From 641114ba28a411c561956b5524534d3981188f11 Mon Sep 17 00:00:00 2001
From: Vlad <gluk256@gmail.com>
Date: Wed, 19 Oct 2016 12:51:44 +0200
Subject: [PATCH] whisper: fixed math/rand.Read() issue

---
 whisper/whisperv5/filter.go       |  2 +-
 whisper/whisperv5/filter_test.go  | 28 ++++++++++------------------
 whisper/whisperv5/message.go      | 18 +++++++++++++++++-
 whisper/whisperv5/message_test.go | 24 ++++++------------------
 4 files changed, 34 insertions(+), 38 deletions(-)

diff --git a/whisper/whisperv5/filter.go b/whisper/whisperv5/filter.go
index 3ca1c84472..31c7aed0f1 100644
--- a/whisper/whisperv5/filter.go
+++ b/whisper/whisperv5/filter.go
@@ -96,7 +96,7 @@ func (fs *Filters) NotifyWatchers(env *Envelope, messageCode uint64) {
 	}
 	fs.mutex.RUnlock() // we need to unlock before calling addDecryptedMessage
 
-	if msg != nil {
+	if msg != nil && fs.whisper != nil {
 		fs.whisper.addDecryptedMessage(msg)
 	}
 }
diff --git a/whisper/whisperv5/filter_test.go b/whisper/whisperv5/filter_test.go
index e92b528d3e..71b6b04298 100644
--- a/whisper/whisperv5/filter_test.go
+++ b/whisper/whisperv5/filter_test.go
@@ -16,25 +16,17 @@
 
 package whisperv5
 
-/*
 import "testing"
 
-var topicXxxxxxxxxxxTests = []struct {
-	topic TopicType
-	str   string
-}{
-	{topic: TopicType{0x00, 0x00, 0x00, 0x00}, str: "0x00000000"},
-	{topic: TopicType{0x00, 0x7f, 0x80, 0xff}, str: "0x007f80ff"},
-	{topic: TopicType{0xff, 0x80, 0x7f, 0x00}, str: "0xff807f00"},
-	{topic: TopicType{0xf2, 0x6e, 0x77, 0x79}, str: "0xf26e7779"},
-}
-
-func TestXxxxxxxxxxxx(x *testing.T) {
-	for i, tst := range topicStringTests {
-		s := tst.topic.String()
-		if s != tst.str {
-			x.Errorf("failed test %d: have %s, want %s.", i, s, tst.str)
-		}
+func TestFilters(x *testing.T) {
+	filters := NewFilters(nil)
+	f := Filter{}
+	filters.Install(f)
+	i := filters.Install(f)
+	if i == 0 {
+		x.Errorf("failed install")
+		return
 	}
+
+	// todo: test Install, Uninstall, Get
 }
-*/
diff --git a/whisper/whisperv5/message.go b/whisper/whisperv5/message.go
index 176676caca..35ce949ab3 100644
--- a/whisper/whisperv5/message.go
+++ b/whisper/whisperv5/message.go
@@ -130,7 +130,7 @@ func (msg *SentMessage) appendPadding(params *MessageParams) {
 			panic("please fix the padding algorithm before releasing new version")
 		}
 		buf := make([]byte, padSize)
-		mrand.Read(buf[1:])
+		randomize(buf[1:]) // change to: err = mrand.Read(buf[1:])
 		buf[0] = byte(padSize)
 		if params.Padding != nil {
 			copy(buf[1:], params.Padding)
@@ -360,3 +360,19 @@ func (msg *ReceivedMessage) hash() []byte {
 	}
 	return crypto.Keccak256(msg.Raw)
 }
+
+// rand.Rand provides a Read method in Go 1.7 and later,
+// but we can't use it yet.
+func randomize(b []byte) {
+	cnt := 0
+	val := mrand.Int63()
+	for n := 0; n < len(b); n++ {
+		b[n] = byte(val)
+		val >>= 8
+		cnt++
+		if cnt >= 7 {
+			cnt = 0
+			val = mrand.Int63()
+		}
+	}
+}
diff --git a/whisper/whisperv5/message_test.go b/whisper/whisperv5/message_test.go
index 3e6fc701cd..65487bef4c 100644
--- a/whisper/whisperv5/message_test.go
+++ b/whisper/whisperv5/message_test.go
@@ -30,16 +30,13 @@ func copyFromBuf(dst []byte, src []byte, beg int) int {
 	return beg + len(dst)
 }
 
-func generateMessageParams() (*MessageParams, error) {
+func generateMessageParams() (*MessageParams, err error) {
 	buf := make([]byte, 1024)
-	_, err := rand.Read(buf)
-	if err != nil {
-		return nil, err
-	}
+	randomize(buf)
+	sz := rand.Intn(400)
 
 	var p MessageParams
 	p.TTL = uint32(rand.Intn(1024))
-	sz := rand.Intn(400)
 	p.Payload = make([]byte, sz)
 	p.Padding = make([]byte, padSizeLimitUpper)
 	p.KeySym = make([]byte, aesKeyLength)
@@ -49,7 +46,6 @@ func generateMessageParams() (*MessageParams, error) {
 	b = copyFromBuf(p.Padding, buf, b)
 	b = copyFromBuf(p.KeySym, buf, b)
 	p.Topic = BytesToTopic(buf[b:])
-
 	p.Src, err = crypto.GenerateKey()
 	if err != nil {
 		return nil, err
@@ -184,16 +180,8 @@ func TestMessageSeal(x *testing.T) {
 	params.TTL = 1
 	aesnonce := make([]byte, 12)
 	salt := make([]byte, 12)
-	_, err = rand.Read(aesnonce)
-	if err != nil {
-		x.Errorf("failed generate aesnonce with seed %d: %s.", seed, err)
-		return
-	}
-	_, err = rand.Read(salt)
-	if err != nil {
-		x.Errorf("failed generate salt with seed %d: %s.", seed, err)
-		return
-	}
+	randomize(aesnonce)
+	randomize(salt)
 
 	env := NewEnvelope(params.TTL, params.Topic, salt, aesnonce, msg)
 	if err != nil {
@@ -219,7 +207,7 @@ func TestMessageSeal(x *testing.T) {
 	env.Seal(params)
 	env.calculatePoW(0)
 	pow = env.PoW()
-	if pow < 1000 {
+	if pow < 2*target {
 		// this depends on deterministic choice of seed (1976726903)
 		x.Errorf("failed Wrap with seed %d: pow too small %f.", seed, pow)
 		return