socket.io-client-swift/Source/WebSocket.swift

959 lines
39 KiB
Swift

//////////////////////////////////////////////////////////////////////////////////////////////////
//
// Websocket.swift
//
// Created by Dalton Cherry on 7/16/14.
// Copyright (c) 2014-2016 Dalton Cherry.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
//////////////////////////////////////////////////////////////////////////////////////////////////
import Foundation
import CoreFoundation
import Security
public let WebsocketDidConnectNotification = "WebsocketDidConnectNotification"
public let WebsocketDidDisconnectNotification = "WebsocketDidDisconnectNotification"
public let WebsocketDisconnectionErrorKeyName = "WebsocketDisconnectionErrorKeyName"
public protocol WebSocketDelegate: class {
func websocketDidConnect(socket: WebSocket)
func websocketDidDisconnect(socket: WebSocket, error: NSError?)
func websocketDidReceiveMessage(socket: WebSocket, text: String)
func websocketDidReceiveData(socket: WebSocket, data: Data)
}
public protocol WebSocketPongDelegate: class {
func websocketDidReceivePong(socket: WebSocket, data: Data?)
}
open class WebSocket : NSObject, StreamDelegate {
enum OpCode : UInt8 {
case continueFrame = 0x0
case textFrame = 0x1
case binaryFrame = 0x2
// 3-7 are reserved.
case connectionClose = 0x8
case ping = 0x9
case pong = 0xA
// B-F reserved.
}
public enum CloseCode : UInt16 {
case normal = 1000
case goingAway = 1001
case protocolError = 1002
case protocolUnhandledType = 1003
// 1004 reserved.
case noStatusReceived = 1005
//1006 reserved.
case encoding = 1007
case policyViolated = 1008
case messageTooBig = 1009
}
public static let ErrorDomain = "WebSocket"
enum InternalErrorCode: UInt16 {
// 0-999 WebSocket status codes not used
case outputStreamWriteError = 1
}
// Where the callback is executed. It defaults to the main UI thread queue.
public var callbackQueue = DispatchQueue.main
var optionalProtocols: [String]?
// MARK: - Constants
let headerWSUpgradeName = "Upgrade"
let headerWSUpgradeValue = "websocket"
let headerWSHostName = "Host"
let headerWSConnectionName = "Connection"
let headerWSConnectionValue = "Upgrade"
let headerWSProtocolName = "Sec-WebSocket-Protocol"
let headerWSVersionName = "Sec-WebSocket-Version"
let headerWSVersionValue = "13"
let headerWSKeyName = "Sec-WebSocket-Key"
let headerOriginName = "Origin"
let headerWSAcceptName = "Sec-WebSocket-Accept"
let BUFFER_MAX = 4096
let FinMask: UInt8 = 0x80
let OpCodeMask: UInt8 = 0x0F
let RSVMask: UInt8 = 0x70
let MaskMask: UInt8 = 0x80
let PayloadLenMask: UInt8 = 0x7F
let MaxFrameSize: Int = 32
let httpSwitchProtocolCode = 101
let supportedSSLSchemes = ["wss", "https"]
class WSResponse {
var isFin = false
var code: OpCode = .continueFrame
var bytesLeft = 0
var frameCount = 0
var buffer: NSMutableData?
}
// MARK: - Delegates
/// Responds to callback about new messages coming in over the WebSocket
/// and also connection/disconnect messages.
public weak var delegate: WebSocketDelegate?
/// Receives a callback for each pong message recived.
public weak var pongDelegate: WebSocketPongDelegate?
// MARK: - Block based API.
public var onConnect: ((Void) -> Void)?
public var onDisconnect: ((NSError?) -> Void)?
public var onText: ((String) -> Void)?
public var onData: ((Data) -> Void)?
public var onPong: ((Data?) -> Void)?
public var headers = [String: String]()
public var voipEnabled = false
public var disableSSLCertValidation = false
public var security: SSLTrustValidator?
public var enabledSSLCipherSuites: [SSLCipherSuite]?
public var origin: String?
public var timeout = 5
public var isConnected: Bool {
return connected
}
public var currentURL: URL { return url }
// MARK: - Private
private var url: URL
private var inputStream: InputStream?
private var outputStream: OutputStream?
private var connected = false
private var isConnecting = false
private var writeQueue = OperationQueue()
private var readStack = [WSResponse]()
private var inputQueue = [Data]()
private var fragBuffer: Data?
private var certValidated = false
private var didDisconnect = false
private var readyToWrite = false
private let mutex = NSLock()
private let notificationCenter = NotificationCenter.default
private var canDispatch: Bool {
mutex.lock()
let canWork = readyToWrite
mutex.unlock()
return canWork
}
/// The shared processing queue used for all WebSocket.
private static let sharedWorkQueue = DispatchQueue(label: "com.vluxe.starscream.websocket", attributes: [])
/// Used for setting protocols.
public init(url: URL, protocols: [String]? = nil) {
self.url = url
self.origin = url.absoluteString
if let hostUrl = URL (string: "/", relativeTo: url) {
var origin = hostUrl.absoluteString
origin.remove(at: origin.index(before: origin.endIndex))
self.origin = origin
}
writeQueue.maxConcurrentOperationCount = 1
optionalProtocols = protocols
}
// Used for specifically setting the QOS for the write queue.
public convenience init(url: URL, writeQueueQOS: QualityOfService, protocols: [String]? = nil) {
self.init(url: url, protocols: protocols)
writeQueue.qualityOfService = writeQueueQOS
}
/**
Connect to the WebSocket server on a background thread.
*/
open func connect() {
guard !isConnecting else { return }
didDisconnect = false
isConnecting = true
createHTTPRequest()
}
/**
Disconnect from the server. I send a Close control frame to the server, then expect the server to respond with a Close control frame and close the socket from its end. I notify my delegate once the socket has been closed.
If you supply a non-nil `forceTimeout`, I wait at most that long (in seconds) for the server to close the socket. After the timeout expires, I close the socket and notify my delegate.
If you supply a zero (or negative) `forceTimeout`, I immediately close the socket (without sending a Close control frame) and notify my delegate.
- Parameter forceTimeout: Maximum time to wait for the server to close the socket.
- Parameter closeCode: The code to send on disconnect. The default is the normal close code for cleanly disconnecting a webSocket.
*/
open func disconnect(forceTimeout: TimeInterval? = nil, closeCode: UInt16 = CloseCode.normal.rawValue) {
guard isConnected else { return }
switch forceTimeout {
case .some(let seconds) where seconds > 0:
let milliseconds = Int(seconds * 1_000)
callbackQueue.asyncAfter(deadline: .now() + .milliseconds(milliseconds)) { [weak self] in
self?.disconnectStream(nil)
}
fallthrough
case .none:
writeError(closeCode)
default:
disconnectStream(nil)
break
}
}
/**
Write a string to the websocket. This sends it as a text frame.
If you supply a non-nil completion block, I will perform it when the write completes.
- parameter string: The string to write.
- parameter completion: The (optional) completion handler.
*/
open func write(string: String, completion: (() -> ())? = nil) {
guard isConnected else { return }
dequeueWrite(string.data(using: String.Encoding.utf8)!, code: .textFrame, writeCompletion: completion)
}
/**
Write binary data to the websocket. This sends it as a binary frame.
If you supply a non-nil completion block, I will perform it when the write completes.
- parameter data: The data to write.
- parameter completion: The (optional) completion handler.
*/
open func write(data: Data, completion: (() -> ())? = nil) {
guard isConnected else { return }
dequeueWrite(data, code: .binaryFrame, writeCompletion: completion)
}
/**
Write a ping to the websocket. This sends it as a control frame.
Yodel a sound to the planet. This sends it as an astroid. http://youtu.be/Eu5ZJELRiJ8?t=42s
*/
open func write(ping: Data, completion: (() -> ())? = nil) {
guard isConnected else { return }
dequeueWrite(ping, code: .ping, writeCompletion: completion)
}
/**
Private method that starts the connection.
*/
private func createHTTPRequest() {
let urlRequest = CFHTTPMessageCreateRequest(kCFAllocatorDefault, "GET" as CFString,
url as CFURL, kCFHTTPVersion1_1).takeRetainedValue()
var port = url.port
if port == nil {
if supportedSSLSchemes.contains(url.scheme!) {
port = 443
} else {
port = 80
}
}
addHeader(urlRequest, key: headerWSUpgradeName, val: headerWSUpgradeValue)
addHeader(urlRequest, key: headerWSConnectionName, val: headerWSConnectionValue)
if let protocols = optionalProtocols {
addHeader(urlRequest, key: headerWSProtocolName, val: protocols.joined(separator: ","))
}
addHeader(urlRequest, key: headerWSVersionName, val: headerWSVersionValue)
addHeader(urlRequest, key: headerWSKeyName, val: generateWebSocketKey())
if let origin = origin {
addHeader(urlRequest, key: headerOriginName, val: origin)
}
addHeader(urlRequest, key: headerWSHostName, val: "\(url.host!):\(port!)")
for (key, value) in headers {
addHeader(urlRequest, key: key, val: value)
}
if let cfHTTPMessage = CFHTTPMessageCopySerializedMessage(urlRequest) {
let serializedRequest = cfHTTPMessage.takeRetainedValue()
initStreamsWithData(serializedRequest as Data, Int(port!))
}
}
/**
Add a header to the CFHTTPMessage by using the NSString bridges to CFString
*/
private func addHeader(_ urlRequest: CFHTTPMessage, key: String, val: String) {
CFHTTPMessageSetHeaderFieldValue(urlRequest, key as CFString, val as CFString)
}
/**
Generate a WebSocket key as needed in RFC.
*/
private func generateWebSocketKey() -> String {
var key = ""
let seed = 16
for _ in 0..<seed {
let uni = UnicodeScalar(UInt32(97 + arc4random_uniform(25)))
key += "\(Character(uni!))"
}
let data = key.data(using: String.Encoding.utf8)
let baseKey = data?.base64EncodedString(options: NSData.Base64EncodingOptions(rawValue: 0))
return baseKey!
}
/**
Start the stream connection and write the data to the output stream.
*/
private func initStreamsWithData(_ data: Data, _ port: Int) {
//higher level API we will cut over to at some point
//NSStream.getStreamsToHostWithName(url.host, port: url.port.integerValue, inputStream: &inputStream, outputStream: &outputStream)
// Disconnect and clean up any existing streams before setting up a new pair
disconnectStream(nil, runDelegate: false)
var readStream: Unmanaged<CFReadStream>?
var writeStream: Unmanaged<CFWriteStream>?
let h = url.host! as NSString
CFStreamCreatePairWithSocketToHost(nil, h, UInt32(port), &readStream, &writeStream)
inputStream = readStream!.takeRetainedValue()
outputStream = writeStream!.takeRetainedValue()
guard let inStream = inputStream, let outStream = outputStream else { return }
inStream.delegate = self
outStream.delegate = self
if supportedSSLSchemes.contains(url.scheme!) {
inStream.setProperty(StreamSocketSecurityLevel.negotiatedSSL as AnyObject, forKey: Stream.PropertyKey.socketSecurityLevelKey)
outStream.setProperty(StreamSocketSecurityLevel.negotiatedSSL as AnyObject, forKey: Stream.PropertyKey.socketSecurityLevelKey)
if disableSSLCertValidation {
let settings: [NSObject: NSObject] = [kCFStreamSSLValidatesCertificateChain: NSNumber(value: false), kCFStreamSSLPeerName: kCFNull]
inStream.setProperty(settings, forKey: kCFStreamPropertySSLSettings as Stream.PropertyKey)
outStream.setProperty(settings, forKey: kCFStreamPropertySSLSettings as Stream.PropertyKey)
}
if let cipherSuites = self.enabledSSLCipherSuites {
if let sslContextIn = CFReadStreamCopyProperty(inputStream, CFStreamPropertyKey(rawValue: kCFStreamPropertySSLContext)) as! SSLContext?,
let sslContextOut = CFWriteStreamCopyProperty(outputStream, CFStreamPropertyKey(rawValue: kCFStreamPropertySSLContext)) as! SSLContext? {
let resIn = SSLSetEnabledCiphers(sslContextIn, cipherSuites, cipherSuites.count)
let resOut = SSLSetEnabledCiphers(sslContextOut, cipherSuites, cipherSuites.count)
if resIn != errSecSuccess {
let error = self.errorWithDetail("Error setting ingoing cypher suites", code: UInt16(resIn))
disconnectStream(error)
return
}
if resOut != errSecSuccess {
let error = self.errorWithDetail("Error setting outgoing cypher suites", code: UInt16(resOut))
disconnectStream(error)
return
}
}
}
} else {
certValidated = true //not a https session, so no need to check SSL pinning
}
if voipEnabled {
inStream.setProperty(StreamNetworkServiceTypeValue.voIP as AnyObject, forKey: Stream.PropertyKey.networkServiceType)
outStream.setProperty(StreamNetworkServiceTypeValue.voIP as AnyObject, forKey: Stream.PropertyKey.networkServiceType)
}
CFReadStreamSetDispatchQueue(inStream, WebSocket.sharedWorkQueue)
CFWriteStreamSetDispatchQueue(outStream, WebSocket.sharedWorkQueue)
inStream.open()
outStream.open()
self.mutex.lock()
self.readyToWrite = true
self.mutex.unlock()
let bytes = UnsafeRawPointer((data as NSData).bytes).assumingMemoryBound(to: UInt8.self)
var out = timeout * 1_000_000 // wait 5 seconds before giving up
let operation = BlockOperation()
operation.addExecutionBlock { [weak self, weak operation] in
guard let sOperation = operation else { return }
while !outStream.hasSpaceAvailable && !sOperation.isCancelled {
usleep(100) // wait until the socket is ready
guard !sOperation.isCancelled else { return }
out -= 100
if out < 0 {
WebSocket.sharedWorkQueue.async {
self?.cleanupStream()
}
self?.doDisconnect(self?.errorWithDetail("write wait timed out", code: 2))
return
} else if outStream.streamError != nil {
return // disconnectStream will be called.
}
}
guard !sOperation.isCancelled, let s = self else { return }
// Do the pinning now if needed
if let sec = s.security, !s.certValidated {
let trust = outStream.property(forKey: kCFStreamPropertySSLPeerTrust as Stream.PropertyKey) as! SecTrust
let domain = outStream.property(forKey: kCFStreamSSLPeerName as Stream.PropertyKey) as? String
s.certValidated = sec.isValid(trust, domain: domain)
if !s.certValidated {
WebSocket.sharedWorkQueue.async {
let error = s.errorWithDetail("Invalid SSL certificate", code: 1)
s.disconnectStream(error)
}
return
}
}
outStream.write(bytes, maxLength: data.count)
}
writeQueue.addOperation(operation)
}
/**
Delegate for the stream methods. Processes incoming bytes
*/
open func stream(_ aStream: Stream, handle eventCode: Stream.Event) {
if eventCode == .hasBytesAvailable {
if aStream == inputStream {
processInputStream()
}
} else if eventCode == .errorOccurred {
disconnectStream(aStream.streamError as NSError?)
} else if eventCode == .endEncountered {
disconnectStream(nil)
}
}
/**
Disconnect the stream object and notifies the delegate.
*/
private func disconnectStream(_ error: NSError?, runDelegate: Bool = true) {
if error == nil {
writeQueue.waitUntilAllOperationsAreFinished()
} else {
writeQueue.cancelAllOperations()
}
cleanupStream()
connected = false
if runDelegate {
doDisconnect(error)
}
}
/**
cleanup the streams.
*/
private func cleanupStream() {
outputStream?.delegate = nil
inputStream?.delegate = nil
if let stream = inputStream {
CFReadStreamSetDispatchQueue(stream, nil)
stream.close()
}
if let stream = outputStream {
CFWriteStreamSetDispatchQueue(stream, nil)
stream.close()
}
outputStream = nil
inputStream = nil
fragBuffer = nil
}
/**
Handles the incoming bytes and sending them to the proper processing method.
*/
private func processInputStream() {
let buf = NSMutableData(capacity: BUFFER_MAX)
let buffer = UnsafeMutableRawPointer(mutating: buf!.bytes).assumingMemoryBound(to: UInt8.self)
let length = inputStream!.read(buffer, maxLength: BUFFER_MAX)
guard length > 0 else { return }
var process = false
if inputQueue.count == 0 {
process = true
}
inputQueue.append(Data(bytes: buffer, count: length))
if process {
dequeueInput()
}
}
/**
Dequeue the incoming input so it is processed in order.
*/
private func dequeueInput() {
while !inputQueue.isEmpty {
autoreleasepool {
let data = inputQueue[0]
var work = data
if let buffer = fragBuffer {
var combine = NSData(data: buffer) as Data
combine.append(data)
work = combine
fragBuffer = nil
}
let buffer = UnsafeRawPointer((work as NSData).bytes).assumingMemoryBound(to: UInt8.self)
let length = work.count
if !connected {
processTCPHandshake(buffer, bufferLen: length)
} else {
processRawMessagesInBuffer(buffer, bufferLen: length)
}
inputQueue = inputQueue.filter{ $0 != data }
}
}
}
/**
Handle checking the inital connection status
*/
private func processTCPHandshake(_ buffer: UnsafePointer<UInt8>, bufferLen: Int) {
let code = processHTTP(buffer, bufferLen: bufferLen)
switch code {
case 0:
break
case -1:
fragBuffer = Data(bytes: buffer, count: bufferLen)
break // do nothing, we are going to collect more data
default:
doDisconnect(errorWithDetail("Invalid HTTP upgrade", code: UInt16(code)))
}
}
/**
Finds the HTTP Packet in the TCP stream, by looking for the CRLF.
*/
private func processHTTP(_ buffer: UnsafePointer<UInt8>, bufferLen: Int) -> Int {
let CRLFBytes = [UInt8(ascii: "\r"), UInt8(ascii: "\n"), UInt8(ascii: "\r"), UInt8(ascii: "\n")]
var k = 0
var totalSize = 0
for i in 0..<bufferLen {
if buffer[i] == CRLFBytes[k] {
k += 1
if k == 3 {
totalSize = i + 1
break
}
} else {
k = 0
}
}
if totalSize > 0 {
let code = validateResponse(buffer, bufferLen: totalSize)
if code != 0 {
return code
}
isConnecting = false
connected = true
didDisconnect = false
if canDispatch {
callbackQueue.async { [weak self] in
guard let s = self else { return }
s.onConnect?()
s.delegate?.websocketDidConnect(socket: s)
s.notificationCenter.post(name: NSNotification.Name(WebsocketDidConnectNotification), object: self)
}
}
totalSize += 1 //skip the last \n
let restSize = bufferLen - totalSize
if restSize > 0 {
processRawMessagesInBuffer(buffer + totalSize, bufferLen: restSize)
}
return 0 //success
}
return -1 // Was unable to find the full TCP header.
}
/**
Validates the HTTP is a 101 as per the RFC spec.
*/
private func validateResponse(_ buffer: UnsafePointer<UInt8>, bufferLen: Int) -> Int {
let response = CFHTTPMessageCreateEmpty(kCFAllocatorDefault, false).takeRetainedValue()
CFHTTPMessageAppendBytes(response, buffer, bufferLen)
let code = CFHTTPMessageGetResponseStatusCode(response)
if code != httpSwitchProtocolCode {
return code
}
if let cfHeaders = CFHTTPMessageCopyAllHeaderFields(response) {
let headers = cfHeaders.takeRetainedValue() as NSDictionary
if let acceptKey = headers[headerWSAcceptName as NSString] as? NSString {
if acceptKey.length > 0 {
return 0
}
}
}
return -1
}
/**
Read a 16 bit big endian value from a buffer
*/
private static func readUint16(_ buffer: UnsafePointer<UInt8>, offset: Int) -> UInt16 {
return (UInt16(buffer[offset + 0]) << 8) | UInt16(buffer[offset + 1])
}
/**
Read a 64 bit big endian value from a buffer
*/
private static func readUint64(_ buffer: UnsafePointer<UInt8>, offset: Int) -> UInt64 {
var value = UInt64(0)
for i in 0...7 {
value = (value << 8) | UInt64(buffer[offset + i])
}
return value
}
/**
Write a 16-bit big endian value to a buffer.
*/
private static func writeUint16(_ buffer: UnsafeMutablePointer<UInt8>, offset: Int, value: UInt16) {
buffer[offset + 0] = UInt8(value >> 8)
buffer[offset + 1] = UInt8(value & 0xff)
}
/**
Write a 64-bit big endian value to a buffer.
*/
private static func writeUint64(_ buffer: UnsafeMutablePointer<UInt8>, offset: Int, value: UInt64) {
for i in 0...7 {
buffer[offset + i] = UInt8((value >> (8*UInt64(7 - i))) & 0xff)
}
}
/**
Process one message at the start of `buffer`. Return another buffer (sharing storage) that contains the leftover contents of `buffer` that I didn't process.
*/
private func processOneRawMessage(inBuffer buffer: UnsafeBufferPointer<UInt8>) -> UnsafeBufferPointer<UInt8> {
let response = readStack.last
guard let baseAddress = buffer.baseAddress else {return emptyBuffer}
let bufferLen = buffer.count
if response != nil && bufferLen < 2 {
fragBuffer = Data(buffer: buffer)
return emptyBuffer
}
if let response = response, response.bytesLeft > 0 {
var len = response.bytesLeft
var extra = bufferLen - response.bytesLeft
if response.bytesLeft > bufferLen {
len = bufferLen
extra = 0
}
response.bytesLeft -= len
response.buffer?.append(Data(bytes: baseAddress, count: len))
_ = processResponse(response)
return buffer.fromOffset(bufferLen - extra)
} else {
let isFin = (FinMask & baseAddress[0])
let receivedOpcode = OpCode(rawValue: (OpCodeMask & baseAddress[0]))
let isMasked = (MaskMask & baseAddress[1])
let payloadLen = (PayloadLenMask & baseAddress[1])
var offset = 2
if (isMasked > 0 || (RSVMask & baseAddress[0]) > 0) && receivedOpcode != .pong {
let errCode = CloseCode.protocolError.rawValue
doDisconnect(errorWithDetail("masked and rsv data is not currently supported", code: errCode))
writeError(errCode)
return emptyBuffer
}
let isControlFrame = (receivedOpcode == .connectionClose || receivedOpcode == .ping)
if !isControlFrame && (receivedOpcode != .binaryFrame && receivedOpcode != .continueFrame &&
receivedOpcode != .textFrame && receivedOpcode != .pong) {
let errCode = CloseCode.protocolError.rawValue
doDisconnect(errorWithDetail("unknown opcode: \(String(describing: receivedOpcode))", code: errCode))
writeError(errCode)
return emptyBuffer
}
if isControlFrame && isFin == 0 {
let errCode = CloseCode.protocolError.rawValue
doDisconnect(errorWithDetail("control frames can't be fragmented", code: errCode))
writeError(errCode)
return emptyBuffer
}
var closeCode = CloseCode.normal.rawValue
if receivedOpcode == .connectionClose {
if payloadLen == 1 {
closeCode = CloseCode.protocolError.rawValue
} else if payloadLen > 1 {
closeCode = WebSocket.readUint16(baseAddress, offset: offset)
if closeCode < 1000 || (closeCode > 1003 && closeCode < 1007) || (closeCode > 1011 && closeCode < 3000) {
closeCode = CloseCode.protocolError.rawValue
}
}
if payloadLen < 2 {
doDisconnect(errorWithDetail("connection closed by server", code: closeCode))
writeError(closeCode)
return emptyBuffer
}
} else if isControlFrame && payloadLen > 125 {
writeError(CloseCode.protocolError.rawValue)
return emptyBuffer
}
var dataLength = UInt64(payloadLen)
if dataLength == 127 {
dataLength = WebSocket.readUint64(baseAddress, offset: offset)
offset += MemoryLayout<UInt64>.size
} else if dataLength == 126 {
dataLength = UInt64(WebSocket.readUint16(baseAddress, offset: offset))
offset += MemoryLayout<UInt16>.size
}
if bufferLen < offset || UInt64(bufferLen - offset) < dataLength {
fragBuffer = Data(bytes: baseAddress, count: bufferLen)
return emptyBuffer
}
var len = dataLength
if dataLength > UInt64(bufferLen) {
len = UInt64(bufferLen-offset)
}
let data: Data
if len < 0 {
len = 0
data = Data()
} else {
if receivedOpcode == .connectionClose && len > 0 {
let size = MemoryLayout<UInt16>.size
offset += size
len -= UInt64(size)
}
data = Data(bytes: baseAddress+offset, count: Int(len))
}
if receivedOpcode == .connectionClose {
var closeReason = "connection closed by server"
if let customCloseReason = String(data: data, encoding: .utf8) {
closeReason = customCloseReason
} else {
closeCode = CloseCode.protocolError.rawValue
}
doDisconnect(errorWithDetail(closeReason, code: closeCode))
writeError(closeCode)
return emptyBuffer
}
if receivedOpcode == .pong {
if canDispatch {
callbackQueue.async { [weak self] in
guard let s = self else { return }
let pongData: Data? = data.count > 0 ? data : nil
s.onPong?(pongData)
s.pongDelegate?.websocketDidReceivePong(socket: s, data: pongData)
}
}
return buffer.fromOffset(offset + Int(len))
}
var response = readStack.last
if isControlFrame {
response = nil // Don't append pings.
}
if isFin == 0 && receivedOpcode == .continueFrame && response == nil {
let errCode = CloseCode.protocolError.rawValue
doDisconnect(errorWithDetail("continue frame before a binary or text frame", code: errCode))
writeError(errCode)
return emptyBuffer
}
var isNew = false
if response == nil {
if receivedOpcode == .continueFrame {
let errCode = CloseCode.protocolError.rawValue
doDisconnect(errorWithDetail("first frame can't be a continue frame",
code: errCode))
writeError(errCode)
return emptyBuffer
}
isNew = true
response = WSResponse()
response!.code = receivedOpcode!
response!.bytesLeft = Int(dataLength)
response!.buffer = NSMutableData(data: data)
} else {
if receivedOpcode == .continueFrame {
response!.bytesLeft = Int(dataLength)
} else {
let errCode = CloseCode.protocolError.rawValue
doDisconnect(errorWithDetail("second and beyond of fragment message must be a continue frame",
code: errCode))
writeError(errCode)
return emptyBuffer
}
response!.buffer!.append(data)
}
if let response = response {
response.bytesLeft -= Int(len)
response.frameCount += 1
response.isFin = isFin > 0 ? true : false
if isNew {
readStack.append(response)
}
_ = processResponse(response)
}
let step = Int(offset + numericCast(len))
return buffer.fromOffset(step)
}
}
/**
Process all messages in the buffer if possible.
*/
private func processRawMessagesInBuffer(_ pointer: UnsafePointer<UInt8>, bufferLen: Int) {
var buffer = UnsafeBufferPointer(start: pointer, count: bufferLen)
repeat {
buffer = processOneRawMessage(inBuffer: buffer)
} while buffer.count >= 2
if buffer.count > 0 {
fragBuffer = Data(buffer: buffer)
}
}
/**
Process the finished response of a buffer.
*/
private func processResponse(_ response: WSResponse) -> Bool {
if response.isFin && response.bytesLeft <= 0 {
if response.code == .ping {
let data = response.buffer! // local copy so it is perverse for writing
dequeueWrite(data as Data, code: .pong)
} else if response.code == .textFrame {
let str: NSString? = NSString(data: response.buffer! as Data, encoding: String.Encoding.utf8.rawValue)
if str == nil {
writeError(CloseCode.encoding.rawValue)
return false
}
if canDispatch {
callbackQueue.async { [weak self] in
guard let s = self else { return }
s.onText?(str! as String)
s.delegate?.websocketDidReceiveMessage(socket: s, text: str! as String)
}
}
} else if response.code == .binaryFrame {
if canDispatch {
let data = response.buffer! // local copy so it is perverse for writing
callbackQueue.async { [weak self] in
guard let s = self else { return }
s.onData?(data as Data)
s.delegate?.websocketDidReceiveData(socket: s, data: data as Data)
}
}
}
readStack.removeLast()
return true
}
return false
}
/**
Create an error
*/
private func errorWithDetail(_ detail: String, code: UInt16) -> NSError {
var details = [String: String]()
details[NSLocalizedDescriptionKey] = detail
return NSError(domain: WebSocket.ErrorDomain, code: Int(code), userInfo: details)
}
/**
Write an error to the socket
*/
private func writeError(_ code: UInt16) {
let buf = NSMutableData(capacity: MemoryLayout<UInt16>.size)
let buffer = UnsafeMutableRawPointer(mutating: buf!.bytes).assumingMemoryBound(to: UInt8.self)
WebSocket.writeUint16(buffer, offset: 0, value: code)
dequeueWrite(Data(bytes: buffer, count: MemoryLayout<UInt16>.size), code: .connectionClose)
}
/**
Used to write things to the stream
*/
private func dequeueWrite(_ data: Data, code: OpCode, writeCompletion: (() -> ())? = nil) {
let operation = BlockOperation()
operation.addExecutionBlock { [weak self, weak operation] in
//stream isn't ready, let's wait
guard let s = self else { return }
guard let sOperation = operation else { return }
var offset = 2
let dataLength = data.count
let frame = NSMutableData(capacity: dataLength + s.MaxFrameSize)
let buffer = UnsafeMutableRawPointer(frame!.mutableBytes).assumingMemoryBound(to: UInt8.self)
buffer[0] = s.FinMask | code.rawValue
if dataLength < 126 {
buffer[1] = CUnsignedChar(dataLength)
} else if dataLength <= Int(UInt16.max) {
buffer[1] = 126
WebSocket.writeUint16(buffer, offset: offset, value: UInt16(dataLength))
offset += MemoryLayout<UInt16>.size
} else {
buffer[1] = 127
WebSocket.writeUint64(buffer, offset: offset, value: UInt64(dataLength))
offset += MemoryLayout<UInt64>.size
}
buffer[1] |= s.MaskMask
let maskKey = UnsafeMutablePointer<UInt8>(buffer + offset)
_ = SecRandomCopyBytes(kSecRandomDefault, Int(MemoryLayout<UInt32>.size), maskKey)
offset += MemoryLayout<UInt32>.size
for i in 0..<dataLength {
buffer[offset] = data[i] ^ maskKey[i % MemoryLayout<UInt32>.size]
offset += 1
}
var total = 0
while !sOperation.isCancelled {
guard let outStream = s.outputStream else { break }
let writeBuffer = UnsafeRawPointer(frame!.bytes+total).assumingMemoryBound(to: UInt8.self)
let len = outStream.write(writeBuffer, maxLength: offset-total)
if len < 0 {
var error: Error?
if let streamError = outStream.streamError {
error = streamError
} else {
let errCode = InternalErrorCode.outputStreamWriteError.rawValue
error = s.errorWithDetail("output stream error during write", code: errCode)
}
s.doDisconnect(error as NSError?)
break
} else {
total += len
}
if total >= offset {
if let queue = self?.callbackQueue, let callback = writeCompletion {
queue.async {
callback()
}
}
break
}
}
}
writeQueue.addOperation(operation)
}
/**
Used to preform the disconnect delegate
*/
private func doDisconnect(_ error: NSError?) {
guard !didDisconnect else { return }
didDisconnect = true
isConnecting = false
connected = false
guard canDispatch else {return}
callbackQueue.async { [weak self] in
guard let s = self else { return }
s.onDisconnect?(error)
s.delegate?.websocketDidDisconnect(socket: s, error: error)
let userInfo = error.map{ [WebsocketDisconnectionErrorKeyName: $0] }
s.notificationCenter.post(name: NSNotification.Name(WebsocketDidDisconnectNotification), object: self, userInfo: userInfo)
}
}
// MARK: - Deinit
deinit {
mutex.lock()
readyToWrite = false
mutex.unlock()
cleanupStream()
writeQueue.cancelAllOperations()
}
}
private extension Data {
init(buffer: UnsafeBufferPointer<UInt8>) {
self.init(bytes: buffer.baseAddress!, count: buffer.count)
}
}
private extension UnsafeBufferPointer {
func fromOffset(_ offset: Int) -> UnsafeBufferPointer<Element> {
return UnsafeBufferPointer<Element>(start: baseAddress?.advanced(by: offset), count: count - offset)
}
}
private let emptyBuffer = UnsafeBufferPointer<UInt8>(start: nil, count: 0)