simplewallet command to change seed language: "set seed language"

src/simplewallet/simplewallet.cpp

@@ -231,6 +231,36 @@ bool simple_wallet::seed(const std::vector<std::string> &args/* = std::vector<st
   return true;
 }
 
+bool simple_wallet::seed_set_language(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
+{
+  bool success = false;
+  if (!m_wallet->is_deterministic())
+  {
+    fail_msg_writer() << "This wallet is non-deterministic and doesn't have a seed.";
+    return true;
+  }
+  tools::password_container pwd_container;
+  success = pwd_container.read_password();
+  if (!success)
+  {
+    fail_msg_writer() << "failed to read wallet password";
+    return true;
+  }
+
+  /* verify password before using so user doesn't accidentally set a new password for rewritten wallet */
+  success = m_wallet->verify_password(pwd_container.password());
+  if (!success)
+  {
+    fail_msg_writer() << "invalid password";
+    return true;
+  }
+
+  std::string mnemonic_language = get_mnemonic_language();
+  m_wallet->set_seed_language(mnemonic_language);
+  m_wallet->rewrite(m_wallet_file, pwd_container.password());
+  return true;
+}
+
 bool simple_wallet::help(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
 {
   success_msg_writer() << get_commands_str();
@@ -255,9 +285,39 @@ simple_wallet::simple_wallet()
   m_cmd_binder.set_handler("save", boost::bind(&simple_wallet::save, this, _1), "Save wallet synchronized data");
   m_cmd_binder.set_handler("viewkey", boost::bind(&simple_wallet::viewkey, this, _1), "Get viewkey");
   m_cmd_binder.set_handler("seed", boost::bind(&simple_wallet::seed, this, _1), "Get deterministic seed");
+  m_cmd_binder.set_handler("set", boost::bind(&simple_wallet::set_variable, this, _1), "available options: seed language - Set wallet seed langage");
   m_cmd_binder.set_handler("help", boost::bind(&simple_wallet::help, this, _1), "Show this help");
 }
 //----------------------------------------------------------------------------------------------------
+bool simple_wallet::set_variable(const std::vector<std::string> &args)
+{
+  if (args.empty())
+  {
+    fail_msg_writer() << "set: needs an argument. available options: seed";
+    return true;
+  }
+  else
+  {
+    if (args[0] == "seed")
+    {
+      if (args.size() == 1)
+      {
+        fail_msg_writer() << "set seed: needs an argument. available options: language";
+        return true;
+      }
+      else if (args[1] == "language")
+      {
+        std::vector<std::string> local_args = args;
+        local_args.erase(local_args.begin(), local_args.begin()+2);
+        seed_set_language(local_args);
+        return true;
+      }
+    }
+  }
+  fail_msg_writer() << "set: unrecognized argument(s)";
+  return true;
+}
+//----------------------------------------------------------------------------------------------------
 bool simple_wallet::set_log(const std::vector<std::string> &args)
 {
   if(args.size() != 1)

src/simplewallet/simplewallet.h

@@ -81,6 +81,17 @@ namespace cryptonote
 
     bool viewkey(const std::vector<std::string> &args = std::vector<std::string>());
     bool seed(const std::vector<std::string> &args = std::vector<std::string>());
+
+    /*!
+     * \brief Sets seed language.
+     *
+     * interactive
+     *   - prompts for password so wallet can be rewritten
+     *   - calls get_mnemonic_language() which prompts for language
+     *
+     * \return success status
+     */
+    bool seed_set_language(const std::vector<std::string> &args = std::vector<std::string>());
     bool help(const std::vector<std::string> &args = std::vector<std::string>());
     bool start_mining(const std::vector<std::string> &args);
     bool stop_mining(const std::vector<std::string> &args);
@@ -96,6 +107,7 @@ namespace cryptonote
     );
     bool print_address(const std::vector<std::string> &args = std::vector<std::string>());
     bool save(const std::vector<std::string> &args);
+    bool set_variable(const std::vector<std::string> &args);
     bool set_log(const std::vector<std::string> &args);
 
     uint64_t get_daemon_blockchain_height(std::string& err);

src/wallet/wallet2.cpp

@@ -570,6 +570,54 @@ void wallet2::load_keys(const std::string& keys_file_name, const std::string& pa
   THROW_WALLET_EXCEPTION_IF(!r, error::invalid_password);
 }
 
+/*!
+ * \brief verify password for default wallet keys file.
+ * \param password       Password to verify
+ *
+ * for verification only
+ * should not mutate state, unlike load_keys()
+ * can be used prior to rewriting wallet keys file, to ensure user has entered the correct password
+ *
+ */
+bool wallet2::verify_password(const std::string& password)
+{
+  const std::string keys_file_name = m_keys_file;
+  wallet2::keys_file_data keys_file_data;
+  std::string buf;
+  bool r = epee::file_io_utils::load_file_to_string(keys_file_name, buf);
+  THROW_WALLET_EXCEPTION_IF(!r, error::file_read_error, keys_file_name);
+
+  // Decrypt the contents
+  r = ::serialization::parse_binary(buf, keys_file_data);
+  THROW_WALLET_EXCEPTION_IF(!r, error::wallet_internal_error, "internal error: failed to deserialize \"" + keys_file_name + '\"');
+  crypto::chacha8_key key;
+  crypto::generate_chacha8_key(password, key);
+  std::string account_data;
+  account_data.resize(keys_file_data.account_data.size());
+  crypto::chacha8(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
+
+  // The contents should be JSON if the wallet follows the new format.
+  rapidjson::Document json;
+  if (json.Parse(account_data.c_str(), keys_file_data.account_data.size()).HasParseError())
+  {
+    // old format before JSON wallet key file format
+  }
+  else
+  {
+    account_data = std::string(json["key_data"].GetString(), json["key_data"].GetString() +
+      json["key_data"].GetStringLength());
+  }
+
+  cryptonote::account_base account_data_check;
+
+  r = epee::serialization::load_t_from_binary(account_data_check, account_data);
+  const cryptonote::account_keys& keys = account_data_check.get_keys();
+
+  r = r && verify_keys(keys.m_view_secret_key,  keys.m_account_address.m_view_public_key);
+  r = r && verify_keys(keys.m_spend_secret_key, keys.m_account_address.m_spend_public_key);
+  return r;
+}
+
 /*!
  * \brief  Generates a wallet or restores one.
  * \param  wallet_        Name of wallet file

src/wallet/wallet2.h

@@ -153,6 +153,11 @@ namespace tools
     void rewrite(const std::string& wallet_name, const std::string& password);
     void load(const std::string& wallet, const std::string& password);
     void store();
+
+    /*!
+     * \brief verifies given password is correct for default wallet keys file
+     */
+    bool verify_password(const std::string& password);
     cryptonote::account_base& get_account(){return m_account;}
 
     // upper_transaction_size_limit as defined below is set to