src/com/owncloud/android/operations/DetectAuthenticationMethodOperation.java

   1 /* ownCloud Android Library is available under MIT license
   2  *   Copyright (C) 2014 ownCloud Inc.
   3  *
   4  *   Permission is hereby granted, free of charge, to any person obtaining a copy
   5  *   of this software and associated documentation files (the "Software"), to deal
   6  *   in the Software without restriction, including without limitation the rights
   7  *   to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   8  *   copies of the Software, and to permit persons to whom the Software is
   9  *   furnished to do so, subject to the following conditions:
  10  *
  11  *   The above copyright notice and this permission notice shall be included in
  12  *   all copies or substantial portions of the Software.
  13  *
  14  *   THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  15  *   EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  16  *   MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  17  *   NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  18  *   BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  19  *   ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  20  *   CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  21  *   THE SOFTWARE.
  22  *
  23  */
  24
  25 package com.owncloud.android.operations;
  26
  27 import java.util.ArrayList;
  28
  29 import com.owncloud.android.lib.common.OwnCloudClient;
  30 import com.owncloud.android.lib.common.operations.OnRemoteOperationListener;
  31 import com.owncloud.android.lib.common.operations.RemoteOperation;
  32 import com.owncloud.android.lib.common.operations.RemoteOperationResult;
  33 import com.owncloud.android.lib.common.operations.RemoteOperationResult.ResultCode;
  34 import com.owncloud.android.lib.resources.files.ExistenceCheckRemoteOperation;
  35
  36 import android.content.Context;
  37 import android.net.Uri;
  38 import android.util.Log;
  39
  40 /**
  41  * Operation to find out what authentication method requires
  42  * the server to access files.
  43  *
  44  * Basically, tries to access to the root folder without authorization
  45  * and analyzes the response.
  46  *
  47  * When successful, the instance of {@link RemoteOperationResult} passed
  48  * through {@link OnRemoteOperationListener#onRemoteOperationFinish(RemoteOperation,
  49  * RemoteOperationResult)} returns in {@link RemoteOperationResult#getData()}
  50  * a value of {@link AuthenticationMethod}.
  51  *
  52  * @author David A. Velasco
  53  */
  54 public class DetectAuthenticationMethodOperation extends RemoteOperation {
  55
  56     private static final String TAG = DetectAuthenticationMethodOperation.class.getSimpleName();
  57
  58     public enum AuthenticationMethod {
  59         UNKNOWN,
  60         NONE,
  61         BASIC_HTTP_AUTH,
  62         SAML_WEB_SSO,
  63         BEARER_TOKEN
  64     }
  65
  66     private Context mContext;
  67
  68     /**
  69      * Constructor
  70      *
  71      * @param context       Android context of the caller.
  72      */
  73     public DetectAuthenticationMethodOperation(Context context) {
  74         mContext = context;
  75     }
  76
  77
  78     /**
  79      *  Performs the operation.
  80      *
  81      *  Triggers a check of existence on the root folder of the server, granting
  82      *  that the request is not authenticated.
  83      *
  84      *  Analyzes the result of check to find out what authentication method, if
  85      *  any, is requested by the server.
  86      */
  87         @Override
  88         protected RemoteOperationResult run(OwnCloudClient client) {
  89         RemoteOperationResult result = null;
  90         AuthenticationMethod authMethod = AuthenticationMethod.UNKNOWN;
  91
  92         RemoteOperation operation = new ExistenceCheckRemoteOperation("", mContext, false);
  93         client.setBasicCredentials("", "");
  94         client.setFollowRedirects(false);
  95
  96         // try to access the root folder, following redirections but not SAML SSO redirections
  97         result = operation.execute(client);
  98         String redirectedLocation = result.getRedirectedLocation();
  99         while (redirectedLocation != null && redirectedLocation.length() > 0 && !result.isIdPRedirection()) {
 100             client.setWebdavUri(Uri.parse(result.getRedirectedLocation()));
 101             result = operation.execute(client);
 102             redirectedLocation = result.getRedirectedLocation();
 103         }
 104
 105         // analyze response
 106         if (result.getCode() == ResultCode.UNAUTHORIZED) {
 107             String authRequest = ((result.getAuthenticateHeader()).trim()).toLowerCase();
 108             if (authRequest.startsWith("basic")) {
 109                 authMethod = AuthenticationMethod.BASIC_HTTP_AUTH;
 110
 111             } else if (authRequest.startsWith("bearer")) {
 112                 authMethod = AuthenticationMethod.BEARER_TOKEN;
 113             }
 114             // else - fall back to UNKNOWN
 115
 116         } else if (result.isSuccess()) {
 117             authMethod = AuthenticationMethod.NONE;
 118
 119         } else if (result.isIdPRedirection()) {
 120             authMethod = AuthenticationMethod.SAML_WEB_SSO;
 121         }
 122         // else - fall back to UNKNOWN
 123         Log.d(TAG, "Authentication method found: " + authenticationMethodToString(authMethod));
 124
 125         ArrayList<Object> data = new ArrayList<Object>();
 126         data.add(authMethod);
 127         result.setData(data);
 128         return result;  // same result instance, so that other errors can be handled by the caller transparently
 129         }
 130
 131
 132         private String authenticationMethodToString(AuthenticationMethod value) {
 133             switch (value){
 134             case NONE:
 135                 return "NONE";
 136             case BASIC_HTTP_AUTH:
 137                 return "BASIC_HTTP_AUTH";
 138             case BEARER_TOKEN:
 139                 return "BEARER_TOKEN";
 140             case SAML_WEB_SSO:
 141                 return "SAML_WEB_SSO";
 142             default:
 143             return "UNKNOWN";
 144             }
 145     }
 146
 147 }