go.mod: update golang.org/x dependencies

Update golang.org/x dependencies to their latest tagged versions.

Change-Id: Iae75e5fcbcfe3709820dd66638a763f662f8d939
Reviewed-on: https://go-review.googlesource.com/c/crypto/+/603396
Auto-Submit: Gopher Robot <gobot@golang.org>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: David Chase <drchase@google.com>

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2009 The Go Authors. All rights reserved.
+Copyright 2009 The Go Authors.
 
 Redistribution and use in source and binary forms, with or without
 modification, are permitted provided that the following conditions are
@@ -10,7 +10,7 @@ notice, this list of conditions and the following disclaimer.
 copyright notice, this list of conditions and the following disclaimer
 in the documentation and/or other materials provided with the
 distribution.
-   * Neither the name of Google Inc. nor the names of its
+   * Neither the name of Google LLC nor the names of its
 contributors may be used to endorse or promote products derived from
 this software without specific prior written permission.
 

acme/acme_test.go

@@ -354,11 +354,12 @@ func TestWaitAuthorization(t *testing.T) {
 		})
 	}
 	t.Run("context cancel", func(t *testing.T) {
-		ctx, cancel := context.WithTimeout(context.Background(), 200*time.Millisecond)
+		ctx, cancel := context.WithCancel(context.Background())
 		defer cancel()
 		_, err := runWaitAuthorization(ctx, t, func(w http.ResponseWriter, r *http.Request) {
 			w.Header().Set("Retry-After", "60")
 			fmt.Fprintf(w, `{"status":"pending"}`)
+			time.AfterFunc(1*time.Millisecond, cancel)
 		})
 		if err == nil {
 			t.Error("err is nil")
@@ -373,28 +374,14 @@ func runWaitAuthorization(ctx context.Context, t *testing.T, h http.HandlerFunc)
 		h(w, r)
 	}))
 	defer ts.Close()
-	type res struct {
-		authz *Authorization
-		err   error
+
+	client := &Client{
+		Key:          testKey,
+		DirectoryURL: ts.URL,
+		dir:          &Directory{},
+		KID:          "some-key-id", // set to avoid lookup attempt
 	}
-	ch := make(chan res, 1)
-	go func() {
-		client := &Client{
-			Key:          testKey,
-			DirectoryURL: ts.URL,
-			dir:          &Directory{},
-			KID:          "some-key-id", // set to avoid lookup attempt
-		}
-		a, err := client.WaitAuthorization(ctx, ts.URL)
-		ch <- res{a, err}
-	}()
-	select {
-	case <-time.After(3 * time.Second):
-		t.Fatal("WaitAuthorization took too long to return")
-	case v := <-ch:
-		return v.authz, v.err
-	}
-	panic("runWaitAuthorization: out of select")
+	return client.WaitAuthorization(ctx, ts.URL)
 }
 
 func TestRevokeAuthorization(t *testing.T) {

acme/autocert/autocert_test.go

@@ -427,18 +427,7 @@ func TestGetCertificate(t *testing.T) {
 
 			man.Client = &acme.Client{DirectoryURL: s.URL()}
 
-			var tlscert *tls.Certificate
-			var err error
-			done := make(chan struct{})
-			go func() {
-				tlscert, err = man.GetCertificate(tt.hello)
-				close(done)
-			}()
-			select {
-			case <-time.After(time.Minute):
-				t.Fatal("man.GetCertificate took too long to return")
-			case <-done:
-			}
+			tlscert, err := man.GetCertificate(tt.hello)
 			if tt.expectError != "" {
 				if err == nil {
 					t.Fatal("expected error, got certificate")
@@ -515,15 +504,12 @@ func TestGetCertificate_failedAttempt(t *testing.T) {
 	if _, err := man.GetCertificate(hello); err == nil {
 		t.Error("GetCertificate: err is nil")
 	}
-	select {
-	case <-time.After(5 * time.Second):
-		t.Errorf("took too long to remove the %q state", exampleCertKey)
-	case <-done:
-		man.stateMu.Lock()
-		defer man.stateMu.Unlock()
-		if v, exist := man.state[exampleCertKey]; exist {
-			t.Errorf("state exists for %v: %+v", exampleCertKey, v)
-		}
+
+	<-done
+	man.stateMu.Lock()
+	defer man.stateMu.Unlock()
+	if v, exist := man.state[exampleCertKey]; exist {
+		t.Errorf("state exists for %v: %+v", exampleCertKey, v)
 	}
 }
 
@@ -542,8 +528,9 @@ func TestRevokeFailedAuthz(t *testing.T) {
 		t.Fatal("expected GetCertificate to fail")
 	}
 
-	start := time.Now()
-	for time.Since(start) < 3*time.Second {
+	logTicker := time.NewTicker(3 * time.Second)
+	defer logTicker.Stop()
+	for {
 		authz, err := m.Client.GetAuthorization(context.Background(), ca.URL()+"/authz/0")
 		if err != nil {
 			t.Fatal(err)
@@ -551,10 +538,14 @@ func TestRevokeFailedAuthz(t *testing.T) {
 		if authz.Status == acme.StatusDeactivated {
 			return
 		}
+
+		select {
+		case <-logTicker.C:
+			t.Logf("still waiting on revocations")
+		default:
+		}
 		time.Sleep(50 * time.Millisecond)
 	}
-	t.Error("revocations took too long")
-
 }
 
 func TestHTTPHandlerDefaultFallback(t *testing.T) {

acme/http.go

@@ -15,6 +15,7 @@ import (
 	"io"
 	"math/big"
 	"net/http"
+	"runtime/debug"
 	"strconv"
 	"strings"
 	"time"
@@ -271,9 +272,27 @@ func (c *Client) httpClient() *http.Client {
 }
 
 // packageVersion is the version of the module that contains this package, for
-// sending as part of the User-Agent header. It's set in version_go112.go.
+// sending as part of the User-Agent header.
 var packageVersion string
 
+func init() {
+	// Set packageVersion if the binary was built in modules mode and x/crypto
+	// was not replaced with a different module.
+	info, ok := debug.ReadBuildInfo()
+	if !ok {
+		return
+	}
+	for _, m := range info.Deps {
+		if m.Path != "golang.org/x/crypto" {
+			continue
+		}
+		if m.Replace == nil {
+			packageVersion = m.Version
+		}
+		break
+	}
+}
+
 // userAgent returns the User-Agent header value. It includes the package name,
 // the module version (if available), and the c.UserAgent value (if set).
 func (c *Client) userAgent() string {

acme/rfc8555.go

@@ -117,7 +117,7 @@ func (c *Client) updateRegRFC(ctx context.Context, a *Account) (*Account, error)
 	return responseAccount(res)
 }
 
-// getGegRFC is equivalent to c.GetReg but for CAs implementing RFC 8555.
+// getRegRFC is equivalent to c.GetReg but for CAs implementing RFC 8555.
 // It expects c.Discover to have already been called.
 func (c *Client) getRegRFC(ctx context.Context) (*Account, error) {
 	req := json.RawMessage(`{"onlyReturnExisting": true}`)

acme/rfc8555_test.go

@@ -177,8 +177,7 @@ func TestRFC_postKID(t *testing.T) {
 	}))
 	defer ts.Close()
 
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	defer cancel()
+	ctx := context.Background()
 	cl := &Client{
 		Key:          testKey,
 		DirectoryURL: ts.URL,
@@ -316,8 +315,7 @@ func TestRFC_Register(t *testing.T) {
 	s.start()
 	defer s.close()
 
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	defer cancel()
+	ctx := context.Background()
 	cl := &Client{
 		Key:          testKeyEC,
 		DirectoryURL: s.url("/"),
@@ -454,8 +452,7 @@ func TestRFC_RegisterExternalAccountBinding(t *testing.T) {
 	s.start()
 	defer s.close()
 
-	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
-	defer cancel()
+	ctx := context.Background()
 	cl := &Client{
 		Key:          testKeyEC,
 		DirectoryURL: s.url("/"),
@@ -867,24 +864,13 @@ func testWaitOrderStatus(t *testing.T, okStatus string) {
 	s.start()
 	defer s.close()
 
-	var order *Order
-	var err error
-	done := make(chan struct{})
-	go func() {
-		cl := &Client{Key: testKeyEC, DirectoryURL: s.url("/")}
-		order, err = cl.WaitOrder(context.Background(), s.url("/orders/1"))
-		close(done)
-	}()
-	select {
-	case <-time.After(3 * time.Second):
-		t.Fatal("WaitOrder took too long to return")
-	case <-done:
-		if err != nil {
-			t.Fatalf("WaitOrder: %v", err)
-		}
-		if order.Status != okStatus {
-			t.Errorf("order.Status = %q; want %q", order.Status, okStatus)
-		}
+	cl := &Client{Key: testKeyEC, DirectoryURL: s.url("/")}
+	order, err := cl.WaitOrder(context.Background(), s.url("/orders/1"))
+	if err != nil {
+		t.Fatalf("WaitOrder: %v", err)
+	}
+	if order.Status != okStatus {
+		t.Errorf("order.Status = %q; want %q", order.Status, okStatus)
 	}
 }
 
@@ -909,30 +895,20 @@ func TestRFC_WaitOrderError(t *testing.T) {
 	s.start()
 	defer s.close()
 
-	var err error
-	done := make(chan struct{})
-	go func() {
-		cl := &Client{Key: testKeyEC, DirectoryURL: s.url("/")}
-		_, err = cl.WaitOrder(context.Background(), s.url("/orders/1"))
-		close(done)
-	}()
-	select {
-	case <-time.After(3 * time.Second):
-		t.Fatal("WaitOrder took too long to return")
-	case <-done:
-		if err == nil {
-			t.Fatal("WaitOrder returned nil error")
-		}
-		e, ok := err.(*OrderError)
-		if !ok {
-			t.Fatalf("err = %v (%T); want OrderError", err, err)
-		}
-		if e.OrderURL != s.url("/orders/1") {
-			t.Errorf("e.OrderURL = %q; want %q", e.OrderURL, s.url("/orders/1"))
-		}
-		if e.Status != StatusInvalid {
-			t.Errorf("e.Status = %q; want %q", e.Status, StatusInvalid)
-		}
+	cl := &Client{Key: testKeyEC, DirectoryURL: s.url("/")}
+	_, err := cl.WaitOrder(context.Background(), s.url("/orders/1"))
+	if err == nil {
+		t.Fatal("WaitOrder returned nil error")
+	}
+	e, ok := err.(*OrderError)
+	if !ok {
+		t.Fatalf("err = %v (%T); want OrderError", err, err)
+	}
+	if e.OrderURL != s.url("/orders/1") {
+		t.Errorf("e.OrderURL = %q; want %q", e.OrderURL, s.url("/orders/1"))
+	}
+	if e.Status != StatusInvalid {
+		t.Errorf("e.Status = %q; want %q", e.Status, StatusInvalid)
 	}
 }
 
@@ -972,8 +948,7 @@ func TestRFC_CreateOrderCert(t *testing.T) {
 	})
 	s.start()
 	defer s.close()
-	ctx, cancel := context.WithTimeout(context.Background(), 3*time.Second)
-	defer cancel()
+	ctx := context.Background()
 
 	cl := &Client{Key: testKeyEC, DirectoryURL: s.url("/")}
 	cert, curl, err := cl.CreateOrderCert(ctx, s.url("/pleaseissue"), csr, true)

acme/version_go112.go

@@ -1,28 +0,0 @@
-// 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.
-
-//go:build go1.12
-// +build go1.12
-
-package acme
-
-import "runtime/debug"
-
-func init() {
-	// Set packageVersion if the binary was built in modules mode and x/crypto
-	// was not replaced with a different module.
-	info, ok := debug.ReadBuildInfo()
-	if !ok {
-		return
-	}
-	for _, m := range info.Deps {
-		if m.Path != "golang.org/x/crypto" {
-			continue
-		}
-		if m.Replace == nil {
-			packageVersion = m.Version
-		}
-		break
-	}
-}

argon2/blamka_amd64.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
 
 package argon2
 

argon2/blamka_amd64.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
 
 #include "textflag.h"
 
@@ -200,8 +199,8 @@ TEXT ·mixBlocksSSE2(SB), 4, $0-32
 	MOVQ out+0(FP), DX
 	MOVQ a+8(FP), AX
 	MOVQ b+16(FP), BX
-	MOVQ a+24(FP), CX
-	MOVQ $128, BP
+	MOVQ c+24(FP), CX
+	MOVQ $128, DI
 
 loop:
 	MOVOU 0(AX), X0
@@ -214,7 +213,7 @@ loop:
 	ADDQ  $16, BX
 	ADDQ  $16, CX
 	ADDQ  $16, DX
-	SUBQ  $2, BP
+	SUBQ  $2, DI
 	JA    loop
 	RET
 
@@ -223,8 +222,8 @@ TEXT ·xorBlocksSSE2(SB), 4, $0-32
 	MOVQ out+0(FP), DX
 	MOVQ a+8(FP), AX
 	MOVQ b+16(FP), BX
-	MOVQ a+24(FP), CX
-	MOVQ $128, BP
+	MOVQ c+24(FP), CX
+	MOVQ $128, DI
 
 loop:
 	MOVOU 0(AX), X0
@@ -239,6 +238,6 @@ loop:
 	ADDQ  $16, BX
 	ADDQ  $16, CX
 	ADDQ  $16, DX
-	SUBQ  $2, BP
+	SUBQ  $2, DI
 	JA    loop
 	RET

argon2/blamka_ref.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build !amd64 || purego || !gc
-// +build !amd64 purego !gc
 
 package argon2
 

bcrypt/bcrypt.go

@@ -4,7 +4,7 @@
 
 // Package bcrypt implements Provos and Mazières's bcrypt adaptive hashing
 // algorithm. See http://www.usenix.org/event/usenix99/provos/provos.pdf
-package bcrypt // import "golang.org/x/crypto/bcrypt"
+package bcrypt
 
 // The code is a port of Provos and Mazières's C implementation.
 import (
@@ -82,11 +82,20 @@ type hashed struct {
 	minor byte
 }
 
+// ErrPasswordTooLong is returned when the password passed to
+// GenerateFromPassword is too long (i.e. > 72 bytes).
+var ErrPasswordTooLong = errors.New("bcrypt: password length exceeds 72 bytes")
+
 // GenerateFromPassword returns the bcrypt hash of the password at the given
 // cost. If the cost given is less than MinCost, the cost will be set to
 // DefaultCost, instead. Use CompareHashAndPassword, as defined in this package,
 // to compare the returned hashed password with its cleartext version.
+// GenerateFromPassword does not accept passwords longer than 72 bytes, which
+// is the longest password bcrypt will operate on.
 func GenerateFromPassword(password []byte, cost int) ([]byte, error) {
+	if len(password) > 72 {
+		return nil, ErrPasswordTooLong
+	}
 	p, err := newFromPassword(password, cost)
 	if err != nil {
 		return nil, err

bcrypt/bcrypt_test.go

@@ -241,3 +241,10 @@ func TestNoSideEffectsFromCompare(t *testing.T) {
 		t.Errorf("got=%q want=%q", got, want)
 	}
 }
+
+func TestPasswordTooLong(t *testing.T) {
+	_, err := GenerateFromPassword(make([]byte, 73), 1)
+	if err != ErrPasswordTooLong {
+		t.Errorf("unexpected error: got %q, want %q", err, ErrPasswordTooLong)
+	}
+}

blake2b/blake2bAVX2_amd64.go

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.7 && amd64 && gc && !purego
-// +build go1.7,amd64,gc,!purego
+//go:build amd64 && gc && !purego
 
 package blake2b
 

blake2b/blake2bAVX2_amd64.s

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.7 && amd64 && gc && !purego
-// +build go1.7,amd64,gc,!purego
+//go:build amd64 && gc && !purego
 
 #include "textflag.h"
 

blake2b/blake2b_amd64.go

@@ -1,25 +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.
-
-//go:build !go1.7 && amd64 && gc && !purego
-// +build !go1.7,amd64,gc,!purego
-
-package blake2b
-
-import "golang.org/x/sys/cpu"
-
-func init() {
-	useSSE4 = cpu.X86.HasSSE41
-}
-
-//go:noescape
-func hashBlocksSSE4(h *[8]uint64, c *[2]uint64, flag uint64, blocks []byte)
-
-func hashBlocks(h *[8]uint64, c *[2]uint64, flag uint64, blocks []byte) {
-	if useSSE4 {
-		hashBlocksSSE4(h, c, flag, blocks)
-	} else {
-		hashBlocksGeneric(h, c, flag, blocks)
-	}
-}

blake2b/blake2b_amd64.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
 
 #include "textflag.h"
 

blake2b/blake2b_ref.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build !amd64 || purego || !gc
-// +build !amd64 purego !gc
 
 package blake2b
 

blake2b/register.go

@@ -2,9 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.9
-// +build go1.9
-
 package blake2b
 
 import (

blake2s/blake2s.go

@@ -16,9 +16,10 @@
 //
 // BLAKE2X is a construction to compute hash values larger than 32 bytes. It
 // can produce hash values between 0 and 65535 bytes.
-package blake2s // import "golang.org/x/crypto/blake2s"
+package blake2s
 
 import (
+	"crypto"
 	"encoding/binary"
 	"errors"
 	"hash"
@@ -55,6 +56,13 @@ func Sum256(data []byte) [Size]byte {
 // and BinaryUnmarshaler for state (de)serialization as documented by hash.Hash.
 func New256(key []byte) (hash.Hash, error) { return newDigest(Size, key) }
 
+func init() {
+	crypto.RegisterHash(crypto.BLAKE2s_256, func() hash.Hash {
+		h, _ := New256(nil)
+		return h
+	})
+}
+
 // New128 returns a new hash.Hash computing the BLAKE2s-128 checksum given a
 // non-empty key. Note that a 128-bit digest is too small to be secure as a
 // cryptographic hash and should only be used as a MAC, thus the key argument

blake2s/blake2s_386.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build 386 && gc && !purego
-// +build 386,gc,!purego
 
 package blake2s
 

blake2s/blake2s_386.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build 386 && gc && !purego
-// +build 386,gc,!purego
 
 #include "textflag.h"
 

blake2s/blake2s_amd64.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
 
 package blake2s
 

blake2s/blake2s_amd64.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
 
 #include "textflag.h"
 

blake2s/blake2s_ref.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build (!amd64 && !386) || !gc || purego
-// +build !amd64,!386 !gc purego
 
 package blake2s
 

blake2s/register.go

@@ -1,22 +0,0 @@
-// Copyright 2017 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.
-
-//go:build go1.9
-// +build go1.9
-
-package blake2s
-
-import (
-	"crypto"
-	"hash"
-)
-
-func init() {
-	newHash256 := func() hash.Hash {
-		h, _ := New256(nil)
-		return h
-	}
-
-	crypto.RegisterHash(crypto.BLAKE2s_256, newHash256)
-}

blowfish/cipher.go

@@ -11,7 +11,7 @@
 // Deprecated: any new system should use AES (from crypto/aes, if necessary in
 // an AEAD mode like crypto/cipher.NewGCM) or XChaCha20-Poly1305 (from
 // golang.org/x/crypto/chacha20poly1305).
-package blowfish // import "golang.org/x/crypto/blowfish"
+package blowfish
 
 // The code is a port of Bruce Schneier's C implementation.
 // See https://www.schneier.com/blowfish.html.

bn256/bn256.go

@@ -23,7 +23,7 @@
 // elliptic curve. This package is frozen, and not implemented in constant time.
 // There is a more complete implementation at github.com/cloudflare/bn256, but
 // note that it suffers from the same security issues of the underlying curve.
-package bn256 // import "golang.org/x/crypto/bn256"
+package bn256
 
 import (
 	"crypto/rand"

cast5/cast5.go

@@ -11,7 +11,7 @@
 // Deprecated: any new system should use AES (from crypto/aes, if necessary in
 // an AEAD mode like crypto/cipher.NewGCM) or XChaCha20-Poly1305 (from
 // golang.org/x/crypto/chacha20poly1305).
-package cast5 // import "golang.org/x/crypto/cast5"
+package cast5
 
 import (
 	"errors"

chacha20/chacha_arm64.go

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.11 && gc && !purego
-// +build go1.11,gc,!purego
+//go:build gc && !purego
 
 package chacha20
 

chacha20/chacha_arm64.s

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.11 && gc && !purego
-// +build go1.11,gc,!purego
+//go:build gc && !purego
 
 #include "textflag.h"
 

chacha20/chacha_noasm.go

@@ -2,8 +2,7 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build (!arm64 && !s390x && !ppc64le) || (arm64 && !go1.11) || !gc || purego
-// +build !arm64,!s390x,!ppc64le arm64,!go1.11 !gc purego
+//go:build (!arm64 && !s390x && !ppc64le) || !gc || purego
 
 package chacha20
 

chacha20/chacha_ppc64le.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 package chacha20
 

chacha20/chacha_ppc64le.s

@@ -20,7 +20,6 @@
 // due to the calling conventions and initialization of constants.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 #include "textflag.h"
 
@@ -34,6 +33,9 @@
 #define CONSTBASE  R16
 #define BLOCKS R17
 
+// for VPERMXOR
+#define MASK  R18
+
 DATA consts<>+0x00(SB)/8, $0x3320646e61707865
 DATA consts<>+0x08(SB)/8, $0x6b20657479622d32
 DATA consts<>+0x10(SB)/8, $0x0000000000000001
@@ -54,7 +56,11 @@ 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
+DATA consts<>+0xa0(SB)/8, $0x5566774411223300
+DATA consts<>+0xa8(SB)/8, $0xddeeffcc99aabb88
+DATA consts<>+0xb0(SB)/8, $0x6677445522330011
+DATA consts<>+0xb8(SB)/8, $0xeeffccddaabb8899
+GLOBL consts<>(SB), RODATA, $0xc0
 
 //func chaCha20_ctr32_vsx(out, inp *byte, len int, key *[8]uint32, counter *uint32)
 TEXT ·chaCha20_ctr32_vsx(SB),NOSPLIT,$64-40
@@ -71,6 +77,9 @@ TEXT ·chaCha20_ctr32_vsx(SB),NOSPLIT,$64-40
 	MOVD $48, R10
 	MOVD $64, R11
 	SRD $6, LEN, BLOCKS
+	// for VPERMXOR
+	MOVD $consts<>+0xa0(SB), MASK
+	MOVD $16, R20
 	// V16
 	LXVW4X (CONSTBASE)(R0), VS48
 	ADD $80,CONSTBASE
@@ -88,6 +97,10 @@ TEXT ·chaCha20_ctr32_vsx(SB),NOSPLIT,$64-40
 	// V28
 	LXVW4X (CONSTBASE)(R11), VS60
 
+	// Load mask constants for VPERMXOR
+	LXVW4X (MASK)(R0), V20
+	LXVW4X (MASK)(R20), V21
+
 	// splat slot from V19 -> V26
 	VSPLTW $0, V19, V26
 
@@ -98,7 +111,7 @@ TEXT ·chaCha20_ctr32_vsx(SB),NOSPLIT,$64-40
 
 	MOVD $10, R14
 	MOVD R14, CTR
-
+	PCALIGN $16
 loop_outer_vsx:
 	// V0, V1, V2, V3
 	LXVW4X (R0)(CONSTBASE), VS32
@@ -129,22 +142,17 @@ loop_outer_vsx:
 	VSPLTISW $12, V28
 	VSPLTISW $8, V29
 	VSPLTISW $7, V30
-
+	PCALIGN $16
 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
+	VPERMXOR V12, V0, V21, V12
+	VPERMXOR V13, V1, V21, V13
+	VPERMXOR V14, V2, V21, V14
+	VPERMXOR V15, V3, V21, V15
 
 	VADDUWM V8, V12, V8
 	VADDUWM V9, V13, V9
@@ -166,15 +174,10 @@ loop_vsx:
 	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
+	VPERMXOR V12, V0, V20, V12
+	VPERMXOR V13, V1, V20, V13
+	VPERMXOR V14, V2, V20, V14
+	VPERMXOR V15, V3, V20, V15
 
 	VADDUWM V8, V12, V8
 	VADDUWM V9, V13, V9
@@ -196,15 +199,10 @@ loop_vsx:
 	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
+	VPERMXOR V15, V0, V21, V15
+	VPERMXOR V12, V1, V21, V12
+	VPERMXOR V13, V2, V21, V13
+	VPERMXOR V14, V3, V21, V14
 
 	VADDUWM V10, V15, V10
 	VADDUWM V11, V12, V11
@@ -226,15 +224,10 @@ loop_vsx:
 	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
+	VPERMXOR V15, V0, V20, V15
+	VPERMXOR V12, V1, V20, V12
+	VPERMXOR V13, V2, V20, V13
+	VPERMXOR V14, V3, V20, V14
 
 	VADDUWM V10, V15, V10
 	VADDUWM V11, V12, V11
@@ -250,48 +243,48 @@ loop_vsx:
 	VRLW V6, V30, V6
 	VRLW V7, V30, V7
 	VRLW V4, V30, V4
-	BC   16, LT, loop_vsx
+	BDNZ   loop_vsx
 
 	VADDUWM V12, V26, V12
 
-	WORD $0x13600F8C		// VMRGEW V0, V1, V27
-	WORD $0x13821F8C		// VMRGEW V2, V3, V28
+	VMRGEW V0, V1, V27
+	VMRGEW V2, V3, V28
 
-	WORD $0x10000E8C		// VMRGOW V0, V1, V0
-	WORD $0x10421E8C		// VMRGOW V2, V3, V2
+	VMRGOW V0, V1, V0
+	VMRGOW V2, V3, V2
 
-	WORD $0x13A42F8C		// VMRGEW V4, V5, V29
-	WORD $0x13C63F8C		// VMRGEW V6, V7, V30
+	VMRGEW V4, V5, V29
+	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
+	VMRGOW V4, V5, V4
+	VMRGOW V6, V7, V6
 
-	WORD $0x13684F8C		// VMRGEW V8, V9, V27
-	WORD $0x138A5F8C		// VMRGEW V10, V11, V28
+	VMRGEW V8, V9, V27
+	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
+	VMRGOW V8, V9, V8
+	VMRGOW V10, V11, V10
 
-	WORD $0x13AC6F8C		// VMRGEW V12, V13, V29
-	WORD $0x13CE7F8C		// VMRGEW V14, V15, V30
+	VMRGEW V12, V13, V29
+	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
+	VMRGOW V12, V13, V12
+	VMRGOW V14, V15, V14
 
 	VSPLTISW $4, V27
 	VADDUWM V26, V27, V26
@@ -432,7 +425,7 @@ tail_vsx:
 	ADD $-1, R11, R12
 	ADD $-1, INP
 	ADD $-1, OUT
-
+	PCALIGN $16
 looptail_vsx:
 	// Copying the result to OUT
 	// in bytes.
@@ -440,7 +433,7 @@ looptail_vsx:
 	MOVBZU 1(INP), TMP
 	XOR    KEY, TMP, KEY
 	MOVBU  KEY, 1(OUT)
-	BC     16, LT, looptail_vsx
+	BDNZ   looptail_vsx
 
 	// Clear the stack values
 	STXVW4X VS48, (R11)(R0)

chacha20/chacha_s390x.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 package chacha20
 

chacha20/chacha_s390x.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 #include "go_asm.h"
 #include "textflag.h"

chacha20poly1305/chacha20poly1305.go

@@ -5,7 +5,7 @@
 // Package chacha20poly1305 implements the ChaCha20-Poly1305 AEAD and its
 // extended nonce variant XChaCha20-Poly1305, as specified in RFC 8439 and
 // draft-irtf-cfrg-xchacha-01.
-package chacha20poly1305 // import "golang.org/x/crypto/chacha20poly1305"
+package chacha20poly1305
 
 import (
 	"crypto/cipher"

chacha20poly1305/chacha20poly1305_amd64.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 package chacha20poly1305
 

chacha20poly1305/chacha20poly1305_amd64.s

@@ -5,7 +5,6 @@
 // This file was originally from https://golang.org/cl/24717 by Vlad Krasnov of CloudFlare.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 #include "textflag.h"
 // General register allocation
@@ -184,11 +183,31 @@ GLOBL ·andMask<>(SB), (NOPTR+RODATA), $240
 #define shiftD1Right BYTE $0x66; BYTE $0x45; BYTE $0x0f; BYTE $0x3a; BYTE $0x0f; BYTE $0xd2; BYTE $0x04 // PALIGNR $4, X10, X10
 #define shiftD2Right BYTE $0x66; BYTE $0x45; BYTE $0x0f; BYTE $0x3a; BYTE $0x0f; BYTE $0xdb; BYTE $0x04 // PALIGNR $4, X11, X11
 #define shiftD3Right BYTE $0x66; BYTE $0x45; BYTE $0x0f; BYTE $0x3a; BYTE $0x0f; BYTE $0xff; BYTE $0x04 // PALIGNR $4, X15, X15
+
 // Some macros
+
+// ROL rotates the uint32s in register R left by N bits, using temporary T.
+#define ROL(N, R, T) \
+	MOVO R, T; PSLLL $(N), T; PSRLL $(32-(N)), R; PXOR T, R
+
+// ROL16 rotates the uint32s in register R left by 16, using temporary T if needed.
+#ifdef GOAMD64_v2
+#define ROL16(R, T) PSHUFB ·rol16<>(SB), R
+#else
+#define ROL16(R, T) ROL(16, R, T)
+#endif
+
+// ROL8 rotates the uint32s in register R left by 8, using temporary T if needed.
+#ifdef GOAMD64_v2
+#define ROL8(R, T) PSHUFB ·rol8<>(SB), R
+#else
+#define ROL8(R, T) ROL(8, R, T)
+#endif
+
 #define chachaQR(A, B, C, D, T) \
-	PADDD B, A; PXOR A, D; PSHUFB ·rol16<>(SB), D                            \
+	PADDD B, A; PXOR A, D; ROL16(D, T) \
 	PADDD D, C; PXOR C, B; MOVO B, T; PSLLL $12, T; PSRLL $20, B; PXOR T, B \
-	PADDD B, A; PXOR A, D; PSHUFB ·rol8<>(SB), D                             \
+	PADDD B, A; PXOR A, D; ROL8(D, T) \
 	PADDD D, C; PXOR C, B; MOVO B, T; PSLLL $7, T; PSRLL $25, B; PXOR T, B
 
 #define chachaQR_AVX2(A, B, C, D, T) \

chacha20poly1305/chacha20poly1305_noasm.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build !amd64 || !gc || purego
-// +build !amd64 !gc purego
 
 package chacha20poly1305
 

cryptobyte/asn1.go

@@ -264,36 +264,35 @@ func (s *String) ReadASN1Boolean(out *bool) bool {
 	return true
 }
 
-var bigIntType = reflect.TypeOf((*big.Int)(nil)).Elem()
-
 // ReadASN1Integer decodes an ASN.1 INTEGER into out and advances. If out does
-// not point to an integer or to a big.Int, it panics. It reports whether the
-// read was successful.
+// not point to an integer, to a big.Int, or to a []byte it panics. Only
+// positive and zero values can be decoded into []byte, and they are returned as
+// big-endian binary values that share memory with s. Positive values will have
+// no leading zeroes, and zero will be returned as a single zero byte.
+// ReadASN1Integer reports whether the read was successful.
 func (s *String) ReadASN1Integer(out interface{}) bool {
-	if reflect.TypeOf(out).Kind() != reflect.Ptr {
-		panic("out is not a pointer")
-	}
-	switch reflect.ValueOf(out).Elem().Kind() {
-	case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
+	switch out := out.(type) {
+	case *int, *int8, *int16, *int32, *int64:
 		var i int64
 		if !s.readASN1Int64(&i) || reflect.ValueOf(out).Elem().OverflowInt(i) {
 			return false
 		}
 		reflect.ValueOf(out).Elem().SetInt(i)
 		return true
-	case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+	case *uint, *uint8, *uint16, *uint32, *uint64:
 		var u uint64
 		if !s.readASN1Uint64(&u) || reflect.ValueOf(out).Elem().OverflowUint(u) {
 			return false
 		}
 		reflect.ValueOf(out).Elem().SetUint(u)
 		return true
-	case reflect.Struct:
-		if reflect.TypeOf(out).Elem() == bigIntType {
-			return s.readASN1BigInt(out.(*big.Int))
-		}
+	case *big.Int:
+		return s.readASN1BigInt(out)
+	case *[]byte:
+		return s.readASN1Bytes(out)
+	default:
+		panic("out does not point to an integer type")
 	}
-	panic("out does not point to an integer type")
 }
 
 func checkASN1Integer(bytes []byte) bool {
@@ -333,6 +332,21 @@ func (s *String) readASN1BigInt(out *big.Int) bool {
 	return true
 }
 
+func (s *String) readASN1Bytes(out *[]byte) bool {
+	var bytes String
+	if !s.ReadASN1(&bytes, asn1.INTEGER) || !checkASN1Integer(bytes) {
+		return false
+	}
+	if bytes[0]&0x80 == 0x80 {
+		return false
+	}
+	for len(bytes) > 1 && bytes[0] == 0 {
+		bytes = bytes[1:]
+	}
+	*out = bytes
+	return true
+}
+
 func (s *String) readASN1Int64(out *int64) bool {
 	var bytes String
 	if !s.ReadASN1(&bytes, asn1.INTEGER) || !checkASN1Integer(bytes) || !asn1Signed(out, bytes) {
@@ -417,6 +431,14 @@ func (s *String) readBase128Int(out *int) bool {
 		}
 		ret <<= 7
 		b := s.read(1)[0]
+
+		// ITU-T X.690, section 8.19.2:
+		// The subidentifier shall be encoded in the fewest possible octets,
+		// that is, the leading octet of the subidentifier shall not have the value 0x80.
+		if i == 0 && b == 0x80 {
+			return false
+		}
+
 		ret |= int(b & 0x7f)
 		if b&0x80 == 0 {
 			*out = ret
@@ -545,7 +567,7 @@ func (s *String) ReadASN1BitString(out *encoding_asn1.BitString) bool {
 	return true
 }
 
-// ReadASN1BitString decodes an ASN.1 BIT STRING into out and advances. It is
+// ReadASN1BitStringAsBytes decodes an ASN.1 BIT STRING into out and advances. It is
 // an error if the BIT STRING is not a whole number of bytes. It reports
 // whether the read was successful.
 func (s *String) ReadASN1BitStringAsBytes(out *[]byte) bool {
@@ -654,34 +676,27 @@ func (s *String) SkipOptionalASN1(tag asn1.Tag) bool {
 	return s.ReadASN1(&unused, tag)
 }
 
-// ReadOptionalASN1Integer attempts to read an optional ASN.1 INTEGER
-// explicitly tagged with tag into out and advances. If no element with a
-// matching tag is present, it writes defaultValue into out instead. If out
-// does not point to an integer or to a big.Int, it panics. It reports
-// whether the read was successful.
+// ReadOptionalASN1Integer attempts to read an optional ASN.1 INTEGER explicitly
+// tagged with tag into out and advances. If no element with a matching tag is
+// present, it writes defaultValue into out instead. Otherwise, it behaves like
+// ReadASN1Integer.
 func (s *String) ReadOptionalASN1Integer(out interface{}, tag asn1.Tag, defaultValue interface{}) bool {
-	if reflect.TypeOf(out).Kind() != reflect.Ptr {
-		panic("out is not a pointer")
-	}
 	var present bool
 	var i String
 	if !s.ReadOptionalASN1(&i, &present, tag) {
 		return false
 	}
 	if !present {
-		switch reflect.ValueOf(out).Elem().Kind() {
-		case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64,
-			reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
+		switch out.(type) {
+		case *int, *int8, *int16, *int32, *int64,
+			*uint, *uint8, *uint16, *uint32, *uint64, *[]byte:
 			reflect.ValueOf(out).Elem().Set(reflect.ValueOf(defaultValue))
-		case reflect.Struct:
-			if reflect.TypeOf(out).Elem() != bigIntType {
-				panic("invalid integer type")
-			}
-			if reflect.TypeOf(defaultValue).Kind() != reflect.Ptr ||
-				reflect.TypeOf(defaultValue).Elem() != bigIntType {
+		case *big.Int:
+			if defaultValue, ok := defaultValue.(*big.Int); ok {
+				out.(*big.Int).Set(defaultValue)
+			} else {
 				panic("out points to big.Int, but defaultValue does not")
 			}
-			out.(*big.Int).Set(defaultValue.(*big.Int))
 		default:
 			panic("invalid integer type")
 		}
@@ -718,13 +733,14 @@ func (s *String) ReadOptionalASN1OctetString(out *[]byte, outPresent *bool, tag
 	return true
 }
 
-// ReadOptionalASN1Boolean sets *out to the value of the next ASN.1 BOOLEAN or,
-// if the next bytes are not an ASN.1 BOOLEAN, to the value of defaultValue.
-// It reports whether the operation was successful.
-func (s *String) ReadOptionalASN1Boolean(out *bool, defaultValue bool) bool {
+// ReadOptionalASN1Boolean attempts to read an optional ASN.1 BOOLEAN
+// explicitly tagged with tag into out and advances. If no element with a
+// matching tag is present, it sets "out" to defaultValue instead. It reports
+// whether the read was successful.
+func (s *String) ReadOptionalASN1Boolean(out *bool, tag asn1.Tag, defaultValue bool) bool {
 	var present bool
 	var child String
-	if !s.ReadOptionalASN1(&child, &present, asn1.BOOLEAN) {
+	if !s.ReadOptionalASN1(&child, &present, tag) {
 		return false
 	}
 
@@ -733,7 +749,7 @@ func (s *String) ReadOptionalASN1Boolean(out *bool, defaultValue bool) bool {
 		return true
 	}
 
-	return s.ReadASN1Boolean(out)
+	return child.ReadASN1Boolean(out)
 }
 
 func (s *String) readASN1(out *String, outTag *asn1.Tag, skipHeader bool) bool {

cryptobyte/asn1/asn1.go

@@ -4,7 +4,7 @@
 
 // Package asn1 contains supporting types for parsing and building ASN.1
 // messages with the cryptobyte package.
-package asn1 // import "golang.org/x/crypto/cryptobyte/asn1"
+package asn1
 
 // Tag represents an ASN.1 identifier octet, consisting of a tag number
 // (indicating a type) and class (such as context-specific or constructed).

cryptobyte/asn1_test.go

@@ -115,6 +115,28 @@ func TestReadASN1OptionalInteger(t *testing.T) {
 	}
 }
 
+const defaultBool = false
+
+var optionalBoolTestData = []readASN1Test{
+	{"empty", []byte{}, 0xa0, true, false},
+	{"invalid", []byte{0xa1, 0x3, 0x1, 0x2, 0x7f}, 0xa1, false, defaultBool},
+	{"missing", []byte{0xa1, 0x3, 0x1, 0x1, 0x7f}, 0xa0, true, defaultBool},
+	{"present", []byte{0xa1, 0x3, 0x1, 0x1, 0xff}, 0xa1, true, true},
+}
+
+func TestReadASN1OptionalBoolean(t *testing.T) {
+	for _, test := range optionalBoolTestData {
+		t.Run(test.name, func(t *testing.T) {
+			in := String(test.in)
+			var out bool
+			ok := in.ReadOptionalASN1Boolean(&out, test.tag, defaultBool)
+			if ok != test.ok || ok && out != test.out.(bool) {
+				t.Errorf("in.ReadOptionalASN1Boolean() = %v, want %v; out = %v, want %v", ok, test.ok, out, test.out)
+			}
+		})
+	}
+}
+
 func TestReadASN1IntegerSigned(t *testing.T) {
 	testData64 := []struct {
 		in  []byte
@@ -154,6 +176,32 @@ func TestReadASN1IntegerSigned(t *testing.T) {
 		}
 	})
 
+	// Repeat the same cases, reading into a []byte.
+	t.Run("bytes", func(t *testing.T) {
+		for i, test := range testData64 {
+			in := String(test.in)
+			var out []byte
+			ok := in.ReadASN1Integer(&out)
+			if test.out < 0 {
+				if ok {
+					t.Errorf("#%d: in.ReadASN1Integer(%d) = %v, want false", i, test.out, ok)
+				}
+				continue
+			}
+			if !ok {
+				t.Errorf("#%d: in.ReadASN1Integer() = %v, want true", i, ok)
+				continue
+			}
+			n := new(big.Int).SetBytes(out).Int64()
+			if n != test.out {
+				t.Errorf("#%d: in.ReadASN1Integer() = %v, want true; out = %x, want %d", i, ok, out, test.out)
+			}
+			if out[0] == 0 && len(out) > 1 {
+				t.Errorf("#%d: in.ReadASN1Integer() = %v; out = %x, has leading zeroes", i, ok, out)
+			}
+		}
+	})
+
 	// Repeat with the implicit-tagging functions
 	t.Run("WithTag", func(t *testing.T) {
 		for i, test := range testData64 {
@@ -250,6 +298,7 @@ func TestASN1ObjectIdentifier(t *testing.T) {
 		{[]byte{6, 7, 85, 0x02, 0x85, 0xc7, 0xcc, 0xfb, 0x01}, true, []int{2, 5, 2, 1492336001}},
 		{[]byte{6, 7, 0x55, 0x02, 0x87, 0xff, 0xff, 0xff, 0x7f}, true, []int{2, 5, 2, 2147483647}}, // 2**31-1
 		{[]byte{6, 7, 0x55, 0x02, 0x88, 0x80, 0x80, 0x80, 0x00}, false, []int{}},                   // 2**31
+		{[]byte{6, 3, 85, 0x80, 0x02}, false, []int{}},                                             // leading 0x80 octet
 	}
 
 	for i, test := range testData {

cryptobyte/builder.go

@@ -95,6 +95,11 @@ func (b *Builder) AddUint32(v uint32) {
 	b.add(byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
 }
 
+// AddUint48 appends a big-endian, 48-bit value to the byte string.
+func (b *Builder) AddUint48(v uint64) {
+	b.add(byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
+}
+
 // AddUint64 appends a big-endian, 64-bit value to the byte string.
 func (b *Builder) AddUint64(v uint64) {
 	b.add(byte(v>>56), byte(v>>48), byte(v>>40), byte(v>>32), byte(v>>24), byte(v>>16), byte(v>>8), byte(v))
@@ -303,9 +308,9 @@ func (b *Builder) add(bytes ...byte) {
 	b.result = append(b.result, bytes...)
 }
 
-// Unwrite rolls back n bytes written directly to the Builder. An attempt by a
-// child builder passed to a continuation to unwrite bytes from its parent will
-// panic.
+// Unwrite rolls back non-negative n bytes written directly to the Builder.
+// An attempt by a child builder passed to a continuation to unwrite bytes
+// from its parent will panic.
 func (b *Builder) Unwrite(n int) {
 	if b.err != nil {
 		return
@@ -317,6 +322,9 @@ func (b *Builder) Unwrite(n int) {
 	if length < 0 {
 		panic("cryptobyte: internal error")
 	}
+	if n < 0 {
+		panic("cryptobyte: attempted to unwrite negative number of bytes")
+	}
 	if n > length {
 		panic("cryptobyte: attempted to unwrite more than was written")
 	}

cryptobyte/cryptobyte_test.go

@@ -179,6 +179,27 @@ func TestUint32(t *testing.T) {
 	}
 }
 
+func TestUint48(t *testing.T) {
+	var b Builder
+	var u uint64 = 0xfefcff3cfdfc
+	b.AddUint48(u)
+	if err := builderBytesEq(&b, 254, 252, 255, 60, 253, 252); err != nil {
+		t.Error(err)
+	}
+
+	var s String = b.BytesOrPanic()
+	var v uint64
+	if !s.ReadUint48(&v) {
+		t.Error("ReadUint48() = false, want true")
+	}
+	if v != u {
+		t.Errorf("v = %x, want %x", v, u)
+	}
+	if len(s) != 0 {
+		t.Errorf("len(s) = %d, want 0", len(s))
+	}
+}
+
 func TestUint64(t *testing.T) {
 	var b Builder
 	b.AddUint64(0xf2fefefcff3cfdfc)

cryptobyte/string.go

@@ -15,7 +15,7 @@
 //
 // See the documentation and examples for the Builder and String types to get
 // started.
-package cryptobyte // import "golang.org/x/crypto/cryptobyte"
+package cryptobyte
 
 // String represents a string of bytes. It provides methods for parsing
 // fixed-length and length-prefixed values from it.
@@ -81,6 +81,17 @@ func (s *String) ReadUint32(out *uint32) bool {
 	return true
 }
 
+// ReadUint48 decodes a big-endian, 48-bit value into out and advances over it.
+// It reports whether the read was successful.
+func (s *String) ReadUint48(out *uint64) bool {
+	v := s.read(6)
+	if v == nil {
+		return false
+	}
+	*out = uint64(v[0])<<40 | uint64(v[1])<<32 | uint64(v[2])<<24 | uint64(v[3])<<16 | uint64(v[4])<<8 | uint64(v[5])
+	return true
+}
+
 // ReadUint64 decodes a big-endian, 64-bit value into out and advances over it.
 // It reports whether the read was successful.
 func (s *String) ReadUint64(out *uint64) bool {

curve25519/curve25519.go

@@ -5,15 +5,12 @@
 // Package curve25519 provides an implementation of the X25519 function, which
 // performs scalar multiplication on the elliptic curve known as Curve25519.
 // See RFC 7748.
-package curve25519 // import "golang.org/x/crypto/curve25519"
+//
+// This package is a wrapper for the X25519 implementation
+// in the crypto/ecdh package.
+package curve25519
 
-import (
-	"crypto/subtle"
-	"errors"
-	"strconv"
-
-	"golang.org/x/crypto/curve25519/internal/field"
-)
+import "crypto/ecdh"
 
 // ScalarMult sets dst to the product scalar * point.
 //
@@ -21,55 +18,13 @@ import (
 // zeroes, irrespective of the scalar. Instead, use the X25519 function, which
 // will return an error.
 func ScalarMult(dst, scalar, point *[32]byte) {
-	var e [32]byte
-
-	copy(e[:], scalar[:])
-	e[0] &= 248
-	e[31] &= 127
-	e[31] |= 64
-
-	var x1, x2, z2, x3, z3, tmp0, tmp1 field.Element
-	x1.SetBytes(point[:])
-	x2.One()
-	x3.Set(&x1)
-	z3.One()
-
-	swap := 0
-	for pos := 254; pos >= 0; pos-- {
-		b := e[pos/8] >> uint(pos&7)
-		b &= 1
-		swap ^= int(b)
-		x2.Swap(&x3, swap)
-		z2.Swap(&z3, swap)
-		swap = int(b)
-
-		tmp0.Subtract(&x3, &z3)
-		tmp1.Subtract(&x2, &z2)
-		x2.Add(&x2, &z2)
-		z2.Add(&x3, &z3)
-		z3.Multiply(&tmp0, &x2)
-		z2.Multiply(&z2, &tmp1)
-		tmp0.Square(&tmp1)
-		tmp1.Square(&x2)
-		x3.Add(&z3, &z2)
-		z2.Subtract(&z3, &z2)
-		x2.Multiply(&tmp1, &tmp0)
-		tmp1.Subtract(&tmp1, &tmp0)
-		z2.Square(&z2)
-
-		z3.Mult32(&tmp1, 121666)
-		x3.Square(&x3)
-		tmp0.Add(&tmp0, &z3)
-		z3.Multiply(&x1, &z2)
-		z2.Multiply(&tmp1, &tmp0)
+	if _, err := x25519(dst, scalar[:], point[:]); err != nil {
+		// The only error condition for x25519 when the inputs are 32 bytes long
+		// is if the output would have been the all-zero value.
+		for i := range dst {
+			dst[i] = 0
+		}
 	}
-
-	x2.Swap(&x3, swap)
-	z2.Swap(&z3, swap)
-
-	z2.Invert(&z2)
-	x2.Multiply(&x2, &z2)
-	copy(dst[:], x2.Bytes())
 }
 
 // ScalarBaseMult sets dst to the product scalar * base where base is the
@@ -78,7 +33,12 @@ func ScalarMult(dst, scalar, point *[32]byte) {
 // It is recommended to use the X25519 function with Basepoint instead, as
 // copying into fixed size arrays can lead to unexpected bugs.
 func ScalarBaseMult(dst, scalar *[32]byte) {
-	ScalarMult(dst, scalar, &basePoint)
+	curve := ecdh.X25519()
+	priv, err := curve.NewPrivateKey(scalar[:])
+	if err != nil {
+		panic("curve25519: internal error: scalarBaseMult was not 32 bytes")
+	}
+	copy(dst[:], priv.PublicKey().Bytes())
 }
 
 const (
@@ -91,21 +51,10 @@ const (
 // 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}
+var basePoint = [32]byte{9}
 
 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")
-	}
-}
-
 // X25519 returns the result of the scalar multiplication (scalar * point),
 // according to RFC 7748, Section 5. scalar, point and the return value are
 // slices of 32 bytes.
@@ -123,24 +72,19 @@ func X25519(scalar, point []byte) ([]byte, error) {
 }
 
 func x25519(dst *[32]byte, scalar, point []byte) ([]byte, error) {
-	var in [32]byte
-	if l := len(scalar); l != 32 {
-		return nil, errors.New("bad scalar length: " + strconv.Itoa(l) + ", expected 32")
+	curve := ecdh.X25519()
+	pub, err := curve.NewPublicKey(point)
+	if err != nil {
+		return nil, err
 	}
-	if l := len(point); l != 32 {
-		return nil, errors.New("bad point length: " + strconv.Itoa(l) + ", expected 32")
+	priv, err := curve.NewPrivateKey(scalar)
+	if err != nil {
+		return nil, err
 	}
-	copy(in[:], scalar)
-	if &point[0] == &Basepoint[0] {
-		checkBasepoint()
-		ScalarBaseMult(dst, &in)
-	} else {
-		var base, zero [32]byte
-		copy(base[:], point)
-		ScalarMult(dst, &in, &base)
-		if subtle.ConstantTimeCompare(dst[:], zero[:]) == 1 {
-			return nil, errors.New("bad input point: low order point")
-		}
+	out, err := priv.ECDH(pub)
+	if err != nil {
+		return nil, err
 	}
+	copy(dst[:], out)
 	return dst[:], nil
 }

curve25519/curve25519_test.go

@@ -2,13 +2,15 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-package curve25519
+package curve25519_test
 
 import (
 	"bytes"
 	"crypto/rand"
 	"encoding/hex"
 	"testing"
+
+	"golang.org/x/crypto/curve25519"
 )
 
 const expectedHex = "89161fde887b2b53de549af483940106ecc114d6982daa98256de23bdf77661a"
@@ -19,7 +21,7 @@ func TestX25519Basepoint(t *testing.T) {
 
 	for i := 0; i < 200; i++ {
 		var err error
-		x, err = X25519(x, Basepoint)
+		x, err = curve25519.X25519(x, curve25519.Basepoint)
 		if err != nil {
 			t.Fatal(err)
 		}
@@ -32,12 +34,12 @@ func TestX25519Basepoint(t *testing.T) {
 }
 
 func TestLowOrderPoints(t *testing.T) {
-	scalar := make([]byte, ScalarSize)
+	scalar := make([]byte, curve25519.ScalarSize)
 	if _, err := rand.Read(scalar); err != nil {
 		t.Fatal(err)
 	}
 	for i, p := range lowOrderPoints {
-		out, err := X25519(scalar, p)
+		out, err := curve25519.X25519(scalar, p)
 		if err == nil {
 			t.Errorf("%d: expected error, got nil", i)
 		}
@@ -48,10 +50,10 @@ func TestLowOrderPoints(t *testing.T) {
 }
 
 func TestTestVectors(t *testing.T) {
-	t.Run("Legacy", func(t *testing.T) { testTestVectors(t, ScalarMult) })
+	t.Run("Legacy", func(t *testing.T) { testTestVectors(t, curve25519.ScalarMult) })
 	t.Run("X25519", func(t *testing.T) {
 		testTestVectors(t, func(dst, scalar, point *[32]byte) {
-			out, err := X25519(scalar[:], point[:])
+			out, err := curve25519.X25519(scalar[:], point[:])
 			if err != nil {
 				t.Fatal(err)
 			}
@@ -88,10 +90,10 @@ func TestHighBitIgnored(t *testing.T) {
 	var hi0, hi1 [32]byte
 
 	u[31] &= 0x7f
-	ScalarMult(&hi0, &s, &u)
+	curve25519.ScalarMult(&hi0, &s, &u)
 
 	u[31] |= 0x80
-	ScalarMult(&hi1, &s, &u)
+	curve25519.ScalarMult(&hi1, &s, &u)
 
 	if !bytes.Equal(hi0[:], hi1[:]) {
 		t.Errorf("high bit of group point should not affect result")
@@ -101,14 +103,14 @@ func TestHighBitIgnored(t *testing.T) {
 var benchmarkSink byte
 
 func BenchmarkX25519Basepoint(b *testing.B) {
-	scalar := make([]byte, ScalarSize)
+	scalar := make([]byte, curve25519.ScalarSize)
 	if _, err := rand.Read(scalar); err != nil {
 		b.Fatal(err)
 	}
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		out, err := X25519(scalar, Basepoint)
+		out, err := curve25519.X25519(scalar, curve25519.Basepoint)
 		if err != nil {
 			b.Fatal(err)
 		}
@@ -117,11 +119,11 @@ func BenchmarkX25519Basepoint(b *testing.B) {
 }
 
 func BenchmarkX25519(b *testing.B) {
-	scalar := make([]byte, ScalarSize)
+	scalar := make([]byte, curve25519.ScalarSize)
 	if _, err := rand.Read(scalar); err != nil {
 		b.Fatal(err)
 	}
-	point, err := X25519(scalar, Basepoint)
+	point, err := curve25519.X25519(scalar, curve25519.Basepoint)
 	if err != nil {
 		b.Fatal(err)
 	}
@@ -131,7 +133,7 @@ func BenchmarkX25519(b *testing.B) {
 
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		out, err := X25519(scalar, point)
+		out, err := curve25519.X25519(scalar, point)
 		if err != nil {
 			b.Fatal(err)
 		}

curve25519/internal/field/README

@@ -1,7 +0,0 @@
-This package is kept in sync with crypto/ed25519/internal/edwards25519/field in
-the standard library.
-
-If there are any changes in the standard library that need to be synced to this
-package, run sync.sh. It will not overwrite any local changes made since the
-previous sync, so it's ok to land changes in this package first, and then sync
-to the standard library later.

curve25519/internal/field/_asm/fe_amd64_asm.go

@@ -1,298 +0,0 @@
-// Copyright (c) 2021 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 main
-
-import (
-	"fmt"
-
-	. "github.com/mmcloughlin/avo/build"
-	. "github.com/mmcloughlin/avo/gotypes"
-	. "github.com/mmcloughlin/avo/operand"
-	. "github.com/mmcloughlin/avo/reg"
-
-	// Ensure "go mod tidy" doesn't remove the golang.org/x/crypto module
-	// dependency, which is necessary to access the field.Element type.
-	_ "golang.org/x/crypto/curve25519"
-)
-
-//go:generate go run . -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field
-
-func main() {
-	Package("golang.org/x/crypto/curve25519/internal/field")
-	ConstraintExpr("amd64,gc,!purego")
-	feMul()
-	feSquare()
-	Generate()
-}
-
-type namedComponent struct {
-	Component
-	name string
-}
-
-func (c namedComponent) String() string { return c.name }
-
-type uint128 struct {
-	name   string
-	hi, lo GPVirtual
-}
-
-func (c uint128) String() string { return c.name }
-
-func feSquare() {
-	TEXT("feSquare", NOSPLIT, "func(out, a *Element)")
-	Doc("feSquare sets out = a * a. It works like feSquareGeneric.")
-	Pragma("noescape")
-
-	a := Dereference(Param("a"))
-	l0 := namedComponent{a.Field("l0"), "l0"}
-	l1 := namedComponent{a.Field("l1"), "l1"}
-	l2 := namedComponent{a.Field("l2"), "l2"}
-	l3 := namedComponent{a.Field("l3"), "l3"}
-	l4 := namedComponent{a.Field("l4"), "l4"}
-
-	// r0 = l0×l0 + 19×2×(l1×l4 + l2×l3)
-	r0 := uint128{"r0", GP64(), GP64()}
-	mul64(r0, 1, l0, l0)
-	addMul64(r0, 38, l1, l4)
-	addMul64(r0, 38, l2, l3)
-
-	// r1 = 2×l0×l1 + 19×2×l2×l4 + 19×l3×l3
-	r1 := uint128{"r1", GP64(), GP64()}
-	mul64(r1, 2, l0, l1)
-	addMul64(r1, 38, l2, l4)
-	addMul64(r1, 19, l3, l3)
-
-	// r2 = = 2×l0×l2 + l1×l1 + 19×2×l3×l4
-	r2 := uint128{"r2", GP64(), GP64()}
-	mul64(r2, 2, l0, l2)
-	addMul64(r2, 1, l1, l1)
-	addMul64(r2, 38, l3, l4)
-
-	// r3 = = 2×l0×l3 + 2×l1×l2 + 19×l4×l4
-	r3 := uint128{"r3", GP64(), GP64()}
-	mul64(r3, 2, l0, l3)
-	addMul64(r3, 2, l1, l2)
-	addMul64(r3, 19, l4, l4)
-
-	// r4 = = 2×l0×l4 + 2×l1×l3 + l2×l2
-	r4 := uint128{"r4", GP64(), GP64()}
-	mul64(r4, 2, l0, l4)
-	addMul64(r4, 2, l1, l3)
-	addMul64(r4, 1, l2, l2)
-
-	Comment("First reduction chain")
-	maskLow51Bits := GP64()
-	MOVQ(Imm((1<<51)-1), maskLow51Bits)
-	c0, r0lo := shiftRightBy51(&r0)
-	c1, r1lo := shiftRightBy51(&r1)
-	c2, r2lo := shiftRightBy51(&r2)
-	c3, r3lo := shiftRightBy51(&r3)
-	c4, r4lo := shiftRightBy51(&r4)
-	maskAndAdd(r0lo, maskLow51Bits, c4, 19)
-	maskAndAdd(r1lo, maskLow51Bits, c0, 1)
-	maskAndAdd(r2lo, maskLow51Bits, c1, 1)
-	maskAndAdd(r3lo, maskLow51Bits, c2, 1)
-	maskAndAdd(r4lo, maskLow51Bits, c3, 1)
-
-	Comment("Second reduction chain (carryPropagate)")
-	// c0 = r0 >> 51
-	MOVQ(r0lo, c0)
-	SHRQ(Imm(51), c0)
-	// c1 = r1 >> 51
-	MOVQ(r1lo, c1)
-	SHRQ(Imm(51), c1)
-	// c2 = r2 >> 51
-	MOVQ(r2lo, c2)
-	SHRQ(Imm(51), c2)
-	// c3 = r3 >> 51
-	MOVQ(r3lo, c3)
-	SHRQ(Imm(51), c3)
-	// c4 = r4 >> 51
-	MOVQ(r4lo, c4)
-	SHRQ(Imm(51), c4)
-	maskAndAdd(r0lo, maskLow51Bits, c4, 19)
-	maskAndAdd(r1lo, maskLow51Bits, c0, 1)
-	maskAndAdd(r2lo, maskLow51Bits, c1, 1)
-	maskAndAdd(r3lo, maskLow51Bits, c2, 1)
-	maskAndAdd(r4lo, maskLow51Bits, c3, 1)
-
-	Comment("Store output")
-	out := Dereference(Param("out"))
-	Store(r0lo, out.Field("l0"))
-	Store(r1lo, out.Field("l1"))
-	Store(r2lo, out.Field("l2"))
-	Store(r3lo, out.Field("l3"))
-	Store(r4lo, out.Field("l4"))
-
-	RET()
-}
-
-func feMul() {
-	TEXT("feMul", NOSPLIT, "func(out, a, b *Element)")
-	Doc("feMul sets out = a * b. It works like feMulGeneric.")
-	Pragma("noescape")
-
-	a := Dereference(Param("a"))
-	a0 := namedComponent{a.Field("l0"), "a0"}
-	a1 := namedComponent{a.Field("l1"), "a1"}
-	a2 := namedComponent{a.Field("l2"), "a2"}
-	a3 := namedComponent{a.Field("l3"), "a3"}
-	a4 := namedComponent{a.Field("l4"), "a4"}
-
-	b := Dereference(Param("b"))
-	b0 := namedComponent{b.Field("l0"), "b0"}
-	b1 := namedComponent{b.Field("l1"), "b1"}
-	b2 := namedComponent{b.Field("l2"), "b2"}
-	b3 := namedComponent{b.Field("l3"), "b3"}
-	b4 := namedComponent{b.Field("l4"), "b4"}
-
-	// r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
-	r0 := uint128{"r0", GP64(), GP64()}
-	mul64(r0, 1, a0, b0)
-	addMul64(r0, 19, a1, b4)
-	addMul64(r0, 19, a2, b3)
-	addMul64(r0, 19, a3, b2)
-	addMul64(r0, 19, a4, b1)
-
-	// r1 = a0×b1 + a1×b0 + 19×(a2×b4 + a3×b3 + a4×b2)
-	r1 := uint128{"r1", GP64(), GP64()}
-	mul64(r1, 1, a0, b1)
-	addMul64(r1, 1, a1, b0)
-	addMul64(r1, 19, a2, b4)
-	addMul64(r1, 19, a3, b3)
-	addMul64(r1, 19, a4, b2)
-
-	// r2 = a0×b2 + a1×b1 + a2×b0 + 19×(a3×b4 + a4×b3)
-	r2 := uint128{"r2", GP64(), GP64()}
-	mul64(r2, 1, a0, b2)
-	addMul64(r2, 1, a1, b1)
-	addMul64(r2, 1, a2, b0)
-	addMul64(r2, 19, a3, b4)
-	addMul64(r2, 19, a4, b3)
-
-	// r3 = a0×b3 + a1×b2 + a2×b1 + a3×b0 + 19×a4×b4
-	r3 := uint128{"r3", GP64(), GP64()}
-	mul64(r3, 1, a0, b3)
-	addMul64(r3, 1, a1, b2)
-	addMul64(r3, 1, a2, b1)
-	addMul64(r3, 1, a3, b0)
-	addMul64(r3, 19, a4, b4)
-
-	// r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
-	r4 := uint128{"r4", GP64(), GP64()}
-	mul64(r4, 1, a0, b4)
-	addMul64(r4, 1, a1, b3)
-	addMul64(r4, 1, a2, b2)
-	addMul64(r4, 1, a3, b1)
-	addMul64(r4, 1, a4, b0)
-
-	Comment("First reduction chain")
-	maskLow51Bits := GP64()
-	MOVQ(Imm((1<<51)-1), maskLow51Bits)
-	c0, r0lo := shiftRightBy51(&r0)
-	c1, r1lo := shiftRightBy51(&r1)
-	c2, r2lo := shiftRightBy51(&r2)
-	c3, r3lo := shiftRightBy51(&r3)
-	c4, r4lo := shiftRightBy51(&r4)
-	maskAndAdd(r0lo, maskLow51Bits, c4, 19)
-	maskAndAdd(r1lo, maskLow51Bits, c0, 1)
-	maskAndAdd(r2lo, maskLow51Bits, c1, 1)
-	maskAndAdd(r3lo, maskLow51Bits, c2, 1)
-	maskAndAdd(r4lo, maskLow51Bits, c3, 1)
-
-	Comment("Second reduction chain (carryPropagate)")
-	// c0 = r0 >> 51
-	MOVQ(r0lo, c0)
-	SHRQ(Imm(51), c0)
-	// c1 = r1 >> 51
-	MOVQ(r1lo, c1)
-	SHRQ(Imm(51), c1)
-	// c2 = r2 >> 51
-	MOVQ(r2lo, c2)
-	SHRQ(Imm(51), c2)
-	// c3 = r3 >> 51
-	MOVQ(r3lo, c3)
-	SHRQ(Imm(51), c3)
-	// c4 = r4 >> 51
-	MOVQ(r4lo, c4)
-	SHRQ(Imm(51), c4)
-	maskAndAdd(r0lo, maskLow51Bits, c4, 19)
-	maskAndAdd(r1lo, maskLow51Bits, c0, 1)
-	maskAndAdd(r2lo, maskLow51Bits, c1, 1)
-	maskAndAdd(r3lo, maskLow51Bits, c2, 1)
-	maskAndAdd(r4lo, maskLow51Bits, c3, 1)
-
-	Comment("Store output")
-	out := Dereference(Param("out"))
-	Store(r0lo, out.Field("l0"))
-	Store(r1lo, out.Field("l1"))
-	Store(r2lo, out.Field("l2"))
-	Store(r3lo, out.Field("l3"))
-	Store(r4lo, out.Field("l4"))
-
-	RET()
-}
-
-// mul64 sets r to i * aX * bX.
-func mul64(r uint128, i int, aX, bX namedComponent) {
-	switch i {
-	case 1:
-		Comment(fmt.Sprintf("%s = %s×%s", r, aX, bX))
-		Load(aX, RAX)
-	case 2:
-		Comment(fmt.Sprintf("%s = 2×%s×%s", r, aX, bX))
-		Load(aX, RAX)
-		SHLQ(Imm(1), RAX)
-	default:
-		panic("unsupported i value")
-	}
-	MULQ(mustAddr(bX)) // RDX, RAX = RAX * bX
-	MOVQ(RAX, r.lo)
-	MOVQ(RDX, r.hi)
-}
-
-// addMul64 sets r to r + i * aX * bX.
-func addMul64(r uint128, i uint64, aX, bX namedComponent) {
-	switch i {
-	case 1:
-		Comment(fmt.Sprintf("%s += %s×%s", r, aX, bX))
-		Load(aX, RAX)
-	default:
-		Comment(fmt.Sprintf("%s += %d×%s×%s", r, i, aX, bX))
-		IMUL3Q(Imm(i), Load(aX, GP64()), RAX)
-	}
-	MULQ(mustAddr(bX)) // RDX, RAX = RAX * bX
-	ADDQ(RAX, r.lo)
-	ADCQ(RDX, r.hi)
-}
-
-// shiftRightBy51 returns r >> 51 and r.lo.
-//
-// After this function is called, the uint128 may not be used anymore.
-func shiftRightBy51(r *uint128) (out, lo GPVirtual) {
-	out = r.hi
-	lo = r.lo
-	SHLQ(Imm(64-51), r.lo, r.hi)
-	r.lo, r.hi = nil, nil // make sure the uint128 is unusable
-	return
-}
-
-// maskAndAdd sets r = r&mask + c*i.
-func maskAndAdd(r, mask, c GPVirtual, i uint64) {
-	ANDQ(mask, r)
-	if i != 1 {
-		IMUL3Q(Imm(i), c, c)
-	}
-	ADDQ(c, r)
-}
-
-func mustAddr(c Component) Op {
-	b, err := c.Resolve()
-	if err != nil {
-		panic(err)
-	}
-	return b.Addr
-}

curve25519/internal/field/_asm/go.mod

@@ -1,10 +0,0 @@
-module asm
-
-go 1.16
-
-require (
-	github.com/mmcloughlin/avo v0.4.0
-	golang.org/x/crypto v0.0.0
-)
-
-replace golang.org/x/crypto v0.0.0 => ../../../..

curve25519/internal/field/_asm/go.sum

@@ -1,34 +0,0 @@
-github.com/mmcloughlin/avo v0.4.0 h1:jeHDRktVD+578ULxWpQHkilor6pkdLF7u7EiTzDbfcU=
-github.com/mmcloughlin/avo v0.4.0/go.mod h1:RW9BfYA3TgO9uCdNrKU2h6J8cPD8ZLznvfgHAeszb1s=
-github.com/yuin/goldmark v1.4.0/go.mod h1:mwnBkeHKe2W/ZEtQ+71ViKU8L12m81fl3OWwC1Zlc8k=
-golang.org/x/arch v0.0.0-20210923205945-b76863e36670/go.mod h1:5om86z9Hs0C8fWVUuoMHwpExlXzs5Tkyp9hOrfG7pp8=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
-golang.org/x/mod v0.4.2 h1:Gz96sIWK3OalVv/I/qNygP42zyoKp3xptRVCWRFEBvo=
-golang.org/x/mod v0.4.2/go.mod h1:s0Qsj1ACt9ePp/hMypM3fl4fZqREWJwdYDEqhRiZZUA=
-golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
-golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20210805182204-aaa1db679c0d/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20210220032951-036812b2e83c/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210423082822-04245dca01da/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20210809222454-d867a43fc93e/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20211030160813-b3129d9d1021 h1:giLT+HuUP/gXYrG2Plg9WTjj4qhfgaW424ZIFog3rlk=
-golang.org/x/sys v0.0.0-20211030160813-b3129d9d1021/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.6/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.1.7 h1:6j8CgantCy3yc8JGBqkDLMKWqZ0RDU2g1HVgacojGWQ=
-golang.org/x/tools v0.1.7/go.mod h1:LGqMHiF4EqQNHR1JncWGqT5BVaXmza+X+BDGol+dOxo=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20191011141410-1b5146add898/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1 h1:go1bK/D/BFZV2I8cIQd1NKEZ+0owSTG1fDTci4IqFcE=
-golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
-rsc.io/pdf v0.1.1/go.mod h1:n8OzWcQ6Sp37PL01nO98y4iUCRdTGarVfzxY20ICaU4=

curve25519/internal/field/fe.go

@@ -1,416 +0,0 @@
-// Copyright (c) 2017 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 field implements fast arithmetic modulo 2^255-19.
-package field
-
-import (
-	"crypto/subtle"
-	"encoding/binary"
-	"math/bits"
-)
-
-// Element represents an element of the field GF(2^255-19). Note that this
-// is not a cryptographically secure group, and should only be used to interact
-// with edwards25519.Point coordinates.
-//
-// This type works similarly to math/big.Int, and all arguments and receivers
-// are allowed to alias.
-//
-// The zero value is a valid zero element.
-type Element struct {
-	// An element t represents the integer
-	//     t.l0 + t.l1*2^51 + t.l2*2^102 + t.l3*2^153 + t.l4*2^204
-	//
-	// Between operations, all limbs are expected to be lower than 2^52.
-	l0 uint64
-	l1 uint64
-	l2 uint64
-	l3 uint64
-	l4 uint64
-}
-
-const maskLow51Bits uint64 = (1 << 51) - 1
-
-var feZero = &Element{0, 0, 0, 0, 0}
-
-// Zero sets v = 0, and returns v.
-func (v *Element) Zero() *Element {
-	*v = *feZero
-	return v
-}
-
-var feOne = &Element{1, 0, 0, 0, 0}
-
-// One sets v = 1, and returns v.
-func (v *Element) One() *Element {
-	*v = *feOne
-	return v
-}
-
-// reduce reduces v modulo 2^255 - 19 and returns it.
-func (v *Element) reduce() *Element {
-	v.carryPropagate()
-
-	// After the light reduction we now have a field element representation
-	// v < 2^255 + 2^13 * 19, but need v < 2^255 - 19.
-
-	// If v >= 2^255 - 19, then v + 19 >= 2^255, which would overflow 2^255 - 1,
-	// generating a carry. That is, c will be 0 if v < 2^255 - 19, and 1 otherwise.
-	c := (v.l0 + 19) >> 51
-	c = (v.l1 + c) >> 51
-	c = (v.l2 + c) >> 51
-	c = (v.l3 + c) >> 51
-	c = (v.l4 + c) >> 51
-
-	// If v < 2^255 - 19 and c = 0, this will be a no-op. Otherwise, it's
-	// effectively applying the reduction identity to the carry.
-	v.l0 += 19 * c
-
-	v.l1 += v.l0 >> 51
-	v.l0 = v.l0 & maskLow51Bits
-	v.l2 += v.l1 >> 51
-	v.l1 = v.l1 & maskLow51Bits
-	v.l3 += v.l2 >> 51
-	v.l2 = v.l2 & maskLow51Bits
-	v.l4 += v.l3 >> 51
-	v.l3 = v.l3 & maskLow51Bits
-	// no additional carry
-	v.l4 = v.l4 & maskLow51Bits
-
-	return v
-}
-
-// Add sets v = a + b, and returns v.
-func (v *Element) Add(a, b *Element) *Element {
-	v.l0 = a.l0 + b.l0
-	v.l1 = a.l1 + b.l1
-	v.l2 = a.l2 + b.l2
-	v.l3 = a.l3 + b.l3
-	v.l4 = a.l4 + b.l4
-	// Using the generic implementation here is actually faster than the
-	// assembly. Probably because the body of this function is so simple that
-	// the compiler can figure out better optimizations by inlining the carry
-	// propagation. TODO
-	return v.carryPropagateGeneric()
-}
-
-// Subtract sets v = a - b, and returns v.
-func (v *Element) Subtract(a, b *Element) *Element {
-	// We first add 2 * p, to guarantee the subtraction won't underflow, and
-	// then subtract b (which can be up to 2^255 + 2^13 * 19).
-	v.l0 = (a.l0 + 0xFFFFFFFFFFFDA) - b.l0
-	v.l1 = (a.l1 + 0xFFFFFFFFFFFFE) - b.l1
-	v.l2 = (a.l2 + 0xFFFFFFFFFFFFE) - b.l2
-	v.l3 = (a.l3 + 0xFFFFFFFFFFFFE) - b.l3
-	v.l4 = (a.l4 + 0xFFFFFFFFFFFFE) - b.l4
-	return v.carryPropagate()
-}
-
-// Negate sets v = -a, and returns v.
-func (v *Element) Negate(a *Element) *Element {
-	return v.Subtract(feZero, a)
-}
-
-// Invert sets v = 1/z mod p, and returns v.
-//
-// If z == 0, Invert returns v = 0.
-func (v *Element) Invert(z *Element) *Element {
-	// Inversion is implemented as exponentiation with exponent p − 2. It uses the
-	// same sequence of 255 squarings and 11 multiplications as [Curve25519].
-	var z2, z9, z11, z2_5_0, z2_10_0, z2_20_0, z2_50_0, z2_100_0, t Element
-
-	z2.Square(z)             // 2
-	t.Square(&z2)            // 4
-	t.Square(&t)             // 8
-	z9.Multiply(&t, z)       // 9
-	z11.Multiply(&z9, &z2)   // 11
-	t.Square(&z11)           // 22
-	z2_5_0.Multiply(&t, &z9) // 31 = 2^5 - 2^0
-
-	t.Square(&z2_5_0) // 2^6 - 2^1
-	for i := 0; i < 4; i++ {
-		t.Square(&t) // 2^10 - 2^5
-	}
-	z2_10_0.Multiply(&t, &z2_5_0) // 2^10 - 2^0
-
-	t.Square(&z2_10_0) // 2^11 - 2^1
-	for i := 0; i < 9; i++ {
-		t.Square(&t) // 2^20 - 2^10
-	}
-	z2_20_0.Multiply(&t, &z2_10_0) // 2^20 - 2^0
-
-	t.Square(&z2_20_0) // 2^21 - 2^1
-	for i := 0; i < 19; i++ {
-		t.Square(&t) // 2^40 - 2^20
-	}
-	t.Multiply(&t, &z2_20_0) // 2^40 - 2^0
-
-	t.Square(&t) // 2^41 - 2^1
-	for i := 0; i < 9; i++ {
-		t.Square(&t) // 2^50 - 2^10
-	}
-	z2_50_0.Multiply(&t, &z2_10_0) // 2^50 - 2^0
-
-	t.Square(&z2_50_0) // 2^51 - 2^1
-	for i := 0; i < 49; i++ {
-		t.Square(&t) // 2^100 - 2^50
-	}
-	z2_100_0.Multiply(&t, &z2_50_0) // 2^100 - 2^0
-
-	t.Square(&z2_100_0) // 2^101 - 2^1
-	for i := 0; i < 99; i++ {
-		t.Square(&t) // 2^200 - 2^100
-	}
-	t.Multiply(&t, &z2_100_0) // 2^200 - 2^0
-
-	t.Square(&t) // 2^201 - 2^1
-	for i := 0; i < 49; i++ {
-		t.Square(&t) // 2^250 - 2^50
-	}
-	t.Multiply(&t, &z2_50_0) // 2^250 - 2^0
-
-	t.Square(&t) // 2^251 - 2^1
-	t.Square(&t) // 2^252 - 2^2
-	t.Square(&t) // 2^253 - 2^3
-	t.Square(&t) // 2^254 - 2^4
-	t.Square(&t) // 2^255 - 2^5
-
-	return v.Multiply(&t, &z11) // 2^255 - 21
-}
-
-// Set sets v = a, and returns v.
-func (v *Element) Set(a *Element) *Element {
-	*v = *a
-	return v
-}
-
-// SetBytes sets v to x, which must be a 32-byte little-endian encoding.
-//
-// Consistent with RFC 7748, the most significant bit (the high bit of the
-// last byte) is ignored, and non-canonical values (2^255-19 through 2^255-1)
-// are accepted. Note that this is laxer than specified by RFC 8032.
-func (v *Element) SetBytes(x []byte) *Element {
-	if len(x) != 32 {
-		panic("edwards25519: invalid field element input size")
-	}
-
-	// Bits 0:51 (bytes 0:8, bits 0:64, shift 0, mask 51).
-	v.l0 = binary.LittleEndian.Uint64(x[0:8])
-	v.l0 &= maskLow51Bits
-	// Bits 51:102 (bytes 6:14, bits 48:112, shift 3, mask 51).
-	v.l1 = binary.LittleEndian.Uint64(x[6:14]) >> 3
-	v.l1 &= maskLow51Bits
-	// Bits 102:153 (bytes 12:20, bits 96:160, shift 6, mask 51).
-	v.l2 = binary.LittleEndian.Uint64(x[12:20]) >> 6
-	v.l2 &= maskLow51Bits
-	// Bits 153:204 (bytes 19:27, bits 152:216, shift 1, mask 51).
-	v.l3 = binary.LittleEndian.Uint64(x[19:27]) >> 1
-	v.l3 &= maskLow51Bits
-	// Bits 204:251 (bytes 24:32, bits 192:256, shift 12, mask 51).
-	// Note: not bytes 25:33, shift 4, to avoid overread.
-	v.l4 = binary.LittleEndian.Uint64(x[24:32]) >> 12
-	v.l4 &= maskLow51Bits
-
-	return v
-}
-
-// Bytes returns the canonical 32-byte little-endian encoding of v.
-func (v *Element) Bytes() []byte {
-	// This function is outlined to make the allocations inline in the caller
-	// rather than happen on the heap.
-	var out [32]byte
-	return v.bytes(&out)
-}
-
-func (v *Element) bytes(out *[32]byte) []byte {
-	t := *v
-	t.reduce()
-
-	var buf [8]byte
-	for i, l := range [5]uint64{t.l0, t.l1, t.l2, t.l3, t.l4} {
-		bitsOffset := i * 51
-		binary.LittleEndian.PutUint64(buf[:], l<<uint(bitsOffset%8))
-		for i, bb := range buf {
-			off := bitsOffset/8 + i
-			if off >= len(out) {
-				break
-			}
-			out[off] |= bb
-		}
-	}
-
-	return out[:]
-}
-
-// Equal returns 1 if v and u are equal, and 0 otherwise.
-func (v *Element) Equal(u *Element) int {
-	sa, sv := u.Bytes(), v.Bytes()
-	return subtle.ConstantTimeCompare(sa, sv)
-}
-
-// mask64Bits returns 0xffffffff if cond is 1, and 0 otherwise.
-func mask64Bits(cond int) uint64 { return ^(uint64(cond) - 1) }
-
-// Select sets v to a if cond == 1, and to b if cond == 0.
-func (v *Element) Select(a, b *Element, cond int) *Element {
-	m := mask64Bits(cond)
-	v.l0 = (m & a.l0) | (^m & b.l0)
-	v.l1 = (m & a.l1) | (^m & b.l1)
-	v.l2 = (m & a.l2) | (^m & b.l2)
-	v.l3 = (m & a.l3) | (^m & b.l3)
-	v.l4 = (m & a.l4) | (^m & b.l4)
-	return v
-}
-
-// Swap swaps v and u if cond == 1 or leaves them unchanged if cond == 0, and returns v.
-func (v *Element) Swap(u *Element, cond int) {
-	m := mask64Bits(cond)
-	t := m & (v.l0 ^ u.l0)
-	v.l0 ^= t
-	u.l0 ^= t
-	t = m & (v.l1 ^ u.l1)
-	v.l1 ^= t
-	u.l1 ^= t
-	t = m & (v.l2 ^ u.l2)
-	v.l2 ^= t
-	u.l2 ^= t
-	t = m & (v.l3 ^ u.l3)
-	v.l3 ^= t
-	u.l3 ^= t
-	t = m & (v.l4 ^ u.l4)
-	v.l4 ^= t
-	u.l4 ^= t
-}
-
-// IsNegative returns 1 if v is negative, and 0 otherwise.
-func (v *Element) IsNegative() int {
-	return int(v.Bytes()[0] & 1)
-}
-
-// Absolute sets v to |u|, and returns v.
-func (v *Element) Absolute(u *Element) *Element {
-	return v.Select(new(Element).Negate(u), u, u.IsNegative())
-}
-
-// Multiply sets v = x * y, and returns v.
-func (v *Element) Multiply(x, y *Element) *Element {
-	feMul(v, x, y)
-	return v
-}
-
-// Square sets v = x * x, and returns v.
-func (v *Element) Square(x *Element) *Element {
-	feSquare(v, x)
-	return v
-}
-
-// Mult32 sets v = x * y, and returns v.
-func (v *Element) Mult32(x *Element, y uint32) *Element {
-	x0lo, x0hi := mul51(x.l0, y)
-	x1lo, x1hi := mul51(x.l1, y)
-	x2lo, x2hi := mul51(x.l2, y)
-	x3lo, x3hi := mul51(x.l3, y)
-	x4lo, x4hi := mul51(x.l4, y)
-	v.l0 = x0lo + 19*x4hi // carried over per the reduction identity
-	v.l1 = x1lo + x0hi
-	v.l2 = x2lo + x1hi
-	v.l3 = x3lo + x2hi
-	v.l4 = x4lo + x3hi
-	// The hi portions are going to be only 32 bits, plus any previous excess,
-	// so we can skip the carry propagation.
-	return v
-}
-
-// mul51 returns lo + hi * 2⁵¹ = a * b.
-func mul51(a uint64, b uint32) (lo uint64, hi uint64) {
-	mh, ml := bits.Mul64(a, uint64(b))
-	lo = ml & maskLow51Bits
-	hi = (mh << 13) | (ml >> 51)
-	return
-}
-
-// Pow22523 set v = x^((p-5)/8), and returns v. (p-5)/8 is 2^252-3.
-func (v *Element) Pow22523(x *Element) *Element {
-	var t0, t1, t2 Element
-
-	t0.Square(x)             // x^2
-	t1.Square(&t0)           // x^4
-	t1.Square(&t1)           // x^8
-	t1.Multiply(x, &t1)      // x^9
-	t0.Multiply(&t0, &t1)    // x^11
-	t0.Square(&t0)           // x^22
-	t0.Multiply(&t1, &t0)    // x^31
-	t1.Square(&t0)           // x^62
-	for i := 1; i < 5; i++ { // x^992
-		t1.Square(&t1)
-	}
-	t0.Multiply(&t1, &t0)     // x^1023 -> 1023 = 2^10 - 1
-	t1.Square(&t0)            // 2^11 - 2
-	for i := 1; i < 10; i++ { // 2^20 - 2^10
-		t1.Square(&t1)
-	}
-	t1.Multiply(&t1, &t0)     // 2^20 - 1
-	t2.Square(&t1)            // 2^21 - 2
-	for i := 1; i < 20; i++ { // 2^40 - 2^20
-		t2.Square(&t2)
-	}
-	t1.Multiply(&t2, &t1)     // 2^40 - 1
-	t1.Square(&t1)            // 2^41 - 2
-	for i := 1; i < 10; i++ { // 2^50 - 2^10
-		t1.Square(&t1)
-	}
-	t0.Multiply(&t1, &t0)     // 2^50 - 1
-	t1.Square(&t0)            // 2^51 - 2
-	for i := 1; i < 50; i++ { // 2^100 - 2^50
-		t1.Square(&t1)
-	}
-	t1.Multiply(&t1, &t0)      // 2^100 - 1
-	t2.Square(&t1)             // 2^101 - 2
-	for i := 1; i < 100; i++ { // 2^200 - 2^100
-		t2.Square(&t2)
-	}
-	t1.Multiply(&t2, &t1)     // 2^200 - 1
-	t1.Square(&t1)            // 2^201 - 2
-	for i := 1; i < 50; i++ { // 2^250 - 2^50
-		t1.Square(&t1)
-	}
-	t0.Multiply(&t1, &t0)     // 2^250 - 1
-	t0.Square(&t0)            // 2^251 - 2
-	t0.Square(&t0)            // 2^252 - 4
-	return v.Multiply(&t0, x) // 2^252 - 3 -> x^(2^252-3)
-}
-
-// sqrtM1 is 2^((p-1)/4), which squared is equal to -1 by Euler's Criterion.
-var sqrtM1 = &Element{1718705420411056, 234908883556509,
-	2233514472574048, 2117202627021982, 765476049583133}
-
-// SqrtRatio sets r to the non-negative square root of the ratio of u and v.
-//
-// If u/v is square, SqrtRatio returns r and 1. If u/v is not square, SqrtRatio
-// sets r according to Section 4.3 of draft-irtf-cfrg-ristretto255-decaf448-00,
-// and returns r and 0.
-func (r *Element) SqrtRatio(u, v *Element) (rr *Element, wasSquare int) {
-	var a, b Element
-
-	// r = (u * v3) * (u * v7)^((p-5)/8)
-	v2 := a.Square(v)
-	uv3 := b.Multiply(u, b.Multiply(v2, v))
-	uv7 := a.Multiply(uv3, a.Square(v2))
-	r.Multiply(uv3, r.Pow22523(uv7))
-
-	check := a.Multiply(v, a.Square(r)) // check = v * r^2
-
-	uNeg := b.Negate(u)
-	correctSignSqrt := check.Equal(u)
-	flippedSignSqrt := check.Equal(uNeg)
-	flippedSignSqrtI := check.Equal(uNeg.Multiply(uNeg, sqrtM1))
-
-	rPrime := b.Multiply(r, sqrtM1) // r_prime = SQRT_M1 * r
-	// r = CT_SELECT(r_prime IF flipped_sign_sqrt | flipped_sign_sqrt_i ELSE r)
-	r.Select(rPrime, r, flippedSignSqrt|flippedSignSqrtI)
-
-	r.Absolute(r) // Choose the nonnegative square root.
-	return r, correctSignSqrt | flippedSignSqrt
-}

curve25519/internal/field/fe_alias_test.go

@@ -1,126 +0,0 @@
-// Copyright (c) 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.
-
-package field
-
-import (
-	"testing"
-	"testing/quick"
-)
-
-func checkAliasingOneArg(f func(v, x *Element) *Element) func(v, x Element) bool {
-	return func(v, x Element) bool {
-		x1, v1 := x, x
-
-		// Calculate a reference f(x) without aliasing.
-		if out := f(&v, &x); out != &v && isInBounds(out) {
-			return false
-		}
-
-		// Test aliasing the argument and the receiver.
-		if out := f(&v1, &v1); out != &v1 || v1 != v {
-			return false
-		}
-
-		// Ensure the arguments was not modified.
-		return x == x1
-	}
-}
-
-func checkAliasingTwoArgs(f func(v, x, y *Element) *Element) func(v, x, y Element) bool {
-	return func(v, x, y Element) bool {
-		x1, y1, v1 := x, y, Element{}
-
-		// Calculate a reference f(x, y) without aliasing.
-		if out := f(&v, &x, &y); out != &v && isInBounds(out) {
-			return false
-		}
-
-		// Test aliasing the first argument and the receiver.
-		v1 = x
-		if out := f(&v1, &v1, &y); out != &v1 || v1 != v {
-			return false
-		}
-		// Test aliasing the second argument and the receiver.
-		v1 = y
-		if out := f(&v1, &x, &v1); out != &v1 || v1 != v {
-			return false
-		}
-
-		// Calculate a reference f(x, x) without aliasing.
-		if out := f(&v, &x, &x); out != &v {
-			return false
-		}
-
-		// Test aliasing the first argument and the receiver.
-		v1 = x
-		if out := f(&v1, &v1, &x); out != &v1 || v1 != v {
-			return false
-		}
-		// Test aliasing the second argument and the receiver.
-		v1 = x
-		if out := f(&v1, &x, &v1); out != &v1 || v1 != v {
-			return false
-		}
-		// Test aliasing both arguments and the receiver.
-		v1 = x
-		if out := f(&v1, &v1, &v1); out != &v1 || v1 != v {
-			return false
-		}
-
-		// Ensure the arguments were not modified.
-		return x == x1 && y == y1
-	}
-}
-
-// TestAliasing checks that receivers and arguments can alias each other without
-// leading to incorrect results. That is, it ensures that it's safe to write
-//
-//	v.Invert(v)
-//
-// or
-//
-//	v.Add(v, v)
-//
-// without any of the inputs getting clobbered by the output being written.
-func TestAliasing(t *testing.T) {
-	type target struct {
-		name     string
-		oneArgF  func(v, x *Element) *Element
-		twoArgsF func(v, x, y *Element) *Element
-	}
-	for _, tt := range []target{
-		{name: "Absolute", oneArgF: (*Element).Absolute},
-		{name: "Invert", oneArgF: (*Element).Invert},
-		{name: "Negate", oneArgF: (*Element).Negate},
-		{name: "Set", oneArgF: (*Element).Set},
-		{name: "Square", oneArgF: (*Element).Square},
-		{name: "Multiply", twoArgsF: (*Element).Multiply},
-		{name: "Add", twoArgsF: (*Element).Add},
-		{name: "Subtract", twoArgsF: (*Element).Subtract},
-		{
-			name: "Select0",
-			twoArgsF: func(v, x, y *Element) *Element {
-				return (*Element).Select(v, x, y, 0)
-			},
-		},
-		{
-			name: "Select1",
-			twoArgsF: func(v, x, y *Element) *Element {
-				return (*Element).Select(v, x, y, 1)
-			},
-		},
-	} {
-		var err error
-		switch {
-		case tt.oneArgF != nil:
-			err = quick.Check(checkAliasingOneArg(tt.oneArgF), &quick.Config{MaxCountScale: 1 << 8})
-		case tt.twoArgsF != nil:
-			err = quick.Check(checkAliasingTwoArgs(tt.twoArgsF), &quick.Config{MaxCountScale: 1 << 8})
-		}
-		if err != nil {
-			t.Errorf("%v: %v", tt.name, err)
-		}
-	}
-}

curve25519/internal/field/fe_amd64.go

@@ -1,16 +0,0 @@
-// Code generated by command: go run fe_amd64_asm.go -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field. DO NOT EDIT.
-
-//go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
-
-package field
-
-// feMul sets out = a * b. It works like feMulGeneric.
-//
-//go:noescape
-func feMul(out *Element, a *Element, b *Element)
-
-// feSquare sets out = a * a. It works like feSquareGeneric.
-//
-//go:noescape
-func feSquare(out *Element, a *Element)

curve25519/internal/field/fe_amd64.s

@@ -1,379 +0,0 @@
-// Code generated by command: go run fe_amd64_asm.go -out ../fe_amd64.s -stubs ../fe_amd64.go -pkg field. DO NOT EDIT.
-
-//go:build amd64 && gc && !purego
-// +build amd64,gc,!purego
-
-#include "textflag.h"
-
-// func feMul(out *Element, a *Element, b *Element)
-TEXT ·feMul(SB), NOSPLIT, $0-24
-	MOVQ a+8(FP), CX
-	MOVQ b+16(FP), BX
-
-	// r0 = a0×b0
-	MOVQ (CX), AX
-	MULQ (BX)
-	MOVQ AX, DI
-	MOVQ DX, SI
-
-	// r0 += 19×a1×b4
-	MOVQ   8(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   32(BX)
-	ADDQ   AX, DI
-	ADCQ   DX, SI
-
-	// r0 += 19×a2×b3
-	MOVQ   16(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   24(BX)
-	ADDQ   AX, DI
-	ADCQ   DX, SI
-
-	// r0 += 19×a3×b2
-	MOVQ   24(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   16(BX)
-	ADDQ   AX, DI
-	ADCQ   DX, SI
-
-	// r0 += 19×a4×b1
-	MOVQ   32(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   8(BX)
-	ADDQ   AX, DI
-	ADCQ   DX, SI
-
-	// r1 = a0×b1
-	MOVQ (CX), AX
-	MULQ 8(BX)
-	MOVQ AX, R9
-	MOVQ DX, R8
-
-	// r1 += a1×b0
-	MOVQ 8(CX), AX
-	MULQ (BX)
-	ADDQ AX, R9
-	ADCQ DX, R8
-
-	// r1 += 19×a2×b4
-	MOVQ   16(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   32(BX)
-	ADDQ   AX, R9
-	ADCQ   DX, R8
-
-	// r1 += 19×a3×b3
-	MOVQ   24(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   24(BX)
-	ADDQ   AX, R9
-	ADCQ   DX, R8
-
-	// r1 += 19×a4×b2
-	MOVQ   32(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   16(BX)
-	ADDQ   AX, R9
-	ADCQ   DX, R8
-
-	// r2 = a0×b2
-	MOVQ (CX), AX
-	MULQ 16(BX)
-	MOVQ AX, R11
-	MOVQ DX, R10
-
-	// r2 += a1×b1
-	MOVQ 8(CX), AX
-	MULQ 8(BX)
-	ADDQ AX, R11
-	ADCQ DX, R10
-
-	// r2 += a2×b0
-	MOVQ 16(CX), AX
-	MULQ (BX)
-	ADDQ AX, R11
-	ADCQ DX, R10
-
-	// r2 += 19×a3×b4
-	MOVQ   24(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   32(BX)
-	ADDQ   AX, R11
-	ADCQ   DX, R10
-
-	// r2 += 19×a4×b3
-	MOVQ   32(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   24(BX)
-	ADDQ   AX, R11
-	ADCQ   DX, R10
-
-	// r3 = a0×b3
-	MOVQ (CX), AX
-	MULQ 24(BX)
-	MOVQ AX, R13
-	MOVQ DX, R12
-
-	// r3 += a1×b2
-	MOVQ 8(CX), AX
-	MULQ 16(BX)
-	ADDQ AX, R13
-	ADCQ DX, R12
-
-	// r3 += a2×b1
-	MOVQ 16(CX), AX
-	MULQ 8(BX)
-	ADDQ AX, R13
-	ADCQ DX, R12
-
-	// r3 += a3×b0
-	MOVQ 24(CX), AX
-	MULQ (BX)
-	ADDQ AX, R13
-	ADCQ DX, R12
-
-	// r3 += 19×a4×b4
-	MOVQ   32(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   32(BX)
-	ADDQ   AX, R13
-	ADCQ   DX, R12
-
-	// r4 = a0×b4
-	MOVQ (CX), AX
-	MULQ 32(BX)
-	MOVQ AX, R15
-	MOVQ DX, R14
-
-	// r4 += a1×b3
-	MOVQ 8(CX), AX
-	MULQ 24(BX)
-	ADDQ AX, R15
-	ADCQ DX, R14
-
-	// r4 += a2×b2
-	MOVQ 16(CX), AX
-	MULQ 16(BX)
-	ADDQ AX, R15
-	ADCQ DX, R14
-
-	// r4 += a3×b1
-	MOVQ 24(CX), AX
-	MULQ 8(BX)
-	ADDQ AX, R15
-	ADCQ DX, R14
-
-	// r4 += a4×b0
-	MOVQ 32(CX), AX
-	MULQ (BX)
-	ADDQ AX, R15
-	ADCQ DX, R14
-
-	// First reduction chain
-	MOVQ   $0x0007ffffffffffff, AX
-	SHLQ   $0x0d, DI, SI
-	SHLQ   $0x0d, R9, R8
-	SHLQ   $0x0d, R11, R10
-	SHLQ   $0x0d, R13, R12
-	SHLQ   $0x0d, R15, R14
-	ANDQ   AX, DI
-	IMUL3Q $0x13, R14, R14
-	ADDQ   R14, DI
-	ANDQ   AX, R9
-	ADDQ   SI, R9
-	ANDQ   AX, R11
-	ADDQ   R8, R11
-	ANDQ   AX, R13
-	ADDQ   R10, R13
-	ANDQ   AX, R15
-	ADDQ   R12, R15
-
-	// Second reduction chain (carryPropagate)
-	MOVQ   DI, SI
-	SHRQ   $0x33, SI
-	MOVQ   R9, R8
-	SHRQ   $0x33, R8
-	MOVQ   R11, R10
-	SHRQ   $0x33, R10
-	MOVQ   R13, R12
-	SHRQ   $0x33, R12
-	MOVQ   R15, R14
-	SHRQ   $0x33, R14
-	ANDQ   AX, DI
-	IMUL3Q $0x13, R14, R14
-	ADDQ   R14, DI
-	ANDQ   AX, R9
-	ADDQ   SI, R9
-	ANDQ   AX, R11
-	ADDQ   R8, R11
-	ANDQ   AX, R13
-	ADDQ   R10, R13
-	ANDQ   AX, R15
-	ADDQ   R12, R15
-
-	// Store output
-	MOVQ out+0(FP), AX
-	MOVQ DI, (AX)
-	MOVQ R9, 8(AX)
-	MOVQ R11, 16(AX)
-	MOVQ R13, 24(AX)
-	MOVQ R15, 32(AX)
-	RET
-
-// func feSquare(out *Element, a *Element)
-TEXT ·feSquare(SB), NOSPLIT, $0-16
-	MOVQ a+8(FP), CX
-
-	// r0 = l0×l0
-	MOVQ (CX), AX
-	MULQ (CX)
-	MOVQ AX, SI
-	MOVQ DX, BX
-
-	// r0 += 38×l1×l4
-	MOVQ   8(CX), AX
-	IMUL3Q $0x26, AX, AX
-	MULQ   32(CX)
-	ADDQ   AX, SI
-	ADCQ   DX, BX
-
-	// r0 += 38×l2×l3
-	MOVQ   16(CX), AX
-	IMUL3Q $0x26, AX, AX
-	MULQ   24(CX)
-	ADDQ   AX, SI
-	ADCQ   DX, BX
-
-	// r1 = 2×l0×l1
-	MOVQ (CX), AX
-	SHLQ $0x01, AX
-	MULQ 8(CX)
-	MOVQ AX, R8
-	MOVQ DX, DI
-
-	// r1 += 38×l2×l4
-	MOVQ   16(CX), AX
-	IMUL3Q $0x26, AX, AX
-	MULQ   32(CX)
-	ADDQ   AX, R8
-	ADCQ   DX, DI
-
-	// r1 += 19×l3×l3
-	MOVQ   24(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   24(CX)
-	ADDQ   AX, R8
-	ADCQ   DX, DI
-
-	// r2 = 2×l0×l2
-	MOVQ (CX), AX
-	SHLQ $0x01, AX
-	MULQ 16(CX)
-	MOVQ AX, R10
-	MOVQ DX, R9
-
-	// r2 += l1×l1
-	MOVQ 8(CX), AX
-	MULQ 8(CX)
-	ADDQ AX, R10
-	ADCQ DX, R9
-
-	// r2 += 38×l3×l4
-	MOVQ   24(CX), AX
-	IMUL3Q $0x26, AX, AX
-	MULQ   32(CX)
-	ADDQ   AX, R10
-	ADCQ   DX, R9
-
-	// r3 = 2×l0×l3
-	MOVQ (CX), AX
-	SHLQ $0x01, AX
-	MULQ 24(CX)
-	MOVQ AX, R12
-	MOVQ DX, R11
-
-	// r3 += 2×l1×l2
-	MOVQ   8(CX), AX
-	IMUL3Q $0x02, AX, AX
-	MULQ   16(CX)
-	ADDQ   AX, R12
-	ADCQ   DX, R11
-
-	// r3 += 19×l4×l4
-	MOVQ   32(CX), AX
-	IMUL3Q $0x13, AX, AX
-	MULQ   32(CX)
-	ADDQ   AX, R12
-	ADCQ   DX, R11
-
-	// r4 = 2×l0×l4
-	MOVQ (CX), AX
-	SHLQ $0x01, AX
-	MULQ 32(CX)
-	MOVQ AX, R14
-	MOVQ DX, R13
-
-	// r4 += 2×l1×l3
-	MOVQ   8(CX), AX
-	IMUL3Q $0x02, AX, AX
-	MULQ   24(CX)
-	ADDQ   AX, R14
-	ADCQ   DX, R13
-
-	// r4 += l2×l2
-	MOVQ 16(CX), AX
-	MULQ 16(CX)
-	ADDQ AX, R14
-	ADCQ DX, R13
-
-	// First reduction chain
-	MOVQ   $0x0007ffffffffffff, AX
-	SHLQ   $0x0d, SI, BX
-	SHLQ   $0x0d, R8, DI
-	SHLQ   $0x0d, R10, R9
-	SHLQ   $0x0d, R12, R11
-	SHLQ   $0x0d, R14, R13
-	ANDQ   AX, SI
-	IMUL3Q $0x13, R13, R13
-	ADDQ   R13, SI
-	ANDQ   AX, R8
-	ADDQ   BX, R8
-	ANDQ   AX, R10
-	ADDQ   DI, R10
-	ANDQ   AX, R12
-	ADDQ   R9, R12
-	ANDQ   AX, R14
-	ADDQ   R11, R14
-
-	// Second reduction chain (carryPropagate)
-	MOVQ   SI, BX
-	SHRQ   $0x33, BX
-	MOVQ   R8, DI
-	SHRQ   $0x33, DI
-	MOVQ   R10, R9
-	SHRQ   $0x33, R9
-	MOVQ   R12, R11
-	SHRQ   $0x33, R11
-	MOVQ   R14, R13
-	SHRQ   $0x33, R13
-	ANDQ   AX, SI
-	IMUL3Q $0x13, R13, R13
-	ADDQ   R13, SI
-	ANDQ   AX, R8
-	ADDQ   BX, R8
-	ANDQ   AX, R10
-	ADDQ   DI, R10
-	ANDQ   AX, R12
-	ADDQ   R9, R12
-	ANDQ   AX, R14
-	ADDQ   R11, R14
-
-	// Store output
-	MOVQ out+0(FP), AX
-	MOVQ SI, (AX)
-	MOVQ R8, 8(AX)
-	MOVQ R10, 16(AX)
-	MOVQ R12, 24(AX)
-	MOVQ R14, 32(AX)
-	RET

curve25519/internal/field/fe_amd64_noasm.go

@@ -1,12 +0,0 @@
-// Copyright (c) 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.
-
-//go:build !amd64 || !gc || purego
-// +build !amd64 !gc purego
-
-package field
-
-func feMul(v, x, y *Element) { feMulGeneric(v, x, y) }
-
-func feSquare(v, x *Element) { feSquareGeneric(v, x) }

curve25519/internal/field/fe_arm64.go

@@ -1,16 +0,0 @@
-// Copyright (c) 2020 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.
-
-//go:build arm64 && gc && !purego
-// +build arm64,gc,!purego
-
-package field
-
-//go:noescape
-func carryPropagate(v *Element)
-
-func (v *Element) carryPropagate() *Element {
-	carryPropagate(v)
-	return v
-}

curve25519/internal/field/fe_arm64.s

@@ -1,43 +0,0 @@
-// Copyright (c) 2020 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.
-
-//go:build arm64 && gc && !purego
-// +build arm64,gc,!purego
-
-#include "textflag.h"
-
-// carryPropagate works exactly like carryPropagateGeneric and uses the
-// same AND, ADD, and LSR+MADD instructions emitted by the compiler, but
-// avoids loading R0-R4 twice and uses LDP and STP.
-//
-// See https://golang.org/issues/43145 for the main compiler issue.
-//
-// func carryPropagate(v *Element)
-TEXT ·carryPropagate(SB),NOFRAME|NOSPLIT,$0-8
-	MOVD v+0(FP), R20
-
-	LDP 0(R20), (R0, R1)
-	LDP 16(R20), (R2, R3)
-	MOVD 32(R20), R4
-
-	AND $0x7ffffffffffff, R0, R10
-	AND $0x7ffffffffffff, R1, R11
-	AND $0x7ffffffffffff, R2, R12
-	AND $0x7ffffffffffff, R3, R13
-	AND $0x7ffffffffffff, R4, R14
-
-	ADD R0>>51, R11, R11
-	ADD R1>>51, R12, R12
-	ADD R2>>51, R13, R13
-	ADD R3>>51, R14, R14
-	// R4>>51 * 19 + R10 -> R10
-	LSR $51, R4, R21
-	MOVD $19, R22
-	MADD R22, R10, R21, R10
-
-	STP (R10, R11), 0(R20)
-	STP (R12, R13), 16(R20)
-	MOVD R14, 32(R20)
-
-	RET

curve25519/internal/field/fe_arm64_noasm.go

@@ -1,12 +0,0 @@
-// Copyright (c) 2021 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.
-
-//go:build !arm64 || !gc || purego
-// +build !arm64 !gc purego
-
-package field
-
-func (v *Element) carryPropagate() *Element {
-	return v.carryPropagateGeneric()
-}

curve25519/internal/field/fe_bench_test.go

@@ -1,36 +0,0 @@
-// Copyright (c) 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.
-
-package field
-
-import "testing"
-
-func BenchmarkAdd(b *testing.B) {
-	var x, y Element
-	x.One()
-	y.Add(feOne, feOne)
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		x.Add(&x, &y)
-	}
-}
-
-func BenchmarkMultiply(b *testing.B) {
-	var x, y Element
-	x.One()
-	y.Add(feOne, feOne)
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		x.Multiply(&x, &y)
-	}
-}
-
-func BenchmarkMult32(b *testing.B) {
-	var x Element
-	x.One()
-	b.ResetTimer()
-	for i := 0; i < b.N; i++ {
-		x.Mult32(&x, 0xaa42aa42)
-	}
-}

curve25519/internal/field/fe_generic.go

@@ -1,264 +0,0 @@
-// Copyright (c) 2017 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 field
-
-import "math/bits"
-
-// uint128 holds a 128-bit number as two 64-bit limbs, for use with the
-// bits.Mul64 and bits.Add64 intrinsics.
-type uint128 struct {
-	lo, hi uint64
-}
-
-// mul64 returns a * b.
-func mul64(a, b uint64) uint128 {
-	hi, lo := bits.Mul64(a, b)
-	return uint128{lo, hi}
-}
-
-// addMul64 returns v + a * b.
-func addMul64(v uint128, a, b uint64) uint128 {
-	hi, lo := bits.Mul64(a, b)
-	lo, c := bits.Add64(lo, v.lo, 0)
-	hi, _ = bits.Add64(hi, v.hi, c)
-	return uint128{lo, hi}
-}
-
-// shiftRightBy51 returns a >> 51. a is assumed to be at most 115 bits.
-func shiftRightBy51(a uint128) uint64 {
-	return (a.hi << (64 - 51)) | (a.lo >> 51)
-}
-
-func feMulGeneric(v, a, b *Element) {
-	a0 := a.l0
-	a1 := a.l1
-	a2 := a.l2
-	a3 := a.l3
-	a4 := a.l4
-
-	b0 := b.l0
-	b1 := b.l1
-	b2 := b.l2
-	b3 := b.l3
-	b4 := b.l4
-
-	// Limb multiplication works like pen-and-paper columnar multiplication, but
-	// with 51-bit limbs instead of digits.
-	//
-	//                          a4   a3   a2   a1   a0  x
-	//                          b4   b3   b2   b1   b0  =
-	//                         ------------------------
-	//                        a4b0 a3b0 a2b0 a1b0 a0b0  +
-	//                   a4b1 a3b1 a2b1 a1b1 a0b1       +
-	//              a4b2 a3b2 a2b2 a1b2 a0b2            +
-	//         a4b3 a3b3 a2b3 a1b3 a0b3                 +
-	//    a4b4 a3b4 a2b4 a1b4 a0b4                      =
-	//   ----------------------------------------------
-	//      r8   r7   r6   r5   r4   r3   r2   r1   r0
-	//
-	// We can then use the reduction identity (a * 2²⁵⁵ + b = a * 19 + b) to
-	// reduce the limbs that would overflow 255 bits. r5 * 2²⁵⁵ becomes 19 * r5,
-	// r6 * 2³⁰⁶ becomes 19 * r6 * 2⁵¹, etc.
-	//
-	// Reduction can be carried out simultaneously to multiplication. For
-	// example, we do not compute r5: whenever the result of a multiplication
-	// belongs to r5, like a1b4, we multiply it by 19 and add the result to r0.
-	//
-	//            a4b0    a3b0    a2b0    a1b0    a0b0  +
-	//            a3b1    a2b1    a1b1    a0b1 19×a4b1  +
-	//            a2b2    a1b2    a0b2 19×a4b2 19×a3b2  +
-	//            a1b3    a0b3 19×a4b3 19×a3b3 19×a2b3  +
-	//            a0b4 19×a4b4 19×a3b4 19×a2b4 19×a1b4  =
-	//           --------------------------------------
-	//              r4      r3      r2      r1      r0
-	//
-	// Finally we add up the columns into wide, overlapping limbs.
-
-	a1_19 := a1 * 19
-	a2_19 := a2 * 19
-	a3_19 := a3 * 19
-	a4_19 := a4 * 19
-
-	// r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
-	r0 := mul64(a0, b0)
-	r0 = addMul64(r0, a1_19, b4)
-	r0 = addMul64(r0, a2_19, b3)
-	r0 = addMul64(r0, a3_19, b2)
-	r0 = addMul64(r0, a4_19, b1)
-
-	// r1 = a0×b1 + a1×b0 + 19×(a2×b4 + a3×b3 + a4×b2)
-	r1 := mul64(a0, b1)
-	r1 = addMul64(r1, a1, b0)
-	r1 = addMul64(r1, a2_19, b4)
-	r1 = addMul64(r1, a3_19, b3)
-	r1 = addMul64(r1, a4_19, b2)
-
-	// r2 = a0×b2 + a1×b1 + a2×b0 + 19×(a3×b4 + a4×b3)
-	r2 := mul64(a0, b2)
-	r2 = addMul64(r2, a1, b1)
-	r2 = addMul64(r2, a2, b0)
-	r2 = addMul64(r2, a3_19, b4)
-	r2 = addMul64(r2, a4_19, b3)
-
-	// r3 = a0×b3 + a1×b2 + a2×b1 + a3×b0 + 19×a4×b4
-	r3 := mul64(a0, b3)
-	r3 = addMul64(r3, a1, b2)
-	r3 = addMul64(r3, a2, b1)
-	r3 = addMul64(r3, a3, b0)
-	r3 = addMul64(r3, a4_19, b4)
-
-	// r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
-	r4 := mul64(a0, b4)
-	r4 = addMul64(r4, a1, b3)
-	r4 = addMul64(r4, a2, b2)
-	r4 = addMul64(r4, a3, b1)
-	r4 = addMul64(r4, a4, b0)
-
-	// After the multiplication, we need to reduce (carry) the five coefficients
-	// to obtain a result with limbs that are at most slightly larger than 2⁵¹,
-	// to respect the Element invariant.
-	//
-	// Overall, the reduction works the same as carryPropagate, except with
-	// wider inputs: we take the carry for each coefficient by shifting it right
-	// by 51, and add it to the limb above it. The top carry is multiplied by 19
-	// according to the reduction identity and added to the lowest limb.
-	//
-	// The largest coefficient (r0) will be at most 111 bits, which guarantees
-	// that all carries are at most 111 - 51 = 60 bits, which fits in a uint64.
-	//
-	//     r0 = a0×b0 + 19×(a1×b4 + a2×b3 + a3×b2 + a4×b1)
-	//     r0 < 2⁵²×2⁵² + 19×(2⁵²×2⁵² + 2⁵²×2⁵² + 2⁵²×2⁵² + 2⁵²×2⁵²)
-	//     r0 < (1 + 19 × 4) × 2⁵² × 2⁵²
-	//     r0 < 2⁷ × 2⁵² × 2⁵²
-	//     r0 < 2¹¹¹
-	//
-	// Moreover, the top coefficient (r4) is at most 107 bits, so c4 is at most
-	// 56 bits, and c4 * 19 is at most 61 bits, which again fits in a uint64 and
-	// allows us to easily apply the reduction identity.
-	//
-	//     r4 = a0×b4 + a1×b3 + a2×b2 + a3×b1 + a4×b0
-	//     r4 < 5 × 2⁵² × 2⁵²
-	//     r4 < 2¹⁰⁷
-	//
-
-	c0 := shiftRightBy51(r0)
-	c1 := shiftRightBy51(r1)
-	c2 := shiftRightBy51(r2)
-	c3 := shiftRightBy51(r3)
-	c4 := shiftRightBy51(r4)
-
-	rr0 := r0.lo&maskLow51Bits + c4*19
-	rr1 := r1.lo&maskLow51Bits + c0
-	rr2 := r2.lo&maskLow51Bits + c1
-	rr3 := r3.lo&maskLow51Bits + c2
-	rr4 := r4.lo&maskLow51Bits + c3
-
-	// Now all coefficients fit into 64-bit registers but are still too large to
-	// be passed around as a Element. We therefore do one last carry chain,
-	// where the carries will be small enough to fit in the wiggle room above 2⁵¹.
-	*v = Element{rr0, rr1, rr2, rr3, rr4}
-	v.carryPropagate()
-}
-
-func feSquareGeneric(v, a *Element) {
-	l0 := a.l0
-	l1 := a.l1
-	l2 := a.l2
-	l3 := a.l3
-	l4 := a.l4
-
-	// Squaring works precisely like multiplication above, but thanks to its
-	// symmetry we get to group a few terms together.
-	//
-	//                          l4   l3   l2   l1   l0  x
-	//                          l4   l3   l2   l1   l0  =
-	//                         ------------------------
-	//                        l4l0 l3l0 l2l0 l1l0 l0l0  +
-	//                   l4l1 l3l1 l2l1 l1l1 l0l1       +
-	//              l4l2 l3l2 l2l2 l1l2 l0l2            +
-	//         l4l3 l3l3 l2l3 l1l3 l0l3                 +
-	//    l4l4 l3l4 l2l4 l1l4 l0l4                      =
-	//   ----------------------------------------------
-	//      r8   r7   r6   r5   r4   r3   r2   r1   r0
-	//
-	//            l4l0    l3l0    l2l0    l1l0    l0l0  +
-	//            l3l1    l2l1    l1l1    l0l1 19×l4l1  +
-	//            l2l2    l1l2    l0l2 19×l4l2 19×l3l2  +
-	//            l1l3    l0l3 19×l4l3 19×l3l3 19×l2l3  +
-	//            l0l4 19×l4l4 19×l3l4 19×l2l4 19×l1l4  =
-	//           --------------------------------------
-	//              r4      r3      r2      r1      r0
-	//
-	// With precomputed 2×, 19×, and 2×19× terms, we can compute each limb with
-	// only three Mul64 and four Add64, instead of five and eight.
-
-	l0_2 := l0 * 2
-	l1_2 := l1 * 2
-
-	l1_38 := l1 * 38
-	l2_38 := l2 * 38
-	l3_38 := l3 * 38
-
-	l3_19 := l3 * 19
-	l4_19 := l4 * 19
-
-	// r0 = l0×l0 + 19×(l1×l4 + l2×l3 + l3×l2 + l4×l1) = l0×l0 + 19×2×(l1×l4 + l2×l3)
-	r0 := mul64(l0, l0)
-	r0 = addMul64(r0, l1_38, l4)
-	r0 = addMul64(r0, l2_38, l3)
-
-	// r1 = l0×l1 + l1×l0 + 19×(l2×l4 + l3×l3 + l4×l2) = 2×l0×l1 + 19×2×l2×l4 + 19×l3×l3
-	r1 := mul64(l0_2, l1)
-	r1 = addMul64(r1, l2_38, l4)
-	r1 = addMul64(r1, l3_19, l3)
-
-	// r2 = l0×l2 + l1×l1 + l2×l0 + 19×(l3×l4 + l4×l3) = 2×l0×l2 + l1×l1 + 19×2×l3×l4
-	r2 := mul64(l0_2, l2)
-	r2 = addMul64(r2, l1, l1)
-	r2 = addMul64(r2, l3_38, l4)
-
-	// r3 = l0×l3 + l1×l2 + l2×l1 + l3×l0 + 19×l4×l4 = 2×l0×l3 + 2×l1×l2 + 19×l4×l4
-	r3 := mul64(l0_2, l3)
-	r3 = addMul64(r3, l1_2, l2)
-	r3 = addMul64(r3, l4_19, l4)
-
-	// r4 = l0×l4 + l1×l3 + l2×l2 + l3×l1 + l4×l0 = 2×l0×l4 + 2×l1×l3 + l2×l2
-	r4 := mul64(l0_2, l4)
-	r4 = addMul64(r4, l1_2, l3)
-	r4 = addMul64(r4, l2, l2)
-
-	c0 := shiftRightBy51(r0)
-	c1 := shiftRightBy51(r1)
-	c2 := shiftRightBy51(r2)
-	c3 := shiftRightBy51(r3)
-	c4 := shiftRightBy51(r4)
-
-	rr0 := r0.lo&maskLow51Bits + c4*19
-	rr1 := r1.lo&maskLow51Bits + c0
-	rr2 := r2.lo&maskLow51Bits + c1
-	rr3 := r3.lo&maskLow51Bits + c2
-	rr4 := r4.lo&maskLow51Bits + c3
-
-	*v = Element{rr0, rr1, rr2, rr3, rr4}
-	v.carryPropagate()
-}
-
-// carryPropagate brings the limbs below 52 bits by applying the reduction
-// identity (a * 2²⁵⁵ + b = a * 19 + b) to the l4 carry. TODO inline
-func (v *Element) carryPropagateGeneric() *Element {
-	c0 := v.l0 >> 51
-	c1 := v.l1 >> 51
-	c2 := v.l2 >> 51
-	c3 := v.l3 >> 51
-	c4 := v.l4 >> 51
-
-	v.l0 = v.l0&maskLow51Bits + c4*19
-	v.l1 = v.l1&maskLow51Bits + c0
-	v.l2 = v.l2&maskLow51Bits + c1
-	v.l3 = v.l3&maskLow51Bits + c2
-	v.l4 = v.l4&maskLow51Bits + c3
-
-	return v
-}

curve25519/internal/field/fe_test.go

@@ -1,558 +0,0 @@
-// Copyright (c) 2017 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 field
-
-import (
-	"bytes"
-	"crypto/rand"
-	"encoding/hex"
-	"io"
-	"math/big"
-	"math/bits"
-	mathrand "math/rand"
-	"reflect"
-	"testing"
-	"testing/quick"
-)
-
-func (v Element) String() string {
-	return hex.EncodeToString(v.Bytes())
-}
-
-// quickCheckConfig1024 will make each quickcheck test run (1024 * -quickchecks)
-// times. The default value of -quickchecks is 100.
-var quickCheckConfig1024 = &quick.Config{MaxCountScale: 1 << 10}
-
-func generateFieldElement(rand *mathrand.Rand) Element {
-	const maskLow52Bits = (1 << 52) - 1
-	return Element{
-		rand.Uint64() & maskLow52Bits,
-		rand.Uint64() & maskLow52Bits,
-		rand.Uint64() & maskLow52Bits,
-		rand.Uint64() & maskLow52Bits,
-		rand.Uint64() & maskLow52Bits,
-	}
-}
-
-// weirdLimbs can be combined to generate a range of edge-case field elements.
-// 0 and -1 are intentionally more weighted, as they combine well.
-var (
-	weirdLimbs51 = []uint64{
-		0, 0, 0, 0,
-		1,
-		19 - 1,
-		19,
-		0x2aaaaaaaaaaaa,
-		0x5555555555555,
-		(1 << 51) - 20,
-		(1 << 51) - 19,
-		(1 << 51) - 1, (1 << 51) - 1,
-		(1 << 51) - 1, (1 << 51) - 1,
-	}
-	weirdLimbs52 = []uint64{
-		0, 0, 0, 0, 0, 0,
-		1,
-		19 - 1,
-		19,
-		0x2aaaaaaaaaaaa,
-		0x5555555555555,
-		(1 << 51) - 20,
-		(1 << 51) - 19,
-		(1 << 51) - 1, (1 << 51) - 1,
-		(1 << 51) - 1, (1 << 51) - 1,
-		(1 << 51) - 1, (1 << 51) - 1,
-		1 << 51,
-		(1 << 51) + 1,
-		(1 << 52) - 19,
-		(1 << 52) - 1,
-	}
-)
-
-func generateWeirdFieldElement(rand *mathrand.Rand) Element {
-	return Element{
-		weirdLimbs52[rand.Intn(len(weirdLimbs52))],
-		weirdLimbs51[rand.Intn(len(weirdLimbs51))],
-		weirdLimbs51[rand.Intn(len(weirdLimbs51))],
-		weirdLimbs51[rand.Intn(len(weirdLimbs51))],
-		weirdLimbs51[rand.Intn(len(weirdLimbs51))],
-	}
-}
-
-func (Element) Generate(rand *mathrand.Rand, size int) reflect.Value {
-	if rand.Intn(2) == 0 {
-		return reflect.ValueOf(generateWeirdFieldElement(rand))
-	}
-	return reflect.ValueOf(generateFieldElement(rand))
-}
-
-// isInBounds returns whether the element is within the expected bit size bounds
-// after a light reduction.
-func isInBounds(x *Element) bool {
-	return bits.Len64(x.l0) <= 52 &&
-		bits.Len64(x.l1) <= 52 &&
-		bits.Len64(x.l2) <= 52 &&
-		bits.Len64(x.l3) <= 52 &&
-		bits.Len64(x.l4) <= 52
-}
-
-func TestMultiplyDistributesOverAdd(t *testing.T) {
-	multiplyDistributesOverAdd := func(x, y, z Element) bool {
-		// Compute t1 = (x+y)*z
-		t1 := new(Element)
-		t1.Add(&x, &y)
-		t1.Multiply(t1, &z)
-
-		// Compute t2 = x*z + y*z
-		t2 := new(Element)
-		t3 := new(Element)
-		t2.Multiply(&x, &z)
-		t3.Multiply(&y, &z)
-		t2.Add(t2, t3)
-
-		return t1.Equal(t2) == 1 && isInBounds(t1) && isInBounds(t2)
-	}
-
-	if err := quick.Check(multiplyDistributesOverAdd, quickCheckConfig1024); err != nil {
-		t.Error(err)
-	}
-}
-
-func TestMul64to128(t *testing.T) {
-	a := uint64(5)
-	b := uint64(5)
-	r := mul64(a, b)
-	if r.lo != 0x19 || r.hi != 0 {
-		t.Errorf("lo-range wide mult failed, got %d + %d*(2**64)", r.lo, r.hi)
-	}
-
-	a = uint64(18014398509481983) // 2^54 - 1
-	b = uint64(18014398509481983) // 2^54 - 1
-	r = mul64(a, b)
-	if r.lo != 0xff80000000000001 || r.hi != 0xfffffffffff {
-		t.Errorf("hi-range wide mult failed, got %d + %d*(2**64)", r.lo, r.hi)
-	}
-
-	a = uint64(1125899906842661)
-	b = uint64(2097155)
-	r = mul64(a, b)
-	r = addMul64(r, a, b)
-	r = addMul64(r, a, b)
-	r = addMul64(r, a, b)
-	r = addMul64(r, a, b)
-	if r.lo != 16888498990613035 || r.hi != 640 {
-		t.Errorf("wrong answer: %d + %d*(2**64)", r.lo, r.hi)
-	}
-}
-
-func TestSetBytesRoundTrip(t *testing.T) {
-	f1 := func(in [32]byte, fe Element) bool {
-		fe.SetBytes(in[:])
-
-		// Mask the most significant bit as it's ignored by SetBytes. (Now
-		// instead of earlier so we check the masking in SetBytes is working.)
-		in[len(in)-1] &= (1 << 7) - 1
-
-		return bytes.Equal(in[:], fe.Bytes()) && isInBounds(&fe)
-	}
-	if err := quick.Check(f1, nil); err != nil {
-		t.Errorf("failed bytes->FE->bytes round-trip: %v", err)
-	}
-
-	f2 := func(fe, r Element) bool {
-		r.SetBytes(fe.Bytes())
-
-		// Intentionally not using Equal not to go through Bytes again.
-		// Calling reduce because both Generate and SetBytes can produce
-		// non-canonical representations.
-		fe.reduce()
-		r.reduce()
-		return fe == r
-	}
-	if err := quick.Check(f2, nil); err != nil {
-		t.Errorf("failed FE->bytes->FE round-trip: %v", err)
-	}
-
-	// Check some fixed vectors from dalek
-	type feRTTest struct {
-		fe Element
-		b  []byte
-	}
-	var tests = []feRTTest{
-		{
-			fe: Element{358744748052810, 1691584618240980, 977650209285361, 1429865912637724, 560044844278676},
-			b:  []byte{74, 209, 69, 197, 70, 70, 161, 222, 56, 226, 229, 19, 112, 60, 25, 92, 187, 74, 222, 56, 50, 153, 51, 233, 40, 74, 57, 6, 160, 185, 213, 31},
-		},
-		{
-			fe: Element{84926274344903, 473620666599931, 365590438845504, 1028470286882429, 2146499180330972},
-			b:  []byte{199, 23, 106, 112, 61, 77, 216, 79, 186, 60, 11, 118, 13, 16, 103, 15, 42, 32, 83, 250, 44, 57, 204, 198, 78, 199, 253, 119, 146, 172, 3, 122},
-		},
-	}
-
-	for _, tt := range tests {
-		b := tt.fe.Bytes()
-		if !bytes.Equal(b, tt.b) || new(Element).SetBytes(tt.b).Equal(&tt.fe) != 1 {
-			t.Errorf("Failed fixed roundtrip: %v", tt)
-		}
-	}
-}
-
-func swapEndianness(buf []byte) []byte {
-	for i := 0; i < len(buf)/2; i++ {
-		buf[i], buf[len(buf)-i-1] = buf[len(buf)-i-1], buf[i]
-	}
-	return buf
-}
-
-func TestBytesBigEquivalence(t *testing.T) {
-	f1 := func(in [32]byte, fe, fe1 Element) bool {
-		fe.SetBytes(in[:])
-
-		in[len(in)-1] &= (1 << 7) - 1 // mask the most significant bit
-		b := new(big.Int).SetBytes(swapEndianness(in[:]))
-		fe1.fromBig(b)
-
-		if fe != fe1 {
-			return false
-		}
-
-		buf := make([]byte, 32) // pad with zeroes
-		copy(buf, swapEndianness(fe1.toBig().Bytes()))
-
-		return bytes.Equal(fe.Bytes(), buf) && isInBounds(&fe) && isInBounds(&fe1)
-	}
-	if err := quick.Check(f1, nil); err != nil {
-		t.Error(err)
-	}
-}
-
-// fromBig sets v = n, and returns v. The bit length of n must not exceed 256.
-func (v *Element) fromBig(n *big.Int) *Element {
-	if n.BitLen() > 32*8 {
-		panic("edwards25519: invalid field element input size")
-	}
-
-	buf := make([]byte, 0, 32)
-	for _, word := range n.Bits() {
-		for i := 0; i < bits.UintSize; i += 8 {
-			if len(buf) >= cap(buf) {
-				break
-			}
-			buf = append(buf, byte(word))
-			word >>= 8
-		}
-	}
-
-	return v.SetBytes(buf[:32])
-}
-
-func (v *Element) fromDecimal(s string) *Element {
-	n, ok := new(big.Int).SetString(s, 10)
-	if !ok {
-		panic("not a valid decimal: " + s)
-	}
-	return v.fromBig(n)
-}
-
-// toBig returns v as a big.Int.
-func (v *Element) toBig() *big.Int {
-	buf := v.Bytes()
-
-	words := make([]big.Word, 32*8/bits.UintSize)
-	for n := range words {
-		for i := 0; i < bits.UintSize; i += 8 {
-			if len(buf) == 0 {
-				break
-			}
-			words[n] |= big.Word(buf[0]) << big.Word(i)
-			buf = buf[1:]
-		}
-	}
-
-	return new(big.Int).SetBits(words)
-}
-
-func TestDecimalConstants(t *testing.T) {
-	sqrtM1String := "19681161376707505956807079304988542015446066515923890162744021073123829784752"
-	if exp := new(Element).fromDecimal(sqrtM1String); sqrtM1.Equal(exp) != 1 {
-		t.Errorf("sqrtM1 is %v, expected %v", sqrtM1, exp)
-	}
-	// d is in the parent package, and we don't want to expose d or fromDecimal.
-	// dString := "37095705934669439343138083508754565189542113879843219016388785533085940283555"
-	// if exp := new(Element).fromDecimal(dString); d.Equal(exp) != 1 {
-	// 	t.Errorf("d is %v, expected %v", d, exp)
-	// }
-}
-
-func TestSetBytesRoundTripEdgeCases(t *testing.T) {
-	// TODO: values close to 0, close to 2^255-19, between 2^255-19 and 2^255-1,
-	// and between 2^255 and 2^256-1. Test both the documented SetBytes
-	// behavior, and that Bytes reduces them.
-}
-
-// Tests self-consistency between Multiply and Square.
-func TestConsistency(t *testing.T) {
-	var x Element
-	var x2, x2sq Element
-
-	x = Element{1, 1, 1, 1, 1}
-	x2.Multiply(&x, &x)
-	x2sq.Square(&x)
-
-	if x2 != x2sq {
-		t.Fatalf("all ones failed\nmul: %x\nsqr: %x\n", x2, x2sq)
-	}
-
-	var bytes [32]byte
-
-	_, err := io.ReadFull(rand.Reader, bytes[:])
-	if err != nil {
-		t.Fatal(err)
-	}
-	x.SetBytes(bytes[:])
-
-	x2.Multiply(&x, &x)
-	x2sq.Square(&x)
-
-	if x2 != x2sq {
-		t.Fatalf("all ones failed\nmul: %x\nsqr: %x\n", x2, x2sq)
-	}
-}
-
-func TestEqual(t *testing.T) {
-	x := Element{1, 1, 1, 1, 1}
-	y := Element{5, 4, 3, 2, 1}
-
-	eq := x.Equal(&x)
-	if eq != 1 {
-		t.Errorf("wrong about equality")
-	}
-
-	eq = x.Equal(&y)
-	if eq != 0 {
-		t.Errorf("wrong about inequality")
-	}
-}
-
-func TestInvert(t *testing.T) {
-	x := Element{1, 1, 1, 1, 1}
-	one := Element{1, 0, 0, 0, 0}
-	var xinv, r Element
-
-	xinv.Invert(&x)
-	r.Multiply(&x, &xinv)
-	r.reduce()
-
-	if one != r {
-		t.Errorf("inversion identity failed, got: %x", r)
-	}
-
-	var bytes [32]byte
-
-	_, err := io.ReadFull(rand.Reader, bytes[:])
-	if err != nil {
-		t.Fatal(err)
-	}
-	x.SetBytes(bytes[:])
-
-	xinv.Invert(&x)
-	r.Multiply(&x, &xinv)
-	r.reduce()
-
-	if one != r {
-		t.Errorf("random inversion identity failed, got: %x for field element %x", r, x)
-	}
-
-	zero := Element{}
-	x.Set(&zero)
-	if xx := xinv.Invert(&x); xx != &xinv {
-		t.Errorf("inverting zero did not return the receiver")
-	} else if xinv.Equal(&zero) != 1 {
-		t.Errorf("inverting zero did not return zero")
-	}
-}
-
-func TestSelectSwap(t *testing.T) {
-	a := Element{358744748052810, 1691584618240980, 977650209285361, 1429865912637724, 560044844278676}
-	b := Element{84926274344903, 473620666599931, 365590438845504, 1028470286882429, 2146499180330972}
-
-	var c, d Element
-
-	c.Select(&a, &b, 1)
-	d.Select(&a, &b, 0)
-
-	if c.Equal(&a) != 1 || d.Equal(&b) != 1 {
-		t.Errorf("Select failed")
-	}
-
-	c.Swap(&d, 0)
-
-	if c.Equal(&a) != 1 || d.Equal(&b) != 1 {
-		t.Errorf("Swap failed")
-	}
-
-	c.Swap(&d, 1)
-
-	if c.Equal(&b) != 1 || d.Equal(&a) != 1 {
-		t.Errorf("Swap failed")
-	}
-}
-
-func TestMult32(t *testing.T) {
-	mult32EquivalentToMul := func(x Element, y uint32) bool {
-		t1 := new(Element)
-		for i := 0; i < 100; i++ {
-			t1.Mult32(&x, y)
-		}
-
-		ty := new(Element)
-		ty.l0 = uint64(y)
-
-		t2 := new(Element)
-		for i := 0; i < 100; i++ {
-			t2.Multiply(&x, ty)
-		}
-
-		return t1.Equal(t2) == 1 && isInBounds(t1) && isInBounds(t2)
-	}
-
-	if err := quick.Check(mult32EquivalentToMul, quickCheckConfig1024); err != nil {
-		t.Error(err)
-	}
-}
-
-func TestSqrtRatio(t *testing.T) {
-	// From draft-irtf-cfrg-ristretto255-decaf448-00, Appendix A.4.
-	type test struct {
-		u, v      string
-		wasSquare int
-		r         string
-	}
-	var tests = []test{
-		// If u is 0, the function is defined to return (0, TRUE), even if v
-		// is zero. Note that where used in this package, the denominator v
-		// is never zero.
-		{
-			"0000000000000000000000000000000000000000000000000000000000000000",
-			"0000000000000000000000000000000000000000000000000000000000000000",
-			1, "0000000000000000000000000000000000000000000000000000000000000000",
-		},
-		// 0/1 == 0²
-		{
-			"0000000000000000000000000000000000000000000000000000000000000000",
-			"0100000000000000000000000000000000000000000000000000000000000000",
-			1, "0000000000000000000000000000000000000000000000000000000000000000",
-		},
-		// If u is non-zero and v is zero, defined to return (0, FALSE).
-		{
-			"0100000000000000000000000000000000000000000000000000000000000000",
-			"0000000000000000000000000000000000000000000000000000000000000000",
-			0, "0000000000000000000000000000000000000000000000000000000000000000",
-		},
-		// 2/1 is not square in this field.
-		{
-			"0200000000000000000000000000000000000000000000000000000000000000",
-			"0100000000000000000000000000000000000000000000000000000000000000",
-			0, "3c5ff1b5d8e4113b871bd052f9e7bcd0582804c266ffb2d4f4203eb07fdb7c54",
-		},
-		// 4/1 == 2²
-		{
-			"0400000000000000000000000000000000000000000000000000000000000000",
-			"0100000000000000000000000000000000000000000000000000000000000000",
-			1, "0200000000000000000000000000000000000000000000000000000000000000",
-		},
-		// 1/4 == (2⁻¹)² == (2^(p-2))² per Euler's theorem
-		{
-			"0100000000000000000000000000000000000000000000000000000000000000",
-			"0400000000000000000000000000000000000000000000000000000000000000",
-			1, "f6ffffffffffffffffffffffffffffffffffffffffffffffffffffffffffff3f",
-		},
-	}
-
-	for i, tt := range tests {
-		u := new(Element).SetBytes(decodeHex(tt.u))
-		v := new(Element).SetBytes(decodeHex(tt.v))
-		want := new(Element).SetBytes(decodeHex(tt.r))
-		got, wasSquare := new(Element).SqrtRatio(u, v)
-		if got.Equal(want) == 0 || wasSquare != tt.wasSquare {
-			t.Errorf("%d: got (%v, %v), want (%v, %v)", i, got, wasSquare, want, tt.wasSquare)
-		}
-	}
-}
-
-func TestCarryPropagate(t *testing.T) {
-	asmLikeGeneric := func(a [5]uint64) bool {
-		t1 := &Element{a[0], a[1], a[2], a[3], a[4]}
-		t2 := &Element{a[0], a[1], a[2], a[3], a[4]}
-
-		t1.carryPropagate()
-		t2.carryPropagateGeneric()
-
-		if *t1 != *t2 {
-			t.Logf("got: %#v,\nexpected: %#v", t1, t2)
-		}
-
-		return *t1 == *t2 && isInBounds(t2)
-	}
-
-	if err := quick.Check(asmLikeGeneric, quickCheckConfig1024); err != nil {
-		t.Error(err)
-	}
-
-	if !asmLikeGeneric([5]uint64{0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}) {
-		t.Errorf("failed for {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff}")
-	}
-}
-
-func TestFeSquare(t *testing.T) {
-	asmLikeGeneric := func(a Element) bool {
-		t1 := a
-		t2 := a
-
-		feSquareGeneric(&t1, &t1)
-		feSquare(&t2, &t2)
-
-		if t1 != t2 {
-			t.Logf("got: %#v,\nexpected: %#v", t1, t2)
-		}
-
-		return t1 == t2 && isInBounds(&t2)
-	}
-
-	if err := quick.Check(asmLikeGeneric, quickCheckConfig1024); err != nil {
-		t.Error(err)
-	}
-}
-
-func TestFeMul(t *testing.T) {
-	asmLikeGeneric := func(a, b Element) bool {
-		a1 := a
-		a2 := a
-		b1 := b
-		b2 := b
-
-		feMulGeneric(&a1, &a1, &b1)
-		feMul(&a2, &a2, &b2)
-
-		if a1 != a2 || b1 != b2 {
-			t.Logf("got: %#v,\nexpected: %#v", a1, a2)
-			t.Logf("got: %#v,\nexpected: %#v", b1, b2)
-		}
-
-		return a1 == a2 && isInBounds(&a2) &&
-			b1 == b2 && isInBounds(&b2)
-	}
-
-	if err := quick.Check(asmLikeGeneric, quickCheckConfig1024); err != nil {
-		t.Error(err)
-	}
-}
-
-func decodeHex(s string) []byte {
-	b, err := hex.DecodeString(s)
-	if err != nil {
-		panic(err)
-	}
-	return b
-}

curve25519/internal/field/sync.checkpoint

@@ -1 +0,0 @@
-b0c49ae9f59d233526f8934262c5bbbe14d4358d

curve25519/internal/field/sync.sh

@@ -1,19 +0,0 @@
-#! /bin/bash
-set -euo pipefail
-
-cd "$(git rev-parse --show-toplevel)"
-
-STD_PATH=src/crypto/ed25519/internal/edwards25519/field
-LOCAL_PATH=curve25519/internal/field
-LAST_SYNC_REF=$(cat $LOCAL_PATH/sync.checkpoint)
-
-git fetch https://go.googlesource.com/go master
-
-if git diff --quiet $LAST_SYNC_REF:$STD_PATH FETCH_HEAD:$STD_PATH; then
-    echo "No changes."
-else
-    NEW_REF=$(git rev-parse FETCH_HEAD | tee $LOCAL_PATH/sync.checkpoint)
-    echo "Applying changes from $LAST_SYNC_REF to $NEW_REF..."
-    git diff $LAST_SYNC_REF:$STD_PATH FETCH_HEAD:$STD_PATH | \
-        git apply -3 --directory=$LOCAL_PATH
-fi

curve25519/vectors_test.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.
 
-package curve25519
+package curve25519_test
 
 // lowOrderPoints from libsodium.
 // https://github.com/jedisct1/libsodium/blob/65621a1059a37d/src/libsodium/crypto_scalarmult/curve25519/ref10/x25519_ref10.c#L11-L70

ed25519/ed25519.go

@@ -11,9 +11,7 @@
 // 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.
+// This package is a wrapper around the standard library crypto/ed25519 package.
 package ed25519
 
 import (

go.mod

@@ -1,11 +1,11 @@
 module golang.org/x/crypto
 
-go 1.17
+go 1.20
 
 require (
-	golang.org/x/net v0.2.0
-	golang.org/x/sys v0.2.0
-	golang.org/x/term v0.2.0
+	golang.org/x/net v0.21.0 // tagx:ignore
+	golang.org/x/sys v0.23.0
+	golang.org/x/term v0.23.0
 )
 
-require golang.org/x/text v0.4.0 // indirect
+require golang.org/x/text v0.17.0 // indirect

go.sum

@@ -1,31 +1,8 @@
-github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20210921155107-089bfa567519/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
-golang.org/x/mod v0.6.0-dev.0.20220419223038-86c51ed26bb4/go.mod h1:jJ57K6gSWd91VN4djpZkiMVwK6gcyfeH4XE8wZrZaV4=
-golang.org/x/net v0.0.0-20190620200207-3b0461eec859/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
-golang.org/x/net v0.0.0-20210226172049-e18ecbb05110/go.mod h1:m0MpNAwzfU5UDzcl9v0D8zg8gWTRqZa9RBIspLL5mdg=
-golang.org/x/net v0.0.0-20220722155237-a158d28d115b/go.mod h1:XRhObCWvk6IyKnWLug+ECip1KBveYUHfp+8e9klMJ9c=
-golang.org/x/net v0.2.0 h1:sZfSu1wtKLGlWI4ZZayP0ck9Y73K1ynO6gqzTdBVdPU=
-golang.org/x/net v0.2.0/go.mod h1:KqCZLdyyvdV855qA2rE3GC2aiw5xGR5TEjj8smXukLY=
-golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sync v0.0.0-20220722155255-886fb9371eb4/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
-golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20201119102817-f84b799fce68/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20210615035016-665e8c7367d1/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220520151302-bc2c85ada10a/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.0.0-20220722155257-8c9f86f7a55f/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/sys v0.2.0 h1:ljd4t30dBnAvMZaQCevtY0xLLD0A+bRZXbgLMLU1F/A=
-golang.org/x/sys v0.2.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
-golang.org/x/term v0.0.0-20201126162022-7de9c90e9dd1/go.mod h1:bj7SfCRtBDWHUb9snDiAeCFNEtKQo2Wmx5Cou7ajbmo=
-golang.org/x/term v0.0.0-20210927222741-03fcf44c2211/go.mod h1:jbD1KX2456YbFQfuXm/mYQcufACuNUgVhRMnK/tPxf8=
-golang.org/x/term v0.2.0 h1:z85xZCsEl7bi/KwbNADeBYoOP0++7W1ipu+aGnpwzRM=
-golang.org/x/term v0.2.0/go.mod h1:TVmDHMZPmdnySmBfhjOoOdhjzdE1h4u1VwSiw2l1Nuc=
-golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
-golang.org/x/text v0.3.3/go.mod h1:5Zoc/QRtKVWzQhOtBMvqHzDpF6irO9z98xDceosuGiQ=
-golang.org/x/text v0.3.7/go.mod h1:u+2+/6zg+i71rQMx5EYifcz6MCKuco9NR6JIITiCfzQ=
-golang.org/x/text v0.4.0 h1:BrVqGRd7+k1DiOgtnFvAkoQEWQvBc25ouMJM6429SFg=
-golang.org/x/text v0.4.0/go.mod h1:mrYo+phRRbMaCq/xk9113O4dZlRixOauAjOtrjsXDZ8=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=
-golang.org/x/tools v0.0.0-20191119224855-298f0cb1881e/go.mod h1:b+2E5dAYhXwXZwtnZ6UAqBI28+e2cm9otk0dWdXHAEo=
-golang.org/x/tools v0.1.12/go.mod h1:hNGJHUnrk76NpqgfD5Aqm5Crs+Hm0VOH/i9J2+nxYbc=
-golang.org/x/xerrors v0.0.0-20190717185122-a985d3407aa7/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
+golang.org/x/net v0.21.0 h1:AQyQV4dYCvJ7vGmJyKki9+PBdyvhkSd8EIx/qb0AYv4=
+golang.org/x/net v0.21.0/go.mod h1:bIjVDfnllIU7BJ2DNgfnXvpSvtn8VRwhlsaeUTyUS44=
+golang.org/x/sys v0.23.0 h1:YfKFowiIMvtgl1UERQoTPPToxltDeZfbj4H7dVUCwmM=
+golang.org/x/sys v0.23.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
+golang.org/x/term v0.23.0 h1:F6D4vR+EHoL9/sWAWgAR1H2DcHr4PareCbAaCo1RpuU=
+golang.org/x/term v0.23.0/go.mod h1:DgV24QBUrK6jhZXl+20l6UWznPlwAHm1Q1mGHtydmSk=
+golang.org/x/text v0.17.0 h1:XtiM5bkSOt+ewxlOE/aE/AKEHibwj/6gvWMl9Rsh0Qc=
+golang.org/x/text v0.17.0/go.mod h1:BuEKDfySbSR4drPmRPG/7iBdf8hvFMuRexcpahXilzY=

hkdf/hkdf.go

@@ -8,7 +8,7 @@
 // HKDF is a cryptographic key derivation function (KDF) with the goal of
 // expanding limited input keying material into one or more cryptographically
 // strong secret keys.
-package hkdf // import "golang.org/x/crypto/hkdf"
+package hkdf
 
 import (
 	"crypto/hmac"
@@ -56,7 +56,9 @@ func (f *hkdf) Read(p []byte) (int, error) {
 
 	// Fill the rest of the buffer
 	for len(p) > 0 {
-		f.expander.Reset()
+		if f.counter > 1 {
+			f.expander.Reset()
+		}
 		f.expander.Write(f.prev)
 		f.expander.Write(f.info)
 		f.expander.Write([]byte{f.counter})

internal/alias/alias.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build !purego
-// +build !purego
 
 // Package alias implements memory aliasing tests.
 package alias

internal/alias/alias_purego.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build purego
-// +build purego
 
 // Package alias implements memory aliasing tests.
 package alias

internal/poly1305/bits_compat.go

@@ -1,40 +0,0 @@
-// 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.
-
-//go:build !go1.13
-// +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
-}

internal/poly1305/bits_go1.13.go

@@ -1,22 +0,0 @@
-// 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.
-
-//go:build go1.13
-// +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)
-}

internal/poly1305/mac_noasm.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build (!amd64 && !ppc64le && !s390x) || !gc || purego
-// +build !amd64,!ppc64le,!s390x !gc purego
 
 package poly1305
 

internal/poly1305/sum_amd64.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 package poly1305
 

internal/poly1305/sum_amd64.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 #include "textflag.h"
 

internal/poly1305/sum_generic.go

@@ -7,7 +7,10 @@
 
 package poly1305
 
-import "encoding/binary"
+import (
+	"encoding/binary"
+	"math/bits"
+)
 
 // Poly1305 [RFC 7539] is a relatively simple algorithm: the authentication tag
 // for a 64 bytes message is approximately
@@ -114,13 +117,13 @@ type uint128 struct {
 }
 
 func mul64(a, b uint64) uint128 {
-	hi, lo := bitsMul64(a, b)
+	hi, lo := bits.Mul64(a, b)
 	return uint128{lo, hi}
 }
 
 func add128(a, b uint128) uint128 {
-	lo, c := bitsAdd64(a.lo, b.lo, 0)
-	hi, c := bitsAdd64(a.hi, b.hi, c)
+	lo, c := bits.Add64(a.lo, b.lo, 0)
+	hi, c := bits.Add64(a.hi, b.hi, c)
 	if c != 0 {
 		panic("poly1305: unexpected overflow")
 	}
@@ -155,8 +158,8 @@ func updateGeneric(state *macState, msg []byte) {
 		// 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)
+			h0, c = bits.Add64(h0, binary.LittleEndian.Uint64(msg[0:8]), 0)
+			h1, c = bits.Add64(h1, binary.LittleEndian.Uint64(msg[8:16]), c)
 			h2 += c + 1
 
 			msg = msg[TagSize:]
@@ -165,8 +168,8 @@ func updateGeneric(state *macState, msg []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)
+			h0, c = bits.Add64(h0, binary.LittleEndian.Uint64(buf[0:8]), 0)
+			h1, c = bits.Add64(h1, binary.LittleEndian.Uint64(buf[8:16]), c)
 			h2 += c
 
 			msg = nil
@@ -219,9 +222,9 @@ func updateGeneric(state *macState, msg []byte) {
 		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)
+		t1, c := bits.Add64(m1.lo, m0.hi, 0)
+		t2, c := bits.Add64(m2.lo, m1.hi, c)
+		t3, _ := bits.Add64(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
@@ -243,14 +246,14 @@ func updateGeneric(state *macState, msg []byte) {
 
 		// 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)
+		h0, c = bits.Add64(h0, cc.lo, 0)
+		h1, c = bits.Add64(h1, cc.hi, c)
 		h2 += c
 
 		cc = shiftRightBy2(cc)
 
-		h0, c = bitsAdd64(h0, cc.lo, 0)
-		h1, c = bitsAdd64(h1, cc.hi, c)
+		h0, c = bits.Add64(h0, cc.lo, 0)
+		h1, c = bits.Add64(h1, cc.hi, c)
 		h2 += c
 
 		// h2 is at most 3 + 1 + 1 = 5, making the whole of h at most
@@ -287,9 +290,9 @@ func finalize(out *[TagSize]byte, h *[3]uint64, s *[2]uint64) {
 	// in constant time, we compute t = h - (2¹³⁰ - 5), and select h as the
 	// result if the subtraction underflows, and t otherwise.
 
-	hMinusP0, b := bitsSub64(h0, p0, 0)
-	hMinusP1, b := bitsSub64(h1, p1, b)
-	_, b = bitsSub64(h2, p2, b)
+	hMinusP0, b := bits.Sub64(h0, p0, 0)
+	hMinusP1, b := bits.Sub64(h1, p1, b)
+	_, b = bits.Sub64(h2, p2, b)
 
 	// h = h if h < p else h - p
 	h0 = select64(b, h0, hMinusP0)
@@ -301,8 +304,8 @@ func finalize(out *[TagSize]byte, h *[3]uint64, s *[2]uint64) {
 	//
 	// 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)
+	h0, c := bits.Add64(h0, s[0], 0)
+	h1, _ = bits.Add64(h1, s[1], c)
 
 	binary.LittleEndian.PutUint64(out[0:8], h0)
 	binary.LittleEndian.PutUint64(out[8:16], h1)

internal/poly1305/sum_ppc64le.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 package poly1305
 

internal/poly1305/sum_ppc64le.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 #include "textflag.h"
 
@@ -20,15 +19,14 @@
 
 #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;  \
+	MULLD  r0, h1, t4;  \
 	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;  \
+	ADDE   t5, t2, t2;  \
 	ADDC   h0, t1, t1;  \
 	MULLD  h2, r1, t3;  \
 	ADDZE  t4, h0;      \
@@ -38,13 +36,11 @@
 	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;  \
+	RLDICL $0, t2, $62, h2; \
+	AND    t2, t4, h0;  \
 	ADDC   t0, h0, h0;  \
-	ADDE   t3, h1, h1;  \
+	ADDE   t3, t1, h1;  \
 	SLD    $62, t3, t4; \
 	SRD    $2, t2;      \
 	ADDZE  h2;          \
@@ -76,6 +72,7 @@ TEXT ·update(SB), $0-32
 loop:
 	POLY1305_ADD(R4, R8, R9, R10, R20, R21, R22)
 
+	PCALIGN $16
 multiply:
 	POLY1305_MUL(R8, R9, R10, R11, R12, R16, R17, R18, R14, R20, R21)
 	ADD $-16, R5

internal/poly1305/sum_s390x.go

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 package poly1305
 

internal/poly1305/sum_s390x.s

@@ -3,7 +3,6 @@
 // license that can be found in the LICENSE file.
 
 //go:build gc && !purego
-// +build gc,!purego
 
 #include "textflag.h"
 

internal/testenv/exec.go

@@ -0,0 +1,120 @@
+// Copyright 2023 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 testenv
+
+import (
+	"context"
+	"os"
+	"os/exec"
+	"reflect"
+	"strconv"
+	"testing"
+	"time"
+)
+
+// CommandContext is like exec.CommandContext, but:
+//   - skips t if the platform does not support os/exec,
+//   - sends SIGQUIT (if supported by the platform) instead of SIGKILL
+//     in its Cancel function
+//   - if the test has a deadline, adds a Context timeout and WaitDelay
+//     for an arbitrary grace period before the test's deadline expires,
+//   - fails the test if the command does not complete before the test's deadline, and
+//   - sets a Cleanup function that verifies that the test did not leak a subprocess.
+func CommandContext(t testing.TB, ctx context.Context, name string, args ...string) *exec.Cmd {
+	t.Helper()
+
+	var (
+		cancelCtx   context.CancelFunc
+		gracePeriod time.Duration // unlimited unless the test has a deadline (to allow for interactive debugging)
+	)
+
+	if t, ok := t.(interface {
+		testing.TB
+		Deadline() (time.Time, bool)
+	}); ok {
+		if td, ok := t.Deadline(); ok {
+			// Start with a minimum grace period, just long enough to consume the
+			// output of a reasonable program after it terminates.
+			gracePeriod = 100 * time.Millisecond
+			if s := os.Getenv("GO_TEST_TIMEOUT_SCALE"); s != "" {
+				scale, err := strconv.Atoi(s)
+				if err != nil {
+					t.Fatalf("invalid GO_TEST_TIMEOUT_SCALE: %v", err)
+				}
+				gracePeriod *= time.Duration(scale)
+			}
+
+			// If time allows, increase the termination grace period to 5% of the
+			// test's remaining time.
+			testTimeout := time.Until(td)
+			if gp := testTimeout / 20; gp > gracePeriod {
+				gracePeriod = gp
+			}
+
+			// When we run commands that execute subprocesses, we want to reserve two
+			// grace periods to clean up: one for the delay between the first
+			// termination signal being sent (via the Cancel callback when the Context
+			// expires) and the process being forcibly terminated (via the WaitDelay
+			// field), and a second one for the delay between the process being
+			// terminated and the test logging its output for debugging.
+			//
+			// (We want to ensure that the test process itself has enough time to
+			// log the output before it is also terminated.)
+			cmdTimeout := testTimeout - 2*gracePeriod
+
+			if cd, ok := ctx.Deadline(); !ok || time.Until(cd) > cmdTimeout {
+				// Either ctx doesn't have a deadline, or its deadline would expire
+				// after (or too close before) the test has already timed out.
+				// Add a shorter timeout so that the test will produce useful output.
+				ctx, cancelCtx = context.WithTimeout(ctx, cmdTimeout)
+			}
+		}
+	}
+
+	cmd := exec.CommandContext(ctx, name, args...)
+	// Set the Cancel and WaitDelay fields only if present (go 1.20 and later).
+	// TODO: When Go 1.19 is no longer supported, remove this use of reflection
+	// and instead set the fields directly.
+	if cmdCancel := reflect.ValueOf(cmd).Elem().FieldByName("Cancel"); cmdCancel.IsValid() {
+		cmdCancel.Set(reflect.ValueOf(func() error {
+			if cancelCtx != nil && ctx.Err() == context.DeadlineExceeded {
+				// The command timed out due to running too close to the test's deadline.
+				// There is no way the test did that intentionally — it's too close to the
+				// wire! — so mark it as a test failure. That way, if the test expects the
+				// command to fail for some other reason, it doesn't have to distinguish
+				// between that reason and a timeout.
+				t.Errorf("test timed out while running command: %v", cmd)
+			} else {
+				// The command is being terminated due to ctx being canceled, but
+				// apparently not due to an explicit test deadline that we added.
+				// Log that information in case it is useful for diagnosing a failure,
+				// but don't actually fail the test because of it.
+				t.Logf("%v: terminating command: %v", ctx.Err(), cmd)
+			}
+			return cmd.Process.Signal(Sigquit)
+		}))
+	}
+	if cmdWaitDelay := reflect.ValueOf(cmd).Elem().FieldByName("WaitDelay"); cmdWaitDelay.IsValid() {
+		cmdWaitDelay.Set(reflect.ValueOf(gracePeriod))
+	}
+
+	t.Cleanup(func() {
+		if cancelCtx != nil {
+			cancelCtx()
+		}
+		if cmd.Process != nil && cmd.ProcessState == nil {
+			t.Errorf("command was started, but test did not wait for it to complete: %v", cmd)
+		}
+	})
+
+	return cmd
+}
+
+// Command is like exec.Command, but applies the same changes as
+// testenv.CommandContext (with a default Context).
+func Command(t testing.TB, name string, args ...string) *exec.Cmd {
+	t.Helper()
+	return CommandContext(t, context.Background(), name, args...)
+}

internal/testenv/testenv_notunix.go

@@ -0,0 +1,15 @@
+// Copyright 2021 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.
+
+//go:build windows || plan9 || (js && wasm) || wasip1
+
+package testenv
+
+import (
+	"os"
+)
+
+// Sigquit is the signal to send to kill a hanging subprocess.
+// On Unix we send SIGQUIT, but on non-Unix we only have os.Kill.
+var Sigquit = os.Kill

internal/testenv/testenv_unix.go

@@ -0,0 +1,15 @@
+// Copyright 2021 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.
+
+//go:build unix
+
+package testenv
+
+import (
+	"syscall"
+)
+
+// Sigquit is the signal to send to kill a hanging subprocess.
+// Send SIGQUIT to get a stack trace.
+var Sigquit = syscall.SIGQUIT

internal/wycheproof/ecdh_stdlib_test.go

@@ -2,8 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.20
-
 package wycheproof
 
 import (

internal/wycheproof/ecdsa_test.go

@@ -6,7 +6,11 @@ package wycheproof
 
 import (
 	"crypto/ecdsa"
+	"math/big"
 	"testing"
+
+	"golang.org/x/crypto/cryptobyte"
+	"golang.org/x/crypto/cryptobyte/asn1"
 )
 
 func TestECDSA(t *testing.T) {
@@ -76,9 +80,25 @@ func TestECDSA(t *testing.T) {
 			h.Reset()
 			h.Write(decodeHex(sig.Msg))
 			hashed := h.Sum(nil)
-			got := ecdsa.VerifyASN1(pub, hashed, decodeHex(sig.Sig))
+			sigBytes := decodeHex(sig.Sig)
+			got := ecdsa.VerifyASN1(pub, hashed, sigBytes)
 			if want := shouldPass(sig.Result, sig.Flags, flagsShouldPass); got != want {
-				t.Errorf("tcid: %d, type: %s, comment: %q, wanted success: %t", sig.TcID, sig.Result, sig.Comment, want)
+				t.Errorf("tcid: %d, type: %s, comment: %q, VerifyASN1 wanted success: %t", sig.TcID, sig.Result, sig.Comment, want)
+			}
+
+			var r, s big.Int
+			var inner cryptobyte.String
+			input := cryptobyte.String(sigBytes)
+			if !input.ReadASN1(&inner, asn1.SEQUENCE) ||
+				!input.Empty() ||
+				!inner.ReadASN1Integer(&r) ||
+				!inner.ReadASN1Integer(&s) ||
+				!inner.Empty() {
+				continue
+			}
+			got = ecdsa.Verify(pub, hashed, &r, &s)
+			if want := shouldPass(sig.Result, sig.Flags, flagsShouldPass); got != want {
+				t.Errorf("tcid: %d, type: %s, comment: %q, Verify wanted success: %t", sig.TcID, sig.Result, sig.Comment, want)
 			}
 		}
 	}

internal/wycheproof/eddsa_test.go

@@ -2,15 +2,11 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.13
-// +build go1.13
-
 package wycheproof
 
 import (
+	"crypto/ed25519"
 	"testing"
-
-	"golang.org/x/crypto/ed25519"
 )
 
 func TestEddsa(t *testing.T) {

internal/wycheproof/wycheproof_test.go

@@ -11,6 +11,7 @@ import (
 	"crypto/x509"
 	"encoding/hex"
 	"encoding/json"
+	"flag"
 	"fmt"
 	"log"
 	"os"
@@ -28,6 +29,11 @@ const wycheproofModVer = "v0.0.0-20191219022705-2196000605e4"
 var wycheproofTestVectorsDir string
 
 func TestMain(m *testing.M) {
+	flag.Parse()
+	if flag.Lookup("test.short").Value.(flag.Getter).Get().(bool) {
+		log.Println("skipping test that downloads testdata via 'go mod download' in short mode")
+		os.Exit(0)
+	}
 	if _, err := exec.LookPath("go"); err != nil {
 		log.Printf("skipping test because 'go' command is unavailable: %v", err)
 		os.Exit(0)
@@ -42,8 +48,6 @@ func TestMain(m *testing.M) {
 	// can be used in the following tests.
 	path := "github.com/google/wycheproof@" + wycheproofModVer
 	cmd := exec.Command("go", "mod", "download", "-json", path)
-	// TODO: enable the sumdb once the Trybots proxy supports it.
-	cmd.Env = append(os.Environ(), "GONOSUMDB=*")
 	output, err := cmd.Output()
 	if err != nil {
 		log.Fatalf("failed to run `go mod download -json %s`, output: %s", path, output)

md4/md4.go

@@ -4,10 +4,10 @@
 
 // Package md4 implements the MD4 hash algorithm as defined in RFC 1320.
 //
-// Deprecated: MD4 is cryptographically broken and should should only be used
+// Deprecated: MD4 is cryptographically broken and should only be used
 // where compatibility with legacy systems, not security, is the goal. Instead,
 // use a secure hash like SHA-256 (from crypto/sha256).
-package md4 // import "golang.org/x/crypto/md4"
+package md4
 
 import (
 	"crypto"

nacl/box/box.go

@@ -35,7 +35,7 @@ Anonymous sealing/opening is an extension of NaCl defined by and interoperable
 with libsodium:
 https://libsodium.gitbook.io/doc/public-key_cryptography/sealed_boxes.
 */
-package box // import "golang.org/x/crypto/nacl/box"
+package box
 
 import (
 	cryptorand "crypto/rand"

nacl/secretbox/secretbox.go

@@ -32,7 +32,7 @@ chunk size.
 
 This package is interoperable with NaCl: https://nacl.cr.yp.to/secretbox.html.
 */
-package secretbox // import "golang.org/x/crypto/nacl/secretbox"
+package secretbox
 
 import (
 	"golang.org/x/crypto/internal/alias"

nacl/sign/sign.go

@@ -21,9 +21,9 @@
 package sign
 
 import (
+	"crypto/ed25519"
 	"io"
 
-	"golang.org/x/crypto/ed25519"
 	"golang.org/x/crypto/internal/alias"
 )
 

ocsp/ocsp.go

@@ -5,7 +5,7 @@
 // Package ocsp parses OCSP responses as specified in RFC 2560. OCSP responses
 // are signed messages attesting to the validity of a certificate for a small
 // period of time. This is used to manage revocation for X.509 certificates.
-package ocsp // import "golang.org/x/crypto/ocsp"
+package ocsp
 
 import (
 	"crypto"
@@ -279,21 +279,22 @@ func getOIDFromHashAlgorithm(target crypto.Hash) asn1.ObjectIdentifier {
 
 // This is the exposed reflection of the internal OCSP structures.
 
-// The status values that can be expressed in OCSP.  See RFC 6960.
+// The status values that can be expressed in OCSP. See RFC 6960.
+// These are used for the Response.Status field.
 const (
 	// Good means that the certificate is valid.
-	Good = iota
+	Good = 0
 	// Revoked means that the certificate has been deliberately revoked.
-	Revoked
+	Revoked = 1
 	// Unknown means that the OCSP responder doesn't know about the certificate.
-	Unknown
+	Unknown = 2
 	// ServerFailed is unused and was never used (see
 	// https://go-review.googlesource.com/#/c/18944). ParseResponse will
 	// return a ResponseError when an error response is parsed.
-	ServerFailed
+	ServerFailed = 3
 )
 
-// The enumerated reasons for revoking a certificate.  See RFC 5280.
+// The enumerated reasons for revoking a certificate. See RFC 5280.
 const (
 	Unspecified          = 0
 	KeyCompromise        = 1

ocsp/ocsp_test.go

@@ -2,9 +2,6 @@
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.
 
-//go:build go1.7
-// +build go1.7
-
 package ocsp
 
 import (

openpgp/armor/armor.go

@@ -10,14 +10,15 @@
 // for their specific task. If you are required to interoperate with OpenPGP
 // systems and need a maintained package, consider a community fork.
 // See https://golang.org/issue/44226.
-package armor // import "golang.org/x/crypto/openpgp/armor"
+package armor
 
 import (
 	"bufio"
 	"bytes"
 	"encoding/base64"
-	"golang.org/x/crypto/openpgp/errors"
 	"io"
+
+	"golang.org/x/crypto/openpgp/errors"
 )
 
 // A Block represents an OpenPGP armored structure.

openpgp/clearsign/clearsign.go

@@ -13,7 +13,7 @@
 // for their specific task. If you are required to interoperate with OpenPGP
 // systems and need a maintained package, consider a community fork.
 // See https://golang.org/issue/44226.
-package clearsign // import "golang.org/x/crypto/openpgp/clearsign"
+package clearsign
 
 import (
 	"bufio"

openpgp/elgamal/elgamal.go

@@ -16,7 +16,7 @@
 // https://golang.org/issue/44226), and ElGamal in the OpenPGP ecosystem has
 // compatibility and security issues (see https://eprint.iacr.org/2021/923).
 // Moreover, this package doesn't protect against side-channel attacks.
-package elgamal // import "golang.org/x/crypto/openpgp/elgamal"
+package elgamal
 
 import (
 	"crypto/rand"

openpgp/errors/errors.go

@@ -9,7 +9,7 @@
 // for their specific task. If you are required to interoperate with OpenPGP
 // systems and need a maintained package, consider a community fork.
 // See https://golang.org/issue/44226.
-package errors // import "golang.org/x/crypto/openpgp/errors"
+package errors
 
 import (
 	"strconv"

openpgp/keys.go

@@ -61,7 +61,7 @@ type Key struct {
 type KeyRing interface {
 	// KeysById returns the set of keys that have the given key id.
 	KeysById(id uint64) []Key
-	// KeysByIdAndUsage returns the set of keys with the given id
+	// KeysByIdUsage returns the set of keys with the given id
 	// that also meet the key usage given by requiredUsage.
 	// The requiredUsage is expressed as the bitwise-OR of
 	// packet.KeyFlag* values.
@@ -183,7 +183,7 @@ func (el EntityList) KeysById(id uint64) (keys []Key) {
 	return
 }
 
-// KeysByIdAndUsage returns the set of keys with the given id that also meet
+// KeysByIdUsage returns the set of keys with the given id that also meet
 // the key usage given by requiredUsage.  The requiredUsage is expressed as
 // the bitwise-OR of packet.KeyFlag* values.
 func (el EntityList) KeysByIdUsage(id uint64, requiredUsage byte) (keys []Key) {

openpgp/keys_test.go

@@ -132,7 +132,7 @@ func TestRevokedUserID(t *testing.T) {
 	}
 }
 
-// TestExternallyRevokableKey attempts to load and parse a key with a third party revocation permission.
+// TestExternallyRevocableKey attempts to load and parse a key with a third party revocation permission.
 func TestExternallyRevocableKey(t *testing.T) {
 	kring, err := ReadKeyRing(readerFromHex(subkeyUsageHex))
 	if err != nil {