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