[dev.boringcrypto] all: merge master (nearly Go 1.10 beta 1) into dev.boringcrypto

This is a git merge of master into dev.boringcrypto.

The branch was previously based on release-branch.go1.9,
so there are a handful of spurious conflicts that would
also arise if trying to merge master into release-branch.go1.9
(which we never do). Those have all been resolved by taking
the original file from master, discarding any Go 1.9-specific
edits.

all.bash passes on darwin/amd64, which is to say without
actually using BoringCrypto.

Go 1.10-related fixes to BoringCrypto itself will be in a followup CL.
This CL is just the merge.

Change-Id: I4c97711fec0fb86761913dcde28d25c001246c35

1 files changed, 10 insertions, 9 deletions

diff --git a/src/crypto/rsa/rsa.go b/src/crypto/rsa/rsa.go
index 8e63185ec6..9af5cbb165 100644
--- a/src/crypto/rsa/rsa.go
+++ b/src/crypto/rsa/rsa.go
@@ -98,17 +98,19 @@ func (priv *PrivateKey) Public() crypto.PublicKey {
 	return &priv.PublicKey
 }
 
-// Sign signs msg with priv, reading randomness from rand. If opts is a
+// Sign signs digest with priv, reading randomness from rand. If opts is a
 // *PSSOptions then the PSS algorithm will be used, otherwise PKCS#1 v1.5 will
-// be used. This method is intended to support keys where the private part is
-// kept in, for example, a hardware module. Common uses should use the Sign*
-// functions in this package.
-func (priv *PrivateKey) Sign(rand io.Reader, msg []byte, opts crypto.SignerOpts) ([]byte, error) {
+// be used.
+//
+// This method implements crypto.Signer, which is an interface to support keys
+// where the private part is kept in, for example, a hardware module. Common
+// uses should use the Sign* functions in this package directly.
+func (priv *PrivateKey) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
 	if pssOpts, ok := opts.(*PSSOptions); ok {
-		return SignPSS(rand, priv, pssOpts.Hash, msg, pssOpts)
+		return SignPSS(rand, priv, pssOpts.Hash, digest, pssOpts)
 	}
 
-	return SignPKCS1v15(rand, priv, opts.HashFunc(), msg)
+	return SignPKCS1v15(rand, priv, opts.HashFunc(), digest)
 }
 
 // Decrypt decrypts ciphertext with priv. If opts is nil or of type
@@ -480,8 +482,7 @@ var ErrVerification = errors.New("crypto/rsa: verification error")
 func modInverse(a, n *big.Int) (ia *big.Int, ok bool) {
 	g := new(big.Int)
 	x := new(big.Int)
-	y := new(big.Int)
-	g.GCD(x, y, a, n)
+	g.GCD(x, nil, a, n)
 	if g.Cmp(bigOne) != 0 {
 		// In this case, a and n aren't coprime and we cannot calculate
 		// the inverse. This happens because the values of n are nearly