From 4c6ef47b160219dafbddd213694188574a432d9f Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 26 Jul 2019 16:54:12 +0300
Subject: [PATCH] gost3410.PrivateKey satisfies crypto.Signer interface

---
 src/cypherpunks.ru/gogost/gost3410/private.go | 13 ++++++++
 .../gogost/gost3410/private_test.go           | 33 +++++++++++++++++++
 2 files changed, 46 insertions(+)
 create mode 100644 src/cypherpunks.ru/gogost/gost3410/private_test.go

diff --git a/src/cypherpunks.ru/gogost/gost3410/private.go b/src/cypherpunks.ru/gogost/gost3410/private.go
index 03fd443..e445cfd 100644
--- a/src/cypherpunks.ru/gogost/gost3410/private.go
+++ b/src/cypherpunks.ru/gogost/gost3410/private.go
@@ -17,6 +17,7 @@
 package gost3410
 
 import (
+	"crypto"
 	"errors"
 	"io"
 	"math/big"
@@ -106,3 +107,15 @@ Retry:
 		pad(r.Bytes(), int(prv.Mode))...,
 	), nil
 }
+
+func (prv *PrivateKey) Sign(rand io.Reader, digest []byte, opts crypto.SignerOpts) ([]byte, error) {
+	return prv.SignDigest(digest, rand)
+}
+
+func (prv *PrivateKey) Public() crypto.PublicKey {
+	pub, err := prv.PublicKey()
+	if err != nil {
+		panic(err)
+	}
+	return pub
+}
diff --git a/src/cypherpunks.ru/gogost/gost3410/private_test.go b/src/cypherpunks.ru/gogost/gost3410/private_test.go
new file mode 100644
index 0000000..40c62d3
--- /dev/null
+++ b/src/cypherpunks.ru/gogost/gost3410/private_test.go
@@ -0,0 +1,33 @@
+// GoGOST -- Pure Go GOST cryptographic functions library
+// Copyright (C) 2015-2019 Sergey Matveev <stargrave@stargrave.org>
+//
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+package gost3410
+
+import (
+	"crypto"
+	"crypto/rand"
+	"testing"
+)
+
+func TestSignerInterface(t *testing.T) {
+	prvRaw := make([]byte, int(Mode2001))
+	rand.Read(prvRaw)
+	prv, err := NewPrivateKey(CurveIdGostR34102001TestParamSet(), Mode2001, prvRaw)
+	if err != nil {
+		t.FailNow()
+	}
+	var _ crypto.Signer = prv
+}
-- 
2.44.0