libgo: update to Go 1.11

    
    Reviewed-on: https://go-review.googlesource.com/136435

gotools/:
	* Makefile.am (mostlyclean-local): Run chmod on check-go-dir to
	make sure it is writable.
	(check-go-tools): Likewise.
	(check-vet): Copy internal/objabi to check-vet-dir.
	* Makefile.in: Rebuild.

From-SVN: r264546

3 files changed, 39 insertions, 1 deletions

diff --git a/libgo/go/crypto/ecdsa/ecdsa.go b/libgo/go/crypto/ecdsa/ecdsa.go
index 755ed28..2bab14c 100644
--- a/libgo/go/crypto/ecdsa/ecdsa.go
+++ b/libgo/go/crypto/ecdsa/ecdsa.go
@@ -26,6 +26,8 @@ import (
 	"errors"
 	"io"
 	"math/big"
+
+	"crypto/internal/randutil"
 )
 
 // A invertible implements fast inverse mod Curve.Params().N
@@ -152,6 +154,8 @@ var errZeroParam = errors.New("zero parameter")
 // returns the signature as a pair of integers. The security of the private key
 // depends on the entropy of rand.
 func Sign(rand io.Reader, priv *PrivateKey, hash []byte) (r, s *big.Int, err error) {
+	randutil.MaybeReadByte(rand)
+
 	// Get min(log2(q) / 2, 256) bits of entropy from rand.
 	entropylen := (priv.Curve.Params().BitSize + 7) / 16
 	if entropylen > 32 {
diff --git a/libgo/go/crypto/ecdsa/ecdsa_test.go b/libgo/go/crypto/ecdsa/ecdsa_test.go
index 9224a03..6284e06 100644
--- a/libgo/go/crypto/ecdsa/ecdsa_test.go
+++ b/libgo/go/crypto/ecdsa/ecdsa_test.go
@@ -213,7 +213,7 @@ func fromHex(s string) *big.Int {
 
 func TestVectors(t *testing.T) {
 	// This test runs the full set of NIST test vectors from
-	// http://csrc.nist.gov/groups/STM/cavp/documents/dss/186-3ecdsatestvectors.zip
+	// https://csrc.nist.gov/groups/STM/cavp/documents/dss/186-3ecdsatestvectors.zip
 	//
 	// The SigVer.rsp file has been edited to remove test vectors for
 	// unsupported algorithms and has been compressed.
diff --git a/libgo/go/crypto/ecdsa/example_test.go b/libgo/go/crypto/ecdsa/example_test.go
new file mode 100644
index 0000000..7c7fb1b
--- /dev/null
+++ b/libgo/go/crypto/ecdsa/example_test.go
@@ -0,0 +1,34 @@
+// Copyright 2018 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// +build gccgo_examples
+
+package ecdsa_test
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/sha256"
+	"fmt"
+)
+
+func Example() {
+	privateKey, err := ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	if err != nil {
+		panic(err)
+	}
+
+	msg := "hello, world"
+	hash := sha256.Sum256([]byte(msg))
+
+	r, s, err := ecdsa.Sign(rand.Reader, privateKey, hash[:])
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("signature: (0x%x, 0x%x)\n", r, s)
+
+	valid := ecdsa.Verify(&privateKey.PublicKey, hash[:], r, s)
+	fmt.Println("signature verified:", valid)
+}