KancolleSniffer/HttpProxy.cs

   1 // Copyright (c) 2015 Kazuhiro Fujieda <fujieda@users.osdn.me>\r
   2 //\r
   3 // Licensed under the Apache License, Version 2.0 (the "License");\r
   4 // you may not use this file except in compliance with the License.\r
   5 // You may obtain a copy of the License at\r
   6 //\r
   7 //    http://www.apache.org/licenses/LICENSE-2.0\r
   8 //\r
   9 // Unless required by applicable law or agreed to in writing, software\r
  10 // distributed under the License is distributed on an "AS IS" BASIS,\r
  11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.\r
  12 // See the License for the specific language governing permissions and\r
  13 // limitations under the License.\r
  14 \r
  15 using System;\r
  16 using System.Globalization;\r
  17 using System.IO;\r
  18 using System.IO.Compression;\r
  19 using System.Net;\r
  20 using System.Net.Sockets;\r
  21 using System.Text;\r
  22 using System.Text.RegularExpressions;\r
  23 using System.Threading.Tasks;\r
  24 \r
  25 namespace KancolleSniffer\r
  26 {\r
  27     public class HttpProxy\r
  28     {\r
  29         private static HttpProxy _httpProxy;\r
  30         public static int LocalPort { get; set; }\r
  31         public static string UpstreamProxyHost { get; set; }\r
  32         public static int UpstreamProxyPort { get; set; }\r
  33         public static bool IsEnableUpstreamProxy { get; set; }\r
  34         public static bool IsInListening { get; private set; }\r
  35         public static event Action<Session> AfterSessionComplete;\r
  36 \r
  37         private TcpListener _listener;\r
  38 \r
  39         public static void Startup(int port, bool dummy0, bool dummy1)\r
  40         {\r
  41             LocalPort = port;\r
  42             _httpProxy = new HttpProxy();\r
  43             _httpProxy.Start();\r
  44         }\r
  45 \r
  46         public void Start()\r
  47         {\r
  48             _listener = new TcpListener(IPAddress.Loopback, LocalPort);\r
  49             _listener.Start();\r
  50             LocalPort = ((IPEndPoint)_listener.LocalEndpoint).Port;\r
  51             IsInListening = true;\r
  52             Task.Run(() => AcceptClient());\r
  53         }\r
  54 \r
  55         public static void Shutdown()\r
  56         {\r
  57             _httpProxy?.Stop();\r
  58         }\r
  59 \r
  60         public void Stop()\r
  61         {\r
  62             IsInListening = false;\r
  63             _listener.Server.Close();\r
  64             _listener.Stop();\r
  65         }\r
  66 \r
  67         public void AcceptClient()\r
  68         {\r
  69             try\r
  70             {\r
  71                 while (true)\r
  72                 {\r
  73                     var client = _listener.AcceptSocket();\r
  74                     Task.Run(() => new HttpClient(client).ProcessRequest());\r
  75                 }\r
  76             }\r
  77             catch (SocketException)\r
  78             {\r
  79             }\r
  80             finally\r
  81             {\r
  82                 Stop();\r
  83             }\r
  84         }\r
  85 \r
  86         private class HttpClient\r
  87         {\r
  88             private readonly Socket _client;\r
  89             private Socket _server;\r
  90             private readonly Session _session;\r
  91             private readonly HttpStream _clientStream;\r
  92             private HttpStream _serverStream;\r
  93 \r
  94             public HttpClient(Socket client)\r
  95             {\r
  96                 _client = client;\r
  97                 _clientStream = new HttpStream(client);\r
  98                 _session = new Session();\r
  99             }\r
 100 \r
 101             public void ProcessRequest()\r
 102             {\r
 103                 try\r
 104                 {\r
 105                     ReceiveRequest();\r
 106                     if (_session.Request.Method == "CONNECT")\r
 107                     {\r
 108                         HandleConnect();\r
 109                         return;\r
 110                     }\r
 111                     if (_session.Request.Host.StartsWith("localhost"))\r
 112                     {\r
 113                         LogServer.Process(_client, _session.Request.RequestLine);\r
 114                         return;\r
 115                     }\r
 116                     SendRequest();\r
 117                     ReceiveRequestBody();\r
 118                     SendRequestBody();\r
 119                     ReceiveResponse();\r
 120                     SendResponse();\r
 121                     Close();\r
 122                     AfterSessionComplete?.Invoke(_session);\r
 123                 }\r
 124                 catch (Exception e)\r
 125                 {\r
 126                     File.AppendAllText("debug.log", $"[{DateTime.Now.ToString("g")}] " + e + "\r\n");\r
 127                 }\r
 128                 finally\r
 129                 {\r
 130                     Close();\r
 131                 }\r
 132             }\r
 133 \r
 134             private void ReceiveRequest()\r
 135             {\r
 136                 var requestLine = _clientStream.ReadLine();\r
 137                 _session.Request.RequestLine = requestLine;\r
 138                 _session.Request.Headers = _clientStream.ReadHeaders();\r
 139             }\r
 140 \r
 141             private void ReceiveRequestBody()\r
 142             {\r
 143                 if (_session.Request.ContentLength != -1 || _session.Request.TransferEncoding != null)\r
 144                     _session.Request.ReadBody(_clientStream);\r
 145             }\r
 146 \r
 147             private void SendRequest()\r
 148             {\r
 149                 _server = ConnectServer();\r
 150                 _serverStream = new HttpStream(_server).\r
 151                     WriteLines(_session.Request.RequestLine + _session.Request.ModifiedHeaders);\r
 152             }\r
 153 \r
 154             private void SendRequestBody()\r
 155             {\r
 156                 _serverStream.Write(_session.Request.Body);\r
 157             }\r
 158 \r
 159             private void ReceiveResponse()\r
 160             {\r
 161                 _session.Response.StatusLine = _serverStream.ReadLine();\r
 162                 _session.Response.Headers = _serverStream.ReadHeaders();\r
 163                 if (HasBody)\r
 164                     _session.Response.ReadBody(_serverStream);\r
 165             }\r
 166 \r
 167             private bool HasBody\r
 168             {\r
 169                 get\r
 170                 {\r
 171                     var code = _session.Response.StatusCode;\r
 172                     return (!(_session.Request.Method == "HEAD" ||\r
 173                               code.StartsWith("1") || code == "204" || code == "304"));\r
 174                 }\r
 175             }\r
 176 \r
 177             private void SendResponse()\r
 178             {\r
 179                 _clientStream.WriteLines(_session.Response.StatusLine + _session.Response.ModifiedHeaders)\r
 180                     .Write(_session.Response.Body);\r
 181             }\r
 182 \r
 183             private void HandleConnect()\r
 184             {\r
 185                 var host = "";\r
 186                 var port = 443;\r
 187                 if (!ParseAuthority(_session.Request.PathAndQuery, ref host, ref port))\r
 188                     return;\r
 189                 _server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);\r
 190                 _server.Connect(host, port);\r
 191                 _clientStream.WriteLines("HTTP/1.0 200 Connection established\r\n\r\n");\r
 192                 Task[] tasks =\r
 193                 {\r
 194                     Task.Run(() => { TunnnelSockets(_client, _server); }),\r
 195                     Task.Run(() => { TunnnelSockets(_server, _client); })\r
 196                 };\r
 197                 Task.WaitAll(tasks);\r
 198             }\r
 199 \r
 200             private void TunnnelSockets(Socket from, Socket to)\r
 201             {\r
 202                 try\r
 203                 {\r
 204                     var buf = new byte[8192];\r
 205                     while (true)\r
 206                     {\r
 207                         var n = from.Receive(buf);\r
 208                         if (n == 0)\r
 209                             break;\r
 210                         var sent = to.Send(buf, n, SocketFlags.None);\r
 211                         if (sent < n)\r
 212                             break;\r
 213                     }\r
 214                     to.Shutdown(SocketShutdown.Send);\r
 215                 }\r
 216                 catch (SocketException)\r
 217                 {\r
 218                 }\r
 219             }\r
 220 \r
 221             private static readonly Regex HostAndPortRegex =\r
 222                 new Regex("http://([^:/]+)(?::(\\d+))?/", RegexOptions.Compiled);\r
 223 \r
 224             private Socket ConnectServer()\r
 225             {\r
 226                 string host = null;\r
 227                 var port = 80;\r
 228                 if (IsEnableUpstreamProxy)\r
 229                 {\r
 230                     host = UpstreamProxyHost;\r
 231                     port = UpstreamProxyPort;\r
 232                     goto connect;\r
 233                 }\r
 234                 var m = HostAndPortRegex.Match(_session.Request.RequestLine);\r
 235                 if (m.Success)\r
 236                 {\r
 237                     host = m.Groups[1].Value;\r
 238                     if (m.Groups[2].Success)\r
 239                         port = int.Parse(m.Groups[2].Value);\r
 240                     _session.Request.RequestLine = _session.Request.RequestLine.Remove(m.Index, m.Length - 1);\r
 241                 }\r
 242                 if (host == null && !ParseAuthority(_session.Request.Host, ref host, ref port))\r
 243                     throw new HttpProxyAbort("Can't find destination host");\r
 244                 connect:\r
 245                 var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);\r
 246                 socket.Connect(host, port);\r
 247                 return socket;\r
 248             }\r
 249 \r
 250             private static readonly Regex AuthorityRegex = new Regex("([^:]+)(?::(\\d+))?");\r
 251 \r
 252             private bool ParseAuthority(string authority, ref string host, ref int port)\r
 253             {\r
 254                 if (string.IsNullOrEmpty(authority))\r
 255                     return false;\r
 256                 var m = AuthorityRegex.Match(authority);\r
 257                 if (!m.Success)\r
 258                     return false;\r
 259                 host = m.Groups[1].Value;\r
 260                 if (m.Groups[2].Success)\r
 261                     port = int.Parse(m.Groups[2].Value);\r
 262                 return true;\r
 263             }\r
 264 \r
 265             private void Close()\r
 266             {\r
 267                 _serverStream?.Close();\r
 268                 _clientStream?.Close();\r
 269                 _server?.Close();\r
 270                 _client.Close();\r
 271             }\r
 272         }\r
 273 \r
 274         public class Session\r
 275         {\r
 276             public Request Request { get; set; } = new Request();\r
 277             public Response Response { get; set; } = new Response();\r
 278         }\r
 279 \r
 280         public class Message\r
 281         {\r
 282             private string _headers;\r
 283             public byte[] Body { get; set; }\r
 284 \r
 285             private static readonly Regex CharsetRegx = new Regex("charset=([\\w-]+)",\r
 286                 RegexOptions.Compiled | RegexOptions.IgnoreCase | RegexOptions.CultureInvariant);\r
 287 \r
 288             public int ContentLength { get; set; } = -1;\r
 289             public string TransferEncoding { get; set; }\r
 290             public string ContentType { get; set; }\r
 291             public string ContentEncoding { get; set; }\r
 292             public string Host { get; set; }\r
 293 \r
 294             public string Headers\r
 295             {\r
 296                 get { return _headers; }\r
 297                 set\r
 298                 {\r
 299                     _headers = value;\r
 300                     SetHeaders(_headers);\r
 301                 }\r
 302             }\r
 303 \r
 304             public virtual string ModifiedHeaders => SetConnectionClose(Headers);\r
 305 \r
 306             private string SetConnectionClose(string headers)\r
 307             {\r
 308                 return InsertHeader(RemoveHeaders(headers,\r
 309                     new[] {"connection", "keep-alive", "proxy-connection"}), "Connection: close\r\n");\r
 310             }\r
 311 \r
 312             protected string RemoveHeaders(string headers, string[] fields)\r
 313             {\r
 314                 foreach (var f in fields)\r
 315                 {\r
 316                     var m = MatchField(f, headers);\r
 317                     if (!m.Success)\r
 318                         continue;\r
 319                     headers = headers.Remove(m.Index, m.Length);\r
 320                 }\r
 321                 return headers;\r
 322             }\r
 323 \r
 324             protected string InsertHeader(string headers, string header)\r
 325             {\r
 326                 return headers.Insert(headers.Length - 2, header);\r
 327             }\r
 328 \r
 329             protected virtual void SetHeaders(string headers)\r
 330             {\r
 331                 var s = GetField("content-length");\r
 332                 if (s != null)\r
 333                 {\r
 334                     int len;\r
 335                     ContentLength = int.TryParse(s, out len) ? len : -1;\r
 336                 }\r
 337                 TransferEncoding = GetField("transfer-encoding")?.ToLower(CultureInfo.InvariantCulture);\r
 338                 ContentType = GetField("content-type");\r
 339                 ContentEncoding = GetField("content-encoding");\r
 340                 Host = GetField("host");\r
 341             }\r
 342 \r
 343             protected Match MatchField(string name, string headers)\r
 344             {\r
 345                 var regex = new Regex("^" + name + ":\\s*([^\r]+)\r\n",\r
 346                     RegexOptions.CultureInvariant | RegexOptions.IgnoreCase | RegexOptions.Multiline);\r
 347                 return regex.Match(headers);\r
 348             }\r
 349 \r
 350             protected string GetField(string name)\r
 351             {\r
 352                 var m = MatchField(name, Headers);\r
 353                 return m.Success ? m.Groups[1].Value : null;\r
 354             }\r
 355 \r
 356             public string BodyAsString\r
 357             {\r
 358                 get\r
 359                 {\r
 360                     if (Body == null)\r
 361                         return "";\r
 362                     var m = CharsetRegx.Match(ContentType ?? "");\r
 363                     var encoding = Encoding.ASCII;\r
 364                     if (m.Success)\r
 365                     {\r
 366                         var name = m.Groups[1].Value;\r
 367                         if (name == "utf8")\r
 368                             name = "UTF-8";\r
 369                         encoding = Encoding.GetEncoding(name);\r
 370                     }\r
 371                     return encoding.GetString(Body);\r
 372                 }\r
 373             }\r
 374 \r
 375             public void ReadBody(HttpStream stream)\r
 376             {\r
 377                 if (TransferEncoding != null && TransferEncoding.Contains("chunked"))\r
 378                 {\r
 379                     Body = stream.ReadChunked();\r
 380                 }\r
 381                 else if (ContentLength == 0)\r
 382                 {\r
 383                 }\r
 384                 else if (ContentLength > 0)\r
 385                 {\r
 386                     var buf = new byte[ContentLength];\r
 387                     stream.Read(buf, 0, ContentLength);\r
 388                     Body = buf;\r
 389                 }\r
 390                 else\r
 391                 {\r
 392                     Body = stream.ReadToEnd();\r
 393                 }\r
 394                 if (ContentEncoding == null)\r
 395                     return;\r
 396                 var dc = new MemoryStream();\r
 397                 try\r
 398                 {\r
 399                     if (ContentEncoding == "gzip")\r
 400                         new GZipStream(new MemoryStream(Body), CompressionMode.Decompress).CopyTo(dc);\r
 401                     else if (ContentEncoding == "deflate")\r
 402                         new DeflateStream(new MemoryStream(Body), CompressionMode.Decompress).CopyTo(dc);\r
 403                 }\r
 404                 catch (Exception ex)\r
 405                 {\r
 406                     throw new HttpProxyAbort($"Fail to decode {ContentEncoding}: " + ex.Message);\r
 407                 }\r
 408                 Body = dc.ToArray();\r
 409             }\r
 410         }\r
 411 \r
 412         public class Request : Message\r
 413         {\r
 414             private string _requestLine;\r
 415 \r
 416             public string RequestLine\r
 417             {\r
 418                 get { return _requestLine; }\r
 419                 set\r
 420                 {\r
 421                     _requestLine = value;\r
 422                     var f = _requestLine.Split(' ');\r
 423                     if (f.Length < 3)\r
 424                         throw new HttpProxyAbort("Invalid request line");\r
 425                     Method = f[0];\r
 426                     PathAndQuery = f.Length < 2 ? "" : f[1];\r
 427                 }\r
 428             }\r
 429 \r
 430             public string Method { get; private set; }\r
 431             public string PathAndQuery { get; private set; }\r
 432         }\r
 433 \r
 434         public class Response : Message\r
 435         {\r
 436             private string _statusLine;\r
 437 \r
 438             public override string ModifiedHeaders =>\r
 439                 InsertContentLength(RemoveHeaders(base.ModifiedHeaders,\r
 440                     new[] {"transfer-encoding", "content-encoding", "content-length"}));\r
 441 \r
 442             private string InsertContentLength(string headers)\r
 443             {\r
 444                 return Body == null ? headers : InsertHeader(headers, $"Content-Length: {Body.Length}\r\n");\r
 445             }\r
 446 \r
 447             public string StatusLine\r
 448             {\r
 449                 get { return _statusLine; }\r
 450                 set\r
 451                 {\r
 452                     _statusLine = value;\r
 453                     var f = _statusLine.Split(' ');\r
 454                     if (f.Length < 3)\r
 455                         throw new HttpProxyAbort("Invalid status line");\r
 456                     StatusCode = _statusLine.Split(' ')[1];\r
 457                 }\r
 458             }\r
 459 \r
 460             public string StatusCode { get; private set; }\r
 461         }\r
 462 \r
 463         private class HttpProxyAbort : Exception\r
 464         {\r
 465             public HttpProxyAbort(string message) : base(message)\r
 466             {\r
 467             }\r
 468         }\r
 469 \r
 470         public class HttpStream\r
 471         {\r
 472             private readonly Socket _socket;\r
 473             private readonly byte[] _buffer = new byte[4096];\r
 474             private int _available;\r
 475             private int _position;\r
 476 \r
 477             public HttpStream(Socket socket)\r
 478             {\r
 479                 _socket = socket;\r
 480                 socket.NoDelay = true;\r
 481             }\r
 482 \r
 483             public string ReadLine()\r
 484             {\r
 485                 var sb = new StringBuilder();\r
 486                 int ch;\r
 487                 while ((ch = ReadByte()) != -1)\r
 488                 {\r
 489                     sb.Append((char)ch);\r
 490                     if (ch == '\n')\r
 491                         break;\r
 492                 }\r
 493                 return sb.ToString();\r
 494             }\r
 495 \r
 496             private int ReadByte()\r
 497             {\r
 498                 if (_position < _available)\r
 499                     return _buffer[_position++];\r
 500                 _available = _socket.Receive(_buffer, 0, _buffer.Length, SocketFlags.None);\r
 501                 _position = 0;\r
 502                 return _available == 0 ? -1 : _buffer[_position++];\r
 503             }\r
 504 \r
 505             public HttpStream WriteLines(string s)\r
 506             {\r
 507                 var buf = Encoding.ASCII.GetBytes(s);\r
 508                 Write(buf, 0, buf.Length);\r
 509                 return this;\r
 510             }\r
 511 \r
 512             public string ReadHeaders()\r
 513             {\r
 514                 var sb = new StringBuilder();\r
 515                 string line;\r
 516                 do\r
 517                 {\r
 518                     line = ReadLine();\r
 519                     sb.Append(line);\r
 520                 } while (line != "\r\n");\r
 521                 return sb.ToString();\r
 522             }\r
 523 \r
 524             public byte[] ReadChunked()\r
 525             {\r
 526                 var buf = new MemoryStream();\r
 527                 while (true)\r
 528                 {\r
 529                     var size = ReadLine();\r
 530                     if (size.Length < 3)\r
 531                         break;\r
 532                     var ext = size.IndexOf(';');\r
 533                     size = ext == -1 ? size.Substring(0, size.Length - 2) : size.Substring(0, ext);\r
 534                     int val;\r
 535                     if (!int.TryParse(size, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out val))\r
 536                         throw new HttpProxyAbort("Can't parse chunk size: " + size);\r
 537                     if (val == 0)\r
 538                         break;\r
 539                     var chunk = new byte[val];\r
 540                     Read(chunk, 0, chunk.Length);\r
 541                     buf.Write(chunk, 0, chunk.Length);\r
 542                     ReadLine();\r
 543                 }\r
 544                 string line;\r
 545                 do\r
 546                 {\r
 547                     line = ReadLine();\r
 548                 } while (line != "" && line != "\r\n");\r
 549                 return buf.ToArray();\r
 550             }\r
 551 \r
 552             public byte[] ReadToEnd()\r
 553             {\r
 554                 var result = new MemoryStream();\r
 555                 var buf = new byte[4096];\r
 556                 int len;\r
 557                 while ((len = Read(buf, 0, buf.Length)) > 0)\r
 558                     result.Write(buf, 0, len);\r
 559                 return result.ToArray();\r
 560             }\r
 561 \r
 562             public HttpStream Write(byte[] body)\r
 563             {\r
 564                 if (body != null)\r
 565                     Write(body, 0, body.Length);\r
 566                 return this;\r
 567             }\r
 568 \r
 569             public int Read(byte[] buf, int offset, int count)\r
 570             {\r
 571                 var total = 0;\r
 572                 do\r
 573                 {\r
 574                     int n;\r
 575                     if (_position < _available)\r
 576                     {\r
 577                         n = Math.Min(count, _available - _position);\r
 578                         Buffer.BlockCopy(_buffer, _position, buf, 0, n);\r
 579                         _position += n;\r
 580                     }\r
 581                     else\r
 582                     {\r
 583                         n = _socket.Receive(buf, offset, count, SocketFlags.None);\r
 584                         if (n == 0)\r
 585                             return total == 0 ? n : total;\r
 586                     }\r
 587                     count -= n;\r
 588                     offset += n;\r
 589                     total += n;\r
 590                 } while (count > 0);\r
 591                 return total;\r
 592             }\r
 593 \r
 594             public void Write(byte[] buf, int offset, int count)\r
 595             {\r
 596                 do\r
 597                 {\r
 598                     var n = _socket.Send(buf, offset, count, SocketFlags.None);\r
 599                     if (n == 0)\r
 600                         return;\r
 601                     count -= n;\r
 602                     offset += n;\r
 603                 } while (count > 0);\r
 604             }\r
 605 \r
 606             public HttpStream Close()\r
 607             {\r
 608                 _socket.Close();\r
 609                 return this;\r
 610             }\r
 611         }\r
 612     }\r
 613 }