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   1 /**
   2  * Copyright (c) 2010-2023 Contributors to the openHAB project
   3  *
   4  * See the NOTICE file(s) distributed with this work for additional
   5  * information.
   6  *
   7  * This program and the accompanying materials are made available under the
   8  * terms of the Eclipse Public License 2.0 which is available at
   9  * http://www.eclipse.org/legal/epl-2.0
  10  *
  11  * SPDX-License-Identifier: EPL-2.0
  12  */
  13 package org.openhab.binding.digitalstrom.internal.lib.serverconnection.impl;
  14
  15 import java.io.ByteArrayInputStream;
  16 import java.io.File;
  17 import java.io.FileInputStream;
  18 import java.io.FileNotFoundException;
  19 import java.io.FileWriter;
  20 import java.io.IOException;
  21 import java.io.InputStream;
  22 import java.net.HttpURLConnection;
  23 import java.net.MalformedURLException;
  24 import java.net.SocketTimeoutException;
  25 import java.net.URL;
  26 import java.nio.charset.StandardCharsets;
  27 import java.security.KeyManagementException;
  28 import java.security.NoSuchAlgorithmException;
  29 import java.security.SecureRandom;
  30 import java.security.Security;
  31 import java.security.cert.CertificateEncodingException;
  32 import java.security.cert.CertificateException;
  33 import java.security.cert.CertificateFactory;
  34 import java.security.cert.X509Certificate;
  35 import java.util.Base64;
  36
  37 import javax.net.ssl.HostnameVerifier;
  38 import javax.net.ssl.HttpsURLConnection;
  39 import javax.net.ssl.SSLContext;
  40 import javax.net.ssl.SSLHandshakeException;
  41 import javax.net.ssl.SSLSession;
  42 import javax.net.ssl.SSLSocketFactory;
  43 import javax.net.ssl.TrustManager;
  44 import javax.net.ssl.X509TrustManager;
  45
  46 import org.openhab.binding.digitalstrom.internal.lib.config.Config;
  47 import org.openhab.binding.digitalstrom.internal.lib.manager.ConnectionManager;
  48 import org.openhab.binding.digitalstrom.internal.lib.serverconnection.HttpTransport;
  49 import org.openhab.binding.digitalstrom.internal.lib.serverconnection.simpledsrequestbuilder.constants.ParameterKeys;
  50 import org.slf4j.Logger;
  51 import org.slf4j.LoggerFactory;
  52
  53 /**
  54  * The {@link HttpTransportImpl} executes a request to the digitalSTROM-Server.
  55  * <p>
  56  * If a {@link Config} is given at the constructor. It sets the SSL-Certificate what is set in
  57  * {@link Config#getCert()}. If there is no SSL-Certificate, but a path to an external SSL-Certificate file what is set
  58  * in {@link Config#getTrustCertPath()} this will be set. If no SSL-Certificate is set in the {@link Config} it will be
  59  * red out from the server and set in {@link Config#setCert(String)}.
  60  *
  61  * <p>
  62  * If no {@link Config} is given the SSL-Certificate will be stored locally.
  63  *
  64  * <p>
  65  * The method {@link #writePEMCertFile(String)} saves the SSL-Certificate in a file at the given path. If all
  66  * SSL-Certificates shout be ignored the flag <i>exeptAllCerts</i> have to be true at the constructor
  67  * </p>
  68  * <p>
  69  * If a {@link ConnectionManager} is given at the constructor, the session-token is not needed by requests and the
  70  * {@link org.openhab.binding.digitalstrom.internal.lib.listener.ConnectionListener}, which is registered at the
  71  * {@link ConnectionManager}, will be automatically informed about
  72  * connection state changes through the {@link #execute(String, int, int)} method.
  73  * </p>
  74  *
  75  * @author Michael Ochel - Initial contribution
  76  * @author Matthias Siegele - Initial contribution
  77  */
  78 public class HttpTransportImpl implements HttpTransport {
  79
  80     private static final String LINE_SEPERATOR = System.getProperty("line.separator");
  81     private static final String BEGIN_CERT = "-----BEGIN CERTIFICATE-----" + LINE_SEPERATOR;
  82     private static final String END_CERT = LINE_SEPERATOR + "-----END CERTIFICATE-----" + LINE_SEPERATOR;
  83
  84     private final Logger logger = LoggerFactory.getLogger(HttpTransportImpl.class);
  85     private static final short MAY_A_NEW_SESSION_TOKEN_IS_NEEDED = 1;
  86
  87     private String uri;
  88
  89     private int connectTimeout;
  90     private int readTimeout;
  91
  92     private Config config;
  93
  94     private ConnectionManager connectionManager;
  95
  96     private String cert;
  97     private SSLSocketFactory sslSocketFactory;
  98     private final HostnameVerifier hostnameVerifier = new HostnameVerifier() {
  99
 100         @Override
 101         public boolean verify(String arg0, SSLSession arg1) {
 102             return arg0.equals(arg1.getPeerHost()) || arg0.contains("dss.local.");
 103         }
 104     };
 105
 106     /**
 107      * Creates a new {@link HttpTransportImpl} with registration of the given {@link ConnectionManager} and set ignore
 108      * all SSL-Certificates. The {@link Config} will be automatically added from the configurations of the given
 109      * {@link ConnectionManager}.
 110      *
 111      * @param connectionManager to check connection, can be null
 112      * @param exeptAllCerts (true = all will ignore)
 113      */
 114     public HttpTransportImpl(ConnectionManager connectionManager, boolean exeptAllCerts) {
 115         this.connectionManager = connectionManager;
 116         this.config = connectionManager.getConfig();
 117         init(config.getHost(), config.getConnectionTimeout(), config.getReadTimeout(), exeptAllCerts);
 118     }
 119
 120     /**
 121      * Creates a new {@link HttpTransportImpl} with configurations of the given {@link Config} and set ignore all
 122      * SSL-Certificates.
 123      *
 124      * @param config to get configurations, must not be null
 125      * @param exeptAllCerts (true = all will ignore)
 126      */
 127     public HttpTransportImpl(Config config, boolean exeptAllCerts) {
 128         this.config = config;
 129         init(config.getHost(), config.getConnectionTimeout(), config.getReadTimeout(), exeptAllCerts);
 130     }
 131
 132     /**
 133      * Creates a new {@link HttpTransportImpl} with configurations of the given {@link Config}.
 134      *
 135      * @param config to get configurations, must not be null
 136      */
 137     public HttpTransportImpl(Config config) {
 138         this.config = config;
 139         init(config.getHost(), config.getConnectionTimeout(), config.getReadTimeout(), false);
 140     }
 141
 142     /**
 143      * Creates a new {@link HttpTransportImpl}.
 144      *
 145      * @param uri of the server, must not be null
 146      */
 147     public HttpTransportImpl(String uri) {
 148         init(uri, Config.DEFAULT_CONNECTION_TIMEOUT, Config.DEFAULT_READ_TIMEOUT, false);
 149     }
 150
 151     /**
 152      * Creates a new {@link HttpTransportImpl} and set ignore all SSL-Certificates.
 153      *
 154      * @param uri of the server, must not be null
 155      * @param exeptAllCerts (true = all will ignore)
 156      */
 157     public HttpTransportImpl(String uri, boolean exeptAllCerts) {
 158         init(uri, Config.DEFAULT_CONNECTION_TIMEOUT, Config.DEFAULT_READ_TIMEOUT, exeptAllCerts);
 159     }
 160
 161     /**
 162      * Creates a new {@link HttpTransportImpl}.
 163      *
 164      * @param uri of the server, must not be null
 165      * @param connectTimeout to set
 166      * @param readTimeout to set
 167      */
 168     public HttpTransportImpl(String uri, int connectTimeout, int readTimeout) {
 169         init(uri, connectTimeout, readTimeout, false);
 170     }
 171
 172     /**
 173      * Creates a new {@link HttpTransportImpl} and set ignore all SSL-Certificates..
 174      *
 175      * @param uri of the server, must not be null
 176      * @param connectTimeout to set
 177      * @param readTimeout to set
 178      * @param exeptAllCerts (true = all will ignore)
 179      */
 180     public HttpTransportImpl(String uri, int connectTimeout, int readTimeout, boolean exeptAllCerts) {
 181         init(uri, connectTimeout, readTimeout, exeptAllCerts);
 182     }
 183
 184     private void init(String uri, int connectTimeout, int readTimeout, boolean exeptAllCerts) {
 185         logger.debug("init HttpTransportImpl");
 186         this.uri = fixURI(uri);
 187         this.connectTimeout = connectTimeout;
 188         this.readTimeout = readTimeout;
 189         // Check SSL Certificate
 190         if (exeptAllCerts) {
 191             sslSocketFactory = generateSSLContextWhichAcceptAllSSLCertificats();
 192         } else {
 193             if (config != null) {
 194                 cert = config.getCert();
 195                 logger.debug("generate SSLcontext from config cert");
 196                 if (cert != null && !cert.isBlank()) {
 197                     sslSocketFactory = generateSSLContextFromPEMCertString(cert);
 198                 } else {
 199                     String trustCertPath = config.getTrustCertPath();
 200                     if (trustCertPath != null && !trustCertPath.isBlank()) {
 201                         logger.debug("generate SSLcontext from config cert path");
 202                         cert = readPEMCertificateStringFromFile(trustCertPath);
 203                         if (cert != null && !cert.isBlank()) {
 204                             sslSocketFactory = generateSSLContextFromPEMCertString(cert);
 205                         }
 206                     } else {
 207                         logger.debug("generate SSLcontext from server");
 208                         cert = getPEMCertificateFromServer(this.uri);
 209                         sslSocketFactory = generateSSLContextFromPEMCertString(cert);
 210                         if (sslSocketFactory != null) {
 211                             config.setCert(cert);
 212                         }
 213                     }
 214                 }
 215             } else {
 216                 logger.debug("generate SSLcontext from server");
 217                 cert = getPEMCertificateFromServer(this.uri);
 218                 sslSocketFactory = generateSSLContextFromPEMCertString(cert);
 219             }
 220         }
 221     }
 222
 223     private String fixURI(String uri) {
 224         String fixedURI = uri;
 225         if (!fixedURI.startsWith("https://")) {
 226             fixedURI = "https://" + fixedURI;
 227         }
 228         if (fixedURI.split(":").length != 3) {
 229             fixedURI = fixedURI + ":8080";
 230         }
 231         return fixedURI;
 232     }
 233
 234     private String fixRequest(String request) {
 235         return request.replace(" ", "");
 236     }
 237
 238     @Override
 239     public String execute(String request) {
 240         return execute(request, this.connectTimeout, this.readTimeout);
 241     }
 242
 243     private short loginCounter = 0;
 244
 245     @Override
 246     public String execute(String request, int connectTimeout, int readTimeout) {
 247         // NOTE: We will only show exceptions in the debug level, because they will be handled in the checkConnection()
 248         // method and this changes the bridge state. If a command was send it fails than and a sensorJob will be
 249         // execute the next time, by TimeOutExceptions. By other exceptions the checkConnection() method handles it in
 250         // max 1 second.
 251         String response = null;
 252         HttpsURLConnection connection = null;
 253         try {
 254             String correctedRequest = checkSessionToken(request);
 255             connection = getConnection(correctedRequest, connectTimeout, readTimeout);
 256             if (connection != null) {
 257                 connection.connect();
 258                 final int responseCode = connection.getResponseCode();
 259                 if (responseCode != HttpURLConnection.HTTP_FORBIDDEN) {
 260                     if (responseCode == HttpURLConnection.HTTP_INTERNAL_ERROR) {
 261                         response = new String(connection.getErrorStream().readAllBytes(), StandardCharsets.UTF_8);
 262                     } else {
 263                         response = new String(connection.getInputStream().readAllBytes(), StandardCharsets.UTF_8);
 264                     }
 265                     if (response != null) {
 266                         if (!response.contains("Authentication failed")) {
 267                             if (loginCounter > 0) {
 268                                 connectionManager.checkConnection(responseCode);
 269                             }
 270                             loginCounter = 0;
 271                         } else {
 272                             connectionManager.checkConnection(ConnectionManager.AUTHENTIFICATION_PROBLEM);
 273                             loginCounter++;
 274                         }
 275                     }
 276
 277                 }
 278                 connection.disconnect();
 279                 if (response == null && connectionManager != null
 280                         && loginCounter <= MAY_A_NEW_SESSION_TOKEN_IS_NEEDED) {
 281                     if (responseCode == HttpURLConnection.HTTP_FORBIDDEN) {
 282                         execute(addSessionToken(correctedRequest, connectionManager.getNewSessionToken()),
 283                                 connectTimeout, readTimeout);
 284                         loginCounter++;
 285                     } else {
 286                         connectionManager.checkConnection(responseCode);
 287                         loginCounter++;
 288                         return null;
 289                     }
 290                 }
 291                 return response;
 292             }
 293         } catch (SocketTimeoutException e) {
 294             informConnectionManager(ConnectionManager.SOCKET_TIMEOUT_EXCEPTION);
 295         } catch (java.net.ConnectException e) {
 296             informConnectionManager(ConnectionManager.CONNECTION_EXCEPTION);
 297         } catch (MalformedURLException e) {
 298             informConnectionManager(ConnectionManager.MALFORMED_URL_EXCEPTION);
 299         } catch (java.net.UnknownHostException e) {
 300             informConnectionManager(ConnectionManager.UNKNOWN_HOST_EXCEPTION);
 301         } catch (SSLHandshakeException e) {
 302             informConnectionManager(ConnectionManager.SSL_HANDSHAKE_EXCEPTION);
 303         } catch (IOException e) {
 304             logger.error("An IOException occurred: ", e);
 305             informConnectionManager(ConnectionManager.GENERAL_EXCEPTION);
 306         } finally {
 307             if (connection != null) {
 308                 connection.disconnect();
 309             }
 310         }
 311         return null;
 312     }
 313
 314     private boolean informConnectionManager(int code) {
 315         if (connectionManager != null && loginCounter < MAY_A_NEW_SESSION_TOKEN_IS_NEEDED) {
 316             connectionManager.checkConnection(code);
 317             return true;
 318         }
 319         return false;
 320     }
 321
 322     private String checkSessionToken(String request) {
 323         if (checkNeededSessionToken(request)) {
 324             if (connectionManager != null) {
 325                 String sessionToken = connectionManager.getSessionToken();
 326                 if (sessionToken == null) {
 327                     return addSessionToken(request, connectionManager.getNewSessionToken());
 328                 }
 329                 return addSessionToken(request, sessionToken);
 330             }
 331         }
 332         return request;
 333     }
 334
 335     private boolean checkNeededSessionToken(String request) {
 336         String requestFirstPart = request;
 337         int indexOfSeparator = request.indexOf("?");
 338         if (indexOfSeparator >= 0) {
 339             requestFirstPart = request.substring(0, request.indexOf("?"));
 340         }
 341         String functionName = requestFirstPart.substring(requestFirstPart.lastIndexOf("/") + 1);
 342         return !DsAPIImpl.METHODS_MUST_NOT_BE_LOGGED_IN.contains(functionName);
 343     }
 344
 345     private String addSessionToken(String request, String sessionToken) {
 346         String correctedRequest = request;
 347         if (!correctedRequest.contains(ParameterKeys.TOKEN)) {
 348             if (correctedRequest.contains("?")) {
 349                 correctedRequest = correctedRequest + "&" + ParameterKeys.TOKEN + "=" + sessionToken;
 350             } else {
 351                 correctedRequest = correctedRequest + "?" + ParameterKeys.TOKEN + "=" + sessionToken;
 352             }
 353         } else {
 354             String strippedRequest = correctedRequest
 355                     .substring(correctedRequest.indexOf(ParameterKeys.TOKEN + "=") + ParameterKeys.TOKEN.length() + 1);
 356             int indexOfSeparator = strippedRequest.indexOf("&");
 357             if (indexOfSeparator >= 0) {
 358                 strippedRequest = strippedRequest.substring(0, indexOfSeparator);
 359             }
 360             correctedRequest = correctedRequest.replaceFirst(strippedRequest, sessionToken);
 361         }
 362         return correctedRequest;
 363     }
 364
 365     private HttpsURLConnection getConnection(String request, int connectTimeout, int readTimeout) throws IOException {
 366         String correctedRequest = request;
 367         if (correctedRequest != null && !correctedRequest.isBlank()) {
 368             correctedRequest = fixRequest(correctedRequest);
 369             URL url = new URL(this.uri + correctedRequest);
 370             HttpsURLConnection connection = (HttpsURLConnection) url.openConnection();
 371             if (connection != null) {
 372                 connection.setConnectTimeout(connectTimeout);
 373                 connection.setReadTimeout(readTimeout);
 374                 if (sslSocketFactory != null) {
 375                     connection.setSSLSocketFactory(sslSocketFactory);
 376                 }
 377                 if (hostnameVerifier != null) {
 378                     connection.setHostnameVerifier(hostnameVerifier);
 379                 }
 380             }
 381             return connection;
 382         }
 383         return null;
 384     }
 385
 386     @Override
 387     public int checkConnection(String testRequest) {
 388         try {
 389             HttpsURLConnection connection = getConnection(testRequest, connectTimeout, readTimeout);
 390             if (connection != null) {
 391                 connection.connect();
 392                 if (connection.getResponseCode() == HttpURLConnection.HTTP_OK) {
 393                     if (new String(connection.getInputStream().readAllBytes(), StandardCharsets.UTF_8)
 394                             .contains("Authentication failed")) {
 395                         return ConnectionManager.AUTHENTIFICATION_PROBLEM;
 396                     }
 397                 }
 398                 connection.disconnect();
 399                 return connection.getResponseCode();
 400             } else {
 401                 return ConnectionManager.GENERAL_EXCEPTION;
 402             }
 403         } catch (SocketTimeoutException e) {
 404             return ConnectionManager.SOCKET_TIMEOUT_EXCEPTION;
 405         } catch (java.net.ConnectException e) {
 406             return ConnectionManager.CONNECTION_EXCEPTION;
 407         } catch (MalformedURLException e) {
 408             return ConnectionManager.MALFORMED_URL_EXCEPTION;
 409         } catch (java.net.UnknownHostException e) {
 410             return ConnectionManager.UNKNOWN_HOST_EXCEPTION;
 411         } catch (IOException e) {
 412             return ConnectionManager.GENERAL_EXCEPTION;
 413         }
 414     }
 415
 416     @Override
 417     public int getSensordataConnectionTimeout() {
 418         return config != null ? config.getSensordataConnectionTimeout() : Config.DEFAULT_SENSORDATA_CONNECTION_TIMEOUT;
 419     }
 420
 421     @Override
 422     public int getSensordataReadTimeout() {
 423         return config != null ? config.getSensordataReadTimeout() : Config.DEFAULT_SENSORDATA_READ_TIMEOUT;
 424     }
 425
 426     private String readPEMCertificateStringFromFile(String path) {
 427         if (path == null || path.isBlank()) {
 428             logger.error("Path is empty.");
 429         } else {
 430             File dssCert = new File(path);
 431             if (dssCert.exists()) {
 432                 if (path.endsWith(".crt")) {
 433                     try (InputStream certInputStream = new FileInputStream(dssCert)) {
 434                         String cert = new String(certInputStream.readAllBytes(), StandardCharsets.UTF_8);
 435                         if (cert.startsWith(BEGIN_CERT)) {
 436                             return cert;
 437                         } else {
 438                             logger.error("File is not a PEM certificate file. PEM-Certificates starts with: {}",
 439                                     BEGIN_CERT);
 440                         }
 441                     } catch (FileNotFoundException e) {
 442                         logger.error("Can't find a certificate file at the path: {}\nPlease check the path!", path);
 443                     } catch (IOException e) {
 444                         logger.error("An IOException occurred: ", e);
 445                     }
 446                 } else {
 447                     logger.error("File is not a certificate (.crt) file.");
 448                 }
 449             } else {
 450                 logger.error("File not found");
 451             }
 452         }
 453         return null;
 454     }
 455
 456     @Override
 457     public String writePEMCertFile(String path) {
 458         String correctedPath = path == null ? "" : path.trim();
 459         File certFilePath;
 460         if (!correctedPath.isBlank()) {
 461             certFilePath = new File(correctedPath);
 462             boolean pathExists = certFilePath.exists();
 463             if (!pathExists) {
 464                 pathExists = certFilePath.mkdirs();
 465             }
 466             if (pathExists && !correctedPath.endsWith("/")) {
 467                 correctedPath = correctedPath + "/";
 468             }
 469         }
 470         InputStream certInputStream = new ByteArrayInputStream(cert.getBytes(StandardCharsets.UTF_8));
 471         X509Certificate trustedCert;
 472         try {
 473             trustedCert = (X509Certificate) CertificateFactory.getInstance("X.509")
 474                     .generateCertificate(certInputStream);
 475
 476             certFilePath = new File(
 477                     correctedPath + trustedCert.getSubjectDN().getName().split(",")[0].substring(2) + ".crt");
 478             if (!certFilePath.exists()) {
 479                 certFilePath.createNewFile();
 480                 FileWriter writer = new FileWriter(certFilePath, true);
 481                 writer.write(cert);
 482                 writer.flush();
 483                 writer.close();
 484                 return certFilePath.getAbsolutePath();
 485             } else {
 486                 logger.error("File allready exists!");
 487             }
 488         } catch (IOException e) {
 489             logger.error("An IOException occurred: ", e);
 490         } catch (CertificateException e1) {
 491             logger.error("A CertificateException occurred: ", e1);
 492         }
 493         return null;
 494     }
 495
 496     private SSLSocketFactory generateSSLContextFromPEMCertString(String pemCert) {
 497         if (pemCert != null && !pemCert.isBlank() && pemCert.startsWith(BEGIN_CERT)) {
 498             try {
 499                 InputStream certInputStream = new ByteArrayInputStream(pemCert.getBytes(StandardCharsets.UTF_8));
 500                 final X509Certificate trustedCert = (X509Certificate) CertificateFactory.getInstance("X.509")
 501                         .generateCertificate(certInputStream);
 502
 503                 final TrustManager[] trustManager = new TrustManager[] { new X509TrustManager() {
 504
 505                     @Override
 506                     public java.security.cert.X509Certificate[] getAcceptedIssuers() {
 507                         return null;
 508                     }
 509
 510                     @Override
 511                     public void checkClientTrusted(java.security.cert.X509Certificate[] certs, String authType)
 512                             throws CertificateException {
 513                         if (!certs[0].equals(trustedCert)) {
 514                             throw new CertificateException();
 515                         }
 516                     }
 517
 518                     @Override
 519                     public void checkServerTrusted(java.security.cert.X509Certificate[] certs, String authType)
 520                             throws CertificateException {
 521                         if (!certs[0].equals(trustedCert)) {
 522                             throw new CertificateException();
 523                         }
 524                     }
 525                 } };
 526
 527                 SSLContext sslContext = SSLContext.getInstance("SSL");
 528                 sslContext.init(null, trustManager, new java.security.SecureRandom());
 529                 return sslContext.getSocketFactory();
 530             } catch (NoSuchAlgorithmException e) {
 531                 logger.error("A NoSuchAlgorithmException occurred: ", e);
 532             } catch (KeyManagementException e) {
 533                 logger.error("A KeyManagementException occurred: ", e);
 534             } catch (CertificateException e) {
 535                 logger.error("A CertificateException occurred: ", e);
 536             }
 537         } else {
 538             logger.error("Cert is empty");
 539         }
 540         return null;
 541     }
 542
 543     private String getPEMCertificateFromServer(String host) {
 544         HttpsURLConnection connection = null;
 545         try {
 546             URL url = new URL(host);
 547
 548             connection = (HttpsURLConnection) url.openConnection();
 549             connection.setHostnameVerifier(hostnameVerifier);
 550             connection.setSSLSocketFactory(generateSSLContextWhichAcceptAllSSLCertificats());
 551             connection.connect();
 552
 553             java.security.cert.Certificate[] cert = connection.getServerCertificates();
 554             connection.disconnect();
 555
 556             byte[] by = ((X509Certificate) cert[0]).getEncoded();
 557             if (by.length != 0) {
 558                 return BEGIN_CERT + Base64.getEncoder().encodeToString(by) + END_CERT;
 559             }
 560         } catch (MalformedURLException e) {
 561             if (!informConnectionManager(ConnectionManager.MALFORMED_URL_EXCEPTION)) {
 562                 logger.error("A MalformedURLException occurred: ", e);
 563             }
 564         } catch (IOException e) {
 565             short code = ConnectionManager.GENERAL_EXCEPTION;
 566             if (e instanceof java.net.ConnectException) {
 567                 code = ConnectionManager.CONNECTION_EXCEPTION;
 568             } else if (e instanceof java.net.UnknownHostException) {
 569                 code = ConnectionManager.UNKNOWN_HOST_EXCEPTION;
 570             }
 571             if (!informConnectionManager(code) || code == -1) {
 572                 logger.error("An IOException occurred: ", e);
 573             }
 574         } catch (CertificateEncodingException e) {
 575             logger.error("A CertificateEncodingException occurred: ", e);
 576         } finally {
 577             if (connection != null) {
 578                 connection.disconnect();
 579             }
 580         }
 581         return null;
 582     }
 583
 584     private SSLSocketFactory generateSSLContextWhichAcceptAllSSLCertificats() {
 585         Security.addProvider(Security.getProvider("SunJCE"));
 586         TrustManager[] trustAllCerts = new TrustManager[] { new X509TrustManager() {
 587
 588             @Override
 589             public java.security.cert.X509Certificate[] getAcceptedIssuers() {
 590                 return null;
 591             }
 592
 593             @Override
 594             public void checkClientTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {
 595             }
 596
 597             @Override
 598             public void checkServerTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {
 599             }
 600         } };
 601
 602         try {
 603             SSLContext sslContext = SSLContext.getInstance("SSL");
 604
 605             sslContext.init(null, trustAllCerts, new SecureRandom());
 606
 607             return sslContext.getSocketFactory();
 608         } catch (KeyManagementException e) {
 609             logger.error("A KeyManagementException occurred", e);
 610         } catch (NoSuchAlgorithmException e) {
 611             logger.error("A NoSuchAlgorithmException occurred", e);
 612         }
 613         return null;
 614     }
 615 }