Add the possibility to export private view key for fast scan.

On client startup the device asks for authorization to export the private view key.
If user agree, the client hold the private view key allowing a fast blockchain scan.
If the user does not agree, the blockchain scan is fully done via the device.

1 files changed, 16 insertions, 6 deletions

diff --git a/src/device/device.hpp b/src/device/device.hpp
index dee191234..db489ff0c 100644
--- a/src/device/device.hpp
+++ b/src/device/device.hpp
@@ -78,6 +78,7 @@ namespace hw {
            return false;
     }
 
+
     class device {
     protected:
         std::string  name;
@@ -89,10 +90,12 @@ namespace hw {
         virtual ~device()   {}
 
         explicit virtual operator bool() const = 0;
-
-        static const int SIGNATURE_REAL = 0;
-        static const int SIGNATURE_FAKE = 1;
-
+        enum device_mode {
+            NONE,
+            TRANSACTION_CREATE_REAL,
+            TRANSACTION_CREATE_FAKE,
+            TRANSACTION_PARSE
+        };
 
         /* ======================================================================= */
         /*                              SETUP/TEARDOWN                             */
@@ -106,6 +109,9 @@ namespace hw {
         virtual bool connect(void) = 0;
         virtual bool disconnect(void) = 0;
 
+        virtual bool  set_mode(device_mode mode) = 0;
+
+
         /* ======================================================================= */
         /*  LOCKER                                                                 */
         /* ======================================================================= */ 
@@ -166,8 +172,6 @@ namespace hw {
 
         virtual bool  open_tx(crypto::secret_key &tx_key) = 0;
 
-        virtual bool  set_signature_mode(unsigned int sig_mode) = 0;
-
         virtual bool  encrypt_payment_id(crypto::hash8 &payment_id, const crypto::public_key &public_key, const crypto::secret_key &secret_key) = 0;
         bool  decrypt_payment_id(crypto::hash8 &payment_id, const crypto::public_key &public_key, const crypto::secret_key &secret_key)
         {
@@ -191,6 +195,12 @@ namespace hw {
         virtual bool  close_tx(void) = 0;
     } ;
 
+    struct reset_mode {
+        device& hwref;
+        reset_mode(hw::device& dev) : hwref(dev) { }
+        ~reset_mode() { hwref.set_mode(hw::device::NONE);}
+    };
+
     device& get_device(const std::string device_descriptor) ;
 }