Add U2F request state machines

device/u2f/u2f_sign.h

Index: device/u2f/u2f_sign.h
diff --git a/device/u2f/u2f_sign.h b/device/u2f/u2f_sign.h
new file mode 100644
index 0000000000000000000000000000000000000000..e924137f81324e3a4d4ba05eafa602152379eac0
--- /dev/null
+++ b/device/u2f/u2f_sign.h
@@ -0,0 +1,51 @@
+// Copyright 2017 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 DEVICE_U2F_U2F_SIGN_H_
+#define DEVICE_U2F_U2F_SIGN_H_
+
+#include <vector>
+
+#include "u2f_request.h"
+
+namespace device {
+
+class U2fSign : public U2fRequest {
+ public:
+  U2fSign(const std::vector<std::vector<uint8_t>>& registered_keys,
+          const std::vector<uint8_t>& challenge_hash,
+          const std::vector<uint8_t>& app_param,
+          const ResponseCallback& cb);
+  ~U2fSign() override;
+
+  static std::unique_ptr<U2fRequest> TrySign(
+      const std::vector<std::vector<uint8_t>>& registered_keys,
+      const std::vector<uint8_t>& challenge_hash,
+      const std::vector<uint8_t>& app_param,
+      const ResponseCallback& cb);
+
+ private:
+  void TryDevice() override;
+  void OnTryDevice(std::vector<std::vector<uint8_t>>::const_iterator,
+                   U2fReturnCode,
+                   std::vector<uint8_t>);

[Reilly Grant (use Gerrit), 2017/04/22 00:16:43]

nit (for a later patch): MessageCallback should take a const
std::vector<uint8_t>&.

[Casey Piper, 2017/04/22 00:50:08]

Acknowledged.

+
+  const std::vector<std::vector<uint8_t>> registered_keys_;
+  std::vector<uint8_t> challenge_hash_;
+  std::vector<uint8_t> app_param_;
+  const std::vector<uint8_t> kBogusAppParam = {
+      0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41,
+      0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41,
+      0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41};
+  const std::vector<uint8_t> kBogusChallenge = {
+      0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42,
+      0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42,
+      0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42, 0x42};
+
+  base::WeakPtrFactory<U2fSign> weak_factory_;
+};
+
+}  // namespace device
+
+#endif  // DEVICE_U2F_U2F_SIGN_H_