michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: package org.mozilla.gecko.tokenserver;
michael@0: 
michael@0: import java.io.IOException;
michael@0: import java.net.URI;
michael@0: import java.security.GeneralSecurityException;
michael@0: import java.util.ArrayList;
michael@0: import java.util.List;
michael@0: import java.util.concurrent.Executor;
michael@0: 
michael@0: import org.json.simple.JSONObject;
michael@0: import org.mozilla.gecko.background.common.log.Logger;
michael@0: import org.mozilla.gecko.background.fxa.SkewHandler;
michael@0: import org.mozilla.gecko.sync.ExtendedJSONObject;
michael@0: import org.mozilla.gecko.sync.NonArrayJSONException;
michael@0: import org.mozilla.gecko.sync.NonObjectJSONException;
michael@0: import org.mozilla.gecko.sync.UnexpectedJSONException.BadRequiredFieldJSONException;
michael@0: import org.mozilla.gecko.sync.net.AuthHeaderProvider;
michael@0: import org.mozilla.gecko.sync.net.BaseResource;
michael@0: import org.mozilla.gecko.sync.net.BaseResourceDelegate;
michael@0: import org.mozilla.gecko.sync.net.BrowserIDAuthHeaderProvider;
michael@0: import org.mozilla.gecko.sync.net.SyncResponse;
michael@0: import org.mozilla.gecko.tokenserver.TokenServerException.TokenServerConditionsRequiredException;
michael@0: import org.mozilla.gecko.tokenserver.TokenServerException.TokenServerInvalidCredentialsException;
michael@0: import org.mozilla.gecko.tokenserver.TokenServerException.TokenServerMalformedRequestException;
michael@0: import org.mozilla.gecko.tokenserver.TokenServerException.TokenServerMalformedResponseException;
michael@0: import org.mozilla.gecko.tokenserver.TokenServerException.TokenServerUnknownServiceException;
michael@0: 
michael@0: import ch.boye.httpclientandroidlib.Header;
michael@0: import ch.boye.httpclientandroidlib.HttpHeaders;
michael@0: import ch.boye.httpclientandroidlib.HttpResponse;
michael@0: import ch.boye.httpclientandroidlib.client.ClientProtocolException;
michael@0: import ch.boye.httpclientandroidlib.client.methods.HttpRequestBase;
michael@0: import ch.boye.httpclientandroidlib.impl.client.DefaultHttpClient;
michael@0: import ch.boye.httpclientandroidlib.message.BasicHeader;
michael@0: 
michael@0: /**
michael@0:  * HTTP client for interacting with the Mozilla Services Token Server API v1.0,
michael@0:  * as documented at
michael@0:  * <a href="http://docs.services.mozilla.com/token/apis.html">http://docs.services.mozilla.com/token/apis.html</a>.
michael@0:  * <p>
michael@0:  * A token server accepts some authorization credential and returns a different
michael@0:  * authorization credential. Usually, it used to exchange a public-key
michael@0:  * authorization token that is expensive to validate for a symmetric-key
michael@0:  * authorization that is cheap to validate. For example, we might exchange a
michael@0:  * BrowserID assertion for a HAWK id and key pair.
michael@0:  */
michael@0: public class TokenServerClient {
michael@0:   protected static final String LOG_TAG = "TokenServerClient";
michael@0: 
michael@0:   public static final String JSON_KEY_API_ENDPOINT = "api_endpoint";
michael@0:   public static final String JSON_KEY_CONDITION_URLS = "condition_urls";
michael@0:   public static final String JSON_KEY_DURATION = "duration";
michael@0:   public static final String JSON_KEY_ERRORS = "errors";
michael@0:   public static final String JSON_KEY_ID = "id";
michael@0:   public static final String JSON_KEY_KEY = "key";
michael@0:   public static final String JSON_KEY_UID = "uid";
michael@0: 
michael@0:   public static final String HEADER_CONDITIONS_ACCEPTED = "X-Conditions-Accepted";
michael@0:   public static final String HEADER_CLIENT_STATE = "X-Client-State";
michael@0: 
michael@0:   protected final Executor executor;
michael@0:   protected final URI uri;
michael@0: 
michael@0:   public TokenServerClient(URI uri, Executor executor) {
michael@0:     if (uri == null) {
michael@0:       throw new IllegalArgumentException("uri must not be null");
michael@0:     }
michael@0:     if (executor == null) {
michael@0:       throw new IllegalArgumentException("executor must not be null");
michael@0:     }
michael@0:     this.uri = uri;
michael@0:     this.executor = executor;
michael@0:   }
michael@0: 
michael@0:   protected void invokeHandleSuccess(final TokenServerClientDelegate delegate, final TokenServerToken token) {
michael@0:     executor.execute(new Runnable() {
michael@0:       @Override
michael@0:       public void run() {
michael@0:         delegate.handleSuccess(token);
michael@0:       }
michael@0:     });
michael@0:   }
michael@0: 
michael@0:   protected void invokeHandleFailure(final TokenServerClientDelegate delegate, final TokenServerException e) {
michael@0:     executor.execute(new Runnable() {
michael@0:       @Override
michael@0:       public void run() {
michael@0:         delegate.handleFailure(e);
michael@0:       }
michael@0:     });
michael@0:   }
michael@0: 
michael@0:   /**
michael@0:    * Notify the delegate that some kind of backoff header (X-Backoff,
michael@0:    * X-Weave-Backoff, Retry-After) was received and should be acted upon.
michael@0:    *
michael@0:    * This method is non-terminal, and will be followed by a separate
michael@0:    * <code>invoke*</code> call.
michael@0:    *
michael@0:    * @param delegate
michael@0:    *          the delegate to inform.
michael@0:    * @param backoffSeconds
michael@0:    *          the number of seconds for which the system should wait before
michael@0:    *          making another token server request to this server.
michael@0:    */
michael@0:   protected void notifyBackoff(final TokenServerClientDelegate delegate, final int backoffSeconds) {
michael@0:     executor.execute(new Runnable() {
michael@0:       @Override
michael@0:       public void run() {
michael@0:         delegate.handleBackoff(backoffSeconds);
michael@0:       }
michael@0:     });
michael@0:   }
michael@0: 
michael@0:   protected void invokeHandleError(final TokenServerClientDelegate delegate, final Exception e) {
michael@0:     executor.execute(new Runnable() {
michael@0:       @Override
michael@0:       public void run() {
michael@0:         delegate.handleError(e);
michael@0:       }
michael@0:     });
michael@0:   }
michael@0: 
michael@0:   public TokenServerToken processResponse(SyncResponse res) throws TokenServerException {
michael@0:     int statusCode = res.getStatusCode();
michael@0: 
michael@0:     Logger.debug(LOG_TAG, "Got token response with status code " + statusCode + ".");
michael@0: 
michael@0:     // Responses should *always* be JSON, even in the case of 4xx and 5xx
michael@0:     // errors. If we don't see JSON, the server is likely very unhappy.
michael@0:     final Header contentType = res.getContentType();
michael@0:     if (contentType == null) {
michael@0:       throw new TokenServerMalformedResponseException(null, "Non-JSON response Content-Type.");
michael@0:     }
michael@0: 
michael@0:     final String type = contentType.getValue();
michael@0:     if (!type.equals("application/json") &&
michael@0:         !type.startsWith("application/json;")) {
michael@0:       Logger.warn(LOG_TAG, "Got non-JSON response with Content-Type " +
michael@0:           contentType + ". Misconfigured server?");
michael@0:       throw new TokenServerMalformedResponseException(null, "Non-JSON response Content-Type.");
michael@0:     }
michael@0: 
michael@0:     // Responses should *always* be a valid JSON object.
michael@0:     // It turns out that right now they're not always, but that's a server bug...
michael@0:     ExtendedJSONObject result;
michael@0:     try {
michael@0:       result = res.jsonObjectBody();
michael@0:     } catch (Exception e) {
michael@0:       Logger.debug(LOG_TAG, "Malformed token response.", e);
michael@0:       throw new TokenServerMalformedResponseException(null, e);
michael@0:     }
michael@0: 
michael@0:     // The service shouldn't have any 3xx, so we don't need to handle those.
michael@0:     if (res.getStatusCode() != 200) {
michael@0:       // We should have a (Cornice) error report in the JSON. We log that to
michael@0:       // help with debugging.
michael@0:       List<ExtendedJSONObject> errorList = new ArrayList<ExtendedJSONObject>();
michael@0: 
michael@0:       if (result.containsKey(JSON_KEY_ERRORS)) {
michael@0:         try {
michael@0:           for (Object error : result.getArray(JSON_KEY_ERRORS)) {
michael@0:             Logger.warn(LOG_TAG, "" + error);
michael@0: 
michael@0:             if (error instanceof JSONObject) {
michael@0:               errorList.add(new ExtendedJSONObject((JSONObject) error));
michael@0:             }
michael@0:           }
michael@0:         } catch (NonArrayJSONException e) {
michael@0:           Logger.warn(LOG_TAG, "Got non-JSON array '" + result.getString(JSON_KEY_ERRORS) + "'.", e);
michael@0:         }
michael@0:       }
michael@0: 
michael@0:       if (statusCode == 400) {
michael@0:         throw new TokenServerMalformedRequestException(errorList, result.toJSONString());
michael@0:       }
michael@0: 
michael@0:       if (statusCode == 401) {
michael@0:         throw new TokenServerInvalidCredentialsException(errorList, result.toJSONString());
michael@0:       }
michael@0: 
michael@0:       // 403 should represent a "condition acceptance needed" response.
michael@0:       //
michael@0:       // The extra validation of "urls" is important. We don't want to signal
michael@0:       // conditions required unless we are absolutely sure that is what the
michael@0:       // server is asking for.
michael@0:       if (statusCode == 403) {
michael@0:         // Bug 792674 and Bug 783598: make this testing simpler. For now, we
michael@0:         // check that errors is an array, and take any condition_urls from the
michael@0:         // first element.
michael@0: 
michael@0:         try {
michael@0:           if (errorList == null || errorList.isEmpty()) {
michael@0:             throw new TokenServerMalformedResponseException(errorList, "403 response without proper fields.");
michael@0:           }
michael@0: 
michael@0:           ExtendedJSONObject error = errorList.get(0);
michael@0: 
michael@0:           ExtendedJSONObject condition_urls = error.getObject(JSON_KEY_CONDITION_URLS);
michael@0:           if (condition_urls != null) {
michael@0:             throw new TokenServerConditionsRequiredException(condition_urls);
michael@0:           }
michael@0:         } catch (NonObjectJSONException e) {
michael@0:           Logger.warn(LOG_TAG, "Got non-JSON error object.");
michael@0:         }
michael@0: 
michael@0:         throw new TokenServerMalformedResponseException(errorList, "403 response without proper fields.");
michael@0:       }
michael@0: 
michael@0:       if (statusCode == 404) {
michael@0:         throw new TokenServerUnknownServiceException(errorList);
michael@0:       }
michael@0: 
michael@0:       // We shouldn't ever get here...
michael@0:       throw new TokenServerException(errorList);
michael@0:     }
michael@0: 
michael@0:     try {
michael@0:       result.throwIfFieldsMissingOrMisTyped(new String[] { JSON_KEY_ID, JSON_KEY_KEY, JSON_KEY_API_ENDPOINT }, String.class);
michael@0:       result.throwIfFieldsMissingOrMisTyped(new String[] { JSON_KEY_UID }, Long.class);
michael@0:     } catch (BadRequiredFieldJSONException e ) {
michael@0:       throw new TokenServerMalformedResponseException(null, e);
michael@0:     }
michael@0: 
michael@0:     Logger.debug(LOG_TAG, "Successful token response: " + result.getString(JSON_KEY_ID));
michael@0: 
michael@0:     return new TokenServerToken(result.getString(JSON_KEY_ID),
michael@0:         result.getString(JSON_KEY_KEY),
michael@0:         result.get(JSON_KEY_UID).toString(),
michael@0:         result.getString(JSON_KEY_API_ENDPOINT));
michael@0:   }
michael@0: 
michael@0:   public static class TokenFetchResourceDelegate extends BaseResourceDelegate {
michael@0:     private final TokenServerClient         client;
michael@0:     private final TokenServerClientDelegate delegate;
michael@0:     private final String                    assertion;
michael@0:     private final String                    clientState;
michael@0:     private final BaseResource              resource;
michael@0:     private final boolean                   conditionsAccepted;
michael@0: 
michael@0:     public TokenFetchResourceDelegate(TokenServerClient client,
michael@0:                                       BaseResource resource,
michael@0:                                       TokenServerClientDelegate delegate,
michael@0:                                       String assertion, String clientState,
michael@0:                                       boolean conditionsAccepted) {
michael@0:       super(resource);
michael@0:       this.client = client;
michael@0:       this.delegate = delegate;
michael@0:       this.assertion = assertion;
michael@0:       this.clientState = clientState;
michael@0:       this.resource = resource;
michael@0:       this.conditionsAccepted = conditionsAccepted;
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public String getUserAgent() {
michael@0:       return delegate.getUserAgent();
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void handleHttpResponse(HttpResponse response) {
michael@0:       // Skew.
michael@0:       SkewHandler skewHandler = SkewHandler.getSkewHandlerForResource(resource);
michael@0:       skewHandler.updateSkew(response, System.currentTimeMillis());
michael@0: 
michael@0:       // Extract backoff regardless of whether this was an error response, and
michael@0:       // Retry-After for 503 responses. The error will be handled elsewhere.)
michael@0:       SyncResponse res = new SyncResponse(response);
michael@0:       final boolean includeRetryAfter = res.getStatusCode() == 503;
michael@0:       int backoffInSeconds = res.totalBackoffInSeconds(includeRetryAfter);
michael@0:       if (backoffInSeconds > -1) {
michael@0:         client.notifyBackoff(delegate, backoffInSeconds);
michael@0:       }
michael@0: 
michael@0:       try {
michael@0:         TokenServerToken token = client.processResponse(res);
michael@0:         client.invokeHandleSuccess(delegate, token);
michael@0:       } catch (TokenServerException e) {
michael@0:         client.invokeHandleFailure(delegate, e);
michael@0:       }
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void handleTransportException(GeneralSecurityException e) {
michael@0:       client.invokeHandleError(delegate, e);
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void handleHttpProtocolException(ClientProtocolException e) {
michael@0:       client.invokeHandleError(delegate, e);
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void handleHttpIOException(IOException e) {
michael@0:       client.invokeHandleError(delegate, e);
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public AuthHeaderProvider getAuthHeaderProvider() {
michael@0:       return new BrowserIDAuthHeaderProvider(assertion);
michael@0:     }
michael@0: 
michael@0:     @Override
michael@0:     public void addHeaders(HttpRequestBase request, DefaultHttpClient client) {
michael@0:       String host = request.getURI().getHost();
michael@0:       request.setHeader(new BasicHeader(HttpHeaders.HOST, host));
michael@0:       if (clientState != null) {
michael@0:         request.setHeader(new BasicHeader(HEADER_CLIENT_STATE, clientState));
michael@0:       }
michael@0:       if (conditionsAccepted) {
michael@0:         request.addHeader(HEADER_CONDITIONS_ACCEPTED, "1");
michael@0:       }
michael@0:     }
michael@0:   }
michael@0: 
michael@0:   public void getTokenFromBrowserIDAssertion(final String assertion,
michael@0:                                              final boolean conditionsAccepted,
michael@0:                                              final String clientState,
michael@0:                                              final TokenServerClientDelegate delegate) {
michael@0:     final BaseResource resource = new BaseResource(this.uri);
michael@0:     resource.delegate = new TokenFetchResourceDelegate(this, resource, delegate,
michael@0:                                                        assertion, clientState,
michael@0:                                                        conditionsAccepted);
michael@0:     resource.get();
michael@0:   }
michael@0: }