wallet: new import_outputs/export_outputs commands

The intended use is to export outputs from a hot wallet, which
can scan incoming transfers from the network, and import them
in the cold wallet, which can't. The cold wallet can then compute
key images for those outputs, which can then be exported with
export_key_images, etc.

2 files changed, 102 insertions, 0 deletions

diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
index 09c574528..cef1d6dcf 100644
--- a/src/simplewallet/simplewallet.cpp
+++ b/src/simplewallet/simplewallet.cpp
@@ -78,6 +78,7 @@ typedef cryptonote::simple_wallet sw;
 #define DEFAULT_MIX 4
 
 #define KEY_IMAGE_EXPORT_FILE_MAGIC "Monero key image export\001"
+#define OUTPUT_EXPORT_FILE_MAGIC "Monero output export\001"
 
 // workaround for a suspected bug in pthread/kernel on MacOS X
 #ifdef __APPLE__
@@ -703,6 +704,8 @@ simple_wallet::simple_wallet()
   m_cmd_binder.set_handler("verify", boost::bind(&simple_wallet::verify, this, _1), tr("Verify a signature on the contents of a file"));
   m_cmd_binder.set_handler("export_key_images", boost::bind(&simple_wallet::export_key_images, this, _1), tr("Export a signed set of key images"));
   m_cmd_binder.set_handler("import_key_images", boost::bind(&simple_wallet::import_key_images, this, _1), tr("Import signed key images list and verify their spent status"));
+  m_cmd_binder.set_handler("export_outputs", boost::bind(&simple_wallet::export_outputs, this, _1), tr("Export a set of outputs owned by this wallet"));
+  m_cmd_binder.set_handler("import_outputs", boost::bind(&simple_wallet::import_outputs, this, _1), tr("Import set of outputs owned by this wallet"));
   m_cmd_binder.set_handler("help", boost::bind(&simple_wallet::help, this, _1), tr("Show this help"));
 }
 //----------------------------------------------------------------------------------------------------
@@ -4101,6 +4104,103 @@ bool simple_wallet::import_key_images(const std::vector<std::string> &args)
   return true;
 }
 //----------------------------------------------------------------------------------------------------
+bool simple_wallet::export_outputs(const std::vector<std::string> &args)
+{
+  if (args.size() != 1)
+  {
+    fail_msg_writer() << tr("usage: export_outputs <filename>");
+    return true;
+  }
+  std::string filename = args[0];
+
+  try
+  {
+    std::vector<tools::wallet2::transfer_details> outs = m_wallet->export_outputs();
+
+    std::stringstream oss;
+    boost::archive::binary_oarchive ar(oss);
+    ar << outs;
+
+    std::string data(OUTPUT_EXPORT_FILE_MAGIC, strlen(OUTPUT_EXPORT_FILE_MAGIC));
+    const cryptonote::account_public_address &keys = m_wallet->get_account().get_keys().m_account_address;
+    data += std::string((const char *)&keys.m_spend_public_key, sizeof(crypto::public_key));
+    data += std::string((const char *)&keys.m_view_public_key, sizeof(crypto::public_key));
+    bool r = epee::file_io_utils::save_string_to_file(filename, data + oss.str());
+    if (!r)
+    {
+      fail_msg_writer() << tr("failed to save file ") << filename;
+      return true;
+    }
+  }
+  catch (const std::exception &e)
+  {
+    LOG_ERROR("Error exporting outputs: " << e.what());
+    fail_msg_writer() << "Error exporting outputs: " << e.what();
+    return true;
+  }
+
+  success_msg_writer() << tr("Outputs exported to ") << filename;
+  return true;
+}
+//----------------------------------------------------------------------------------------------------
+bool simple_wallet::import_outputs(const std::vector<std::string> &args)
+{
+  if (args.size() != 1)
+  {
+    fail_msg_writer() << tr("usage: import_outputs <filename>");
+    return true;
+  }
+  std::string filename = args[0];
+
+  std::string data;
+  bool r = epee::file_io_utils::load_file_to_string(filename, data);
+  if (!r)
+  {
+    fail_msg_writer() << tr("failed to read file ") << filename;
+    return true;
+  }
+  const size_t magiclen = strlen(OUTPUT_EXPORT_FILE_MAGIC);
+  if (data.size() < magiclen || memcmp(data.data(), OUTPUT_EXPORT_FILE_MAGIC, magiclen))
+  {
+    fail_msg_writer() << "Bad output export file magic in " << filename;
+    return true;
+  }
+  const size_t headerlen = magiclen + 2 * sizeof(crypto::public_key);
+  if (data.size() < headerlen)
+  {
+    fail_msg_writer() << "Bad data size from file " << filename;
+    return true;
+  }
+  const crypto::public_key &public_spend_key = *(const crypto::public_key*)&data[magiclen];
+  const crypto::public_key &public_view_key = *(const crypto::public_key*)&data[magiclen + sizeof(crypto::public_key)];
+  const cryptonote::account_public_address &keys = m_wallet->get_account().get_keys().m_account_address;
+  if (public_spend_key != keys.m_spend_public_key || public_view_key != keys.m_view_public_key)
+  {
+    fail_msg_writer() << "Outputs from " << filename << " are for a different account";
+    return true;
+  }
+
+  try
+  {
+    std::string body(data, headerlen);
+    std::stringstream iss;
+    iss << body;
+    boost::archive::binary_iarchive ar(iss);
+    std::vector<tools::wallet2::transfer_details> outputs;
+    ar >> outputs;
+
+    size_t n_outputs = m_wallet->import_outputs(outputs);
+    success_msg_writer() << boost::lexical_cast<std::string>(n_outputs) << " outputs imported";
+  }
+  catch (const std::exception &e)
+  {
+    fail_msg_writer() << "Failed to import outputs: " << e.what();
+    return true;
+  }
+
+  return true;
+}
+//----------------------------------------------------------------------------------------------------
 bool simple_wallet::process_command(const std::vector<std::string> &args)
 {
   return m_cmd_binder.process_command_vec(args);
diff --git a/src/simplewallet/simplewallet.h b/src/simplewallet/simplewallet.h
index 375716604..92cc0ddfc 100644
--- a/src/simplewallet/simplewallet.h
+++ b/src/simplewallet/simplewallet.h
@@ -152,6 +152,8 @@ namespace cryptonote
     bool verify(const std::vector<std::string> &args);
     bool export_key_images(const std::vector<std::string> &args);
     bool import_key_images(const std::vector<std::string> &args);
+    bool export_outputs(const std::vector<std::string> &args);
+    bool import_outputs(const std::vector<std::string> &args);
 
     uint64_t get_daemon_blockchain_height(std::string& err);
     bool try_connect_to_daemon(bool silent = false);