[Easy signin] Wire up userClick auth attempt to easy unlock app and back

chrome/browser/signin/easy_unlock_auth_attempt.h

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CHROME_BROWSER_SIGNIN_EASY_UNLOCK_AUTH_ATTEMPT_H_
+#define CHROME_BROWSER_SIGNIN_EASY_UNLOCK_AUTH_ATTEMPT_H_
+
+#include <string>
+
+#include "base/macros.h"
+
+class Profile;
+
+// Class responsible for handling easy unlock auth attempts (both for unlocking
+// the screen and logging in). The auth protocol is started by calling |Start|,
+// which notifies the easy unlock app about auth attempt. When the auth result
+// is available, |FinalizeUnlock| or |FinalizeSignin| should be called,
+// depending on auth type.
+// To cancel the in progress auth attempt, delete the |EasyUnlockAuthAttempt|
+// object.
+class EasyUnlockAuthAttempt {
+ public:
+  // The auth type.
+  enum Type {
+    TYPE_UNLOCK,
+    TYPE_SIGNIN
+  };
+
+  EasyUnlockAuthAttempt(Profile* profile,
+                        const std::string& user_id,
+                        Type type);
+  ~EasyUnlockAuthAttempt();
+
+  // Starts the auth attempt by sending screenlockPrivate.onAuthAttempted event
+  // to easy unlock app. Returns whether the event was successfully dispatched.
+  bool Start(const std::string& user_id);
+
+  // Finalizes an unlock attempt. It unlocks the screen if |success| is true.
+  // If |this| has TYPE_SIGNIN type, calling this method will cause signin
+  // failure equivalent to cancelling the attempt.
+  void FinalizeUnlock(const std::string& user_id, bool success);
+
+  // Finalizes signin attempt. It tries to log in using the secret derived from
+  // |wrapped_secret| decrypted by |session_key|. If the decryption fails, it
+  // fails the signin attempt.
+  // If called on an object with TYPE_UNLOCK type, it will cause unlock failure
+  // equivalent to cancelling the request.
+  void FinalizeSignin(const std::string& user_id,
+                      const std::string& wrapped_secret,
+                      const std::string& session_key);
+
+ private:
+  // The internal attempt state.
+  enum State {
+    STATE_IDLE,
+    STATE_RUNNING,
+    STATE_DONE
+  };
+
+  // Cancels the attempt.
+  void Cancel(const std::string& user_id);
+
+  Profile* profile_;
+  State state_;
+  std::string user_id_;
+  Type type_;
+
+  DISALLOW_COPY_AND_ASSIGN(EasyUnlockAuthAttempt);
+};
+
+#endif  // CHROME_BROWSER_SIGNIN_EASY_UNLOCK_AUTH_ATTEMPT_H_