device/trezor: passphrase entry on host

- simple device callback object added. Device can request passphrase/PIN entry via the callback or notify user some action is required
- callback is routed to wallet2, which routes the callback to i_wallet_callback so CLI or GUI wallets can support passphrase entry for HW tokens
- wallet: device open needs wallet callback first - passphrase protected device needs wallet callback so user can enter passphrase

3 files changed, 79 insertions, 3 deletions

diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 49aef4350..ae6ed0937 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -818,6 +818,24 @@ wallet_keys_unlocker::~wallet_keys_unlocker()
   w.encrypt_keys(key);
 }
 
+void wallet_device_callback::on_button_request()
+{
+  if (wallet)
+    wallet->on_button_request();
+}
+
+void wallet_device_callback::on_pin_request(epee::wipeable_string & pin)
+{
+  if (wallet)
+    wallet->on_pin_request(pin);
+}
+
+void wallet_device_callback::on_passphrase_request(bool on_device, epee::wipeable_string & passphrase)
+{
+  if (wallet)
+    wallet->on_passphrase_request(on_device, passphrase);
+}
+
 wallet2::wallet2(network_type nettype, uint64_t kdf_rounds, bool unattended):
   m_multisig_rescan_info(NULL),
   m_multisig_rescan_k(NULL),
@@ -929,7 +947,7 @@ std::pair<std::unique_ptr<wallet2>, password_container> wallet2::make_from_file(
     return {nullptr, password_container{}};
   }
   auto wallet = make_basic(vm, unattended, opts, password_prompter);
-  if (wallet)
+  if (wallet && !wallet_file.empty())
   {
     wallet->load(wallet_file, pwd->password());
   }
@@ -1071,15 +1089,16 @@ bool wallet2::reconnect_device()
   hw::device &hwdev = lookup_device(m_device_name);
   hwdev.set_name(m_device_name);
   hwdev.set_network_type(m_nettype);
+  hwdev.set_callback(get_device_callback());
   r = hwdev.init();
   if (!r){
-    LOG_PRINT_L2("Could not init device");
+    MERROR("Could not init device");
     return false;
   }
 
   r = hwdev.connect();
   if (!r){
-    LOG_PRINT_L2("Could not connect to the device");
+    MERROR("Could not connect to the device");
     return false;
   }
 
@@ -3441,6 +3460,7 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
     hw::device &hwdev = lookup_device(m_device_name);
     THROW_WALLET_EXCEPTION_IF(!hwdev.set_name(m_device_name), error::wallet_internal_error, "Could not set device name " + m_device_name);
     hwdev.set_network_type(m_nettype);
+    hwdev.set_callback(get_device_callback());
     THROW_WALLET_EXCEPTION_IF(!hwdev.init(), error::wallet_internal_error, "Could not initialize the device " + m_device_name);
     THROW_WALLET_EXCEPTION_IF(!hwdev.connect(), error::wallet_internal_error, "Could not connect to the device " + m_device_name);
     m_account.set_device(hwdev);
@@ -3947,6 +3967,7 @@ void wallet2::restore(const std::string& wallet_, const epee::wipeable_string& p
   auto &hwdev = lookup_device(device_name);
   hwdev.set_name(device_name);
   hwdev.set_network_type(m_nettype);
+  hwdev.set_callback(get_device_callback());
 
   m_account.create_from_device(hwdev);
   m_key_device_type = m_account.get_device().get_type();
@@ -11940,4 +11961,29 @@ uint64_t wallet2::get_segregation_fork_height() const
 void wallet2::generate_genesis(cryptonote::block& b) const {
   cryptonote::generate_genesis_block(b, get_config(m_nettype).GENESIS_TX, get_config(m_nettype).GENESIS_NONCE);
 }
+//----------------------------------------------------------------------------------------------------
+wallet_device_callback * wallet2::get_device_callback()
+{
+  if (!m_device_callback){
+    m_device_callback.reset(new wallet_device_callback(this));
+  }
+  return m_device_callback.get();
+}//----------------------------------------------------------------------------------------------------
+void wallet2::on_button_request()
+{
+  if (0 != m_callback)
+    m_callback->on_button_request();
+}
+//----------------------------------------------------------------------------------------------------
+void wallet2::on_pin_request(epee::wipeable_string & pin)
+{
+  if (0 != m_callback)
+    m_callback->on_pin_request(pin);
+}
+//----------------------------------------------------------------------------------------------------
+void wallet2::on_passphrase_request(bool on_device, epee::wipeable_string & passphrase)
+{
+  if (0 != m_callback)
+    m_callback->on_passphrase_request(on_device, passphrase);
+}
 }
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index eb0763131..c07054177 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -98,11 +98,26 @@ namespace tools
     virtual void on_lw_money_received(uint64_t height, const crypto::hash &txid, uint64_t amount) {}
     virtual void on_lw_unconfirmed_money_received(uint64_t height, const crypto::hash &txid, uint64_t amount) {}
     virtual void on_lw_money_spent(uint64_t height, const crypto::hash &txid, uint64_t amount) {}
+    // Device callbacks
+    virtual void on_button_request() {}
+    virtual void on_pin_request(epee::wipeable_string & pin) {}
+    virtual void on_passphrase_request(bool on_device, epee::wipeable_string & passphrase) {}
     // Common callbacks
     virtual void on_pool_tx_removed(const crypto::hash &txid) {}
     virtual ~i_wallet2_callback() {}
   };
 
+  class wallet_device_callback : public hw::i_device_callback
+  {
+  public:
+    wallet_device_callback(wallet2 * wallet): wallet(wallet) {};
+    void on_button_request() override;
+    void on_pin_request(epee::wipeable_string & pin) override;
+    void on_passphrase_request(bool on_device, epee::wipeable_string & passphrase) override;
+  private:
+    wallet2 * wallet;
+  };
+
   struct tx_dust_policy
   {
     uint64_t dust_threshold;
@@ -154,6 +169,7 @@ namespace tools
   {
     friend class ::Serialization_portability_wallet_Test;
     friend class wallet_keys_unlocker;
+    friend class wallet_device_callback;
   public:
     static constexpr const std::chrono::seconds rpc_timeout = std::chrono::minutes(3) + std::chrono::seconds(30);
 
@@ -1285,6 +1301,11 @@ namespace tools
     void setup_new_blockchain();
     void create_keys_file(const std::string &wallet_, bool watch_only, const epee::wipeable_string &password, bool create_address_file);
 
+    wallet_device_callback * get_device_callback();
+    void on_button_request();
+    void on_pin_request(epee::wipeable_string & pin);
+    void on_passphrase_request(bool on_device, epee::wipeable_string & passphrase);
+
     cryptonote::account_base m_account;
     boost::optional<epee::net_utils::http::login> m_daemon_login;
     std::string m_daemon_address;
@@ -1396,6 +1417,7 @@ namespace tools
     bool m_devices_registered;
 
     std::shared_ptr<tools::Notify> m_tx_notify;
+    std::unique_ptr<wallet_device_callback> m_device_callback;
   };
 }
 BOOST_CLASS_VERSION(tools::wallet2, 26)
diff --git a/src/wallet/wallet_errors.h b/src/wallet/wallet_errors.h
index b3141985d..e2caee5d2 100644
--- a/src/wallet/wallet_errors.h
+++ b/src/wallet/wallet_errors.h
@@ -219,6 +219,14 @@ namespace tools
       }
     };
     //----------------------------------------------------------------------------------------------------
+    struct password_entry_failed : public wallet_runtime_error
+    {
+      explicit password_entry_failed(std::string&& loc, const std::string &msg = "Password entry failed")
+        : wallet_runtime_error(std::move(loc), msg)
+      {
+      }
+    };
+    //----------------------------------------------------------------------------------------------------
     const char* const file_error_messages[] = {
       "file already exists",
       "file not found",