{
+				Token: nextToken,
+			})); err != nil {
+				return authFailure, nil, err
+			}
+		}
+		if !needContinue {
+			break
+		}
+		packet, err = c.readPacket()
+		if err != nil {
+			return authFailure, nil, err
+		}
+		switch packet[0] {
+		case msgUserAuthFailure:
+			var msg userAuthFailureMsg
+			if err := Unmarshal(packet, &msg); err != nil {
+				return authFailure, nil, err
+			}
+			if msg.PartialSuccess {
+				return authPartialSuccess, msg.Methods, nil
+			}
+			return authFailure, msg.Methods, nil
+		case msgUserAuthGSSAPIError:
+			userAuthGSSAPIErrorResp := &userAuthGSSAPIError{}
+			if err := Unmarshal(packet, userAuthGSSAPIErrorResp); err != nil {
+				return authFailure, nil, err
+			}
+			return authFailure, nil, fmt.Errorf("GSS-API Error:\n"+
+				"Major Status: %d\n"+
+				"Minor Status: %d\n"+
+				"Error Message: %s\n", userAuthGSSAPIErrorResp.MajorStatus, userAuthGSSAPIErrorResp.MinorStatus,
+				userAuthGSSAPIErrorResp.Message)
+		case msgUserAuthGSSAPIToken:
+			userAuthGSSAPITokenReq := &userAuthGSSAPIToken{}
+			if err := Unmarshal(packet, userAuthGSSAPITokenReq); err != nil {
+				return authFailure, nil, err
+			}
+			token = userAuthGSSAPITokenReq.Token
+		}
+	}
+	// Binding Encryption Keys.
+	// See RFC 4462 section 3.5.
+	micField := buildMIC(string(session), user, "ssh-connection", "gssapi-with-mic")
+	micToken, err := g.gssAPIClient.GetMIC(micField)
+	if err != nil {
+		return authFailure, nil, err
+	}
+	if err := c.writePacket(Marshal(&userAuthGSSAPIMIC{
+		MIC: micToken,
+	})); err != nil {
+		return authFailure, nil, err
+	}
+	return handleAuthResponse(c)
+}
+
+func (g *gssAPIWithMICCallback) method() string {
+	return "gssapi-with-mic"
+}

vendor/golang.org/x/crypto/ssh/common.go

@@ -51,6 +51,21 @@ var supportedKexAlgos = []string{
 	kexAlgoDH14SHA1, kexAlgoDH1SHA1,
 }
 
+// serverForbiddenKexAlgos contains key exchange algorithms, that are forbidden
+// for the server half.
+var serverForbiddenKexAlgos = map[string]struct{}{
+	kexAlgoDHGEXSHA1:   {}, // server half implementation is only minimal to satisfy the automated tests
+	kexAlgoDHGEXSHA256: {}, // server half implementation is only minimal to satisfy the automated tests
+}
+
+// preferredKexAlgos specifies the default preference for key-exchange algorithms
+// in preference order.
+var preferredKexAlgos = []string{
+	kexAlgoCurve25519SHA256,
+	kexAlgoECDH256, kexAlgoECDH384, kexAlgoECDH521,
+	kexAlgoDH14SHA1,
+}
+
 // supportedHostKeyAlgos specifies the supported host-key algorithms (i.e. methods
 // of authenticating servers) in preference order.
 var supportedHostKeyAlgos = []string{
@@ -109,6 +124,7 @@ func findCommon(what string, client []string, server []string) (common string, e
 	return "", fmt.Errorf("ssh: no common algorithm for %s; client offered: %v, server offered: %v", what, client, server)
 }
 
+// directionAlgorithms records algorithm choices in one direction (either read or write)
 type directionAlgorithms struct {
 	Cipher      string
 	MAC         string
@@ -137,7 +153,7 @@ type algorithms struct {
 	r       directionAlgorithms
 }
 
-func findAgreedAlgorithms(clientKexInit, serverKexInit *kexInitMsg) (algs *algorithms, err error) {
+func findAgreedAlgorithms(isClient bool, clientKexInit, serverKexInit *kexInitMsg) (algs *algorithms, err error) {
 	result := &algorithms{}
 
 	result.kex, err = findCommon("key exchange", clientKexInit.KexAlgos, serverKexInit.KexAlgos)
@@ -150,32 +166,37 @@ func findAgreedAlgorithms(clientKexInit, serverKexInit *kexInitMsg) (algs *algor
 		return
 	}
 
-	result.w.Cipher, err = findCommon("client to server cipher", clientKexInit.CiphersClientServer, serverKexInit.CiphersClientServer)
+	stoc, ctos := &result.w, &result.r
+	if isClient {
+		ctos, stoc = stoc, ctos
+	}
+
+	ctos.Cipher, err = findCommon("client to server cipher", clientKexInit.CiphersClientServer, serverKexInit.CiphersClientServer)
 	if err != nil {
 		return
 	}
 
-	result.r.Cipher, err = findCommon("server to client cipher", clientKexInit.CiphersServerClient, serverKexInit.CiphersServerClient)
+	stoc.Cipher, err = findCommon("server to client cipher", clientKexInit.CiphersServerClient, serverKexInit.CiphersServerClient)
 	if err != nil {
 		return
 	}
 
-	result.w.MAC, err = findCommon("client to server MAC", clientKexInit.MACsClientServer, serverKexInit.MACsClientServer)
+	ctos.MAC, err = findCommon("client to server MAC", clientKexInit.MACsClientServer, serverKexInit.MACsClientServer)
 	if err != nil {
 		return
 	}
 
-	result.r.MAC, err = findCommon("server to client MAC", clientKexInit.MACsServerClient, serverKexInit.MACsServerClient)
+	stoc.MAC, err = findCommon("server to client MAC", clientKexInit.MACsServerClient, serverKexInit.MACsServerClient)
 	if err != nil {
 		return
 	}
 
-	result.w.Compression, err = findCommon("client to server compression", clientKexInit.CompressionClientServer, serverKexInit.CompressionClientServer)
+	ctos.Compression, err = findCommon("client to server compression", clientKexInit.CompressionClientServer, serverKexInit.CompressionClientServer)
 	if err != nil {
 		return
 	}
 
-	result.r.Compression, err = findCommon("server to client compression", clientKexInit.CompressionServerClient, serverKexInit.CompressionServerClient)
+	stoc.Compression, err = findCommon("server to client compression", clientKexInit.CompressionServerClient, serverKexInit.CompressionServerClient)
 	if err != nil {
 		return
 	}
@@ -233,7 +254,7 @@ func (c *Config) SetDefaults() {
 	c.Ciphers = ciphers
 
 	if c.KeyExchanges == nil {
-		c.KeyExchanges = supportedKexAlgos
+		c.KeyExchanges = preferredKexAlgos
 	}
 
 	if c.MACs == nil {

vendor/golang.org/x/crypto/ssh/handshake.go

@@ -543,7 +543,8 @@ func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error {
 
 	clientInit := otherInit
 	serverInit := t.sentInitMsg
-	if len(t.hostKeys) == 0 {
+	isClient := len(t.hostKeys) == 0
+	if isClient {
 		clientInit, serverInit = serverInit, clientInit
 
 		magics.clientKexInit = t.sentInitPacket
@@ -551,7 +552,7 @@ func (t *handshakeTransport) enterKeyExchange(otherInitPacket []byte) error {
 	}
 
 	var err error
-	t.algorithms, err = findAgreedAlgorithms(clientInit, serverInit)
+	t.algorithms, err = findAgreedAlgorithms(isClient, clientInit, serverInit)
 	if err != nil {
 		return err
 	}

vendor/golang.org/x/crypto/ssh/kex.go

@@ -10,7 +10,9 @@ import (
 	"crypto/elliptic"
 	"crypto/rand"
 	"crypto/subtle"
+	"encoding/binary"
 	"errors"
+	"fmt"
 	"io"
 	"math/big"
 
@@ -24,6 +26,12 @@ const (
 	kexAlgoECDH384          = "ecdh-sha2-nistp384"
 	kexAlgoECDH521          = "ecdh-sha2-nistp521"
 	kexAlgoCurve25519SHA256 = "curve25519-sha256@libssh.org"
+
+	// For the following kex only the client half contains a production
+	// ready implementation. The server half only consists of a minimal
+	// implementation to satisfy the automated tests.
+	kexAlgoDHGEXSHA1   = "diffie-hellman-group-exchange-sha1"
+	kexAlgoDHGEXSHA256 = "diffie-hellman-group-exchange-sha256"
 )
 
 // kexResult captures the outcome of a key exchange.
@@ -204,7 +212,7 @@ func (group *dhGroup) Server(c packetConn, randSource io.Reader, magics *handsha
 		HostKey:   hostKeyBytes,
 		Signature: sig,
 		Hash:      crypto.SHA1,
-	}, nil
+	}, err
 }
 
 // ecdh performs Elliptic Curve Diffie-Hellman key exchange as
@@ -402,6 +410,8 @@ func init() {
 	kexAlgoMap[kexAlgoECDH384] = &ecdh{elliptic.P384()}
 	kexAlgoMap[kexAlgoECDH256] = &ecdh{elliptic.P256()}
 	kexAlgoMap[kexAlgoCurve25519SHA256] = &curve25519sha256{}
+	kexAlgoMap[kexAlgoDHGEXSHA1] = &dhGEXSHA{hashFunc: crypto.SHA1}
+	kexAlgoMap[kexAlgoDHGEXSHA256] = &dhGEXSHA{hashFunc: crypto.SHA256}
 }
 
 // curve25519sha256 implements the curve25519-sha256@libssh.org key
@@ -538,3 +548,242 @@ func (kex *curve25519sha256) Server(c packetConn, rand io.Reader, magics *handsh
 		Hash:      crypto.SHA256,
 	}, nil
 }
+
+// dhGEXSHA implements the diffie-hellman-group-exchange-sha1 and
+// diffie-hellman-group-exchange-sha256 key agreement protocols,
+// as described in RFC 4419
+type dhGEXSHA struct {
+	g, p     *big.Int
+	hashFunc crypto.Hash
+}
+
+const numMRTests = 64
+
+const (
+	dhGroupExchangeMinimumBits   = 2048
+	dhGroupExchangePreferredBits = 2048
+	dhGroupExchangeMaximumBits   = 8192
+)
+
+func (gex *dhGEXSHA) diffieHellman(theirPublic, myPrivate *big.Int) (*big.Int, error) {
+	if theirPublic.Sign() <= 0 || theirPublic.Cmp(gex.p) >= 0 {
+		return nil, fmt.Errorf("ssh: DH parameter out of bounds")
+	}
+	return new(big.Int).Exp(theirPublic, myPrivate, gex.p), nil
+}
+
+func (gex *dhGEXSHA) Client(c packetConn, randSource io.Reader, magics *handshakeMagics) (*kexResult, error) {
+	// Send GexRequest
+	kexDHGexRequest := kexDHGexRequestMsg{
+		MinBits:      dhGroupExchangeMinimumBits,
+		PreferedBits: dhGroupExchangePreferredBits,
+		MaxBits:      dhGroupExchangeMaximumBits,
+	}
+	if err := c.writePacket(Marshal(&kexDHGexRequest)); err != nil {
+		return nil, err
+	}
+
+	// Receive GexGroup
+	packet, err := c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var kexDHGexGroup kexDHGexGroupMsg
+	if err = Unmarshal(packet, &kexDHGexGroup); err != nil {
+		return nil, err
+	}
+
+	// reject if p's bit length < dhGroupExchangeMinimumBits or > dhGroupExchangeMaximumBits
+	if kexDHGexGroup.P.BitLen() < dhGroupExchangeMinimumBits || kexDHGexGroup.P.BitLen() > dhGroupExchangeMaximumBits {
+		return nil, fmt.Errorf("ssh: server-generated gex p is out of range (%d bits)", kexDHGexGroup.P.BitLen())
+	}
+
+	gex.p = kexDHGexGroup.P
+	gex.g = kexDHGexGroup.G
+
+	// Check if p is safe by verifing that p and (p-1)/2 are primes
+	one := big.NewInt(1)
+	var pHalf = &big.Int{}
+	pHalf.Rsh(gex.p, 1)
+	if !gex.p.ProbablyPrime(numMRTests) || !pHalf.ProbablyPrime(numMRTests) {
+		return nil, fmt.Errorf("ssh: server provided gex p is not safe")
+	}
+
+	// Check if g is safe by verifing that g > 1 and g < p - 1
+	var pMinusOne = &big.Int{}
+	pMinusOne.Sub(gex.p, one)
+	if gex.g.Cmp(one) != 1 && gex.g.Cmp(pMinusOne) != -1 {
+		return nil, fmt.Errorf("ssh: server provided gex g is not safe")
+	}
+
+	// Send GexInit
+	x, err := rand.Int(randSource, pHalf)
+	if err != nil {
+		return nil, err
+	}
+	X := new(big.Int).Exp(gex.g, x, gex.p)
+	kexDHGexInit := kexDHGexInitMsg{
+		X: X,
+	}
+	if err := c.writePacket(Marshal(&kexDHGexInit)); err != nil {
+		return nil, err
+	}
+
+	// Receive GexReply
+	packet, err = c.readPacket()
+	if err != nil {
+		return nil, err
+	}
+
+	var kexDHGexReply kexDHGexReplyMsg
+	if err = Unmarshal(packet, &kexDHGexReply); err != nil {
+		return nil, err
+	}
+
+	kInt, err := gex.diffieHellman(kexDHGexReply.Y, x)
+	if err != nil {
+		return nil, err
+	}
+
+	// Check if k is safe by verifing that k > 1 and k < p - 1
+	if kInt.Cmp(one) != 1 && kInt.Cmp(pMinusOne) != -1 {
+		return nil, fmt.Errorf("ssh: derived k is not safe")
+	}
+
+	h := gex.hashFunc.New()
+	magics.write(h)
+	writeString(h, kexDHGexReply.HostKey)
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMinimumBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangePreferredBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMaximumBits))
+	writeInt(h, gex.p)
+	writeInt(h, gex.g)
+	writeInt(h, X)
+	writeInt(h, kexDHGexReply.Y)
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	return &kexResult{
+		H:         h.Sum(nil),
+		K:         K,
+		HostKey:   kexDHGexReply.HostKey,
+		Signature: kexDHGexReply.Signature,
+		Hash:      gex.hashFunc,
+	}, nil
+}
+
+// Server half implementation of the Diffie Hellman Key Exchange with SHA1 and SHA256.
+//
+// This is a minimal implementation to satisfy the automated tests.
+func (gex *dhGEXSHA) Server(c packetConn, randSource io.Reader, magics *handshakeMagics, priv Signer) (result *kexResult, err error) {
+	// Receive GexRequest
+	packet, err := c.readPacket()
+	if err != nil {
+		return
+	}
+	var kexDHGexRequest kexDHGexRequestMsg
+	if err = Unmarshal(packet, &kexDHGexRequest); err != nil {
+		return
+	}
+
+	// smoosh the user's preferred size into our own limits
+	if kexDHGexRequest.PreferedBits > dhGroupExchangeMaximumBits {
+		kexDHGexRequest.PreferedBits = dhGroupExchangeMaximumBits
+	}
+	if kexDHGexRequest.PreferedBits < dhGroupExchangeMinimumBits {
+		kexDHGexRequest.PreferedBits = dhGroupExchangeMinimumBits
+	}
+	// fix min/max if they're inconsistent.  technically, we could just pout
+	// and hang up, but there's no harm in giving them the benefit of the
+	// doubt and just picking a bitsize for them.
+	if kexDHGexRequest.MinBits > kexDHGexRequest.PreferedBits {
+		kexDHGexRequest.MinBits = kexDHGexRequest.PreferedBits
+	}
+	if kexDHGexRequest.MaxBits < kexDHGexRequest.PreferedBits {
+		kexDHGexRequest.MaxBits = kexDHGexRequest.PreferedBits
+	}
+
+	// Send GexGroup
+	// This is the group called diffie-hellman-group14-sha1 in RFC
+	// 4253 and Oakley Group 14 in RFC 3526.
+	p, _ := new(big.Int).SetString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
+	gex.p = p
+	gex.g = big.NewInt(2)
+
+	kexDHGexGroup := kexDHGexGroupMsg{
+		P: gex.p,
+		G: gex.g,
+	}
+	if err := c.writePacket(Marshal(&kexDHGexGroup)); err != nil {
+		return nil, err
+	}
+
+	// Receive GexInit
+	packet, err = c.readPacket()
+	if err != nil {
+		return
+	}
+	var kexDHGexInit kexDHGexInitMsg
+	if err = Unmarshal(packet, &kexDHGexInit); err != nil {
+		return
+	}
+
+	var pHalf = &big.Int{}
+	pHalf.Rsh(gex.p, 1)
+
+	y, err := rand.Int(randSource, pHalf)
+	if err != nil {
+		return
+	}
+
+	Y := new(big.Int).Exp(gex.g, y, gex.p)
+	kInt, err := gex.diffieHellman(kexDHGexInit.X, y)
+	if err != nil {
+		return nil, err
+	}
+
+	hostKeyBytes := priv.PublicKey().Marshal()
+
+	h := gex.hashFunc.New()
+	magics.write(h)
+	writeString(h, hostKeyBytes)
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMinimumBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangePreferredBits))
+	binary.Write(h, binary.BigEndian, uint32(dhGroupExchangeMaximumBits))
+	writeInt(h, gex.p)
+	writeInt(h, gex.g)
+	writeInt(h, kexDHGexInit.X)
+	writeInt(h, Y)
+
+	K := make([]byte, intLength(kInt))
+	marshalInt(K, kInt)
+	h.Write(K)
+
+	H := h.Sum(nil)
+
+	// H is already a hash, but the hostkey signing will apply its
+	// own key-specific hash algorithm.
+	sig, err := signAndMarshal(priv, randSource, H)
+	if err != nil {
+		return nil, err
+	}
+
+	kexDHGexReply := kexDHGexReplyMsg{
+		HostKey:   hostKeyBytes,
+		Y:         Y,
+		Signature: sig,
+	}
+	packet = Marshal(&kexDHGexReply)
+
+	err = c.writePacket(packet)
+
+	return &kexResult{
+		H:         H,
+		K:         K,
+		HostKey:   hostKeyBytes,
+		Signature: sig,
+		Hash:      gex.hashFunc,
+	}, err
+}

vendor/golang.org/x/crypto/ssh/keys.go

@@ -30,12 +30,14 @@ import (
 // These constants represent the algorithm names for key types supported by this
 // package.
 const (
-	KeyAlgoRSA      = "ssh-rsa"
+	KeyAlgoRSA        = "ssh-rsa"
-	KeyAlgoDSA      = "ssh-dss"
+	KeyAlgoDSA        = "ssh-dss"
-	KeyAlgoECDSA256 = "ecdsa-sha2-nistp256"
+	KeyAlgoECDSA256   = "ecdsa-sha2-nistp256"
-	KeyAlgoECDSA384 = "ecdsa-sha2-nistp384"
+	KeyAlgoSKECDSA256 = "sk-ecdsa-sha2-nistp256@openssh.com"
-	KeyAlgoECDSA521 = "ecdsa-sha2-nistp521"
+	KeyAlgoECDSA384   = "ecdsa-sha2-nistp384"
-	KeyAlgoED25519  = "ssh-ed25519"
+	KeyAlgoECDSA521   = "ecdsa-sha2-nistp521"
+	KeyAlgoED25519    = "ssh-ed25519"
+	KeyAlgoSKED25519  = "sk-ssh-ed25519@openssh.com"
 )
 
 // These constants represent non-default signature algorithms that are supported
@@ -58,9 +60,13 @@ func parsePubKey(in []byte, algo string) (pubKey PublicKey, rest []byte, err err
 		return parseDSA(in)
 	case KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521:
 		return parseECDSA(in)
+	case KeyAlgoSKECDSA256:
+		return parseSKECDSA(in)
 	case KeyAlgoED25519:
 		return parseED25519(in)
-	case CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01:
+	case KeyAlgoSKED25519:
+		return parseSKEd25519(in)
+	case CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoSKECDSA256v01, CertAlgoED25519v01, CertAlgoSKED25519v01:
 		cert, err := parseCert(in, certToPrivAlgo(algo))
 		if err != nil {
 			return nil, nil, err
@@ -685,6 +691,218 @@ func (k *ecdsaPublicKey) CryptoPublicKey() crypto.PublicKey {
 	return (*ecdsa.PublicKey)(k)
 }
 
+// skFields holds the additional fields present in U2F/FIDO2 signatures.
+// See openssh/PROTOCOL.u2f 'SSH U2F Signatures' for details.
+type skFields struct {
+	// Flags contains U2F/FIDO2 flags such as 'user present'
+	Flags byte
+	// Counter is a monotonic signature counter which can be
+	// used to detect concurrent use of a private key, should
+	// it be extracted from hardware.
+	Counter uint32
+}
+
+type skECDSAPublicKey struct {
+	// application is a URL-like string, typically "ssh:" for SSH.
+	// see openssh/PROTOCOL.u2f for details.
+	application string
+	ecdsa.PublicKey
+}
+
+func (k *skECDSAPublicKey) Type() string {
+	return KeyAlgoSKECDSA256
+}
+
+func (k *skECDSAPublicKey) nistID() string {
+	return "nistp256"
+}
+
+func parseSKECDSA(in []byte) (out PublicKey, rest []byte, err error) {
+	var w struct {
+		Curve       string
+		KeyBytes    []byte
+		Application string
+		Rest        []byte `ssh:"rest"`
+	}
+
+	if err := Unmarshal(in, &w); err != nil {
+		return nil, nil, err
+	}
+
+	key := new(skECDSAPublicKey)
+	key.application = w.Application
+
+	if w.Curve != "nistp256" {
+		return nil, nil, errors.New("ssh: unsupported curve")
+	}
+	key.Curve = elliptic.P256()
+
+	key.X, key.Y = elliptic.Unmarshal(key.Curve, w.KeyBytes)
+	if key.X == nil || key.Y == nil {
+		return nil, nil, errors.New("ssh: invalid curve point")
+	}
+
+	return key, w.Rest, nil
+}
+
+func (k *skECDSAPublicKey) Marshal() []byte {
+	// See RFC 5656, section 3.1.
+	keyBytes := elliptic.Marshal(k.Curve, k.X, k.Y)
+	w := struct {
+		Name        string
+		ID          string
+		Key         []byte
+		Application string
+	}{
+		k.Type(),
+		k.nistID(),
+		keyBytes,
+		k.application,
+	}
+
+	return Marshal(&w)
+}
+
+func (k *skECDSAPublicKey) Verify(data []byte, sig *Signature) error {
+	if sig.Format != k.Type() {
+		return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, k.Type())
+	}
+
+	h := ecHash(k.Curve).New()
+	h.Write([]byte(k.application))
+	appDigest := h.Sum(nil)
+
+	h.Reset()
+	h.Write(data)
+	dataDigest := h.Sum(nil)
+
+	var ecSig struct {
+		R *big.Int
+		S *big.Int
+	}
+	if err := Unmarshal(sig.Blob, &ecSig); err != nil {
+		return err
+	}
+
+	var skf skFields
+	if err := Unmarshal(sig.Rest, &skf); err != nil {
+		return err
+	}
+
+	blob := struct {
+		ApplicationDigest []byte `ssh:"rest"`
+		Flags             byte
+		Counter           uint32
+		MessageDigest     []byte `ssh:"rest"`
+	}{
+		appDigest,
+		skf.Flags,
+		skf.Counter,
+		dataDigest,
+	}
+
+	original := Marshal(blob)
+
+	h.Reset()
+	h.Write(original)
+	digest := h.Sum(nil)
+
+	if ecdsa.Verify((*ecdsa.PublicKey)(&k.PublicKey), digest, ecSig.R, ecSig.S) {
+		return nil
+	}
+	return errors.New("ssh: signature did not verify")
+}
+
+type skEd25519PublicKey struct {
+	// application is a URL-like string, typically "ssh:" for SSH.
+	// see openssh/PROTOCOL.u2f for details.
+	application string
+	ed25519.PublicKey
+}
+
+func (k *skEd25519PublicKey) Type() string {
+	return KeyAlgoSKED25519
+}
+
+func parseSKEd25519(in []byte) (out PublicKey, rest []byte, err error) {
+	var w struct {
+		KeyBytes    []byte
+		Application string
+		Rest        []byte `ssh:"rest"`
+	}
+
+	if err := Unmarshal(in, &w); err != nil {
+		return nil, nil, err
+	}
+
+	key := new(skEd25519PublicKey)
+	key.application = w.Application
+	key.PublicKey = ed25519.PublicKey(w.KeyBytes)
+
+	return key, w.Rest, nil
+}
+
+func (k *skEd25519PublicKey) Marshal() []byte {
+	w := struct {
+		Name        string
+		KeyBytes    []byte
+		Application string
+	}{
+		KeyAlgoSKED25519,
+		[]byte(k.PublicKey),
+		k.application,
+	}
+	return Marshal(&w)
+}
+
+func (k *skEd25519PublicKey) Verify(data []byte, sig *Signature) error {
+	if sig.Format != k.Type() {
+		return fmt.Errorf("ssh: signature type %s for key type %s", sig.Format, k.Type())
+	}
+
+	h := sha256.New()
+	h.Write([]byte(k.application))
+	appDigest := h.Sum(nil)
+
+	h.Reset()
+	h.Write(data)
+	dataDigest := h.Sum(nil)
+
+	var edSig struct {
+		Signature []byte `ssh:"rest"`
+	}
+
+	if err := Unmarshal(sig.Blob, &edSig); err != nil {
+		return err
+	}
+
+	var skf skFields
+	if err := Unmarshal(sig.Rest, &skf); err != nil {
+		return err
+	}
+
+	blob := struct {
+		ApplicationDigest []byte `ssh:"rest"`
+		Flags             byte
+		Counter           uint32
+		MessageDigest     []byte `ssh:"rest"`
+	}{
+		appDigest,
+		skf.Flags,
+		skf.Counter,
+		dataDigest,
+	}
+
+	original := Marshal(blob)
+
+	edKey := (ed25519.PublicKey)(k.PublicKey)
+	if ok := ed25519.Verify(edKey, original, edSig.Signature); !ok {
+		return errors.New("ssh: signature did not verify")
+	}
+
+	return nil
+}
+
 // NewSignerFromKey takes an *rsa.PrivateKey, *dsa.PrivateKey,
 // *ecdsa.PrivateKey or any other crypto.Signer and returns a
 // corresponding Signer instance. ECDSA keys must use P-256, P-384 or
@@ -837,7 +1055,8 @@ func NewPublicKey(key interface{}) (PublicKey, error) {
 }
 
 // ParsePrivateKey returns a Signer from a PEM encoded private key. It supports
-// the same keys as ParseRawPrivateKey.
+// the same keys as ParseRawPrivateKey. If the private key is encrypted, it
+// will return a PassphraseMissingError.
 func ParsePrivateKey(pemBytes []byte) (Signer, error) {
 	key, err := ParseRawPrivateKey(pemBytes)
 	if err != nil {
@@ -850,8 +1069,8 @@ func ParsePrivateKey(pemBytes []byte) (Signer, error) {
 // ParsePrivateKeyWithPassphrase returns a Signer from a PEM encoded private
 // key and passphrase. It supports the same keys as
 // ParseRawPrivateKeyWithPassphrase.
-func ParsePrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (Signer, error) {
+func ParsePrivateKeyWithPassphrase(pemBytes, passphrase []byte) (Signer, error) {
-	key, err := ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase)
+	key, err := ParseRawPrivateKeyWithPassphrase(pemBytes, passphrase)
 	if err != nil {
 		return nil, err
 	}
@@ -867,8 +1086,21 @@ func encryptedBlock(block *pem.Block) bool {
 	return strings.Contains(block.Headers["Proc-Type"], "ENCRYPTED")
 }
 
+// A PassphraseMissingError indicates that parsing this private key requires a
+// passphrase. Use ParsePrivateKeyWithPassphrase.
+type PassphraseMissingError struct {
+	// PublicKey will be set if the private key format includes an unencrypted
+	// public key along with the encrypted private key.
+	PublicKey PublicKey
+}
+
+func (*PassphraseMissingError) Error() string {
+	return "ssh: this private key is passphrase protected"
+}
+
 // ParseRawPrivateKey returns a private key from a PEM encoded private key. It
-// supports RSA (PKCS#1), PKCS#8, DSA (OpenSSL), and ECDSA private keys.
+// supports RSA (PKCS#1), PKCS#8, DSA (OpenSSL), and ECDSA private keys. If the
+// private key is encrypted, it will return a PassphraseMissingError.
 func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
 	block, _ := pem.Decode(pemBytes)
 	if block == nil {
@@ -876,7 +1108,7 @@ func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
 	}
 
 	if encryptedBlock(block) {
-		return nil, errors.New("ssh: cannot decode encrypted private keys")
+		return nil, &PassphraseMissingError{}
 	}
 
 	switch block.Type {
@@ -899,24 +1131,22 @@ func ParseRawPrivateKey(pemBytes []byte) (interface{}, error) {
 // ParseRawPrivateKeyWithPassphrase returns a private key decrypted with
 // passphrase from a PEM encoded private key. If wrong passphrase, return
 // x509.IncorrectPasswordError.
-func ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (interface{}, error) {
+func ParseRawPrivateKeyWithPassphrase(pemBytes, passphrase []byte) (interface{}, error) {
 	block, _ := pem.Decode(pemBytes)
 	if block == nil {
 		return nil, errors.New("ssh: no key found")
 	}
-	buf := block.Bytes
 
-	if encryptedBlock(block) {
+	if !encryptedBlock(block) || !x509.IsEncryptedPEMBlock(block) {
-		if x509.IsEncryptedPEMBlock(block) {
+		return nil, errors.New("ssh: not an encrypted key")
-			var err error
+	}
-			buf, err = x509.DecryptPEMBlock(block, passPhrase)
+
-			if err != nil {
+	buf, err := x509.DecryptPEMBlock(block, passphrase)
-				if err == x509.IncorrectPasswordError {
+	if err != nil {
-					return nil, err
+		if err == x509.IncorrectPasswordError {
-				}
+			return nil, err
-				return nil, fmt.Errorf("ssh: cannot decode encrypted private keys: %v", err)
-			}
 		}
+		return nil, fmt.Errorf("ssh: cannot decode encrypted private keys: %v", err)
 	}
 
 	switch block.Type {
@@ -926,8 +1156,6 @@ func ParseRawPrivateKeyWithPassphrase(pemBytes, passPhrase []byte) (interface{},
 		return x509.ParseECPrivateKey(buf)
 	case "DSA PRIVATE KEY":
 		return ParseDSAPrivateKey(buf)
-	case "OPENSSH PRIVATE KEY":
-		return parseOpenSSHPrivateKey(buf)
 	default:
 		return nil, fmt.Errorf("ssh: unsupported key type %q", block.Type)
 	}

vendor/golang.org/x/crypto/ssh/messages.go

@@ -97,6 +97,36 @@ type kexDHReplyMsg struct {
 	Signature []byte
 }
 
+// See RFC 4419, section 5.
+const msgKexDHGexGroup = 31
+
+type kexDHGexGroupMsg struct {
+	P *big.Int `sshtype:"31"`
+	G *big.Int
+}
+
+const msgKexDHGexInit = 32
+
+type kexDHGexInitMsg struct {
+	X *big.Int `sshtype:"32"`
+}
+
+const msgKexDHGexReply = 33
+
+type kexDHGexReplyMsg struct {
+	HostKey   []byte `sshtype:"33"`
+	Y         *big.Int
+	Signature []byte
+}
+
+const msgKexDHGexRequest = 34
+
+type kexDHGexRequestMsg struct {
+	MinBits      uint32 `sshtype:"34"`
+	PreferedBits uint32
+	MaxBits      uint32
+}
+
 // See RFC 4253, section 10.
 const msgServiceRequest = 5
 
@@ -275,6 +305,42 @@ type userAuthPubKeyOkMsg struct {
 	PubKey []byte
 }
 
+// See RFC 4462, section 3
+const msgUserAuthGSSAPIResponse = 60
+
+type userAuthGSSAPIResponse struct {
+	SupportMech []byte `sshtype:"60"`
+}
+
+const msgUserAuthGSSAPIToken = 61
+
+type userAuthGSSAPIToken struct {
+	Token []byte `sshtype:"61"`
+}
+
+const msgUserAuthGSSAPIMIC = 66
+
+type userAuthGSSAPIMIC struct {
+	MIC []byte `sshtype:"66"`
+}
+
+// See RFC 4462, section 3.9
+const msgUserAuthGSSAPIErrTok = 64
+
+type userAuthGSSAPIErrTok struct {
+	ErrorToken []byte `sshtype:"64"`
+}
+
+// See RFC 4462, section 3.8
+const msgUserAuthGSSAPIError = 65
+
+type userAuthGSSAPIError struct {
+	MajorStatus uint32 `sshtype:"65"`
+	MinorStatus uint32
+	Message     string
+	LanguageTag string
+}
+
 // typeTags returns the possible type bytes for the given reflect.Type, which
 // should be a struct. The possible values are separated by a '|' character.
 func typeTags(structType reflect.Type) (tags []byte) {
@@ -756,6 +822,14 @@ func decode(packet []byte) (interface{}, error) {
 		msg = new(channelRequestSuccessMsg)
 	case msgChannelFailure:
 		msg = new(channelRequestFailureMsg)
+	case msgUserAuthGSSAPIToken:
+		msg = new(userAuthGSSAPIToken)
+	case msgUserAuthGSSAPIMIC:
+		msg = new(userAuthGSSAPIMIC)
+	case msgUserAuthGSSAPIErrTok:
+		msg = new(userAuthGSSAPIErrTok)
+	case msgUserAuthGSSAPIError:
+		msg = new(userAuthGSSAPIError)
 	default:
 		return nil, unexpectedMessageError(0, packet[0])
 	}

vendor/golang.org/x/crypto/ssh/server.go

@@ -45,6 +45,20 @@ type Permissions struct {
 	Extensions map[string]string
 }
 
+type GSSAPIWithMICConfig struct {
+	// AllowLogin, must be set, is called when gssapi-with-mic
+	// authentication is selected (RFC 4462 section 3). The srcName is from the
+	// results of the GSS-API authentication. The format is username@DOMAIN.
+	// GSSAPI just guarantees to the server who the user is, but not if they can log in, and with what permissions.
+	// This callback is called after the user identity is established with GSSAPI to decide if the user can login with
+	// which permissions. If the user is allowed to login, it should return a nil error.
+	AllowLogin func(conn ConnMetadata, srcName string) (*Permissions, error)
+
+	// Server must be set. It's the implementation
+	// of the GSSAPIServer interface. See GSSAPIServer interface for details.
+	Server GSSAPIServer
+}
+
 // ServerConfig holds server specific configuration data.
 type ServerConfig struct {
 	// Config contains configuration shared between client and server.
@@ -99,6 +113,10 @@ type ServerConfig struct {
 	// BannerCallback, if present, is called and the return string is sent to
 	// the client after key exchange completed but before authentication.
 	BannerCallback func(conn ConnMetadata) string
+
+	// GSSAPIWithMICConfig includes gssapi server and callback, which if both non-nil, is used
+	// when gssapi-with-mic authentication is selected (RFC 4462 section 3).
+	GSSAPIWithMICConfig *GSSAPIWithMICConfig
 }
 
 // AddHostKey adds a private key as a host key. If an existing host
@@ -175,6 +193,12 @@ func NewServerConn(c net.Conn, config *ServerConfig) (*ServerConn, <-chan NewCha
 	if fullConf.MaxAuthTries == 0 {
 		fullConf.MaxAuthTries = 6
 	}
+	// Check if the config contains any unsupported key exchanges
+	for _, kex := range fullConf.KeyExchanges {
+		if _, ok := serverForbiddenKexAlgos[kex]; ok {
+			return nil, nil, nil, fmt.Errorf("ssh: unsupported key exchange %s for server", kex)
+		}
+	}
 
 	s := &connection{
 		sshConn: sshConn{conn: c},
@@ -204,7 +228,9 @@ func (s *connection) serverHandshake(config *ServerConfig) (*Permissions, error)
 		return nil, errors.New("ssh: server has no host keys")
 	}
 
-	if !config.NoClientAuth && config.PasswordCallback == nil && config.PublicKeyCallback == nil && config.KeyboardInteractiveCallback == nil {
+	if !config.NoClientAuth && config.PasswordCallback == nil && config.PublicKeyCallback == nil &&
+		config.KeyboardInteractiveCallback == nil && (config.GSSAPIWithMICConfig == nil ||
+		config.GSSAPIWithMICConfig.AllowLogin == nil || config.GSSAPIWithMICConfig.Server == nil) {
 		return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")
 	}
 
@@ -258,8 +284,8 @@ func (s *connection) serverHandshake(config *ServerConfig) (*Permissions, error)
 
 func isAcceptableAlgo(algo string) bool {
 	switch algo {
-	case KeyAlgoRSA, KeyAlgoDSA, KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521, KeyAlgoED25519,
+	case KeyAlgoRSA, KeyAlgoDSA, KeyAlgoECDSA256, KeyAlgoECDSA384, KeyAlgoECDSA521, KeyAlgoSKECDSA256, KeyAlgoED25519, KeyAlgoSKED25519,
-		CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoED25519v01:
+		CertAlgoRSAv01, CertAlgoDSAv01, CertAlgoECDSA256v01, CertAlgoECDSA384v01, CertAlgoECDSA521v01, CertAlgoSKECDSA256v01, CertAlgoED25519v01, CertAlgoSKED25519v01:
 		return true
 	}
 	return false
@@ -295,6 +321,55 @@ func checkSourceAddress(addr net.Addr, sourceAddrs string) error {
 	return fmt.Errorf("ssh: remote address %v is not allowed because of source-address restriction", addr)
 }
 
+func gssExchangeToken(gssapiConfig *GSSAPIWithMICConfig, firstToken []byte, s *connection,
+	sessionID []byte, userAuthReq userAuthRequestMsg) (authErr error, perms *Permissions, err error) {
+	gssAPIServer := gssapiConfig.Server
+	defer gssAPIServer.DeleteSecContext()
+	var srcName string
+	for {
+		var (
+			outToken     []byte
+			needContinue bool
+		)
+		outToken, srcName, needContinue, err = gssAPIServer.AcceptSecContext(firstToken)
+		if err != nil {
+			return err, nil, nil
+		}
+		if len(outToken) != 0 {
+			if err := s.transport.writePacket(Marshal(&userAuthGSSAPIToken{
+				Token: outToken,
+			})); err != nil {
+				return nil, nil, err
+			}
+		}
+		if !needContinue {
+			break
+		}
+		packet, err := s.transport.readPacket()
+		if err != nil {
+			return nil, nil, err
+		}
+		userAuthGSSAPITokenReq := &userAuthGSSAPIToken{}
+		if err := Unmarshal(packet, userAuthGSSAPITokenReq); err != nil {
+			return nil, nil, err
+		}
+	}
+	packet, err := s.transport.readPacket()
+	if err != nil {
+		return nil, nil, err
+	}
+	userAuthGSSAPIMICReq := &userAuthGSSAPIMIC{}
+	if err := Unmarshal(packet, userAuthGSSAPIMICReq); err != nil {
+		return nil, nil, err
+	}
+	mic := buildMIC(string(sessionID), userAuthReq.User, userAuthReq.Service, userAuthReq.Method)
+	if err := gssAPIServer.VerifyMIC(mic, userAuthGSSAPIMICReq.MIC); err != nil {
+		return err, nil, nil
+	}
+	perms, authErr = gssapiConfig.AllowLogin(s, srcName)
+	return authErr, perms, nil
+}
+
 // ServerAuthError represents server authentication errors and is
 // sometimes returned by NewServerConn. It appends any authentication
 // errors that may occur, and is returned if all of the authentication
@@ -496,6 +571,49 @@ userAuthLoop:
 				authErr = candidate.result
 				perms = candidate.perms
 			}
+		case "gssapi-with-mic":
+			gssapiConfig := config.GSSAPIWithMICConfig
+			userAuthRequestGSSAPI, err := parseGSSAPIPayload(userAuthReq.Payload)
+			if err != nil {
+				return nil, parseError(msgUserAuthRequest)
+			}
+			// OpenSSH supports Kerberos V5 mechanism only for GSS-API authentication.
+			if userAuthRequestGSSAPI.N == 0 {
+				authErr = fmt.Errorf("ssh: Mechanism negotiation is not supported")
+				break
+			}
+			var i uint32
+			present := false
+			for i = 0; i < userAuthRequestGSSAPI.N; i++ {
+				if userAuthRequestGSSAPI.OIDS[i].Equal(krb5Mesh) {
+					present = true
+					break
+				}
+			}
+			if !present {
+				authErr = fmt.Errorf("ssh: GSSAPI authentication must use the Kerberos V5 mechanism")
+				break
+			}
+			// Initial server response, see RFC 4462 section 3.3.
+			if err := s.transport.writePacket(Marshal(&userAuthGSSAPIResponse{
+				SupportMech: krb5OID,
+			})); err != nil {
+				return nil, err
+			}
+			// Exchange token, see RFC 4462 section 3.4.
+			packet, err := s.transport.readPacket()
+			if err != nil {
+				return nil, err
+			}
+			userAuthGSSAPITokenReq := &userAuthGSSAPIToken{}
+			if err := Unmarshal(packet, userAuthGSSAPITokenReq); err != nil {
+				return nil, err
+			}
+			authErr, perms, err = gssExchangeToken(gssapiConfig, userAuthGSSAPITokenReq.Token, s, sessionID,
+				userAuthReq)
+			if err != nil {
+				return nil, err
+			}
 		default:
 			authErr = fmt.Errorf("ssh: unknown method %q", userAuthReq.Method)
 		}
@@ -522,6 +640,10 @@ userAuthLoop:
 		if config.KeyboardInteractiveCallback != nil {
 			failureMsg.Methods = append(failureMsg.Methods, "keyboard-interactive")
 		}
+		if config.GSSAPIWithMICConfig != nil && config.GSSAPIWithMICConfig.Server != nil &&
+			config.GSSAPIWithMICConfig.AllowLogin != nil {
+			failureMsg.Methods = append(failureMsg.Methods, "gssapi-with-mic")
+		}
 
 		if len(failureMsg.Methods) == 0 {
 			return nil, errors.New("ssh: no authentication methods configured but NoClientAuth is also false")

vendor/golang.org/x/crypto/ssh/ssh_gss.go

@@ -0,0 +1,139 @@
+// Copyright 2011 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 ssh
+
+import (
+	"encoding/asn1"
+	"errors"
+)
+
+var krb5OID []byte
+
+func init() {
+	krb5OID, _ = asn1.Marshal(krb5Mesh)
+}
+
+// GSSAPIClient provides the API to plug-in GSSAPI authentication for client logins.
+type GSSAPIClient interface {
+	// InitSecContext initiates the establishment of a security context for GSS-API between the
+	// ssh client and ssh server. Initially the token parameter should be specified as nil.
+	// The routine may return a outputToken which should be transferred to
+	// the ssh server, where the ssh server will present it to
+	// AcceptSecContext. If no token need be sent, InitSecContext will indicate this by setting
+	// needContinue to false. To complete the context
+	// establishment, one or more reply tokens may be required from the ssh
+	// server;if so, InitSecContext will return a needContinue which is true.
+	// In this case, InitSecContext should be called again when the
+	// reply token is received from the ssh server, passing the reply
+	// token to InitSecContext via the token parameters.
+	// See RFC 2743 section 2.2.1 and RFC 4462 section 3.4.
+	InitSecContext(target string, token []byte, isGSSDelegCreds bool) (outputToken []byte, needContinue bool, err error)
+	// GetMIC generates a cryptographic MIC for the SSH2 message, and places
+	// the MIC in a token for transfer to the ssh server.
+	// The contents of the MIC field are obtained by calling GSS_GetMIC()
+	// over the following, using the GSS-API context that was just
+	// established:
+	//  string    session identifier
+	//  byte      SSH_MSG_USERAUTH_REQUEST
+	//  string    user name
+	//  string    service
+	//  string    "gssapi-with-mic"
+	// See RFC 2743 section 2.3.1 and RFC 4462 3.5.
+	GetMIC(micFiled []byte) ([]byte, error)
+	// Whenever possible, it should be possible for
+	// DeleteSecContext() calls to be successfully processed even
+	// if other calls cannot succeed, thereby enabling context-related
+	// resources to be released.
+	// In addition to deleting established security contexts,
+	// gss_delete_sec_context must also be able to delete "half-built"
+	// security contexts resulting from an incomplete sequence of
+	// InitSecContext()/AcceptSecContext() calls.
+	// See RFC 2743 section 2.2.3.
+	DeleteSecContext() error
+}
+
+// GSSAPIServer provides the API to plug in GSSAPI authentication for server logins.
+type GSSAPIServer interface {
+	// AcceptSecContext allows a remotely initiated security context between the application
+	// and a remote peer to be established by the ssh client. The routine may return a
+	// outputToken which should be transferred to the ssh client,
+	// where the ssh client will present it to InitSecContext.
+	// If no token need be sent, AcceptSecContext will indicate this
+	// by setting the needContinue to false. To
+	// complete the context establishment, one or more reply tokens may be
+	// required from the ssh client. if so, AcceptSecContext
+	// will return a needContinue which is true, in which case it
+	// should be called again when the reply token is received from the ssh
+	// client, passing the token to AcceptSecContext via the
+	// token parameters.
+	// The srcName return value is the authenticated username.
+	// See RFC 2743 section 2.2.2 and RFC 4462 section 3.4.
+	AcceptSecContext(token []byte) (outputToken []byte, srcName string, needContinue bool, err error)
+	// VerifyMIC verifies that a cryptographic MIC, contained in the token parameter,
+	// fits the supplied message is received from the ssh client.
+	// See RFC 2743 section 2.3.2.
+	VerifyMIC(micField []byte, micToken []byte) error
+	// Whenever possible, it should be possible for
+	// DeleteSecContext() calls to be successfully processed even
+	// if other calls cannot succeed, thereby enabling context-related
+	// resources to be released.
+	// In addition to deleting established security contexts,
+	// gss_delete_sec_context must also be able to delete "half-built"
+	// security contexts resulting from an incomplete sequence of
+	// InitSecContext()/AcceptSecContext() calls.
+	// See RFC 2743 section 2.2.3.
+	DeleteSecContext() error
+}
+
+var (
+	// OpenSSH supports Kerberos V5 mechanism only for GSS-API authentication,
+	// so we also support the krb5 mechanism only.
+	// See RFC 1964 section 1.
+	krb5Mesh = asn1.ObjectIdentifier{1, 2, 840, 113554, 1, 2, 2}
+)
+
+// The GSS-API authentication method is initiated when the client sends an SSH_MSG_USERAUTH_REQUEST
+// See RFC 4462 section 3.2.
+type userAuthRequestGSSAPI struct {
+	N    uint32
+	OIDS []asn1.ObjectIdentifier
+}
+
+func parseGSSAPIPayload(payload []byte) (*userAuthRequestGSSAPI, error) {
+	n, rest, ok := parseUint32(payload)
+	if !ok {
+		return nil, errors.New("parse uint32 failed")
+	}
+	s := &userAuthRequestGSSAPI{
+		N:    n,
+		OIDS: make([]asn1.ObjectIdentifier, n),
+	}
+	for i := 0; i < int(n); i++ {
+		var (
+			desiredMech []byte
+			err         error
+		)
+		desiredMech, rest, ok = parseString(rest)
+		if !ok {
+			return nil, errors.New("parse string failed")
+		}
+		if rest, err = asn1.Unmarshal(desiredMech, &s.OIDS[i]); err != nil {
+			return nil, err
+		}
+
+	}
+	return s, nil
+}
+
+// See RFC 4462 section 3.6.
+func buildMIC(sessionID string, username string, service string, authMethod string) []byte {
+	out := make([]byte, 0, 0)
+	out = appendString(out, sessionID)
+	out = append(out, msgUserAuthRequest)
+	out = appendString(out, username)
+	out = appendString(out, service)
+	out = appendString(out, authMethod)
+	return out
+}

vendor/golang.org/x/crypto/ssh/terminal/terminal.go

@@ -947,6 +947,10 @@ func readPasswordLine(reader io.Reader) ([]byte, error) {
 		n, err := reader.Read(buf[:])
 		if n > 0 {
 			switch buf[0] {
+			case '\b':
+				if len(ret) > 0 {
+					ret = ret[:len(ret)-1]
+				}
 			case '\n':
 				return ret, nil
 			case '\r':

vendor/golang.org/x/crypto/ssh/terminal/util_windows.go

@@ -85,8 +85,8 @@ func ReadPassword(fd int) ([]byte, error) {
 	}
 	old := st
 
-	st &^= (windows.ENABLE_ECHO_INPUT)
+	st &^= (windows.ENABLE_ECHO_INPUT | windows.ENABLE_LINE_INPUT)
-	st |= (windows.ENABLE_PROCESSED_INPUT | windows.ENABLE_LINE_INPUT | windows.ENABLE_PROCESSED_OUTPUT)
+	st |= (windows.ENABLE_PROCESSED_OUTPUT | windows.ENABLE_PROCESSED_INPUT)
 	if err := windows.SetConsoleMode(windows.Handle(fd), st); err != nil {
 		return nil, err
 	}