whisper: remove linter warnings (#15972)

* whisper: fixes warnings from the code linter

* whisper: more non-API-breaking changes

The remaining lint errors are because of auto-generated
files and one is because an exported function has a non-
exported return type. Changing this would break the API,
and will be part of another commit for easier reversal.

* whisper: un-export NewSentMessage to please the linter

This is an API change, which is why it's in its own commit.
This change was initiated after the linter complained that
the returned type wasn't exported. I chose to un-export
the function instead of exporting the type, because that
type is an implementation detail that I would like to
change in the near future to make the code more
readable and with an increased coverage.

* whisper: update gencodec output after upgrading it to new lint standards

19 files changed, 363 insertions, 328 deletions

diff --git a/cmd/wnode/main.go b/cmd/wnode/main.go
index 05e6b2908..e69b57d69 100644
--- a/cmd/wnode/main.go
+++ b/cmd/wnode/main.go
@@ -601,7 +601,7 @@ func requestExpiredMessagesLoop() {
 	if err != nil {
 		utils.Fatalf("Failed to save symmetric key for mail request: %s", err)
 	}
-	peerID = extractIdFromEnode(*argEnode)
+	peerID = extractIDFromEnode(*argEnode)
 	shh.AllowP2PMessagesFromPeer(peerID)
 
 	for {
@@ -652,7 +652,7 @@ func requestExpiredMessagesLoop() {
 	}
 }
 
-func extractIdFromEnode(s string) []byte {
+func extractIDFromEnode(s string) []byte {
 	n, err := discover.ParseNode(s)
 	if err != nil {
 		utils.Fatalf("Failed to parse enode: %s", err)
diff --git a/whisper/whisperv6/api.go b/whisper/whisperv6/api.go
index 2f6f671e9..6cbce26f0 100644
--- a/whisper/whisperv6/api.go
+++ b/whisper/whisperv6/api.go
@@ -36,6 +36,7 @@ const (
 	filterTimeout = 300 // filters are considered timeout out after filterTimeout seconds
 )
 
+// List of errors
 var (
 	ErrSymAsym              = errors.New("specify either a symmetric or an asymmetric key")
 	ErrInvalidSymmetricKey  = errors.New("invalid symmetric key")
@@ -116,7 +117,7 @@ func (api *PublicWhisperAPI) SetMaxMessageSize(ctx context.Context, size uint32)
 	return true, api.w.SetMaxMessageSize(size)
 }
 
-// SetMinPow sets the minimum PoW, and notifies the peers.
+// SetMinPoW sets the minimum PoW, and notifies the peers.
 func (api *PublicWhisperAPI) SetMinPoW(ctx context.Context, pow float64) (bool, error) {
 	return true, api.w.SetMinimumPoW(pow)
 }
@@ -174,7 +175,7 @@ func (api *PublicWhisperAPI) GetPublicKey(ctx context.Context, id string) (hexut
 	return crypto.FromECDSAPub(&key.PublicKey), nil
 }
 
-// GetPublicKey returns the private key associated with the given key. The key is the hex
+// GetPrivateKey returns the private key associated with the given key. The key is the hex
 // encoded representation of a key in the form specified in section 4.3.6 of ANSI X9.62.
 func (api *PublicWhisperAPI) GetPrivateKey(ctx context.Context, id string) (hexutil.Bytes, error) {
 	key, err := api.w.GetPrivateKey(id)
@@ -291,7 +292,7 @@ func (api *PublicWhisperAPI) Post(ctx context.Context, req NewMessage) (bool, er
 	}
 
 	// encrypt and sent message
-	whisperMsg, err := NewSentMessage(params)
+	whisperMsg, err := newSentMessage(params)
 	if err != nil {
 		return false, err
 	}
diff --git a/whisper/whisperv6/benchmarks_test.go b/whisper/whisperv6/benchmarks_test.go
index 0473179da..52c8f95ea 100644
--- a/whisper/whisperv6/benchmarks_test.go
+++ b/whisper/whisperv6/benchmarks_test.go
@@ -39,7 +39,7 @@ func BenchmarkEncryptionSym(b *testing.B) {
 	}
 
 	for i := 0; i < b.N; i++ {
-		msg, _ := NewSentMessage(params)
+		msg, _ := newSentMessage(params)
 		_, err := msg.Wrap(params)
 		if err != nil {
 			b.Errorf("failed Wrap with seed %d: %s.", seed, err)
@@ -64,7 +64,7 @@ func BenchmarkEncryptionAsym(b *testing.B) {
 	params.Dst = &key.PublicKey
 
 	for i := 0; i < b.N; i++ {
-		msg, _ := NewSentMessage(params)
+		msg, _ := newSentMessage(params)
 		_, err := msg.Wrap(params)
 		if err != nil {
 			b.Fatalf("failed Wrap with seed %d: %s.", seed, err)
@@ -79,7 +79,7 @@ func BenchmarkDecryptionSymValid(b *testing.B) {
 	if err != nil {
 		b.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, _ := NewSentMessage(params)
+	msg, _ := newSentMessage(params)
 	env, err := msg.Wrap(params)
 	if err != nil {
 		b.Fatalf("failed Wrap with seed %d: %s.", seed, err)
@@ -101,7 +101,7 @@ func BenchmarkDecryptionSymInvalid(b *testing.B) {
 	if err != nil {
 		b.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, _ := NewSentMessage(params)
+	msg, _ := newSentMessage(params)
 	env, err := msg.Wrap(params)
 	if err != nil {
 		b.Fatalf("failed Wrap with seed %d: %s.", seed, err)
@@ -130,7 +130,7 @@ func BenchmarkDecryptionAsymValid(b *testing.B) {
 	f := Filter{KeyAsym: key}
 	params.KeySym = nil
 	params.Dst = &key.PublicKey
-	msg, _ := NewSentMessage(params)
+	msg, _ := newSentMessage(params)
 	env, err := msg.Wrap(params)
 	if err != nil {
 		b.Fatalf("failed Wrap with seed %d: %s.", seed, err)
@@ -157,7 +157,7 @@ func BenchmarkDecryptionAsymInvalid(b *testing.B) {
 	}
 	params.KeySym = nil
 	params.Dst = &key.PublicKey
-	msg, _ := NewSentMessage(params)
+	msg, _ := newSentMessage(params)
 	env, err := msg.Wrap(params)
 	if err != nil {
 		b.Fatalf("failed Wrap with seed %d: %s.", seed, err)
@@ -199,7 +199,7 @@ func BenchmarkPoW(b *testing.B) {
 
 	for i := 0; i < b.N; i++ {
 		increment(params.Payload)
-		msg, _ := NewSentMessage(params)
+		msg, _ := newSentMessage(params)
 		_, err := msg.Wrap(params)
 		if err != nil {
 			b.Fatalf("failed Wrap with seed %d: %s.", seed, err)
diff --git a/whisper/whisperv6/config.go b/whisper/whisperv6/config.go
index d7f817aa2..61419de00 100644
--- a/whisper/whisperv6/config.go
+++ b/whisper/whisperv6/config.go
@@ -16,11 +16,13 @@
 
 package whisperv6
 
+// Config represents the configuration state of a whisper node.
 type Config struct {
 	MaxMessageSize     uint32  `toml:",omitempty"`
 	MinimumAcceptedPOW float64 `toml:",omitempty"`
 }
 
+// DefaultConfig represents (shocker!) the default configuration.
 var DefaultConfig = Config{
 	MaxMessageSize:     DefaultMaxMessageSize,
 	MinimumAcceptedPOW: DefaultMinimumPoW,
diff --git a/whisper/whisperv6/doc.go b/whisper/whisperv6/doc.go
index da1b4ee5b..699fd5c76 100644
--- a/whisper/whisperv6/doc.go
+++ b/whisper/whisperv6/doc.go
@@ -27,6 +27,9 @@ Whisper is a pure identity-based messaging system. Whisper provides a low-level
 or prejudiced by the low-level hardware attributes and characteristics,
 particularly the notion of singular endpoints.
 */
+
+// Contains the Whisper protocol constant definitions
+
 package whisperv6
 
 import (
@@ -34,10 +37,11 @@ import (
 	"time"
 )
 
+// Whisper protocol parameters
 const (
-	ProtocolVersion    = uint64(6)
-	ProtocolVersionStr = "6.0"
-	ProtocolName       = "shh"
+	ProtocolVersion    = uint64(6) // Protocol version number
+	ProtocolVersionStr = "6.0"     // The same, as a string
+	ProtocolName       = "shh"     // Nickname of the protocol in geth
 
 	// whisper protocol message codes, according to EIP-627
 	statusCode           = 0   // used by whisper protocol
@@ -55,7 +59,7 @@ const (
 	signatureLength = 65 // in bytes
 	aesKeyLength    = 32 // in bytes
 	AESNonceLength  = 12 // in bytes
-	keyIdSize       = 32 // in bytes
+	keyIDSize       = 32 // in bytes
 	bloomFilterSize = 64 // in bytes
 
 	EnvelopeHeaderLength = 20
diff --git a/whisper/whisperv6/envelope.go b/whisper/whisperv6/envelope.go
index 9ed712b93..6bc1f2c6b 100644
--- a/whisper/whisperv6/envelope.go
+++ b/whisper/whisperv6/envelope.go
@@ -115,6 +115,8 @@ func (e *Envelope) Seal(options *MessageParams) error {
 	return nil
 }
 
+// PoW computes (if necessary) and returns the proof of work target
+// of the envelope.
 func (e *Envelope) PoW() float64 {
 	if e.pow == 0 {
 		e.calculatePoW(0)
diff --git a/whisper/whisperv6/envelope_test.go b/whisper/whisperv6/envelope_test.go
index 410b250a3..1ee1bec41 100644
--- a/whisper/whisperv6/envelope_test.go
+++ b/whisper/whisperv6/envelope_test.go
@@ -45,7 +45,7 @@ func TestEnvelopeOpenAcceptsOnlyOneKeyTypeInFilter(t *testing.T) {
 
 	mrand.Read(params.Payload)
 
-	msg, err := NewSentMessage(&params)
+	msg, err := newSentMessage(&params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
diff --git a/whisper/whisperv6/filter.go b/whisper/whisperv6/filter.go
index a752c7ac9..eb0c65fa3 100644
--- a/whisper/whisperv6/filter.go
+++ b/whisper/whisperv6/filter.go
@@ -26,6 +26,7 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 )
 
+// Filter represents a Whisper message filter
 type Filter struct {
 	Src        *ecdsa.PublicKey  // Sender of the message
 	KeyAsym    *ecdsa.PrivateKey // Private Key of recipient
@@ -39,12 +40,14 @@ type Filter struct {
 	mutex    sync.RWMutex
 }
 
+// Filters represents a collection of filters
 type Filters struct {
 	watchers map[string]*Filter
 	whisper  *Whisper
 	mutex    sync.RWMutex
 }
 
+// NewFilters returns a newly created filter collection
 func NewFilters(w *Whisper) *Filters {
 	return &Filters{
 		watchers: make(map[string]*Filter),
@@ -52,6 +55,7 @@ func NewFilters(w *Whisper) *Filters {
 	}
 }
 
+// Install will add a new filter to the filter collection
 func (fs *Filters) Install(watcher *Filter) (string, error) {
 	if watcher.KeySym != nil && watcher.KeyAsym != nil {
 		return "", fmt.Errorf("filters must choose between symmetric and asymmetric keys")
@@ -81,6 +85,8 @@ func (fs *Filters) Install(watcher *Filter) (string, error) {
 	return id, err
 }
 
+// Uninstall will remove a filter whose id has been specified from
+// the filter collection
 func (fs *Filters) Uninstall(id string) bool {
 	fs.mutex.Lock()
 	defer fs.mutex.Unlock()
@@ -91,12 +97,15 @@ func (fs *Filters) Uninstall(id string) bool {
 	return false
 }
 
+// Get returns a filter from the collection with a specific ID
 func (fs *Filters) Get(id string) *Filter {
 	fs.mutex.RLock()
 	defer fs.mutex.RUnlock()
 	return fs.watchers[id]
 }
 
+// NotifyWatchers notifies any filter that has declared interest
+// for the envelope's topic.
 func (fs *Filters) NotifyWatchers(env *Envelope, p2pMessage bool) {
 	var msg *ReceivedMessage
 
@@ -140,9 +149,9 @@ func (f *Filter) processEnvelope(env *Envelope) *ReceivedMessage {
 		msg := env.Open(f)
 		if msg != nil {
 			return msg
-		} else {
-			log.Trace("processing envelope: failed to open", "hash", env.Hash().Hex())
 		}
+
+		log.Trace("processing envelope: failed to open", "hash", env.Hash().Hex())
 	} else {
 		log.Trace("processing envelope: does not match", "hash", env.Hash().Hex())
 	}
@@ -157,6 +166,8 @@ func (f *Filter) expectsSymmetricEncryption() bool {
 	return f.KeySym != nil
 }
 
+// Trigger adds a yet-unknown message to the filter's list of
+// received messages.
 func (f *Filter) Trigger(msg *ReceivedMessage) {
 	f.mutex.Lock()
 	defer f.mutex.Unlock()
@@ -166,6 +177,8 @@ func (f *Filter) Trigger(msg *ReceivedMessage) {
 	}
 }
 
+// Retrieve will return the list of all received messages associated
+// to a filter.
 func (f *Filter) Retrieve() (all []*ReceivedMessage) {
 	f.mutex.Lock()
 	defer f.mutex.Unlock()
@@ -195,7 +208,7 @@ func (f *Filter) MatchMessage(msg *ReceivedMessage) bool {
 	return false
 }
 
-// MatchEvelope checks if it's worth decrypting the message. If
+// MatchEnvelope checks if it's worth decrypting the message. If
 // it returns `true`, client code is expected to attempt decrypting
 // the message and subsequently call MatchMessage.
 func (f *Filter) MatchEnvelope(envelope *Envelope) bool {
@@ -206,6 +219,7 @@ func (f *Filter) MatchEnvelope(envelope *Envelope) bool {
 	return f.MatchTopic(envelope.Topic)
 }
 
+// MatchTopic checks that the filter captures a given topic.
 func (f *Filter) MatchTopic(topic TopicType) bool {
 	if len(f.Topics) == 0 {
 		// any topic matches
@@ -237,6 +251,7 @@ func matchSingleTopic(topic TopicType, bt []byte) bool {
 	return true
 }
 
+// IsPubKeyEqual checks that two public keys are equal
 func IsPubKeyEqual(a, b *ecdsa.PublicKey) bool {
 	if !ValidatePublicKey(a) {
 		return false
diff --git a/whisper/whisperv6/filter_test.go b/whisper/whisperv6/filter_test.go
index 9c7fdad95..fc7db7671 100644
--- a/whisper/whisperv6/filter_test.go
+++ b/whisper/whisperv6/filter_test.go
@@ -109,7 +109,7 @@ func TestInstallFilters(t *testing.T) {
 			t.Fatalf("seed %d: failed to install filter: %s", seed, err)
 		}
 		tst[i].id = j
-		if len(j) != keyIdSize*2 {
+		if len(j) != keyIDSize*2 {
 			t.Fatalf("seed %d: wrong filter id size [%d]", seed, len(j))
 		}
 	}
@@ -199,7 +199,7 @@ func TestInstallIdenticalFilters(t *testing.T) {
 	filter1.Src = &params.Src.PublicKey
 	filter2.Src = &params.Src.PublicKey
 
-	sentMessage, err := NewSentMessage(params)
+	sentMessage, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -306,7 +306,7 @@ func TestMatchEnvelope(t *testing.T) {
 	params.Topic[0] = 0xFF // ensure mismatch
 
 	// mismatch with pseudo-random data
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -327,7 +327,7 @@ func TestMatchEnvelope(t *testing.T) {
 	i := mrand.Int() % 4
 	fsym.Topics[i] = params.Topic[:]
 	fasym.Topics[i] = params.Topic[:]
-	msg, err = NewSentMessage(params)
+	msg, err = newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -372,7 +372,7 @@ func TestMatchEnvelope(t *testing.T) {
 	}
 	params.KeySym = nil
 	params.Dst = &key.PublicKey
-	msg, err = NewSentMessage(params)
+	msg, err = newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -453,7 +453,7 @@ func TestMatchMessageSym(t *testing.T) {
 	params.KeySym = f.KeySym
 	params.Topic = BytesToTopic(f.Topics[index])
 
-	sentMessage, err := NewSentMessage(params)
+	sentMessage, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -546,7 +546,7 @@ func TestMatchMessageAsym(t *testing.T) {
 	keySymOrig := params.KeySym
 	params.KeySym = nil
 
-	sentMessage, err := NewSentMessage(params)
+	sentMessage, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -630,7 +630,7 @@ func generateCompatibeEnvelope(t *testing.T, f *Filter) *Envelope {
 
 	params.KeySym = f.KeySym
 	params.Topic = BytesToTopic(f.Topics[2])
-	sentMessage, err := NewSentMessage(params)
+	sentMessage, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -806,7 +806,7 @@ func TestVariableTopics(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
diff --git a/whisper/whisperv6/gen_criteria_json.go b/whisper/whisperv6/gen_criteria_json.go
index a298396cc..1a428d6df 100644
--- a/whisper/whisperv6/gen_criteria_json.go
+++ b/whisper/whisperv6/gen_criteria_json.go
@@ -10,6 +10,7 @@ import (
 
 var _ = (*criteriaOverride)(nil)
 
+// MarshalJSON marshals type Criteria to a json string
 func (c Criteria) MarshalJSON() ([]byte, error) {
 	type Criteria struct {
 		SymKeyID     string        `json:"symKeyID"`
@@ -29,6 +30,7 @@ func (c Criteria) MarshalJSON() ([]byte, error) {
 	return json.Marshal(&enc)
 }
 
+// UnmarshalJSON unmarshals type Criteria to a json string
 func (c *Criteria) UnmarshalJSON(input []byte) error {
 	type Criteria struct {
 		SymKeyID     *string        `json:"symKeyID"`
diff --git a/whisper/whisperv6/gen_message_json.go b/whisper/whisperv6/gen_message_json.go
index e193ba3e2..6218f5df6 100644
--- a/whisper/whisperv6/gen_message_json.go
+++ b/whisper/whisperv6/gen_message_json.go
@@ -10,6 +10,7 @@ import (
 
 var _ = (*messageOverride)(nil)
 
+// MarshalJSON marshals type Message to a json string
 func (m Message) MarshalJSON() ([]byte, error) {
 	type Message struct {
 		Sig       hexutil.Bytes `json:"sig,omitempty"`
@@ -35,6 +36,7 @@ func (m Message) MarshalJSON() ([]byte, error) {
 	return json.Marshal(&enc)
 }
 
+// UnmarshalJSON unmarshals type Message to a json string
 func (m *Message) UnmarshalJSON(input []byte) error {
 	type Message struct {
 		Sig       *hexutil.Bytes `json:"sig,omitempty"`
diff --git a/whisper/whisperv6/gen_newmessage_json.go b/whisper/whisperv6/gen_newmessage_json.go
index 6250579f4..75a1279ae 100644
--- a/whisper/whisperv6/gen_newmessage_json.go
+++ b/whisper/whisperv6/gen_newmessage_json.go
@@ -10,6 +10,7 @@ import (
 
 var _ = (*newMessageOverride)(nil)
 
+// MarshalJSON marshals type NewMessage to a json string
 func (n NewMessage) MarshalJSON() ([]byte, error) {
 	type NewMessage struct {
 		SymKeyID   string        `json:"symKeyID"`
@@ -37,6 +38,7 @@ func (n NewMessage) MarshalJSON() ([]byte, error) {
 	return json.Marshal(&enc)
 }
 
+// UnmarshalJSON unmarshals type NewMessage to a json string
 func (n *NewMessage) UnmarshalJSON(input []byte) error {
 	type NewMessage struct {
 		SymKeyID   *string        `json:"symKeyID"`
diff --git a/whisper/whisperv6/message.go b/whisper/whisperv6/message.go
index f8df50336..b5c8279b1 100644
--- a/whisper/whisperv6/message.go
+++ b/whisper/whisperv6/message.go
@@ -33,7 +33,8 @@ import (
 	"github.com/ethereum/go-ethereum/log"
 )
 
-// Options specifies the exact way a message should be wrapped into an Envelope.
+// MessageParams specifies the exact way a message should be wrapped
+// into an Envelope.
 type MessageParams struct {
 	TTL      uint32
 	Src      *ecdsa.PrivateKey
@@ -86,8 +87,8 @@ func (msg *ReceivedMessage) isAsymmetricEncryption() bool {
 	return msg.Dst != nil
 }
 
-// NewMessage creates and initializes a non-signed, non-encrypted Whisper message.
-func NewSentMessage(params *MessageParams) (*sentMessage, error) {
+// NewSentMessage creates and initializes a non-signed, non-encrypted Whisper message.
+func newSentMessage(params *MessageParams) (*sentMessage, error) {
 	msg := sentMessage{}
 	msg.Raw = make([]byte, 1, len(params.Payload)+len(params.Padding)+signatureLength+padSizeLimit)
 	msg.Raw[0] = 0 // set all the flags to zero
@@ -341,7 +342,8 @@ func (msg *ReceivedMessage) extractPadding(end int) (int, bool) {
 	return paddingSize, true
 }
 
-// Recover retrieves the public key of the message signer.
+// SigToPubKey returns the public key associated to the message's
+// signature.
 func (msg *ReceivedMessage) SigToPubKey() *ecdsa.PublicKey {
 	defer func() { recover() }() // in case of invalid signature
 
diff --git a/whisper/whisperv6/message_test.go b/whisper/whisperv6/message_test.go
index c90bcc01e..5f8b41edc 100644
--- a/whisper/whisperv6/message_test.go
+++ b/whisper/whisperv6/message_test.go
@@ -70,7 +70,7 @@ func singleMessageTest(t *testing.T, symmetric bool) {
 	text := make([]byte, 0, 512)
 	text = append(text, params.Payload...)
 
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -128,7 +128,7 @@ func TestMessageWrap(t *testing.T) {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
 
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -146,7 +146,7 @@ func TestMessageWrap(t *testing.T) {
 	}
 
 	// set PoW target too high, expect error
-	msg2, err := NewSentMessage(params)
+	msg2, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -169,7 +169,7 @@ func TestMessageSeal(t *testing.T) {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
 
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -231,7 +231,7 @@ func singleEnvelopeOpenTest(t *testing.T, symmetric bool) {
 	text := make([]byte, 0, 512)
 	text = append(text, params.Payload...)
 
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -286,7 +286,7 @@ func TestEncryptWithZeroKey(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -300,7 +300,7 @@ func TestEncryptWithZeroKey(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, err = NewSentMessage(params)
+	msg, err = newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -314,7 +314,7 @@ func TestEncryptWithZeroKey(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, err = NewSentMessage(params)
+	msg, err = newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -332,7 +332,7 @@ func TestRlpEncode(t *testing.T) {
 	if err != nil {
 		t.Fatalf("failed generateMessageParams with seed %d: %s.", seed, err)
 	}
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -376,7 +376,7 @@ func singlePaddingTest(t *testing.T, padSize int) {
 	if n != padSize {
 		t.Fatalf("padding is not copied (seed %d): %s", seed, err)
 	}
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
diff --git a/whisper/whisperv6/peer.go b/whisper/whisperv6/peer.go
index 08071c0f7..4f9a7c378 100644
--- a/whisper/whisperv6/peer.go
+++ b/whisper/whisperv6/peer.go
@@ -28,7 +28,7 @@ import (
 	set "gopkg.in/fatih/set.v0"
 )
 
-// peer represents a whisper protocol peer connection.
+// Peer represents a whisper protocol peer connection.
 type Peer struct {
 	host *Whisper
 	peer *p2p.Peer
@@ -58,48 +58,48 @@ func newPeer(host *Whisper, remote *p2p.Peer, rw p2p.MsgReadWriter) *Peer {
 
 // start initiates the peer updater, periodically broadcasting the whisper packets
 // into the network.
-func (p *Peer) start() {
-	go p.update()
-	log.Trace("start", "peer", p.ID())
+func (peer *Peer) start() {
+	go peer.update()
+	log.Trace("start", "peer", peer.ID())
 }
 
 // stop terminates the peer updater, stopping message forwarding to it.
-func (p *Peer) stop() {
-	close(p.quit)
-	log.Trace("stop", "peer", p.ID())
+func (peer *Peer) stop() {
+	close(peer.quit)
+	log.Trace("stop", "peer", peer.ID())
 }
 
 // handshake sends the protocol initiation status message to the remote peer and
 // verifies the remote status too.
-func (p *Peer) handshake() error {
+func (peer *Peer) handshake() error {
 	// Send the handshake status message asynchronously
 	errc := make(chan error, 1)
 	go func() {
-		pow := p.host.MinPow()
+		pow := peer.host.MinPow()
 		powConverted := math.Float64bits(pow)
-		bloom := p.host.BloomFilter()
-		errc <- p2p.SendItems(p.ws, statusCode, ProtocolVersion, powConverted, bloom)
+		bloom := peer.host.BloomFilter()
+		errc <- p2p.SendItems(peer.ws, statusCode, ProtocolVersion, powConverted, bloom)
 	}()
 
 	// Fetch the remote status packet and verify protocol match
-	packet, err := p.ws.ReadMsg()
+	packet, err := peer.ws.ReadMsg()
 	if err != nil {
 		return err
 	}
 	if packet.Code != statusCode {
-		return fmt.Errorf("peer [%x] sent packet %x before status packet", p.ID(), packet.Code)
+		return fmt.Errorf("peer [%x] sent packet %x before status packet", peer.ID(), packet.Code)
 	}
 	s := rlp.NewStream(packet.Payload, uint64(packet.Size))
 	_, err = s.List()
 	if err != nil {
-		return fmt.Errorf("peer [%x] sent bad status message: %v", p.ID(), err)
+		return fmt.Errorf("peer [%x] sent bad status message: %v", peer.ID(), err)
 	}
 	peerVersion, err := s.Uint()
 	if err != nil {
-		return fmt.Errorf("peer [%x] sent bad status message (unable to decode version): %v", p.ID(), err)
+		return fmt.Errorf("peer [%x] sent bad status message (unable to decode version): %v", peer.ID(), err)
 	}
 	if peerVersion != ProtocolVersion {
-		return fmt.Errorf("peer [%x]: protocol version mismatch %d != %d", p.ID(), peerVersion, ProtocolVersion)
+		return fmt.Errorf("peer [%x]: protocol version mismatch %d != %d", peer.ID(), peerVersion, ProtocolVersion)
 	}
 
 	// only version is mandatory, subsequent parameters are optional
@@ -107,34 +107,34 @@ func (p *Peer) handshake() error {
 	if err == nil {
 		pow := math.Float64frombits(powRaw)
 		if math.IsInf(pow, 0) || math.IsNaN(pow) || pow < 0.0 {
-			return fmt.Errorf("peer [%x] sent bad status message: invalid pow", p.ID())
+			return fmt.Errorf("peer [%x] sent bad status message: invalid pow", peer.ID())
 		}
-		p.powRequirement = pow
+		peer.powRequirement = pow
 
 		var bloom []byte
 		err = s.Decode(&bloom)
 		if err == nil {
 			sz := len(bloom)
 			if sz != bloomFilterSize && sz != 0 {
-				return fmt.Errorf("peer [%x] sent bad status message: wrong bloom filter size %d", p.ID(), sz)
+				return fmt.Errorf("peer [%x] sent bad status message: wrong bloom filter size %d", peer.ID(), sz)
 			}
 			if isFullNode(bloom) {
-				p.bloomFilter = nil
+				peer.bloomFilter = nil
 			} else {
-				p.bloomFilter = bloom
+				peer.bloomFilter = bloom
 			}
 		}
 	}
 
 	if err := <-errc; err != nil {
-		return fmt.Errorf("peer [%x] failed to send status packet: %v", p.ID(), err)
+		return fmt.Errorf("peer [%x] failed to send status packet: %v", peer.ID(), err)
 	}
 	return nil
 }
 
 // update executes periodic operations on the peer, including message transmission
 // and expiration.
-func (p *Peer) update() {
+func (peer *Peer) update() {
 	// Start the tickers for the updates
 	expire := time.NewTicker(expirationCycle)
 	transmit := time.NewTicker(transmissionCycle)
@@ -143,15 +143,15 @@ func (p *Peer) update() {
 	for {
 		select {
 		case <-expire.C:
-			p.expire()
+			peer.expire()
 
 		case <-transmit.C:
-			if err := p.broadcast(); err != nil {
-				log.Trace("broadcast failed", "reason", err, "peer", p.ID())
+			if err := peer.broadcast(); err != nil {
+				log.Trace("broadcast failed", "reason", err, "peer", peer.ID())
 				return
 			}
 
-		case <-p.quit:
+		case <-peer.quit:
 			return
 		}
 	}
@@ -185,24 +185,24 @@ func (peer *Peer) expire() {
 
 // broadcast iterates over the collection of envelopes and transmits yet unknown
 // ones over the network.
-func (p *Peer) broadcast() error {
-	envelopes := p.host.Envelopes()
+func (peer *Peer) broadcast() error {
+	envelopes := peer.host.Envelopes()
 	bundle := make([]*Envelope, 0, len(envelopes))
 	for _, envelope := range envelopes {
-		if !p.marked(envelope) && envelope.PoW() >= p.powRequirement && p.bloomMatch(envelope) {
+		if !peer.marked(envelope) && envelope.PoW() >= peer.powRequirement && peer.bloomMatch(envelope) {
 			bundle = append(bundle, envelope)
 		}
 	}
 
 	if len(bundle) > 0 {
 		// transmit the batch of envelopes
-		if err := p2p.Send(p.ws, messagesCode, bundle); err != nil {
+		if err := p2p.Send(peer.ws, messagesCode, bundle); err != nil {
 			return err
 		}
 
 		// mark envelopes only if they were successfully sent
 		for _, e := range bundle {
-			p.mark(e)
+			peer.mark(e)
 		}
 
 		log.Trace("broadcast", "num. messages", len(bundle))
@@ -210,25 +210,26 @@ func (p *Peer) broadcast() error {
 	return nil
 }
 
-func (p *Peer) ID() []byte {
-	id := p.peer.ID()
+// ID returns a peer's id
+func (peer *Peer) ID() []byte {
+	id := peer.peer.ID()
 	return id[:]
 }
 
-func (p *Peer) notifyAboutPowRequirementChange(pow float64) error {
+func (peer *Peer) notifyAboutPowRequirementChange(pow float64) error {
 	i := math.Float64bits(pow)
-	return p2p.Send(p.ws, powRequirementCode, i)
+	return p2p.Send(peer.ws, powRequirementCode, i)
 }
 
-func (p *Peer) notifyAboutBloomFilterChange(bloom []byte) error {
-	return p2p.Send(p.ws, bloomFilterExCode, bloom)
+func (peer *Peer) notifyAboutBloomFilterChange(bloom []byte) error {
+	return p2p.Send(peer.ws, bloomFilterExCode, bloom)
 }
 
-func (p *Peer) bloomMatch(env *Envelope) bool {
-	if p.bloomFilter == nil {
+func (peer *Peer) bloomMatch(env *Envelope) bool {
+	if peer.bloomFilter == nil {
 		// no filter - full node, accepts all envelops
 		return true
 	}
 
-	return bloomFilterMatch(p.bloomFilter, env.Bloom())
+	return bloomFilterMatch(peer.bloomFilter, env.Bloom())
 }
diff --git a/whisper/whisperv6/peer_test.go b/whisper/whisperv6/peer_test.go
index 8a65cb714..b0709c927 100644
--- a/whisper/whisperv6/peer_test.go
+++ b/whisper/whisperv6/peer_test.go
@@ -33,7 +33,7 @@ import (
 	"github.com/ethereum/go-ethereum/p2p/nat"
 )
 
-var keys []string = []string{
+var keys = []string{
 	"d49dcf37238dc8a7aac57dc61b9fee68f0a97f062968978b9fafa7d1033d03a9",
 	"73fd6143c48e80ed3c56ea159fe7494a0b6b393a392227b422f4c3e8f1b54f98",
 	"119dd32adb1daa7a4c7bf77f847fb28730785aa92947edf42fdd997b54de40dc",
@@ -80,17 +80,17 @@ type TestNode struct {
 	shh     *Whisper
 	id      *ecdsa.PrivateKey
 	server  *p2p.Server
-	filerId string
+	filerID string
 }
 
 var result TestData
 var nodes [NumNodes]*TestNode
-var sharedKey []byte = []byte("some arbitrary data here")
-var sharedTopic TopicType = TopicType{0xF, 0x1, 0x2, 0}
-var expectedMessage []byte = []byte("per rectum ad astra")
+var sharedKey = []byte("some arbitrary data here")
+var sharedTopic = TopicType{0xF, 0x1, 0x2, 0}
+var expectedMessage = []byte("per rectum ad astra")
 var masterBloomFilter []byte
 var masterPow = 0.00000001
-var round int = 1
+var round = 1
 
 func TestSimulation(t *testing.T) {
 	// create a chain of whisper nodes,
@@ -186,7 +186,7 @@ func initialize(t *testing.T) {
 		topics = append(topics, sharedTopic)
 		f := Filter{KeySym: sharedKey}
 		f.Topics = [][]byte{topics[0][:]}
-		node.filerId, err = node.shh.Subscribe(&f)
+		node.filerID, err = node.shh.Subscribe(&f)
 		if err != nil {
 			t.Fatalf("failed to install the filter: %s.", err)
 		}
@@ -199,9 +199,9 @@ func initialize(t *testing.T) {
 		name := common.MakeName("whisper-go", "2.0")
 		var peers []*discover.Node
 		if i > 0 {
-			peerNodeId := nodes[i-1].id
+			peerNodeID := nodes[i-1].id
 			peerPort := uint16(port - 1)
-			peerNode := discover.PubkeyID(&peerNodeId.PublicKey)
+			peerNode := discover.PubkeyID(&peerNodeID.PublicKey)
 			peer := discover.NewNode(peerNode, ip, peerPort, peerPort)
 			peers = append(peers, peer)
 		}
@@ -238,7 +238,7 @@ func stopServers() {
 	for i := 0; i < NumNodes; i++ {
 		n := nodes[i]
 		if n != nil {
-			n.shh.Unsubscribe(n.filerId)
+			n.shh.Unsubscribe(n.filerID)
 			n.shh.Stop()
 			n.server.Stop()
 		}
@@ -260,9 +260,9 @@ func checkPropagation(t *testing.T, includingNodeZero bool) {
 
 	for j := 0; j < iterations; j++ {
 		for i := first; i < NumNodes; i++ {
-			f := nodes[i].shh.GetFilter(nodes[i].filerId)
+			f := nodes[i].shh.GetFilter(nodes[i].filerID)
 			if f == nil {
-				t.Fatalf("failed to get filterId %s from node %d, round %d.", nodes[i].filerId, i, round)
+				t.Fatalf("failed to get filterId %s from node %d, round %d.", nodes[i].filerID, i, round)
 			}
 
 			mail := f.Retrieve()
@@ -281,7 +281,7 @@ func checkPropagation(t *testing.T, includingNodeZero bool) {
 	t.Fatalf("Test was not complete: timeout %d seconds.", iterations*cycle/1000)
 
 	if !includingNodeZero {
-		f := nodes[0].shh.GetFilter(nodes[0].filerId)
+		f := nodes[0].shh.GetFilter(nodes[0].filerID)
 		if f != nil {
 			t.Fatalf("node zero received a message with low PoW.")
 		}
@@ -348,7 +348,7 @@ func sendMsg(t *testing.T, expected bool, id int) {
 		opt.Payload = opt.Payload[1:]
 	}
 
-	msg, err := NewSentMessage(&opt)
+	msg, err := newSentMessage(&opt)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -372,7 +372,7 @@ func TestPeerBasic(t *testing.T) {
 	}
 
 	params.PoW = 0.001
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
diff --git a/whisper/whisperv6/topic.go b/whisper/whisperv6/topic.go
index bf5da01e3..4dd8f283c 100644
--- a/whisper/whisperv6/topic.go
+++ b/whisper/whisperv6/topic.go
@@ -23,11 +23,13 @@ import (
 	"github.com/ethereum/go-ethereum/common/hexutil"
 )
 
-// Topic represents a cryptographically secure, probabilistic partial
+// TopicType represents a cryptographically secure, probabilistic partial
 // classifications of a message, determined as the first (left) 4 bytes of the
 // SHA3 hash of some arbitrary data given by the original author of the message.
 type TopicType [TopicLength]byte
 
+// BytesToTopic converts from the byte array representation of a topic
+// into the TopicType type.
 func BytesToTopic(b []byte) (t TopicType) {
 	sz := TopicLength
 	if x := len(b); x < TopicLength {
diff --git a/whisper/whisperv6/whisper.go b/whisper/whisperv6/whisper.go
index bc89aadcc..1b440a7f9 100644
--- a/whisper/whisperv6/whisper.go
+++ b/whisper/whisperv6/whisper.go
@@ -39,6 +39,8 @@ import (
 	set "gopkg.in/fatih/set.v0"
 )
 
+// Statistics holds several message-related counter for analytics
+// purposes.
 type Statistics struct {
 	messagesCleared      int
 	memoryCleared        int
@@ -130,8 +132,8 @@ func New(cfg *Config) *Whisper {
 }
 
 // MinPow returns the PoW value required by this node.
-func (w *Whisper) MinPow() float64 {
-	val, exist := w.settings.Load(minPowIdx)
+func (whisper *Whisper) MinPow() float64 {
+	val, exist := whisper.settings.Load(minPowIdx)
 	if !exist || val == nil {
 		return DefaultMinimumPoW
 	}
@@ -146,8 +148,8 @@ func (w *Whisper) MinPow() float64 {
 // MinPowTolerance returns the value of minimum PoW which is tolerated for a limited
 // time after PoW was changed. If sufficient time have elapsed or no change of PoW
 // have ever occurred, the return value will be the same as return value of MinPow().
-func (w *Whisper) MinPowTolerance() float64 {
-	val, exist := w.settings.Load(minPowToleranceIdx)
+func (whisper *Whisper) MinPowTolerance() float64 {
+	val, exist := whisper.settings.Load(minPowToleranceIdx)
 	if !exist || val == nil {
 		return DefaultMinimumPoW
 	}
@@ -158,8 +160,8 @@ func (w *Whisper) MinPowTolerance() float64 {
 // The nodes are required to send only messages that match the advertised bloom filter.
 // If a message does not match the bloom, it will tantamount to spam, and the peer will
 // be disconnected.
-func (w *Whisper) BloomFilter() []byte {
-	val, exist := w.settings.Load(bloomFilterIdx)
+func (whisper *Whisper) BloomFilter() []byte {
+	val, exist := whisper.settings.Load(bloomFilterIdx)
 	if !exist || val == nil {
 		return nil
 	}
@@ -170,8 +172,8 @@ func (w *Whisper) BloomFilter() []byte {
 // time after new bloom was advertised to the peers. If sufficient time have elapsed
 // or no change of bloom filter have ever occurred, the return value will be the same
 // as return value of BloomFilter().
-func (w *Whisper) BloomFilterTolerance() []byte {
-	val, exist := w.settings.Load(bloomFilterToleranceIdx)
+func (whisper *Whisper) BloomFilterTolerance() []byte {
+	val, exist := whisper.settings.Load(bloomFilterToleranceIdx)
 	if !exist || val == nil {
 		return nil
 	}
@@ -179,24 +181,24 @@ func (w *Whisper) BloomFilterTolerance() []byte {
 }
 
 // MaxMessageSize returns the maximum accepted message size.
-func (w *Whisper) MaxMessageSize() uint32 {
-	val, _ := w.settings.Load(maxMsgSizeIdx)
+func (whisper *Whisper) MaxMessageSize() uint32 {
+	val, _ := whisper.settings.Load(maxMsgSizeIdx)
 	return val.(uint32)
 }
 
 // Overflow returns an indication if the message queue is full.
-func (w *Whisper) Overflow() bool {
-	val, _ := w.settings.Load(overflowIdx)
+func (whisper *Whisper) Overflow() bool {
+	val, _ := whisper.settings.Load(overflowIdx)
 	return val.(bool)
 }
 
 // APIs returns the RPC descriptors the Whisper implementation offers
-func (w *Whisper) APIs() []rpc.API {
+func (whisper *Whisper) APIs() []rpc.API {
 	return []rpc.API{
 		{
 			Namespace: ProtocolName,
 			Version:   ProtocolVersionStr,
-			Service:   NewPublicWhisperAPI(w),
+			Service:   NewPublicWhisperAPI(whisper),
 			Public:    true,
 		},
 	}
@@ -204,31 +206,31 @@ func (w *Whisper) APIs() []rpc.API {
 
 // RegisterServer registers MailServer interface.
 // MailServer will process all the incoming messages with p2pRequestCode.
-func (w *Whisper) RegisterServer(server MailServer) {
-	w.mailServer = server
+func (whisper *Whisper) RegisterServer(server MailServer) {
+	whisper.mailServer = server
 }
 
 // Protocols returns the whisper sub-protocols ran by this particular client.
-func (w *Whisper) Protocols() []p2p.Protocol {
-	return []p2p.Protocol{w.protocol}
+func (whisper *Whisper) Protocols() []p2p.Protocol {
+	return []p2p.Protocol{whisper.protocol}
 }
 
 // Version returns the whisper sub-protocols version number.
-func (w *Whisper) Version() uint {
-	return w.protocol.Version
+func (whisper *Whisper) Version() uint {
+	return whisper.protocol.Version
 }
 
 // SetMaxMessageSize sets the maximal message size allowed by this node
-func (w *Whisper) SetMaxMessageSize(size uint32) error {
+func (whisper *Whisper) SetMaxMessageSize(size uint32) error {
 	if size > MaxMessageSize {
 		return fmt.Errorf("message size too large [%d>%d]", size, MaxMessageSize)
 	}
-	w.settings.Store(maxMsgSizeIdx, size)
+	whisper.settings.Store(maxMsgSizeIdx, size)
 	return nil
 }
 
 // SetBloomFilter sets the new bloom filter
-func (w *Whisper) SetBloomFilter(bloom []byte) error {
+func (whisper *Whisper) SetBloomFilter(bloom []byte) error {
 	if len(bloom) != bloomFilterSize {
 		return fmt.Errorf("invalid bloom filter size: %d", len(bloom))
 	}
@@ -236,45 +238,45 @@ func (w *Whisper) SetBloomFilter(bloom []byte) error {
 	b := make([]byte, bloomFilterSize)
 	copy(b, bloom)
 
-	w.settings.Store(bloomFilterIdx, b)
-	w.notifyPeersAboutBloomFilterChange(b)
+	whisper.settings.Store(bloomFilterIdx, b)
+	whisper.notifyPeersAboutBloomFilterChange(b)
 
 	go func() {
 		// allow some time before all the peers have processed the notification
-		time.Sleep(time.Duration(w.syncAllowance) * time.Second)
-		w.settings.Store(bloomFilterToleranceIdx, b)
+		time.Sleep(time.Duration(whisper.syncAllowance) * time.Second)
+		whisper.settings.Store(bloomFilterToleranceIdx, b)
 	}()
 
 	return nil
 }
 
 // SetMinimumPoW sets the minimal PoW required by this node
-func (w *Whisper) SetMinimumPoW(val float64) error {
+func (whisper *Whisper) SetMinimumPoW(val float64) error {
 	if val < 0.0 {
 		return fmt.Errorf("invalid PoW: %f", val)
 	}
 
-	w.settings.Store(minPowIdx, val)
-	w.notifyPeersAboutPowRequirementChange(val)
+	whisper.settings.Store(minPowIdx, val)
+	whisper.notifyPeersAboutPowRequirementChange(val)
 
 	go func() {
 		// allow some time before all the peers have processed the notification
-		time.Sleep(time.Duration(w.syncAllowance) * time.Second)
-		w.settings.Store(minPowToleranceIdx, val)
+		time.Sleep(time.Duration(whisper.syncAllowance) * time.Second)
+		whisper.settings.Store(minPowToleranceIdx, val)
 	}()
 
 	return nil
 }
 
-// SetMinimumPoW sets the minimal PoW in test environment
-func (w *Whisper) SetMinimumPowTest(val float64) {
-	w.settings.Store(minPowIdx, val)
-	w.notifyPeersAboutPowRequirementChange(val)
-	w.settings.Store(minPowToleranceIdx, val)
+// SetMinimumPowTest sets the minimal PoW in test environment
+func (whisper *Whisper) SetMinimumPowTest(val float64) {
+	whisper.settings.Store(minPowIdx, val)
+	whisper.notifyPeersAboutPowRequirementChange(val)
+	whisper.settings.Store(minPowToleranceIdx, val)
 }
 
-func (w *Whisper) notifyPeersAboutPowRequirementChange(pow float64) {
-	arr := w.getPeers()
+func (whisper *Whisper) notifyPeersAboutPowRequirementChange(pow float64) {
+	arr := whisper.getPeers()
 	for _, p := range arr {
 		err := p.notifyAboutPowRequirementChange(pow)
 		if err != nil {
@@ -287,8 +289,8 @@ func (w *Whisper) notifyPeersAboutPowRequirementChange(pow float64) {
 	}
 }
 
-func (w *Whisper) notifyPeersAboutBloomFilterChange(bloom []byte) {
-	arr := w.getPeers()
+func (whisper *Whisper) notifyPeersAboutBloomFilterChange(bloom []byte) {
+	arr := whisper.getPeers()
 	for _, p := range arr {
 		err := p.notifyAboutBloomFilterChange(bloom)
 		if err != nil {
@@ -301,23 +303,23 @@ func (w *Whisper) notifyPeersAboutBloomFilterChange(bloom []byte) {
 	}
 }
 
-func (w *Whisper) getPeers() []*Peer {
-	arr := make([]*Peer, len(w.peers))
+func (whisper *Whisper) getPeers() []*Peer {
+	arr := make([]*Peer, len(whisper.peers))
 	i := 0
-	w.peerMu.Lock()
-	for p := range w.peers {
+	whisper.peerMu.Lock()
+	for p := range whisper.peers {
 		arr[i] = p
 		i++
 	}
-	w.peerMu.Unlock()
+	whisper.peerMu.Unlock()
 	return arr
 }
 
 // getPeer retrieves peer by ID
-func (w *Whisper) getPeer(peerID []byte) (*Peer, error) {
-	w.peerMu.Lock()
-	defer w.peerMu.Unlock()
-	for p := range w.peers {
+func (whisper *Whisper) getPeer(peerID []byte) (*Peer, error) {
+	whisper.peerMu.Lock()
+	defer whisper.peerMu.Unlock()
+	for p := range whisper.peers {
 		id := p.peer.ID()
 		if bytes.Equal(peerID, id[:]) {
 			return p, nil
@@ -328,8 +330,8 @@ func (w *Whisper) getPeer(peerID []byte) (*Peer, error) {
 
 // AllowP2PMessagesFromPeer marks specific peer trusted,
 // which will allow it to send historic (expired) messages.
-func (w *Whisper) AllowP2PMessagesFromPeer(peerID []byte) error {
-	p, err := w.getPeer(peerID)
+func (whisper *Whisper) AllowP2PMessagesFromPeer(peerID []byte) error {
+	p, err := whisper.getPeer(peerID)
 	if err != nil {
 		return err
 	}
@@ -342,8 +344,8 @@ func (w *Whisper) AllowP2PMessagesFromPeer(peerID []byte) error {
 // request and respond with a number of peer-to-peer messages (possibly expired),
 // which are not supposed to be forwarded any further.
 // The whisper protocol is agnostic of the format and contents of envelope.
-func (w *Whisper) RequestHistoricMessages(peerID []byte, envelope *Envelope) error {
-	p, err := w.getPeer(peerID)
+func (whisper *Whisper) RequestHistoricMessages(peerID []byte, envelope *Envelope) error {
+	p, err := whisper.getPeer(peerID)
 	if err != nil {
 		return err
 	}
@@ -352,22 +354,22 @@ func (w *Whisper) RequestHistoricMessages(peerID []byte, envelope *Envelope) err
 }
 
 // SendP2PMessage sends a peer-to-peer message to a specific peer.
-func (w *Whisper) SendP2PMessage(peerID []byte, envelope *Envelope) error {
-	p, err := w.getPeer(peerID)
+func (whisper *Whisper) SendP2PMessage(peerID []byte, envelope *Envelope) error {
+	p, err := whisper.getPeer(peerID)
 	if err != nil {
 		return err
 	}
-	return w.SendP2PDirect(p, envelope)
+	return whisper.SendP2PDirect(p, envelope)
 }
 
 // SendP2PDirect sends a peer-to-peer message to a specific peer.
-func (w *Whisper) SendP2PDirect(peer *Peer, envelope *Envelope) error {
+func (whisper *Whisper) SendP2PDirect(peer *Peer, envelope *Envelope) error {
 	return p2p.Send(peer.ws, p2pMessageCode, envelope)
 }
 
 // NewKeyPair generates a new cryptographic identity for the client, and injects
 // it into the known identities for message decryption. Returns ID of the new key pair.
-func (w *Whisper) NewKeyPair() (string, error) {
+func (whisper *Whisper) NewKeyPair() (string, error) {
 	key, err := crypto.GenerateKey()
 	if err != nil || !validatePrivateKey(key) {
 		key, err = crypto.GenerateKey() // retry once
@@ -384,55 +386,55 @@ func (w *Whisper) NewKeyPair() (string, error) {
 		return "", fmt.Errorf("failed to generate ID: %s", err)
 	}
 
-	w.keyMu.Lock()
-	defer w.keyMu.Unlock()
+	whisper.keyMu.Lock()
+	defer whisper.keyMu.Unlock()
 
-	if w.privateKeys[id] != nil {
+	if whisper.privateKeys[id] != nil {
 		return "", fmt.Errorf("failed to generate unique ID")
 	}
-	w.privateKeys[id] = key
+	whisper.privateKeys[id] = key
 	return id, nil
 }
 
 // DeleteKeyPair deletes the specified key if it exists.
-func (w *Whisper) DeleteKeyPair(key string) bool {
-	w.keyMu.Lock()
-	defer w.keyMu.Unlock()
+func (whisper *Whisper) DeleteKeyPair(key string) bool {
+	whisper.keyMu.Lock()
+	defer whisper.keyMu.Unlock()
 
-	if w.privateKeys[key] != nil {
-		delete(w.privateKeys, key)
+	if whisper.privateKeys[key] != nil {
+		delete(whisper.privateKeys, key)
 		return true
 	}
 	return false
 }
 
 // AddKeyPair imports a asymmetric private key and returns it identifier.
-func (w *Whisper) AddKeyPair(key *ecdsa.PrivateKey) (string, error) {
+func (whisper *Whisper) AddKeyPair(key *ecdsa.PrivateKey) (string, error) {
 	id, err := GenerateRandomID()
 	if err != nil {
 		return "", fmt.Errorf("failed to generate ID: %s", err)
 	}
 
-	w.keyMu.Lock()
-	w.privateKeys[id] = key
-	w.keyMu.Unlock()
+	whisper.keyMu.Lock()
+	whisper.privateKeys[id] = key
+	whisper.keyMu.Unlock()
 
 	return id, nil
 }
 
 // HasKeyPair checks if the the whisper node is configured with the private key
 // of the specified public pair.
-func (w *Whisper) HasKeyPair(id string) bool {
-	w.keyMu.RLock()
-	defer w.keyMu.RUnlock()
-	return w.privateKeys[id] != nil
+func (whisper *Whisper) HasKeyPair(id string) bool {
+	whisper.keyMu.RLock()
+	defer whisper.keyMu.RUnlock()
+	return whisper.privateKeys[id] != nil
 }
 
 // GetPrivateKey retrieves the private key of the specified identity.
-func (w *Whisper) GetPrivateKey(id string) (*ecdsa.PrivateKey, error) {
-	w.keyMu.RLock()
-	defer w.keyMu.RUnlock()
-	key := w.privateKeys[id]
+func (whisper *Whisper) GetPrivateKey(id string) (*ecdsa.PrivateKey, error) {
+	whisper.keyMu.RLock()
+	defer whisper.keyMu.RUnlock()
+	key := whisper.privateKeys[id]
 	if key == nil {
 		return nil, fmt.Errorf("invalid id")
 	}
@@ -441,7 +443,7 @@ func (w *Whisper) GetPrivateKey(id string) (*ecdsa.PrivateKey, error) {
 
 // GenerateSymKey generates a random symmetric key and stores it under id,
 // which is then returned. Will be used in the future for session key exchange.
-func (w *Whisper) GenerateSymKey() (string, error) {
+func (whisper *Whisper) GenerateSymKey() (string, error) {
 	key := make([]byte, aesKeyLength)
 	_, err := crand.Read(key)
 	if err != nil {
@@ -455,18 +457,18 @@ func (w *Whisper) GenerateSymKey() (string, error) {
 		return "", fmt.Errorf("failed to generate ID: %s", err)
 	}
 
-	w.keyMu.Lock()
-	defer w.keyMu.Unlock()
+	whisper.keyMu.Lock()
+	defer whisper.keyMu.Unlock()
 
-	if w.symKeys[id] != nil {
+	if whisper.symKeys[id] != nil {
 		return "", fmt.Errorf("failed to generate unique ID")
 	}
-	w.symKeys[id] = key
+	whisper.symKeys[id] = key
 	return id, nil
 }
 
 // AddSymKeyDirect stores the key, and returns its id.
-func (w *Whisper) AddSymKeyDirect(key []byte) (string, error) {
+func (whisper *Whisper) AddSymKeyDirect(key []byte) (string, error) {
 	if len(key) != aesKeyLength {
 		return "", fmt.Errorf("wrong key size: %d", len(key))
 	}
@@ -476,23 +478,23 @@ func (w *Whisper) AddSymKeyDirect(key []byte) (string, error) {
 		return "", fmt.Errorf("failed to generate ID: %s", err)
 	}
 
-	w.keyMu.Lock()
-	defer w.keyMu.Unlock()
+	whisper.keyMu.Lock()
+	defer whisper.keyMu.Unlock()
 
-	if w.symKeys[id] != nil {
+	if whisper.symKeys[id] != nil {
 		return "", fmt.Errorf("failed to generate unique ID")
 	}
-	w.symKeys[id] = key
+	whisper.symKeys[id] = key
 	return id, nil
 }
 
 // AddSymKeyFromPassword generates the key from password, stores it, and returns its id.
-func (w *Whisper) AddSymKeyFromPassword(password string) (string, error) {
+func (whisper *Whisper) AddSymKeyFromPassword(password string) (string, error) {
 	id, err := GenerateRandomID()
 	if err != nil {
 		return "", fmt.Errorf("failed to generate ID: %s", err)
 	}
-	if w.HasSymKey(id) {
+	if whisper.HasSymKey(id) {
 		return "", fmt.Errorf("failed to generate unique ID")
 	}
 
@@ -503,59 +505,59 @@ func (w *Whisper) AddSymKeyFromPassword(password string) (string, error) {
 		return "", err
 	}
 
-	w.keyMu.Lock()
-	defer w.keyMu.Unlock()
+	whisper.keyMu.Lock()
+	defer whisper.keyMu.Unlock()
 
 	// double check is necessary, because deriveKeyMaterial() is very slow
-	if w.symKeys[id] != nil {
+	if whisper.symKeys[id] != nil {
 		return "", fmt.Errorf("critical error: failed to generate unique ID")
 	}
-	w.symKeys[id] = derived
+	whisper.symKeys[id] = derived
 	return id, nil
 }
 
 // HasSymKey returns true if there is a key associated with the given id.
 // Otherwise returns false.
-func (w *Whisper) HasSymKey(id string) bool {
-	w.keyMu.RLock()
-	defer w.keyMu.RUnlock()
-	return w.symKeys[id] != nil
+func (whisper *Whisper) HasSymKey(id string) bool {
+	whisper.keyMu.RLock()
+	defer whisper.keyMu.RUnlock()
+	return whisper.symKeys[id] != nil
 }
 
 // DeleteSymKey deletes the key associated with the name string if it exists.
-func (w *Whisper) DeleteSymKey(id string) bool {
-	w.keyMu.Lock()
-	defer w.keyMu.Unlock()
-	if w.symKeys[id] != nil {
-		delete(w.symKeys, id)
+func (whisper *Whisper) DeleteSymKey(id string) bool {
+	whisper.keyMu.Lock()
+	defer whisper.keyMu.Unlock()
+	if whisper.symKeys[id] != nil {
+		delete(whisper.symKeys, id)
 		return true
 	}
 	return false
 }
 
 // GetSymKey returns the symmetric key associated with the given id.
-func (w *Whisper) GetSymKey(id string) ([]byte, error) {
-	w.keyMu.RLock()
-	defer w.keyMu.RUnlock()
-	if w.symKeys[id] != nil {
-		return w.symKeys[id], nil
+func (whisper *Whisper) GetSymKey(id string) ([]byte, error) {
+	whisper.keyMu.RLock()
+	defer whisper.keyMu.RUnlock()
+	if whisper.symKeys[id] != nil {
+		return whisper.symKeys[id], nil
 	}
 	return nil, fmt.Errorf("non-existent key ID")
 }
 
 // Subscribe installs a new message handler used for filtering, decrypting
 // and subsequent storing of incoming messages.
-func (w *Whisper) Subscribe(f *Filter) (string, error) {
-	s, err := w.filters.Install(f)
+func (whisper *Whisper) Subscribe(f *Filter) (string, error) {
+	s, err := whisper.filters.Install(f)
 	if err == nil {
-		w.updateBloomFilter(f)
+		whisper.updateBloomFilter(f)
 	}
 	return s, err
 }
 
 // updateBloomFilter recalculates the new value of bloom filter,
 // and informs the peers if necessary.
-func (w *Whisper) updateBloomFilter(f *Filter) {
+func (whisper *Whisper) updateBloomFilter(f *Filter) {
 	aggregate := make([]byte, bloomFilterSize)
 	for _, t := range f.Topics {
 		top := BytesToTopic(t)
@@ -563,21 +565,21 @@ func (w *Whisper) updateBloomFilter(f *Filter) {
 		aggregate = addBloom(aggregate, b)
 	}
 
-	if !bloomFilterMatch(w.BloomFilter(), aggregate) {
+	if !bloomFilterMatch(whisper.BloomFilter(), aggregate) {
 		// existing bloom filter must be updated
-		aggregate = addBloom(w.BloomFilter(), aggregate)
-		w.SetBloomFilter(aggregate)
+		aggregate = addBloom(whisper.BloomFilter(), aggregate)
+		whisper.SetBloomFilter(aggregate)
 	}
 }
 
 // GetFilter returns the filter by id.
-func (w *Whisper) GetFilter(id string) *Filter {
-	return w.filters.Get(id)
+func (whisper *Whisper) GetFilter(id string) *Filter {
+	return whisper.filters.Get(id)
 }
 
 // Unsubscribe removes an installed message handler.
-func (w *Whisper) Unsubscribe(id string) error {
-	ok := w.filters.Uninstall(id)
+func (whisper *Whisper) Unsubscribe(id string) error {
+	ok := whisper.filters.Uninstall(id)
 	if !ok {
 		return fmt.Errorf("Unsubscribe: Invalid ID")
 	}
@@ -586,8 +588,8 @@ func (w *Whisper) Unsubscribe(id string) error {
 
 // Send injects a message into the whisper send queue, to be distributed in the
 // network in the coming cycles.
-func (w *Whisper) Send(envelope *Envelope) error {
-	ok, err := w.add(envelope)
+func (whisper *Whisper) Send(envelope *Envelope) error {
+	ok, err := whisper.add(envelope)
 	if err != nil {
 		return err
 	}
@@ -599,13 +601,13 @@ func (w *Whisper) Send(envelope *Envelope) error {
 
 // Start implements node.Service, starting the background data propagation thread
 // of the Whisper protocol.
-func (w *Whisper) Start(*p2p.Server) error {
+func (whisper *Whisper) Start(*p2p.Server) error {
 	log.Info("started whisper v." + ProtocolVersionStr)
-	go w.update()
+	go whisper.update()
 
 	numCPU := runtime.NumCPU()
 	for i := 0; i < numCPU; i++ {
-		go w.processQueue()
+		go whisper.processQueue()
 	}
 
 	return nil
@@ -613,26 +615,26 @@ func (w *Whisper) Start(*p2p.Server) error {
 
 // Stop implements node.Service, stopping the background data propagation thread
 // of the Whisper protocol.
-func (w *Whisper) Stop() error {
-	close(w.quit)
+func (whisper *Whisper) Stop() error {
+	close(whisper.quit)
 	log.Info("whisper stopped")
 	return nil
 }
 
 // HandlePeer is called by the underlying P2P layer when the whisper sub-protocol
 // connection is negotiated.
-func (wh *Whisper) HandlePeer(peer *p2p.Peer, rw p2p.MsgReadWriter) error {
+func (whisper *Whisper) HandlePeer(peer *p2p.Peer, rw p2p.MsgReadWriter) error {
 	// Create the new peer and start tracking it
-	whisperPeer := newPeer(wh, peer, rw)
+	whisperPeer := newPeer(whisper, peer, rw)
 
-	wh.peerMu.Lock()
-	wh.peers[whisperPeer] = struct{}{}
-	wh.peerMu.Unlock()
+	whisper.peerMu.Lock()
+	whisper.peers[whisperPeer] = struct{}{}
+	whisper.peerMu.Unlock()
 
 	defer func() {
-		wh.peerMu.Lock()
-		delete(wh.peers, whisperPeer)
-		wh.peerMu.Unlock()
+		whisper.peerMu.Lock()
+		delete(whisper.peers, whisperPeer)
+		whisper.peerMu.Unlock()
 	}()
 
 	// Run the peer handshake and state updates
@@ -642,11 +644,11 @@ func (wh *Whisper) HandlePeer(peer *p2p.Peer, rw p2p.MsgReadWriter) error {
 	whisperPeer.start()
 	defer whisperPeer.stop()
 
-	return wh.runMessageLoop(whisperPeer, rw)
+	return whisper.runMessageLoop(whisperPeer, rw)
 }
 
 // runMessageLoop reads and processes inbound messages directly to merge into client-global state.
-func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
+func (whisper *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
 	for {
 		// fetch the next packet
 		packet, err := rw.ReadMsg()
@@ -654,7 +656,7 @@ func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
 			log.Warn("message loop", "peer", p.peer.ID(), "err", err)
 			return err
 		}
-		if packet.Size > wh.MaxMessageSize() {
+		if packet.Size > whisper.MaxMessageSize() {
 			log.Warn("oversized message received", "peer", p.peer.ID())
 			return errors.New("oversized message received")
 		}
@@ -673,7 +675,7 @@ func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
 
 			trouble := false
 			for _, env := range envelopes {
-				cached, err := wh.add(env)
+				cached, err := whisper.add(env)
 				if err != nil {
 					trouble = true
 					log.Error("bad envelope received, peer will be disconnected", "peer", p.peer.ID(), "err", err)
@@ -726,17 +728,17 @@ func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
 					log.Warn("failed to decode direct message, peer will be disconnected", "peer", p.peer.ID(), "err", err)
 					return errors.New("invalid direct message")
 				}
-				wh.postEvent(&envelope, true)
+				whisper.postEvent(&envelope, true)
 			}
 		case p2pRequestCode:
 			// Must be processed if mail server is implemented. Otherwise ignore.
-			if wh.mailServer != nil {
+			if whisper.mailServer != nil {
 				var request Envelope
 				if err := packet.Decode(&request); err != nil {
 					log.Warn("failed to decode p2p request message, peer will be disconnected", "peer", p.peer.ID(), "err", err)
 					return errors.New("invalid p2p request")
 				}
-				wh.mailServer.DeliverMail(p, &request)
+				whisper.mailServer.DeliverMail(p, &request)
 			}
 		default:
 			// New message types might be implemented in the future versions of Whisper.
@@ -750,128 +752,126 @@ func (wh *Whisper) runMessageLoop(p *Peer, rw p2p.MsgReadWriter) error {
 // add inserts a new envelope into the message pool to be distributed within the
 // whisper network. It also inserts the envelope into the expiration pool at the
 // appropriate time-stamp. In case of error, connection should be dropped.
-func (wh *Whisper) add(envelope *Envelope) (bool, error) {
+func (whisper *Whisper) add(envelope *Envelope) (bool, error) {
 	now := uint32(time.Now().Unix())
 	sent := envelope.Expiry - envelope.TTL
 
 	if sent > now {
 		if sent-DefaultSyncAllowance > now {
 			return false, fmt.Errorf("envelope created in the future [%x]", envelope.Hash())
-		} else {
-			// recalculate PoW, adjusted for the time difference, plus one second for latency
-			envelope.calculatePoW(sent - now + 1)
 		}
+		// recalculate PoW, adjusted for the time difference, plus one second for latency
+		envelope.calculatePoW(sent - now + 1)
 	}
 
 	if envelope.Expiry < now {
 		if envelope.Expiry+DefaultSyncAllowance*2 < now {
 			return false, fmt.Errorf("very old message")
-		} else {
-			log.Debug("expired envelope dropped", "hash", envelope.Hash().Hex())
-			return false, nil // drop envelope without error
 		}
+		log.Debug("expired envelope dropped", "hash", envelope.Hash().Hex())
+		return false, nil // drop envelope without error
 	}
 
-	if uint32(envelope.size()) > wh.MaxMessageSize() {
+	if uint32(envelope.size()) > whisper.MaxMessageSize() {
 		return false, fmt.Errorf("huge messages are not allowed [%x]", envelope.Hash())
 	}
 
-	if envelope.PoW() < wh.MinPow() {
+	if envelope.PoW() < whisper.MinPow() {
 		// maybe the value was recently changed, and the peers did not adjust yet.
 		// in this case the previous value is retrieved by MinPowTolerance()
 		// for a short period of peer synchronization.
-		if envelope.PoW() < wh.MinPowTolerance() {
+		if envelope.PoW() < whisper.MinPowTolerance() {
 			return false, fmt.Errorf("envelope with low PoW received: PoW=%f, hash=[%v]", envelope.PoW(), envelope.Hash().Hex())
 		}
 	}
 
-	if !bloomFilterMatch(wh.BloomFilter(), envelope.Bloom()) {
+	if !bloomFilterMatch(whisper.BloomFilter(), envelope.Bloom()) {
 		// maybe the value was recently changed, and the peers did not adjust yet.
 		// in this case the previous value is retrieved by BloomFilterTolerance()
 		// for a short period of peer synchronization.
-		if !bloomFilterMatch(wh.BloomFilterTolerance(), envelope.Bloom()) {
+		if !bloomFilterMatch(whisper.BloomFilterTolerance(), envelope.Bloom()) {
 			return false, fmt.Errorf("envelope does not match bloom filter, hash=[%v], bloom: \n%x \n%x \n%x",
-				envelope.Hash().Hex(), wh.BloomFilter(), envelope.Bloom(), envelope.Topic)
+				envelope.Hash().Hex(), whisper.BloomFilter(), envelope.Bloom(), envelope.Topic)
 		}
 	}
 
 	hash := envelope.Hash()
 
-	wh.poolMu.Lock()
-	_, alreadyCached := wh.envelopes[hash]
+	whisper.poolMu.Lock()
+	_, alreadyCached := whisper.envelopes[hash]
 	if !alreadyCached {
-		wh.envelopes[hash] = envelope
-		if wh.expirations[envelope.Expiry] == nil {
-			wh.expirations[envelope.Expiry] = set.NewNonTS()
+		whisper.envelopes[hash] = envelope
+		if whisper.expirations[envelope.Expiry] == nil {
+			whisper.expirations[envelope.Expiry] = set.NewNonTS()
 		}
-		if !wh.expirations[envelope.Expiry].Has(hash) {
-			wh.expirations[envelope.Expiry].Add(hash)
+		if !whisper.expirations[envelope.Expiry].Has(hash) {
+			whisper.expirations[envelope.Expiry].Add(hash)
 		}
 	}
-	wh.poolMu.Unlock()
+	whisper.poolMu.Unlock()
 
 	if alreadyCached {
 		log.Trace("whisper envelope already cached", "hash", envelope.Hash().Hex())
 	} else {
 		log.Trace("cached whisper envelope", "hash", envelope.Hash().Hex())
-		wh.statsMu.Lock()
-		wh.stats.memoryUsed += envelope.size()
-		wh.statsMu.Unlock()
-		wh.postEvent(envelope, false) // notify the local node about the new message
-		if wh.mailServer != nil {
-			wh.mailServer.Archive(envelope)
+		whisper.statsMu.Lock()
+		whisper.stats.memoryUsed += envelope.size()
+		whisper.statsMu.Unlock()
+		whisper.postEvent(envelope, false) // notify the local node about the new message
+		if whisper.mailServer != nil {
+			whisper.mailServer.Archive(envelope)
 		}
 	}
 	return true, nil
 }
 
 // postEvent queues the message for further processing.
-func (w *Whisper) postEvent(envelope *Envelope, isP2P bool) {
+func (whisper *Whisper) postEvent(envelope *Envelope, isP2P bool) {
 	if isP2P {
-		w.p2pMsgQueue <- envelope
+		whisper.p2pMsgQueue <- envelope
 	} else {
-		w.checkOverflow()
-		w.messageQueue <- envelope
+		whisper.checkOverflow()
+		whisper.messageQueue <- envelope
 	}
 }
 
 // checkOverflow checks if message queue overflow occurs and reports it if necessary.
-func (w *Whisper) checkOverflow() {
-	queueSize := len(w.messageQueue)
+func (whisper *Whisper) checkOverflow() {
+	queueSize := len(whisper.messageQueue)
 
 	if queueSize == messageQueueLimit {
-		if !w.Overflow() {
-			w.settings.Store(overflowIdx, true)
+		if !whisper.Overflow() {
+			whisper.settings.Store(overflowIdx, true)
 			log.Warn("message queue overflow")
 		}
 	} else if queueSize <= messageQueueLimit/2 {
-		if w.Overflow() {
-			w.settings.Store(overflowIdx, false)
+		if whisper.Overflow() {
+			whisper.settings.Store(overflowIdx, false)
 			log.Warn("message queue overflow fixed (back to normal)")
 		}
 	}
 }
 
 // processQueue delivers the messages to the watchers during the lifetime of the whisper node.
-func (w *Whisper) processQueue() {
+func (whisper *Whisper) processQueue() {
 	var e *Envelope
 	for {
 		select {
-		case <-w.quit:
+		case <-whisper.quit:
 			return
 
-		case e = <-w.messageQueue:
-			w.filters.NotifyWatchers(e, false)
+		case e = <-whisper.messageQueue:
+			whisper.filters.NotifyWatchers(e, false)
 
-		case e = <-w.p2pMsgQueue:
-			w.filters.NotifyWatchers(e, true)
+		case e = <-whisper.p2pMsgQueue:
+			whisper.filters.NotifyWatchers(e, true)
 		}
 	}
 }
 
 // update loops until the lifetime of the whisper node, updating its internal
 // state by expiring stale messages from the pool.
-func (w *Whisper) update() {
+func (whisper *Whisper) update() {
 	// Start a ticker to check for expirations
 	expire := time.NewTicker(expirationCycle)
 
@@ -879,9 +879,9 @@ func (w *Whisper) update() {
 	for {
 		select {
 		case <-expire.C:
-			w.expire()
+			whisper.expire()
 
-		case <-w.quit:
+		case <-whisper.quit:
 			return
 		}
 	}
@@ -889,46 +889,46 @@ func (w *Whisper) update() {
 
 // expire iterates over all the expiration timestamps, removing all stale
 // messages from the pools.
-func (w *Whisper) expire() {
-	w.poolMu.Lock()
-	defer w.poolMu.Unlock()
+func (whisper *Whisper) expire() {
+	whisper.poolMu.Lock()
+	defer whisper.poolMu.Unlock()
 
-	w.statsMu.Lock()
-	defer w.statsMu.Unlock()
-	w.stats.reset()
+	whisper.statsMu.Lock()
+	defer whisper.statsMu.Unlock()
+	whisper.stats.reset()
 	now := uint32(time.Now().Unix())
-	for expiry, hashSet := range w.expirations {
+	for expiry, hashSet := range whisper.expirations {
 		if expiry < now {
 			// Dump all expired messages and remove timestamp
 			hashSet.Each(func(v interface{}) bool {
-				sz := w.envelopes[v.(common.Hash)].size()
-				delete(w.envelopes, v.(common.Hash))
-				w.stats.messagesCleared++
-				w.stats.memoryCleared += sz
-				w.stats.memoryUsed -= sz
+				sz := whisper.envelopes[v.(common.Hash)].size()
+				delete(whisper.envelopes, v.(common.Hash))
+				whisper.stats.messagesCleared++
+				whisper.stats.memoryCleared += sz
+				whisper.stats.memoryUsed -= sz
 				return true
 			})
-			w.expirations[expiry].Clear()
-			delete(w.expirations, expiry)
+			whisper.expirations[expiry].Clear()
+			delete(whisper.expirations, expiry)
 		}
 	}
 }
 
 // Stats returns the whisper node statistics.
-func (w *Whisper) Stats() Statistics {
-	w.statsMu.Lock()
-	defer w.statsMu.Unlock()
+func (whisper *Whisper) Stats() Statistics {
+	whisper.statsMu.Lock()
+	defer whisper.statsMu.Unlock()
 
-	return w.stats
+	return whisper.stats
 }
 
 // Envelopes retrieves all the messages currently pooled by the node.
-func (w *Whisper) Envelopes() []*Envelope {
-	w.poolMu.RLock()
-	defer w.poolMu.RUnlock()
+func (whisper *Whisper) Envelopes() []*Envelope {
+	whisper.poolMu.RLock()
+	defer whisper.poolMu.RUnlock()
 
-	all := make([]*Envelope, 0, len(w.envelopes))
-	for _, envelope := range w.envelopes {
+	all := make([]*Envelope, 0, len(whisper.envelopes))
+	for _, envelope := range whisper.envelopes {
 		all = append(all, envelope)
 	}
 	return all
@@ -936,13 +936,13 @@ func (w *Whisper) Envelopes() []*Envelope {
 
 // Messages iterates through all currently floating envelopes
 // and retrieves all the messages, that this filter could decrypt.
-func (w *Whisper) Messages(id string) []*ReceivedMessage {
+func (whisper *Whisper) Messages(id string) []*ReceivedMessage {
 	result := make([]*ReceivedMessage, 0)
-	w.poolMu.RLock()
-	defer w.poolMu.RUnlock()
+	whisper.poolMu.RLock()
+	defer whisper.poolMu.RUnlock()
 
-	if filter := w.filters.Get(id); filter != nil {
-		for _, env := range w.envelopes {
+	if filter := whisper.filters.Get(id); filter != nil {
+		for _, env := range whisper.envelopes {
 			msg := filter.processEnvelope(env)
 			if msg != nil {
 				result = append(result, msg)
@@ -953,11 +953,11 @@ func (w *Whisper) Messages(id string) []*ReceivedMessage {
 }
 
 // isEnvelopeCached checks if envelope with specific hash has already been received and cached.
-func (w *Whisper) isEnvelopeCached(hash common.Hash) bool {
-	w.poolMu.Lock()
-	defer w.poolMu.Unlock()
+func (whisper *Whisper) isEnvelopeCached(hash common.Hash) bool {
+	whisper.poolMu.Lock()
+	defer whisper.poolMu.Unlock()
 
-	_, exist := w.envelopes[hash]
+	_, exist := whisper.envelopes[hash]
 	return exist
 }
 
@@ -1019,7 +1019,7 @@ func BytesToUintBigEndian(b []byte) (res uint64) {
 
 // GenerateRandomID generates a random string, which is then returned to be used as a key id
 func GenerateRandomID() (id string, err error) {
-	buf := make([]byte, keyIdSize)
+	buf := make([]byte, keyIDSize)
 	_, err = crand.Read(buf)
 	if err != nil {
 		return "", err
diff --git a/whisper/whisperv6/whisper_test.go b/whisper/whisperv6/whisper_test.go
index fa14acb1b..23a289bfe 100644
--- a/whisper/whisperv6/whisper_test.go
+++ b/whisper/whisperv6/whisper_test.go
@@ -483,7 +483,7 @@ func TestExpiry(t *testing.T) {
 	}
 
 	params.TTL = 1
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -549,7 +549,7 @@ func TestCustomization(t *testing.T) {
 	params.Topic = BytesToTopic(f.Topics[2])
 	params.PoW = smallPoW
 	params.TTL = 3600 * 24 // one day
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -570,7 +570,7 @@ func TestCustomization(t *testing.T) {
 	}
 
 	params.TTL++
-	msg, err = NewSentMessage(params)
+	msg, err = newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -659,7 +659,7 @@ func TestSymmetricSendCycle(t *testing.T) {
 	params.PoW = filter1.PoW
 	params.WorkTime = 10
 	params.TTL = 50
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -737,7 +737,7 @@ func TestSymmetricSendWithoutAKey(t *testing.T) {
 	params.PoW = filter.PoW
 	params.WorkTime = 10
 	params.TTL = 50
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}
@@ -803,7 +803,7 @@ func TestSymmetricSendKeyMismatch(t *testing.T) {
 	params.PoW = filter.PoW
 	params.WorkTime = 10
 	params.TTL = 50
-	msg, err := NewSentMessage(params)
+	msg, err := newSentMessage(params)
 	if err != nil {
 		t.Fatalf("failed to create new message with seed %d: %s.", seed, err)
 	}