patches: restore signature of HashSign/HashVerify (#199)

Co-authored-by: Derek Parker <[email protected]>

patches/015-add-hash-sign-verify.patch

@@ -1,20 +1,54 @@
 diff --git a/src/crypto/ecdsa/ecdsa_hash_sign_verify.go b/src/crypto/ecdsa/ecdsa_hash_sign_verify.go
 new file mode 100644
-index 0000000000..50a39f5d0a
+index 0000000000..977b21958f
 --- /dev/null
 +++ b/src/crypto/ecdsa/ecdsa_hash_sign_verify.go
-@@ -0,0 +1,45 @@
+@@ -0,0 +1,96 @@
 +package ecdsa
 +
 +import (
 +	"crypto"
 +	"crypto/internal/randutil"
++	"errors"
 +	"io"
++	"math/big"
 +
 +	boring "crypto/internal/backend"
++
++	"golang.org/x/crypto/cryptobyte"
++	"golang.org/x/crypto/cryptobyte/asn1"
 +)
 +
-+func HashSign(rand io.Reader, priv *PrivateKey, msg []byte, h crypto.Hash) ([]byte, error) {
++func HashSign(rand io.Reader, priv *PrivateKey, msg []byte, h crypto.Hash) (*big.Int, *big.Int, error) {
++	randutil.MaybeReadByte(rand)
++
++	if boring.Enabled() {
++		sig, err := HashSignASN1(rand, priv, msg, h)
++		if err != nil {
++			return nil, nil, err
++		}
++		r, s := new(big.Int), new(big.Int)
++		var inner cryptobyte.String
++		input := cryptobyte.String(sig)
++		if !input.ReadASN1(&inner, asn1.SEQUENCE) ||
++			!input.Empty() ||
++			!inner.ReadASN1Integer(r) ||
++			!inner.ReadASN1Integer(s) ||
++			!inner.Empty() {
++			return nil, nil, errors.New("invalid ASN.1 from HashSignECDSA")
++		}
++		return r, s, nil
++	}
++	boring.UnreachableExceptTests()
++
++	hash := h.New()
++	hash.Write(msg)
++	d := hash.Sum(nil)
++
++	return Sign(rand, priv, d)
++}
++
++func HashSignASN1(rand io.Reader, priv *PrivateKey, msg []byte, h crypto.Hash) ([]byte, error) {
 +	randutil.MaybeReadByte(rand)
 +
 +	if boring.Enabled() {
@@ -33,7 +67,24 @@ index 0000000000..50a39f5d0a
 +	return SignASN1(rand, priv, d)
 +}
 +
-+func HashVerify(pub *PublicKey, msg, sig []byte, h crypto.Hash) bool {
++func HashVerify(pub *PublicKey, msg []byte, r, s *big.Int, h crypto.Hash) bool {
++	if boring.Enabled() {
++		sig, err := encodeSignature(r.Bytes(), s.Bytes())
++		if err != nil {
++			return false
++		}
++		return HashVerifyASN1(pub, h, msg, sig)
++	}
++	boring.UnreachableExceptTests()
++
++	hash := h.New()
++	hash.Write(msg)
++	d := hash.Sum(nil)
++
++	return Verify(pub, d, r, s)
++}
++
++func HashVerifyASN1(pub *PublicKey, h crypto.Hash, msg, sig []byte) bool {
 +	if boring.Enabled() {
 +		bpk, err := boringPublicKey(pub)
 +		if err != nil {
@@ -51,7 +102,7 @@ index 0000000000..50a39f5d0a
 +}
 diff --git a/src/crypto/ecdsa/ecdsa_hashsignverify_test.go b/src/crypto/ecdsa/ecdsa_hashsignverify_test.go
 new file mode 100644
-index 0000000000..65ca8a4b77
+index 0000000000..b73b03e975
 --- /dev/null
 +++ b/src/crypto/ecdsa/ecdsa_hashsignverify_test.go
 @@ -0,0 +1,43 @@
@@ -73,23 +124,23 @@ index 0000000000..65ca8a4b77
 +
 +	msg := []byte("testing")
 +	h := crypto.SHA256
-+	hsm, err := HashSign(rand.Reader, priv, msg, h)
++	hsm, err := HashSignASN1(rand.Reader, priv, msg, h)
 +	if err != nil {
 +		t.Errorf("%s: error signing: %s", tag, err)
 +		return
 +	}
 +
-+	if !HashVerify(&priv.PublicKey, msg, hsm, h) {
++	if !HashVerifyASN1(&priv.PublicKey, h, msg, hsm) {
 +		t.Errorf("%s: Verify failed", tag)
 +	}
 +
 +	msg[0] ^= 0xff
-+	if HashVerify(&priv.PublicKey, msg, hsm, h) {
++	if HashVerifyASN1(&priv.PublicKey, h, msg, hsm) {
 +		t.Errorf("%s: Verify should not have succeeded", tag)
 +	}
 +}
 +
-+func TestHashSignAndHashVerify(t *testing.T) {
++func TestHashSignAndHashVerifyASN1(t *testing.T) {
 +	testHashSignAndHashVerify(t, elliptic.P256(), "p256")
 +
 +	if testing.Short() && !boring.Enabled() {