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 == null)\r
 107                         return;\r
 108                     if (_session.Request.Method == "CONNECT")\r
 109                     {\r
 110                         HandleConnect();\r
 111                         return;\r
 112                     }\r
 113                     if (_session.Request.Host.StartsWith("localhost"))\r
 114                     {\r
 115                         LogServer.Process(_client, _session.Request.RequestLine);\r
 116                         return;\r
 117                     }\r
 118                     SendRequest();\r
 119                     ReceiveRequestBody();\r
 120                     SendRequestBody();\r
 121                     ReceiveResponse();\r
 122                     if (_session.Response.StatusCode == null)\r
 123                         return;\r
 124                     SendResponse();\r
 125                     Close();\r
 126                     AfterSessionComplete?.Invoke(_session);\r
 127                 }\r
 128                 catch (Exception e)\r
 129                 {\r
 130                     File.AppendAllText("debug.log", $"[{DateTime.Now:g}] " + e + "\r\n");\r
 131                 }\r
 132                 finally\r
 133                 {\r
 134                     Close();\r
 135                 }\r
 136             }\r
 137 \r
 138             private void ReceiveRequest()\r
 139             {\r
 140                 var requestLine = _clientStream.ReadLine();\r
 141                 if (requestLine == "")\r
 142                     return;\r
 143                 _session.Request.RequestLine = requestLine;\r
 144                 _session.Request.Headers = _clientStream.ReadHeaders();\r
 145             }\r
 146 \r
 147             private void ReceiveRequestBody()\r
 148             {\r
 149                 if (_session.Request.ContentLength != -1 || _session.Request.TransferEncoding != null)\r
 150                     _session.Request.ReadBody(_clientStream);\r
 151             }\r
 152 \r
 153             private void SendRequest()\r
 154             {\r
 155                 _server = ConnectServer();\r
 156                 _serverStream = new HttpStream(_server).\r
 157                     WriteLines(_session.Request.RequestLine + _session.Request.ModifiedHeaders);\r
 158             }\r
 159 \r
 160             private void SendRequestBody()\r
 161             {\r
 162                 _serverStream.Write(_session.Request.Body);\r
 163             }\r
 164 \r
 165             private void ReceiveResponse()\r
 166             {\r
 167                 var statusLine = _serverStream.ReadLine();\r
 168                 if (statusLine == "")\r
 169                     return;\r
 170                 _session.Response.StatusLine = statusLine;\r
 171                 _session.Response.Headers = _serverStream.ReadHeaders();\r
 172                 if (HasBody)\r
 173                     _session.Response.ReadBody(_serverStream);\r
 174             }\r
 175 \r
 176             private bool HasBody\r
 177             {\r
 178                 get\r
 179                 {\r
 180                     var code = _session.Response.StatusCode;\r
 181                     return (!(_session.Request.Method == "HEAD" ||\r
 182                               code.StartsWith("1") || code == "204" || code == "304"));\r
 183                 }\r
 184             }\r
 185 \r
 186             private void SendResponse()\r
 187             {\r
 188                 _clientStream.WriteLines(_session.Response.StatusLine + _session.Response.ModifiedHeaders)\r
 189                     .Write(_session.Response.Body);\r
 190             }\r
 191 \r
 192             private void HandleConnect()\r
 193             {\r
 194                 var host = "";\r
 195                 var port = 443;\r
 196                 if (!ParseAuthority(_session.Request.PathAndQuery, ref host, ref port))\r
 197                     return;\r
 198                 _server = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);\r
 199                 _server.Connect(host, port);\r
 200                 _clientStream.WriteLines("HTTP/1.0 200 Connection established\r\n\r\n");\r
 201                 Task[] tasks =\r
 202                 {\r
 203                     Task.Run(() => { TunnnelSockets(_client, _server); }),\r
 204                     Task.Run(() => { TunnnelSockets(_server, _client); })\r
 205                 };\r
 206                 Task.WaitAll(tasks);\r
 207             }\r
 208 \r
 209             private void TunnnelSockets(Socket from, Socket to)\r
 210             {\r
 211                 try\r
 212                 {\r
 213                     var buf = new byte[8192];\r
 214                     while (true)\r
 215                     {\r
 216                         var n = from.Receive(buf);\r
 217                         if (n == 0)\r
 218                             break;\r
 219                         var sent = to.Send(buf, n, SocketFlags.None);\r
 220                         if (sent < n)\r
 221                             break;\r
 222                     }\r
 223                     to.Shutdown(SocketShutdown.Send);\r
 224                 }\r
 225                 catch (SocketException)\r
 226                 {\r
 227                 }\r
 228             }\r
 229 \r
 230             private static readonly Regex HostAndPortRegex =\r
 231                 new Regex("http://([^:/]+)(?::(\\d+))?/", RegexOptions.Compiled);\r
 232 \r
 233             private Socket ConnectServer()\r
 234             {\r
 235                 string host = null;\r
 236                 var port = 80;\r
 237                 if (IsEnableUpstreamProxy)\r
 238                 {\r
 239                     host = UpstreamProxyHost;\r
 240                     port = UpstreamProxyPort;\r
 241                     goto connect;\r
 242                 }\r
 243                 var m = HostAndPortRegex.Match(_session.Request.RequestLine);\r
 244                 if (m.Success)\r
 245                 {\r
 246                     host = m.Groups[1].Value;\r
 247                     if (m.Groups[2].Success)\r
 248                         port = int.Parse(m.Groups[2].Value);\r
 249                     _session.Request.RequestLine = _session.Request.RequestLine.Remove(m.Index, m.Length - 1);\r
 250                 }\r
 251                 if (host == null && !ParseAuthority(_session.Request.Host, ref host, ref port))\r
 252                     throw new HttpProxyAbort("Can't find destination host");\r
 253                 connect:\r
 254                 var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);\r
 255                 socket.Connect(host, port);\r
 256                 return socket;\r
 257             }\r
 258 \r
 259             private static readonly Regex AuthorityRegex = new Regex("([^:]+)(?::(\\d+))?");\r
 260 \r
 261             private bool ParseAuthority(string authority, ref string host, ref int port)\r
 262             {\r
 263                 if (string.IsNullOrEmpty(authority))\r
 264                     return false;\r
 265                 var m = AuthorityRegex.Match(authority);\r
 266                 if (!m.Success)\r
 267                     return false;\r
 268                 host = m.Groups[1].Value;\r
 269                 if (m.Groups[2].Success)\r
 270                     port = int.Parse(m.Groups[2].Value);\r
 271                 return true;\r
 272             }\r
 273 \r
 274             private void Close()\r
 275             {\r
 276                 _serverStream?.Close();\r
 277                 _clientStream?.Close();\r
 278                 _server?.Close();\r
 279                 _client.Close();\r
 280             }\r
 281         }\r
 282 \r
 283         public class Session\r
 284         {\r
 285             public Request Request { get; set; } = new Request();\r
 286             public Response Response { get; set; } = new Response();\r
 287         }\r
 288 \r
 289         public class Message\r
 290         {\r
 291             private string _headers;\r
 292             public byte[] Body { get; set; }\r
 293 \r
 294             private static readonly Regex CharsetRegx = new Regex("charset=([\\w-]+)",\r
 295                 RegexOptions.Compiled | RegexOptions.IgnoreCase | RegexOptions.CultureInvariant);\r
 296 \r
 297             public int ContentLength { get; set; } = -1;\r
 298             public string TransferEncoding { get; set; }\r
 299             public string ContentType { get; set; }\r
 300             public string ContentEncoding { get; set; }\r
 301             public string Host { get; set; }\r
 302 \r
 303             public string Headers\r
 304             {\r
 305                 get => _headers;\r
 306                 set\r
 307                 {\r
 308                     _headers = value;\r
 309                     SetHeaders(_headers);\r
 310                 }\r
 311             }\r
 312 \r
 313             public virtual string ModifiedHeaders => SetConnectionClose(Headers);\r
 314 \r
 315             private string SetConnectionClose(string headers)\r
 316             {\r
 317                 return InsertHeader(RemoveHeaders(headers,\r
 318                     new[] {"connection", "keep-alive", "proxy-connection"}), "Connection: close\r\n");\r
 319             }\r
 320 \r
 321             protected string RemoveHeaders(string headers, string[] fields)\r
 322             {\r
 323                 foreach (var f in fields)\r
 324                 {\r
 325                     var m = MatchField(f, headers);\r
 326                     if (!m.Success)\r
 327                         continue;\r
 328                     headers = headers.Remove(m.Index, m.Length);\r
 329                 }\r
 330                 return headers;\r
 331             }\r
 332 \r
 333             protected string InsertHeader(string headers, string header)\r
 334             {\r
 335                 return headers.Insert(headers.Length - 2, header);\r
 336             }\r
 337 \r
 338             protected virtual void SetHeaders(string headers)\r
 339             {\r
 340                 var s = GetField("content-length");\r
 341                 if (s != null)\r
 342                 {\r
 343                     ContentLength = int.TryParse(s, out var len) ? len : -1;\r
 344                 }\r
 345                 TransferEncoding = GetField("transfer-encoding")?.ToLower(CultureInfo.InvariantCulture);\r
 346                 ContentType = GetField("content-type");\r
 347                 ContentEncoding = GetField("content-encoding");\r
 348                 Host = GetField("host");\r
 349             }\r
 350 \r
 351             protected Match MatchField(string name, string headers)\r
 352             {\r
 353                 var regex = new Regex("^" + name + ":\\s*([^\r]+)\r\n",\r
 354                     RegexOptions.CultureInvariant | RegexOptions.IgnoreCase | RegexOptions.Multiline);\r
 355                 return regex.Match(headers);\r
 356             }\r
 357 \r
 358             protected string GetField(string name)\r
 359             {\r
 360                 var m = MatchField(name, Headers);\r
 361                 return m.Success ? m.Groups[1].Value : null;\r
 362             }\r
 363 \r
 364             public string BodyAsString\r
 365             {\r
 366                 get\r
 367                 {\r
 368                     if (Body == null)\r
 369                         return "";\r
 370                     var m = CharsetRegx.Match(ContentType ?? "");\r
 371                     var encoding = Encoding.ASCII;\r
 372                     if (m.Success)\r
 373                     {\r
 374                         var name = m.Groups[1].Value;\r
 375                         if (name == "utf8")\r
 376                             name = "UTF-8";\r
 377                         encoding = Encoding.GetEncoding(name);\r
 378                     }\r
 379                     return encoding.GetString(Body);\r
 380                 }\r
 381             }\r
 382 \r
 383             public void ReadBody(HttpStream stream)\r
 384             {\r
 385                 if (TransferEncoding != null && TransferEncoding.Contains("chunked"))\r
 386                 {\r
 387                     Body = stream.ReadChunked();\r
 388                 }\r
 389                 else if (ContentLength == 0)\r
 390                 {\r
 391                 }\r
 392                 else if (ContentLength > 0)\r
 393                 {\r
 394                     var buf = new byte[ContentLength];\r
 395                     stream.Read(buf, 0, ContentLength);\r
 396                     Body = buf;\r
 397                 }\r
 398                 else\r
 399                 {\r
 400                     Body = stream.ReadToEnd();\r
 401                 }\r
 402                 if (ContentEncoding == null)\r
 403                     return;\r
 404                 var dc = new MemoryStream();\r
 405                 try\r
 406                 {\r
 407                     if (ContentEncoding == "gzip")\r
 408                         new GZipStream(new MemoryStream(Body), CompressionMode.Decompress).CopyTo(dc);\r
 409                     else if (ContentEncoding == "deflate")\r
 410                         new DeflateStream(new MemoryStream(Body), CompressionMode.Decompress).CopyTo(dc);\r
 411                 }\r
 412                 catch (Exception ex)\r
 413                 {\r
 414                     throw new HttpProxyAbort($"Fail to decode {ContentEncoding}: " + ex.Message);\r
 415                 }\r
 416                 Body = dc.ToArray();\r
 417             }\r
 418         }\r
 419 \r
 420         public class Request : Message\r
 421         {\r
 422             private string _requestLine;\r
 423 \r
 424             public string RequestLine\r
 425             {\r
 426                 get => _requestLine;\r
 427                 set\r
 428                 {\r
 429                     _requestLine = value;\r
 430                     var f = _requestLine.Split(' ');\r
 431                     if (f.Length < 3)\r
 432                         throw new HttpProxyAbort("Invalid request line");\r
 433                     Method = f[0];\r
 434                     PathAndQuery = f.Length < 2 ? "" : f[1];\r
 435                 }\r
 436             }\r
 437 \r
 438             public string Method { get; private set; }\r
 439             public string PathAndQuery { get; private set; }\r
 440         }\r
 441 \r
 442         public class Response : Message\r
 443         {\r
 444             private string _statusLine;\r
 445 \r
 446             public override string ModifiedHeaders =>\r
 447                 InsertContentLength(RemoveHeaders(base.ModifiedHeaders,\r
 448                     new[] {"transfer-encoding", "content-encoding", "content-length"}));\r
 449 \r
 450             private string InsertContentLength(string headers)\r
 451             {\r
 452                 return Body == null ? headers : InsertHeader(headers, $"Content-Length: {Body.Length}\r\n");\r
 453             }\r
 454 \r
 455             public string StatusLine\r
 456             {\r
 457                 get => _statusLine;\r
 458                 set\r
 459                 {\r
 460                     _statusLine = value;\r
 461                     var f = _statusLine.Split(' ');\r
 462                     if (f.Length < 3)\r
 463                         throw new HttpProxyAbort("Invalid status line");\r
 464                     StatusCode = _statusLine.Split(' ')[1];\r
 465                 }\r
 466             }\r
 467 \r
 468             public string StatusCode { get; private set; }\r
 469         }\r
 470 \r
 471         private class HttpProxyAbort : Exception\r
 472         {\r
 473             public HttpProxyAbort(string message) : base(message)\r
 474             {\r
 475             }\r
 476         }\r
 477 \r
 478         public class HttpStream\r
 479         {\r
 480             private readonly Socket _socket;\r
 481             private readonly byte[] _buffer = new byte[4096];\r
 482             private int _available;\r
 483             private int _position;\r
 484 \r
 485             public HttpStream(Socket socket)\r
 486             {\r
 487                 _socket = socket;\r
 488                 socket.NoDelay = true;\r
 489             }\r
 490 \r
 491             public string ReadLine()\r
 492             {\r
 493                 var sb = new StringBuilder();\r
 494                 int ch;\r
 495                 while ((ch = ReadByte()) != -1)\r
 496                 {\r
 497                     sb.Append((char)ch);\r
 498                     if (ch == '\n')\r
 499                         break;\r
 500                 }\r
 501                 return sb.ToString();\r
 502             }\r
 503 \r
 504             private int ReadByte()\r
 505             {\r
 506                 if (_position < _available)\r
 507                     return _buffer[_position++];\r
 508                 _available = _socket.Receive(_buffer, 0, _buffer.Length, SocketFlags.None);\r
 509                 _position = 0;\r
 510                 return _available == 0 ? -1 : _buffer[_position++];\r
 511             }\r
 512 \r
 513             public HttpStream WriteLines(string s)\r
 514             {\r
 515                 var buf = Encoding.ASCII.GetBytes(s);\r
 516                 Write(buf, 0, buf.Length);\r
 517                 return this;\r
 518             }\r
 519 \r
 520             public string ReadHeaders()\r
 521             {\r
 522                 var sb = new StringBuilder();\r
 523                 string line;\r
 524                 do\r
 525                 {\r
 526                     line = ReadLine();\r
 527                     sb.Append(line);\r
 528                 } while (line != "\r\n");\r
 529                 return sb.ToString();\r
 530             }\r
 531 \r
 532             public byte[] ReadChunked()\r
 533             {\r
 534                 var buf = new MemoryStream();\r
 535                 while (true)\r
 536                 {\r
 537                     var size = ReadLine();\r
 538                     if (size.Length < 3)\r
 539                         break;\r
 540                     var ext = size.IndexOf(';');\r
 541                     size = ext == -1 ? size.Substring(0, size.Length - 2) : size.Substring(0, ext);\r
 542                     if (!int.TryParse(size, NumberStyles.HexNumber, CultureInfo.InvariantCulture, out var val))\r
 543                         throw new HttpProxyAbort("Can't parse chunk size: " + size);\r
 544                     if (val == 0)\r
 545                         break;\r
 546                     var chunk = new byte[val];\r
 547                     Read(chunk, 0, chunk.Length);\r
 548                     buf.Write(chunk, 0, chunk.Length);\r
 549                     ReadLine();\r
 550                 }\r
 551                 string line;\r
 552                 do\r
 553                 {\r
 554                     line = ReadLine();\r
 555                 } while (line != "" && line != "\r\n");\r
 556                 return buf.ToArray();\r
 557             }\r
 558 \r
 559             public byte[] ReadToEnd()\r
 560             {\r
 561                 var result = new MemoryStream();\r
 562                 var buf = new byte[4096];\r
 563                 int len;\r
 564                 while ((len = Read(buf, 0, buf.Length)) > 0)\r
 565                     result.Write(buf, 0, len);\r
 566                 return result.ToArray();\r
 567             }\r
 568 \r
 569             public HttpStream Write(byte[] body)\r
 570             {\r
 571                 if (body != null)\r
 572                     Write(body, 0, body.Length);\r
 573                 return this;\r
 574             }\r
 575 \r
 576             public int Read(byte[] buf, int offset, int count)\r
 577             {\r
 578                 var total = 0;\r
 579                 do\r
 580                 {\r
 581                     int n;\r
 582                     if (_position < _available)\r
 583                     {\r
 584                         n = Math.Min(count, _available - _position);\r
 585                         Buffer.BlockCopy(_buffer, _position, buf, 0, n);\r
 586                         _position += n;\r
 587                     }\r
 588                     else\r
 589                     {\r
 590                         n = _socket.Receive(buf, offset, count, SocketFlags.None);\r
 591                         if (n == 0)\r
 592                             return total == 0 ? n : total;\r
 593                     }\r
 594                     count -= n;\r
 595                     offset += n;\r
 596                     total += n;\r
 597                 } while (count > 0);\r
 598                 return total;\r
 599             }\r
 600 \r
 601             public void Write(byte[] buf, int offset, int count)\r
 602             {\r
 603                 do\r
 604                 {\r
 605                     var n = _socket.Send(buf, offset, count, SocketFlags.None);\r
 606                     if (n == 0)\r
 607                         return;\r
 608                     count -= n;\r
 609                     offset += n;\r
 610                 } while (count > 0);\r
 611             }\r
 612 \r
 613             public HttpStream Close()\r
 614             {\r
 615                 _socket.Close();\r
 616                 return this;\r
 617             }\r
 618         }\r
 619     }\r
 620 }