Merge pull request #3536

c77d2bfa Add the possibility to export private view key for fast scan. (cslashm)
100b7bc1 Change mutex lock model to avoid dead lock and ensure locks are always released. (cslashm)
641dfc99 Automatic height setup when creating/restoring hw device. (cslashm)

8 files changed, 413 insertions, 473 deletions

diff --git a/src/device/device.hpp b/src/device/device.hpp
index b47460472..db489ff0c 100644
--- a/src/device/device.hpp
+++ b/src/device/device.hpp
@@ -80,6 +80,9 @@ namespace hw {
 
 
     class device {
+    protected:
+        std::string  name;
+
     public:
 
         device()  {}
@@ -87,12 +90,12 @@ namespace hw {
         virtual ~device()   {}
 
         explicit virtual operator bool() const = 0;
-
-        static const int SIGNATURE_REAL = 0;
-        static const int SIGNATURE_FAKE = 1;
-
-
-        std::string  name;
+        enum device_mode {
+            NONE,
+            TRANSACTION_CREATE_REAL,
+            TRANSACTION_CREATE_FAKE,
+            TRANSACTION_PARSE
+        };
 
         /* ======================================================================= */
         /*                              SETUP/TEARDOWN                             */
@@ -104,7 +107,18 @@ namespace hw {
         virtual bool release() = 0;
 
         virtual bool connect(void) = 0;
-        virtual bool disconnect() = 0;
+        virtual bool disconnect(void) = 0;
+
+        virtual bool  set_mode(device_mode mode) = 0;
+
+
+        /* ======================================================================= */
+        /*  LOCKER                                                                 */
+        /* ======================================================================= */ 
+        virtual void lock(void) = 0;
+        virtual void unlock(void) = 0;
+        virtual bool try_lock(void) = 0;
+
 
         /* ======================================================================= */
         /*                             WALLET & ADDRESS                            */
@@ -158,8 +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)
         {
@@ -183,6 +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) ;
 }
 
diff --git a/src/device/device_default.cpp b/src/device/device_default.cpp
index d63dafe9e..96838a289 100644
--- a/src/device/device_default.cpp
+++ b/src/device/device_default.cpp
@@ -81,6 +81,20 @@ namespace hw {
             dfns();
         }
 
+        bool  device_default::set_mode(device_mode mode) {
+            return true;
+        }
+
+        /* ======================================================================= */
+        /*  LOCKER                                                                 */
+        /* ======================================================================= */ 
+    
+        void device_default::lock() { }
+
+        bool device_default::try_lock() { return true; }
+
+        void device_default::unlock() { }
+
         /* ======================================================================= */
         /*                             WALLET & ADDRESS                            */
         /* ======================================================================= */
@@ -262,10 +276,6 @@ namespace hw {
             return true;
         }
 
-        bool  device_default::set_signature_mode(unsigned int sig_mode) {
-            return true;
-        }
-
         bool  device_default::encrypt_payment_id(crypto::hash8 &payment_id, const crypto::public_key &public_key, const crypto::secret_key &secret_key) {
             crypto::key_derivation derivation;
             crypto::hash hash;
diff --git a/src/device/device_default.hpp b/src/device/device_default.hpp
index 02faeba0c..53942f53a 100644
--- a/src/device/device_default.hpp
+++ b/src/device/device_default.hpp
@@ -58,8 +58,17 @@ namespace hw {
 
             bool connect(void) override;
             bool disconnect() override;
+ 
+            bool set_mode(device_mode mode) override;
 
             /* ======================================================================= */
+            /*  LOCKER                                                                 */
+            /* ======================================================================= */ 
+            void lock(void)  override;
+            void unlock(void) override;
+            bool try_lock(void) override;
+            
+            /* ======================================================================= */
             /*                             WALLET & ADDRESS                            */
             /* ======================================================================= */
             bool  get_public_address(cryptonote::account_public_address &pubkey) override;
@@ -97,9 +106,6 @@ namespace hw {
 
             bool  open_tx(crypto::secret_key &tx_key) override;
 
-            //bool  get_additional_key(const bool subaddr, cryptonote::keypair &additional_txkey) override;
-            bool  set_signature_mode(unsigned int sig_mode) override;
-
             bool  encrypt_payment_id(crypto::hash8 &payment_id, const crypto::public_key &public_key, const crypto::secret_key &secret_key) override;
 
             bool  ecdhEncode(rct::ecdhTuple & unmasked, const rct::key & sharedSec) override;
diff --git a/src/device/device_ledger.cpp b/src/device/device_ledger.cpp
index b3c0035a1..ee1497438 100644
--- a/src/device/device_ledger.cpp
+++ b/src/device/device_ledger.cpp
@@ -33,7 +33,8 @@
 #include "cryptonote_basic/account.h"
 #include "cryptonote_basic/subaddress_index.h"
 
-
+#include <boost/thread/locks.hpp> 
+#include <boost/thread/lock_guard.hpp>
 
 namespace hw {
 
@@ -57,8 +58,8 @@ namespace hw {
     #define ASSERT_T0(exp)       CHECK_AND_ASSERT_THROW_MES(exp, "Protocol assert failure: "#exp ) ;
 
     #ifdef DEBUG_HWDEVICE
-      crypto::secret_key viewkey;
-      crypto::secret_key spendkey;
+      crypto::secret_key dbg_viewkey;
+      crypto::secret_key dbg_spendkey;
     #endif
 
     /* ===================================================================== */
@@ -118,7 +119,14 @@ namespace hw {
     #endif
 
     /* ===================================================================== */
-    /* ===                         Device                               ==== */
+    /* ===                       Internal Helpers                       ==== */
+    /* ===================================================================== */
+    static bool is_fake_view_key(const crypto::secret_key &sec) {
+      return sec == crypto::null_skey;
+    }
+
+    /* ===================================================================== */
+    /* ===                             Device                           ==== */
     /* ===================================================================== */
 
     static int device_id = 0;
@@ -196,6 +204,8 @@ namespace hw {
       this->hCard   = 0;
       this->hContext = 0;
       this->reset_buffer();      
+      this->mode = NONE;
+      this->has_view_key = false;
       MDEBUG( "Device "<<this->id <<" Created");
     }
 
@@ -204,14 +214,51 @@ namespace hw {
       MDEBUG( "Device "<<this->id <<" Destroyed");
     }
 
+    /* ======================================================================= */
+    /*  LOCKER                                                                 */
+    /* ======================================================================= */ 
+    
+    //automatic lock one more level on device ensuring the current thread is allowed to use it
+    #define AUTO_LOCK_CMD() \
+      /* lock both mutexes without deadlock*/ \
+      boost::lock(device_locker, command_locker); \
+      /* make sure both already-locked mutexes are unlocked at the end of scope */ \
+      boost::lock_guard<boost::recursive_mutex> lock1(device_locker, boost::adopt_lock); \
+      boost::lock_guard<boost::mutex> lock2(command_locker, boost::adopt_lock)
+
+    //lock the device for a long sequence
+    void device_ledger::lock(void) {
+      MDEBUG( "Ask for LOCKING for device "<<this->name << " in thread ");
+      device_locker.lock();
+      MDEBUG( "Device "<<this->name << " LOCKed");
+    }
+
+    //lock the device for a long sequence
+    bool device_ledger::try_lock(void) {
+      MDEBUG( "Ask for LOCKING(try) for device "<<this->name << " in thread ");
+      bool r = device_locker.try_lock();
+      if (r) {
+        MDEBUG( "Device "<<this->name << " LOCKed(try)");
+      } else {
+        MDEBUG( "Device "<<this->name << " not LOCKed(try)");
+      }
+      return r;
+    }
+
+    //lock the device for a long sequence
+    void device_ledger::unlock(void) {
+      try {
+        MDEBUG( "Ask for UNLOCKING for device "<<this->name << " in thread ");
+      } catch (...) {
+      }
+      device_locker.unlock();
+      MDEBUG( "Device "<<this->name << " UNLOCKed");
+    }
 
     /* ======================================================================= */
     /*                                   MISC                                  */
     /* ======================================================================= */
     bool device_ledger::reset() {
-
-      lock_device();
-      try {
         int offset;
         reset_buffer();
 
@@ -227,12 +274,7 @@ namespace hw {
         this->buffer_send[4] = offset-5;
         this->length_send = offset;
         this->exchange();
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
      
     unsigned int device_ledger::exchange(unsigned int ok, unsigned int mask) {
@@ -261,30 +303,6 @@ namespace hw {
       memset(this->buffer_recv, 0, BUFFER_RECV_SIZE);
     }
 
-    void device_ledger::lock_device()   {
-      MDEBUG( "Ask for LOCKING for device "<<this->id);
-      device_locker.lock();
-      MDEBUG( "Device "<<this->id << " LOCKed");
-    }
-    void device_ledger::unlock_device() {
-      try {
-        MDEBUG( "Ask for UNLOCKING for device "<<this->id);
-      } catch (...) {
-      }
-      device_locker.unlock();
-      MDEBUG( "Device "<<this->id << " UNLOCKed");
-    }
-    void device_ledger::lock_tx()       {
-      MDEBUG( "Ask for LOCKING for TX "<<this->id);
-      //tx_locker.lock();
-      MDEBUG( "TX "<<this->id << " LOCKed");
-    }
-    void device_ledger::unlock_tx()     {
-      MDEBUG( "Ask for UNLOCKING for TX "<<this->id);
-      //tx_locker.unlock();
-      MDEBUG( "TX "<<this->id << " UNLOCKed");
-    }
-
     /* ======================================================================= */
     /*                              SETUP/TEARDOWN                             */
     /* ======================================================================= */
@@ -394,10 +412,10 @@ namespace hw {
       #ifdef DEBUG_HWDEVICE
       cryptonote::account_public_address pubkey;
       this->get_public_address(pubkey);
+      #endif
       crypto::secret_key vkey;
       crypto::secret_key skey;
       this->get_secret_keys(vkey,skey);
-      #endif
 
       return rv==SCARD_S_SUCCESS;
     }
@@ -411,16 +429,55 @@ namespace hw {
       return true;
     }
 
+    bool  device_ledger::set_mode(device_mode mode) {
+        AUTO_LOCK_CMD();
+
+        int offset;
+
+        reset_buffer();
+
+        switch(mode) {
+        case TRANSACTION_CREATE_REAL:
+        case TRANSACTION_CREATE_FAKE:
+          this->buffer_send[0] = 0x00;
+          this->buffer_send[1] = INS_SET_SIGNATURE_MODE;
+          this->buffer_send[2] = 0x01;
+          this->buffer_send[3] = 0x00;
+          this->buffer_send[4] = 0x00;
+          offset = 5;
+          //options
+          this->buffer_send[offset] = 0x00;
+          offset += 1;
+          //account
+          this->buffer_send[offset] = mode;
+          offset += 1;
+
+          this->buffer_send[4] = offset-5;
+          this->length_send = offset;
+          this->exchange();
+
+          this->mode = mode;
+          break;
+
+        case TRANSACTION_PARSE: 
+        case NONE:
+          this->mode = mode;
+          break;
+        default:
+           CHECK_AND_ASSERT_THROW_MES(false, " device_ledger::set_mode(unsigned int mode): invalid mode: "<<mode);
+        }
+        MDEBUG("Switch to mode: " <<mode);
+        return true;
+    }
+
 
     /* ======================================================================= */
     /*                             WALLET & ADDRESS                            */
     /* ======================================================================= */
 
-    /* Application API */
      bool device_ledger::get_public_address(cryptonote::account_public_address &pubkey){
+        AUTO_LOCK_CMD();
 
-      lock_device();
-      try {
         int offset;
         reset_buffer();
 
@@ -440,21 +497,17 @@ namespace hw {
 
         memmove(pubkey.m_view_public_key.data, this->buffer_recv, 32);
         memmove(pubkey.m_spend_public_key.data, this->buffer_recv+32, 32);
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+ 
+        return true;
     }
 
-    bool  device_ledger::get_secret_keys(crypto::secret_key &viewkey , crypto::secret_key &spendkey) {
-      memset(viewkey.data, 0x00, 32);
-      memset(spendkey.data, 0xFF, 32);
+    bool  device_ledger::get_secret_keys(crypto::secret_key &vkey , crypto::secret_key &skey) {
+        AUTO_LOCK_CMD();
+
+        //secret key are represented as fake key on the wallet side
+        memset(vkey.data, 0x00, 32);
+        memset(skey.data, 0xFF, 32);
 
-      #ifdef DEBUG_HWDEVICE
-      lock_device();
-      try {
         //spcialkey, normal conf handled in decrypt
         int offset;
         reset_buffer();
@@ -473,21 +526,26 @@ namespace hw {
         this->length_send = offset;
         this->exchange();
 
-        //clear key
-        memmove(ledger::viewkey.data,  this->buffer_recv+64, 32);
-        memmove(ledger::spendkey.data, this->buffer_recv+96, 32);
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      #endif
-      return true;
+        //View key is retrievied, if allowed, to speed up blockchain parsing
+        memmove(this->viewkey.data,  this->buffer_recv+0,  32);
+        if (is_fake_view_key(this->viewkey)) {
+          MDEBUG("Have Not view key");
+          this->has_view_key = false;
+        } else {
+          MDEBUG("Have view key");
+          this->has_view_key = true;
+        }
+      
+        #ifdef DEBUG_HWDEVICE
+        memmove(dbg_viewkey.data, this->buffer_recv+0, 32);
+        memmove(dbg_spendkey.data, this->buffer_recv+32, 32);
+        #endif
+
+        return true;
     }
 
     bool  device_ledger::generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key) {
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         int offset;
 
         #ifdef DEBUG_HWDEVICE
@@ -519,11 +577,6 @@ namespace hw {
         hw::ledger::check32("generate_chacha_key_prehashed", "key", (char*)key_x.data(), (char*)key.data());
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
       return true;
     }
 
@@ -532,15 +585,15 @@ namespace hw {
     /* ======================================================================= */
 
     bool device_ledger::derive_subaddress_public_key(const crypto::public_key &pub, const crypto::key_derivation &derivation, const std::size_t output_index, crypto::public_key &derived_pub){
-
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
-
+        AUTO_LOCK_CMD();
         #ifdef DEBUG_HWDEVICE
         const crypto::public_key pub_x = pub;
-        const crypto::key_derivation derivation_x  = hw::ledger::decrypt(derivation);
+        crypto::key_derivation derivation_x;
+         if ((this->mode == TRANSACTION_PARSE) && has_view_key) {    
+          derivation_x = derivation;
+        } else {
+          derivation_x = hw::ledger::decrypt(derivation);
+        }
         const std::size_t output_index_x = output_index;
         crypto::public_key derived_pub_x;
         hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  pub       ", pub_x.data, 32);
@@ -550,10 +603,17 @@ namespace hw {
         hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[OUT]] derived_pub", derived_pub_x.data, 32);
         #endif
 
+      if ((this->mode == TRANSACTION_PARSE) && has_view_key) {     
+        //If we are in TRANSACTION_PARSE, the given derivation has been retrieved uncrypted (wihtout the help
+        //of the device), so continue that way.
+        MDEBUG( "derive_subaddress_public_key  : PARSE mode with known viewkey");     
+        crypto::derive_subaddress_public_key(pub, derivation, output_index,derived_pub);
+      } else {
+       
+        int offset =0;
+ 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_DERIVE_SUBADDRESS_PUBLIC_KEY;
         this->buffer_send[2] = 0x00;
@@ -561,7 +621,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //pub
         memmove(this->buffer_send+offset, pub.data, 32);
@@ -582,34 +642,27 @@ namespace hw {
 
         //pub key
         memmove(derived_pub.data, &this->buffer_recv[0], 32);
-
-        #ifdef DEBUG_HWDEVICE
-        hw::ledger::check32("derive_subaddress_public_key", "derived_pub", derived_pub_x.data, derived_pub.data);
-        #endif
-
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
       }
+      #ifdef DEBUG_HWDEVICE
+      hw::ledger::check32("derive_subaddress_public_key", "derived_pub", derived_pub_x.data, derived_pub.data);
+      #endif
+
       return true;
     }
 
     crypto::public_key device_ledger::get_subaddress_spend_public_key(const cryptonote::account_keys& keys, const cryptonote::subaddress_index &index) {
-      crypto::public_key D;
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        crypto::public_key D;
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const cryptonote::account_keys     keys_x =  hw::ledger::decrypt(keys);
         const cryptonote::subaddress_index index_x = index;
         crypto::public_key                 D_x;
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_view_secret_key ", keys_x.m_view_secret_key.data,32);
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_spend_secret_key", keys_x.m_spend_secret_key.data,32);
+        hw::ledger::log_hexbuffer("get_subaddress_spend_public_key: [[IN]]  keys.m_view_secret_key ", keys_x.m_view_secret_key.data,32);
+        hw::ledger::log_hexbuffer("get_subaddress_spend_public_key: [[IN]]  keys.m_spend_secret_key", keys_x.m_spend_secret_key.data,32);
         hw::ledger::log_message  ("get_subaddress_spend_public_key: [[IN]]  index               ", std::to_string(index_x.major)+"."+std::to_string(index_x.minor));
-        this->controle_device->get_subaddress_spend_public_key(keys_x, index_x, D_x);
+        D_x = this->controle_device->get_subaddress_spend_public_key(keys_x, index_x);
         hw::ledger::log_hexbuffer("get_subaddress_spend_public_key: [[OUT]] derivation          ", D_x.data, 32);
         #endif
 
@@ -644,12 +697,7 @@ namespace hw {
         hw::ledger::check32("get_subaddress_spend_public_key", "D", D_x.data, D.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return D;
+        return D;
     }
 
     std::vector<crypto::public_key>  device_ledger::get_subaddress_spend_public_keys(const cryptonote::account_keys &keys, uint32_t account, uint32_t begin, uint32_t end) {
@@ -665,24 +713,22 @@ namespace hw {
     }
 
     cryptonote::account_public_address device_ledger::get_subaddress(const cryptonote::account_keys& keys, const cryptonote::subaddress_index &index) {
-      cryptonote::account_public_address address;
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        cryptonote::account_public_address address;
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const cryptonote::account_keys            keys_x =  hw::ledger::decrypt(keys);
         const cryptonote::subaddress_index        index_x = index;
         cryptonote::account_public_address  address_x;
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_view_secret_key ", keys_x.m_view_secret_key.data, 32);
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_view_public_key",  keys_x.m_account_address.m_view_public_key.data, 32);
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_view_secret_key ", keys_x.m_view_secret_key.data, 32);
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_spend_public_key", keys_x.m_account_address.m_spend_public_key.data, 32);
+        hw::ledger::log_hexbuffer("get_subaddress: [[IN]]  keys.m_view_secret_key ", keys_x.m_view_secret_key.data, 32);
+        hw::ledger::log_hexbuffer("get_subaddress: [[IN]]  keys.m_view_public_key",  keys_x.m_account_address.m_view_public_key.data, 32);
+        hw::ledger::log_hexbuffer("get_subaddress: [[IN]]  keys.m_view_secret_key ", keys_x.m_view_secret_key.data, 32);
+        hw::ledger::log_hexbuffer("get_subaddress: [[IN]]  keys.m_spend_public_key", keys_x.m_account_address.m_spend_public_key.data, 32);
         hw::ledger::log_message  ("get_subaddress: [[IN]]  index                                ", std::to_string(index_x.major)+"."+std::to_string(index_x.minor));
-        this->controle_device->get_subaddress(keys_x, index_x, address_x);
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_view_public_key ", address_x.m_view_public_key.data, 32);
-        hw::ledger::log_hexbuffer("derive_subaddress_public_key: [[IN]]  keys.m_spend_public_key", address_x.m_spend_public_key.data, 32);
+        address_x = this->controle_device->get_subaddress(keys_x, index_x);
+        hw::ledger::log_hexbuffer("get_subaddress: [[OUT]]  keys.m_view_public_key ", address_x.m_view_public_key.data, 32);
+        hw::ledger::log_hexbuffer("get_subaddress: [[OUT]]  keys.m_spend_public_key", address_x.m_spend_public_key.data, 32);
         #endif
 
         if (index.is_zero()) {
@@ -717,20 +763,13 @@ namespace hw {
         hw::ledger::check32("get_subaddress", "address.m_spend_public_key.data", address_x.m_spend_public_key.data, address.m_spend_public_key.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return address;
+        return address;
     }
 
     crypto::secret_key  device_ledger::get_subaddress_secret_key(const crypto::secret_key &sec, const cryptonote::subaddress_index &index) {
-      crypto::secret_key sub_sec;
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        crypto::secret_key sub_sec;
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::secret_key            sec_x =  hw::ledger::decrypt(sec);
@@ -738,7 +777,7 @@ namespace hw {
         crypto::secret_key            sub_sec_x;
         hw::ledger::log_message  ("get_subaddress_secret_key: [[IN]]  index  ", std::to_string(index.major)+"."+std::to_string(index.minor));
         hw::ledger::log_hexbuffer("get_subaddress_secret_key: [[IN]]  sec    ", sec_x.data, 32);
-        this->controle_device->get_subaddress_secret_key(sec_x, index_x, sub_sec_x);
+        sub_sec_x = this->controle_device->get_subaddress_secret_key(sec_x, index_x);
         hw::ledger::log_hexbuffer("get_subaddress_secret_key: [[OUT]] sub_sec", sub_sec_x.data, 32);
         #endif
 
@@ -751,7 +790,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //sec
         memmove(this->buffer_send+offset, sec.data, 32);
@@ -772,12 +811,7 @@ namespace hw {
         hw::ledger::check32("get_subaddress_secret_key", "sub_sec", sub_sec_x.data, sub_sec_clear.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return sub_sec;
+        return sub_sec;
     }
 
     /* ======================================================================= */
@@ -785,10 +819,9 @@ namespace hw {
     /* ======================================================================= */
 
     bool  device_ledger::verify_keys(const crypto::secret_key &secret_key, const crypto::public_key &public_key) {
-      lock_device();
-      try {
-        int offset =0,sw;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset, sw;
+
         reset_buffer();
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_VERIFY_KEY;
@@ -816,20 +849,12 @@ namespace hw {
           this->buffer_recv[2] << 8  |
           this->buffer_recv[3] << 0  ;
 
-        unlock_device();
         return verified == 1;
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return false;
     }
 
     bool device_ledger::scalarmultKey(rct::key & aP, const rct::key &P, const rct::key &a) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const rct::key P_x    =  P;
@@ -843,8 +868,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_SECRET_SCAL_MUL_KEY;
         this->buffer_send[2] = 0x00;
@@ -852,7 +875,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //pub
         memmove(this->buffer_send+offset, P.bytes, 32);
@@ -873,19 +896,12 @@ namespace hw {
         hw::ledger::check32("scalarmultKey", "mulkey", (char*)aP_x.bytes, (char*)aP.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::scalarmultBase(rct::key &aG, const rct::key &a) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const rct::key a_x    =  hw::ledger::decrypt(a);
@@ -897,8 +913,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_SECRET_SCAL_MUL_BASE;
         this->buffer_send[2] = 0x00;
@@ -906,7 +920,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //sec
         memmove(this->buffer_send+offset, a.bytes, 32);
@@ -923,20 +937,12 @@ namespace hw {
         hw::ledger::check32("scalarmultBase", "mulkey", (char*)aG_x.bytes, (char*)aG.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::sc_secret_add( crypto::secret_key &r, const crypto::secret_key &a, const crypto::secret_key &b) {
-
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::secret_key a_x = hw::ledger::decrypt(a);
@@ -947,8 +953,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_SECRET_KEY_ADD;
         this->buffer_send[2] = 0x00;
@@ -956,7 +960,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //sec key
         memmove(this->buffer_send+offset, a.data, 32);
@@ -977,23 +981,16 @@ namespace hw {
         hw::ledger::check32("sc_secret_add", "r", r_x.data, r_clear.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     crypto::secret_key  device_ledger::generate_keys(crypto::public_key &pub, crypto::secret_key &sec, const crypto::secret_key& recovery_key, bool recover) {
-      if (recover) {
-        throw std::runtime_error("device generate key does not support recover");
-      }
+        AUTO_LOCK_CMD();
+        if (recover) {
+           throw std::runtime_error("device generate key does not support recover");
+        }
 
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         bool recover_x = recover;
@@ -1004,8 +1001,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_GENERATE_KEYPAIR;
         this->buffer_send[2] = 0x00;
@@ -1013,7 +1008,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
 
         this->buffer_send[4] = offset-5;
@@ -1031,20 +1026,13 @@ namespace hw {
         hw::ledger::check32("generate_keys", "pub", pub_x.data, pub.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return sec;
+        return sec;
 
     }
 
     bool device_ledger::generate_key_derivation(const crypto::public_key &pub, const crypto::secret_key &sec, crypto::key_derivation &derivation) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        bool r = false;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::public_key pub_x = pub;
@@ -1056,6 +1044,17 @@ namespace hw {
         hw::ledger::log_hexbuffer("generate_key_derivation: [[OUT]] derivation", derivation_x.data, 32);
         #endif
 
+      if ((this->mode == TRANSACTION_PARSE)  && has_view_key) {
+        //A derivation is resquested in PASRE mode and we have the view key,
+        //so do that wihtout the device and return the derivation unencrypted.
+        MDEBUG( "generate_key_derivation  : PARSE mode with known viewkey");     
+        //Note derivation in PARSE mode can only happen with viewkey, so assert it!
+        assert(is_fake_view_key(sec));
+        r = crypto::generate_key_derivation(pub, this->viewkey, derivation);
+      } else {
+
+        int offset;
+
         reset_buffer();
 
         this->buffer_send[0] = 0x00;
@@ -1065,7 +1064,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //pub
         memmove(this->buffer_send+offset, pub.data, 32);
@@ -1080,25 +1079,24 @@ namespace hw {
 
         //derivattion data
         memmove(derivation.data, &this->buffer_recv[0], 32);
-
-        #ifdef DEBUG_HWDEVICE
-        crypto::key_derivation derivation_clear  = hw::ledger::decrypt(derivation);
-        hw::ledger::check32("generate_key_derivation", "derivation", derivation_x.data, derivation_clear.data);
-        #endif
-
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
+        r = true;
       }
-      return true;
+      #ifdef DEBUG_HWDEVICE
+      crypto::key_derivation derivation_clear ;
+        if ((this->mode == TRANSACTION_PARSE)  && has_view_key) {
+          derivation_clear  = derivation;
+        }else {
+          derivation_clear  = hw::ledger::decrypt(derivation);
+        }
+      hw::ledger::check32("generate_key_derivation", "derivation", derivation_x.data, derivation_clear.data);
+      #endif
+
+      return r;
     }
 
     bool device_ledger::derivation_to_scalar(const crypto::key_derivation &derivation, const size_t output_index, crypto::ec_scalar &res) {
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         int offset;
-        unsigned char options;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::key_derivation derivation_x = hw::ledger::decrypt(derivation);
@@ -1112,8 +1110,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_DERIVATION_TO_SCALAR;
         this->buffer_send[2] = 0x00;
@@ -1121,7 +1117,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //derivattion
         memmove(this->buffer_send+offset, derivation.data, 32);
@@ -1145,19 +1141,12 @@ namespace hw {
         hw::ledger::check32("derivation_to_scalar", "res", res_x.data, res_clear.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::derive_secret_key(const crypto::key_derivation &derivation, const std::size_t output_index, const crypto::secret_key &sec, crypto::secret_key &derived_sec) {
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         int offset;
-        unsigned char options;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::key_derivation derivation_x   = hw::ledger::decrypt(derivation);
@@ -1173,8 +1162,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_DERIVE_SECRET_KEY;
         this->buffer_send[2] = 0x00;
@@ -1182,7 +1169,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //derivation
         memmove(this->buffer_send+offset, derivation.data, 32);
@@ -1209,20 +1196,13 @@ namespace hw {
         hw::ledger::check32("derive_secret_key", "derived_sec", derived_sec_x.data, derived_sec_clear.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::derive_public_key(const crypto::key_derivation &derivation, const std::size_t output_index, const crypto::public_key &pub, crypto::public_key &derived_pub){
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         int offset;
-        unsigned char options;
-
+      
         #ifdef DEBUG_HWDEVICE
         const crypto::key_derivation derivation_x   = hw::ledger::decrypt(derivation);
         const std::size_t            output_index_x = output_index;
@@ -1237,8 +1217,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_DERIVE_PUBLIC_KEY;
         this->buffer_send[2] = 0x00;
@@ -1246,7 +1224,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //derivation
         memmove(this->buffer_send+offset, derivation.data, 32);
@@ -1272,19 +1250,12 @@ namespace hw {
         hw::ledger::check32("derive_public_key", "derived_pub", derived_pub_x.data, derived_pub.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::secret_key_to_public_key(const crypto::secret_key &sec, crypto::public_key &pub) {
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         int offset;
-        unsigned char options;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::secret_key sec_x = hw::ledger::decrypt(sec);
@@ -1299,8 +1270,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_SECRET_KEY_TO_PUBLIC_KEY;
         this->buffer_send[2] = 0x00;
@@ -1308,7 +1277,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //sec key
         memmove(this->buffer_send+offset, sec.data, 32);
@@ -1325,19 +1294,12 @@ namespace hw {
         hw::ledger::check32("secret_key_to_public_key", "pub", pub_x.data, pub.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::generate_key_image(const crypto::public_key &pub, const crypto::secret_key &sec, crypto::key_image &image){
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         int offset;
-        unsigned char options;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::public_key pub_x = pub;
@@ -1351,8 +1313,6 @@ namespace hw {
 
         reset_buffer();
 
-        options = 0;
-
         this->buffer_send[0] = 0x00;
         this->buffer_send[1] = INS_GEN_KEY_IMAGE;
         this->buffer_send[2] = 0x00;
@@ -1360,7 +1320,7 @@ namespace hw {
         this->buffer_send[4] = 0x00;
         offset = 5;
         //options
-        this->buffer_send[offset] = options;
+        this->buffer_send[offset] = 0;
         offset += 1;
         //pub
         memmove(this->buffer_send+offset, pub.data, 32);
@@ -1380,12 +1340,7 @@ namespace hw {
         hw::ledger::check32("generate_key_image", "image", image_x.data, image.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     /* ======================================================================= */
@@ -1393,12 +1348,9 @@ namespace hw {
     /* ======================================================================= */
 
     bool device_ledger::open_tx(crypto::secret_key &tx_key) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
-        lock_tx();
         reset_buffer();
         key_map.clear();
 
@@ -1423,57 +1375,19 @@ namespace hw {
         this->exchange();
 
         memmove(tx_key.data, &this->buffer_recv[32], 32);
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
-    }
-
-    bool  device_ledger::set_signature_mode(unsigned int sig_mode) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
-
-        reset_buffer();
-
-        this->buffer_send[0] = 0x00;
-        this->buffer_send[1] = INS_SET_SIGNATURE_MODE;
-        this->buffer_send[2] = 0x01;
-        this->buffer_send[3] = 0x00;
-        this->buffer_send[4] = 0x00;
-        offset = 5;
-        //options
-        this->buffer_send[offset] = 0x00;
-        offset += 1;
-        //account
-        this->buffer_send[offset] = sig_mode;
-        offset += 1;
-
-        this->buffer_send[4] = offset-5;
-        this->length_send = offset;
-        this->exchange();
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+  
+        return true;
     }
 
     bool device_ledger::encrypt_payment_id(crypto::hash8 &payment_id, const crypto::public_key &public_key, const crypto::secret_key &secret_key) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const crypto::public_key public_key_x = public_key;
         const crypto::secret_key secret_key_x = hw::ledger::decrypt(secret_key);
         crypto::hash8 payment_id_x = payment_id;
-        this->controle_device->encrypt_payment_id(public_key_x, secret_key_x, payment_id_x);
+        this->controle_device->encrypt_payment_id(payment_id_x, public_key_x, secret_key_x);
         #endif
 
         reset_buffer();
@@ -1506,32 +1420,19 @@ namespace hw {
         hw::ledger::check8("stealth", "payment_id", payment_id_x.data, payment_id.data);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::add_output_key_mapping(const crypto::public_key &Aout, const crypto::public_key &Bout, const bool is_subaddress, const size_t real_output_index,
                                                const rct::key &amount_key,  const crypto::public_key &out_eph_public_key)  {
-      lock_device();
-      try {
+        AUTO_LOCK_CMD();
         key_map.add(ABPkeys(rct::pk2rct(Aout),rct::pk2rct(Bout), is_subaddress, real_output_index, rct::pk2rct(out_eph_public_key), amount_key));
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool  device_ledger::ecdhEncode(rct::ecdhTuple & unmasked, const rct::key & AKout) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const rct::key AKout_x =   hw::ledger::decrypt(AKout);
@@ -1574,19 +1475,12 @@ namespace hw {
         hw::ledger::log_hexbuffer("Blind AKV input", (char*)&this->buffer_recv[64], 3*32);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool  device_ledger::ecdhDecode(rct::ecdhTuple & masked, const rct::key & AKout) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         #ifdef DEBUG_HWDEVICE
         const rct::key AKout_x =   hw::ledger::decrypt(AKout);
@@ -1627,21 +1521,13 @@ namespace hw {
         hw::ledger::check32("ecdhDecode", "mask", (char*)masked_x.mask.bytes,(char*) masked.mask.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::mlsag_prehash(const std::string &blob, size_t inputs_size, size_t outputs_size,
                                      const rct::keyV &hashes, const rct::ctkeyV &outPk,
                                      rct::key &prehash) {
-
-      lock_device();
-      try {
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
         unsigned int  data_offset, C_offset, kv_offset, i;
         const char *data;
 
@@ -1834,21 +1720,15 @@ namespace hw {
         hw::ledger::check32("mlsag_prehash", "prehash", (char*)prehash_x.bytes, (char*)prehash.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
 
     bool device_ledger::mlsag_prepare(const rct::key &H, const rct::key &xx,
                                      rct::key &a, rct::key &aG, rct::key &aHP, rct::key &II) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
+        unsigned char options;
 
         #ifdef DEBUG_HWDEVICE
         const rct::key H_x = H;
@@ -1897,19 +1777,13 @@ namespace hw {
         hw::ledger::check32("mlsag_prepare", "II", (char*)II_x.bytes, (char*)II.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::mlsag_prepare(rct::key &a, rct::key &aG) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
+        unsigned char options;
 
         #ifdef DEBUG_HWDEVICE
         rct::key a_x;
@@ -1941,19 +1815,13 @@ namespace hw {
         hw::ledger::check32("mlsag_prepare", "AG", (char*)aG_x.bytes, (char*)aG.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::mlsag_hash(const rct::keyV &long_message, rct::key &c) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
+        unsigned char options;
         size_t cnt;
 
         #ifdef DEBUG_HWDEVICE
@@ -1991,20 +1859,12 @@ namespace hw {
         hw::ledger::check32("mlsag_hash", "c", (char*)c_x.bytes, (char*)c.bytes);
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
-
+        return true;
     }
 
     bool device_ledger::mlsag_sign(const rct::key &c, const rct::keyV &xx, const rct::keyV &alpha, const size_t rows, const size_t dsRows, rct::keyV &ss) {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         CHECK_AND_ASSERT_THROW_MES(dsRows<=rows, "dsRows greater than rows");
         CHECK_AND_ASSERT_THROW_MES(xx.size() == rows, "xx size does not match rows");
@@ -2061,19 +1921,12 @@ namespace hw {
         }
         #endif
 
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     bool device_ledger::close_tx() {
-      lock_device();
-      try {
-        int offset =0;
-        unsigned char options = 0;
+        AUTO_LOCK_CMD();
+        int offset;
 
         reset_buffer();
 
@@ -2091,13 +1944,7 @@ namespace hw {
         this->length_send = offset;
         this->exchange();
 
-        unlock_tx();
-        unlock_device();
-      }catch (...)  {
-        unlock_device();
-        throw;
-      }
-      return true;
+        return true;
     }
 
     /* ---------------------------------------------------------- */
diff --git a/src/device/device_ledger.hpp b/src/device/device_ledger.hpp
index e06c5f72c..652cfb34b 100644
--- a/src/device/device_ledger.hpp
+++ b/src/device/device_ledger.hpp
@@ -32,11 +32,11 @@
 
 #include <cstddef>
 #include <string>
-#include <mutex>
 #include "device.hpp"
 #include <PCSC/winscard.h>
 #include <PCSC/wintypes.h>
-
+#include <boost/thread/mutex.hpp>
+#include <boost/thread/recursive_mutex.hpp>
 
 namespace hw {
 
@@ -80,13 +80,11 @@ namespace hw {
 
     class device_ledger : public hw::device {
     private:
-        mutable std::mutex   device_locker;
-        mutable std::mutex   tx_locker;
-        void lock_device() ;
-        void unlock_device() ;
-        void lock_tx() ;
-        void unlock_tx() ;
- 
+        // Locker for concurrent access
+        mutable boost::recursive_mutex   device_locker;
+        mutable boost::mutex   command_locker;
+
+        //PCSC management 
         std::string  full_name;
         SCARDCONTEXT hContext;
         SCARDHANDLE  hCard;
@@ -95,15 +93,21 @@ namespace hw {
         DWORD        length_recv;
         BYTE         buffer_recv[BUFFER_RECV_SIZE];
         unsigned int id;
-
-        Keymap key_map;
-
-
         void logCMD(void);
         void logRESP(void);
         unsigned int  exchange(unsigned int ok=0x9000, unsigned int mask=0xFFFF);
         void reset_buffer(void);
 
+        // hw running mode
+        device_mode mode;
+        // map public destination key to ephemeral destination key
+        Keymap key_map;
+
+        // To speed up blockchain parsing the view key maybe handle here.
+        crypto::secret_key viewkey;
+        bool has_view_key;
+        
+        //extra debug
         #ifdef DEBUG_HWDEVICE
         device *controle_device;
         #endif
@@ -130,6 +134,15 @@ namespace hw {
         bool connect(void) override;
         bool disconnect() override;
 
+        bool  set_mode(device_mode mode) override;
+
+        /* ======================================================================= */
+        /*  LOCKER                                                                 */
+        /* ======================================================================= */ 
+        void lock(void)  override;
+        void unlock(void) override;
+        bool try_lock(void) override;
+
         /* ======================================================================= */
         /*                             WALLET & ADDRESS                            */
         /* ======================================================================= */
@@ -168,8 +181,6 @@ namespace hw {
 
         bool  open_tx(crypto::secret_key &tx_key) override;
 
-        bool  set_signature_mode(unsigned int sig_mode) override;
-
         bool  encrypt_payment_id(crypto::hash8 &payment_id, const crypto::public_key &public_key, const crypto::secret_key &secret_key) override;
 
         bool  ecdhEncode(rct::ecdhTuple & unmasked, const rct::key & sharedSec) override;
@@ -190,10 +201,9 @@ namespace hw {
     };
 
 
-
     #ifdef DEBUG_HWDEVICE
-    extern crypto::secret_key viewkey;
-    extern crypto::secret_key spendkey;
+    extern crypto::secret_key dbg_viewkey;
+    extern crypto::secret_key dbg_spendkey;
     #endif
 
     #endif  //WITH_DEVICE_LEDGER
diff --git a/src/device/log.cpp b/src/device/log.cpp
index a2ad0f4f4..cbbcfc953 100644
--- a/src/device/log.cpp
+++ b/src/device/log.cpp
@@ -56,8 +56,8 @@ namespace hw {
     }
 
     #ifdef DEBUG_HWDEVICE
-    extern crypto::secret_key viewkey;
-    extern crypto::secret_key spendkey;
+    extern crypto::secret_key dbg_viewkey;
+    extern crypto::secret_key dbg_spendkey;
 
 
     void decrypt(char* buf, size_t len) {
@@ -69,7 +69,7 @@ namespace hw {
           if (buf[i] != 0) break;
         }
         if (i == 32) {
-          memmove(buf, hw::ledger::viewkey.data, 32);
+          memmove(buf, hw::ledger::dbg_viewkey.data, 32);
           return;
         }
         //spend key?
@@ -77,7 +77,7 @@ namespace hw {
           if (buf[i] != (char)0xff) break;
         }
         if (i == 32) {
-          memmove(buf, hw::ledger::spendkey.data, 32);
+          memmove(buf, hw::ledger::dbg_spendkey.data, 32);
           return;
         }
       }
@@ -161,4 +161,4 @@ namespace hw {
   }
   #endif //WITH_DEVICE_LEDGER    
 
-}
\ No newline at end of file
+}
diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
index 4e06c4692..b2651026f 100644
--- a/src/simplewallet/simplewallet.cpp
+++ b/src/simplewallet/simplewallet.cpp
@@ -2974,6 +2974,22 @@ bool simple_wallet::init(const boost::program_options::variables_map& vm)
       // create wallet
       bool r = new_wallet(vm, "Ledger");
       CHECK_AND_ASSERT_MES(r, false, tr("account creation failed"));
+      // if no block_height is specified, assume its a new account and start it "now"
+      if(m_wallet->get_refresh_from_block_height() == 0) {
+        {
+          tools::scoped_message_writer wrt = tools::msg_writer();
+          wrt << tr("No restore height is specified.");
+          wrt << tr("Assumed you are creating a new account, restore will be done from current estimated blockchain height.");
+          wrt << tr("Use --restore-height if you want to restore an already setup account from a specific height");
+        }
+        std::string confirm = input_line(tr("Is this okay?  (Y/Yes/N/No): "));
+        if (std::cin.eof() || !command_line::is_yes(confirm))
+          CHECK_AND_ASSERT_MES(false, false, tr("account creation aborted"));
+
+        m_wallet->set_refresh_from_block_height(m_wallet->estimate_blockchain_height()-1);
+        m_wallet->explicit_refresh_from_block_height(true);
+        m_restore_height = m_wallet->get_refresh_from_block_height();
+      }
     }
     else
     {
@@ -2990,7 +3006,7 @@ bool simple_wallet::init(const boost::program_options::variables_map& vm)
       CHECK_AND_ASSERT_MES(r, false, tr("account creation failed"));
     }
 
-    if (m_restoring && m_generate_from_json.empty())
+    if (m_restoring && m_generate_from_json.empty() && m_generate_from_device.empty())
     {
       m_wallet->explicit_refresh_from_block_height(!command_line::is_arg_defaulted(vm, arg_restore_height));
     }
@@ -3388,7 +3404,7 @@ bool simple_wallet::new_wallet(const boost::program_options::variables_map& vm,
   try
   {
     m_wallet->restore(m_wallet_file, std::move(rc.second).password(), device_name);
-    message_writer(console_color_white, true) << tr("Generated new on device wallet: ")
+    message_writer(console_color_white, true) << tr("Generated new wallet on hw device: ")
       << m_wallet->get_account().get_public_address_str(m_wallet->nettype());
   }
   catch (const std::exception& e)
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 7c9a66c26..27310f400 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -1007,13 +1007,16 @@ void wallet2::set_unspent(size_t idx)
 //----------------------------------------------------------------------------------------------------
 void wallet2::check_acc_out_precomp(const tx_out &o, const crypto::key_derivation &derivation, const std::vector<crypto::key_derivation> &additional_derivations, size_t i, tx_scan_info_t &tx_scan_info) const
 {
+  hw::device &hwdev = m_account.get_device();
+  std::unique_lock<hw::device> hwdev_lock (hwdev);
+  hwdev.set_mode(hw::device::TRANSACTION_PARSE);
   if (o.target.type() !=  typeid(txout_to_key))
   {
      tx_scan_info.error = true;
      LOG_ERROR("wrong type id in transaction out");
      return;
   }
-  tx_scan_info.received = is_out_to_acc_precomp(m_subaddresses, boost::get<txout_to_key>(o.target).key, derivation, additional_derivations, i, m_account.get_device());
+  tx_scan_info.received = is_out_to_acc_precomp(m_subaddresses, boost::get<txout_to_key>(o.target).key, derivation, additional_derivations, i, hwdev);
   if(tx_scan_info.received)
   {
     tx_scan_info.money_transfered = o.amount; // may be 0 for ringct outputs
@@ -1080,9 +1083,15 @@ void wallet2::scan_output(const cryptonote::transaction &tx, const crypto::publi
 //----------------------------------------------------------------------------------------------------
 void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote::transaction& tx, const std::vector<uint64_t> &o_indices, uint64_t height, uint64_t ts, bool miner_tx, bool pool, bool double_spend_seen)
 {
-  // In this function, tx (probably) only contains the base information
-  // (that is, the prunable stuff may or may not be included)
+  //ensure device is let in NONE mode in any case
+  hw::device &hwdev = m_account.get_device(); 
+  
+  std::unique_lock<hw::device> hwdev_lock (hwdev);
+  hw::reset_mode rst(hwdev);  
+  hwdev_lock.unlock();
 
+ // In this function, tx (probably) only contains the base information
+  // (that is, the prunable stuff may or may not be included)
   if (!miner_tx && !pool)
     process_unconfirmed(txid, tx, height);
   std::vector<size_t> outs;
@@ -1119,8 +1128,10 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
     tools::threadpool& tpool = tools::threadpool::getInstance();
     tools::threadpool::waiter waiter;
     const cryptonote::account_keys& keys = m_account.get_keys();
-    hw::device &hwdev = m_account.get_device();
     crypto::key_derivation derivation;
+
+    hwdev_lock.lock();
+    hwdev.set_mode(hw::device::TRANSACTION_PARSE);
     if (!hwdev.generate_key_derivation(tx_pub_key, keys.m_view_secret_key, derivation))
     {
       MWARNING("Failed to generate key derivation from tx pubkey, skipping");
@@ -1140,6 +1151,7 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
         additional_derivations.pop_back();
       }
     }
+    hwdev_lock.unlock();
 
     if (miner_tx && m_refresh_type == RefreshNoCoinbase)
     {
@@ -1161,16 +1173,19 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
             std::ref(tx_scan_info[i])));
         }
         waiter.wait();
-
         // then scan all outputs from 0
+        hwdev_lock.lock();
+        hwdev.set_mode(hw::device::NONE);
         for (size_t i = 0; i < tx.vout.size(); ++i)
         {
           THROW_WALLET_EXCEPTION_IF(tx_scan_info[i].error, error::acc_outs_lookup_error, tx, tx_pub_key, m_account.get_keys());
           if (tx_scan_info[i].received)
           {
+            hwdev.generate_key_derivation(tx_pub_key,  keys.m_view_secret_key, tx_scan_info[i].received->derivation);
             scan_output(tx, tx_pub_key, i, tx_scan_info[i], num_vouts_received, tx_money_got_in_outs, outs);
           }
         }
+        hwdev_lock.unlock();
       }
     }
     else if (tx.vout.size() > 1 && tools::threadpool::getInstance().get_max_concurrency() > 1)
@@ -1181,14 +1196,19 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
             std::ref(tx_scan_info[i])));
       }
       waiter.wait();
+
+      hwdev_lock.lock();
+      hwdev.set_mode(hw::device::NONE);
       for (size_t i = 0; i < tx.vout.size(); ++i)
       {
         THROW_WALLET_EXCEPTION_IF(tx_scan_info[i].error, error::acc_outs_lookup_error, tx, tx_pub_key, m_account.get_keys());
         if (tx_scan_info[i].received)
         {
+          hwdev.generate_key_derivation(tx_pub_key,  keys.m_view_secret_key, tx_scan_info[i].received->derivation);
           scan_output(tx, tx_pub_key, i, tx_scan_info[i], num_vouts_received, tx_money_got_in_outs, outs);
         }
       }
+      hwdev_lock.unlock();
     }
     else
     {
@@ -1198,7 +1218,11 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
         THROW_WALLET_EXCEPTION_IF(tx_scan_info[i].error, error::acc_outs_lookup_error, tx, tx_pub_key, m_account.get_keys());
         if (tx_scan_info[i].received)
         {
+          hwdev_lock.lock();
+          hwdev.set_mode(hw::device::NONE);
+          hwdev.generate_key_derivation(tx_pub_key,  keys.m_view_secret_key, tx_scan_info[i].received->derivation);
           scan_output(tx, tx_pub_key, i, tx_scan_info[i], num_vouts_received, tx_money_got_in_outs, outs);
+          hwdev_lock.unlock();
         }
       }
     }
@@ -7259,6 +7283,11 @@ bool wallet2::light_wallet_key_image_is_ours(const crypto::key_image& key_image,
 // usable balance.
 std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryptonote::tx_destination_entry> dsts, const size_t fake_outs_count, const uint64_t unlock_time, uint32_t priority, const std::vector<uint8_t>& extra, uint32_t subaddr_account, std::set<uint32_t> subaddr_indices, bool trusted_daemon)
 {
+  //ensure device is let in NONE mode in any case
+  hw::device &hwdev = m_account.get_device();
+  std::unique_lock<hw::device> hwdev_lock (hwdev);
+  hw::reset_mode rst(hwdev);  
+
   if(m_light_wallet) {
     // Populate m_transfers
     light_wallet_get_unspent_outs();
@@ -7476,8 +7505,8 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_2(std::vector<cryp
   unsigned int original_output_index = 0;
   std::vector<size_t>* unused_transfers_indices = &unused_transfers_indices_per_subaddr[0].second;
   std::vector<size_t>* unused_dust_indices      = &unused_dust_indices_per_subaddr[0].second;
-  hw::device &hwdev = m_account.get_device();
-  hwdev.set_signature_mode(hw::device::SIGNATURE_FAKE);
+  
+  hwdev.set_mode(hw::device::TRANSACTION_CREATE_FAKE);
   while ((!dsts.empty() && dsts[0].amount > 0) || adding_fee || !preferred_inputs.empty() || should_pick_a_second_output(use_rct, txes.back().selected_transfers.size(), *unused_transfers_indices, *unused_dust_indices)) {
     TX &tx = txes.back();
 
@@ -7706,7 +7735,7 @@ skip_tx:
   LOG_PRINT_L1("Done creating " << txes.size() << " transactions, " << print_money(accumulated_fee) <<
     " total fee, " << print_money(accumulated_change) << " total change");
 
-  hwdev.set_signature_mode(hw::device::SIGNATURE_REAL);
+  hwdev.set_mode(hw::device::TRANSACTION_CREATE_REAL);
   for (std::vector<TX>::iterator i = txes.begin(); i != txes.end(); ++i)
   {
     TX &tx = *i;
@@ -7837,6 +7866,11 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_single(const crypt
 
 std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const cryptonote::account_public_address &address, bool is_subaddress, std::vector<size_t> unused_transfers_indices, std::vector<size_t> unused_dust_indices, const size_t fake_outs_count, const uint64_t unlock_time, uint32_t priority, const std::vector<uint8_t>& extra, bool trusted_daemon)
 {
+  //ensure device is let in NONE mode in any case
+  hw::device &hwdev = m_account.get_device();
+  std::unique_lock<hw::device> hwdev_lock (hwdev);
+  hw::reset_mode rst(hwdev);  
+
   uint64_t accumulated_fee, accumulated_outputs, accumulated_change;
   struct TX {
     std::vector<size_t> selected_transfers;
@@ -7869,8 +7903,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const crypton
   needed_fee = 0;
 
   // while we have something to send
-  hw::device &hwdev = m_account.get_device();
-  hwdev.set_signature_mode(hw::device::SIGNATURE_FAKE);
+  hwdev.set_mode(hw::device::TRANSACTION_CREATE_FAKE);
   while (!unused_dust_indices.empty() || !unused_transfers_indices.empty()) {
     TX &tx = txes.back();
 
@@ -7956,7 +7989,7 @@ std::vector<wallet2::pending_tx> wallet2::create_transactions_from(const crypton
   LOG_PRINT_L1("Done creating " << txes.size() << " transactions, " << print_money(accumulated_fee) <<
     " total fee, " << print_money(accumulated_change) << " total change");
  
-  hwdev.set_signature_mode(hw::device::SIGNATURE_REAL);
+  hwdev.set_mode(hw::device::TRANSACTION_CREATE_REAL);
   for (std::vector<TX>::iterator i = txes.begin(); i != txes.end(); ++i)
   {
     TX &tx = *i;