hw_device: support for multiple devices added [for review]

- device name is a new wallet property
- full device name is now a bit more structured so we can address particular device vendor + device path. Example: 'Ledger', 'Trezor:udp', 'Trezor:udp:127.0.0.1:21324', 'Trezor:bridge:usb01'. The part before ':' identifies HW device implementation, the optional part after ':' is device path to look for.
- new --hw-device parameter added to the wallet, can name the hardware device
- device reconnect added

2 files changed, 54 insertions, 2 deletions

diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index b266821d6..dc7ab668f 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -161,6 +161,7 @@ struct options {
     }
   };
   const command_line::arg_descriptor<uint64_t> kdf_rounds = {"kdf-rounds", tools::wallet2::tr("Number of rounds for the key derivation function"), 1};
+  const command_line::arg_descriptor<std::string> hw_device = {"hw-device", tools::wallet2::tr("HW device to use"), ""};
 };
 
 void do_prepare_file_names(const std::string& file_path, std::string& keys_file, std::string& wallet_file)
@@ -211,6 +212,7 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   auto daemon_address = command_line::get_arg(vm, opts.daemon_address);
   auto daemon_host = command_line::get_arg(vm, opts.daemon_host);
   auto daemon_port = command_line::get_arg(vm, opts.daemon_port);
+  auto device_name = command_line::get_arg(vm, opts.hw_device);
 
   THROW_WALLET_EXCEPTION_IF(!daemon_address.empty() && !daemon_host.empty() && 0 != daemon_port,
       tools::error::wallet_internal_error, tools::wallet2::tr("can't specify daemon host or port more than once"));
@@ -265,6 +267,7 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   wallet->init(unattended, std::move(daemon_address), std::move(login), 0, false, *trusted_daemon);
   boost::filesystem::path ringdb_path = command_line::get_arg(vm, opts.shared_ringdb_dir);
   wallet->set_ring_database(ringdb_path.string());
+  wallet->device_name(device_name);
   return wallet;
 }
 
@@ -814,6 +817,11 @@ bool wallet2::has_stagenet_option(const boost::program_options::variables_map& v
   return command_line::get_arg(vm, options().stagenet);
 }
 
+std::string wallet2::device_name_option(const boost::program_options::variables_map& vm)
+{
+  return command_line::get_arg(vm, options().hw_device);
+}
+
 void wallet2::init_options(boost::program_options::options_description& desc_params)
 {
   const options opts{};
@@ -829,6 +837,7 @@ void wallet2::init_options(boost::program_options::options_description& desc_par
   command_line::add_arg(desc_params, opts.stagenet);
   command_line::add_arg(desc_params, opts.shared_ringdb_dir);
   command_line::add_arg(desc_params, opts.kdf_rounds);
+  command_line::add_arg(desc_params, opts.hw_device);
 }
 
 std::unique_ptr<wallet2> wallet2::make_from_json(const boost::program_options::variables_map& vm, bool unattended, const std::string& json_file, const std::function<boost::optional<tools::password_container>(const char *, bool)> &password_prompter)
@@ -984,6 +993,27 @@ bool wallet2::get_multisig_seed(epee::wipeable_string& seed, const epee::wipeabl
   return true;
 }
 //----------------------------------------------------------------------------------------------------
+bool wallet2::reconnect_device()
+{
+  bool r = true;
+  hw::device &hwdev = hw::get_device(m_device_name);
+  hwdev.set_name(m_device_name);
+  r = hwdev.init();
+  if (!r){
+    LOG_PRINT_L2("Could not init device");
+    return false;
+  }
+
+  r = hwdev.connect();
+  if (!r){
+    LOG_PRINT_L2("Could not connect to the device");
+    return false;
+  }
+
+  m_account.set_device(hwdev);
+  return true;
+}
+//----------------------------------------------------------------------------------------------------
 /*!
  * \brief Gets the seed language
  */
@@ -2980,6 +3010,9 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
   value2.SetUint(1);
   json.AddMember("encrypted_secret_keys", value2, json.GetAllocator());
 
+  value.SetString(m_device_name.c_str(), m_device_name.size());
+  json.AddMember("device_name", value, json.GetAllocator());
+
   // Serialize the JSON object
   rapidjson::StringBuffer buffer;
   rapidjson::Writer<rapidjson::StringBuffer> writer(buffer);
@@ -3088,6 +3121,7 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
     m_ignore_fractional_outputs = true;
     m_subaddress_lookahead_major = SUBADDRESS_LOOKAHEAD_MAJOR;
     m_subaddress_lookahead_minor = SUBADDRESS_LOOKAHEAD_MINOR;
+    m_device_name = "";
     m_key_on_device = false;
     encrypted_secret_keys = false;
   }
@@ -3219,8 +3253,15 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
     m_subaddress_lookahead_major = field_subaddress_lookahead_major;
     GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, subaddress_lookahead_minor, uint32_t, Uint, false, SUBADDRESS_LOOKAHEAD_MINOR);
     m_subaddress_lookahead_minor = field_subaddress_lookahead_minor;
+
     GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, encrypted_secret_keys, uint32_t, Uint, false, false);
     encrypted_secret_keys = field_encrypted_secret_keys;
+
+    GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, device_name, std::string, String, false, std::string());
+    if (m_device_name.empty() && field_device_name_found)
+    {
+      m_device_name = field_device_name;
+    }
   }
   else
   {
@@ -3231,7 +3272,8 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
   r = epee::serialization::load_t_from_binary(m_account, account_data);
   if (r && m_key_on_device) {
     LOG_PRINT_L0("Account on device. Initing device...");
-    hw::device &hwdev = hw::get_device("Ledger");
+    hw::device &hwdev = hw::get_device(m_device_name);
+    hwdev.set_name(m_device_name);
     hwdev.init();
     hwdev.connect();
     m_account.set_device(hwdev);
@@ -3673,13 +3715,18 @@ void wallet2::restore(const std::string& wallet_, const epee::wipeable_string& p
     THROW_WALLET_EXCEPTION_IF(boost::filesystem::exists(m_keys_file,   ignored_ec), error::file_exists, m_keys_file);
   }
   m_key_on_device = true;
-  m_account.create_from_device(device_name);
+
+  auto &hwdev = hw::get_device(device_name);
+  hwdev.set_name(device_name);
+
+  m_account.create_from_device(hwdev);
   m_account_public_address = m_account.get_keys().m_account_address;
   m_watch_only = false;
   m_multisig = false;
   m_multisig_threshold = 0;
   m_multisig_signers.clear();
   setup_keys(password);
+  m_device_name = device_name;
 
   create_keys_file(wallet_, false, password, m_nettype != MAINNET || create_address_file);
   if (m_subaddress_lookahead_major == SUBADDRESS_LOOKAHEAD_MAJOR && m_subaddress_lookahead_minor == SUBADDRESS_LOOKAHEAD_MINOR)
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index 402066b50..2f833c679 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -172,6 +172,7 @@ namespace tools
 
     static bool has_testnet_option(const boost::program_options::variables_map& vm);
     static bool has_stagenet_option(const boost::program_options::variables_map& vm);
+    static std::string device_name_option(const boost::program_options::variables_map& vm);
     static void init_options(boost::program_options::options_description& desc_params);
 
     //! Uses stdin and stdout. Returns a wallet2 if no errors.
@@ -709,6 +710,7 @@ namespace tools
     bool has_unknown_key_images() const;
     bool get_multisig_seed(epee::wipeable_string& seed, const epee::wipeable_string &passphrase = std::string(), bool raw = true) const;
     bool key_on_device() const { return m_key_on_device; }
+    bool reconnect_device();
 
     // locked & unlocked balance of given or current subaddress account
     uint64_t balance(uint32_t subaddr_index_major) const;
@@ -938,6 +940,8 @@ namespace tools
     void ignore_fractional_outputs(bool value) { m_ignore_fractional_outputs = value; }
     bool confirm_non_default_ring_size() const { return m_confirm_non_default_ring_size; }
     void confirm_non_default_ring_size(bool always) { m_confirm_non_default_ring_size = always; }
+    const std::string & device_name() const { return m_device_name; }
+    void device_name(const std::string & device_name) { m_device_name = device_name; }
 
     bool get_tx_key(const crypto::hash &txid, crypto::secret_key &tx_key, std::vector<crypto::secret_key> &additional_tx_keys) const;
     void set_tx_key(const crypto::hash &txid, const crypto::secret_key &tx_key, const std::vector<crypto::secret_key> &additional_tx_keys);
@@ -1319,6 +1323,7 @@ namespace tools
     NodeRPCProxy m_node_rpc_proxy;
     std::unordered_set<crypto::hash> m_scanned_pool_txs[2];
     size_t m_subaddress_lookahead_major, m_subaddress_lookahead_minor;
+    std::string m_device_name;
 
     // Light wallet
     bool m_light_wallet; /* sends view key to daemon for scanning */