Merge pull request #236 from riking/patch-4

Cleanup commits

socketserver/server/backend.go

@@ -15,6 +15,7 @@ import (
 	"sync"
 	"time"
 
+	"github.com/FrankerFaceZ/FrankerFaceZ/socketserver/server/naclform"
 	cache "github.com/patrickmn/go-cache"
 	"golang.org/x/crypto/nacl/box"
 )
@@ -33,8 +34,7 @@ type backendInfo struct {
 	addTopicURL        string
 	announceStartupURL string
 
-	sharedKey [32]byte
+	secureForm naclform.ServerInfo
-	serverID  int
 
 	lastSuccess     map[string]time.Time
 	lastSuccessLock sync.Mutex
@@ -45,7 +45,7 @@ var Backend *backendInfo
 func setupBackend(config *ConfigFile) *backendInfo {
 	b := new(backendInfo)
 	Backend = b
-	b.serverID = config.ServerID
+	b.secureForm.ServerID = config.ServerID
 
 	b.HTTPClient.Timeout = 60 * time.Second
 	b.baseURL = config.BackendURL
@@ -68,7 +68,7 @@ func setupBackend(config *ConfigFile) *backendInfo {
 	copy(theirPublic[:], config.BackendPublicKey)
 	copy(ourPrivate[:], config.OurPrivateKey)
 
-	box.Precompute(&b.sharedKey, &theirPublic, &ourPrivate)
+	box.Precompute(&b.secureForm.SharedKey, &theirPublic, &ourPrivate)
 
 	return b
 }
@@ -119,7 +119,7 @@ func (backend *backendInfo) SendRemoteCommand(remoteCommand, data string, auth A
 		formData.Set("authenticated", "0")
 	}
 
-	sealedForm, err := backend.SealRequest(formData)
+	sealedForm, err := backend.secureForm.Seal(formData)
 	if err != nil {
 		return "", err
 	}
@@ -178,7 +178,7 @@ func (backend *backendInfo) SendRemoteCommand(remoteCommand, data string, auth A
 
 // SendAggregatedData sends aggregated emote usage and following data to the backend server.
 func (backend *backendInfo) SendAggregatedData(form url.Values) error {
-	sealedForm, err := backend.SealRequest(form)
+	sealedForm, err := backend.secureForm.Seal(form)
 	if err != nil {
 		return err
 	}
@@ -235,7 +235,7 @@ func (backend *backendInfo) sendTopicNotice(topic string, added bool) error {
 		formData.Set("added", "f")
 	}
 
-	sealedForm, err := backend.SealRequest(formData)
+	sealedForm, err := backend.secureForm.Seal(formData)
 	if err != nil {
 		return err
 	}

socketserver/server/backend_test.go

@@ -18,14 +18,14 @@ func TestSealRequest(t *testing.T) {
 		"QuickBrownFox": []string{"LazyDog"},
 	}
 
-	sealedValues, err := b.SealRequest(values)
+	sealedValues, err := b.secureForm.Seal(values)
 	if err != nil {
 		t.Fatal(err)
 	}
 	// sealedValues.Encode()
 	// id=0&msg=KKtbng49dOLLyjeuX5AnXiEe6P0uZwgeP_7mMB5vhP-wMAAPZw%3D%3D&nonce=-wRbUnifscisWUvhm3gBEXHN5QzrfzgV
 
-	unsealedValues, err := b.UnsealRequest(sealedValues)
+	unsealedValues, err := b.secureForm.Unseal(sealedValues)
 	if err != nil {
 		t.Fatal(err)
 	}

socketserver/server/commands.go

@@ -2,11 +2,9 @@ package server
 
 import (
 	"encoding/json"
-	"errors"
 	"fmt"
 	"log"
 	"net/url"
-	"strconv"
 	"sync"
 	"time"
 
@@ -96,7 +94,7 @@ func DispatchC2SCommand(conn *websocket.Conn, client *ClientInfo, msg ClientMess
 	}
 }
 
-func callHandler(handler CommandHandler, conn *websocket.Conn, client *ClientInfo, cmsg ClientMessage) (rmsg ClientMessage, err error) {
+func callHandler(handler CommandHandler, conn *websocket.Conn, client *ClientInfo, cmsg ClientMessage) (_ ClientMessage, err error) {
 	defer func() {
 		if r := recover(); r != nil {
 			var ok bool
@@ -112,7 +110,7 @@ func callHandler(handler CommandHandler, conn *websocket.Conn, client *ClientInf
 
 // C2SHello implements the `hello` C2S Command.
 // It calls SubscribeGlobal() and SubscribeDefaults() with the client, and fills out ClientInfo.Version and ClientInfo.ClientID.
-func C2SHello(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SHello(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (_ ClientMessage, err error) {
 	ary, ok := msg.Arguments.([]interface{})
 	if !ok {
 		err = ErrExpectedTwoStrings
@@ -163,16 +161,16 @@ func C2SHello(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg
 	}, nil
 }
 
-func C2SPing(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SPing(*websocket.Conn, *ClientInfo, ClientMessage) (ClientMessage, error) {
 	return ClientMessage{
 		Arguments: float64(time.Now().UnixNano()/1000) / 1000,
 	}, nil
 }
 
-func C2SSetUser(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SSetUser(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
 	username, err := msg.ArgumentsAsString()
 	if err != nil {
-		return
+		return ClientMessage{}, err
 	}
 
 	username = copyString(username)
@@ -192,29 +190,24 @@ func C2SSetUser(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rm
 	return ResponseSuccess, nil
 }
 
-func C2SReady(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SReady(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
-	//	disconnectAt, err := msg.ArgumentsAsInt()
-	//	if err != nil {
-	//		return
-	//	}
-
 	client.Mutex.Lock()
 	client.ReadyComplete = true
 	client.Mutex.Unlock()
 
 	client.MsgChannelKeepalive.Add(1)
 	go func() {
-		client.Send(ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand})
+		client.Send(msg.Reply(SuccessCommand, nil))
 		SendBacklogForNewClient(client)
 		client.MsgChannelKeepalive.Done()
 	}()
 	return ClientMessage{Command: AsyncResponseCommand}, nil
 }
 
-func C2SSubscribe(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SSubscribe(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
 	channel, err := msg.ArgumentsAsString()
 	if err != nil {
-		return
+		return ClientMessage{}, err
 	}
 
 	channel = PubSubChannelPool.Intern(channel)
@@ -238,10 +231,10 @@ func C2SSubscribe(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (
 
 // C2SUnsubscribe implements the `unsub` C2S Command.
 // It removes the channel from ClientInfo.CurrentChannels and calls UnsubscribeSingleChat.
-func C2SUnsubscribe(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SUnsubscribe(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
 	channel, err := msg.ArgumentsAsString()
 	if err != nil {
-		return
+		return ClientMessage{}, err
 	}
 
 	channel = PubSubChannelPool.Intern(channel)
@@ -256,9 +249,8 @@ func C2SUnsubscribe(conn *websocket.Conn, client *ClientInfo, msg ClientMessage)
 }
 
 // C2SSurvey implements the survey C2S Command.
-// Surveys are discarded.s
+func C2SSurvey(*websocket.Conn, *ClientInfo, ClientMessage) (ClientMessage, error) {
-func C2SSurvey(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+	// Surveys are not collected.
-	// Discard
 	return ResponseSuccess, nil
 }
 
@@ -276,7 +268,7 @@ var followEventsLock sync.Mutex
 
 // C2STrackFollow implements the `track_follow` C2S Command.
 // It adds the record to `followEvents`, which is submitted to the backend on a timer.
-func C2STrackFollow(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2STrackFollow(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (_ ClientMessage, err error) {
 	channel, following, err := msg.ArgumentsAsStringAndBool()
 	if err != nil {
 		return
@@ -293,68 +285,18 @@ func C2STrackFollow(conn *websocket.Conn, client *ClientInfo, msg ClientMessage)
 }
 
 // AggregateEmoteUsage is a map from emoteID to a map from chatroom name to usage count.
-var aggregateEmoteUsage = make(map[int]map[string]int)
+//var aggregateEmoteUsage = make(map[int]map[string]int)
 
 // AggregateEmoteUsageLock is the lock for AggregateEmoteUsage.
-var aggregateEmoteUsageLock sync.Mutex
+//var aggregateEmoteUsageLock sync.Mutex
 
 // ErrNegativeEmoteUsage is emitted when the submitted emote usage is negative.
-var ErrNegativeEmoteUsage = errors.New("Emote usage count cannot be negative")
+//var ErrNegativeEmoteUsage = errors.New("Emote usage count cannot be negative")
 
 // C2SEmoticonUses implements the `emoticon_uses` C2S Command.
 // msg.Arguments are in the JSON format of [1]map[emoteID]map[ChatroomName]float64.
-func C2SEmoticonUses(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SEmoticonUses(*websocket.Conn, *ClientInfo, ClientMessage) (ClientMessage, error) {
-	// if this panics, will be caught by callHandler
+	// We do not collect emote usage data
-	mapRoot := msg.Arguments.([]interface{})[0].(map[string]interface{})
-
-	// Validate: male suire
-	for strEmote, val1 := range mapRoot {
-		_, err = strconv.Atoi(strEmote)
-		if err != nil {
-			return
-		}
-		mapInner := val1.(map[string]interface{})
-		for _, val2 := range mapInner {
-			var count = int(val2.(float64))
-			if count <= 0 {
-				err = ErrNegativeEmoteUsage
-				return
-			}
-		}
-	}
-
-	aggregateEmoteUsageLock.Lock()
-	defer aggregateEmoteUsageLock.Unlock()
-
-	var total int
-
-	for strEmote, val1 := range mapRoot {
-		var emoteID int
-		emoteID, err = strconv.Atoi(strEmote)
-		if err != nil {
-			return
-		}
-
-		destMapInner, ok := aggregateEmoteUsage[emoteID]
-		if !ok {
-			destMapInner = make(map[string]int)
-			aggregateEmoteUsage[emoteID] = destMapInner
-		}
-
-		mapInner := val1.(map[string]interface{})
-		for roomName, val2 := range mapInner {
-			var count = int(val2.(float64))
-			if count > 200 {
-				count = 200
-			}
-			roomName = TwitchChannelPool.Intern(roomName)
-			destMapInner[roomName] += count
-			total += count
-		}
-	}
-
-	Statistics.EmotesReportedTotal += uint64(total)
-
 	return ResponseSuccess, nil
 }
 
@@ -371,10 +313,10 @@ func aggregateDataSender_do() {
 	follows := followEvents
 	followEvents = nil
 	followEventsLock.Unlock()
-	aggregateEmoteUsageLock.Lock()
+	//aggregateEmoteUsageLock.Lock()
-	emoteUsage := aggregateEmoteUsage
+	//emoteUsage := aggregateEmoteUsage
-	aggregateEmoteUsage = make(map[int]map[string]int)
+	//aggregateEmoteUsage = make(map[int]map[string]int)
-	aggregateEmoteUsageLock.Unlock()
+	//aggregateEmoteUsageLock.Unlock()
 
 	reportForm := url.Values{}
 
@@ -386,10 +328,10 @@ func aggregateDataSender_do() {
 	}
 
 	strEmoteUsage := make(map[string]map[string]int)
-	for emoteID, usageByChannel := range emoteUsage {
+	//for emoteID, usageByChannel := range emoteUsage {
-		strEmoteID := strconv.Itoa(emoteID)
+	//	strEmoteID := strconv.Itoa(emoteID)
-		strEmoteUsage[strEmoteID] = usageByChannel
+	//	strEmoteUsage[strEmoteID] = usageByChannel
-	}
+	//}
 	emoteJSON, err := json.Marshal(strEmoteUsage)
 	if err != nil {
 		log.Println("error reporting aggregate data:", err)
@@ -429,7 +371,7 @@ var bunchGroup singleflight.Group
 
 // C2SHandleBunchedCommand handles C2S Commands such as `get_link`.
 // It makes a request to the backend server for the data, but any other requests coming in while the first is pending also get the responses from the first one.
-func C2SHandleBunchedCommand(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
+func C2SHandleBunchedCommand(_ *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
 	key := fmt.Sprintf("%s:%s", msg.Command, msg.origArguments)
 
 	resultCh := bunchGroup.DoChan(key, func() (interface{}, error) {
@@ -439,29 +381,21 @@ func C2SHandleBunchedCommand(conn *websocket.Conn, client *ClientInfo, msg Clien
 	client.MsgChannelKeepalive.Add(1)
 	go func() {
 		result := <-resultCh
-		var reply ClientMessage
+		if efb, ok := result.Err.(ErrForwardedFromBackend); ok {
-		reply.MessageID = msg.MessageID
+			client.Send(msg.Reply(ErrorCommand, efb.JSONError))
-		if result.Err != nil {
+		} else if result.Err != nil {
-			reply.Command = ErrorCommand
+			client.Send(msg.Reply(ErrorCommand, result.Err.Error()))
-			if efb, ok := result.Err.(ErrForwardedFromBackend); ok {
-				reply.Arguments = efb.JSONError
-			} else {
-				reply.Arguments = result.Err.Error()
-			}
 		} else {
-			reply.Command = SuccessCommand
+			client.Send(msg.ReplyJSON(SuccessCommand, result.Val.(string)))
-			reply.origArguments = result.Val.(string)
-			reply.parseOrigArguments()
 		}
 
-		client.Send(reply)
 		client.MsgChannelKeepalive.Done()
 	}()
 
 	return ClientMessage{Command: AsyncResponseCommand}, nil
 }
 
-func C2SHandleRemoteCommand(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (rmsg ClientMessage, err error) {
+func C2SHandleRemoteCommand(conn *websocket.Conn, client *ClientInfo, msg ClientMessage) (ClientMessage, error) {
 	client.MsgChannelKeepalive.Add(1)
 	go doRemoteCommand(conn, msg, client)
 
@@ -477,7 +411,7 @@ func doRemoteCommand(conn *websocket.Conn, msg ClientMessage, client *ClientInfo
 	if err == ErrAuthorizationNeeded {
 		if client.TwitchUsername == "" {
 			// Not logged in
-			client.Send(ClientMessage{MessageID: msg.MessageID, Command: ErrorCommand, Arguments: AuthorizationNeededError})
+			client.Send(msg.Reply(ErrorCommand, AuthorizationNeededError))
 			client.MsgChannelKeepalive.Done()
 			return
 		}
@@ -485,19 +419,17 @@ func doRemoteCommand(conn *websocket.Conn, msg ClientMessage, client *ClientInfo
 			if success {
 				doRemoteCommand(conn, msg, client)
 			} else {
-				client.Send(ClientMessage{MessageID: msg.MessageID, Command: ErrorCommand, Arguments: AuthorizationFailedErrorString})
+				client.Send(msg.Reply(ErrorCommand, AuthorizationFailedErrorString))
 				client.MsgChannelKeepalive.Done()
 			}
 		})
 		return // without keepalive.Done()
 	} else if bfe, ok := err.(ErrForwardedFromBackend); ok {
-		client.Send(ClientMessage{MessageID: msg.MessageID, Command: ErrorCommand, Arguments: bfe.JSONError})
+		client.Send(msg.Reply(ErrorCommand, bfe.JSONError))
 	} else if err != nil {
-		client.Send(ClientMessage{MessageID: msg.MessageID, Command: ErrorCommand, Arguments: err.Error()})
+		client.Send(msg.Reply(ErrorCommand, err.Error()))
 	} else {
-		msg := ClientMessage{MessageID: msg.MessageID, Command: SuccessCommand, origArguments: resp}
+		client.Send(msg.ReplyJSON(SuccessCommand, resp))
-		msg.parseOrigArguments()
-		client.Send(msg)
 	}
 	client.MsgChannelKeepalive.Done()
 }

socketserver/server/handlecore.go

@@ -104,7 +104,7 @@ func SetupServerAndHandle(config *ConfigFile, serveMux *http.ServeMux) {
 	serveMux.HandleFunc("/cached_pub", HTTPBackendCachedPublish)
 	serveMux.HandleFunc("/get_sub_count", HTTPGetSubscriberCount)
 
-	announceForm, err := Backend.SealRequest(url.Values{
+	announceForm, err := Backend.secureForm.Seal(url.Values{
 		"startup": []string{"1"},
 	})
 	if err != nil {
@@ -249,11 +249,21 @@ func HTTPHandleRootURL(w http.ResponseWriter, r *http.Request) {
 	}
 }
 
+type fatalDecodeError string
+
+func (e fatalDecodeError) Error() string {
+	return string(e)
+}
+
+func (e fatalDecodeError) IsFatal() bool {
+	return true
+}
+
 // ErrProtocolGeneric is sent in a ErrorCommand Reply.
-var ErrProtocolGeneric error = errors.New("FFZ Socket protocol error.")
+var ErrProtocolGeneric error = fatalDecodeError("FFZ Socket protocol error.")
 
 // ErrProtocolNegativeMsgID is sent in a ErrorCommand Reply when a negative MessageID is received.
-var ErrProtocolNegativeMsgID error = errors.New("FFZ Socket protocol error: negative or zero message ID.")
+var ErrProtocolNegativeMsgID error = fatalDecodeError("FFZ Socket protocol error: negative or zero message ID.")
 
 // ErrExpectedSingleString is sent in a ErrorCommand Reply when the Arguments are of the wrong type.
 var ErrExpectedSingleString = errors.New("Error: Expected single string as arguments.")
@@ -344,7 +354,7 @@ func RunSocketConnection(conn *websocket.Conn) {
 	})
 
 	// All set up, now enter the work loop
-	go runSocketReader(conn, _errorChan, _clientChan, stoppedChan)
+	go runSocketReader(conn, &client, _errorChan, _clientChan)
 	closeReason := runSocketWriter(conn, &client, _errorChan, _clientChan, _serverMessageChan)
 
 	// Exit
@@ -376,12 +386,14 @@ func RunSocketConnection(conn *websocket.Conn) {
 	}
 }
 
-func runSocketReader(conn *websocket.Conn, errorChan chan<- error, clientChan chan<- ClientMessage, stoppedChan <-chan struct{}) {
+func runSocketReader(conn *websocket.Conn, client *ClientInfo, errorChan chan<- error, clientChan chan<- ClientMessage) {
 	var msg ClientMessage
 	var messageType int
 	var packet []byte
 	var err error
 
+	stoppedChan := client.MsgChannelIsDone
+
 	defer close(errorChan)
 	defer close(clientChan)
 
@@ -395,8 +407,15 @@ func runSocketReader(conn *websocket.Conn, errorChan chan<- error, clientChan ch
 			break
 		}
 
-		UnmarshalClientMessage(packet, messageType, &msg)
+		msg = ClientMessage{}
-		if msg.MessageID == 0 {
+		msgErr := UnmarshalClientMessage(packet, messageType, &msg)
+		if _, ok := msgErr.(interface{IsFatal() bool}); ok {
+			errorChan <- msgErr
+			continue
+		} else if msgErr != nil {
+			client.Send(msg.Reply(ErrorCommand, msgErr.Error()))
+			continue
+		} else if msg.MessageID == 0 {
 			continue
 		}
 		select {
@@ -505,7 +524,7 @@ func SendMessage(conn *websocket.Conn, msg ClientMessage) {
 }
 
 // UnmarshalClientMessage unpacks websocket TextMessage into a ClientMessage provided in the `v` parameter.
-func UnmarshalClientMessage(data []byte, payloadType int, v interface{}) (err error) {
+func UnmarshalClientMessage(data []byte, _ int, v interface{}) (err error) {
 	var spaceIdx int
 
 	out := v.(*ClientMessage)
@@ -514,11 +533,11 @@ func UnmarshalClientMessage(data []byte, payloadType int, v interface{}) (err er
 	// Message ID
 	spaceIdx = strings.IndexRune(dataStr, ' ')
 	if spaceIdx == -1 {
-		return ErrProtocolGeneric
+		return ErrProtocolGeneric // fatal error
 	}
 	messageID, err := strconv.Atoi(dataStr[:spaceIdx])
 	if messageID < -1 || messageID == 0 {
-		return ErrProtocolNegativeMsgID
+		return ErrProtocolNegativeMsgID // fatal error
 	}
 
 	out.MessageID = messageID
@@ -551,7 +570,8 @@ func (cm *ClientMessage) parseOrigArguments() error {
 	return nil
 }
 
-func MarshalClientMessage(clientMessage interface{}) (payloadType int, data []byte, err error) {
+// returns payloadType, data, err
+func MarshalClientMessage(clientMessage interface{}) (int, []byte, error) {
 	var msg ClientMessage
 	var ok bool
 	msg, ok = clientMessage.(ClientMessage)

socketserver/server/naclform/seal.go

@@ -0,0 +1,96 @@
+package naclform
+
+import (
+	"bytes"
+	"crypto/rand"
+	"encoding/base64"
+	"errors"
+	"net/url"
+	"strconv"
+	"strings"
+
+	"golang.org/x/crypto/nacl/box"
+)
+
+var ErrorShortNonce = errors.New("Nonce too short.")
+var ErrorInvalidSignature = errors.New("Invalid signature or contents")
+
+type ServerInfo struct {
+	SharedKey [32]byte
+	ServerID  int
+}
+
+func fillCryptoRandom(buf []byte) error {
+	remaining := len(buf)
+	for remaining > 0 {
+		count, err := rand.Read(buf)
+		if err != nil {
+			return err
+		}
+		remaining -= count
+	}
+	return nil
+}
+
+func (i *ServerInfo) Seal(form url.Values) (url.Values, error) {
+	var nonce [24]byte
+	var err error
+
+	err = fillCryptoRandom(nonce[:])
+	if err != nil {
+		return nil, err
+	}
+
+	cipherMsg := box.SealAfterPrecomputation(nil, []byte(form.Encode()), &nonce, &i.SharedKey)
+
+	bufMessage := new(bytes.Buffer)
+	enc := base64.NewEncoder(base64.URLEncoding, bufMessage)
+	enc.Write(cipherMsg)
+	enc.Close()
+	cipherString := bufMessage.String()
+
+	bufNonce := new(bytes.Buffer)
+	enc = base64.NewEncoder(base64.URLEncoding, bufNonce)
+	enc.Write(nonce[:])
+	enc.Close()
+	nonceString := bufNonce.String()
+
+	retval := url.Values{
+		"nonce": []string{nonceString},
+		"msg":   []string{cipherString},
+		"id":    []string{strconv.Itoa(i.ServerID)},
+	}
+
+	return retval, nil
+}
+
+func (i *ServerInfo) Unseal(form url.Values) (url.Values, error) {
+	var nonce [24]byte
+
+	nonceString := form.Get("nonce")
+	dec := base64.NewDecoder(base64.URLEncoding, strings.NewReader(nonceString))
+	count, err := dec.Read(nonce[:])
+	if err != nil {
+		return nil, err
+	}
+	if count != 24 {
+		return nil, ErrorShortNonce
+	}
+
+	cipherString := form.Get("msg")
+	dec = base64.NewDecoder(base64.URLEncoding, strings.NewReader(cipherString))
+	cipherBuffer := new(bytes.Buffer)
+	cipherBuffer.ReadFrom(dec)
+
+	message, ok := box.OpenAfterPrecomputation(nil, cipherBuffer.Bytes(), &nonce, &i.SharedKey)
+	if !ok {
+		return nil, ErrorInvalidSignature
+	}
+
+	retValues, err := url.ParseQuery(string(message))
+	if err != nil {
+		return nil, ErrorInvalidSignature
+	}
+
+	return retValues, nil
+}

socketserver/server/publisher.go

@@ -123,7 +123,7 @@ func saveLastMessage(cmd Command, channel string, expires time.Time, data string
 
 func HTTPBackendDropBacklog(w http.ResponseWriter, r *http.Request) {
 	r.ParseForm()
-	formData, err := Backend.UnsealRequest(r.Form)
+	formData, err := Backend.secureForm.Unseal(r.Form)
 	if err != nil {
 		w.WriteHeader(403)
 		fmt.Fprintf(w, "Error: %v", err)
@@ -160,7 +160,7 @@ func rateLimitFromRequest(r *http.Request) (rate.Limiter, error) {
 // If the 'expires' parameter is not specified, the message will not expire (though it is only kept in-memory).
 func HTTPBackendCachedPublish(w http.ResponseWriter, r *http.Request) {
 	r.ParseForm()
-	formData, err := Backend.UnsealRequest(r.Form)
+	formData, err := Backend.secureForm.Unseal(r.Form)
 	if err != nil {
 		w.WriteHeader(403)
 		fmt.Fprintf(w, "Error: %v", err)
@@ -227,7 +227,7 @@ func HTTPBackendCachedPublish(w http.ResponseWriter, r *http.Request) {
 // If "scope" is "global", then "channel" is not used.
 func HTTPBackendUncachedPublish(w http.ResponseWriter, r *http.Request) {
 	r.ParseForm()
-	formData, err := Backend.UnsealRequest(r.Form)
+	formData, err := Backend.secureForm.Unseal(r.Form)
 	if err != nil {
 		w.WriteHeader(403)
 		fmt.Fprintf(w, "Error: %v", err)
@@ -292,7 +292,7 @@ func HTTPBackendUncachedPublish(w http.ResponseWriter, r *http.Request) {
 // A "global" option is not available, use fetch(/stats).CurrentClientCount instead.
 func HTTPGetSubscriberCount(w http.ResponseWriter, r *http.Request) {
 	r.ParseForm()
-	formData, err := Backend.UnsealRequest(r.Form)
+	formData, err := Backend.secureForm.Unseal(r.Form)
 	if err != nil {
 		w.WriteHeader(403)
 		fmt.Fprintf(w, "Error: %v", err)

socketserver/server/stats.go

@@ -209,7 +209,7 @@ func updateSysMem() {
 }
 
 // HTTPShowStatistics handles the /stats endpoint. It writes out the Statistics object as indented JSON.
-func HTTPShowStatistics(w http.ResponseWriter, r *http.Request) {
+func HTTPShowStatistics(w http.ResponseWriter, _ *http.Request) {
 	w.Header().Set("Content-Type", "application/json")
 
 	updateStatsIfNeeded()

socketserver/server/testinfra_test.go

@@ -97,7 +97,7 @@ func (er *TExpectedBackendRequest) String() string {
 	if MethodIsPost == "" {
 		return er.Path
 	}
-	return fmt.Sprint("%s %s: %s", MethodIsPost, er.Path, er.PostForm.Encode())
+	return fmt.Sprintf("%s %s: %s", MethodIsPost, er.Path, er.PostForm.Encode())
 }
 
 type TBackendRequestChecker struct {
@@ -123,7 +123,7 @@ func (backend *TBackendRequestChecker) ServeHTTP(w http.ResponseWriter, r *http.
 
 	r.ParseForm()
 
-	unsealedForm, err := Backend.UnsealRequest(r.PostForm)
+	unsealedForm, err := Backend.secureForm.Unseal(r.PostForm)
 	if err != nil {
 		backend.tb.Errorf("Failed to unseal backend request: %v", err)
 	}
@@ -276,7 +276,7 @@ func TSealForSavePubMsg(tb testing.TB, cmd Command, channel string, arguments in
 	}
 	form.Set("time", strconv.FormatInt(time.Now().Unix(), 10))
 
-	sealed, err := Backend.SealRequest(form)
+	sealed, err := Backend.secureForm.Seal(form)
 	if err != nil {
 		tb.Error(err)
 		return nil, err
@@ -300,7 +300,7 @@ func TSealForUncachedPubMsg(tb testing.TB, cmd Command, channel string, argument
 	form.Set("time", time.Now().Format(time.UnixDate))
 	form.Set("scope", scope)
 
-	sealed, err := Backend.SealRequest(form)
+	sealed, err := Backend.secureForm.Seal(form)
 	if err != nil {
 		tb.Error(err)
 		return nil, err

socketserver/server/types.go

@@ -64,6 +64,24 @@ type ClientMessage struct {
 	origArguments string
 }
 
+func (cm ClientMessage) Reply(cmd Command, args interface{}) ClientMessage {
+	return ClientMessage{
+		MessageID: cm.MessageID,
+		Command:   cmd,
+		Arguments: args,
+	}
+}
+
+func (cm ClientMessage) ReplyJSON(cmd Command, argsJSON string) ClientMessage {
+	n := ClientMessage{
+		MessageID:     cm.MessageID,
+		Command:       cmd,
+		origArguments: argsJSON,
+	}
+	n.parseOrigArguments()
+	return n
+}
+
 type AuthInfo struct {
 	// The client's claimed username on Twitch.
 	TwitchUsername string

socketserver/server/usercount.go

@@ -46,11 +46,6 @@ var uniqueCtrWritingToken chan usageToken
 
 var CounterLocation *time.Location = time.FixedZone("UTC-5", int((time.Hour*-5)/time.Second))
 
-func TruncateToMidnight(at time.Time) time.Time {
-	year, month, day := at.Date()
-	return time.Date(year, month, day, 0, 0, 0, 0, CounterLocation)
-}
-
 // GetCounterPeriod calculates the start and end timestamps for the HLL measurement period that includes the 'at' timestamp.
 func GetCounterPeriod(at time.Time) (start time.Time, end time.Time) {
 	year, month, day := at.Date()
@@ -132,7 +127,7 @@ func HTTPShowHLL(w http.ResponseWriter, r *http.Request) {
 	hllFileServer.ServeHTTP(w, r)
 }
 
-func HTTPWriteHLL(w http.ResponseWriter, r *http.Request) {
+func HTTPWriteHLL(w http.ResponseWriter, _ *http.Request) {
 	writeHLL()
 	w.WriteHeader(200)
 	w.Write([]byte("ok"))
@@ -150,9 +145,7 @@ func loadUniqueUsers() {
 	now := time.Now().In(CounterLocation)
 	uniqueCounter.Start, uniqueCounter.End = GetCounterPeriod(now)
 	err = loadHLL(now, &uniqueCounter)
-	isIgnorableError := err != nil && (false ||
+	isIgnorableError := err != nil && (os.IsNotExist(err) || err == io.EOF)
-		(os.IsNotExist(err)) ||
-		(err == io.EOF))
 
 	if isIgnorableError {
 		// file didn't finish writing
@@ -227,10 +220,10 @@ func rolloverCounters_do() {
 
 		// Attempt to rescue the data into the log
 		var buf bytes.Buffer
-		bytes, err := uniqueCounter.Counter.GobEncode()
+		by, err := uniqueCounter.Counter.GobEncode()
 		if err == nil {
 			enc := base64.NewEncoder(base64.StdEncoding, &buf)
-			enc.Write(bytes)
+			enc.Write(by)
 			enc.Close()
 			log.Print("data for ", GetHLLFilename(uniqueCounter.Start), ":", buf.String())
 		}

socketserver/server/utils.go

@@ -1,103 +1,9 @@
 package server
 
-import (
-	"bytes"
-	"crypto/rand"
-	"encoding/base64"
-	"errors"
-	"net/url"
-	"strconv"
-	"strings"
-
-	"golang.org/x/crypto/nacl/box"
-)
-
-func FillCryptoRandom(buf []byte) error {
-	remaining := len(buf)
-	for remaining > 0 {
-		count, err := rand.Read(buf)
-		if err != nil {
-			return err
-		}
-		remaining -= count
-	}
-	return nil
-}
-
 func copyString(s string) string {
 	return string([]byte(s))
 }
 
-func (backend *backendInfo) SealRequest(form url.Values) (url.Values, error) {
-	var nonce [24]byte
-	var err error
-
-	err = FillCryptoRandom(nonce[:])
-	if err != nil {
-		return nil, err
-	}
-
-	cipherMsg := box.SealAfterPrecomputation(nil, []byte(form.Encode()), &nonce, &backend.sharedKey)
-
-	bufMessage := new(bytes.Buffer)
-	enc := base64.NewEncoder(base64.URLEncoding, bufMessage)
-	enc.Write(cipherMsg)
-	enc.Close()
-	cipherString := bufMessage.String()
-
-	bufNonce := new(bytes.Buffer)
-	enc = base64.NewEncoder(base64.URLEncoding, bufNonce)
-	enc.Write(nonce[:])
-	enc.Close()
-	nonceString := bufNonce.String()
-
-	retval := url.Values{
-		"nonce": []string{nonceString},
-		"msg":   []string{cipherString},
-		"id":    []string{strconv.Itoa(Backend.serverID)},
-	}
-
-	return retval, nil
-}
-
-var ErrorShortNonce = errors.New("Nonce too short.")
-var ErrorInvalidSignature = errors.New("Invalid signature or contents")
-
-func (backend *backendInfo) UnsealRequest(form url.Values) (url.Values, error) {
-	var nonce [24]byte
-
-	nonceString := form.Get("nonce")
-	dec := base64.NewDecoder(base64.URLEncoding, strings.NewReader(nonceString))
-	count, err := dec.Read(nonce[:])
-	if err != nil {
-		Statistics.BackendVerifyFails++
-		return nil, err
-	}
-	if count != 24 {
-		Statistics.BackendVerifyFails++
-		return nil, ErrorShortNonce
-	}
-
-	cipherString := form.Get("msg")
-	dec = base64.NewDecoder(base64.URLEncoding, strings.NewReader(cipherString))
-	cipherBuffer := new(bytes.Buffer)
-	cipherBuffer.ReadFrom(dec)
-
-	message, ok := box.OpenAfterPrecomputation(nil, cipherBuffer.Bytes(), &nonce, &backend.sharedKey)
-	if !ok {
-		Statistics.BackendVerifyFails++
-		return nil, ErrorInvalidSignature
-	}
-
-	retValues, err := url.ParseQuery(string(message))
-	if err != nil {
-		Statistics.BackendVerifyFails++
-		return nil, ErrorInvalidSignature
-	}
-
-	return retValues, nil
-}
-
 func AddToSliceS(ary *[]string, val string) bool {
 	slice := *ary
 	for _, v := range slice {
@@ -161,17 +67,3 @@ func RemoveFromSliceCl(ary *[]*ClientInfo, val *ClientInfo) bool {
 	*ary = slice
 	return true
 }
-
-func AddToSliceB(ary *[]bunchSubscriber, client *ClientInfo, mid int) bool {
-	newSub := bunchSubscriber{Client: client, MessageID: mid}
-	slice := *ary
-	for _, v := range slice {
-		if v == newSub {
-			return false
-		}
-	}
-
-	slice = append(slice, newSub)
-	*ary = slice
-	return true
-}