whisper: The filter's symmetric key hash wasn't properly set at init.

The consequence is that symmetric messages would not be delivered to
their intended recipients, because the comparison between two hashes
would be false.

whisper/whisperv5/filter.go

@@ -22,6 +22,7 @@ import (
 	"sync"
 
 	"github.com/ethereum/go-ethereum/common"
+	"github.com/ethereum/go-ethereum/crypto"
 	"github.com/ethereum/go-ethereum/log"
 )
 
@@ -68,6 +69,10 @@ func (fs *Filters) Install(watcher *Filter) (string, error) {
 		return "", fmt.Errorf("failed to generate unique ID")
 	}
 
+	if watcher.expectsSymmetricEncryption() {
+		watcher.SymKeyHash = crypto.Keccak256Hash(watcher.KeySym);
+	}
+
 	fs.watchers[id] = watcher
 	return id, err
 }

whisper/whisperv5/filter_test.go

@@ -132,6 +132,38 @@ func TestInstallFilters(t *testing.T) {
 	}
 }
 
+func TestInstallSymKeyGeneratesHash(t *testing.T) {
+	InitSingleTest()
+
+	w := New(&Config{})
+	filters := NewFilters(w)
+	filter, _ := generateFilter(t, true)
+
+	// save the current SymKeyHash for comparison
+	initialSymKeyHash := filter.SymKeyHash
+
+	// ensure the SymKeyHash is invalid, for Install to recreate it
+	var invalid common.Hash
+	filter.SymKeyHash = invalid
+
+	_, err := filters.Install(filter)
+
+	if err != nil {
+		t.Fatalf("Error installing the filter: %v", err);
+	}
+
+	identicalBytes := true
+	for i, b := range filter.SymKeyHash {
+		if b != initialSymKeyHash[i] {
+			identicalBytes = false
+			break
+		}
+	}
+	if identicalBytes == false {
+		t.Fatalf("The filter's symmetric key hash was not properly generated by Install")
+	}
+}
+
 func TestComparePubKey(t *testing.T) {
 	InitSingleTest()