Interface plus stub implementation for PrivetV3CryptoProvider

chrome/browser/local_discovery/privetv3_crypto_provider.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_LOCAL_DISCOVERY_PRIVETV3_CRYPTO_PROVIDER_H_
+#define CHROME_BROWSER_LOCAL_DISCOVERY_PRIVETV3_CRYPTO_PROVIDER_H_
+
+#include <string>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+
+namespace local_discovery {
+
+class PrivetV3CryptoProvider {
+ public:
+  enum HandshakeState {
+    // Handshake still in progress. Call |GetNextStep| to send next handshake
+    // step.
+    IN_PROGRESS,
+    // Handshake in progress, waiting for response. Call |SetStepResponse| to
+    // set the step response.
+    AWAITING_RESPONSE,
+    // Handshake in progress, need to wait for user verification to
+    // continue. Call |GetVerificationCode| to get the verification code and
+    // |AcceptVerificationCode| to signify the code is accepted.
+    AWAITING_USER_VERIFICATION,
+    // Handshake complete. Call |EncryptData| to encrypt the data.
+    HANDSHAKE_COMPLETE,
+    // Handshake error.
+    HANDSHAKE_ERROR
+  };
+
+  virtual ~PrivetV3CryptoProvider() {}
+
+  static scoped_ptr<PrivetV3CryptoProvider> Create(
+      const std::vector<std::string>& available_auth_methods);
+
+  // Return the current state of the crypto provider.
+  virtual HandshakeState GetState() = 0;
+
+  // Return the authentication method used.
+  virtual std::string GetAuthMethod() = 0;
+
+  // Get the next handshake command. |step| is the step number to send,
+  // |package| is a base64-encoded package to send with the step. Return
+  // |true| if a package is generated or |false| in case of an error.
+  virtual HandshakeState GetNextStep(int* step, std::string* package) = 0;
+
+  // Input the response to the handshake command. |step| is the received step
+  // number, |state| is the received state string, |package| is the received
+  // base64-encoded package. Return the current handshake state.
+  virtual HandshakeState SetStepResponse(int step,
+                                         const std::string& state,
+                                         const std::string& package) = 0;
+
+  // Get the verification code to be displayed on the screen.
+  virtual std::string GetVerificationCode() = 0;
+
+  // Signal that the verification code is accepted. Returns the current
+  // handshake state.
+  virtual HandshakeState AcceptVerificationCode() = 0;
+
+  // Encrypt a string using the session key.
+  virtual bool EncryptData(const std::string& input, std::string* output) = 0;
+};
+
+}  // namespace local_discovery
+
+#endif  // CHROME_BROWSER_LOCAL_DISCOVERY_PRIVETV3_CRYPTO_PROVIDER_H_