go.cypherpunks.ru namespace usage

[gogost.git] / gost3410 / vko2012.go

diff --git a/gost3410/vko2012.go b/gost3410/vko2012.go
new file mode 100644 (file)
index 0000000..7a30b4e
--- /dev/null
+++ b/gost3410/vko2012.go
@@ -0,0 +1,47 @@
+// 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, version 3 of the License.
+//
+// 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 (
+       "math/big"
+
+       "go.cypherpunks.ru/gogost/v4/gost34112012256"
+       "go.cypherpunks.ru/gogost/v4/gost34112012512"
+)
+
+// RFC 7836 VKO GOST R 34.10-2012 256-bit key agreement function.
+// UKM is user keying material, also called VKO-factor.
+func (prv *PrivateKey) KEK2012256(pub *PublicKey, ukm *big.Int) ([]byte, error) {
+       key, err := prv.KEK(pub, ukm)
+       if err != nil {
+               return nil, err
+       }
+       h := gost34112012256.New()
+       h.Write(key)
+       return h.Sum(key[:0]), nil
+}
+
+// RFC 7836 VKO GOST R 34.10-2012 512-bit key agreement function.
+// UKM is user keying material, also called VKO-factor.
+func (prv *PrivateKey) KEK2012512(pub *PublicKey, ukm *big.Int) ([]byte, error) {
+       key, err := prv.KEK(pub, ukm)
+       if err != nil {
+               return nil, err
+       }
+       h := gost34112012512.New()
+       h.Write(key)
+       return h.Sum(key[:0]), nil
+}