From: Jason A. Donenfeld <Jason@zx2c4.com>
Date: Sun, 3 Feb 2019 21:00:36 +0000 (+0100)
Subject: noise: store clamped key instead of raw key
X-Git-Tag: 0.0.20190409~122
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3af9aa88a310f7c2b86bae1ebb3ed3843424ce9e;p=thirdparty%2Fwireguard-go.git

noise: store clamped key instead of raw key
---

diff --git a/noise-helpers.go b/noise-helpers.go
index 1b2746c..af11f09 100644
--- a/noise-helpers.go
+++ b/noise-helpers.go
@@ -78,12 +78,14 @@ func setZero(arr []byte) {
 	}
 }
 
+func (sk *NoisePrivateKey) clamp() {
+	sk[0] &= 248
+	sk[31] = (sk[31] & 127) | 64
+}
+
 func newPrivateKey() (sk NoisePrivateKey, err error) {
-	// clamping: https://cr.yp.to/ecdh.html
 	_, err = rand.Read(sk[:])
-	sk[0] &= 248
-	sk[31] &= 127
-	sk[31] |= 64
+	sk.clamp()
 	return
 }
 
diff --git a/noise-types.go b/noise-types.go
index df6ee77..902905e 100644
--- a/noise-types.go
+++ b/noise-types.go
@@ -45,8 +45,10 @@ func (key NoisePrivateKey) Equals(tar NoisePrivateKey) bool {
 	return subtle.ConstantTimeCompare(key[:], tar[:]) == 1
 }
 
-func (key *NoisePrivateKey) FromHex(src string) error {
-	return loadExactHex(key[:], src)
+func (key *NoisePrivateKey) FromHex(src string) (err error) {
+	err = loadExactHex(key[:], src)
+	key.clamp()
+	return
 }
 
 func (key NoisePrivateKey) ToHex() string {