Code modifications to integrate Ledger HW device into monero-wallet-cli.

The basic approach it to delegate all sensitive data (master key, secret
ephemeral key, key derivation, ....) and related operations to the device.
As device has low memory, it does not keep itself the values
(except for view/spend keys) but once computed there are encrypted (with AES
are equivalent) and return back to monero-wallet-cli. When they need to be
manipulated by the device, they are decrypted on receive.

Moreover, using the client for storing the value in encrypted form limits
the modification in the client code. Those values are transfered from one
C-structure to another one as previously.

The code modification has been done with the wishes to be open to any
other hardware wallet. To achieve that a C++ class hw::Device has been
introduced. Two initial implementations are provided: the "default", which
remaps all calls to initial Monero code, and  the "Ledger", which delegates
all calls to Ledger device.

2 files changed, 163 insertions, 5 deletions

diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
index c67a6bc6c..02deee0c7 100644
--- a/src/simplewallet/simplewallet.cpp
+++ b/src/simplewallet/simplewallet.cpp
@@ -62,6 +62,7 @@
 #include "ringct/rctSigs.h"
 #include "multisig/multisig.h"
 #include "wallet/wallet_args.h"
+#include "device/device.hpp"
 #include <stdexcept>
 
 #ifdef HAVE_READLINE
@@ -113,6 +114,7 @@ namespace
   const std::array<const char* const, 5> allowed_priority_strings = {{"default", "unimportant", "normal", "elevated", "priority"}};
   const auto arg_wallet_file = wallet_args::arg_wallet_file();
   const command_line::arg_descriptor<std::string> arg_generate_new_wallet = {"generate-new-wallet", sw::tr("Generate new wallet and save it to <arg>"), ""};
+  const command_line::arg_descriptor<std::string> arg_generate_from_device = {"generate-from-device", sw::tr("Generate new wallet from device and save it to <arg>"), ""};
   const command_line::arg_descriptor<std::string> arg_generate_from_view_key = {"generate-from-view-key", sw::tr("Generate incoming-only wallet from view key"), ""};
   const command_line::arg_descriptor<std::string> arg_generate_from_spend_key = {"generate-from-spend-key", sw::tr("Generate deterministic wallet from spend key"), ""};
   const command_line::arg_descriptor<std::string> arg_generate_from_keys = {"generate-from-keys", sw::tr("Generate wallet from private keys"), ""};
@@ -509,7 +511,11 @@ bool simple_wallet::viewkey(const std::vector<std::string> &args/* = std::vector
 {
   if (m_wallet->ask_password() && !get_and_verify_password()) { return true; }
   // don't log
-  std::cout << "secret: " << string_tools::pod_to_hex(m_wallet->get_account().get_keys().m_view_secret_key) << std::endl;
+  if (m_wallet->key_on_device()) {
+    std::cout << "secret: On device. Not available" << std::endl;
+  } else {
+    std::cout << "secret: " << string_tools::pod_to_hex(m_wallet->get_account().get_keys().m_view_secret_key) << std::endl;
+  }
   std::cout << "public: " << string_tools::pod_to_hex(m_wallet->get_account().get_keys().m_account_address.m_view_public_key) << std::endl;
 
   return true;
@@ -524,7 +530,11 @@ bool simple_wallet::spendkey(const std::vector<std::string> &args/* = std::vecto
   }
   if (m_wallet->ask_password() && !get_and_verify_password()) { return true; }
   // don't log
-  std::cout << "secret: " << string_tools::pod_to_hex(m_wallet->get_account().get_keys().m_spend_secret_key) << std::endl;
+  if (m_wallet->key_on_device()) {
+    std::cout << "secret: On device. Not available" << std::endl;
+  } else {
+    std::cout << "secret: " << string_tools::pod_to_hex(m_wallet->get_account().get_keys().m_spend_secret_key) << std::endl;
+  }
   std::cout << "public: " << string_tools::pod_to_hex(m_wallet->get_account().get_keys().m_account_address.m_spend_public_key) << std::endl;
 
   return true;
@@ -536,6 +546,11 @@ bool simple_wallet::print_seed(bool encrypted)
   std::string seed;
   bool ready, multisig;
 
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (m_wallet->watch_only())
   {
     fail_msg_writer() << tr("wallet is watch-only and has no seed");
@@ -598,6 +613,11 @@ bool simple_wallet::encrypted_seed(const std::vector<std::string> &args/* = std:
 
 bool simple_wallet::seed_set_language(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (m_wallet->multisig())
   {
     fail_msg_writer() << tr("wallet is multisig and has no seed");
@@ -726,6 +746,11 @@ bool simple_wallet::print_fee_info(const std::vector<std::string> &args/* = std:
 
 bool simple_wallet::prepare_multisig(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (m_wallet->multisig())
   {
     fail_msg_writer() << tr("This wallet is already multisig");
@@ -759,6 +784,11 @@ bool simple_wallet::prepare_multisig(const std::vector<std::string> &args)
 
 bool simple_wallet::make_multisig(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (m_wallet->multisig())
   {
     fail_msg_writer() << tr("This wallet is already multisig");
@@ -833,6 +863,11 @@ bool simple_wallet::make_multisig(const std::vector<std::string> &args)
 bool simple_wallet::finalize_multisig(const std::vector<std::string> &args)
 {
   bool ready;
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!m_wallet->multisig(&ready))
   {
     fail_msg_writer() << tr("This wallet is not multisig");
@@ -877,6 +912,11 @@ bool simple_wallet::finalize_multisig(const std::vector<std::string> &args)
 bool simple_wallet::export_multisig(const std::vector<std::string> &args)
 {
   bool ready;
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!m_wallet->multisig(&ready))
   {
     fail_msg_writer() << tr("This wallet is not multisig");
@@ -924,6 +964,11 @@ bool simple_wallet::import_multisig(const std::vector<std::string> &args)
 {
   bool ready;
   uint32_t threshold, total;
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!m_wallet->multisig(&ready, &threshold, &total))
   {
     fail_msg_writer() << tr("This wallet is not multisig");
@@ -998,6 +1043,11 @@ bool simple_wallet::accept_loaded_tx(const tools::wallet2::multisig_tx_set &txs)
 bool simple_wallet::sign_multisig(const std::vector<std::string> &args)
 {
   bool ready;
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if(!m_wallet->multisig(&ready))
   {
     fail_msg_writer() << tr("This is not a multisig wallet");
@@ -1066,6 +1116,11 @@ bool simple_wallet::submit_multisig(const std::vector<std::string> &args)
 {
   bool ready;
   uint32_t threshold;
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!m_wallet->multisig(&ready, &threshold))
   {
     fail_msg_writer() << tr("This is not a multisig wallet");
@@ -1128,6 +1183,11 @@ bool simple_wallet::export_raw_multisig(const std::vector<std::string> &args)
 {
   bool ready;
   uint32_t threshold;
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!m_wallet->multisig(&ready, &threshold))
   {
     fail_msg_writer() << tr("This is not a multisig wallet");
@@ -2065,12 +2125,12 @@ bool simple_wallet::init(const boost::program_options::variables_map& vm)
   if (!handle_command_line(vm))
     return false;
 
-  if((!m_generate_new.empty()) + (!m_wallet_file.empty()) + (!m_generate_from_view_key.empty()) + (!m_generate_from_spend_key.empty()) + (!m_generate_from_keys.empty()) + (!m_generate_from_multisig_keys.empty()) + (!m_generate_from_json.empty()) > 1)
+  if((!m_generate_new.empty()) + (!m_wallet_file.empty()) + (!m_generate_from_device.empty()) + (!m_generate_from_view_key.empty()) + (!m_generate_from_spend_key.empty()) + (!m_generate_from_keys.empty()) + (!m_generate_from_multisig_keys.empty()) + (!m_generate_from_json.empty()) > 1)
   {
-    fail_msg_writer() << tr("can't specify more than one of --generate-new-wallet=\"wallet_name\", --wallet-file=\"wallet_name\", --generate-from-view-key=\"wallet_name\", --generate-from-spend-key=\"wallet_name\", --generate-from-keys=\"wallet_name\", --generate-from-multisig-keys=\"wallet_name\" and --generate-from-json=\"jsonfilename\"");
+    fail_msg_writer() << tr("can't specify more than one of --generate-new-wallet=\"wallet_name\", --wallet-file=\"wallet_name\", --generate-from-view-key=\"wallet_name\", --generate-from-spend-key=\"wallet_name\", --generate-from-keys=\"wallet_name\", --generate-from-multisig-keys=\"wallet_name\", --generate-from-json=\"jsonfilename\" and --generate-from-device=\"wallet_name\"");
     return false;
   }
-  else if (m_generate_new.empty() && m_wallet_file.empty() && m_generate_from_view_key.empty() && m_generate_from_spend_key.empty() && m_generate_from_keys.empty() && m_generate_from_multisig_keys.empty() && m_generate_from_json.empty())
+  else if (m_generate_new.empty() && m_wallet_file.empty() && m_generate_from_device.empty() && m_generate_from_view_key.empty() && m_generate_from_spend_key.empty() && m_generate_from_keys.empty() && m_generate_from_multisig_keys.empty() && m_generate_from_json.empty())
   {
     if(!ask_wallet_create_if_needed()) return false;
   }
@@ -2467,6 +2527,13 @@ bool simple_wallet::init(const boost::program_options::variables_map& vm)
       if (!m_wallet)
         return false;
     }
+    else if (!m_generate_from_device.empty())
+    {
+      m_wallet_file = m_generate_from_device;
+      // create wallet
+      bool r = new_wallet(vm, "Ledger");
+      CHECK_AND_ASSERT_MES(r, false, tr("account creation failed"));
+    }
     else
     {
       if (m_generate_new.empty()) {
@@ -2601,6 +2668,7 @@ bool simple_wallet::handle_command_line(const boost::program_options::variables_
 {
   m_wallet_file                   = command_line::get_arg(vm, arg_wallet_file);
   m_generate_new                  = command_line::get_arg(vm, arg_generate_new_wallet);
+  m_generate_from_device          = command_line::get_arg(vm, arg_generate_from_device);
   m_generate_from_view_key        = command_line::get_arg(vm, arg_generate_from_view_key);
   m_generate_from_spend_key       = command_line::get_arg(vm, arg_generate_from_spend_key);
   m_generate_from_keys            = command_line::get_arg(vm, arg_generate_from_keys);
@@ -2620,6 +2688,7 @@ bool simple_wallet::handle_command_line(const boost::program_options::variables_
                                     !m_generate_from_keys.empty() ||
                                     !m_generate_from_multisig_keys.empty() ||
                                     !m_generate_from_json.empty() ||
+                                    !m_generate_from_device.empty() ||
                                     m_restore_deterministic_wallet ||
                                     m_restore_multisig_wallet;
 
@@ -2820,6 +2889,33 @@ bool simple_wallet::new_wallet(const boost::program_options::variables_map& vm,
 
   return true;
 }
+
+//----------------------------------------------------------------------------------------------------
+bool simple_wallet::new_wallet(const boost::program_options::variables_map& vm,
+                               const std::string &device_name) {
+  auto rc = tools::wallet2::make_new(vm, password_prompter);
+  m_wallet = std::move(rc.first);
+  if (!m_wallet)
+  {
+    return false;
+  }
+  if (m_restore_height)
+    m_wallet->set_refresh_from_block_height(m_restore_height);
+
+  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: ")
+      << m_wallet->get_account().get_public_address_str(m_wallet->testnet());
+  }
+  catch (const std::exception& e)
+  {
+    fail_msg_writer() << tr("failed to generate new wallet: ") << e.what();
+    return false;
+  }
+
+  return true;
+}
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::new_wallet(const boost::program_options::variables_map& vm,
     const std::string &multisig_keys, const std::string &old_language)
@@ -2893,6 +2989,9 @@ bool simple_wallet::open_wallet(const boost::program_options::variables_map& vm)
       prefix = tr("Opened wallet");
     message_writer(console_color_white, true) <<
       prefix << ": " << m_wallet->get_account().get_public_address_str(m_wallet->testnet());
+    if (m_wallet->get_account().get_device()) {
+       message_writer(console_color_white, true) << "Wallet is on device: " << m_wallet->get_account().get_device().get_name();
+    }
     // If the wallet file is deprecated, we should ask for mnemonic language again and store
     // everything in the new format.
     // NOTE: this is_deprecated() refers to the wallet file format before becoming JSON. It does not refer to the "old english" seed words form of "deprecated" used elsewhere.
@@ -3087,6 +3186,7 @@ bool simple_wallet::stop_mining(const std::vector<std::string>& args)
     fail_msg_writer() << tr("wallet is null");
     return true;
   }
+
   COMMAND_RPC_STOP_MINING::request req;
   COMMAND_RPC_STOP_MINING::response res;
   bool r = net_utils::invoke_http_json("/stop_mining", req, res, m_http_client);
@@ -4776,6 +4876,11 @@ bool simple_wallet::accept_loaded_tx(const tools::wallet2::signed_tx_set &txs)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::sign_transfer(const std::vector<std::string> &args_)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if(m_wallet->multisig())
   {
      fail_msg_writer() << tr("This is a multisig wallet, it can only sign with sign_multisig");
@@ -4834,6 +4939,11 @@ bool simple_wallet::sign_transfer(const std::vector<std::string> &args_)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::submit_transfer(const std::vector<std::string> &args_)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!try_connect_to_daemon())
     return true;
 
@@ -4866,6 +4976,11 @@ bool simple_wallet::get_tx_key(const std::vector<std::string> &args_)
 {
   std::vector<std::string> local_args = args_;
 
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if(local_args.size() != 1) {
     fail_msg_writer() << tr("usage: get_tx_key <txid>");
     return true;
@@ -4901,6 +5016,11 @@ bool simple_wallet::get_tx_key(const std::vector<std::string> &args_)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::get_tx_proof(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (args.size() != 2 && args.size() != 3)
   {
     fail_msg_writer() << tr("usage: get_tx_proof <txid> <address> [<message>]");
@@ -5107,6 +5227,11 @@ bool simple_wallet::check_tx_proof(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::get_spend_proof(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if(args.size() != 1 && args.size() != 2) {
     fail_msg_writer() << tr("usage: get_spend_proof <txid> [<message>]");
     return true;
@@ -5192,6 +5317,11 @@ bool simple_wallet::check_spend_proof(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::get_reserve_proof(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if(args.size() != 1 && args.size() != 2) {
     fail_msg_writer() << tr("usage: get_reserve_proof (all|<amount>) [<message>]");
     return true;
@@ -6293,6 +6423,11 @@ bool simple_wallet::wallet_info(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::sign(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (args.size() != 1)
   {
     fail_msg_writer() << tr("usage: sign <filename>");
@@ -6362,6 +6497,11 @@ bool simple_wallet::verify(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::export_key_images(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (args.size() != 1)
   {
     fail_msg_writer() << tr("usage: export_key_images <filename>");
@@ -6399,6 +6539,11 @@ bool simple_wallet::export_key_images(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::import_key_images(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (!m_trusted_daemon)
   {
     fail_msg_writer() << tr("this command requires a trusted daemon. Enable with --trusted-daemon");
@@ -6436,6 +6581,11 @@ bool simple_wallet::import_key_images(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::export_outputs(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (args.size() != 1)
   {
     fail_msg_writer() << tr("usage: export_outputs <filename>");
@@ -6481,6 +6631,11 @@ bool simple_wallet::export_outputs(const std::vector<std::string> &args)
 //----------------------------------------------------------------------------------------------------
 bool simple_wallet::import_outputs(const std::vector<std::string> &args)
 {
+  if (m_wallet->key_on_device())
+  {
+    fail_msg_writer() << tr("command not supported by HW wallet");
+    return true;
+  }
   if (args.size() != 1)
   {
     fail_msg_writer() << tr("usage: import_outputs <filename>");
@@ -6755,6 +6910,7 @@ int main(int argc, char* argv[])
   tools::wallet2::init_options(desc_params);
   command_line::add_arg(desc_params, arg_wallet_file);
   command_line::add_arg(desc_params, arg_generate_new_wallet);
+  command_line::add_arg(desc_params, arg_generate_from_device);
   command_line::add_arg(desc_params, arg_generate_from_view_key);
   command_line::add_arg(desc_params, arg_generate_from_spend_key);
   command_line::add_arg(desc_params, arg_generate_from_keys);
diff --git a/src/simplewallet/simplewallet.h b/src/simplewallet/simplewallet.h
index af2f940c3..4c7818bf1 100644
--- a/src/simplewallet/simplewallet.h
+++ b/src/simplewallet/simplewallet.h
@@ -97,6 +97,7 @@ namespace cryptonote
         const boost::optional<crypto::secret_key>& spendkey, const crypto::secret_key& viewkey);
     bool new_wallet(const boost::program_options::variables_map& vm,
         const std::string &multisig_keys, const std::string &old_language);
+    bool new_wallet(const boost::program_options::variables_map& vm, const std::string& device_name);
     bool open_wallet(const boost::program_options::variables_map& vm);
     bool close_wallet();
 
@@ -303,6 +304,7 @@ namespace cryptonote
   private:
     std::string m_wallet_file;
     std::string m_generate_new;
+    std::string m_generate_from_device;
     std::string m_generate_from_view_key;
     std::string m_generate_from_spend_key;
     std::string m_generate_from_keys;