From 107600dede989f0cc479b5a72c5f97e174307154 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Tue, 1 Oct 2019 11:03:13 +0300
Subject: [PATCH 01/16] ESPTREE

---
 README                                        |   1 +
 news.texi                                     |   7 +
 .../gogost/gost34112012256/esptree.go         |  60 ++++++
 .../gogost/gost34112012256/esptree_test.go    | 192 ++++++++++++++++++
 www.texi                                      |   1 +
 5 files changed, 261 insertions(+)
 create mode 100644 src/cypherpunks.ru/gogost/gost34112012256/esptree.go
 create mode 100644 src/cypherpunks.ru/gogost/gost34112012256/esptree_test.go

diff --git a/README b/README
index fa05b90..2f37487 100644
--- a/README
+++ b/README
@@ -20,6 +20,7 @@ GOST is GOvernment STandard of Russian Federation (and Soviet Union).
 * GOST R 34.13-2015 padding methods
 * MGM AEAD mode for 64 and 128 bit ciphers
 * TLSTREE keyscheduling function
+* ESPTREE keyscheduling function
 
 Known problems:
 
diff --git a/news.texi b/news.texi
index dc918f7..5569269 100644
--- a/news.texi
+++ b/news.texi
@@ -3,6 +3,13 @@
 
 @table @strong
 
+@anchor{Release 4.1}
+@item 4.1
+    @itemize
+    @item @code{ESPTREE} implementation
+
+    @end itemize
+
 @anchor{Release 4.0}
 @item 4.0
     @itemize
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/esptree.go b/src/cypherpunks.ru/gogost/gost34112012256/esptree.go
new file mode 100644
index 0000000..dceaeb7
--- /dev/null
+++ b/src/cypherpunks.ru/gogost/gost34112012256/esptree.go
@@ -0,0 +1,60 @@
+// 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 gost34112012256
+
+import (
+	"crypto/subtle"
+)
+
+type ESPTree struct {
+	keyRoot []byte
+	isPrev  [5]byte
+	key     []byte
+}
+
+func NewESPTree(keyRoot []byte) *ESPTree {
+	key := make([]byte, len(keyRoot))
+	copy(key, keyRoot)
+	t := &ESPTree{
+		keyRoot: key,
+		key:     make([]byte, Size),
+	}
+	t.isPrev[0] += 1 // invalidate cache
+	t.DeriveCached([]byte{0x00, 0x00, 0x00, 0x00, 0x00})
+	return t
+}
+
+func (t *ESPTree) DeriveCached(is []byte) ([]byte, bool) {
+	if len(is) != 1+2+2 {
+		panic("invalid i1+i2+i3 input")
+	}
+	if subtle.ConstantTimeCompare(t.isPrev[:], is) == 1 {
+		return t.key, true
+	}
+	kdf1 := NewKDF(t.keyRoot)
+	kdf2 := NewKDF(kdf1.Derive(t.key[:0], []byte("level1"), append([]byte{0}, is[0])))
+	kdf3 := NewKDF(kdf2.Derive(t.key[:0], []byte("level2"), is[1:3]))
+	kdf3.Derive(t.key[:0], []byte("level3"), is[3:5])
+	copy(t.isPrev[:], is)
+	return t.key, false
+}
+
+func (t *ESPTree) Derive(is []byte) []byte {
+	keyDerived := make([]byte, Size)
+	key, _ := t.DeriveCached(is)
+	copy(keyDerived, key)
+	return keyDerived
+}
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/esptree_test.go b/src/cypherpunks.ru/gogost/gost34112012256/esptree_test.go
new file mode 100644
index 0000000..a5c50e6
--- /dev/null
+++ b/src/cypherpunks.ru/gogost/gost34112012256/esptree_test.go
@@ -0,0 +1,192 @@
+// 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 gost34112012256
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestESPTree(t *testing.T) {
+	t.Run("1", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0xB6, 0x18, 0x0C, 0x14, 0x5C, 0x51, 0x2D, 0xBD,
+			0x69, 0xD9, 0xCE, 0xA9, 0x2C, 0xAC, 0x1B, 0x5C,
+			0xE1, 0xBC, 0xFA, 0x73, 0x79, 0x2D, 0x61, 0xAF,
+			0x0B, 0x44, 0x0D, 0x84, 0xB5, 0x22, 0xCC, 0x38,
+		})
+		is := []byte{0x00, 0x00, 0x00, 0x00, 0x00}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x2F, 0xF1, 0xC9, 0x0E, 0xDE, 0x78, 0x6E, 0x06,
+			0x1E, 0x17, 0xB3, 0x74, 0xD7, 0x82, 0xAF, 0x7B,
+			0xD8, 0x80, 0xBD, 0x52, 0x7C, 0x66, 0xA2, 0xBA,
+			0xDC, 0x3E, 0x56, 0x9A, 0xAB, 0x27, 0x1D, 0xA4,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("2", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0xB6, 0x18, 0x0C, 0x14, 0x5C, 0x51, 0x2D, 0xBD,
+			0x69, 0xD9, 0xCE, 0xA9, 0x2C, 0xAC, 0x1B, 0x5C,
+			0xE1, 0xBC, 0xFA, 0x73, 0x79, 0x2D, 0x61, 0xAF,
+			0x0B, 0x44, 0x0D, 0x84, 0xB5, 0x22, 0xCC, 0x38,
+		})
+		is := []byte{0x00, 0x00, 0x01, 0x00, 0x01}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x9A, 0xBA, 0xC6, 0x57, 0x78, 0x18, 0x0E, 0x6F,
+			0x2A, 0xF6, 0x1F, 0xB8, 0xD5, 0x71, 0x62, 0x36,
+			0x66, 0xC2, 0xF5, 0x13, 0x0D, 0x54, 0xE2, 0x11,
+			0x6C, 0x7D, 0x53, 0x0E, 0x6E, 0x7D, 0x48, 0xBC,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("3", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0x5B, 0x50, 0xBF, 0x33, 0x78, 0x87, 0x02, 0x38,
+			0xF3, 0xCA, 0x74, 0x0F, 0xD1, 0x24, 0xBA, 0x6C,
+			0x22, 0x83, 0xEF, 0x58, 0x9B, 0xE6, 0xF4, 0x6A,
+			0x89, 0x4A, 0xA3, 0x5D, 0x5F, 0x06, 0xB2, 0x03,
+		})
+		is := []byte{0x00, 0x00, 0x00, 0x00, 0x00}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x25, 0x65, 0x21, 0xE2, 0x70, 0xB7, 0x4A, 0x16,
+			0x4D, 0xFC, 0x26, 0xE6, 0xBF, 0x0C, 0xCA, 0x76,
+			0x5E, 0x9D, 0x41, 0x02, 0x7D, 0x4B, 0x7B, 0x19,
+			0x76, 0x2B, 0x1C, 0xC9, 0x01, 0xDC, 0xDE, 0x7F,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("4", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0x5B, 0x50, 0xBF, 0x33, 0x78, 0x87, 0x02, 0x38,
+			0xF3, 0xCA, 0x74, 0x0F, 0xD1, 0x24, 0xBA, 0x6C,
+			0x22, 0x83, 0xEF, 0x58, 0x9B, 0xE6, 0xF4, 0x6A,
+			0x89, 0x4A, 0xA3, 0x5D, 0x5F, 0x06, 0xB2, 0x03,
+		})
+		is := []byte{0x00, 0x00, 0x01, 0x00, 0x01}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x20, 0xE0, 0x46, 0xD4, 0x09, 0x83, 0x9B, 0x23,
+			0xF0, 0x66, 0xA5, 0x0A, 0x7A, 0x06, 0x5B, 0x4A,
+			0x39, 0x24, 0x4F, 0x0E, 0x29, 0xEF, 0x1E, 0x6F,
+			0x2E, 0x5D, 0x2E, 0x13, 0x55, 0xF5, 0xDA, 0x08,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("5", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0x98, 0xBD, 0x34, 0xCE, 0x3B, 0xE1, 0x9A, 0x34,
+			0x65, 0xE4, 0x87, 0xC0, 0x06, 0x48, 0x83, 0xF4,
+			0x88, 0xCC, 0x23, 0x92, 0x63, 0xDC, 0x32, 0x04,
+			0x91, 0x9B, 0x64, 0x3F, 0xE7, 0x57, 0xB2, 0xBE,
+		})
+		is := []byte{0x00, 0x00, 0x00, 0x00, 0x00}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x98, 0xF1, 0x03, 0x01, 0x81, 0x0A, 0x04, 0x1C,
+			0xDA, 0xDD, 0xE1, 0xBD, 0x85, 0xA0, 0x8F, 0x21,
+			0x8B, 0xAC, 0xB5, 0x7E, 0x00, 0x35, 0xE2, 0x22,
+			0xC8, 0x31, 0xE3, 0xE4, 0xF0, 0xA2, 0x0C, 0x8F,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("6", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0x98, 0xBD, 0x34, 0xCE, 0x3B, 0xE1, 0x9A, 0x34,
+			0x65, 0xE4, 0x87, 0xC0, 0x06, 0x48, 0x83, 0xF4,
+			0x88, 0xCC, 0x23, 0x92, 0x63, 0xDC, 0x32, 0x04,
+			0x91, 0x9B, 0x64, 0x3F, 0xE7, 0x57, 0xB2, 0xBE,
+		})
+		is := []byte{0x00, 0x00, 0x00, 0x00, 0x01}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x02, 0xC5, 0x41, 0x87, 0x7C, 0xC6, 0x23, 0xF3,
+			0xF1, 0x35, 0x91, 0x9A, 0x75, 0x13, 0xB6, 0xF8,
+			0xA8, 0xA1, 0x8C, 0xB2, 0x63, 0x99, 0x86, 0x2F,
+			0x50, 0x81, 0x4F, 0x52, 0x91, 0x01, 0x67, 0x84,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("7", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0xD0, 0x65, 0xB5, 0x30, 0xFA, 0x20, 0xB8, 0x24,
+			0xC7, 0x57, 0x0C, 0x1D, 0x86, 0x2A, 0xE3, 0x39,
+			0x2C, 0x1C, 0x07, 0x6D, 0xFA, 0xDA, 0x69, 0x75,
+			0x74, 0x4A, 0x07, 0xA8, 0x85, 0x7D, 0xBD, 0x30,
+		})
+		is := []byte{0x00, 0x00, 0x00, 0x00, 0x00}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0x4C, 0x61, 0x45, 0x99, 0xA0, 0xA0, 0x67, 0xF1,
+			0x94, 0x87, 0x24, 0x0A, 0xE1, 0x00, 0xE1, 0xB7,
+			0xEA, 0xF2, 0x3E, 0xDA, 0xF8, 0x7E, 0x38, 0x73,
+			0x50, 0x86, 0x1C, 0x68, 0x3B, 0xA4, 0x04, 0x46,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+	t.Run("8", func(t *testing.T) {
+		espTree := NewESPTree([]byte{
+			0xD0, 0x65, 0xB5, 0x30, 0xFA, 0x20, 0xB8, 0x24,
+			0xC7, 0x57, 0x0C, 0x1D, 0x86, 0x2A, 0xE3, 0x39,
+			0x2C, 0x1C, 0x07, 0x6D, 0xFA, 0xDA, 0x69, 0x75,
+			0x74, 0x4A, 0x07, 0xA8, 0x85, 0x7D, 0xBD, 0x30,
+		})
+		is := []byte{0x00, 0x00, 0x00, 0x00, 0x01}
+		got := espTree.Derive(is)
+		if bytes.Compare(got, []byte{
+			0xB4, 0xF3, 0xF9, 0x0D, 0xC4, 0x87, 0xFA, 0xB8,
+			0xC4, 0xAF, 0xD0, 0xEB, 0x45, 0x49, 0xF2, 0xF0,
+			0xE4, 0x36, 0x32, 0xB6, 0x79, 0x19, 0x37, 0x2E,
+			0x1E, 0x96, 0x09, 0xEA, 0xF0, 0xB8, 0xE2, 0x28,
+		}) != 0 {
+			t.FailNow()
+		}
+		if _, cached := espTree.DeriveCached(is); !cached {
+			t.FailNow()
+		}
+	})
+}
diff --git a/www.texi b/www.texi
index 61d3165..116cf20 100644
--- a/www.texi
+++ b/www.texi
@@ -50,6 +50,7 @@ Currently supported algorithms are:
 @item GOST R 34.13-2015 padding methods
 @item MGM AEAD mode for 64 and 128 bit ciphers
 @item TLSTREE keyscheduling function
+@item ESPTREE keyscheduling function
 @end itemize
 
 Please send questions, bug reports and patches to
-- 
2.44.0


From c07494bbd559b9d00f391e28cfd070e18afe9900 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Wed, 2 Oct 2019 17:20:57 +0300
Subject: [PATCH 02/16] go.cypherpunks.ru namespace usage

---
 {src/cypherpunks.ru/gogost/cmd => cmd}/streebog256/main.go   | 4 ++--
 {src/cypherpunks.ru/gogost/cmd => cmd}/streebog512/main.go   | 4 ++--
 go.mod                                                       | 5 +++++
 src/cypherpunks.ru/gogost/go.sum => go.sum                   | 4 ++--
 src/cypherpunks.ru/gogost/gogost.go => gogost.go             | 0
 .../gogost/gost28147 => gost28147}/cbc_test.go               | 0
 {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cfb.go    | 0
 .../gogost/gost28147 => gost28147}/cfb_test.go               | 0
 {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cipher.go | 0
 .../gogost/gost28147 => gost28147}/cipher_test.go            | 0
 {src/cypherpunks.ru/gogost/gost28147 => gost28147}/ctr.go    | 0
 .../gogost/gost28147 => gost28147}/ctr_test.go               | 0
 {src/cypherpunks.ru/gogost/gost28147 => gost28147}/ecb.go    | 0
 .../gogost/gost28147 => gost28147}/ecb_test.go               | 0
 {src/cypherpunks.ru/gogost/gost28147 => gost28147}/mac.go    | 0
 .../gogost/gost28147 => gost28147}/mac_test.go               | 0
 {src/cypherpunks.ru/gogost/gost28147 => gost28147}/sbox.go   | 0
 .../cypherpunks.ru/gogost/gost3410 => gost3410}/2001_test.go | 0
 .../cypherpunks.ru/gogost/gost3410 => gost3410}/2012_test.go | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/curve.go    | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/doc.go      | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/edwards.go  | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/params.go   | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/private.go  | 0
 .../gogost/gost3410 => gost3410}/private_test.go             | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/public.go   | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/ukm.go      | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/utils.go    | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko.go      | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko2001.go  | 4 ++--
 .../gogost/gost3410 => gost3410}/vko2001_test.go             | 0
 {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko2012.go  | 4 ++--
 .../gogost/gost3410 => gost3410}/vko2012_test.go             | 0
 .../gogost/gost34112012256 => gost34112012256}/esptree.go    | 0
 .../gost34112012256 => gost34112012256}/esptree_test.go      | 0
 .../gogost/gost34112012256 => gost34112012256}/hash.go       | 2 +-
 .../gogost/gost34112012256 => gost34112012256}/hkdf_test.go  | 0
 .../gogost/gost34112012256 => gost34112012256}/kdf.go        | 0
 .../gogost/gost34112012256 => gost34112012256}/kdf_test.go   | 0
 .../gogost/gost34112012256 => gost34112012256}/tlstree.go    | 0
 .../gost34112012256 => gost34112012256}/tlstree_test.go      | 0
 .../gogost/gost34112012512 => gost34112012512}/hash.go       | 2 +-
 {src/cypherpunks.ru/gogost/gost341194 => gost341194}/hash.go | 2 +-
 .../gogost/gost341194 => gost341194}/hash_test.go            | 2 +-
 .../gogost/gost341194 => gost341194}/pbkdf2_test.go          | 2 +-
 .../gogost/gost3412128 => gost3412128}/cipher.go             | 0
 .../gogost/gost3412128 => gost3412128}/cipher_test.go        | 0
 .../gogost/gost341264 => gost341264}/cipher.go               | 2 +-
 .../gogost/gost341264 => gost341264}/cipher_test.go          | 0
 {src/cypherpunks.ru/gogost/gost3413 => gost3413}/padding.go  | 0
 .../gogost/internal => internal}/gost34112012/hash.go        | 0
 .../gogost/internal => internal}/gost34112012/hash_test.go   | 0
 .../gogost/internal => internal}/gost34112012/hmac_test.go   | 0
 {src/cypherpunks.ru/gogost/mgm => mgm}/mode.go               | 0
 {src/cypherpunks.ru/gogost/mgm => mgm}/mode_test.go          | 4 ++--
 {src/cypherpunks.ru/gogost/mgm => mgm}/mul.go                | 0
 {src/cypherpunks.ru/gogost/mgm => mgm}/mul_test.go           | 4 ++--
 {src/cypherpunks.ru/gogost/mgm => mgm}/slice.go              | 0
 src/cypherpunks.ru/gogost/go.mod                             | 5 -----
 59 files changed, 25 insertions(+), 25 deletions(-)
 rename {src/cypherpunks.ru/gogost/cmd => cmd}/streebog256/main.go (93%)
 rename {src/cypherpunks.ru/gogost/cmd => cmd}/streebog512/main.go (93%)
 create mode 100644 go.mod
 rename src/cypherpunks.ru/gogost/go.sum => go.sum (76%)
 rename src/cypherpunks.ru/gogost/gogost.go => gogost.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cbc_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cfb.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cfb_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cipher.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/cipher_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/ctr.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/ctr_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/ecb.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/ecb_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/mac.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/mac_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost28147 => gost28147}/sbox.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/2001_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/2012_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/curve.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/doc.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/edwards.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/params.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/private.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/private_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/public.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/ukm.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/utils.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko2001.go (93%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko2001_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko2012.go (93%)
 rename {src/cypherpunks.ru/gogost/gost3410 => gost3410}/vko2012_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/esptree.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/esptree_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/hash.go (95%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/hkdf_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/kdf.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/kdf_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/tlstree.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012256 => gost34112012256}/tlstree_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost34112012512 => gost34112012512}/hash.go (95%)
 rename {src/cypherpunks.ru/gogost/gost341194 => gost341194}/hash.go (99%)
 rename {src/cypherpunks.ru/gogost/gost341194 => gost341194}/hash_test.go (99%)
 rename {src/cypherpunks.ru/gogost/gost341194 => gost341194}/pbkdf2_test.go (98%)
 rename {src/cypherpunks.ru/gogost/gost3412128 => gost3412128}/cipher.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3412128 => gost3412128}/cipher_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost341264 => gost341264}/cipher.go (98%)
 rename {src/cypherpunks.ru/gogost/gost341264 => gost341264}/cipher_test.go (100%)
 rename {src/cypherpunks.ru/gogost/gost3413 => gost3413}/padding.go (100%)
 rename {src/cypherpunks.ru/gogost/internal => internal}/gost34112012/hash.go (100%)
 rename {src/cypherpunks.ru/gogost/internal => internal}/gost34112012/hash_test.go (100%)
 rename {src/cypherpunks.ru/gogost/internal => internal}/gost34112012/hmac_test.go (100%)
 rename {src/cypherpunks.ru/gogost/mgm => mgm}/mode.go (100%)
 rename {src/cypherpunks.ru/gogost/mgm => mgm}/mode_test.go (98%)
 rename {src/cypherpunks.ru/gogost/mgm => mgm}/mul.go (100%)
 rename {src/cypherpunks.ru/gogost/mgm => mgm}/mul_test.go (94%)
 rename {src/cypherpunks.ru/gogost/mgm => mgm}/slice.go (100%)
 delete mode 100644 src/cypherpunks.ru/gogost/go.mod

diff --git a/src/cypherpunks.ru/gogost/cmd/streebog256/main.go b/cmd/streebog256/main.go
similarity index 93%
rename from src/cypherpunks.ru/gogost/cmd/streebog256/main.go
rename to cmd/streebog256/main.go
index 55d1914..9722168 100644
--- a/src/cypherpunks.ru/gogost/cmd/streebog256/main.go
+++ b/cmd/streebog256/main.go
@@ -23,8 +23,8 @@ import (
 	"io"
 	"os"
 
-	"cypherpunks.ru/gogost"
-	"cypherpunks.ru/gogost/gost34112012256"
+	"go.cypherpunks.ru/gogost/v4"
+	"go.cypherpunks.ru/gogost/v4/gost34112012256"
 )
 
 var (
diff --git a/src/cypherpunks.ru/gogost/cmd/streebog512/main.go b/cmd/streebog512/main.go
similarity index 93%
rename from src/cypherpunks.ru/gogost/cmd/streebog512/main.go
rename to cmd/streebog512/main.go
index 24afe90..41d0c6a 100644
--- a/src/cypherpunks.ru/gogost/cmd/streebog512/main.go
+++ b/cmd/streebog512/main.go
@@ -23,8 +23,8 @@ import (
 	"io"
 	"os"
 
-	"cypherpunks.ru/gogost"
-	"cypherpunks.ru/gogost/gost34112012512"
+	"go.cypherpunks.ru/gogost/v4"
+	"go.cypherpunks.ru/gogost/v4/gost34112012512"
 )
 
 var (
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..21dce95
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,5 @@
+module go.cypherpunks.ru/gogost/v4
+
+go 1.12
+
+require golang.org/x/crypto v0.0.0-20191001170739-f9e2070545dc
diff --git a/src/cypherpunks.ru/gogost/go.sum b/go.sum
similarity index 76%
rename from src/cypherpunks.ru/gogost/go.sum
rename to go.sum
index b75b87f..a95cc32 100644
--- a/src/cypherpunks.ru/gogost/go.sum
+++ b/go.sum
@@ -1,6 +1,6 @@
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4 h1:HuIa8hRrWRSrqYzx1qI49NNxhdi2PrY7gxVSq1JjLDc=
-golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/crypto v0.0.0-20191001170739-f9e2070545dc h1:KyTYo8xkh/2WdbFLUyQwBS0Jfn3qfZ9QmuPbok2oENE=
+golang.org/x/crypto v0.0.0-20191001170739-f9e2070545dc/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
 golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
diff --git a/src/cypherpunks.ru/gogost/gogost.go b/gogost.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gogost.go
rename to gogost.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/cbc_test.go b/gost28147/cbc_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/cbc_test.go
rename to gost28147/cbc_test.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/cfb.go b/gost28147/cfb.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/cfb.go
rename to gost28147/cfb.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/cfb_test.go b/gost28147/cfb_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/cfb_test.go
rename to gost28147/cfb_test.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/cipher.go b/gost28147/cipher.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/cipher.go
rename to gost28147/cipher.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/cipher_test.go b/gost28147/cipher_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/cipher_test.go
rename to gost28147/cipher_test.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/ctr.go b/gost28147/ctr.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/ctr.go
rename to gost28147/ctr.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/ctr_test.go b/gost28147/ctr_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/ctr_test.go
rename to gost28147/ctr_test.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/ecb.go b/gost28147/ecb.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/ecb.go
rename to gost28147/ecb.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/ecb_test.go b/gost28147/ecb_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/ecb_test.go
rename to gost28147/ecb_test.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/mac.go b/gost28147/mac.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/mac.go
rename to gost28147/mac.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/mac_test.go b/gost28147/mac_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/mac_test.go
rename to gost28147/mac_test.go
diff --git a/src/cypherpunks.ru/gogost/gost28147/sbox.go b/gost28147/sbox.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost28147/sbox.go
rename to gost28147/sbox.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/2001_test.go b/gost3410/2001_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/2001_test.go
rename to gost3410/2001_test.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/2012_test.go b/gost3410/2012_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/2012_test.go
rename to gost3410/2012_test.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/curve.go b/gost3410/curve.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/curve.go
rename to gost3410/curve.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/doc.go b/gost3410/doc.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/doc.go
rename to gost3410/doc.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/edwards.go b/gost3410/edwards.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/edwards.go
rename to gost3410/edwards.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/params.go b/gost3410/params.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/params.go
rename to gost3410/params.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/private.go b/gost3410/private.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/private.go
rename to gost3410/private.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/private_test.go b/gost3410/private_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/private_test.go
rename to gost3410/private_test.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/public.go b/gost3410/public.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/public.go
rename to gost3410/public.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/ukm.go b/gost3410/ukm.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/ukm.go
rename to gost3410/ukm.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/utils.go b/gost3410/utils.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/utils.go
rename to gost3410/utils.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/vko.go b/gost3410/vko.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/vko.go
rename to gost3410/vko.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/vko2001.go b/gost3410/vko2001.go
similarity index 93%
rename from src/cypherpunks.ru/gogost/gost3410/vko2001.go
rename to gost3410/vko2001.go
index 18fff3e..ed49d8f 100644
--- a/src/cypherpunks.ru/gogost/gost3410/vko2001.go
+++ b/gost3410/vko2001.go
@@ -19,8 +19,8 @@ import (
 	"errors"
 	"math/big"
 
-	"cypherpunks.ru/gogost/gost28147"
-	"cypherpunks.ru/gogost/gost341194"
+	"go.cypherpunks.ru/gogost/v4/gost28147"
+	"go.cypherpunks.ru/gogost/v4/gost341194"
 )
 
 // RFC 4357 VKO GOST R 34.10-2001 key agreement function.
diff --git a/src/cypherpunks.ru/gogost/gost3410/vko2001_test.go b/gost3410/vko2001_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/vko2001_test.go
rename to gost3410/vko2001_test.go
diff --git a/src/cypherpunks.ru/gogost/gost3410/vko2012.go b/gost3410/vko2012.go
similarity index 93%
rename from src/cypherpunks.ru/gogost/gost3410/vko2012.go
rename to gost3410/vko2012.go
index 836d3a4..7a30b4e 100644
--- a/src/cypherpunks.ru/gogost/gost3410/vko2012.go
+++ b/gost3410/vko2012.go
@@ -18,8 +18,8 @@ package gost3410
 import (
 	"math/big"
 
-	"cypherpunks.ru/gogost/gost34112012256"
-	"cypherpunks.ru/gogost/gost34112012512"
+	"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.
diff --git a/src/cypherpunks.ru/gogost/gost3410/vko2012_test.go b/gost3410/vko2012_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3410/vko2012_test.go
rename to gost3410/vko2012_test.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/esptree.go b/gost34112012256/esptree.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/esptree.go
rename to gost34112012256/esptree.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/esptree_test.go b/gost34112012256/esptree_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/esptree_test.go
rename to gost34112012256/esptree_test.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/hash.go b/gost34112012256/hash.go
similarity index 95%
rename from src/cypherpunks.ru/gogost/gost34112012256/hash.go
rename to gost34112012256/hash.go
index 30e308b..f1f7e9b 100644
--- a/src/cypherpunks.ru/gogost/gost34112012256/hash.go
+++ b/gost34112012256/hash.go
@@ -20,7 +20,7 @@ package gost34112012256
 import (
 	"hash"
 
-	"cypherpunks.ru/gogost/internal/gost34112012"
+	"go.cypherpunks.ru/gogost/v4/internal/gost34112012"
 )
 
 const (
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/hkdf_test.go b/gost34112012256/hkdf_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/hkdf_test.go
rename to gost34112012256/hkdf_test.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/kdf.go b/gost34112012256/kdf.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/kdf.go
rename to gost34112012256/kdf.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/kdf_test.go b/gost34112012256/kdf_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/kdf_test.go
rename to gost34112012256/kdf_test.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/tlstree.go b/gost34112012256/tlstree.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/tlstree.go
rename to gost34112012256/tlstree.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012256/tlstree_test.go b/gost34112012256/tlstree_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost34112012256/tlstree_test.go
rename to gost34112012256/tlstree_test.go
diff --git a/src/cypherpunks.ru/gogost/gost34112012512/hash.go b/gost34112012512/hash.go
similarity index 95%
rename from src/cypherpunks.ru/gogost/gost34112012512/hash.go
rename to gost34112012512/hash.go
index bdfd538..06e1a86 100644
--- a/src/cypherpunks.ru/gogost/gost34112012512/hash.go
+++ b/gost34112012512/hash.go
@@ -20,7 +20,7 @@ package gost34112012512
 import (
 	"hash"
 
-	"cypherpunks.ru/gogost/internal/gost34112012"
+	"go.cypherpunks.ru/gogost/v4/internal/gost34112012"
 )
 
 const (
diff --git a/src/cypherpunks.ru/gogost/gost341194/hash.go b/gost341194/hash.go
similarity index 99%
rename from src/cypherpunks.ru/gogost/gost341194/hash.go
rename to gost341194/hash.go
index 61d506c..e386ddd 100644
--- a/src/cypherpunks.ru/gogost/gost341194/hash.go
+++ b/gost341194/hash.go
@@ -21,7 +21,7 @@ import (
 	"encoding/binary"
 	"math/big"
 
-	"cypherpunks.ru/gogost/gost28147"
+	"go.cypherpunks.ru/gogost/v4/gost28147"
 )
 
 const (
diff --git a/src/cypherpunks.ru/gogost/gost341194/hash_test.go b/gost341194/hash_test.go
similarity index 99%
rename from src/cypherpunks.ru/gogost/gost341194/hash_test.go
rename to gost341194/hash_test.go
index bcd86c5..de5d988 100644
--- a/src/cypherpunks.ru/gogost/gost341194/hash_test.go
+++ b/gost341194/hash_test.go
@@ -22,7 +22,7 @@ import (
 	"testing"
 	"testing/quick"
 
-	"cypherpunks.ru/gogost/gost28147"
+	"go.cypherpunks.ru/gogost/v4/gost28147"
 )
 
 func TestHashInterface(t *testing.T) {
diff --git a/src/cypherpunks.ru/gogost/gost341194/pbkdf2_test.go b/gost341194/pbkdf2_test.go
similarity index 98%
rename from src/cypherpunks.ru/gogost/gost341194/pbkdf2_test.go
rename to gost341194/pbkdf2_test.go
index 86ecea8..20c5c13 100644
--- a/src/cypherpunks.ru/gogost/gost341194/pbkdf2_test.go
+++ b/gost341194/pbkdf2_test.go
@@ -20,7 +20,7 @@ import (
 	"hash"
 	"testing"
 
-	"cypherpunks.ru/gogost/gost28147"
+	"go.cypherpunks.ru/gogost/v4/gost28147"
 	"golang.org/x/crypto/pbkdf2"
 )
 
diff --git a/src/cypherpunks.ru/gogost/gost3412128/cipher.go b/gost3412128/cipher.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3412128/cipher.go
rename to gost3412128/cipher.go
diff --git a/src/cypherpunks.ru/gogost/gost3412128/cipher_test.go b/gost3412128/cipher_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3412128/cipher_test.go
rename to gost3412128/cipher_test.go
diff --git a/src/cypherpunks.ru/gogost/gost341264/cipher.go b/gost341264/cipher.go
similarity index 98%
rename from src/cypherpunks.ru/gogost/gost341264/cipher.go
rename to gost341264/cipher.go
index 53a2792..f308080 100644
--- a/src/cypherpunks.ru/gogost/gost341264/cipher.go
+++ b/gost341264/cipher.go
@@ -17,7 +17,7 @@
 package gost341264
 
 import (
-	"cypherpunks.ru/gogost/gost28147"
+	"go.cypherpunks.ru/gogost/v4/gost28147"
 )
 
 const (
diff --git a/src/cypherpunks.ru/gogost/gost341264/cipher_test.go b/gost341264/cipher_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost341264/cipher_test.go
rename to gost341264/cipher_test.go
diff --git a/src/cypherpunks.ru/gogost/gost3413/padding.go b/gost3413/padding.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/gost3413/padding.go
rename to gost3413/padding.go
diff --git a/src/cypherpunks.ru/gogost/internal/gost34112012/hash.go b/internal/gost34112012/hash.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/internal/gost34112012/hash.go
rename to internal/gost34112012/hash.go
diff --git a/src/cypherpunks.ru/gogost/internal/gost34112012/hash_test.go b/internal/gost34112012/hash_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/internal/gost34112012/hash_test.go
rename to internal/gost34112012/hash_test.go
diff --git a/src/cypherpunks.ru/gogost/internal/gost34112012/hmac_test.go b/internal/gost34112012/hmac_test.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/internal/gost34112012/hmac_test.go
rename to internal/gost34112012/hmac_test.go
diff --git a/src/cypherpunks.ru/gogost/mgm/mode.go b/mgm/mode.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/mgm/mode.go
rename to mgm/mode.go
diff --git a/src/cypherpunks.ru/gogost/mgm/mode_test.go b/mgm/mode_test.go
similarity index 98%
rename from src/cypherpunks.ru/gogost/mgm/mode_test.go
rename to mgm/mode_test.go
index aedd59b..38d6ee9 100644
--- a/src/cypherpunks.ru/gogost/mgm/mode_test.go
+++ b/mgm/mode_test.go
@@ -22,8 +22,8 @@ import (
 	"testing"
 	"testing/quick"
 
-	"cypherpunks.ru/gogost/gost3412128"
-	"cypherpunks.ru/gogost/gost341264"
+	"go.cypherpunks.ru/gogost/v4/gost3412128"
+	"go.cypherpunks.ru/gogost/v4/gost341264"
 )
 
 func TestVector(t *testing.T) {
diff --git a/src/cypherpunks.ru/gogost/mgm/mul.go b/mgm/mul.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/mgm/mul.go
rename to mgm/mul.go
diff --git a/src/cypherpunks.ru/gogost/mgm/mul_test.go b/mgm/mul_test.go
similarity index 94%
rename from src/cypherpunks.ru/gogost/mgm/mul_test.go
rename to mgm/mul_test.go
index 7420859..9a08946 100644
--- a/src/cypherpunks.ru/gogost/mgm/mul_test.go
+++ b/mgm/mul_test.go
@@ -20,8 +20,8 @@ import (
 	"math/big"
 	"testing"
 
-	"cypherpunks.ru/gogost/gost3412128"
-	"cypherpunks.ru/gogost/gost341264"
+	"go.cypherpunks.ru/gogost/v4/gost3412128"
+	"go.cypherpunks.ru/gogost/v4/gost341264"
 )
 
 func BenchmarkMul64(b *testing.B) {
diff --git a/src/cypherpunks.ru/gogost/mgm/slice.go b/mgm/slice.go
similarity index 100%
rename from src/cypherpunks.ru/gogost/mgm/slice.go
rename to mgm/slice.go
diff --git a/src/cypherpunks.ru/gogost/go.mod b/src/cypherpunks.ru/gogost/go.mod
deleted file mode 100644
index 2876534..0000000
--- a/src/cypherpunks.ru/gogost/go.mod
+++ /dev/null
@@ -1,5 +0,0 @@
-module cypherpunks.ru/gogost
-
-go 1.12
-
-require golang.org/x/crypto v0.0.0-20190701094942-4def268fd1a4
-- 
2.44.0


From 30588af8972ef366e0eb9a3e5aac799946de0e1a Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 11:11:55 +0300
Subject: [PATCH 03/16] Prepare for release

---
 .gitmodules   |  0
 INSTALL       | 34 +++++++++++++++++++---------------
 NEWS          |  8 ++++++++
 VERSION       |  2 +-
 common.mk     |  9 +++++----
 download.texi | 36 +++++++++++++++++++++---------------
 makedist.sh   | 24 +++++++++++++++++++-----
 news.texi     |  6 ++++++
 8 files changed, 79 insertions(+), 40 deletions(-)
 delete mode 100644 .gitmodules

diff --git a/.gitmodules b/.gitmodules
deleted file mode 100644
index e69de29..0000000
diff --git a/INSTALL b/INSTALL
index fedfbac..bf0b19c 100644
--- a/INSTALL
+++ b/INSTALL
@@ -1,28 +1,29 @@
 Preferable way is to download tarball with the signature from official
 website and, for example, run tests with benchmarks:
 
-    % wget http://gogost.cypherpunks.ru/gogost-1.1.tar.xz
-    % wget http://gogost.cypherpunks.ru/gogost-1.1.tar.xz.sig
-    % gpg --verify gogost-1.1.tar.xz.sig gogost-1.1.tar.xz
-    % xz -d < gogost-1.1.tar.xz | tar xf -
-    % make -C gogost-1.1 all bench
-    % echo hello world | ./gogost-1.1/streebog256
+    $ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz
+    $ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz.sig
+    $ gpg --verify gogost-4.1.0.tar.xz.sig gogost-4.1.0.tar.xz
+    $ xz -d < gogost-4.1.0.tar.xz | tar xf -
+    $ make -C gogost-4.1.0 all bench
+    $ echo hello world | ./gogost-4.1.0/streebog256
     f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 
 And then you can include its source code in your project for example
 like this:
 
-    % mkdir -p myproj/src
-    % export GOPATH=$PWD/myproj
-    % cd myproj/src
-    % cat > main.go <<EOF
+    $ mkdir -p myproj/src
+    $ cp -r gogost-4.1.0/src/go.cypherpunks.ru myproj/src
+    $ export GOPATH=$PWD/myproj
+    $ cd myproj/src
+    $ cat > main.go <<EOF
     package main
 
     import (
         "encoding/hex"
         "fmt"
 
-        "cypherpunks.ru/gogost/gost34112012256"
+        "go.cypherpunks.ru/gogost/v4/gost34112012256"
     )
 
     func main() {
@@ -31,10 +32,13 @@ like this:
         fmt.Println(hex.EncodeToString(h.Sum(nil)))
     }
     EOF
-    % cp -r ../../gogost-1.1/src/cypherpunks.ru .
-    % go run main.go
+    $ go run main.go
     c600fd9dd049cf8abd2f5b32e840d2cb0e41ea44de1c155dcd88dc84fe58a855
 
+GoGOST is also go-get-able. For example to use streebog256 utility:
+
+    $ go get go.cypherpunks.ru/gogost/cmd/streebog256
+
 You have to verify downloaded tarballs integrity and authenticity to be
 sure that you retrieved trusted and untampered software. GNU Privacy
 Guard is used for that purpose.
@@ -48,5 +52,5 @@ resources.
     uid   GoGOST releases <gogost at cypherpunks dot ru>
 
     Look in PUBKEY.asc file.
-    % gpg --auto-key-locate dane --locate-keys gogost at cypherpunks dot ru
-    % gpg --auto-key-locate wkd --locate-keys gogost at cypherpunks dot ru
+    $ gpg --auto-key-locate dane --locate-keys gogost at cypherpunks dot ru
+    $ gpg --auto-key-locate wkd --locate-keys gogost at cypherpunks dot ru
diff --git a/NEWS b/NEWS
index 9b82e8c..452e15a 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,11 @@
+4.1:
+    * ESPTREE implementation
+    * CurveIdtc26gost34102012256paramSetB, CurveIdtc26gost34102012256paramSetC,
+      CurveIdtc26gost34102012256paramSetD curve aliases
+    * Forbid any later GNU GPL version autousage
+      (project's licence now is GNU GPLv3 only)
+    * Project now is go-get-able: go get go.cypherpunks.ru/gogost/v4
+
 4.0:
     * Backward incompatible change: all keys passing to encryption
       functions are slices now, not the fixed arrays. That heavily
diff --git a/VERSION b/VERSION
index 5186d07..7d5c902 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.0
+4.1
diff --git a/common.mk b/common.mk
index e528f9a..c4bb97d 100644
--- a/common.mk
+++ b/common.mk
@@ -1,12 +1,13 @@
-LDFLAGS = -X cypherpunks.ru/gogost.Version=$(VERSION)
+MOD = go.cypherpunks.ru/gogost/v4
+LDFLAGS = -X $(MOD).Version=$(VERSION)
 
 all: streebog256 streebog512
 
 streebog256:
-	GOPATH=$(GOPATH) go build -ldflags "$(LDFLAGS)" cypherpunks.ru/gogost/cmd/streebog256
+	GOPATH=$(GOPATH) go build -ldflags "$(LDFLAGS)" $(MOD)/cmd/streebog256
 
 streebog512:
-	GOPATH=$(GOPATH) go build -ldflags "$(LDFLAGS)" cypherpunks.ru/gogost/cmd/streebog512
+	GOPATH=$(GOPATH) go build -ldflags "$(LDFLAGS)" $(MOD)/cmd/streebog512
 
 bench:
-	GOPATH=$(GOPATH) go test -benchmem -bench . cypherpunks.ru/gogost/...
+	GOPATH=$(GOPATH) go test -benchmem -bench . $(MOD)/...
diff --git a/download.texi b/download.texi
index e506a2a..390d3cc 100644
--- a/download.texi
+++ b/download.texi
@@ -5,12 +5,12 @@ Preferable way is to download tarball with the signature from
 website and, for example, run tests with benchmarks:
 
 @verbatim
-% wget http://gogost.cypherpunks.ru/gogost-4.0.tar.xz
-% wget http://gogost.cypherpunks.ru/gogost-4.0.tar.xz.sig
-% gpg --verify gogost-4.0.tar.xz.sig gogost-4.0.tar.xz
-% xz -d < gogost-4.0.tar.xz | tar xf -
-% make -C gogost-4.0 all bench
-% echo hello world | ./gogost-4.0/streebog256
+$ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz
+$ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz.sig
+$ gpg --verify gogost-4.1.0.tar.xz.sig gogost-4.1.0.tar.xz
+$ xz -d < gogost-4.1.0.tar.xz | tar xf -
+$ make -C gogost-4.1.0 all bench
+$ echo hello world | ./gogost-4.1.0/streebog256
 f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 @end verbatim
 
@@ -18,17 +18,18 @@ And then you can include its source code in your project for example
 like this:
 
 @verbatim
-% mkdir -p myproj/src
-% export GOPATH=$PWD/myproj
-% cd myproj/src
-% cat > main.go <<EOF
+$ mkdir -p myproj/src
+$ cp -r gogost-4.1.0/src/go.cypherpunks.ru myproj/src
+$ export GOPATH=$PWD/myproj
+$ cd myproj/src
+$ cat > main.go <<EOF
 package main
 
 import (
     "encoding/hex"
     "fmt"
 
-    "cypherpunks.ru/gogost/gost34112012256"
+    "go.cypherpunks.ru/gogost/v4/gost34112012256"
 )
 
 func main() {
@@ -37,11 +38,16 @@ func main() {
     fmt.Println(hex.EncodeToString(h.Sum(nil)))
 }
 EOF
-% cp -r ../../gogost-4.0/src/cypherpunks.ru .
-% go run main.go
+$ go run main.go
 c600fd9dd049cf8abd2f5b32e840d2cb0e41ea44de1c155dcd88dc84fe58a855
 @end verbatim
 
+GoGOST is also @command{go get}-able. For example to use
+@command{streebog256} utility:
+@verbatim
+$ go get go.cypherpunks.ru/gogost/cmd/streebog256
+@end verbatim
+
 @multitable {XXXXX} {XXXX-XX-XX} {XXXX KiB} {link sign} {xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx} {xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
 @headitem Version @tab Date @tab Size @tab Tarball @tab SHA256 checksum @tab Streebog-256 checksum
 
@@ -93,8 +99,8 @@ uid   GoGOST releases <gogost at cypherpunks dot ru>
 
 @item
 @verbatim
-% gpg --auto-key-locate dane --locate-keys gogost at cypherpunks dot ru
-% gpg --auto-key-locate wkd --locate-keys gogost at cypherpunks dot ru
+$ gpg --auto-key-locate dane --locate-keys gogost at cypherpunks dot ru
+$ gpg --auto-key-locate wkd --locate-keys gogost at cypherpunks dot ru
 @end verbatim
 
 @item
diff --git a/makedist.sh b/makedist.sh
index 6c79acc..2fbbc35 100755
--- a/makedist.sh
+++ b/makedist.sh
@@ -9,14 +9,28 @@ git clone . $tmp/gogost-$release
 cd $tmp/gogost-$release
 git checkout $release
 
-crypto_path=src/cypherpunks.ru/gogost/vendor/golang.org/x/crypto
-mkdir -p $crypto_path
-( cd $cur/gopath/pkg/mod/golang.org/x/crypto@v0.0.0-20190701094942-4def268fd1a4 ; \
+mod_name=$(sed -n 's/^module //p' go.mod)
+crypto_mod_path=$(sed -n 's#^require \(golang.org/x/crypto\) \(.*\)$#\1@\2#p' go.mod)
+mkdir -p src/$mod_name
+mv \
+    gost28147 \
+    gost3410 \
+    gost34112012256 \
+    gost34112012512 \
+    gost341194 \
+    gost3412128 \
+    gost341264 \
+    gost3413 \
+    mgm \
+    internal gogost.go go.mod go.sum src/$mod_name
+
+mkdir -p src/golang.org/x/crypto
+( cd $GOPATH/pkg/mod/$crypto_mod_path ; \
     tar cf - AUTHORS CONTRIBUTORS LICENSE PATENTS README.md pbkdf2 hkdf ) |
-    tar xfC - $crypto_path
+    tar xfC - src/golang.org/x/crypto
 
 find . -name .git -type d | xargs rm -fr
-rm -f www* makedist* TODO
+rm -f www* news.texi style.css makedist* TODO
 
 find . -type d -exec chmod 700 {} \;
 find . -type f -exec chmod 600 {} \;
diff --git a/news.texi b/news.texi
index 5569269..91449e2 100644
--- a/news.texi
+++ b/news.texi
@@ -7,6 +7,12 @@
 @item 4.1
     @itemize
     @item @code{ESPTREE} implementation
+    @item @code{CurveIdtc26gost34102012256paramSetB},
+        @code{CurveIdtc26gost34102012256paramSetC},
+        @code{CurveIdtc26gost34102012256paramSetD} curve aliases
+    @item Forbid any later GNU GPL version autousage
+        (project's licence now is GNU GPLv3 only)
+    @item Project now is go-get-able: @command{go get go.cypherpunks.ru/gogost/v4}
 
     @end itemize
 
-- 
2.44.0


From 124a11069e1ed7b617a740341d90d6a269bdd41b Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 13:56:30 +0300
Subject: [PATCH 04/16] Work with v-prefixed versions

---
 makedist.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/makedist.sh b/makedist.sh
index 2fbbc35..18ccc41 100755
--- a/makedist.sh
+++ b/makedist.sh
@@ -7,7 +7,7 @@ release=$1
 
 git clone . $tmp/gogost-$release
 cd $tmp/gogost-$release
-git checkout $release
+git checkout v$release
 
 mod_name=$(sed -n 's/^module //p' go.mod)
 crypto_mod_path=$(sed -n 's#^require \(golang.org/x/crypto\) \(.*\)$#\1@\2#p' go.mod)
-- 
2.44.0


From 9c077144213d28d7cdfa2d4383b0a3677458a2ea Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 13:58:03 +0300
Subject: [PATCH 05/16] Include cmd in source code tree

---
 makedist.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/makedist.sh b/makedist.sh
index 18ccc41..5aa690f 100755
--- a/makedist.sh
+++ b/makedist.sh
@@ -22,7 +22,7 @@ mv \
     gost341264 \
     gost3413 \
     mgm \
-    internal gogost.go go.mod go.sum src/$mod_name
+    cmd internal gogost.go go.mod go.sum src/$mod_name
 
 mkdir -p src/golang.org/x/crypto
 ( cd $GOPATH/pkg/mod/$crypto_mod_path ; \
-- 
2.44.0


From 208ade9f5eec08a8903b9c224449f3e5e652b1a2 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 15:05:04 +0300
Subject: [PATCH 06/16] No website related files in tarball

---
 makedist.sh | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/makedist.sh b/makedist.sh
index 5aa690f..7ed9a15 100755
--- a/makedist.sh
+++ b/makedist.sh
@@ -30,7 +30,7 @@ mkdir -p src/golang.org/x/crypto
     tar xfC - src/golang.org/x/crypto
 
 find . -name .git -type d | xargs rm -fr
-rm -f www* news.texi style.css makedist* TODO
+rm -f *.texi www.mk style.css makedist* TODO
 
 find . -type d -exec chmod 700 {} \;
 find . -type f -exec chmod 600 {} \;
-- 
2.44.0


From ff7db92b63036f4a13b35a29808f7a2c84d51bd7 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 14:00:04 +0300
Subject: [PATCH 07/16] Download link for 4.1.0 release

---
 download.texi | 5 +++++
 news.texi     | 8 ++++----
 2 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/download.texi b/download.texi
index 390d3cc..cacd24b 100644
--- a/download.texi
+++ b/download.texi
@@ -51,6 +51,11 @@ $ go get go.cypherpunks.ru/gogost/cmd/streebog256
 @multitable {XXXXX} {XXXX-XX-XX} {XXXX KiB} {link sign} {xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx} {xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
 @headitem Version @tab Date @tab Size @tab Tarball @tab SHA256 checksum @tab Streebog-256 checksum
 
+@item @ref{Release 4.1.0, 4.1.0} @tab 2019-10-03 @tab 55 KiB
+@tab @url{gogost-4.1.0.tar.xz, link} @url{gogost-4.1.0.tar.xz.sig, sign}
+@tab @code{F2FEF2E0 ADEB5742 FA2B3338 64E8B91B 3CCAA97D 5BA62177 21E08A11 F1FA8133}
+@tab @code{72e0d52aa25158ab1bb45e5498ce703b516c616b71101b74d5ee259f516c4e91}
+
 @item @ref{Release 4.0, 4.0} @tab 2019-08-12 @tab 56 KiB
 @tab @url{gogost-4.0.tar.xz, link} @url{gogost-4.0.tar.xz.sig, sign}
 @tab @code{4899B930 2110C9A9 592821D6 B206146F 2A66FC5A 3DEE9D6E 11F5EA51 72FEE6E6}
diff --git a/news.texi b/news.texi
index 91449e2..8fde0ef 100644
--- a/news.texi
+++ b/news.texi
@@ -3,8 +3,8 @@
 
 @table @strong
 
-@anchor{Release 4.1}
-@item 4.1
+@anchor{Release 4.1.0}
+@item 4.1.0
     @itemize
     @item @code{ESPTREE} implementation
     @item @code{CurveIdtc26gost34102012256paramSetB},
@@ -12,8 +12,8 @@
         @code{CurveIdtc26gost34102012256paramSetD} curve aliases
     @item Forbid any later GNU GPL version autousage
         (project's licence now is GNU GPLv3 only)
-    @item Project now is go-get-able: @command{go get go.cypherpunks.ru/gogost/v4}
-
+    @item Project now is @command{go get}-able:
+        @command{go get go.cypherpunks.ru/gogost/v4}
     @end itemize
 
 @anchor{Release 4.0}
-- 
2.44.0


From 1510f0036d4f2df6af3e7004b0d252ca6a851544 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 15:16:35 +0300
Subject: [PATCH 08/16] Corrected go get command examples

---
 NEWS      | 6 ++++--
 news.texi | 6 ++++--
 2 files changed, 8 insertions(+), 4 deletions(-)

diff --git a/NEWS b/NEWS
index 452e15a..5b13d25 100644
--- a/NEWS
+++ b/NEWS
@@ -1,10 +1,12 @@
-4.1:
+4.1.0:
     * ESPTREE implementation
     * CurveIdtc26gost34102012256paramSetB, CurveIdtc26gost34102012256paramSetC,
       CurveIdtc26gost34102012256paramSetD curve aliases
     * Forbid any later GNU GPL version autousage
       (project's licence now is GNU GPLv3 only)
-    * Project now is go-get-able: go get go.cypherpunks.ru/gogost/v4
+    * Project now is go get-able and uses go.cypherpunks.ru namespace:
+      go get go.cypherpunks.ru/gogost
+      go get go.cypherpunks.ru/gogost/cmd/streebog{256,512}
 
 4.0:
     * Backward incompatible change: all keys passing to encryption
diff --git a/news.texi b/news.texi
index 8fde0ef..12acd2e 100644
--- a/news.texi
+++ b/news.texi
@@ -12,8 +12,10 @@
         @code{CurveIdtc26gost34102012256paramSetD} curve aliases
     @item Forbid any later GNU GPL version autousage
         (project's licence now is GNU GPLv3 only)
-    @item Project now is @command{go get}-able:
-        @command{go get go.cypherpunks.ru/gogost/v4}
+    @item Project now is @command{go get}-able and uses
+        @code{go.cypherpunks.ru} namespace:
+        @command{go get go.cypherpunks.ru/gogost},
+        @command{go get go.cypherpunks.ru/gogost/cmd/streebog@{256,512@}}.
     @end itemize
 
 @anchor{Release 4.0}
-- 
2.44.0


From 830040ac890e529af5f4b58574a6835d2b91e493 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Thu, 3 Oct 2019 15:36:53 +0300
Subject: [PATCH 09/16] Let "hello world" string be the same in every example

---
 INSTALL       | 4 ++--
 download.texi | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/INSTALL b/INSTALL
index bf0b19c..690ba98 100644
--- a/INSTALL
+++ b/INSTALL
@@ -28,12 +28,12 @@ like this:
 
     func main() {
         h := gost34112012256.New()
-        h.Write([]byte("hello world"))
+        h.Write([]byte("hello world\n"))
         fmt.Println(hex.EncodeToString(h.Sum(nil)))
     }
     EOF
     $ go run main.go
-    c600fd9dd049cf8abd2f5b32e840d2cb0e41ea44de1c155dcd88dc84fe58a855
+    f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 
 GoGOST is also go-get-able. For example to use streebog256 utility:
 
diff --git a/download.texi b/download.texi
index cacd24b..bfdc5bc 100644
--- a/download.texi
+++ b/download.texi
@@ -34,12 +34,12 @@ import (
 
 func main() {
     h := gost34112012256.New()
-    h.Write([]byte("hello world"))
+    h.Write([]byte("hello world\n"))
     fmt.Println(hex.EncodeToString(h.Sum(nil)))
 }
 EOF
 $ go run main.go
-c600fd9dd049cf8abd2f5b32e840d2cb0e41ea44de1c155dcd88dc84fe58a855
+f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 @end verbatim
 
 GoGOST is also @command{go get}-able. For example to use
-- 
2.44.0


From 0cd98b2e4b70e33a24d79a6ceea6b39b1016e0bf Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 4 Oct 2019 16:10:45 +0300
Subject: [PATCH 10/16] Use UNKNOWN version by default

---
 gogost.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/gogost.go b/gogost.go
index 767e461..de5246b 100644
--- a/gogost.go
+++ b/gogost.go
@@ -2,5 +2,5 @@
 package gogost
 
 var (
-	Version string
+	Version string = "UNKNOWN"
 )
-- 
2.44.0


From 1d33d2df82ec0580eedd7e9facb72c0e9096a37c Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 4 Oct 2019 16:11:05 +0300
Subject: [PATCH 11/16] Fix version

---
 VERSION | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/VERSION b/VERSION
index 7d5c902..ee74734 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.1
+4.1.0
-- 
2.44.0


From 7da9d112af869533c29ab19cee07013e94c8fac2 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Tue, 8 Oct 2019 14:13:47 +0300
Subject: [PATCH 12/16] Mention CACert, GOPRIVATE and go.mod-replace during
 installation

---
 INSTALL       | 20 ++++++++++++++++----
 download.texi | 26 ++++++++++++++++++++------
 2 files changed, 36 insertions(+), 10 deletions(-)

diff --git a/INSTALL b/INSTALL
index 690ba98..06e6e67 100644
--- a/INSTALL
+++ b/INSTALL
@@ -35,10 +35,6 @@ like this:
     $ go run main.go
     f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 
-GoGOST is also go-get-able. For example to use streebog256 utility:
-
-    $ go get go.cypherpunks.ru/gogost/cmd/streebog256
-
 You have to verify downloaded tarballs integrity and authenticity to be
 sure that you retrieved trusted and untampered software. GNU Privacy
 Guard is used for that purpose.
@@ -54,3 +50,19 @@ resources.
     Look in PUBKEY.asc file.
     $ gpg --auto-key-locate dane --locate-keys gogost at cypherpunks dot ru
     $ gpg --auto-key-locate wkd --locate-keys gogost at cypherpunks dot ru
+
+GoGOST is also go-get-able. For example to use streebog256 utility:
+
+    $ go get go.cypherpunks.ru/gogost/cmd/streebog256
+
+go.cypherpunks.ru uses CACert.org certificate authority, that is not
+included by default in some operating system distributions and probably
+you have to install it in your system, because "go get" uses HTTPS
+connections. If you have issues using either sum.golang.org or
+proxy.golang.org, then you can disable their usage with
+GOPRIVATE=go.cypherpunks.ru/gogost environment variable.
+
+Also you can use "replace" feature inside your go.mod, like:
+
+    require go.cypherpunks.ru/gogost/v4 v4.1.0
+    replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.1.0/src/go.cypherpunks.ru/gogost/v4
diff --git a/download.texi b/download.texi
index bfdc5bc..0110f45 100644
--- a/download.texi
+++ b/download.texi
@@ -42,12 +42,6 @@ $ go run main.go
 f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 @end verbatim
 
-GoGOST is also @command{go get}-able. For example to use
-@command{streebog256} utility:
-@verbatim
-$ go get go.cypherpunks.ru/gogost/cmd/streebog256
-@end verbatim
-
 @multitable {XXXXX} {XXXX-XX-XX} {XXXX KiB} {link sign} {xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx} {xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx}
 @headitem Version @tab Date @tab Size @tab Tarball @tab SHA256 checksum @tab Streebog-256 checksum
 
@@ -113,6 +107,26 @@ $ gpg --auto-key-locate wkd --locate-keys gogost at cypherpunks dot ru
 
 @end itemize
 
+GoGOST is also @command{go get}-able. For example to use
+@command{streebog256} utility:
+@verbatim
+$ go get go.cypherpunks.ru/gogost/cmd/streebog256
+@end verbatim
+
+@code{go.cypherpunks.ru} uses @url{https://www.cacert.org/, CACert.org}
+certificate authority, that is not included by default in some operating
+system distributions and probably you have to install it in your system,
+because @command{go get} uses HTTPS connections. If you have issues
+using either @code{sum.golang.org} or @code{proxy.golang.org}, then you
+can disable their usage with @env{GOPRIVATE=go.cypherpunks.ru/gogost}
+environment variable.
+
+Also you can use @code{replace} feature inside your @file{go.mod}, like:
+@verbatim
+require go.cypherpunks.ru/gogost/v4 v4.1.0
+replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.1.0/src/go.cypherpunks.ru/gogost/v4
+@end verbatim
+
 You can obtain development source code by cloning
 @url{http://git-scm.com/, Git}
 @url{https://git.cypherpunks.ru/cgit.cgi/gogost.git/}.
-- 
2.44.0


From 7d43d5553eb4514fae95200be4033cbe6757b14f Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Wed, 9 Oct 2019 16:09:43 +0300
Subject: [PATCH 13/16] Direct link to Git repository

---
 download.texi | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/download.texi b/download.texi
index 0110f45..e264247 100644
--- a/download.texi
+++ b/download.texi
@@ -127,6 +127,5 @@ require go.cypherpunks.ru/gogost/v4 v4.1.0
 replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.1.0/src/go.cypherpunks.ru/gogost/v4
 @end verbatim
 
-You can obtain development source code by cloning
-@url{http://git-scm.com/, Git}
-@url{https://git.cypherpunks.ru/cgit.cgi/gogost.git/}.
+You can obtain development source code with
+@command{git clone git://git.cypherpunks.ru/gogost.git}.
-- 
2.44.0


From 1072e0c400df930802a114c8f76b477ae934738b Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 18 Oct 2019 11:00:29 +0300
Subject: [PATCH 14/16] Mention IKETREE the same as ESPTREE

---
 README    | 2 +-
 news.texi | 2 +-
 www.texi  | 2 +-
 3 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/README b/README
index 2f37487..d3208ba 100644
--- a/README
+++ b/README
@@ -20,7 +20,7 @@ GOST is GOvernment STandard of Russian Federation (and Soviet Union).
 * GOST R 34.13-2015 padding methods
 * MGM AEAD mode for 64 and 128 bit ciphers
 * TLSTREE keyscheduling function
-* ESPTREE keyscheduling function
+* ESPTREE/IKETREE (IKE* is the same as ESP*) keyscheduling function
 
 Known problems:
 
diff --git a/news.texi b/news.texi
index 12acd2e..7e09a27 100644
--- a/news.texi
+++ b/news.texi
@@ -6,7 +6,7 @@
 @anchor{Release 4.1.0}
 @item 4.1.0
     @itemize
-    @item @code{ESPTREE} implementation
+    @item @code{ESPTREE}/@code{IKETREE} implementation
     @item @code{CurveIdtc26gost34102012256paramSetB},
         @code{CurveIdtc26gost34102012256paramSetC},
         @code{CurveIdtc26gost34102012256paramSetD} curve aliases
diff --git a/www.texi b/www.texi
index 116cf20..efacc32 100644
--- a/www.texi
+++ b/www.texi
@@ -50,7 +50,7 @@ Currently supported algorithms are:
 @item GOST R 34.13-2015 padding methods
 @item MGM AEAD mode for 64 and 128 bit ciphers
 @item TLSTREE keyscheduling function
-@item ESPTREE keyscheduling function
+@item ESPTREE/IKETREE (IKE* is the same as ESP*) keyscheduling function
 @end itemize
 
 Please send questions, bug reports and patches to
-- 
2.44.0


From ce6c45e481a59d843a3b9caab55608c738aac2f4 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 18 Oct 2019 10:59:08 +0300
Subject: [PATCH 15/16] PRF_IPSEC_PRFPLUS_GOSTR3411_2012_{256,512}

---
 INSTALL              | 18 +++++-----
 NEWS                 |  6 +++-
 VERSION              |  2 +-
 download.texi        | 18 +++++-----
 makedist.sh          |  1 +
 news.texi            |  8 +++++
 prfplus/gost.go      | 46 +++++++++++++++++++++++++
 prfplus/gost_test.go | 81 ++++++++++++++++++++++++++++++++++++++++++++
 prfplus/plus.go      | 47 +++++++++++++++++++++++++
 9 files changed, 207 insertions(+), 20 deletions(-)
 create mode 100644 prfplus/gost.go
 create mode 100644 prfplus/gost_test.go
 create mode 100644 prfplus/plus.go

diff --git a/INSTALL b/INSTALL
index 06e6e67..22565ef 100644
--- a/INSTALL
+++ b/INSTALL
@@ -1,19 +1,19 @@
 Preferable way is to download tarball with the signature from official
 website and, for example, run tests with benchmarks:
 
-    $ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz
-    $ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz.sig
-    $ gpg --verify gogost-4.1.0.tar.xz.sig gogost-4.1.0.tar.xz
-    $ xz -d < gogost-4.1.0.tar.xz | tar xf -
-    $ make -C gogost-4.1.0 all bench
-    $ echo hello world | ./gogost-4.1.0/streebog256
+    $ wget http://gogost.cypherpunks.ru/gogost-4.2.0.tar.xz
+    $ wget http://gogost.cypherpunks.ru/gogost-4.2.0.tar.xz.sig
+    $ gpg --verify gogost-4.2.0.tar.xz.sig gogost-4.2.0.tar.xz
+    $ xz -d < gogost-4.2.0.tar.xz | tar xf -
+    $ make -C gogost-4.2.0 all bench
+    $ echo hello world | ./gogost-4.2.0/streebog256
     f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 
 And then you can include its source code in your project for example
 like this:
 
     $ mkdir -p myproj/src
-    $ cp -r gogost-4.1.0/src/go.cypherpunks.ru myproj/src
+    $ cp -r gogost-4.2.0/src/go.cypherpunks.ru myproj/src
     $ export GOPATH=$PWD/myproj
     $ cd myproj/src
     $ cat > main.go <<EOF
@@ -64,5 +64,5 @@ GOPRIVATE=go.cypherpunks.ru/gogost environment variable.
 
 Also you can use "replace" feature inside your go.mod, like:
 
-    require go.cypherpunks.ru/gogost/v4 v4.1.0
-    replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.1.0/src/go.cypherpunks.ru/gogost/v4
+    require go.cypherpunks.ru/gogost/v4 v4.2.0
+    replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.2.0/src/go.cypherpunks.ru/gogost/v4
diff --git a/NEWS b/NEWS
index 5b13d25..1723442 100644
--- a/NEWS
+++ b/NEWS
@@ -1,5 +1,9 @@
+4.2.0:
+    * PRF_IPSEC_PRFPLUS_GOSTR3411_2012_{256,512} implementation
+    * Generic prf+ function (taken from IKEv2) implementation
+
 4.1.0:
-    * ESPTREE implementation
+    * ESPTREE/IKETREE implementation
     * CurveIdtc26gost34102012256paramSetB, CurveIdtc26gost34102012256paramSetC,
       CurveIdtc26gost34102012256paramSetD curve aliases
     * Forbid any later GNU GPL version autousage
diff --git a/VERSION b/VERSION
index ee74734..6aba2b2 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.1.0
+4.2.0
diff --git a/download.texi b/download.texi
index e264247..fde8fda 100644
--- a/download.texi
+++ b/download.texi
@@ -5,12 +5,12 @@ Preferable way is to download tarball with the signature from
 website and, for example, run tests with benchmarks:
 
 @verbatim
-$ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz
-$ wget http://gogost.cypherpunks.ru/gogost-4.1.0.tar.xz.sig
-$ gpg --verify gogost-4.1.0.tar.xz.sig gogost-4.1.0.tar.xz
-$ xz -d < gogost-4.1.0.tar.xz | tar xf -
-$ make -C gogost-4.1.0 all bench
-$ echo hello world | ./gogost-4.1.0/streebog256
+$ wget http://gogost.cypherpunks.ru/gogost-4.2.0.tar.xz
+$ wget http://gogost.cypherpunks.ru/gogost-4.2.0.tar.xz.sig
+$ gpg --verify gogost-4.2.0.tar.xz.sig gogost-4.2.0.tar.xz
+$ xz -d < gogost-4.2.0.tar.xz | tar xf -
+$ make -C gogost-4.2.0 all bench
+$ echo hello world | ./gogost-4.2.0/streebog256
 f72018189a5cfb803dbe1f2149cf554c40093d8e7f81c21e08ac5bcd09d9934d
 @end verbatim
 
@@ -19,7 +19,7 @@ like this:
 
 @verbatim
 $ mkdir -p myproj/src
-$ cp -r gogost-4.1.0/src/go.cypherpunks.ru myproj/src
+$ cp -r gogost-4.2.0/src/go.cypherpunks.ru myproj/src
 $ export GOPATH=$PWD/myproj
 $ cd myproj/src
 $ cat > main.go <<EOF
@@ -123,8 +123,8 @@ environment variable.
 
 Also you can use @code{replace} feature inside your @file{go.mod}, like:
 @verbatim
-require go.cypherpunks.ru/gogost/v4 v4.1.0
-replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.1.0/src/go.cypherpunks.ru/gogost/v4
+require go.cypherpunks.ru/gogost/v4 v4.2.0
+replace go.cypherpunks.ru/gogost/v4 => /home/stargrave/gogost-4.2.0/src/go.cypherpunks.ru/gogost/v4
 @end verbatim
 
 You can obtain development source code with
diff --git a/makedist.sh b/makedist.sh
index 7ed9a15..879a373 100755
--- a/makedist.sh
+++ b/makedist.sh
@@ -22,6 +22,7 @@ mv \
     gost341264 \
     gost3413 \
     mgm \
+    prfplus \
     cmd internal gogost.go go.mod go.sum src/$mod_name
 
 mkdir -p src/golang.org/x/crypto
diff --git a/news.texi b/news.texi
index 7e09a27..01fb655 100644
--- a/news.texi
+++ b/news.texi
@@ -3,6 +3,14 @@
 
 @table @strong
 
+@anchor{Release 4.2.0}
+@item 4.2.0
+    @itemize
+    @item @code{PRF_IPSEC_PRFPLUS_GOSTR3411_2012_@{256,512@}} implementation
+    @item Generic @code{prf+} function (taken from IKEv2
+        (@url{https://tools.ietf.org/html/rfc5831.html, RFC 7296}))
+    @end itemize
+
 @anchor{Release 4.1.0}
 @item 4.1.0
     @itemize
diff --git a/prfplus/gost.go b/prfplus/gost.go
new file mode 100644
index 0000000..659b5b4
--- /dev/null
+++ b/prfplus/gost.go
@@ -0,0 +1,46 @@
+// 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/>.
+
+// PRF_IPSEC_PRFPLUS_GOSTR3411_2012_{256,512} as defined in R 50.1.113-2016.
+package prfplus
+
+import (
+	"crypto/hmac"
+	"hash"
+
+	"go.cypherpunks.ru/gogost/v4/gost34112012256"
+	"go.cypherpunks.ru/gogost/v4/gost34112012512"
+)
+
+type PRFIPsecPRFPlusGOSTR34112012 struct{ h hash.Hash }
+
+func NewPRFIPsecPRFPlusGOSTR34112012256(key []byte) PRFForPlus {
+	return PRFIPsecPRFPlusGOSTR34112012{hmac.New(gost34112012256.New, key)}
+}
+
+func NewPRFIPsecPRFPlusGOSTR34112012512(key []byte) PRFForPlus {
+	return PRFIPsecPRFPlusGOSTR34112012{hmac.New(gost34112012512.New, key)}
+}
+
+func (prf PRFIPsecPRFPlusGOSTR34112012) BlockSize() int {
+	return prf.h.Size()
+}
+
+func (prf PRFIPsecPRFPlusGOSTR34112012) Derive(salt []byte) []byte {
+	prf.h.Write(salt)
+	sum := prf.h.Sum(nil)
+	prf.h.Reset()
+	return sum
+}
diff --git a/prfplus/gost_test.go b/prfplus/gost_test.go
new file mode 100644
index 0000000..300d76c
--- /dev/null
+++ b/prfplus/gost_test.go
@@ -0,0 +1,81 @@
+// 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 prfplus
+
+import (
+	"bytes"
+	"testing"
+)
+
+func TestPRFIPsecPRFPlusGOSTR34112012256(t *testing.T) {
+	prf := NewPRFIPsecPRFPlusGOSTR34112012256([]byte{
+		0xC9, 0xA9, 0xA7, 0x73, 0x20, 0xE2, 0xCC, 0x55,
+		0x9E, 0xD7, 0x2D, 0xCE, 0x6F, 0x47, 0xE2, 0x19,
+		0x2C, 0xCE, 0xA9, 0x5F, 0xA6, 0x48, 0x67, 0x05,
+		0x82, 0xC0, 0x54, 0xC0, 0xEF, 0x36, 0xC2, 0x21,
+	})
+	dst := make([]byte, 64)
+	PRFPlus(prf, dst, []byte{
+		0x01, 0x26, 0xBD, 0xB8, 0x78, 0x00, 0x1D, 0x80,
+		0x60, 0x3C, 0x85, 0x44, 0xC7, 0x27, 0x01, 0x00,
+	})
+	if bytes.Compare(dst, []byte{
+		0x2D, 0xE5, 0xEE, 0x84, 0xE1, 0x3D, 0x7B, 0xE5,
+		0x36, 0x16, 0x67, 0x39, 0x13, 0x37, 0x0A, 0xB0,
+		0x54, 0xC0, 0x74, 0xB7, 0x9B, 0x69, 0xA8, 0xA8,
+		0x46, 0x82, 0xA9, 0xF0, 0x4F, 0xEC, 0xD5, 0x87,
+		0x29, 0xF6, 0x0D, 0xDA, 0x45, 0x7B, 0xF2, 0x19,
+		0xAA, 0x2E, 0xF9, 0x5D, 0x7A, 0x59, 0xBE, 0x95,
+		0x4D, 0xE0, 0x08, 0xF4, 0xA5, 0x0D, 0x50, 0x4D,
+		0xBD, 0xB6, 0x90, 0xBE, 0x68, 0x06, 0x01, 0x53,
+	}) != 0 {
+		t.FailNow()
+	}
+}
+
+func TestPRFIPsecPRFPlusGOSTR34112012512(t *testing.T) {
+	prf := NewPRFIPsecPRFPlusGOSTR34112012512([]byte{
+		0xC9, 0xA9, 0xA7, 0x73, 0x20, 0xE2, 0xCC, 0x55,
+		0x9E, 0xD7, 0x2D, 0xCE, 0x6F, 0x47, 0xE2, 0x19,
+		0x2C, 0xCE, 0xA9, 0x5F, 0xA6, 0x48, 0x67, 0x05,
+		0x82, 0xC0, 0x54, 0xC0, 0xEF, 0x36, 0xC2, 0x21,
+	})
+	dst := make([]byte, 128)
+	PRFPlus(prf, dst, []byte{
+		0x01, 0x26, 0xBD, 0xB8, 0x78, 0x00, 0x1D, 0x80,
+		0x60, 0x3C, 0x85, 0x44, 0xC7, 0x27, 0x01, 0x00,
+	})
+	if bytes.Compare(dst, []byte{
+		0x5D, 0xA6, 0x71, 0x43, 0xA5, 0xF1, 0x2A, 0x6D,
+		0x6E, 0x47, 0x42, 0x59, 0x6F, 0x39, 0x24, 0x3F,
+		0xCC, 0x61, 0x57, 0x45, 0x91, 0x5B, 0x32, 0x59,
+		0x10, 0x06, 0xFF, 0x78, 0xA2, 0x08, 0x63, 0xD5,
+		0xF8, 0x8E, 0x4A, 0xFC, 0x17, 0xFB, 0xBE, 0x70,
+		0xB9, 0x50, 0x95, 0x73, 0xDB, 0x00, 0x5E, 0x96,
+		0x26, 0x36, 0x98, 0x46, 0xCB, 0x86, 0x19, 0x99,
+		0x71, 0x6C, 0x16, 0x5D, 0xD0, 0x6A, 0x15, 0x85,
+		0x48, 0x34, 0x49, 0x5A, 0x43, 0x74, 0x6C, 0xB5,
+		0x3F, 0x0A, 0xBA, 0x3B, 0xC4, 0x6E, 0xBC, 0xF8,
+		0x77, 0x3C, 0xA6, 0x4A, 0xD3, 0x43, 0xC1, 0x22,
+		0xEE, 0x2A, 0x57, 0x75, 0x57, 0x03, 0x81, 0x57,
+		0xEE, 0x9C, 0x38, 0x8D, 0x96, 0xEF, 0x71, 0xD5,
+		0x8B, 0xE5, 0xC1, 0xEF, 0xA1, 0xAF, 0xA9, 0x5E,
+		0xBE, 0x83, 0xE3, 0x9D, 0x00, 0xE1, 0x9A, 0x5D,
+		0x03, 0xDC, 0xD6, 0x0A, 0x01, 0xBC, 0xA8, 0xE3,
+	}) != 0 {
+		t.FailNow()
+	}
+}
diff --git a/prfplus/plus.go b/prfplus/plus.go
new file mode 100644
index 0000000..84ce70c
--- /dev/null
+++ b/prfplus/plus.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 prfplus
+
+type PRFForPlus interface {
+	BlockSize() int
+	Derive(salt []byte) []byte
+}
+
+// prf+ function as defined in RFC 7296 (IKEv2)
+func PRFPlus(prf PRFForPlus, dst, salt []byte) {
+	in := make([]byte, prf.BlockSize()+len(salt)+1)
+	in[len(in)-1] = byte(0x01)
+	copy(in[prf.BlockSize():], salt)
+	copy(in[:prf.BlockSize()], prf.Derive(in[prf.BlockSize():]))
+	copy(dst, in[:prf.BlockSize()])
+	n := len(dst) / prf.BlockSize()
+	if n == 0 {
+		return
+	}
+	if n*prf.BlockSize() != len(dst) {
+		n++
+	}
+	n--
+	out := dst[prf.BlockSize():]
+	for i := 0; i < n; i++ {
+		in[len(in)-1] = byte(i + 2)
+		copy(in[:prf.BlockSize()], prf.Derive(in))
+		copy(out, in[:prf.BlockSize()])
+		if i+1 != n {
+			out = out[prf.BlockSize():]
+		}
+	}
+}
-- 
2.44.0


From 0da4d634ac5368d024489baf4bdd5d422b84dd84 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Fri, 18 Oct 2019 15:57:26 +0300
Subject: [PATCH 16/16] Slightly more descriptive errors

---
 gost28147/mac.go              |  4 ++--
 gost3410/curve.go             |  4 ++--
 gost3410/private.go           |  5 +++--
 gost3410/public.go            | 11 +++++++----
 gost3410/vko2001.go           |  2 +-
 internal/gost34112012/hash.go |  8 +++++---
 mgm/mode.go                   |  6 +++---
 7 files changed, 23 insertions(+), 17 deletions(-)

diff --git a/gost28147/mac.go b/gost28147/mac.go
index bcfd52c..b49bc7d 100644
--- a/gost28147/mac.go
+++ b/gost28147/mac.go
@@ -42,10 +42,10 @@ type MAC struct {
 // following ones are fed to Write function.
 func (c *Cipher) NewMAC(size int, iv []byte) (*MAC, error) {
 	if size == 0 || size > 8 {
-		return nil, errors.New("Invalid tag size")
+		return nil, errors.New("gogost/gost28147: invalid tag size")
 	}
 	if len(iv) != BlockSize {
-		return nil, errors.New("iv length is not equal to blocksize")
+		return nil, errors.New("gogost/gost28147: len(iv) != 8")
 	}
 	m := MAC{c: c, size: size, iv: iv}
 	n2, n1 := block2nvs(iv)
diff --git a/gost3410/curve.go b/gost3410/curve.go
index 47f964b..b5fa052 100644
--- a/gost3410/curve.go
+++ b/gost3410/curve.go
@@ -79,7 +79,7 @@ func NewCurve(p, q, a, b, x, y, e, d *big.Int) (*Curve, error) {
 	r2.Mod(r2, c.P)
 	c.pos(r2)
 	if r1.Cmp(r2) != 0 {
-		return nil, errors.New("Invalid curve parameters")
+		return nil, errors.New("gogost/gost3410: invalid curve parameters")
 	}
 	if e != nil && d != nil {
 		c.E = e
@@ -131,7 +131,7 @@ func (c *Curve) add(p1x, p1y, p2x, p2y *big.Int) {
 
 func (c *Curve) Exp(degree, xS, yS *big.Int) (*big.Int, *big.Int, error) {
 	if degree.Cmp(zero) == 0 {
-		return nil, nil, errors.New("Bad degree value")
+		return nil, nil, errors.New("gogost/gost3410: zero degree value")
 	}
 	dg := big.NewInt(0).Sub(degree, bigInt1)
 	tx := big.NewInt(0).Set(xS)
diff --git a/gost3410/private.go b/gost3410/private.go
index 045c818..231f45e 100644
--- a/gost3410/private.go
+++ b/gost3410/private.go
@@ -18,6 +18,7 @@ package gost3410
 import (
 	"crypto"
 	"errors"
+	"fmt"
 	"io"
 	"math/big"
 )
@@ -30,7 +31,7 @@ type PrivateKey struct {
 
 func NewPrivateKey(curve *Curve, mode Mode, raw []byte) (*PrivateKey, error) {
 	if len(raw) != int(mode) {
-		return nil, errors.New("Invalid private key length")
+		return nil, fmt.Errorf("gogost/gost3410: len(key) != %d", mode)
 	}
 	key := make([]byte, int(mode))
 	for i := 0; i < len(key); i++ {
@@ -38,7 +39,7 @@ func NewPrivateKey(curve *Curve, mode Mode, raw []byte) (*PrivateKey, error) {
 	}
 	k := bytes2big(key)
 	if k.Cmp(zero) == 0 {
-		return nil, errors.New("Zero private key")
+		return nil, errors.New("gogost/gost3410: zero private key")
 	}
 	return &PrivateKey{curve, mode, k}, nil
 }
diff --git a/gost3410/public.go b/gost3410/public.go
index 08e1414..de2d858 100644
--- a/gost3410/public.go
+++ b/gost3410/public.go
@@ -16,7 +16,7 @@
 package gost3410
 
 import (
-	"errors"
+	"fmt"
 	"math/big"
 )
 
@@ -30,7 +30,7 @@ type PublicKey struct {
 func NewPublicKey(curve *Curve, mode Mode, raw []byte) (*PublicKey, error) {
 	key := make([]byte, 2*int(mode))
 	if len(raw) != len(key) {
-		return nil, errors.New("Invalid public key length")
+		return nil, fmt.Errorf("gogost/gost3410: len(key) != %d", len(key))
 	}
 	for i := 0; i < len(key); i++ {
 		key[i] = raw[len(raw)-i-1]
@@ -54,11 +54,14 @@ func (pub *PublicKey) Raw() []byte {
 
 func (pub *PublicKey) VerifyDigest(digest, signature []byte) (bool, error) {
 	if len(signature) != 2*int(pub.Mode) {
-		return false, errors.New("Invalid signature length")
+		return false, fmt.Errorf("gogost/gost3410: len(signature) != %d", 2*int(pub.Mode))
 	}
 	s := bytes2big(signature[:pub.Mode])
 	r := bytes2big(signature[pub.Mode:])
-	if r.Cmp(zero) <= 0 || r.Cmp(pub.C.Q) >= 0 || s.Cmp(zero) <= 0 || s.Cmp(pub.C.Q) >= 0 {
+	if r.Cmp(zero) <= 0 ||
+		r.Cmp(pub.C.Q) >= 0 ||
+		s.Cmp(zero) <= 0 ||
+		s.Cmp(pub.C.Q) >= 0 {
 		return false, nil
 	}
 	e := bytes2big(digest)
diff --git a/gost3410/vko2001.go b/gost3410/vko2001.go
index ed49d8f..c950280 100644
--- a/gost3410/vko2001.go
+++ b/gost3410/vko2001.go
@@ -27,7 +27,7 @@ import (
 // UKM is user keying material, also called VKO-factor.
 func (prv *PrivateKey) KEK2001(pub *PublicKey, ukm *big.Int) ([]byte, error) {
 	if prv.Mode != Mode2001 {
-		return nil, errors.New("KEK2001 can not be used in Mode2012")
+		return nil, errors.New("gogost/gost3410: KEK2001 can not be used in Mode2012")
 	}
 	key, err := prv.KEK(pub, ukm)
 	if err != nil {
diff --git a/internal/gost34112012/hash.go b/internal/gost34112012/hash.go
index 5f6b707..2c1b4b9 100644
--- a/internal/gost34112012/hash.go
+++ b/internal/gost34112012/hash.go
@@ -21,6 +21,7 @@ import (
 	"bytes"
 	"encoding/binary"
 	"errors"
+	"fmt"
 )
 
 const (
@@ -426,11 +427,12 @@ func (h *Hash) MarshalBinary() (data []byte, err error) {
 }
 
 func (h *Hash) UnmarshalBinary(data []byte) error {
-	if len(data) < len(MarshaledName)+1+8+3*BlockSize {
-		return errors.New("too short data")
+	expectedLen := len(MarshaledName) + 1 + 8 + 3*BlockSize
+	if len(data) < expectedLen {
+		return fmt.Errorf("gogost/internal/gost34112012: len(data) != %d", expectedLen)
 	}
 	if !bytes.HasPrefix(data, []byte(MarshaledName)) {
-		return errors.New("no hash name prefix")
+		return errors.New("gogost/internal/gost34112012: no hash name prefix")
 	}
 	idx := len(MarshaledName)
 	h.size = int(data[idx])
diff --git a/mgm/mode.go b/mgm/mode.go
index fdbfa42..7857968 100644
--- a/mgm/mode.go
+++ b/mgm/mode.go
@@ -61,10 +61,10 @@ type MGM struct {
 func NewMGM(cipher cipher.Block, tagSize int) (cipher.AEAD, error) {
 	blockSize := cipher.BlockSize()
 	if !(blockSize == 8 || blockSize == 16) {
-		return nil, errors.New("MGM supports only 64/128 blocksizes")
+		return nil, errors.New("gogost/mgm: only 64/128 blocksizes allowed")
 	}
 	if tagSize < 4 || tagSize > blockSize {
-		return nil, errors.New("invalid tag size")
+		return nil, errors.New("gogost/mgm: invalid tag size")
 	}
 	mgm := MGM{
 		maxSize:   uint64(1<<uint(blockSize*8/2) - 1),
@@ -242,7 +242,7 @@ func (mgm *MGM) Open(dst, nonce, ciphertext, additionalData []byte) ([]byte, err
 	copy(mgm.icn, nonce)
 	mgm.auth(mgm.sum, ct, additionalData)
 	if !hmac.Equal(mgm.sum[:mgm.tagSize], ciphertext[len(ciphertext)-mgm.tagSize:]) {
-		return nil, errors.New("invalid authentication tag")
+		return nil, errors.New("gogost/mgm: invalid authentication tag")
 	}
 	mgm.crypt(out, ct)
 	return ret, nil
-- 
2.44.0