From 9f3355e3239fed2b0110b0724e7ba1ed509b8a19 Mon Sep 17 00:00:00 2001
From: Sergey Matveev <stargrave@stargrave.org>
Date: Wed, 22 Jan 2020 16:37:58 +0300
Subject: [PATCH] Panic on all possible hash write errors

---
 VERSION                 |  2 +-
 cmd/streebog256/main.go |  4 +++-
 cmd/streebog512/main.go |  4 +++-
 gost3410/vko2001.go     |  4 +++-
 gost3410/vko2012.go     |  8 ++++++--
 gost34112012256/kdf.go  | 24 ++++++++++++++++++------
 install.texi            |  2 +-
 news.texi               |  4 ++++
 prfplus/gost.go         |  4 +++-
 9 files changed, 42 insertions(+), 14 deletions(-)

diff --git a/VERSION b/VERSION
index af8c8ec..f2c6cb6 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.2.2
+4.2.3
diff --git a/cmd/streebog256/main.go b/cmd/streebog256/main.go
index efaae81..9db7c47 100644
--- a/cmd/streebog256/main.go
+++ b/cmd/streebog256/main.go
@@ -38,6 +38,8 @@ func main() {
 		return
 	}
 	h := gost34112012256.New()
-	io.Copy(h, os.Stdin)
+	if _, err := io.Copy(h, os.Stdin); err != nil {
+		panic(err)
+	}
 	fmt.Println(hex.EncodeToString(h.Sum(nil)))
 }
diff --git a/cmd/streebog512/main.go b/cmd/streebog512/main.go
index d705064..052592f 100644
--- a/cmd/streebog512/main.go
+++ b/cmd/streebog512/main.go
@@ -38,6 +38,8 @@ func main() {
 		return
 	}
 	h := gost34112012512.New()
-	io.Copy(h, os.Stdin)
+	if _, err := io.Copy(h, os.Stdin); err != nil {
+		panic(err)
+	}
 	fmt.Println(hex.EncodeToString(h.Sum(nil)))
 }
diff --git a/gost3410/vko2001.go b/gost3410/vko2001.go
index 02f976f..c9aeada 100644
--- a/gost3410/vko2001.go
+++ b/gost3410/vko2001.go
@@ -34,6 +34,8 @@ func (prv *PrivateKey) KEK2001(pub *PublicKey, ukm *big.Int) ([]byte, error) {
 		return nil, err
 	}
 	h := gost341194.New(&gost28147.SboxIdGostR341194CryptoProParamSet)
-	h.Write(key)
+	if _, err = h.Write(key); err != nil {
+		return nil, err
+	}
 	return h.Sum(key[:0]), nil
 }
diff --git a/gost3410/vko2012.go b/gost3410/vko2012.go
index 01f3e85..78b9af5 100644
--- a/gost3410/vko2012.go
+++ b/gost3410/vko2012.go
@@ -30,7 +30,9 @@ func (prv *PrivateKey) KEK2012256(pub *PublicKey, ukm *big.Int) ([]byte, error)
 		return nil, err
 	}
 	h := gost34112012256.New()
-	h.Write(key)
+	if _, err = h.Write(key); err != nil {
+		return nil, err
+	}
 	return h.Sum(key[:0]), nil
 }
 
@@ -42,6 +44,8 @@ func (prv *PrivateKey) KEK2012512(pub *PublicKey, ukm *big.Int) ([]byte, error)
 		return nil, err
 	}
 	h := gost34112012512.New()
-	h.Write(key)
+	if _, err = h.Write(key); err != nil {
+		return nil, err
+	}
 	return h.Sum(key[:0]), nil
 }
diff --git a/gost34112012256/kdf.go b/gost34112012256/kdf.go
index 43c08ae..d818fb2 100644
--- a/gost34112012256/kdf.go
+++ b/gost34112012256/kdf.go
@@ -29,12 +29,24 @@ func NewKDF(key []byte) *KDF {
 }
 
 func (kdf *KDF) Derive(dst, label, seed []byte) (r []byte) {
-	kdf.h.Write([]byte{0x01})
-	kdf.h.Write(label)
-	kdf.h.Write([]byte{0x00})
-	kdf.h.Write(seed)
-	kdf.h.Write([]byte{0x01})
-	kdf.h.Write([]byte{0x00})
+	if _, err := kdf.h.Write([]byte{0x01}); err != nil {
+		panic(err)
+	}
+	if _, err := kdf.h.Write(label); err != nil {
+		panic(err)
+	}
+	if _, err := kdf.h.Write([]byte{0x00}); err != nil {
+		panic(err)
+	}
+	if _, err := kdf.h.Write(seed); err != nil {
+		panic(err)
+	}
+	if _, err := kdf.h.Write([]byte{0x01}); err != nil {
+		panic(err)
+	}
+	if _, err := kdf.h.Write([]byte{0x00}); err != nil {
+		panic(err)
+	}
 	r = kdf.h.Sum(dst)
 	kdf.h.Reset()
 	return r
diff --git a/install.texi b/install.texi
index 93c181f..7cf962c 100644
--- a/install.texi
+++ b/install.texi
@@ -1,7 +1,7 @@
 @node Download
 @unnumbered Download
 
-@set VERSION 4.2.2
+@set VERSION 4.2.3
 
 Preferable way is to download tarball with the signature from
 website and, for example, run tests with benchmarks:
diff --git a/news.texi b/news.texi
index eb34c76..d2d1e82 100644
--- a/news.texi
+++ b/news.texi
@@ -3,6 +3,10 @@
 
 @table @strong
 
+@anchor{Release 4.2.3}
+@item 4.2.3
+    Panic on all possible hash @code{Write} errors.
+
 @anchor{Release 4.2.2}
 @item 4.2.2
     More 34.10-2012 test vectors.
diff --git a/prfplus/gost.go b/prfplus/gost.go
index 86f4cac..4b1aed6 100644
--- a/prfplus/gost.go
+++ b/prfplus/gost.go
@@ -39,7 +39,9 @@ func (prf PRFIPsecPRFPlusGOSTR34112012) BlockSize() int {
 }
 
 func (prf PRFIPsecPRFPlusGOSTR34112012) Derive(salt []byte) []byte {
-	prf.h.Write(salt)
+	if _, err := prf.h.Write(salt); err != nil {
+		panic(err)
+	}
 	sum := prf.h.Sum(nil)
 	prf.h.Reset()
 	return sum
-- 
2.44.0