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-rw-r--r--patches/0001-background-sync.patch4172
1 files changed, 4172 insertions, 0 deletions
diff --git a/patches/0001-background-sync.patch b/patches/0001-background-sync.patch
new file mode 100644
index 0000000..63e95cb
--- /dev/null
+++ b/patches/0001-background-sync.patch
@@ -0,0 +1,4172 @@
+From c7da75fee9bea42a6a741905cf6212db5ea8c54b Mon Sep 17 00:00:00 2001
+From: Czarek Nakamoto <cyjan@mrcyjanek.net>
+Date: Tue, 12 Mar 2024 10:02:23 +0100
+Subject: [PATCH] PATCH: background-sync
+
+---
+ src/cryptonote_basic/account.cpp | 11 +
+ src/cryptonote_basic/account.h | 1 +
+ src/cryptonote_config.h | 3 +
+ src/simplewallet/simplewallet.cpp | 205 +++-
+ src/simplewallet/simplewallet.h | 1 +
+ src/wallet/api/wallet.cpp | 213 ++++-
+ src/wallet/api/wallet.h | 12 +
+ src/wallet/api/wallet2_api.h | 42 +
+ src/wallet/wallet2.cpp | 948 ++++++++++++++++++-
+ src/wallet/wallet2.h | 142 ++-
+ src/wallet/wallet_errors.h | 39 +
+ src/wallet/wallet_rpc_server.cpp | 162 ++++
+ src/wallet/wallet_rpc_server.h | 6 +
+ src/wallet/wallet_rpc_server_commands_defs.h | 64 ++
+ src/wallet/wallet_rpc_server_error_codes.h | 2 +
+ tests/functional_tests/transfer.py | 401 +++++++-
+ tests/functional_tests/util_resources.py | 25 +
+ tests/functional_tests/wallet.py | 43 +-
+ tests/unit_tests/wipeable_string.cpp | 12 +
+ utils/python-rpc/framework/wallet.py | 35 +
+ 20 files changed, 2281 insertions(+), 86 deletions(-)
+
+diff --git a/src/cryptonote_basic/account.cpp b/src/cryptonote_basic/account.cpp
+index 4931c3740..2d556f285 100644
+--- a/src/cryptonote_basic/account.cpp
++++ b/src/cryptonote_basic/account.cpp
+@@ -158,6 +158,17 @@ DISABLE_VS_WARNINGS(4244 4345)
+ m_keys.m_passphrase.wipe();
+ }
+ //-----------------------------------------------------------------
++ void account_base::set_spend_key(const crypto::secret_key& spend_secret_key)
++ {
++ // make sure derived spend public key matches saved public spend key
++ crypto::public_key spend_public_key;
++ crypto::secret_key_to_public_key(spend_secret_key, spend_public_key);
++ CHECK_AND_ASSERT_THROW_MES(m_keys.m_account_address.m_spend_public_key == spend_public_key,
++ "Unexpected derived public spend key");
++
++ m_keys.m_spend_secret_key = spend_secret_key;
++ }
++ //-----------------------------------------------------------------
+ crypto::secret_key account_base::generate(const crypto::secret_key& recovery_key, bool recover, bool two_random)
+ {
+ crypto::secret_key first = generate_keys(m_keys.m_account_address.m_spend_public_key, m_keys.m_spend_secret_key, recovery_key, recover);
+diff --git a/src/cryptonote_basic/account.h b/src/cryptonote_basic/account.h
+index 0099ebfe7..1f76febce 100644
+--- a/src/cryptonote_basic/account.h
++++ b/src/cryptonote_basic/account.h
+@@ -101,6 +101,7 @@ namespace cryptonote
+ bool store(const std::string& file_path);
+
+ void forget_spend_key();
++ void set_spend_key(const crypto::secret_key& spend_secret_key);
+ const std::vector<crypto::secret_key> &get_multisig_keys() const { return m_keys.m_multisig_keys; }
+
+ void encrypt_keys(const crypto::chacha_key &key) { m_keys.encrypt(key); }
+diff --git a/src/cryptonote_config.h b/src/cryptonote_config.h
+index 8e1a07110..cf50b2adc 100644
+--- a/src/cryptonote_config.h
++++ b/src/cryptonote_config.h
+@@ -233,6 +233,7 @@ namespace config
+ } }; // Bender's nightmare
+ std::string const GENESIS_TX = "013c01ff0001ffffffffffff03029b2e4c0281c0b02e7c53291a94d1d0cbff8883f8024f5142ee494ffbbd08807121017767aafcde9be00dcfd098715ebcf7f410daebc582fda69d24a28e9d0bc890d1";
+ uint32_t const GENESIS_NONCE = 10000;
++ std::string const BACKGROUND_WALLET_SUFFIX = ".background";
+
+ // Hash domain separators
+ const char HASH_KEY_BULLETPROOF_EXPONENT[] = "bulletproof";
+@@ -243,6 +244,8 @@ namespace config
+ const unsigned char HASH_KEY_ENCRYPTED_PAYMENT_ID = 0x8d;
+ const unsigned char HASH_KEY_WALLET = 0x8c;
+ const unsigned char HASH_KEY_WALLET_CACHE = 0x8d;
++ const unsigned char HASH_KEY_BACKGROUND_CACHE = 0x8e;
++ const unsigned char HASH_KEY_BACKGROUND_KEYS_FILE = 0x8f;
+ const unsigned char HASH_KEY_RPC_PAYMENT_NONCE = 0x58;
+ const unsigned char HASH_KEY_MEMORY = 'k';
+ const unsigned char HASH_KEY_MULTISIG[] = {'M', 'u', 'l', 't' , 'i', 's', 'i', 'g', 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
+diff --git a/src/simplewallet/simplewallet.cpp b/src/simplewallet/simplewallet.cpp
+index f2eaf6b13..341b0e448 100644
+--- a/src/simplewallet/simplewallet.cpp
++++ b/src/simplewallet/simplewallet.cpp
+@@ -155,6 +155,17 @@ typedef cryptonote::simple_wallet sw;
+ } \
+ } while(0)
+
++#define CHECK_IF_BACKGROUND_SYNCING(msg) \
++ do \
++ { \
++ if (m_wallet->is_background_wallet() || m_wallet->is_background_syncing()) \
++ { \
++ std::string type = m_wallet->is_background_wallet() ? "background wallet" : "background syncing wallet"; \
++ fail_msg_writer() << boost::format(tr("%s %s")) % type % msg; \
++ return false; \
++ } \
++ } while (0)
++
+ enum TransferType {
+ Transfer,
+ TransferLocked,
+@@ -332,7 +343,7 @@ namespace
+ auto pwd_container = tools::password_container::prompt(verify, prompt);
+ if (!pwd_container)
+ {
+- tools::fail_msg_writer() << sw::tr("failed to read wallet password");
++ tools::fail_msg_writer() << sw::tr("failed to read password");
+ }
+ return pwd_container;
+ }
+@@ -342,6 +353,11 @@ namespace
+ return password_prompter(verify ? sw::tr("Enter a new password for the wallet") : sw::tr("Wallet password"), verify);
+ }
+
++ boost::optional<tools::password_container> background_sync_cache_password_prompter(bool verify)
++ {
++ return password_prompter(verify ? sw::tr("Enter a custom password for the background sync cache") : sw::tr("Background sync cache password"), verify);
++ }
++
+ inline std::string interpret_rpc_response(bool ok, const std::string& status)
+ {
+ std::string err;
+@@ -459,6 +475,41 @@ namespace
+ return "invalid";
+ }
+
++ const struct
++ {
++ const char *name;
++ tools::wallet2::BackgroundSyncType background_sync_type;
++ } background_sync_type_names[] =
++ {
++ { "off", tools::wallet2::BackgroundSyncOff },
++ { "reuse-wallet-password", tools::wallet2::BackgroundSyncReusePassword },
++ { "custom-background-password", tools::wallet2::BackgroundSyncCustomPassword },
++ };
++
++ bool parse_background_sync_type(const std::string &s, tools::wallet2::BackgroundSyncType &background_sync_type)
++ {
++ for (size_t n = 0; n < sizeof(background_sync_type_names) / sizeof(background_sync_type_names[0]); ++n)
++ {
++ if (s == background_sync_type_names[n].name)
++ {
++ background_sync_type = background_sync_type_names[n].background_sync_type;
++ return true;
++ }
++ }
++ fail_msg_writer() << cryptonote::simple_wallet::tr("failed to parse background sync type");
++ return false;
++ }
++
++ std::string get_background_sync_type_name(tools::wallet2::BackgroundSyncType type)
++ {
++ for (size_t n = 0; n < sizeof(background_sync_type_names) / sizeof(background_sync_type_names[0]); ++n)
++ {
++ if (type == background_sync_type_names[n].background_sync_type)
++ return background_sync_type_names[n].name;
++ }
++ return "invalid";
++ }
++
+ std::string get_version_string(uint32_t version)
+ {
+ return boost::lexical_cast<std::string>(version >> 16) + "." + boost::lexical_cast<std::string>(version & 0xffff);
+@@ -812,6 +863,7 @@ bool simple_wallet::spendkey(const std::vector<std::string> &args/* = std::vecto
+ fail_msg_writer() << tr("wallet is watch-only and has no spend key");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("has no spend key");
+ // don't log
+ PAUSE_READLINE();
+ if (m_wallet->key_on_device()) {
+@@ -843,6 +895,7 @@ bool simple_wallet::print_seed(bool encrypted)
+ fail_msg_writer() << tr("wallet is watch-only and has no seed");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("has no seed");
+
+ multisig = m_wallet->multisig(&ready);
+ if (multisig)
+@@ -920,6 +973,7 @@ bool simple_wallet::seed_set_language(const std::vector<std::string> &args/* = s
+ fail_msg_writer() << tr("wallet is watch-only and has no seed");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("has no seed");
+
+ epee::wipeable_string password;
+ {
+@@ -1066,6 +1120,7 @@ bool simple_wallet::prepare_multisig_main(const std::vector<std::string> &args,
+ fail_msg_writer() << tr("wallet is watch-only and cannot be made multisig");
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("cannot be made multisig");
+
+ if(m_wallet->get_num_transfer_details())
+ {
+@@ -2202,6 +2257,7 @@ bool simple_wallet::save_known_rings(const std::vector<std::string> &args)
+
+ bool simple_wallet::freeze_thaw(const std::vector<std::string> &args, bool freeze)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot freeze/thaw");
+ if (args.empty())
+ {
+ fail_msg_writer() << boost::format(tr("usage: %s <key_image>|<pubkey>")) % (freeze ? "freeze" : "thaw");
+@@ -2241,6 +2297,7 @@ bool simple_wallet::thaw(const std::vector<std::string> &args)
+
+ bool simple_wallet::frozen(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot see frozen key images");
+ if (args.empty())
+ {
+ size_t ntd = m_wallet->get_num_transfer_details();
+@@ -3012,6 +3069,56 @@ bool simple_wallet::set_track_uses(const std::vector<std::string> &args/* = std:
+ return true;
+ }
+
++bool simple_wallet::setup_background_sync(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
++{
++ if (m_wallet->multisig())
++ {
++ fail_msg_writer() << tr("background sync not implemented for multisig wallet");
++ return true;
++ }
++ if (m_wallet->watch_only())
++ {
++ fail_msg_writer() << tr("background sync not implemented for watch only wallet");
++ return true;
++ }
++ if (m_wallet->key_on_device())
++ {
++ fail_msg_writer() << tr("command not supported by HW wallet");
++ return true;
++ }
++
++ const auto pwd_container = get_and_verify_password();
++ if (pwd_container)
++ {
++ tools::wallet2::BackgroundSyncType background_sync_type;
++ if (!parse_background_sync_type(args[1], background_sync_type))
++ {
++ fail_msg_writer() << tr("invalid option");
++ return true;
++ }
++
++ try
++ {
++ boost::optional<epee::wipeable_string> background_cache_password = boost::none;
++ if (background_sync_type == tools::wallet2::BackgroundSyncCustomPassword)
++ {
++ const auto background_pwd_container = background_sync_cache_password_prompter(true);
++ if (!background_pwd_container)
++ return true;
++ background_cache_password = background_pwd_container->password();
++ }
++
++ LOCK_IDLE_SCOPE();
++ m_wallet->setup_background_sync(background_sync_type, pwd_container->password(), background_cache_password);
++ }
++ catch (const std::exception &e)
++ {
++ fail_msg_writer() << tr("Error setting background sync type: ") << e.what();
++ }
++ }
++ return true;
++}
++
+ bool simple_wallet::set_show_wallet_name_when_locked(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
+ {
+ const auto pwd_container = get_and_verify_password();
+@@ -3244,6 +3351,7 @@ bool simple_wallet::apropos(const std::vector<std::string> &args)
+
+ bool simple_wallet::scan_tx(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot scan tx");
+ if (args.empty())
+ {
+ PRINT_USAGE(USAGE_SCAN_TX);
+@@ -3473,6 +3581,8 @@ simple_wallet::simple_wallet()
+ " Ignore outputs of amount below this threshold when spending.\n "
+ "track-uses <1|0>\n "
+ " Whether to keep track of owned outputs uses.\n "
++ "background-sync <off|reuse-wallet-password|custom-background-password>\n "
++ " Set this to enable scanning in the background with just the view key while the wallet is locked.\n "
+ "setup-background-mining <1|0>\n "
+ " Whether to enable background mining. Set this to support the network and to get a chance to receive new monero.\n "
+ "device-name <device_name[:device_spec]>\n "
+@@ -3891,6 +4001,7 @@ bool simple_wallet::set_variable(const std::vector<std::string> &args)
+ success_msg_writer() << "ignore-outputs-above = " << cryptonote::print_money(m_wallet->ignore_outputs_above());
+ success_msg_writer() << "ignore-outputs-below = " << cryptonote::print_money(m_wallet->ignore_outputs_below());
+ success_msg_writer() << "track-uses = " << m_wallet->track_uses();
++ success_msg_writer() << "background-sync = " << get_background_sync_type_name(m_wallet->background_sync_type());
+ success_msg_writer() << "setup-background-mining = " << setup_background_mining_string;
+ success_msg_writer() << "device-name = " << m_wallet->device_name();
+ success_msg_writer() << "export-format = " << (m_wallet->export_format() == tools::wallet2::ExportFormat::Ascii ? "ascii" : "binary");
+@@ -3909,6 +4020,7 @@ bool simple_wallet::set_variable(const std::vector<std::string> &args)
+ }
+ else
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot change wallet settings");
+
+ #define CHECK_SIMPLE_VARIABLE(name, f, help) do \
+ if (args[0] == name) { \
+@@ -3962,6 +4074,7 @@ bool simple_wallet::set_variable(const std::vector<std::string> &args)
+ CHECK_SIMPLE_VARIABLE("ignore-outputs-above", set_ignore_outputs_above, tr("amount"));
+ CHECK_SIMPLE_VARIABLE("ignore-outputs-below", set_ignore_outputs_below, tr("amount"));
+ CHECK_SIMPLE_VARIABLE("track-uses", set_track_uses, tr("0 or 1"));
++ CHECK_SIMPLE_VARIABLE("background-sync", setup_background_sync, tr("off (default); reuse-wallet-password (reuse the wallet password to encrypt the background cache); custom-background-password (use a custom background password to encrypt the background cache)"));
+ CHECK_SIMPLE_VARIABLE("show-wallet-name-when-locked", set_show_wallet_name_when_locked, tr("1 or 0"));
+ CHECK_SIMPLE_VARIABLE("inactivity-lock-timeout", set_inactivity_lock_timeout, tr("unsigned integer (seconds, 0 to disable)"));
+ CHECK_SIMPLE_VARIABLE("setup-background-mining", set_setup_background_mining, tr("1/yes or 0/no"));
+@@ -4915,7 +5028,10 @@ std::string simple_wallet::get_mnemonic_language()
+ //----------------------------------------------------------------------------------------------------
+ boost::optional<tools::password_container> simple_wallet::get_and_verify_password() const
+ {
+- auto pwd_container = default_password_prompter(m_wallet_file.empty());
++ const bool verify = m_wallet_file.empty();
++ auto pwd_container = (m_wallet->is_background_wallet() && m_wallet->background_sync_type() == tools::wallet2::BackgroundSyncCustomPassword)
++ ? background_sync_cache_password_prompter(verify)
++ : default_password_prompter(verify);
+ if (!pwd_container)
+ return boost::none;
+
+@@ -5218,6 +5334,8 @@ boost::optional<epee::wipeable_string> simple_wallet::open_wallet(const boost::p
+ prefix = tr("Opened watch-only wallet");
+ else if (m_wallet->multisig(&ready, &threshold, &total))
+ prefix = (boost::format(tr("Opened %u/%u multisig wallet%s")) % threshold % total % (ready ? "" : " (not yet finalized)")).str();
++ else if (m_wallet->is_background_wallet())
++ prefix = tr("Opened background wallet");
+ else
+ prefix = tr("Opened wallet");
+ message_writer(console_color_white, true) <<
+@@ -5426,6 +5544,10 @@ void simple_wallet::stop_background_mining()
+ //----------------------------------------------------------------------------------------------------
+ void simple_wallet::check_background_mining(const epee::wipeable_string &password)
+ {
++ // Background mining can be toggled from the main wallet
++ if (m_wallet->is_background_wallet() || m_wallet->is_background_syncing())
++ return;
++
+ tools::wallet2::BackgroundMiningSetupType setup = m_wallet->setup_background_mining();
+ if (setup == tools::wallet2::BackgroundMiningNo)
+ {
+@@ -6290,6 +6412,7 @@ bool simple_wallet::show_blockchain_height(const std::vector<std::string>& args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::rescan_spent(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot rescan spent");
+ if (!m_wallet->is_trusted_daemon())
+ {
+ fail_msg_writer() << tr("this command requires a trusted daemon. Enable with --trusted-daemon");
+@@ -6547,10 +6670,27 @@ void simple_wallet::check_for_inactivity_lock(bool user)
+ " || ||" << std::endl <<
+ "" << std::endl;
+ }
++
++ bool started_background_sync = false;
++ if (!m_wallet->is_background_wallet() &&
++ m_wallet->background_sync_type() != tools::wallet2::BackgroundSyncOff)
++ {
++ LOCK_IDLE_SCOPE();
++ m_wallet->start_background_sync();
++ started_background_sync = true;
++ }
++
+ while (1)
+ {
+ const char *inactivity_msg = user ? "" : tr("Locked due to inactivity.");
+- tools::msg_writer() << inactivity_msg << (inactivity_msg[0] ? " " : "") << tr("The wallet password is required to unlock the console.");
++ tools::msg_writer() << inactivity_msg << (inactivity_msg[0] ? " " : "") << (
++ (m_wallet->is_background_wallet() && m_wallet->background_sync_type() == tools::wallet2::BackgroundSyncCustomPassword)
++ ? tr("The background password is required to unlock the console.")
++ : tr("The wallet password is required to unlock the console.")
++ );
++
++ if (m_wallet->is_background_syncing())
++ tools::msg_writer() << tr("\nSyncing in the background while locked...") << std::endl;
+
+ const bool show_wallet_name = m_wallet->show_wallet_name_when_locked();
+ if (show_wallet_name)
+@@ -6563,8 +6703,16 @@ void simple_wallet::check_for_inactivity_lock(bool user)
+ }
+ try
+ {
+- if (get_and_verify_password())
++ const auto pwd_container = get_and_verify_password();
++ if (pwd_container)
++ {
++ if (started_background_sync)
++ {
++ LOCK_IDLE_SCOPE();
++ m_wallet->stop_background_sync(pwd_container->password());
++ }
+ break;
++ }
+ }
+ catch (...) { /* do nothing, just let the loop loop */ }
+ }
+@@ -6591,6 +6739,7 @@ bool simple_wallet::on_command(bool (simple_wallet::*cmd)(const std::vector<std:
+ bool simple_wallet::transfer_main(int transfer_type, const std::vector<std::string> &args_, bool called_by_mms)
+ {
+ // "transfer [index=<N1>[,<N2>,...]] [<priority>] [<ring_size>] <address> <amount> [<payment_id>]"
++ CHECK_IF_BACKGROUND_SYNCING("cannot transfer");
+ if (!try_connect_to_daemon())
+ return false;
+
+@@ -7064,6 +7213,7 @@ bool simple_wallet::transfer_main(int transfer_type, const std::vector<std::stri
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::transfer(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot transfer");
+ if (args_.size() < 1)
+ {
+ PRINT_USAGE(USAGE_TRANSFER);
+@@ -7075,6 +7225,7 @@ bool simple_wallet::transfer(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::locked_transfer(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot transfer");
+ if (args_.size() < 1)
+ {
+ PRINT_USAGE(USAGE_LOCKED_TRANSFER);
+@@ -7086,6 +7237,7 @@ bool simple_wallet::locked_transfer(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::locked_sweep_all(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ if (args_.size() < 1)
+ {
+ PRINT_USAGE(USAGE_LOCKED_SWEEP_ALL);
+@@ -7098,6 +7250,7 @@ bool simple_wallet::locked_sweep_all(const std::vector<std::string> &args_)
+
+ bool simple_wallet::sweep_unmixable(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ if (!try_connect_to_daemon())
+ return true;
+
+@@ -7205,6 +7358,7 @@ bool simple_wallet::sweep_unmixable(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::sweep_main(uint32_t account, uint64_t below, bool locked, const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ auto print_usage = [this, account, below]()
+ {
+ if (below)
+@@ -7521,6 +7675,7 @@ bool simple_wallet::sweep_main(uint32_t account, uint64_t below, bool locked, co
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::sweep_single(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ if (!try_connect_to_daemon())
+ return true;
+
+@@ -7759,12 +7914,14 @@ bool simple_wallet::sweep_single(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::sweep_all(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ sweep_main(m_current_subaddress_account, 0, false, args_);
+ return true;
+ }
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::sweep_account(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ auto local_args = args_;
+ if (local_args.empty())
+ {
+@@ -7785,6 +7942,7 @@ bool simple_wallet::sweep_account(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::sweep_below(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sweep");
+ uint64_t below = 0;
+ if (args_.size() < 1)
+ {
+@@ -7803,6 +7961,7 @@ bool simple_wallet::sweep_below(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::donate(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot donate");
+ std::vector<std::string> local_args = args_;
+ if(local_args.empty() || local_args.size() > 5)
+ {
+@@ -7864,6 +8023,7 @@ bool simple_wallet::donate(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::accept_loaded_tx(const std::function<size_t()> get_num_txes, const std::function<const tools::wallet2::tx_construction_data&(size_t)> &get_tx, const std::string &extra_message)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot load tx");
+ // gather info to ask the user
+ uint64_t amount = 0, amount_to_dests = 0, change = 0;
+ size_t min_ring_size = ~0;
+@@ -8044,6 +8204,7 @@ bool simple_wallet::sign_transfer(const std::vector<std::string> &args_)
+ fail_msg_writer() << tr("This is a watch only wallet");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("cannot sign transfer");
+
+ bool export_raw = false;
+ std::string unsigned_filename = "unsigned_monero_tx";
+@@ -8151,6 +8312,8 @@ std::string get_tx_key_stream(crypto::secret_key tx_key, std::vector<crypto::sec
+
+ bool simple_wallet::get_tx_key(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get tx key");
++
+ std::vector<std::string> local_args = args_;
+
+ if (m_wallet->key_on_device() && m_wallet->get_account().get_device().get_type() != hw::device::TREZOR)
+@@ -8191,6 +8354,8 @@ bool simple_wallet::get_tx_key(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::set_tx_key(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot set tx key");
++
+ std::vector<std::string> local_args = args_;
+
+ if(local_args.size() != 2 && local_args.size() != 3) {
+@@ -8267,6 +8432,8 @@ bool simple_wallet::set_tx_key(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::get_tx_proof(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get tx proof");
++
+ if (args.size() != 2 && args.size() != 3)
+ {
+ PRINT_USAGE(USAGE_GET_TX_PROOF);
+@@ -8473,6 +8640,7 @@ bool simple_wallet::check_tx_proof(const std::vector<std::string> &args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::get_spend_proof(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get spend proof");
+ if (m_wallet->key_on_device())
+ {
+ fail_msg_writer() << tr("command not supported by HW wallet");
+@@ -8557,6 +8725,7 @@ bool simple_wallet::check_spend_proof(const std::vector<std::string> &args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::get_reserve_proof(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get reserve proof");
+ if (m_wallet->key_on_device())
+ {
+ fail_msg_writer() << tr("command not supported by HW wallet");
+@@ -9243,6 +9412,8 @@ bool simple_wallet::unspent_outputs(const std::vector<std::string> &args_)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::rescan_blockchain(const std::vector<std::string> &args_)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot rescan");
++
+ uint64_t start_height = 0;
+ ResetType reset_type = ResetSoft;
+
+@@ -9540,6 +9711,7 @@ bool simple_wallet::account(const std::vector<std::string> &args/* = std::vector
+ if (command == "new")
+ {
+ // create a new account and switch to it
++ CHECK_IF_BACKGROUND_SYNCING("cannot create new account");
+ std::string label = boost::join(local_args, " ");
+ if (label.empty())
+ label = tr("(Untitled account)");
+@@ -9570,6 +9742,7 @@ bool simple_wallet::account(const std::vector<std::string> &args/* = std::vector
+ else if (command == "label" && local_args.size() >= 1)
+ {
+ // set label of the specified account
++ CHECK_IF_BACKGROUND_SYNCING("cannot modify account");
+ uint32_t index_major;
+ if (!epee::string_tools::get_xtype_from_string(index_major, local_args[0]))
+ {
+@@ -9591,6 +9764,7 @@ bool simple_wallet::account(const std::vector<std::string> &args/* = std::vector
+ }
+ else if (command == "tag" && local_args.size() >= 2)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot modify account");
+ const std::string tag = local_args[0];
+ std::set<uint32_t> account_indices;
+ for (size_t i = 1; i < local_args.size(); ++i)
+@@ -9615,6 +9789,7 @@ bool simple_wallet::account(const std::vector<std::string> &args/* = std::vector
+ }
+ else if (command == "untag" && local_args.size() >= 1)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot modify account");
+ std::set<uint32_t> account_indices;
+ for (size_t i = 0; i < local_args.size(); ++i)
+ {
+@@ -9638,6 +9813,7 @@ bool simple_wallet::account(const std::vector<std::string> &args/* = std::vector
+ }
+ else if (command == "tag_description" && local_args.size() >= 1)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot modify account");
+ const std::string tag = local_args[0];
+ std::string description;
+ if (local_args.size() > 1)
+@@ -9755,6 +9931,7 @@ bool simple_wallet::print_address(const std::vector<std::string> &args/* = std::
+ }
+ else if (local_args[0] == "new")
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot add address");
+ local_args.erase(local_args.begin());
+ std::string label;
+ if (local_args.size() > 0)
+@@ -9767,6 +9944,7 @@ bool simple_wallet::print_address(const std::vector<std::string> &args/* = std::
+ }
+ else if (local_args[0] == "mnew")
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot add addresses");
+ local_args.erase(local_args.begin());
+ if (local_args.size() != 1)
+ {
+@@ -9792,6 +9970,7 @@ bool simple_wallet::print_address(const std::vector<std::string> &args/* = std::
+ }
+ else if (local_args[0] == "one-off")
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot add address");
+ local_args.erase(local_args.begin());
+ std::string label;
+ if (local_args.size() != 2)
+@@ -9810,6 +9989,7 @@ bool simple_wallet::print_address(const std::vector<std::string> &args/* = std::
+ }
+ else if (local_args.size() >= 2 && local_args[0] == "label")
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot modify address");
+ if (!epee::string_tools::get_xtype_from_string(index, local_args[1]))
+ {
+ fail_msg_writer() << tr("failed to parse index: ") << local_args[1];
+@@ -9956,6 +10136,8 @@ bool simple_wallet::print_integrated_address(const std::vector<std::string> &arg
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::address_book(const std::vector<std::string> &args/* = std::vector<std::string>()*/)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get address book");
++
+ if (args.size() == 0)
+ {
+ }
+@@ -10016,6 +10198,8 @@ bool simple_wallet::address_book(const std::vector<std::string> &args/* = std::v
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::set_tx_note(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot set tx note");
++
+ if (args.size() == 0)
+ {
+ PRINT_USAGE(USAGE_SET_TX_NOTE);
+@@ -10044,6 +10228,8 @@ bool simple_wallet::set_tx_note(const std::vector<std::string> &args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::get_tx_note(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get tx note");
++
+ if (args.size() != 1)
+ {
+ PRINT_USAGE(USAGE_GET_TX_NOTE);
+@@ -10069,6 +10255,8 @@ bool simple_wallet::get_tx_note(const std::vector<std::string> &args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::set_description(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot set description");
++
+ // 0 arguments allowed, for setting the description to empty string
+
+ std::string description = "";
+@@ -10085,6 +10273,8 @@ bool simple_wallet::set_description(const std::vector<std::string> &args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::get_description(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot get description");
++
+ if (args.size() != 0)
+ {
+ PRINT_USAGE(USAGE_GET_DESCRIPTION);
+@@ -10143,6 +10333,8 @@ bool simple_wallet::wallet_info(const std::vector<std::string> &args)
+ type = tr("Watch only");
+ else if (m_wallet->multisig(&ready, &threshold, &total))
+ type = (boost::format(tr("%u/%u multisig%s")) % threshold % total % (ready ? "" : " (not yet finalized)")).str();
++ else if (m_wallet->is_background_wallet())
++ type = tr("Background wallet");
+ else
+ type = tr("Normal");
+ message_writer() << tr("Type: ") << type;
+@@ -10154,6 +10346,7 @@ bool simple_wallet::wallet_info(const std::vector<std::string> &args)
+ //----------------------------------------------------------------------------------------------------
+ bool simple_wallet::sign(const std::vector<std::string> &args)
+ {
++ CHECK_IF_BACKGROUND_SYNCING("cannot sign");
+ if (m_wallet->key_on_device())
+ {
+ fail_msg_writer() << tr("command not supported by HW wallet");
+@@ -10261,6 +10454,7 @@ bool simple_wallet::export_key_images(const std::vector<std::string> &args_)
+ fail_msg_writer() << tr("command not supported by HW wallet");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("cannot export key images");
+ auto args = args_;
+
+ if (m_wallet->watch_only())
+@@ -10314,6 +10508,7 @@ bool simple_wallet::import_key_images(const std::vector<std::string> &args)
+ fail_msg_writer() << tr("command not supported by HW wallet");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("cannot import key images");
+ if (!m_wallet->is_trusted_daemon())
+ {
+ fail_msg_writer() << tr("this command requires a trusted daemon. Enable with --trusted-daemon");
+@@ -10422,6 +10617,7 @@ bool simple_wallet::export_outputs(const std::vector<std::string> &args_)
+ fail_msg_writer() << tr("command not supported by HW wallet");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("cannot export outputs");
+ auto args = args_;
+
+ bool all = false;
+@@ -10471,6 +10667,7 @@ bool simple_wallet::import_outputs(const std::vector<std::string> &args)
+ fail_msg_writer() << tr("command not supported by HW wallet");
+ return true;
+ }
++ CHECK_IF_BACKGROUND_SYNCING("cannot import outputs");
+ if (args.size() != 1)
+ {
+ PRINT_USAGE(USAGE_IMPORT_OUTPUTS);
+diff --git a/src/simplewallet/simplewallet.h b/src/simplewallet/simplewallet.h
+index 7c45d45e8..79c739cdd 100644
+--- a/src/simplewallet/simplewallet.h
++++ b/src/simplewallet/simplewallet.h
+@@ -147,6 +147,7 @@ namespace cryptonote
+ bool set_ignore_outputs_above(const std::vector<std::string> &args = std::vector<std::string>());
+ bool set_ignore_outputs_below(const std::vector<std::string> &args = std::vector<std::string>());
+ bool set_track_uses(const std::vector<std::string> &args = std::vector<std::string>());
++ bool setup_background_sync(const std::vector<std::string> &args = std::vector<std::string>());
+ bool set_show_wallet_name_when_locked(const std::vector<std::string> &args = std::vector<std::string>());
+ bool set_inactivity_lock_timeout(const std::vector<std::string> &args = std::vector<std::string>());
+ bool set_setup_background_mining(const std::vector<std::string> &args = std::vector<std::string>());
+diff --git a/src/wallet/api/wallet.cpp b/src/wallet/api/wallet.cpp
+index 472f05016..1a9c6f674 100644
+--- a/src/wallet/api/wallet.cpp
++++ b/src/wallet/api/wallet.cpp
+@@ -54,6 +54,40 @@ using namespace cryptonote;
+ #undef MONERO_DEFAULT_LOG_CATEGORY
+ #define MONERO_DEFAULT_LOG_CATEGORY "WalletAPI"
+
++#define LOCK_REFRESH() \
++ bool refresh_enabled = m_refreshEnabled; \
++ m_refreshEnabled = false; \
++ m_wallet->stop(); \
++ m_refreshCV.notify_one(); \
++ boost::mutex::scoped_lock lock(m_refreshMutex); \
++ boost::mutex::scoped_lock lock2(m_refreshMutex2); \
++ epee::misc_utils::auto_scope_leave_caller scope_exit_handler = epee::misc_utils::create_scope_leave_handler([&](){ \
++ /* m_refreshMutex's still locked here */ \
++ if (refresh_enabled) \
++ startRefresh(); \
++ })
++
++#define PRE_VALIDATE_BACKGROUND_SYNC() \
++ do \
++ { \
++ clearStatus(); \
++ if (m_wallet->key_on_device()) \
++ { \
++ setStatusError(tr("HW wallet cannot use background sync")); \
++ return false; \
++ } \
++ if (m_wallet->watch_only()) \
++ { \
++ setStatusError(tr("View only wallet cannot use background sync")); \
++ return false; \
++ } \
++ if (m_wallet->multisig()) \
++ { \
++ setStatusError(tr("Multisig wallet cannot use background sync")); \
++ return false; \
++ } \
++ } while (0)
++
+ namespace Monero {
+
+ namespace {
+@@ -814,6 +848,8 @@ bool WalletImpl::close(bool store)
+
+ std::string WalletImpl::seed(const std::string& seed_offset) const
+ {
++ if (checkBackgroundSync("cannot get seed"))
++ return std::string();
+ epee::wipeable_string seed;
+ if (m_wallet)
+ m_wallet->get_seed(seed, seed_offset);
+@@ -876,6 +912,8 @@ std::string WalletImpl::getSeedLanguage() const
+
+ void WalletImpl::setSeedLanguage(const std::string &arg)
+ {
++ if (checkBackgroundSync("cannot set seed language"))
++ return;
+ m_wallet->set_seed_language(arg);
+ }
+
+@@ -899,6 +937,8 @@ void WalletImpl::statusWithErrorString(int& status, std::string& errorString) co
+
+ bool WalletImpl::setPassword(const std::string &password)
+ {
++ if (checkBackgroundSync("cannot change password"))
++ return false;
+ clearStatus();
+ try {
+ m_wallet->change_password(m_wallet->get_wallet_file(), m_password, password);
+@@ -1059,6 +1099,8 @@ bool WalletImpl::lightWalletImportWalletRequest(std::string &payment_id, uint64_
+
+ void WalletImpl::setRefreshFromBlockHeight(uint64_t refresh_from_block_height)
+ {
++ if (checkBackgroundSync("cannot change refresh height"))
++ return;
+ m_wallet->set_refresh_from_block_height(refresh_from_block_height);
+ }
+
+@@ -1176,6 +1218,8 @@ void WalletImpl::refreshAsync()
+
+ bool WalletImpl::rescanBlockchain()
+ {
++ if (checkBackgroundSync("cannot rescan blockchain"))
++ return false;
+ clearStatus();
+ m_refreshShouldRescan = true;
+ doRefresh();
+@@ -1184,6 +1228,8 @@ bool WalletImpl::rescanBlockchain()
+
+ void WalletImpl::rescanBlockchainAsync()
+ {
++ if (checkBackgroundSync("cannot rescan blockchain"))
++ return;
+ m_refreshShouldRescan = true;
+ refreshAsync();
+ }
+@@ -1207,7 +1253,7 @@ int WalletImpl::autoRefreshInterval() const
+ UnsignedTransaction *WalletImpl::loadUnsignedTx(const std::string &unsigned_filename) {
+ clearStatus();
+ UnsignedTransactionImpl * transaction = new UnsignedTransactionImpl(*this);
+- if (!m_wallet->load_unsigned_tx(unsigned_filename, transaction->m_unsigned_tx_set)){
++ if (checkBackgroundSync("cannot load tx") || !m_wallet->load_unsigned_tx(unsigned_filename, transaction->m_unsigned_tx_set)){
+ setStatusError(tr("Failed to load unsigned transactions"));
+ transaction->m_status = UnsignedTransaction::Status::Status_Error;
+ transaction->m_errorString = errorString();
+@@ -1227,6 +1273,8 @@ UnsignedTransaction *WalletImpl::loadUnsignedTx(const std::string &unsigned_file
+
+ bool WalletImpl::submitTransaction(const string &fileName) {
+ clearStatus();
++ if (checkBackgroundSync("cannot submit tx"))
++ return false;
+ std::unique_ptr<PendingTransactionImpl> transaction(new PendingTransactionImpl(*this));
+
+ bool r = m_wallet->load_tx(fileName, transaction->m_pending_tx);
+@@ -1250,6 +1298,8 @@ bool WalletImpl::exportKeyImages(const string &filename, bool all)
+ setStatusError(tr("Wallet is view only"));
+ return false;
+ }
++ if (checkBackgroundSync("cannot export key images"))
++ return false;
+
+ try
+ {
+@@ -1270,6 +1320,8 @@ bool WalletImpl::exportKeyImages(const string &filename, bool all)
+
+ bool WalletImpl::importKeyImages(const string &filename)
+ {
++ if (checkBackgroundSync("cannot import key images"))
++ return false;
+ if (!trustedDaemon()) {
+ setStatusError(tr("Key images can only be imported with a trusted daemon"));
+ return false;
+@@ -1293,6 +1345,8 @@ bool WalletImpl::importKeyImages(const string &filename)
+
+ bool WalletImpl::exportOutputs(const string &filename, bool all)
+ {
++ if (checkBackgroundSync("cannot export outputs"))
++ return false;
+ if (m_wallet->key_on_device())
+ {
+ setStatusError(string(tr("Not supported on HW wallets.")) + filename);
+@@ -1323,6 +1377,8 @@ bool WalletImpl::exportOutputs(const string &filename, bool all)
+
+ bool WalletImpl::importOutputs(const string &filename)
+ {
++ if (checkBackgroundSync("cannot import outputs"))
++ return false;
+ if (m_wallet->key_on_device())
+ {
+ setStatusError(string(tr("Not supported on HW wallets.")) + filename);
+@@ -1355,6 +1411,8 @@ bool WalletImpl::importOutputs(const string &filename)
+
+ bool WalletImpl::scanTransactions(const std::vector<std::string> &txids)
+ {
++ if (checkBackgroundSync("cannot scan transactions"))
++ return false;
+ if (txids.empty())
+ {
+ setStatusError(string(tr("Failed to scan transactions: no transaction ids provided.")));
+@@ -1393,8 +1451,86 @@ bool WalletImpl::scanTransactions(const std::vector<std::string> &txids)
+ return true;
+ }
+
++bool WalletImpl::setupBackgroundSync(const Wallet::BackgroundSyncType background_sync_type, const std::string &wallet_password, const optional<std::string> &background_cache_password)
++{
++ try
++ {
++ PRE_VALIDATE_BACKGROUND_SYNC();
++
++ tools::wallet2::BackgroundSyncType bgs_type;
++ switch (background_sync_type)
++ {
++ case Wallet::BackgroundSync_Off: bgs_type = tools::wallet2::BackgroundSyncOff; break;
++ case Wallet::BackgroundSync_ReusePassword: bgs_type = tools::wallet2::BackgroundSyncReusePassword; break;
++ case Wallet::BackgroundSync_CustomPassword: bgs_type = tools::wallet2::BackgroundSyncCustomPassword; break;
++ default: setStatusError(tr("Unknown background sync type")); return false;
++ }
++
++ boost::optional<epee::wipeable_string> bgc_password = background_cache_password
++ ? boost::optional<epee::wipeable_string>(*background_cache_password)
++ : boost::none;
++
++ LOCK_REFRESH();
++ m_wallet->setup_background_sync(bgs_type, wallet_password, bgc_password);
++ }
++ catch (const std::exception &e)
++ {
++ LOG_ERROR("Failed to setup background sync: " << e.what());
++ setStatusError(string(tr("Failed to setup background sync: ")) + e.what());
++ return false;
++ }
++ return true;
++}
++
++Wallet::BackgroundSyncType WalletImpl::getBackgroundSyncType() const
++{
++ switch (m_wallet->background_sync_type())
++ {
++ case tools::wallet2::BackgroundSyncOff: return Wallet::BackgroundSync_Off;
++ case tools::wallet2::BackgroundSyncReusePassword: return Wallet::BackgroundSync_ReusePassword;
++ case tools::wallet2::BackgroundSyncCustomPassword: return Wallet::BackgroundSync_CustomPassword;
++ default: setStatusError(tr("Unknown background sync type")); return Wallet::BackgroundSync_Off;
++ }
++}
++
++bool WalletImpl::startBackgroundSync()
++{
++ try
++ {
++ PRE_VALIDATE_BACKGROUND_SYNC();
++ LOCK_REFRESH();
++ m_wallet->start_background_sync();
++ }
++ catch (const std::exception &e)
++ {
++ LOG_ERROR("Failed to start background sync: " << e.what());
++ setStatusError(string(tr("Failed to start background sync: ")) + e.what());
++ return false;
++ }
++ return true;
++}
++
++bool WalletImpl::stopBackgroundSync(const std::string &wallet_password)
++{
++ try
++ {
++ PRE_VALIDATE_BACKGROUND_SYNC();
++ LOCK_REFRESH();
++ m_wallet->stop_background_sync(epee::wipeable_string(wallet_password));
++ }
++ catch (const std::exception &e)
++ {
++ LOG_ERROR("Failed to stop background sync: " << e.what());
++ setStatusError(string(tr("Failed to stop background sync: ")) + e.what());
++ return false;
++ }
++ return true;
++}
++
+ void WalletImpl::addSubaddressAccount(const std::string& label)
+ {
++ if (checkBackgroundSync("cannot add account"))
++ return;
+ m_wallet->add_subaddress_account(label);
+ }
+ size_t WalletImpl::numSubaddressAccounts() const
+@@ -1407,10 +1543,14 @@ size_t WalletImpl::numSubaddresses(uint32_t accountIndex) const
+ }
+ void WalletImpl::addSubaddress(uint32_t accountIndex, const std::string& label)
+ {
++ if (checkBackgroundSync("cannot add subbaddress"))
++ return;
+ m_wallet->add_subaddress(accountIndex, label);
+ }
+ std::string WalletImpl::getSubaddressLabel(uint32_t accountIndex, uint32_t addressIndex) const
+ {
++ if (checkBackgroundSync("cannot get subbaddress label"))
++ return "";
+ try
+ {
+ return m_wallet->get_subaddress_label({accountIndex, addressIndex});
+@@ -1424,6 +1564,8 @@ std::string WalletImpl::getSubaddressLabel(uint32_t accountIndex, uint32_t addre
+ }
+ void WalletImpl::setSubaddressLabel(uint32_t accountIndex, uint32_t addressIndex, const std::string &label)
+ {
++ if (checkBackgroundSync("cannot set subbaddress label"))
++ return;
+ try
+ {
+ return m_wallet->set_subaddress_label({accountIndex, addressIndex}, label);
+@@ -1437,12 +1579,16 @@ void WalletImpl::setSubaddressLabel(uint32_t accountIndex, uint32_t addressIndex
+
+ MultisigState WalletImpl::multisig() const {
+ MultisigState state;
++ if (checkBackgroundSync("cannot use multisig"))
++ return state;
+ state.isMultisig = m_wallet->multisig(&state.isReady, &state.threshold, &state.total);
+
+ return state;
+ }
+
+ string WalletImpl::getMultisigInfo() const {
++ if (checkBackgroundSync("cannot use multisig"))
++ return string();
+ try {
+ clearStatus();
+ return m_wallet->get_multisig_first_kex_msg();
+@@ -1455,6 +1601,8 @@ string WalletImpl::getMultisigInfo() const {
+ }
+
+ string WalletImpl::makeMultisig(const vector<string>& info, const uint32_t threshold) {
++ if (checkBackgroundSync("cannot make multisig"))
++ return string();
+ try {
+ clearStatus();
+
+@@ -1595,6 +1743,9 @@ PendingTransaction *WalletImpl::createTransactionMultDest(const std::vector<stri
+ PendingTransactionImpl * transaction = new PendingTransactionImpl(*this);
+
+ do {
++ if (checkBackgroundSync("cannot create transactions"))
++ break;
++
+ std::vector<uint8_t> extra;
+ std::string extra_nonce;
+ vector<cryptonote::tx_destination_entry> dsts;
+@@ -1761,6 +1912,9 @@ PendingTransaction *WalletImpl::createSweepUnmixableTransaction()
+ PendingTransactionImpl * transaction = new PendingTransactionImpl(*this);
+
+ do {
++ if (checkBackgroundSync("cannot sweep"))
++ break;
++
+ try {
+ transaction->m_pending_tx = m_wallet->create_unmixable_sweep_transactions();
+ pendingTxPostProcess(transaction);
+@@ -1894,11 +2048,15 @@ uint32_t WalletImpl::defaultMixin() const
+
+ void WalletImpl::setDefaultMixin(uint32_t arg)
+ {
++ if (checkBackgroundSync("cannot set default mixin"))
++ return;
+ m_wallet->default_mixin(arg);
+ }
+
+ bool WalletImpl::setCacheAttribute(const std::string &key, const std::string &val)
+ {
++ if (checkBackgroundSync("cannot set cache attribute"))
++ return false;
+ m_wallet->set_attribute(key, val);
+ return true;
+ }
+@@ -1912,6 +2070,8 @@ std::string WalletImpl::getCacheAttribute(const std::string &key) const
+
+ bool WalletImpl::setUserNote(const std::string &txid, const std::string &note)
+ {
++ if (checkBackgroundSync("cannot set user note"))
++ return false;
+ cryptonote::blobdata txid_data;
+ if(!epee::string_tools::parse_hexstr_to_binbuff(txid, txid_data) || txid_data.size() != sizeof(crypto::hash))
+ return false;
+@@ -1923,6 +2083,8 @@ bool WalletImpl::setUserNote(const std::string &txid, const std::string &note)
+
+ std::string WalletImpl::getUserNote(const std::string &txid) const
+ {
++ if (checkBackgroundSync("cannot get user note"))
++ return "";
+ cryptonote::blobdata txid_data;
+ if(!epee::string_tools::parse_hexstr_to_binbuff(txid, txid_data) || txid_data.size() != sizeof(crypto::hash))
+ return "";
+@@ -1933,6 +2095,9 @@ std::string WalletImpl::getUserNote(const std::string &txid) const
+
+ std::string WalletImpl::getTxKey(const std::string &txid_str) const
+ {
++ if (checkBackgroundSync("cannot get tx key"))
++ return "";
++
+ crypto::hash txid;
+ if(!epee::string_tools::hex_to_pod(txid_str, txid))
+ {
+@@ -2017,6 +2182,9 @@ bool WalletImpl::checkTxKey(const std::string &txid_str, std::string tx_key_str,
+
+ std::string WalletImpl::getTxProof(const std::string &txid_str, const std::string &address_str, const std::string &message) const
+ {
++ if (checkBackgroundSync("cannot get tx proof"))
++ return "";
++
+ crypto::hash txid;
+ if (!epee::string_tools::hex_to_pod(txid_str, txid))
+ {
+@@ -2073,6 +2241,9 @@ bool WalletImpl::checkTxProof(const std::string &txid_str, const std::string &ad
+ }
+
+ std::string WalletImpl::getSpendProof(const std::string &txid_str, const std::string &message) const {
++ if (checkBackgroundSync("cannot get spend proof"))
++ return "";
++
+ crypto::hash txid;
+ if(!epee::string_tools::hex_to_pod(txid_str, txid))
+ {
+@@ -2115,6 +2286,9 @@ bool WalletImpl::checkSpendProof(const std::string &txid_str, const std::string
+ }
+
+ std::string WalletImpl::getReserveProof(bool all, uint32_t account_index, uint64_t amount, const std::string &message) const {
++ if (checkBackgroundSync("cannot get reserve proof"))
++ return "";
++
+ try
+ {
+ clearStatus();
+@@ -2161,6 +2335,9 @@ bool WalletImpl::checkReserveProof(const std::string &address, const std::string
+
+ std::string WalletImpl::signMessage(const std::string &message, const std::string &address)
+ {
++ if (checkBackgroundSync("cannot sign message"))
++ return "";
++
+ if (address.empty()) {
+ return m_wallet->sign(message, tools::wallet2::sign_with_spend_key);
+ }
+@@ -2288,6 +2465,16 @@ bool WalletImpl::isDeterministic() const
+ return m_wallet->is_deterministic();
+ }
+
++bool WalletImpl::isBackgroundSyncing() const
++{
++ return m_wallet->is_background_syncing();
++}
++
++bool WalletImpl::isBackgroundWallet() const
++{
++ return m_wallet->is_background_wallet();
++}
++
+ void WalletImpl::clearStatus() const
+ {
+ boost::lock_guard<boost::mutex> l(m_statusMutex);
+@@ -2356,9 +2543,7 @@ void WalletImpl::doRefresh()
+ if(rescan)
+ m_wallet->rescan_blockchain(false);
+ m_wallet->refresh(trustedDaemon());
+- if (!m_synchronized) {
+- m_synchronized = true;
+- }
++ m_synchronized = m_wallet->is_synced();
+ // assuming if we have empty history, it wasn't initialized yet
+ // for further history changes client need to update history in
+ // "on_money_received" and "on_money_sent" callbacks
+@@ -2462,6 +2647,24 @@ bool WalletImpl::doInit(const string &daemon_address, const std::string &proxy_a
+ return true;
+ }
+
++bool WalletImpl::checkBackgroundSync(const std::string &message) const
++{
++ clearStatus();
++ if (m_wallet->is_background_wallet())
++ {
++ LOG_ERROR("Background wallets " + message);
++ setStatusError(tr("Background wallets ") + message);
++ return true;
++ }
++ if (m_wallet->is_background_syncing())
++ {
++ LOG_ERROR(message + " while background syncing");
++ setStatusError(message + tr(" while background syncing. Stop background syncing first."));
++ return true;
++ }
++ return false;
++}
++
+ bool WalletImpl::parse_uri(const std::string &uri, std::string &address, std::string &payment_id, uint64_t &amount, std::string &tx_description, std::string &recipient_name, std::vector<std::string> &unknown_parameters, std::string &error)
+ {
+ return m_wallet->parse_uri(uri, address, payment_id, amount, tx_description, recipient_name, unknown_parameters, error);
+@@ -2480,6 +2683,8 @@ std::string WalletImpl::getDefaultDataDir() const
+ bool WalletImpl::rescanSpent()
+ {
+ clearStatus();
++ if (checkBackgroundSync("cannot rescan spent"))
++ return false;
+ if (!trustedDaemon()) {
+ setStatusError(tr("Rescan spent can only be used with a trusted daemon"));
+ return false;
+diff --git a/src/wallet/api/wallet.h b/src/wallet/api/wallet.h
+index 787215ab3..9acd2871f 100644
+--- a/src/wallet/api/wallet.h
++++ b/src/wallet/api/wallet.h
+@@ -181,6 +181,13 @@ public:
+ bool importOutputs(const std::string &filename) override;
+ bool scanTransactions(const std::vector<std::string> &txids) override;
+
++ bool setupBackgroundSync(const BackgroundSyncType background_sync_type, const std::string &wallet_password, const optional<std::string> &background_cache_password = optional<std::string>()) override;
++ BackgroundSyncType getBackgroundSyncType() const override;
++ bool startBackgroundSync() override;
++ bool stopBackgroundSync(const std::string &wallet_password) override;
++ bool isBackgroundSyncing() const override;
++ bool isBackgroundWallet() const override;
++
+ virtual void disposeTransaction(PendingTransaction * t) override;
+ virtual uint64_t estimateTransactionFee(const std::vector<std::pair<std::string, uint64_t>> &destinations,
+ PendingTransaction::Priority priority) const override;
+@@ -249,6 +256,7 @@ private:
+ bool isNewWallet() const;
+ void pendingTxPostProcess(PendingTransactionImpl * pending);
+ bool doInit(const std::string &daemon_address, const std::string &proxy_address, uint64_t upper_transaction_size_limit = 0, bool ssl = false);
++ bool checkBackgroundSync(const std::string &message) const;
+
+ private:
+ friend class PendingTransactionImpl;
+@@ -263,6 +271,10 @@ private:
+ mutable boost::mutex m_statusMutex;
+ mutable int m_status;
+ mutable std::string m_errorString;
++ // TODO: harden password handling in the wallet API, see relevant discussion
++ // https://github.com/monero-project/monero-gui/issues/1537
++ // https://github.com/feather-wallet/feather/issues/72#issuecomment-1405602142
++ // https://github.com/monero-project/monero/pull/8619#issuecomment-1632951461
+ std::string m_password;
+ std::unique_ptr<TransactionHistoryImpl> m_history;
+ std::unique_ptr<Wallet2CallbackImpl> m_wallet2Callback;
+diff --git a/src/wallet/api/wallet2_api.h b/src/wallet/api/wallet2_api.h
+index 9ea753083..4268b656e 100644
+--- a/src/wallet/api/wallet2_api.h
++++ b/src/wallet/api/wallet2_api.h
+@@ -445,6 +445,12 @@ struct Wallet
+ ConnectionStatus_WrongVersion
+ };
+
++ enum BackgroundSyncType {
++ BackgroundSync_Off = 0,
++ BackgroundSync_ReusePassword = 1,
++ BackgroundSync_CustomPassword = 2
++ };
++
+ virtual ~Wallet() = 0;
+ virtual std::string seed(const std::string& seed_offset = "") const = 0;
+ virtual std::string getSeedLanguage() const = 0;
+@@ -940,6 +946,42 @@ struct Wallet
+ */
+ virtual bool scanTransactions(const std::vector<std::string> &txids) = 0;
+
++ /*!
++ * \brief setupBackgroundSync - setup background sync mode with just a view key
++ * \param background_sync_type - the mode the wallet background syncs in
++ * \param wallet_password
++ * \param background_cache_password - custom password to encrypt background cache, only needed for custom password background sync type
++ * \return - true on success
++ */
++ virtual bool setupBackgroundSync(const BackgroundSyncType background_sync_type, const std::string &wallet_password, const optional<std::string> &background_cache_password) = 0;
++
++ /*!
++ * \brief getBackgroundSyncType - get mode the wallet background syncs in
++ * \return - the type, or off if type is unknown
++ */
++ virtual BackgroundSyncType getBackgroundSyncType() const = 0;
++
++ /**
++ * @brief startBackgroundSync - sync the chain in the background with just view key
++ */
++ virtual bool startBackgroundSync() = 0;
++
++ /**
++ * @brief stopBackgroundSync - bring back spend key and process background synced txs
++ * \param wallet_password
++ */
++ virtual bool stopBackgroundSync(const std::string &wallet_password) = 0;
++
++ /**
++ * @brief isBackgroundSyncing - returns true if the wallet is background syncing
++ */
++ virtual bool isBackgroundSyncing() const = 0;
++
++ /**
++ * @brief isBackgroundWallet - returns true if the wallet is a background wallet
++ */
++ virtual bool isBackgroundWallet() const = 0;
++
+ virtual TransactionHistory * history() = 0;
+ virtual AddressBook * addressBook() = 0;
+ virtual Subaddress * subaddress() = 0;
+diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
+index e4e02c782..618c43cee 100644
+--- a/src/wallet/wallet2.cpp
++++ b/src/wallet/wallet2.cpp
+@@ -1010,14 +1010,14 @@ uint64_t num_priv_multisig_keys_post_setup(uint64_t threshold, uint64_t total)
+ * @param keys_data_key the chacha key that encrypts wallet keys files
+ * @return crypto::chacha_key the chacha key that encrypts the wallet cache files
+ */
+-crypto::chacha_key derive_cache_key(const crypto::chacha_key& keys_data_key)
++crypto::chacha_key derive_cache_key(const crypto::chacha_key& keys_data_key, const unsigned char domain_separator)
+ {
+ static_assert(HASH_SIZE == sizeof(crypto::chacha_key), "Mismatched sizes of hash and chacha key");
+
+ crypto::chacha_key cache_key;
+ epee::mlocked<tools::scrubbed_arr<char, HASH_SIZE+1>> cache_key_data;
+ memcpy(cache_key_data.data(), &keys_data_key, HASH_SIZE);
+- cache_key_data[HASH_SIZE] = config::HASH_KEY_WALLET_CACHE;
++ cache_key_data[HASH_SIZE] = domain_separator;
+ cn_fast_hash(cache_key_data.data(), HASH_SIZE+1, (crypto::hash&) cache_key);
+
+ return cache_key;
+@@ -1105,7 +1105,7 @@ wallet_keys_unlocker::wallet_keys_unlocker(wallet2 &w, const boost::optional<too
+ boost::lock_guard<boost::mutex> lock(lockers_lock);
+ if (lockers++ > 0)
+ locked = false;
+- if (!locked || w.is_unattended() || w.ask_password() != tools::wallet2::AskPasswordToDecrypt || w.watch_only())
++ if (!locked || w.is_unattended() || w.ask_password() != tools::wallet2::AskPasswordToDecrypt || w.watch_only() || w.is_background_syncing())
+ {
+ locked = false;
+ return;
+@@ -1222,6 +1222,11 @@ wallet2::wallet2(network_type nettype, uint64_t kdf_rounds, bool unattended, std
+ m_ignore_outputs_above(MONEY_SUPPLY),
+ m_ignore_outputs_below(0),
+ m_track_uses(false),
++ m_is_background_wallet(false),
++ m_background_sync_type(BackgroundSyncOff),
++ m_background_syncing(false),
++ m_processing_background_cache(false),
++ m_custom_background_key(boost::none),
+ m_show_wallet_name_when_locked(false),
+ m_inactivity_lock_timeout(DEFAULT_INACTIVITY_LOCK_TIMEOUT),
+ m_setup_background_mining(BackgroundMiningMaybe),
+@@ -1877,6 +1882,9 @@ bool has_nonrequested_tx_at_height_or_above_requested(uint64_t height, const std
+ //----------------------------------------------------------------------------------------------------
+ void wallet2::scan_tx(const std::unordered_set<crypto::hash> &txids)
+ {
++ THROW_WALLET_EXCEPTION_IF(m_background_syncing || m_is_background_wallet, error::wallet_internal_error,
++ "cannot scan tx from background wallet");
++
+ // Get the transactions from daemon in batches sorted lowest height to highest
+ tx_entry_data txs_to_scan = get_tx_entries(txids);
+ if (txs_to_scan.tx_entries.empty())
+@@ -2184,11 +2192,11 @@ void wallet2::scan_output(const cryptonote::transaction &tx, bool miner_tx, cons
+ THROW_WALLET_EXCEPTION_IF(i >= tx.vout.size(), error::wallet_internal_error, "Invalid vout index");
+
+ // if keys are encrypted, ask for password
+- if (m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only && !m_multisig_rescan_k)
++ if (m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only && !m_multisig_rescan_k && !m_background_syncing)
+ {
+ static critical_section password_lock;
+ CRITICAL_REGION_LOCAL(password_lock);
+- if (!m_encrypt_keys_after_refresh)
++ if (!m_encrypt_keys_after_refresh && !m_processing_background_cache)
+ {
+ boost::optional<epee::wipeable_string> pwd = m_callback->on_get_password(pool ? "output found in pool" : "output received");
+ THROW_WALLET_EXCEPTION_IF(!pwd, error::password_needed, tr("Password is needed to compute key image for incoming monero"));
+@@ -2200,7 +2208,7 @@ void wallet2::scan_output(const cryptonote::transaction &tx, bool miner_tx, cons
+ crypto::public_key output_public_key;
+ THROW_WALLET_EXCEPTION_IF(!get_output_public_key(tx.vout[i], output_public_key), error::wallet_internal_error, "Failed to get output public key");
+
+- if (m_multisig)
++ if (m_multisig || m_background_syncing/*no spend key*/)
+ {
+ tx_scan_info.in_ephemeral.pub = output_public_key;
+ tx_scan_info.in_ephemeral.sec = crypto::null_skey;
+@@ -2457,6 +2465,14 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
+ THROW_WALLET_EXCEPTION_IF(tx.vout.size() != o_indices.size(), error::wallet_internal_error,
+ "transactions outputs size=" + std::to_string(tx.vout.size()) +
+ " not match with daemon response size=" + std::to_string(o_indices.size()));
++
++ // we're going to re-process this receive when background sync is disabled
++ if (m_background_syncing && m_background_sync_data.txs.find(txid) == m_background_sync_data.txs.end())
++ {
++ size_t bgs_idx = m_background_sync_data.txs.size();
++ LOG_PRINT_L2("Adding received tx " << txid << " to background sync data (idx=" << bgs_idx << ")");
++ m_background_sync_data.txs.insert({txid, background_synced_tx{bgs_idx, tx, o_indices, height, ts, double_spend_seen}});
++ }
+ }
+
+ for(size_t o: outs)
+@@ -2482,7 +2498,7 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
+ td.m_tx = (const cryptonote::transaction_prefix&)tx;
+ td.m_txid = txid;
+ td.m_key_image = tx_scan_info[o].ki;
+- td.m_key_image_known = !m_watch_only && !m_multisig;
++ td.m_key_image_known = !m_watch_only && !m_multisig && !m_background_syncing;
+ if (!td.m_key_image_known)
+ {
+ // we might have cold signed, and have a mapping to key images
+@@ -2672,10 +2688,17 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
+ set_spent(it->second, height);
+ if (!ignore_callbacks && 0 != m_callback)
+ m_callback->on_money_spent(height, txid, tx, amount, tx, td.m_subaddr_index);
++
++ if (m_background_syncing && m_background_sync_data.txs.find(txid) == m_background_sync_data.txs.end())
++ {
++ size_t bgs_idx = m_background_sync_data.txs.size();
++ LOG_PRINT_L2("Adding spent tx " << txid << " to background sync data (idx=" << bgs_idx << ")");
++ m_background_sync_data.txs.insert({txid, background_synced_tx{bgs_idx, tx, o_indices, height, ts, double_spend_seen}});
++ }
+ }
+ }
+
+- if (!pool && m_track_uses)
++ if (!pool && (m_track_uses || (m_background_syncing && it == m_key_images.end())))
+ {
+ PERF_TIMER(track_uses);
+ const uint64_t amount = in_to_key.amount;
+@@ -2689,7 +2712,19 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
+ {
+ size_t idx = i->second;
+ THROW_WALLET_EXCEPTION_IF(idx >= m_transfers.size(), error::wallet_internal_error, "Output tracker cache index out of range");
+- m_transfers[idx].m_uses.push_back(std::make_pair(height, txid));
++
++ if (m_track_uses)
++ m_transfers[idx].m_uses.push_back(std::make_pair(height, txid));
++
++ // We'll re-process all txs which *might* be spends when we disable
++ // background sync and retrieve the spend key. We don't know if an
++ // output is a spend in this tx if we don't know its key image.
++ if (m_background_syncing && !m_transfers[idx].m_key_image_known && m_background_sync_data.txs.find(txid) == m_background_sync_data.txs.end())
++ {
++ size_t bgs_idx = m_background_sync_data.txs.size();
++ LOG_PRINT_L2("Adding plausible spent tx " << txid << " to background sync data (idx=" << bgs_idx << ")");
++ m_background_sync_data.txs.insert({txid, background_synced_tx{bgs_idx, tx, o_indices, height, ts, double_spend_seen}});
++ }
+ }
+ }
+ }
+@@ -2699,7 +2734,16 @@ void wallet2::process_new_transaction(const crypto::hash &txid, const cryptonote
+ continue;
+ for (uint64_t offset: offsets)
+ if (offset == td.m_global_output_index)
+- td.m_uses.push_back(std::make_pair(height, txid));
++ {
++ if (m_track_uses)
++ td.m_uses.push_back(std::make_pair(height, txid));
++ if (m_background_syncing && !td.m_key_image_known && m_background_sync_data.txs.find(txid) == m_background_sync_data.txs.end())
++ {
++ size_t bgs_idx = m_background_sync_data.txs.size();
++ LOG_PRINT_L2("Adding plausible spent tx " << txid << " to background sync data (idx=" << bgs_idx << ")");
++ m_background_sync_data.txs.insert({txid, background_synced_tx{bgs_idx, tx, o_indices, height, ts, double_spend_seen}});
++ }
++ }
+ }
+ }
+ }
+@@ -3072,8 +3116,8 @@ void wallet2::pull_blocks(bool first, bool try_incremental, uint64_t start_heigh
+ req.start_height = start_height;
+ req.no_miner_tx = m_refresh_type == RefreshNoCoinbase;
+
+- req.requested_info = first ? COMMAND_RPC_GET_BLOCKS_FAST::BLOCKS_AND_POOL : COMMAND_RPC_GET_BLOCKS_FAST::BLOCKS_ONLY;
+- if (try_incremental)
++ req.requested_info = (first && !m_background_syncing) ? COMMAND_RPC_GET_BLOCKS_FAST::BLOCKS_AND_POOL : COMMAND_RPC_GET_BLOCKS_FAST::BLOCKS_ONLY;
++ if (try_incremental && !m_background_syncing)
+ req.pool_info_since = m_pool_info_query_time;
+
+ {
+@@ -3100,7 +3144,7 @@ void wallet2::pull_blocks(bool first, bool try_incremental, uint64_t start_heigh
+ << ", height " << blocks_start_height + blocks.size() << ", node height " << res.current_height
+ << ", pool info " << static_cast<unsigned int>(res.pool_info_extent));
+
+- if (first)
++ if (first && !m_background_syncing)
+ {
+ if (res.pool_info_extent != COMMAND_RPC_GET_BLOCKS_FAST::NONE)
+ {
+@@ -3612,6 +3656,9 @@ void wallet2::process_unconfirmed_transfer(bool incremental, const crypto::hash
+ // incremental update anymore, because with that we might miss some txs altogether.
+ void wallet2::update_pool_state(std::vector<std::tuple<cryptonote::transaction, crypto::hash, bool>> &process_txs, bool refreshed, bool try_incremental)
+ {
++ process_txs.clear();
++ if (m_background_syncing)
++ return;
+ bool updated = false;
+ if (m_pool_info_query_time != 0 && try_incremental)
+ {
+@@ -4182,6 +4229,8 @@ void wallet2::refresh(bool trusted_daemon, uint64_t start_height, uint64_t & blo
+ }
+
+ m_first_refresh_done = true;
++ if (m_background_syncing || m_is_background_wallet)
++ m_background_sync_data.first_refresh_done = true;
+
+ LOG_PRINT_L1("Refresh done, blocks received: " << blocks_fetched << ", balance (all accounts): " << print_money(balance_all(false)) << ", unlocked: " << print_money(unlocked_balance_all(false)));
+ }
+@@ -4267,6 +4316,14 @@ wallet2::detached_blockchain_data wallet2::detach_blockchain(uint64_t height, st
+ td.m_uses.pop_back();
+ }
+
++ for (auto it = m_background_sync_data.txs.begin(); it != m_background_sync_data.txs.end(); )
++ {
++ if(height <= it->second.height)
++ it = m_background_sync_data.txs.erase(it);
++ else
++ ++it;
++ }
++
+ if (output_tracker_cache)
+ output_tracker_cache->clear();
+
+@@ -4343,6 +4400,9 @@ void wallet2::handle_reorg(uint64_t height, std::map<std::pair<uint64_t, uint64_
+ error::wallet_internal_error, "Daemon claims reorg below last checkpoint");
+ detached_blockchain_data dbd = detach_blockchain(height, output_tracker_cache);
+
++ if (m_background_syncing && height < m_background_sync_data.start_height)
++ m_background_sync_data.start_height = height;
++
+ if (m_callback)
+ m_callback->on_reorg(height, dbd.detached_blockchain.size(), dbd.detached_tx_hashes.size());
+ }
+@@ -4352,6 +4412,7 @@ bool wallet2::deinit()
+ if(m_is_initialized) {
+ m_is_initialized = false;
+ unlock_keys_file();
++ unlock_background_keys_file();
+ m_account.deinit();
+ }
+ return true;
+@@ -4378,6 +4439,9 @@ bool wallet2::clear()
+ m_device_last_key_image_sync = 0;
+ m_pool_info_query_time = 0;
+ m_skip_to_height = 0;
++ m_background_sync_data.first_refresh_done = false;
++ m_background_sync_data.start_height = 0;
++ m_background_sync_data.txs.clear();
+ return true;
+ }
+ //----------------------------------------------------------------------------------------------------
+@@ -4396,13 +4460,32 @@ void wallet2::clear_soft(bool keep_key_images)
+ m_scanned_pool_txs[1].clear();
+ m_pool_info_query_time = 0;
+ m_skip_to_height = 0;
++ m_background_sync_data.first_refresh_done = false;
++ m_background_sync_data.start_height = 0;
++ m_background_sync_data.txs.clear();
+
+ cryptonote::block b;
+ generate_genesis(b);
+ m_blockchain.push_back(get_block_hash(b));
+ m_last_block_reward = cryptonote::get_outs_money_amount(b.miner_tx);
+ }
+-
++//----------------------------------------------------------------------------------------------------
++void wallet2::clear_user_data()
++{
++ for (auto i = m_confirmed_txs.begin(); i != m_confirmed_txs.end(); ++i)
++ i->second.m_dests.clear();
++ for (auto i = m_unconfirmed_txs.begin(); i != m_unconfirmed_txs.end(); ++i)
++ i->second.m_dests.clear();
++ for (auto i = m_transfers.begin(); i != m_transfers.end(); ++i)
++ i->m_frozen = false;
++ m_tx_keys.clear();
++ m_tx_notes.clear();
++ m_address_book.clear();
++ m_subaddress_labels.clear();
++ m_attributes.clear();
++ m_account_tags = std::pair<serializable_map<std::string, std::string>, std::vector<std::string>>();
++}
++//----------------------------------------------------------------------------------------------------
+ /*!
+ * \brief Stores wallet information to wallet file.
+ * \param keys_file_name Name of wallet file
+@@ -4414,16 +4497,35 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
+ {
+ boost::optional<wallet2::keys_file_data> keys_file_data = get_keys_file_data(password, watch_only);
+ CHECK_AND_ASSERT_MES(keys_file_data != boost::none, false, "failed to generate wallet keys data");
+-
++ return store_keys_file_data(keys_file_name, keys_file_data.get());
++}
++//----------------------------------------------------------------------------------------------------
++bool wallet2::store_keys(const std::string& keys_file_name, const crypto::chacha_key& key, bool watch_only, bool background_keys_file)
++{
++ boost::optional<wallet2::keys_file_data> keys_file_data = get_keys_file_data(key, watch_only, background_keys_file);
++ CHECK_AND_ASSERT_MES(keys_file_data != boost::none, false, "failed to generate wallet keys data");
++ return store_keys_file_data(keys_file_name, keys_file_data.get(), background_keys_file);
++}
++//----------------------------------------------------------------------------------------------------
++bool wallet2::store_keys_file_data(const std::string& keys_file_name, wallet2::keys_file_data &keys_file_data, bool background_keys_file)
++{
+ std::string tmp_file_name = keys_file_name + ".new";
+ std::string buf;
+- bool r = ::serialization::dump_binary(keys_file_data.get(), buf);
++ bool r = ::serialization::dump_binary(keys_file_data, buf);
+ r = r && save_to_file(tmp_file_name, buf);
+ CHECK_AND_ASSERT_MES(r, false, "failed to generate wallet keys file " << tmp_file_name);
+
+- unlock_keys_file();
++ if (!background_keys_file)
++ unlock_keys_file();
++ else
++ unlock_background_keys_file();
++
+ std::error_code e = tools::replace_file(tmp_file_name, keys_file_name);
+- lock_keys_file();
++
++ if (!background_keys_file)
++ lock_keys_file();
++ else
++ lock_background_keys_file(keys_file_name);
+
+ if (e) {
+ boost::filesystem::remove(tmp_file_name);
+@@ -4435,26 +4537,27 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
+ }
+ //----------------------------------------------------------------------------------------------------
+ boost::optional<wallet2::keys_file_data> wallet2::get_keys_file_data(const epee::wipeable_string& password, bool watch_only)
++{
++ crypto::chacha_key key;
++ crypto::generate_chacha_key(password.data(), password.size(), key, m_kdf_rounds);
++ verify_password_with_cached_key(key);
++ return get_keys_file_data(key, watch_only);
++}
++//----------------------------------------------------------------------------------------------------
++boost::optional<wallet2::keys_file_data> wallet2::get_keys_file_data(const crypto::chacha_key& key, bool watch_only, bool background_keys_file)
+ {
+ epee::byte_slice account_data;
+ std::string multisig_signers;
+ std::string multisig_derivations;
+ cryptonote::account_base account = m_account;
+
+- crypto::chacha_key key;
+- crypto::generate_chacha_key(password.data(), password.size(), key, m_kdf_rounds);
+-
+- // We use m_cache_key as a deterministic test to see if given key corresponds to original password
+- const crypto::chacha_key cache_key = derive_cache_key(key);
+- THROW_WALLET_EXCEPTION_IF(cache_key != m_cache_key, error::invalid_password);
+-
+ if (m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only)
+ {
+ account.encrypt_viewkey(key);
+ account.decrypt_keys(key);
+ }
+
+- if (watch_only)
++ if (watch_only || background_keys_file)
+ account.forget_spend_key();
+
+ account.encrypt_keys(key);
+@@ -4589,6 +4692,9 @@ boost::optional<wallet2::keys_file_data> wallet2::get_keys_file_data(const epee:
+ value2.SetInt(m_track_uses ? 1 : 0);
+ json.AddMember("track_uses", value2, json.GetAllocator());
+
++ value2.SetInt(m_background_sync_type);
++ json.AddMember("background_sync_type", value2, json.GetAllocator());
++
+ value2.SetInt(m_show_wallet_name_when_locked ? 1 : 0);
+ json.AddMember("show_wallet_name_when_locked", value2, json.GetAllocator());
+
+@@ -4646,6 +4752,13 @@ boost::optional<wallet2::keys_file_data> wallet2::get_keys_file_data(const epee:
+ value2.SetInt(m_enable_multisig ? 1 : 0);
+ json.AddMember("enable_multisig", value2, json.GetAllocator());
+
++ if (m_background_sync_type == BackgroundSyncCustomPassword && !background_keys_file && m_custom_background_key)
++ {
++ value.SetString(reinterpret_cast<const char*>(m_custom_background_key.get().data()), m_custom_background_key.get().size());
++ json.AddMember("custom_background_key", value, json.GetAllocator());
++ }
++
++
+ value2.SetInt(m_polyseed ? 1 : 0);
+ json.AddMember("polyseed", value2, json.GetAllocator());
+
+@@ -4675,13 +4788,81 @@ void wallet2::setup_keys(const epee::wipeable_string &password)
+ m_account.decrypt_viewkey(key);
+ }
+
+- m_cache_key = derive_cache_key(key);
++ m_cache_key = derive_cache_key(key, config::HASH_KEY_WALLET_CACHE);
+
+ get_ringdb_key();
+ }
+ //----------------------------------------------------------------------------------------------------
++void validate_background_cache_password_usage(const tools::wallet2::BackgroundSyncType background_sync_type, const boost::optional<epee::wipeable_string> &background_cache_password, const bool multisig, const bool watch_only, const bool key_on_device)
++{
++ THROW_WALLET_EXCEPTION_IF(multisig || watch_only || key_on_device, error::wallet_internal_error, multisig
++ ? "Background sync not implemented for multisig wallets" : watch_only
++ ? "Background sync not implemented for view only wallets"
++ : "Background sync not implemented for HW wallets");
++
++ switch (background_sync_type)
++ {
++ case tools::wallet2::BackgroundSyncOff:
++ {
++ THROW_WALLET_EXCEPTION(error::wallet_internal_error, "background sync is not enabled");
++ break;
++ }
++ case tools::wallet2::BackgroundSyncReusePassword:
++ {
++ THROW_WALLET_EXCEPTION_IF(background_cache_password, error::wallet_internal_error,
++ "unexpected custom background cache password");
++ break;
++ }
++ case tools::wallet2::BackgroundSyncCustomPassword:
++ {
++ THROW_WALLET_EXCEPTION_IF(!background_cache_password, error::wallet_internal_error,
++ "expected custom background cache password");
++ break;
++ }
++ default: THROW_WALLET_EXCEPTION(error::wallet_internal_error, "unknown background sync type");
++ }
++}
++//----------------------------------------------------------------------------------------------------
++void get_custom_background_key(const epee::wipeable_string &password, crypto::chacha_key &custom_background_key, const uint64_t kdf_rounds)
++{
++ crypto::chacha_key key;
++ crypto::generate_chacha_key(password.data(), password.size(), key, kdf_rounds);
++ custom_background_key = derive_cache_key(key, config::HASH_KEY_BACKGROUND_KEYS_FILE);
++}
++//----------------------------------------------------------------------------------------------------
++const crypto::chacha_key wallet2::get_cache_key()
++{
++ if (m_background_sync_type == BackgroundSyncCustomPassword && m_background_syncing)
++ {
++ THROW_WALLET_EXCEPTION_IF(!m_custom_background_key, error::wallet_internal_error, "Custom background key not set");
++ // Domain separate keys used to encrypt background keys file and cache
++ return derive_cache_key(m_custom_background_key.get(), config::HASH_KEY_BACKGROUND_CACHE);
++ }
++ else
++ {
++ return m_cache_key;
++ }
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::verify_password_with_cached_key(const epee::wipeable_string &password)
++{
++ crypto::chacha_key key;
++ crypto::generate_chacha_key(password.data(), password.size(), key, m_kdf_rounds);
++ verify_password_with_cached_key(key);
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::verify_password_with_cached_key(const crypto::chacha_key &key)
++{
++ // We use m_cache_key as a deterministic test to see if given key corresponds to original password
++ const crypto::chacha_key cache_key = derive_cache_key(key, config::HASH_KEY_WALLET_CACHE);
++ THROW_WALLET_EXCEPTION_IF(cache_key != m_cache_key, error::invalid_password);
++}
++//----------------------------------------------------------------------------------------------------
+ void wallet2::change_password(const std::string &filename, const epee::wipeable_string &original_password, const epee::wipeable_string &new_password)
+ {
++ THROW_WALLET_EXCEPTION_IF(m_background_syncing || m_is_background_wallet, error::wallet_internal_error,
++ "cannot change password from background wallet");
++
+ if (m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only)
+ decrypt_keys(original_password);
+ setup_keys(new_password);
+@@ -4740,8 +4921,24 @@ bool wallet2::load_keys_buf(const std::string& keys_buf, const epee::wipeable_st
+ std::string account_data;
+ account_data.resize(keys_file_data.account_data.size());
+ crypto::chacha20(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
+- if (json.Parse(account_data.c_str()).HasParseError() || !json.IsObject())
++ const bool try_v0_format = json.Parse(account_data.c_str()).HasParseError() || !json.IsObject();
++ if (try_v0_format)
+ crypto::chacha8(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
++
++ // Check if it's a background keys file if both of the above formats fail
++ {
++ m_is_background_wallet = false;
++ m_background_syncing = false;
++ cryptonote::account_base account_data_check;
++ if (try_v0_format && !epee::serialization::load_t_from_binary(account_data_check, account_data))
++ {
++ get_custom_background_key(password, key, m_kdf_rounds);
++ crypto::chacha20(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
++ m_is_background_wallet = !json.Parse(account_data.c_str()).HasParseError() && json.IsObject();
++ m_background_syncing = m_is_background_wallet; // start a background wallet background syncing
++ }
++ }
++
+ // The contents should be JSON if the wallet follows the new format.
+ if (json.Parse(account_data.c_str()).HasParseError())
+ {
+@@ -4779,6 +4976,7 @@ bool wallet2::load_keys_buf(const std::string& keys_buf, const epee::wipeable_st
+ m_ignore_outputs_above = MONEY_SUPPLY;
+ m_ignore_outputs_below = 0;
+ m_track_uses = false;
++ m_background_sync_type = BackgroundSyncOff;
+ m_show_wallet_name_when_locked = false;
+ m_inactivity_lock_timeout = DEFAULT_INACTIVITY_LOCK_TIMEOUT;
+ m_setup_background_mining = BackgroundMiningMaybe;
+@@ -4796,6 +4994,7 @@ bool wallet2::load_keys_buf(const std::string& keys_buf, const epee::wipeable_st
+ m_credits_target = 0;
+ m_enable_multisig = false;
+ m_allow_mismatched_daemon_version = false;
++ m_custom_background_key = boost::none;
+ m_polyseed = false;
+ }
+ else if(json.IsObject())
+@@ -5034,6 +5233,40 @@ bool wallet2::load_keys_buf(const std::string& keys_buf, const epee::wipeable_st
+ GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, enable_multisig, int, Int, false, false);
+ m_enable_multisig = field_enable_multisig;
+ GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, polyseed, int, Int, false, false);
++
++ GET_FIELD_FROM_JSON_RETURN_ON_ERROR(json, background_sync_type, BackgroundSyncType, Int, false, BackgroundSyncOff);
++ m_background_sync_type = field_background_sync_type;
++
++ // Load encryption key used to encrypt background cache
++ crypto::chacha_key custom_background_key;
++ m_custom_background_key = boost::none;
++ if (m_background_sync_type == BackgroundSyncCustomPassword && !m_is_background_wallet)
++ {
++ if (!json.HasMember("custom_background_key"))
++ {
++ LOG_ERROR("Field custom_background_key not found in JSON");
++ return false;
++ }
++ else if (!json["custom_background_key"].IsString())
++ {
++ LOG_ERROR("Field custom_background_key found in JSON, but not String");
++ return false;
++ }
++ else if (json["custom_background_key"].GetStringLength() != sizeof(crypto::chacha_key))
++ {
++ LOG_ERROR("Field custom_background_key found in JSON, but not correct length");
++ return false;
++ }
++ const char *field_custom_background_key = json["custom_background_key"].GetString();
++ memcpy(custom_background_key.data(), field_custom_background_key, sizeof(crypto::chacha_key));
++ m_custom_background_key = boost::optional<crypto::chacha_key>(custom_background_key);
++ LOG_PRINT_L1("Loaded custom background key derived from custom password");
++ }
++ else if (json.HasMember("custom_background_key"))
++ {
++ LOG_ERROR("Unexpected field custom_background_key found in JSON");
++ }
++
+ m_polyseed = field_polyseed;
+ }
+ else
+@@ -5098,12 +5331,17 @@ bool wallet2::load_keys_buf(const std::string& keys_buf, const epee::wipeable_st
+ const cryptonote::account_keys& keys = m_account.get_keys();
+ hw::device &hwdev = m_account.get_device();
+ r = r && hwdev.verify_keys(keys.m_view_secret_key, keys.m_account_address.m_view_public_key);
+- if (!m_watch_only && !m_multisig && hwdev.device_protocol() != hw::device::PROTOCOL_COLD)
++ if (!m_watch_only && !m_multisig && hwdev.device_protocol() != hw::device::PROTOCOL_COLD && !m_is_background_wallet)
+ r = r && hwdev.verify_keys(keys.m_spend_secret_key, keys.m_account_address.m_spend_public_key);
+ THROW_WALLET_EXCEPTION_IF(!r, error::wallet_files_doesnt_correspond, m_keys_file, m_wallet_file);
+
+ if (r)
+- setup_keys(password);
++ {
++ if (!m_is_background_wallet)
++ setup_keys(password);
++ else
++ m_custom_background_key = boost::optional<crypto::chacha_key>(key);
++ }
+
+ return true;
+ }
+@@ -5118,11 +5356,12 @@ bool wallet2::load_keys_buf(const std::string& keys_buf, const epee::wipeable_st
+ * can be used prior to rewriting wallet keys file, to ensure user has entered the correct password
+ *
+ */
+-bool wallet2::verify_password(const epee::wipeable_string& password)
++bool wallet2::verify_password(const epee::wipeable_string& password, crypto::secret_key &spend_key_out)
+ {
+ // this temporary unlocking is necessary for Windows (otherwise the file couldn't be loaded).
+ unlock_keys_file();
+- bool r = verify_password(m_keys_file, password, m_account.get_device().device_protocol() == hw::device::PROTOCOL_COLD || m_watch_only || m_multisig, m_account.get_device(), m_kdf_rounds);
++ const bool no_spend_key = m_account.get_device().device_protocol() == hw::device::PROTOCOL_COLD || m_watch_only || m_multisig || m_is_background_wallet;
++ bool r = verify_password(m_keys_file, password, no_spend_key, m_account.get_device(), m_kdf_rounds, spend_key_out);
+ lock_keys_file();
+ return r;
+ }
+@@ -5140,7 +5379,7 @@ bool wallet2::verify_password(const epee::wipeable_string& password)
+ * can be used prior to rewriting wallet keys file, to ensure user has entered the correct password
+ *
+ */
+-bool wallet2::verify_password(const std::string& keys_file_name, const epee::wipeable_string& password, bool no_spend_key, hw::device &hwdev, uint64_t kdf_rounds)
++bool wallet2::verify_password(const std::string& keys_file_name, const epee::wipeable_string& password, bool no_spend_key, hw::device &hwdev, uint64_t kdf_rounds, crypto::secret_key &spend_key_out)
+ {
+ rapidjson::Document json;
+ wallet2::keys_file_data keys_file_data;
+@@ -5157,9 +5396,22 @@ bool wallet2::verify_password(const std::string& keys_file_name, const epee::wip
+ std::string account_data;
+ account_data.resize(keys_file_data.account_data.size());
+ crypto::chacha20(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
+- if (json.Parse(account_data.c_str()).HasParseError() || !json.IsObject())
++ const bool try_v0_format = json.Parse(account_data.c_str()).HasParseError() || !json.IsObject();
++ if (try_v0_format)
+ crypto::chacha8(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
+
++ // Check if it's a background keys file if both of the above formats fail
++ {
++ cryptonote::account_base account_data_check;
++ if (try_v0_format && !epee::serialization::load_t_from_binary(account_data_check, account_data))
++ {
++ get_custom_background_key(password, key, kdf_rounds);
++ crypto::chacha20(keys_file_data.account_data.data(), keys_file_data.account_data.size(), key, keys_file_data.iv, &account_data[0]);
++ const bool is_background_wallet = json.Parse(account_data.c_str()).HasParseError() && json.IsObject();
++ no_spend_key = no_spend_key || is_background_wallet;
++ }
++ }
++
+ // The contents should be JSON if the wallet follows the new format.
+ if (json.Parse(account_data.c_str()).HasParseError())
+ {
+@@ -5184,6 +5436,7 @@ bool wallet2::verify_password(const std::string& keys_file_name, const epee::wip
+ r = r && hwdev.verify_keys(keys.m_view_secret_key, keys.m_account_address.m_view_public_key);
+ if(!no_spend_key)
+ r = r && hwdev.verify_keys(keys.m_spend_secret_key, keys.m_account_address.m_spend_public_key);
++ spend_key_out = (!no_spend_key && r) ? keys.m_spend_secret_key : crypto::null_skey;
+ return r;
+ }
+
+@@ -5195,9 +5448,7 @@ void wallet2::encrypt_keys(const crypto::chacha_key &key)
+
+ void wallet2::decrypt_keys(const crypto::chacha_key &key)
+ {
+- // We use m_cache_key as a deterministic test to see if given key corresponds to original password
+- const crypto::chacha_key cache_key = derive_cache_key(key);
+- THROW_WALLET_EXCEPTION_IF(cache_key != m_cache_key, error::invalid_password);
++ verify_password_with_cached_key(key);
+
+ m_account.encrypt_viewkey(key);
+ m_account.decrypt_keys(key);
+@@ -5915,11 +6166,30 @@ void wallet2::rewrite(const std::string& wallet_name, const epee::wipeable_strin
+ {
+ if (wallet_name.empty())
+ return;
++ THROW_WALLET_EXCEPTION_IF(m_background_syncing || m_is_background_wallet, error::wallet_internal_error,
++ "cannot change wallet settings from background wallet");
+ prepare_file_names(wallet_name);
+ boost::system::error_code ignored_ec;
+ THROW_WALLET_EXCEPTION_IF(!boost::filesystem::exists(m_keys_file, ignored_ec), error::file_not_found, m_keys_file);
+ bool r = store_keys(m_keys_file, password, m_watch_only);
+ THROW_WALLET_EXCEPTION_IF(!r, error::file_save_error, m_keys_file);
++
++ // Update the background keys file when we rewrite the main wallet keys file
++ if (m_background_sync_type == BackgroundSyncCustomPassword && m_custom_background_key)
++ {
++ const std::string background_keys_filename = make_background_keys_file_name(wallet_name);
++ if (!lock_background_keys_file(background_keys_filename))
++ {
++ LOG_ERROR("Background keys file " << background_keys_filename << " is opened by another wallet program and cannot be rewritten");
++ return; // not fatal, background keys file will just have different wallet settings
++ }
++ store_background_keys(m_custom_background_key.get());
++ store_background_cache(m_custom_background_key.get(), true/*do_reset_background_sync_data*/);
++ }
++ else if (m_background_sync_type == BackgroundSyncReusePassword)
++ {
++ reset_background_sync_data(m_background_sync_data);
++ }
+ }
+ /*!
+ * \brief Writes to a file named based on the normal wallet (doesn't generate key, assumes it's already there)
+@@ -5953,6 +6223,16 @@ bool wallet2::wallet_valid_path_format(const std::string& file_path)
+ return !file_path.empty();
+ }
+ //----------------------------------------------------------------------------------------------------
++std::string wallet2::make_background_wallet_file_name(const std::string &wallet_file)
++{
++ return wallet_file + config::BACKGROUND_WALLET_SUFFIX;
++}
++//----------------------------------------------------------------------------------------------------
++std::string wallet2::make_background_keys_file_name(const std::string &wallet_file)
++{
++ return make_background_wallet_file_name(wallet_file) + ".keys";
++}
++//----------------------------------------------------------------------------------------------------
+ bool wallet2::parse_long_payment_id(const std::string& payment_id_str, crypto::hash& payment_id)
+ {
+ cryptonote::blobdata payment_id_data;
+@@ -6188,10 +6468,135 @@ void wallet2::load(const std::string& wallet_, const epee::wipeable_string& pass
+ THROW_WALLET_EXCEPTION_IF(true, error::file_read_error, "failed to load keys from buffer");
+ }
+
+- wallet_keys_unlocker unlocker(*this, m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only, password);
++ wallet_keys_unlocker unlocker(*this, m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only && !m_is_background_wallet, password);
+
+ //keys loaded ok!
+ //try to load wallet cache. but even if we failed, it is not big problem
++ load_wallet_cache(use_fs, cache_buf);
++
++ if (!m_persistent_rpc_client_id)
++ set_rpc_client_secret_key(rct::rct2sk(rct::skGen()));
++
++ cryptonote::block genesis;
++ generate_genesis(genesis);
++ crypto::hash genesis_hash = get_block_hash(genesis);
++
++ if (m_blockchain.empty())
++ {
++ m_blockchain.push_back(genesis_hash);
++ m_last_block_reward = cryptonote::get_outs_money_amount(genesis.miner_tx);
++ }
++ else
++ {
++ check_genesis(genesis_hash);
++ }
++
++ trim_hashchain();
++
++ if (get_num_subaddress_accounts() == 0)
++ add_subaddress_account(tr("Primary account"));
++
++ try
++ {
++ find_and_save_rings(false);
++ }
++ catch (const std::exception &e)
++ {
++ MERROR("Failed to save rings, will try again next time");
++ }
++
++ try
++ {
++ if (use_fs)
++ m_message_store.read_from_file(get_multisig_wallet_state(), m_mms_file, m_load_deprecated_formats);
++ }
++ catch (const std::exception &e)
++ {
++ MERROR("Failed to initialize MMS, it will be unusable");
++ }
++
++ try
++ {
++ if (use_fs)
++ process_background_cache_on_open();
++ }
++ catch (const std::exception &e)
++ {
++ MERROR("Failed to process background cache on open: " << e.what());
++ }
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::process_background_cache_on_open()
++{
++ if (m_wallet_file.empty())
++ return;
++ if (m_background_syncing || m_is_background_wallet)
++ return;
++ if (m_background_sync_type == BackgroundSyncOff)
++ return;
++ if (m_background_sync_type == BackgroundSyncReusePassword)
++ {
++ const background_sync_data_t background_sync_data = m_background_sync_data;
++ const hashchain blockchain = m_blockchain;
++ process_background_cache(background_sync_data, blockchain, m_last_block_reward);
++
++ // Reset the background cache after processing
++ reset_background_sync_data(m_background_sync_data);
++ }
++ else if (m_background_sync_type == BackgroundSyncCustomPassword)
++ {
++ // If the background wallet files don't exist, recreate them
++ const std::string background_keys_file = make_background_keys_file_name(m_wallet_file);
++ const std::string background_wallet_file = make_background_wallet_file_name(m_wallet_file);
++ const bool background_keys_file_exists = boost::filesystem::exists(background_keys_file);
++ const bool background_wallet_exists = boost::filesystem::exists(background_wallet_file);
++
++ THROW_WALLET_EXCEPTION_IF(!lock_background_keys_file(background_keys_file), error::background_wallet_already_open, background_wallet_file);
++ THROW_WALLET_EXCEPTION_IF(!m_custom_background_key, error::wallet_internal_error, "Custom background key not set");
++
++ if (!background_keys_file_exists)
++ {
++ MDEBUG("Background keys file not found, restoring");
++ store_background_keys(m_custom_background_key.get());
++ }
++
++ if (!background_wallet_exists)
++ {
++ MDEBUG("Background cache not found, restoring");
++ store_background_cache(m_custom_background_key.get(), true/*do_reset_background_sync_data*/);
++ return;
++ }
++
++ MDEBUG("Loading background cache");
++
++ // Set up a minimal background wallet2 instance
++ std::unique_ptr<wallet2> background_w2(new wallet2(m_nettype));
++ background_w2->m_is_background_wallet = true;
++ background_w2->m_background_syncing = true;
++ background_w2->m_background_sync_type = m_background_sync_type;
++ background_w2->m_custom_background_key = m_custom_background_key;
++
++ cryptonote::account_base account = m_account;
++ account.forget_spend_key();
++ background_w2->m_account = account;
++
++ // Load background cache from file
++ background_w2->clear();
++ background_w2->prepare_file_names(background_wallet_file);
++ background_w2->load_wallet_cache(true/*use_fs*/);
++
++ process_background_cache(background_w2->m_background_sync_data, background_w2->m_blockchain, background_w2->m_last_block_reward);
++
++ // Reset the background cache after processing
++ store_background_cache(m_custom_background_key.get(), true/*do_reset_background_sync_data*/);
++ } else {
++ THROW_WALLET_EXCEPTION(error::wallet_internal_error, "unknown background sync type");
++ }
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::load_wallet_cache(const bool use_fs, const std::string& cache_buf)
++{
++ boost::system::error_code e;
+ bool cache_missing = use_fs ? (!boost::filesystem::exists(m_wallet_file, e) || e) : cache_buf.empty();
+ if (cache_missing)
+ {
+@@ -6205,7 +6610,7 @@ void wallet2::load(const std::string& wallet_, const epee::wipeable_string& pass
+ bool r = true;
+ if (use_fs)
+ {
+- load_from_file(m_wallet_file, cache_file_buf, std::numeric_limits<size_t>::max());
++ r = load_from_file(m_wallet_file, cache_file_buf, std::numeric_limits<size_t>::max());
+ THROW_WALLET_EXCEPTION_IF(!r, error::file_read_error, m_wallet_file);
+ }
+
+@@ -6218,7 +6623,7 @@ void wallet2::load(const std::string& wallet_, const epee::wipeable_string& pass
+ THROW_WALLET_EXCEPTION_IF(!r, error::wallet_internal_error, "internal error: failed to deserialize \"" + m_wallet_file + '\"');
+ std::string cache_data;
+ cache_data.resize(cache_file_data.cache_data.size());
+- crypto::chacha20(cache_file_data.cache_data.data(), cache_file_data.cache_data.size(), m_cache_key, cache_file_data.iv, &cache_data[0]);
++ crypto::chacha20(cache_file_data.cache_data.data(), cache_file_data.cache_data.size(), get_cache_key(), cache_file_data.iv, &cache_data[0]);
+
+ try {
+ bool loaded = false;
+@@ -6459,6 +6864,21 @@ void wallet2::store_to(const std::string &path, const epee::wipeable_string &pas
+ }
+ }
+ }
++ else if (m_background_sync_type == BackgroundSyncCustomPassword && m_background_syncing && !m_is_background_wallet)
++ {
++ // We're background syncing, so store the wallet cache as a background cache
++ // keeping the background sync data
++ try
++ {
++ THROW_WALLET_EXCEPTION_IF(!m_custom_background_key, error::wallet_internal_error, "Custom background key not set");
++ store_background_cache(m_custom_background_key.get(), false/*do_reset_background_sync_data*/);
++ }
++ catch (const std::exception &e)
++ {
++ MERROR("Failed to store background cache while background syncing: " << e.what());
++ }
++ return;
++ }
+
+ // get wallet cache data
+ boost::optional<wallet2::cache_file_data> cache_file_data = get_cache_file_data();
+@@ -6552,6 +6972,22 @@ void wallet2::store_to(const std::string &path, const epee::wipeable_string &pas
+ // store should only exist if the MMS is really active
+ m_message_store.write_to_file(get_multisig_wallet_state(), m_mms_file);
+ }
++
++ if (m_background_sync_type == BackgroundSyncCustomPassword && !m_background_syncing && !m_is_background_wallet)
++ {
++ // Update the background wallet cache when we store the main wallet cache
++ // Note: if background syncing when this is called, it means the background
++ // wallet is open and was already stored above
++ try
++ {
++ THROW_WALLET_EXCEPTION_IF(!m_custom_background_key, error::wallet_internal_error, "Custom background key not set");
++ store_background_cache(m_custom_background_key.get(), true/*do_reset_background_sync_data*/);
++ }
++ catch (const std::exception &e)
++ {
++ MERROR("Failed to update background cache: " << e.what());
++ }
++ }
+ }
+ //----------------------------------------------------------------------------------------------------
+ boost::optional<wallet2::cache_file_data> wallet2::get_cache_file_data()
+@@ -6569,7 +7005,7 @@ boost::optional<wallet2::cache_file_data> wallet2::get_cache_file_data()
+ std::string cipher;
+ cipher.resize(cache_file_data.get().cache_data.size());
+ cache_file_data.get().iv = crypto::rand<crypto::chacha_iv>();
+- crypto::chacha20(cache_file_data.get().cache_data.data(), cache_file_data.get().cache_data.size(), m_cache_key, cache_file_data.get().iv, &cipher[0]);
++ crypto::chacha20(cache_file_data.get().cache_data.data(), cache_file_data.get().cache_data.size(), get_cache_key(), cache_file_data.get().iv, &cipher[0]);
+ cache_file_data.get().cache_data = cipher;
+ return cache_file_data;
+ }
+@@ -8645,6 +9081,34 @@ bool wallet2::is_keys_file_locked() const
+ return m_keys_file_locker->locked();
+ }
+
++bool wallet2::lock_background_keys_file(const std::string &background_keys_file)
++{
++ if (background_keys_file.empty() || !boost::filesystem::exists(background_keys_file))
++ return true;
++ if (m_background_keys_file_locker && m_background_keys_file_locker->locked())
++ return true;
++ m_background_keys_file_locker.reset(new tools::file_locker(background_keys_file));
++ return m_background_keys_file_locker->locked();
++}
++
++bool wallet2::unlock_background_keys_file()
++{
++ if (!m_background_keys_file_locker)
++ {
++ MDEBUG("background keys file locker is not set");
++ return false;
++ }
++ m_background_keys_file_locker.reset();
++ return true;
++}
++
++bool wallet2::is_background_keys_file_locked() const
++{
++ if (!m_background_keys_file_locker)
++ return false;
++ return m_background_keys_file_locker->locked();
++}
++
+ bool wallet2::tx_add_fake_output(std::vector<std::vector<tools::wallet2::get_outs_entry>> &outs, uint64_t global_index, const crypto::public_key& output_public_key, const rct::key& mask, uint64_t real_index, bool unlocked, std::unordered_set<crypto::public_key> &valid_public_keys_cache) const
+ {
+ if (!unlocked) // don't add locked outs
+@@ -13980,6 +14444,408 @@ bool wallet2::import_key_images(signed_tx_set & signed_tx, size_t offset, bool o
+ return import_key_images(signed_tx.key_images, offset, only_selected_transfers ? boost::make_optional(selected_transfers) : boost::none);
+ }
+
++/*
++ In background sync mode, we use just the view key when the wallet is scanning
++ to identify all txs where:
++
++ 1. We received an output.
++ 2. We spent an output.
++ 3. We *may* have spent a received output but we didn't know for sure because
++ the spend key was not loaded while background sync was enabled.
++
++ When the user is ready to use the spend key again, we call this function to
++ process all those background synced transactions with the spend key loaded,
++ so that we can properly generate key images for the transactions which we
++ we were not able to do so for while background sync was enabled. This allows
++ us to determine *all* receives and spends the user completed while the wallet
++ had background sync enabled. Once this function completes, we can continue
++ scanning from where the background sync left off.
++
++ Txs of type 3 (txs which we *may* have spent received output(s)) are txs where
++ 1+ rings contain an output that the user received and the wallet does not know
++ the associated key image for that output. We don't know if the user spent in
++ this type of tx or not. This function will generate key images for all outputs
++ we don't know key images for, and then check if those outputs were spent in
++ the txs of type 3.
++
++ By storing this type of "plausible spend tx" when scanning in background sync
++ mode, we avoid the need to query the daemon with key images when background
++ sync mode is disabled to see if those key images were spent. This would
++ reveal key images to 3rd party nodes for users who don't run their own.
++ Although this is not a perfect solution to avoid revealing key images to a 3rd
++ party node (since tx submission trivially reveals key images to a node), it's
++ probably better than revealing *unused* key images to a 3rd party node, which
++ would enable the 3rd party to deduce that a tx is spending an output at least
++ X old when the key image is included in the chain.
++*/
++void wallet2::process_background_cache(const background_sync_data_t &background_sync_data, const hashchain &background_synced_chain, uint64_t last_block_reward)
++{
++ // We expect the spend key to be in a decrypted state while
++ // m_processing_background_cache is true
++ m_processing_background_cache = true;
++ auto done_processing = epee::misc_utils::create_scope_leave_handler([&, this]() {
++ m_processing_background_cache = false;
++ });
++
++ if (m_background_syncing || m_multisig || m_watch_only || key_on_device())
++ return;
++
++ if (!background_sync_data.first_refresh_done)
++ {
++ MDEBUG("Skipping processing background cache, background cache has not synced yet");
++ return;
++ }
++
++ // Skip processing if wallet cache is synced higher than background cache
++ const uint64_t current_height = m_blockchain.size();
++ const uint64_t background_height = background_synced_chain.size();
++ MDEBUG("Background cache height " << background_height << " , wallet height " << current_height);
++ if (current_height > background_height)
++ {
++ MWARNING("Skipping processing background cache, synced height is higher than background cache");
++ return;
++ }
++
++ if (m_refresh_from_block_height < background_sync_data.wallet_refresh_from_block_height ||
++ m_subaddress_lookahead_major > background_sync_data.subaddress_lookahead_major ||
++ m_subaddress_lookahead_minor > background_sync_data.subaddress_lookahead_minor ||
++ m_refresh_type < background_sync_data.wallet_refresh_type)
++ {
++ MWARNING("Skipping processing background cache, background wallet sync settings did not match main wallet's");
++ MDEBUG("Wallet settings: " <<
++ ", m_refresh_from_block_height: " << m_refresh_from_block_height << " vs " << background_sync_data.wallet_refresh_from_block_height <<
++ ", m_subaddress_lookahead_major: " << m_subaddress_lookahead_major << " vs " << background_sync_data.subaddress_lookahead_major <<
++ ", m_subaddress_lookahead_minor: " << m_subaddress_lookahead_minor << " vs " << background_sync_data.subaddress_lookahead_minor <<
++ ", m_refresh_type: " << m_refresh_type << " vs " << background_sync_data.wallet_refresh_type);
++ return;
++ }
++
++ // Sort background synced txs in the order they appeared in the cache so that
++ // we process them in the order they appeared in the chain. Thus if tx2 spends
++ // from tx1, we will know because tx1 is processed before tx2.
++ std::vector<std::pair<crypto::hash, background_synced_tx>> sorted_bgs_cache(background_sync_data.txs.begin(), background_sync_data.txs.end());
++ std::sort(sorted_bgs_cache.begin(), sorted_bgs_cache.end(),
++ [](const std::pair<crypto::hash, background_synced_tx>& l, const std::pair<crypto::hash, background_synced_tx>& r)
++ {
++ uint64_t left_index = l.second.index_in_background_sync_data;
++ uint64_t right_index = r.second.index_in_background_sync_data;
++ THROW_WALLET_EXCEPTION_IF(
++ (left_index < right_index && l.second.height > r.second.height) ||
++ (left_index > right_index && l.second.height < r.second.height),
++ error::wallet_internal_error, "Unexpected background sync data order");
++ return left_index < right_index;
++ });
++
++ // All txs in the background cache should have height >= sync start height,
++ // but not fatal if not
++ if (!sorted_bgs_cache.empty() && sorted_bgs_cache[0].second.height < background_sync_data.start_height)
++ MWARNING("First tx in background cache has height (" << sorted_bgs_cache[0].second.height << ") lower than sync start height (" << background_sync_data.start_height << ")");
++
++ // We want to process all background synced txs in order to make sure
++ // the wallet state updates correctly. First we remove all txs from the wallet
++ // from before the background sync start height, then re-process them in
++ // chronological order. The background cache should contain a superset of
++ // *all* the wallet's txs from after the background sync start height.
++ MDEBUG("Processing " << background_sync_data.txs.size() << " background synced txs starting from height " << background_sync_data.start_height);
++ detached_blockchain_data dbd = detach_blockchain(background_sync_data.start_height);
++
++ for (const auto &bgs_tx : sorted_bgs_cache)
++ {
++ MDEBUG("Processing background synced tx " << bgs_tx.first);
++
++ process_new_transaction(bgs_tx.first, bgs_tx.second.tx, bgs_tx.second.output_indices, bgs_tx.second.height, 0, bgs_tx.second.block_timestamp,
++ cryptonote::is_coinbase(bgs_tx.second.tx), false/*pool*/, bgs_tx.second.double_spend_seen, {}, {}, true/*ignore_callbacks*/);
++
++ // Re-set destination addresses if they were previously set
++ if (m_confirmed_txs.find(bgs_tx.first) != m_confirmed_txs.end() &&
++ dbd.detached_confirmed_txs_dests.find(bgs_tx.first) != dbd.detached_confirmed_txs_dests.end())
++ {
++ m_confirmed_txs[bgs_tx.first].m_dests = std::move(dbd.detached_confirmed_txs_dests[bgs_tx.first]);
++ }
++ }
++
++ m_blockchain = background_synced_chain;
++ m_last_block_reward = last_block_reward;
++
++ MDEBUG("Finished processing background sync data");
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::reset_background_sync_data(background_sync_data_t &background_sync_data)
++{
++ background_sync_data.first_refresh_done = false;
++ background_sync_data.start_height = get_blockchain_current_height();
++ background_sync_data.txs.clear();
++
++ background_sync_data.wallet_refresh_from_block_height = m_refresh_from_block_height;
++ background_sync_data.subaddress_lookahead_major = m_subaddress_lookahead_major;
++ background_sync_data.subaddress_lookahead_minor = m_subaddress_lookahead_minor;
++ background_sync_data.wallet_refresh_type = m_refresh_type;
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::store_background_cache(const crypto::chacha_key &custom_background_key, const bool do_reset_background_sync_data)
++{
++ MDEBUG("Storing background cache (do_reset_background_sync_data=" << do_reset_background_sync_data << ")");
++
++ THROW_WALLET_EXCEPTION_IF(m_background_sync_type != BackgroundSyncCustomPassword, error::wallet_internal_error,
++ "Can only write a background cache when using a custom background password");
++
++ std::unique_ptr<wallet2> background_w2(new wallet2(m_nettype));
++ background_w2->prepare_file_names(make_background_wallet_file_name(m_wallet_file));
++
++ // Make sure background wallet is opened by this wallet
++ THROW_WALLET_EXCEPTION_IF(!lock_background_keys_file(background_w2->m_keys_file),
++ error::background_wallet_already_open, background_w2->m_wallet_file);
++
++ // Load a background wallet2 instance using this wallet2 instance
++ std::string this_wallet2;
++ bool r = ::serialization::dump_binary(*this, this_wallet2);
++ THROW_WALLET_EXCEPTION_IF(!r, error::wallet_internal_error, "Failed to serialize wallet cache");
++
++ background_w2->clear();
++ r = ::serialization::parse_binary(this_wallet2, *background_w2);
++ THROW_WALLET_EXCEPTION_IF(!r, error::wallet_internal_error, "Failed to deserialize wallet cache");
++
++ // Clear sensitive data from background cache not needed to sync
++ background_w2->clear_user_data();
++
++ background_w2->m_is_background_wallet = true;
++ if (do_reset_background_sync_data)
++ reset_background_sync_data(background_w2->m_background_sync_data);
++ else
++ background_w2->m_background_sync_data = m_background_sync_data;
++ background_w2->m_background_syncing = true;
++
++ background_w2->m_custom_background_key = boost::optional<crypto::chacha_key>(custom_background_key);
++ background_w2->m_background_sync_type = m_background_sync_type;
++ background_w2->store();
++
++ MDEBUG("Background cache stored (" << background_w2->m_transfers.size() << " transfers, " << background_w2->m_background_sync_data.txs.size() << " background synced txs)");
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::store_background_keys(const crypto::chacha_key &custom_background_key)
++{
++ MDEBUG("Storing background keys");
++
++ const std::string background_keys_file = make_background_keys_file_name(m_wallet_file);
++ bool r = store_keys(background_keys_file, custom_background_key, false/*watch_only*/, true/*background_keys_file*/);
++ THROW_WALLET_EXCEPTION_IF(!r, error::file_save_error, background_keys_file);
++ THROW_WALLET_EXCEPTION_IF(!is_background_keys_file_locked(), error::wallet_internal_error, background_keys_file + "\" should be locked");
++
++ // GUI uses the address file to differentiate non-mainnet wallets in the UI
++ const std::string background_address_file = make_background_wallet_file_name(m_wallet_file) + ".address.txt";
++ if (m_nettype != MAINNET && !boost::filesystem::exists(background_address_file))
++ {
++ r = save_to_file(background_address_file, m_account.get_public_address_str(m_nettype), true);
++ if (!r) MERROR("String with address text not saved");
++ }
++
++ MDEBUG("Background keys stored");
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::write_background_sync_wallet(const epee::wipeable_string &wallet_password, const epee::wipeable_string &background_cache_password)
++{
++ MDEBUG("Storing background sync wallet");
++ THROW_WALLET_EXCEPTION_IF(m_background_sync_type != BackgroundSyncCustomPassword, error::wallet_internal_error,
++ "Can only write a background sync wallet when using a custom background password");
++ THROW_WALLET_EXCEPTION_IF(m_background_syncing || m_is_background_wallet, error::wallet_internal_error,
++ "Can't write background sync wallet from an existing background cache");
++ THROW_WALLET_EXCEPTION_IF(wallet_password == background_cache_password,
++ error::background_custom_password_same_as_wallet_password);
++
++ // Set the background encryption key
++ crypto::chacha_key custom_background_key;
++ get_custom_background_key(background_cache_password, custom_background_key, m_kdf_rounds);
++
++ // Keep the background encryption key in memory so the main wallet can update
++ // the background cache when it stores the main wallet cache
++ m_custom_background_key = boost::optional<crypto::chacha_key>(custom_background_key);
++
++ if (m_wallet_file.empty() || m_keys_file.empty())
++ return;
++
++ // Save background keys file, then background cache, then update main wallet settings
++ store_background_keys(custom_background_key);
++ store_background_cache(custom_background_key, true/*do_reset_background_sync_data*/);
++ bool r = store_keys(m_keys_file, wallet_password, false/*watch_only*/);
++ THROW_WALLET_EXCEPTION_IF(!r, error::file_save_error, m_keys_file);
++
++ MDEBUG("Background sync wallet saved successfully");
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::setup_background_sync(BackgroundSyncType background_sync_type, const epee::wipeable_string &wallet_password, const boost::optional<epee::wipeable_string> &background_cache_password)
++{
++ MDEBUG("Setting background sync to type " << background_sync_type);
++ THROW_WALLET_EXCEPTION_IF(m_background_syncing || m_is_background_wallet, error::wallet_internal_error,
++ "Can't set background sync type from an existing background cache");
++ verify_password_with_cached_key(wallet_password);
++
++ if (background_sync_type != BackgroundSyncOff)
++ validate_background_cache_password_usage(background_sync_type, background_cache_password, m_multisig, m_watch_only, key_on_device());
++
++ THROW_WALLET_EXCEPTION_IF(background_sync_type == BackgroundSyncCustomPassword && wallet_password == background_cache_password,
++ error::background_custom_password_same_as_wallet_password);
++
++ if (m_background_sync_type == background_sync_type && background_sync_type != BackgroundSyncCustomPassword)
++ return; // No need to make any changes
++
++ if (!m_wallet_file.empty())
++ {
++ // Delete existing background files if they already exist
++ const std::string old_background_wallet_file = make_background_wallet_file_name(m_wallet_file);
++ const std::string old_background_keys_file = make_background_keys_file_name(m_wallet_file);
++ const std::string old_background_address_file = old_background_wallet_file + ".address.txt";
++
++ // Make sure no other program is using the background wallet
++ THROW_WALLET_EXCEPTION_IF(!lock_background_keys_file(old_background_keys_file),
++ error::background_wallet_already_open, old_background_wallet_file);
++
++ if (boost::filesystem::exists(old_background_wallet_file))
++ if (!boost::filesystem::remove(old_background_wallet_file))
++ LOG_ERROR("Error deleting background wallet file: " << old_background_wallet_file);
++
++ if (boost::filesystem::exists(old_background_keys_file))
++ if (!boost::filesystem::remove(old_background_keys_file))
++ LOG_ERROR("Error deleting background keys file: " << old_background_keys_file);
++
++ if (boost::filesystem::exists(old_background_address_file))
++ if (!boost::filesystem::remove(old_background_address_file))
++ LOG_ERROR("Error deleting background address file: " << old_background_address_file);
++ }
++
++ m_background_sync_type = background_sync_type;
++ m_custom_background_key = boost::none;
++
++ // Write the new files
++ switch (background_sync_type)
++ {
++ case BackgroundSyncOff:
++ case BackgroundSyncReusePassword: rewrite(m_wallet_file, wallet_password); break;
++ case BackgroundSyncCustomPassword: write_background_sync_wallet(wallet_password, background_cache_password.get()); break;
++ default: THROW_WALLET_EXCEPTION(error::wallet_internal_error, "unknown background sync type");
++ }
++
++ MDEBUG("Done setting background sync type");
++}
++//----------------------------------------------------------------------------------------------------
++/*
++ When background syncing, the wallet scans using just the view key, without
++ keeping the spend key in decrypted state. When a user returns to the wallet
++ and decrypts the spend key, the wallet processes the background synced txs,
++ then the wallet picks up scanning normally right where the background sync
++ left off.
++*/
++void wallet2::start_background_sync()
++{
++ THROW_WALLET_EXCEPTION_IF(m_background_sync_type == BackgroundSyncOff, error::wallet_internal_error,
++ "must setup background sync first before using background sync");
++ THROW_WALLET_EXCEPTION_IF(m_is_background_wallet, error::wallet_internal_error,
++ "Can't start background syncing from a background wallet (it is always background syncing)");
++
++ MDEBUG("Starting background sync");
++
++ if (m_background_syncing)
++ {
++ MDEBUG("Already background syncing");
++ return;
++ }
++
++ if (m_background_sync_type == BackgroundSyncCustomPassword && !m_wallet_file.empty())
++ {
++ // Save the current state of the wallet cache. Only necessary when using a
++ // custom background password which uses distinct background wallet to sync.
++ // When reusing wallet password to sync we reuse the main wallet cache.
++ store();
++
++ // Wipe user data from the background wallet cache not needed to sync.
++ // Only wipe user data from background cache if wallet cache is stored
++ // on disk; otherwise we could lose the data.
++ clear_user_data();
++
++ // Wipe m_cache_key since it can be used to decrypt main wallet cache
++ m_cache_key.scrub();
++ }
++
++ reset_background_sync_data(m_background_sync_data);
++ m_background_syncing = true;
++
++ // Wipe the spend key from memory
++ m_account.forget_spend_key();
++
++ MDEBUG("Background sync started at height " << m_background_sync_data.start_height);
++}
++//----------------------------------------------------------------------------------------------------
++void wallet2::stop_background_sync(const epee::wipeable_string &wallet_password, const crypto::secret_key &spend_secret_key)
++{
++ MDEBUG("Stopping background sync");
++
++ // Verify provided password and spend secret key. If no spend secret key is
++ // provided, recover it from the wallet keys file
++ crypto::secret_key recovered_spend_key = crypto::null_skey;
++ if (!m_wallet_file.empty())
++ {
++ THROW_WALLET_EXCEPTION_IF(!verify_password(wallet_password, recovered_spend_key), error::invalid_password);
++ }
++ else
++ {
++ verify_password_with_cached_key(wallet_password);
++ }
++
++ if (spend_secret_key != crypto::null_skey)
++ {
++ THROW_WALLET_EXCEPTION_IF(!m_wallet_file.empty() && spend_secret_key != recovered_spend_key,
++ error::invalid_spend_key);
++ MDEBUG("Setting spend secret key with the provided key");
++ recovered_spend_key = spend_secret_key;
++ }
++
++ // Verify private spend key derives to wallet's public spend key
++ const auto verify_spend_key = [this](crypto::secret_key &recovered_spend_key) -> bool
++ {
++ crypto::public_key spend_public_key;
++ return recovered_spend_key != crypto::null_skey &&
++ crypto::secret_key_to_public_key(recovered_spend_key, spend_public_key) &&
++ m_account.get_keys().m_account_address.m_spend_public_key == spend_public_key;
++ };
++ THROW_WALLET_EXCEPTION_IF(!verify_spend_key(recovered_spend_key), error::invalid_spend_key);
++
++ THROW_WALLET_EXCEPTION_IF(m_background_sync_type == BackgroundSyncOff, error::wallet_internal_error,
++ "must setup background sync first before using background sync");
++ THROW_WALLET_EXCEPTION_IF(m_is_background_wallet, error::wallet_internal_error,
++ "Can't stop background syncing from a background wallet");
++
++ if (!m_background_syncing)
++ return;
++
++ // Copy background cache, we're about to overwrite it
++ const background_sync_data_t background_sync_data = m_background_sync_data;
++ const hashchain background_synced_chain = m_blockchain;
++ const uint64_t last_block_reward = m_last_block_reward;
++
++ if (m_background_sync_type == BackgroundSyncCustomPassword && !m_wallet_file.empty())
++ {
++ // Reload the wallet from disk
++ load(m_wallet_file, wallet_password);
++ THROW_WALLET_EXCEPTION_IF(!verify_spend_key(recovered_spend_key), error::invalid_spend_key);
++ }
++ m_background_syncing = false;
++
++ // Set the plaintext spend key
++ m_account.set_spend_key(recovered_spend_key);
++
++ // Encrypt the spend key when done if needed
++ epee::misc_utils::auto_scope_leave_caller keys_reencryptor;
++ if (m_ask_password == AskPasswordToDecrypt && !m_unattended && !m_watch_only)
++ keys_reencryptor = epee::misc_utils::create_scope_leave_handler([&, this]{encrypt_keys(wallet_password);});
++
++ // Now we can use the decrypted spend key to process background cache
++ process_background_cache(background_sync_data, background_synced_chain, last_block_reward);
++
++ // Reset the background cache after processing
++ reset_background_sync_data(m_background_sync_data);
++
++ MDEBUG("Background sync stopped");
++}
++//----------------------------------------------------------------------------------------------------
+ wallet2::payment_container wallet2::export_payments() const
+ {
+ payment_container payments;
+diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
+index b540eff6b..bfe3a4f19 100644
+--- a/src/wallet/wallet2.h
++++ b/src/wallet/wallet2.h
+@@ -257,6 +257,20 @@ private:
+ BackgroundMiningNo = 2,
+ };
+
++ enum BackgroundSyncType {
++ BackgroundSyncOff = 0,
++ BackgroundSyncReusePassword = 1,
++ BackgroundSyncCustomPassword = 2,
++ };
++
++ static BackgroundSyncType background_sync_type_from_str(const std::string &background_sync_type_str)
++ {
++ if (background_sync_type_str == "off") return BackgroundSyncOff;
++ if (background_sync_type_str == "reuse-wallet-password") return BackgroundSyncReusePassword;
++ if (background_sync_type_str == "custom-background-password") return BackgroundSyncCustomPassword;
++ throw std::logic_error("Unknown background sync type");
++ };
++
+ enum ExportFormat {
+ Binary = 0,
+ Ascii,
+@@ -283,7 +297,12 @@ private:
+ //! Just parses variables.
+ static std::unique_ptr<wallet2> make_dummy(const boost::program_options::variables_map& vm, bool unattended, const std::function<boost::optional<password_container>(const char *, bool)> &password_prompter);
+
+- static bool verify_password(const std::string& keys_file_name, const epee::wipeable_string& password, bool no_spend_key, hw::device &hwdev, uint64_t kdf_rounds);
++ static bool verify_password(const std::string& keys_file_name, const epee::wipeable_string& password, bool no_spend_key, hw::device &hwdev, uint64_t kdf_rounds)
++ {
++ crypto::secret_key spend_key = crypto::null_skey;
++ return verify_password(keys_file_name, password, no_spend_key, hwdev, kdf_rounds, spend_key);
++ };
++ static bool verify_password(const std::string& keys_file_name, const epee::wipeable_string& password, bool no_spend_key, hw::device &hwdev, uint64_t kdf_rounds, crypto::secret_key &spend_key_out);
+ static bool query_device(hw::device::device_type& device_type, const std::string& keys_file_name, const epee::wipeable_string& password, uint64_t kdf_rounds = 1);
+
+ wallet2(cryptonote::network_type nettype = cryptonote::MAINNET, uint64_t kdf_rounds = 1, bool unattended = false, std::unique_ptr<epee::net_utils::http::http_client_factory> http_client_factory = std::unique_ptr<epee::net_utils::http::http_client_factory>(new net::http::client_factory()));
+@@ -793,6 +812,54 @@ private:
+ END_SERIALIZE()
+ };
+
++ struct background_synced_tx
++ {
++ uint64_t index_in_background_sync_data;
++ cryptonote::transaction tx;
++ std::vector<uint64_t> output_indices;
++ uint64_t height;
++ uint64_t block_timestamp;
++ bool double_spend_seen;
++
++ BEGIN_SERIALIZE_OBJECT()
++ VERSION_FIELD(0)
++ VARINT_FIELD(index_in_background_sync_data)
++
++ // prune tx; don't need to keep signature data
++ if (!tx.serialize_base(ar))
++ return false;
++
++ FIELD(output_indices)
++ VARINT_FIELD(height)
++ VARINT_FIELD(block_timestamp)
++ FIELD(double_spend_seen)
++ END_SERIALIZE()
++ };
++
++ struct background_sync_data_t
++ {
++ bool first_refresh_done;
++ uint64_t start_height;
++ serializable_unordered_map<crypto::hash, background_synced_tx> txs;
++
++ // Relevant wallet settings
++ uint64_t wallet_refresh_from_block_height;
++ size_t subaddress_lookahead_major;
++ size_t subaddress_lookahead_minor;
++ RefreshType wallet_refresh_type;
++
++ BEGIN_SERIALIZE_OBJECT()
++ VERSION_FIELD(0)
++ FIELD(first_refresh_done)
++ FIELD(start_height)
++ FIELD(txs)
++ FIELD(wallet_refresh_from_block_height)
++ VARINT_FIELD(subaddress_lookahead_major)
++ VARINT_FIELD(subaddress_lookahead_minor)
++ VARINT_FIELD(wallet_refresh_type)
++ END_SERIALIZE()
++ };
++
+ typedef std::tuple<uint64_t, crypto::public_key, rct::key> get_outs_entry;
+
+ struct parsed_block
+@@ -989,7 +1056,8 @@ private:
+ /*!
+ * \brief verifies given password is correct for default wallet keys file
+ */
+- bool verify_password(const epee::wipeable_string& password);
++ bool verify_password(const epee::wipeable_string& password) {crypto::secret_key key = crypto::null_skey; return verify_password(password, key);};
++ bool verify_password(const epee::wipeable_string& password, crypto::secret_key &spend_key_out);
+ cryptonote::account_base& get_account(){return m_account;}
+ const cryptonote::account_base& get_account()const{return m_account;}
+
+@@ -1093,6 +1161,7 @@ private:
+ cryptonote::network_type nettype() const { return m_nettype; }
+ bool watch_only() const { return m_watch_only; }
+ bool multisig(bool *ready = NULL, uint32_t *threshold = NULL, uint32_t *total = NULL) const;
++ bool is_background_wallet() const { return m_is_background_wallet; }
+ bool has_multisig_partial_key_images() const;
+ bool has_unknown_key_images() const;
+ bool get_multisig_seed(epee::wipeable_string& seed, const epee::wipeable_string &passphrase = std::string()) const;
+@@ -1300,6 +1369,11 @@ private:
+ return;
+ }
+ a & m_has_ever_refreshed_from_node;
++ if ((m_background_sync_type == BackgroundSyncCustomPassword && m_is_background_wallet) ||
++ (m_background_sync_type == BackgroundSyncReusePassword && !m_is_background_wallet))
++ {
++ a & m_background_sync_data;
++ }
+ }
+
+ BEGIN_SERIALIZE_OBJECT()
+@@ -1336,6 +1410,11 @@ private:
+ return true;
+ }
+ FIELD(m_has_ever_refreshed_from_node)
++ if ((m_background_sync_type == BackgroundSyncCustomPassword && m_is_background_wallet) ||
++ (m_background_sync_type == BackgroundSyncReusePassword && !m_is_background_wallet))
++ {
++ FIELD(m_background_sync_data)
++ }
+ END_SERIALIZE()
+
+ /*!
+@@ -1351,6 +1430,8 @@ private:
+ * \return Whether path is valid format
+ */
+ static bool wallet_valid_path_format(const std::string& file_path);
++ static std::string make_background_wallet_file_name(const std::string &wallet_file);
++ static std::string make_background_keys_file_name(const std::string &wallet_file);
+ static bool parse_long_payment_id(const std::string& payment_id_str, crypto::hash& payment_id);
+ static bool parse_short_payment_id(const std::string& payment_id_str, crypto::hash8& payment_id);
+ static bool parse_payment_id(const std::string& payment_id_str, crypto::hash& payment_id);
+@@ -1399,6 +1480,9 @@ private:
+ void ignore_outputs_below(uint64_t value) { m_ignore_outputs_below = value; }
+ bool track_uses() const { return m_track_uses; }
+ void track_uses(bool value) { m_track_uses = value; }
++ BackgroundSyncType background_sync_type() const { return m_background_sync_type; }
++ void setup_background_sync(BackgroundSyncType background_sync_type, const epee::wipeable_string &wallet_password, const boost::optional<epee::wipeable_string> &background_cache_password);
++ bool is_background_syncing() const { return m_background_syncing; }
+ bool show_wallet_name_when_locked() const { return m_show_wallet_name_when_locked; }
+ void show_wallet_name_when_locked(bool value) { m_show_wallet_name_when_locked = value; }
+ BackgroundMiningSetupType setup_background_mining() const { return m_setup_background_mining; }
+@@ -1425,6 +1509,7 @@ private:
+ void enable_multisig(bool enable) { m_enable_multisig = enable; }
+ bool is_mismatched_daemon_version_allowed() const { return m_allow_mismatched_daemon_version; }
+ void allow_mismatched_daemon_version(bool allow_mismatch) { m_allow_mismatched_daemon_version = allow_mismatch; }
++ uint64_t kdf_rounds() const { return m_kdf_rounds; };
+
+ bool get_tx_key_cached(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, const boost::optional<cryptonote::account_public_address> &single_destination_subaddress = boost::none);
+@@ -1714,6 +1799,9 @@ private:
+ uint64_t get_bytes_sent() const;
+ uint64_t get_bytes_received() const;
+
++ void start_background_sync();
++ void stop_background_sync(const epee::wipeable_string &wallet_password, const crypto::secret_key &spend_secret_key = crypto::null_skey);
++
+ // MMS -------------------------------------------------------------------------------------------------
+ mms::message_store& get_message_store() { return m_message_store; };
+ const mms::message_store& get_message_store() const { return m_message_store; };
+@@ -1749,6 +1837,9 @@ private:
+ * \return Whether it was successful.
+ */
+ bool store_keys(const std::string& keys_file_name, const epee::wipeable_string& password, bool watch_only = false);
++ bool store_keys(const std::string& keys_file_name, const crypto::chacha_key& key, bool watch_only = false, bool background_keys_file = false);
++ boost::optional<wallet2::keys_file_data> get_keys_file_data(const crypto::chacha_key& key, bool watch_only = false, bool background_keys_file = false);
++ bool store_keys_file_data(const std::string& keys_file_name, wallet2::keys_file_data &keys_file_data, bool background_keys_file = false);
+ /*!
+ * \brief Load wallet keys information from wallet file.
+ * \param keys_file_name Name of wallet file
+@@ -1762,6 +1853,7 @@ private:
+ */
+ bool load_keys_buf(const std::string& keys_buf, const epee::wipeable_string& password);
+ bool load_keys_buf(const std::string& keys_buf, const epee::wipeable_string& password, boost::optional<crypto::chacha_key>& keys_to_encrypt);
++ void load_wallet_cache(const bool use_fs, const std::string& cache_buf = "");
+ void process_new_transaction(const crypto::hash &txid, const cryptonote::transaction& tx, const std::vector<uint64_t> &o_indices, uint64_t height, uint8_t block_version, uint64_t ts, bool miner_tx, bool pool, bool double_spend_seen, const tx_cache_data &tx_cache_data, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache = NULL, bool ignore_callbacks = false);
+ bool should_skip_block(const cryptonote::block &b, uint64_t height) const;
+ void process_new_blockchain_entry(const cryptonote::block& b, const cryptonote::block_complete_entry& bche, const parsed_block &parsed_block, const crypto::hash& bl_id, uint64_t height, const std::vector<tx_cache_data> &tx_cache_data, size_t tx_cache_data_offset, std::map<std::pair<uint64_t, uint64_t>, size_t> *output_tracker_cache = NULL);
+@@ -1770,6 +1862,7 @@ private:
+ void get_short_chain_history(std::list<crypto::hash>& ids, uint64_t granularity = 1) const;
+ bool clear();
+ void clear_soft(bool keep_key_images=false);
++ void clear_user_data();
+ void pull_blocks(bool first, bool try_incremental, uint64_t start_height, uint64_t& blocks_start_height, const std::list<crypto::hash> &short_chain_history, std::vector<cryptonote::block_complete_entry> &blocks, std::vector<cryptonote::COMMAND_RPC_GET_BLOCKS_FAST::block_output_indices> &o_indices, uint64_t &current_height);
+ void pull_hashes(uint64_t start_height, uint64_t& blocks_start_height, const std::list<crypto::hash> &short_chain_history, std::vector<crypto::hash> &hashes);
+ void fast_refresh(uint64_t stop_height, uint64_t &blocks_start_height, std::list<crypto::hash> &short_chain_history, bool force = false);
+@@ -1821,10 +1914,23 @@ private:
+ bool get_ring(const crypto::chacha_key &key, const crypto::key_image &key_image, std::vector<uint64_t> &outs);
+ crypto::chacha_key get_ringdb_key();
+ void setup_keys(const epee::wipeable_string &password);
++ const crypto::chacha_key get_cache_key();
++ void verify_password_with_cached_key(const epee::wipeable_string &password);
++ void verify_password_with_cached_key(const crypto::chacha_key &key);
+ size_t get_transfer_details(const crypto::key_image &ki) const;
+ tx_entry_data get_tx_entries(const std::unordered_set<crypto::hash> &txids);
+ void sort_scan_tx_entries(std::vector<process_tx_entry_t> &unsorted_tx_entries);
+ void process_scan_txs(const tx_entry_data &txs_to_scan, const tx_entry_data &txs_to_reprocess, const std::unordered_set<crypto::hash> &tx_hashes_to_reprocess, detached_blockchain_data &dbd);
++ void write_background_sync_wallet(const epee::wipeable_string &wallet_password, const epee::wipeable_string &background_cache_password);
++ void process_background_cache_on_open();
++ void process_background_cache(const background_sync_data_t &background_sync_data, const hashchain &background_chain, uint64_t last_block_reward);
++ void reset_background_sync_data(background_sync_data_t &background_sync_data);
++ void store_background_cache(const crypto::chacha_key &custom_background_key, const bool do_reset_background_sync_data = true);
++ void store_background_keys(const crypto::chacha_key &custom_background_key);
++
++ bool lock_background_keys_file(const std::string &background_keys_file);
++ bool unlock_background_keys_file();
++ bool is_background_keys_file_locked() const;
+
+ void register_devices();
+ hw::device& lookup_device(const std::string & device_descriptor);
+@@ -1940,6 +2046,11 @@ private:
+ uint64_t m_ignore_outputs_above;
+ uint64_t m_ignore_outputs_below;
+ bool m_track_uses;
++ bool m_is_background_wallet;
++ BackgroundSyncType m_background_sync_type;
++ bool m_background_syncing;
++ bool m_processing_background_cache;
++ background_sync_data_t m_background_sync_data;
+ bool m_show_wallet_name_when_locked;
+ uint32_t m_inactivity_lock_timeout;
+ BackgroundMiningSetupType m_setup_background_mining;
+@@ -1985,6 +2096,7 @@ private:
+
+ uint64_t m_last_block_reward;
+ std::unique_ptr<tools::file_locker> m_keys_file_locker;
++ std::unique_ptr<tools::file_locker> m_background_keys_file_locker;
+
+ mms::message_store m_message_store;
+ bool m_original_keys_available;
+@@ -1992,6 +2104,7 @@ private:
+ crypto::secret_key m_original_view_secret_key;
+
+ crypto::chacha_key m_cache_key;
++ boost::optional<crypto::chacha_key> m_custom_background_key = boost::none;
+ std::shared_ptr<wallet_keys_unlocker> m_encrypt_keys_after_refresh;
+
+ bool m_unattended;
+@@ -2025,6 +2138,8 @@ BOOST_CLASS_VERSION(tools::wallet2::signed_tx_set, 1)
+ BOOST_CLASS_VERSION(tools::wallet2::tx_construction_data, 4)
+ BOOST_CLASS_VERSION(tools::wallet2::pending_tx, 3)
+ BOOST_CLASS_VERSION(tools::wallet2::multisig_sig, 1)
++BOOST_CLASS_VERSION(tools::wallet2::background_synced_tx, 0)
++BOOST_CLASS_VERSION(tools::wallet2::background_sync_data_t, 0)
+
+ namespace boost
+ {
+@@ -2523,6 +2638,29 @@ namespace boost
+ return;
+ a & x.multisig_sigs;
+ }
++
++ template <class Archive>
++ inline void serialize(Archive& a, tools::wallet2::background_synced_tx &x, const boost::serialization::version_type ver)
++ {
++ a & x.index_in_background_sync_data;
++ a & x.tx;
++ a & x.output_indices;
++ a & x.height;
++ a & x.block_timestamp;
++ a & x.double_spend_seen;
++ }
++
++ template <class Archive>
++ inline void serialize(Archive& a, tools::wallet2::background_sync_data_t &x, const boost::serialization::version_type ver)
++ {
++ a & x.first_refresh_done;
++ a & x.start_height;
++ a & x.txs.parent();
++ a & x.wallet_refresh_from_block_height;
++ a & x.subaddress_lookahead_major;
++ a & x.subaddress_lookahead_minor;
++ a & x.wallet_refresh_type;
++ }
+ }
+ }
+
+diff --git a/src/wallet/wallet_errors.h b/src/wallet/wallet_errors.h
+index 1f7e1c75d..d17b721a9 100644
+--- a/src/wallet/wallet_errors.h
++++ b/src/wallet/wallet_errors.h
+@@ -63,6 +63,7 @@ namespace tools
+ // invalid_password
+ // invalid_priority
+ // invalid_multisig_seed
++ // invalid_spend_key
+ // refresh_error *
+ // acc_outs_lookup_error
+ // block_parse_error
+@@ -96,6 +97,9 @@ namespace tools
+ // wallet_files_doesnt_correspond
+ // scan_tx_error *
+ // wont_reprocess_recent_txs_via_untrusted_daemon
++ // background_sync_error *
++ // background_wallet_already_open
++ // background_custom_password_same_as_wallet_password
+ //
+ // * - class with protected ctor
+
+@@ -303,6 +307,16 @@ namespace tools
+ std::string to_string() const { return wallet_logic_error::to_string(); }
+ };
+
++ struct invalid_spend_key : public wallet_logic_error
++ {
++ explicit invalid_spend_key(std::string&& loc)
++ : wallet_logic_error(std::move(loc), "invalid spend key")
++ {
++ }
++
++ std::string to_string() const { return wallet_logic_error::to_string(); }
++ };
++
+ //----------------------------------------------------------------------------------------------------
+ struct invalid_pregenerated_random : public wallet_logic_error
+ {
+@@ -944,6 +958,31 @@ namespace tools
+ }
+ };
+ //----------------------------------------------------------------------------------------------------
++ struct background_sync_error : public wallet_logic_error
++ {
++ protected:
++ explicit background_sync_error(std::string&& loc, const std::string& message)
++ : wallet_logic_error(std::move(loc), message)
++ {
++ }
++ };
++ //----------------------------------------------------------------------------------------------------
++ struct background_wallet_already_open : public background_sync_error
++ {
++ explicit background_wallet_already_open(std::string&& loc, const std::string& background_wallet_file)
++ : background_sync_error(std::move(loc), "background wallet " + background_wallet_file + " is already opened by another wallet program")
++ {
++ }
++ };
++ //----------------------------------------------------------------------------------------------------
++ struct background_custom_password_same_as_wallet_password : public background_sync_error
++ {
++ explicit background_custom_password_same_as_wallet_password(std::string&& loc)
++ : background_sync_error(std::move(loc), "custom background password must be different than wallet password")
++ {
++ }
++ };
++ //----------------------------------------------------------------------------------------------------
+
+ #if !defined(_MSC_VER)
+
+diff --git a/src/wallet/wallet_rpc_server.cpp b/src/wallet/wallet_rpc_server.cpp
+index 4e42d64cd..822fc828b 100644
+--- a/src/wallet/wallet_rpc_server.cpp
++++ b/src/wallet/wallet_rpc_server.cpp
+@@ -73,6 +73,54 @@ using namespace epee;
+ } \
+ } while(0)
+
++#define CHECK_IF_BACKGROUND_SYNCING() \
++ do \
++ { \
++ if (!m_wallet) { return not_open(er); } \
++ if (m_wallet->is_background_wallet()) \
++ { \
++ er.code = WALLET_RPC_ERROR_CODE_IS_BACKGROUND_WALLET; \
++ er.message = "This command is disabled for background wallets."; \
++ return false; \
++ } \
++ if (m_wallet->is_background_syncing()) \
++ { \
++ er.code = WALLET_RPC_ERROR_CODE_IS_BACKGROUND_SYNCING; \
++ er.message = "This command is disabled while background syncing. Stop background syncing to use this command."; \
++ return false; \
++ } \
++ } while(0)
++
++#define PRE_VALIDATE_BACKGROUND_SYNC() \
++ do \
++ { \
++ if (!m_wallet) { return not_open(er); } \
++ if (m_restricted) \
++ { \
++ er.code = WALLET_RPC_ERROR_CODE_DENIED; \
++ er.message = "Command unavailable in restricted mode."; \
++ return false; \
++ } \
++ if (m_wallet->key_on_device()) \
++ { \
++ er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR; \
++ er.message = "Command not supported by HW wallet"; \
++ return false; \
++ } \
++ if (m_wallet->multisig()) \
++ { \
++ er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR; \
++ er.message = "Multisig wallet cannot enable background sync"; \
++ return false; \
++ } \
++ if (m_wallet->watch_only()) \
++ { \
++ er.code = WALLET_RPC_ERROR_CODE_WATCH_ONLY; \
++ er.message = "Watch-only wallet cannot enable background sync"; \
++ return false; \
++ } \
++ } while (0)
++
+ namespace
+ {
+ const command_line::arg_descriptor<std::string, true> arg_rpc_bind_port = {"rpc-bind-port", "Sets bind port for server"};
+@@ -291,6 +339,9 @@ namespace tools
+ {
+ if (!m_wallet)
+ return;
++ // Background mining can be toggled from the main wallet
++ if (m_wallet->is_background_wallet() || m_wallet->is_background_syncing())
++ return;
+
+ tools::wallet2::BackgroundMiningSetupType setup = m_wallet->setup_background_mining();
+ if (setup == tools::wallet2::BackgroundMiningNo)
+@@ -582,6 +633,7 @@ namespace tools
+ bool wallet_rpc_server::on_create_address(const wallet_rpc::COMMAND_RPC_CREATE_ADDRESS::request& req, wallet_rpc::COMMAND_RPC_CREATE_ADDRESS::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ if (req.count < 1 || req.count > 64) {
+@@ -619,6 +671,7 @@ namespace tools
+ bool wallet_rpc_server::on_label_address(const wallet_rpc::COMMAND_RPC_LABEL_ADDRESS::request& req, wallet_rpc::COMMAND_RPC_LABEL_ADDRESS::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->set_subaddress_label(req.index, req.label);
+@@ -681,6 +734,7 @@ namespace tools
+ bool wallet_rpc_server::on_create_account(const wallet_rpc::COMMAND_RPC_CREATE_ACCOUNT::request& req, wallet_rpc::COMMAND_RPC_CREATE_ACCOUNT::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->add_subaddress_account(req.label);
+@@ -698,6 +752,7 @@ namespace tools
+ bool wallet_rpc_server::on_label_account(const wallet_rpc::COMMAND_RPC_LABEL_ACCOUNT::request& req, wallet_rpc::COMMAND_RPC_LABEL_ACCOUNT::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->set_subaddress_label({req.account_index, 0}, req.label);
+@@ -713,6 +768,7 @@ namespace tools
+ bool wallet_rpc_server::on_get_account_tags(const wallet_rpc::COMMAND_RPC_GET_ACCOUNT_TAGS::request& req, wallet_rpc::COMMAND_RPC_GET_ACCOUNT_TAGS::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ const std::pair<std::map<std::string, std::string>, std::vector<std::string>> account_tags = m_wallet->get_account_tags();
+ for (const std::pair<const std::string, std::string>& p : account_tags.first)
+ {
+@@ -732,6 +788,7 @@ namespace tools
+ bool wallet_rpc_server::on_tag_accounts(const wallet_rpc::COMMAND_RPC_TAG_ACCOUNTS::request& req, wallet_rpc::COMMAND_RPC_TAG_ACCOUNTS::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->set_account_tag(req.accounts, req.tag);
+@@ -747,6 +804,7 @@ namespace tools
+ bool wallet_rpc_server::on_untag_accounts(const wallet_rpc::COMMAND_RPC_UNTAG_ACCOUNTS::request& req, wallet_rpc::COMMAND_RPC_UNTAG_ACCOUNTS::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->set_account_tag(req.accounts, "");
+@@ -762,6 +820,7 @@ namespace tools
+ bool wallet_rpc_server::on_set_account_tag_description(const wallet_rpc::COMMAND_RPC_SET_ACCOUNT_TAG_DESCRIPTION::request& req, wallet_rpc::COMMAND_RPC_SET_ACCOUNT_TAG_DESCRIPTION::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->set_account_tag_description(req.tag, req.description);
+@@ -792,6 +851,7 @@ namespace tools
+ bool wallet_rpc_server::on_freeze(const wallet_rpc::COMMAND_RPC_FREEZE::request& req, wallet_rpc::COMMAND_RPC_FREEZE::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ if (req.key_image.empty())
+@@ -820,6 +880,7 @@ namespace tools
+ bool wallet_rpc_server::on_thaw(const wallet_rpc::COMMAND_RPC_THAW::request& req, wallet_rpc::COMMAND_RPC_THAW::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ if (req.key_image.empty())
+@@ -848,6 +909,7 @@ namespace tools
+ bool wallet_rpc_server::on_frozen(const wallet_rpc::COMMAND_RPC_FROZEN::request& req, wallet_rpc::COMMAND_RPC_FROZEN::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ if (req.key_image.empty())
+@@ -875,6 +937,8 @@ namespace tools
+ //------------------------------------------------------------------------------------------------------------------------------
+ bool wallet_rpc_server::validate_transfer(const std::list<wallet_rpc::transfer_destination>& destinations, const std::string& payment_id, std::vector<cryptonote::tx_destination_entry>& dsts, std::vector<uint8_t>& extra, bool at_least_one_destination, epee::json_rpc::error& er)
+ {
++ CHECK_IF_BACKGROUND_SYNCING();
++
+ crypto::hash8 integrated_payment_id = crypto::null_hash8;
+ std::string extra_nonce;
+ for (auto it = destinations.begin(); it != destinations.end(); it++)
+@@ -1192,6 +1256,7 @@ namespace tools
+ }
+
+ CHECK_MULTISIG_ENABLED();
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ cryptonote::blobdata blob;
+ if (!epee::string_tools::parse_hexstr_to_binbuff(req.unsigned_txset, blob))
+@@ -1273,6 +1338,7 @@ namespace tools
+ er.message = "command not supported by watch-only wallet";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+ if(req.unsigned_txset.empty() && req.multisig_txset.empty())
+ {
+ er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR;
+@@ -1542,6 +1608,7 @@ namespace tools
+ }
+
+ CHECK_MULTISIG_ENABLED();
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ try
+ {
+@@ -2091,6 +2158,7 @@ namespace tools
+ er.message = "The wallet is watch-only. Cannot retrieve seed.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+ if (!m_wallet->is_deterministic())
+ {
+ er.code = WALLET_RPC_ERROR_CODE_NON_DETERMINISTIC;
+@@ -2119,6 +2187,7 @@ namespace tools
+ er.message = "The wallet is watch-only. Cannot retrieve spend key.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+ epee::wipeable_string key = epee::to_hex::wipeable_string(m_wallet->get_account().get_keys().m_spend_secret_key);
+ res.key = std::string(key.data(), key.size());
+ }
+@@ -2140,6 +2209,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ try
+ {
+@@ -2153,6 +2223,79 @@ namespace tools
+ return true;
+ }
+ //------------------------------------------------------------------------------------------------------------------------------
++ bool wallet_rpc_server::on_setup_background_sync(const wallet_rpc::COMMAND_RPC_SETUP_BACKGROUND_SYNC::request& req, wallet_rpc::COMMAND_RPC_SETUP_BACKGROUND_SYNC::response& res, epee::json_rpc::error& er, const connection_context *ctx)
++ {
++ try
++ {
++ PRE_VALIDATE_BACKGROUND_SYNC();
++ const tools::wallet2::BackgroundSyncType background_sync_type = tools::wallet2::background_sync_type_from_str(req.background_sync_type);
++ boost::optional<epee::wipeable_string> background_cache_password = boost::none;
++ if (background_sync_type == tools::wallet2::BackgroundSyncCustomPassword)
++ background_cache_password = boost::optional<epee::wipeable_string>(req.background_cache_password);
++ m_wallet->setup_background_sync(background_sync_type, req.wallet_password, background_cache_password);
++ }
++ catch (...)
++ {
++ handle_rpc_exception(std::current_exception(), er, WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR);
++ return false;
++ }
++ return true;
++ }
++ //------------------------------------------------------------------------------------------------------------------------------
++ bool wallet_rpc_server::on_start_background_sync(const wallet_rpc::COMMAND_RPC_START_BACKGROUND_SYNC::request& req, wallet_rpc::COMMAND_RPC_START_BACKGROUND_SYNC::response& res, epee::json_rpc::error& er, const connection_context *ctx)
++ {
++ try
++ {
++ PRE_VALIDATE_BACKGROUND_SYNC();
++ m_wallet->start_background_sync();
++ }
++ catch (...)
++ {
++ handle_rpc_exception(std::current_exception(), er, WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR);
++ return false;
++ }
++ return true;
++ }
++ //------------------------------------------------------------------------------------------------------------------------------
++ bool wallet_rpc_server::on_stop_background_sync(const wallet_rpc::COMMAND_RPC_STOP_BACKGROUND_SYNC::request& req, wallet_rpc::COMMAND_RPC_STOP_BACKGROUND_SYNC::response& res, epee::json_rpc::error& er, const connection_context *ctx)
++ {
++ try
++ {
++ PRE_VALIDATE_BACKGROUND_SYNC();
++ crypto::secret_key spend_secret_key = crypto::null_skey;
++
++ // Load the spend key from seed if seed is provided
++ if (!req.seed.empty())
++ {
++ crypto::secret_key recovery_key;
++ std::string language;
++
++ if (!crypto::ElectrumWords::words_to_bytes(req.seed, recovery_key, language))
++ {
++ er.code = WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR;
++ er.message = "Electrum-style word list failed verification";
++ return false;
++ }
++
++ if (!req.seed_offset.empty())
++ recovery_key = cryptonote::decrypt_key(recovery_key, req.seed_offset);
++
++ // generate spend key
++ cryptonote::account_base account;
++ account.generate(recovery_key, true, false);
++ spend_secret_key = account.get_keys().m_spend_secret_key;
++ }
++
++ m_wallet->stop_background_sync(req.wallet_password, spend_secret_key);
++ }
++ catch (...)
++ {
++ handle_rpc_exception(std::current_exception(), er, WALLET_RPC_ERROR_CODE_UNKNOWN_ERROR);
++ return false;
++ }
++ return true;
++ }
++ //------------------------------------------------------------------------------------------------------------------------------
+ bool wallet_rpc_server::on_sign(const wallet_rpc::COMMAND_RPC_SIGN::request& req, wallet_rpc::COMMAND_RPC_SIGN::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
+@@ -2162,6 +2305,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ tools::wallet2::message_signature_type_t signature_type = tools::wallet2::sign_with_spend_key;
+ if (req.signature_type == "spend" || req.signature_type == "")
+@@ -2254,6 +2398,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ if (req.txids.size() != req.notes.size())
+ {
+@@ -2326,6 +2471,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ m_wallet->set_attribute(req.key, req.value);
+
+@@ -2353,6 +2499,7 @@ namespace tools
+ bool wallet_rpc_server::on_get_tx_key(const wallet_rpc::COMMAND_RPC_GET_TX_KEY::request& req, wallet_rpc::COMMAND_RPC_GET_TX_KEY::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ crypto::hash txid;
+ if (!epee::string_tools::hex_to_pod(req.txid, txid))
+@@ -2444,6 +2591,7 @@ namespace tools
+ bool wallet_rpc_server::on_get_tx_proof(const wallet_rpc::COMMAND_RPC_GET_TX_PROOF::request& req, wallet_rpc::COMMAND_RPC_GET_TX_PROOF::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ crypto::hash txid;
+ if (!epee::string_tools::hex_to_pod(req.txid, txid))
+@@ -2560,6 +2708,7 @@ namespace tools
+ bool wallet_rpc_server::on_get_reserve_proof(const wallet_rpc::COMMAND_RPC_GET_RESERVE_PROOF::request& req, wallet_rpc::COMMAND_RPC_GET_RESERVE_PROOF::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ boost::optional<std::pair<uint32_t, uint64_t>> account_minreserve;
+ if (!req.all)
+@@ -2802,6 +2951,7 @@ namespace tools
+ er.message = "command not supported by HW wallet";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ try
+ {
+@@ -2831,6 +2981,7 @@ namespace tools
+ er.message = "command not supported by HW wallet";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ cryptonote::blobdata blob;
+ if (!epee::string_tools::parse_hexstr_to_binbuff(req.outputs_data_hex, blob))
+@@ -2856,6 +3007,7 @@ namespace tools
+ bool wallet_rpc_server::on_export_key_images(const wallet_rpc::COMMAND_RPC_EXPORT_KEY_IMAGES::request& req, wallet_rpc::COMMAND_RPC_EXPORT_KEY_IMAGES::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ std::pair<uint64_t, std::vector<std::pair<crypto::key_image, crypto::signature>>> ski = m_wallet->export_key_images(req.all);
+@@ -2892,6 +3044,7 @@ namespace tools
+ er.message = "This command requires a trusted daemon.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ std::vector<std::pair<crypto::key_image, crypto::signature>> ski;
+@@ -2960,6 +3113,7 @@ namespace tools
+ bool wallet_rpc_server::on_get_address_book(const wallet_rpc::COMMAND_RPC_GET_ADDRESS_BOOK_ENTRY::request& req, wallet_rpc::COMMAND_RPC_GET_ADDRESS_BOOK_ENTRY::response& res, epee::json_rpc::error& er, const connection_context *ctx)
+ {
+ if (!m_wallet) return not_open(er);
++ CHECK_IF_BACKGROUND_SYNCING();
+ const auto ab = m_wallet->get_address_book();
+ if (req.entries.empty())
+ {
+@@ -3005,6 +3159,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ cryptonote::address_parse_info info;
+ er.message = "";
+@@ -3047,6 +3202,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ const auto ab = m_wallet->get_address_book();
+ if (req.index >= ab.size())
+@@ -3109,6 +3265,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ const auto ab = m_wallet->get_address_book();
+ if (req.index >= ab.size())
+@@ -3179,6 +3336,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ std::unordered_set<crypto::hash> txids;
+ std::list<std::string>::const_iterator i = req.txids.begin();
+@@ -3218,6 +3376,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+ try
+ {
+ m_wallet->rescan_spent();
+@@ -3482,6 +3641,7 @@ namespace tools
+ er.message = "Command unavailable in restricted mode.";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+ if (m_wallet->verify_password(req.old_password))
+ {
+ try
+@@ -4009,6 +4169,7 @@ namespace tools
+ er.message = "wallet is watch-only and cannot be made multisig";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ res.multisig_info = m_wallet->get_multisig_first_kex_msg();
+ return true;
+@@ -4036,6 +4197,7 @@ namespace tools
+ er.message = "wallet is watch-only and cannot be made multisig";
+ return false;
+ }
++ CHECK_IF_BACKGROUND_SYNCING();
+
+ try
+ {
+diff --git a/src/wallet/wallet_rpc_server.h b/src/wallet/wallet_rpc_server.h
+index 3308d1751..c2329aafe 100644
+--- a/src/wallet/wallet_rpc_server.h
++++ b/src/wallet/wallet_rpc_server.h
+@@ -160,6 +160,9 @@ namespace tools
+ MAP_JON_RPC_WE("set_log_categories", on_set_log_categories, wallet_rpc::COMMAND_RPC_SET_LOG_CATEGORIES)
+ MAP_JON_RPC_WE("estimate_tx_size_and_weight", on_estimate_tx_size_and_weight, wallet_rpc::COMMAND_RPC_ESTIMATE_TX_SIZE_AND_WEIGHT)
+ MAP_JON_RPC_WE("get_version", on_get_version, wallet_rpc::COMMAND_RPC_GET_VERSION)
++ MAP_JON_RPC_WE("setup_background_sync", on_setup_background_sync, wallet_rpc::COMMAND_RPC_SETUP_BACKGROUND_SYNC)
++ MAP_JON_RPC_WE("start_background_sync", on_start_background_sync, wallet_rpc::COMMAND_RPC_START_BACKGROUND_SYNC)
++ MAP_JON_RPC_WE("stop_background_sync", on_stop_background_sync, wallet_rpc::COMMAND_RPC_STOP_BACKGROUND_SYNC)
+ END_JSON_RPC_MAP()
+ END_URI_MAP2()
+
+@@ -251,6 +254,9 @@ namespace tools
+ bool on_set_log_categories(const wallet_rpc::COMMAND_RPC_SET_LOG_CATEGORIES::request& req, wallet_rpc::COMMAND_RPC_SET_LOG_CATEGORIES::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
+ bool on_estimate_tx_size_and_weight(const wallet_rpc::COMMAND_RPC_ESTIMATE_TX_SIZE_AND_WEIGHT::request& req, wallet_rpc::COMMAND_RPC_ESTIMATE_TX_SIZE_AND_WEIGHT::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
+ bool on_get_version(const wallet_rpc::COMMAND_RPC_GET_VERSION::request& req, wallet_rpc::COMMAND_RPC_GET_VERSION::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
++ bool on_setup_background_sync(const wallet_rpc::COMMAND_RPC_SETUP_BACKGROUND_SYNC::request& req, wallet_rpc::COMMAND_RPC_SETUP_BACKGROUND_SYNC::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
++ bool on_start_background_sync(const wallet_rpc::COMMAND_RPC_START_BACKGROUND_SYNC::request& req, wallet_rpc::COMMAND_RPC_START_BACKGROUND_SYNC::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
++ bool on_stop_background_sync(const wallet_rpc::COMMAND_RPC_STOP_BACKGROUND_SYNC::request& req, wallet_rpc::COMMAND_RPC_STOP_BACKGROUND_SYNC::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
+
+ //json rpc v2
+ bool on_query_key(const wallet_rpc::COMMAND_RPC_QUERY_KEY::request& req, wallet_rpc::COMMAND_RPC_QUERY_KEY::response& res, epee::json_rpc::error& er, const connection_context *ctx = NULL);
+diff --git a/src/wallet/wallet_rpc_server_commands_defs.h b/src/wallet/wallet_rpc_server_commands_defs.h
+index b6098d95c..a44b56ed6 100644
+--- a/src/wallet/wallet_rpc_server_commands_defs.h
++++ b/src/wallet/wallet_rpc_server_commands_defs.h
+@@ -2696,5 +2696,69 @@ namespace wallet_rpc
+ typedef epee::misc_utils::struct_init<response_t> response;
+ };
+
++ struct COMMAND_RPC_SETUP_BACKGROUND_SYNC
++ {
++ struct request_t
++ {
++ std::string background_sync_type;
++ std::string wallet_password;
++ std::string background_cache_password;
++
++ BEGIN_KV_SERIALIZE_MAP()
++ KV_SERIALIZE(background_sync_type)
++ KV_SERIALIZE(wallet_password)
++ KV_SERIALIZE_OPT(background_cache_password, (std::string)"")
++ END_KV_SERIALIZE_MAP()
++ };
++ typedef epee::misc_utils::struct_init<request_t> request;
++
++ struct response_t
++ {
++ BEGIN_KV_SERIALIZE_MAP()
++ END_KV_SERIALIZE_MAP()
++ };
++ typedef epee::misc_utils::struct_init<response_t> response;
++ };
++
++ struct COMMAND_RPC_START_BACKGROUND_SYNC
++ {
++ struct request_t
++ {
++ BEGIN_KV_SERIALIZE_MAP()
++ END_KV_SERIALIZE_MAP()
++ };
++ typedef epee::misc_utils::struct_init<request_t> request;
++
++ struct response_t
++ {
++ BEGIN_KV_SERIALIZE_MAP()
++ END_KV_SERIALIZE_MAP()
++ };
++ typedef epee::misc_utils::struct_init<response_t> response;
++ };
++
++ struct COMMAND_RPC_STOP_BACKGROUND_SYNC
++ {
++ struct request_t
++ {
++ std::string wallet_password;
++ std::string seed;
++ std::string seed_offset;
++
++ BEGIN_KV_SERIALIZE_MAP()
++ KV_SERIALIZE(wallet_password)
++ KV_SERIALIZE_OPT(seed, (std::string)"")
++ KV_SERIALIZE_OPT(seed_offset, (std::string)"")
++ END_KV_SERIALIZE_MAP()
++ };
++ typedef epee::misc_utils::struct_init<request_t> request;
++
++ struct response_t
++ {
++ BEGIN_KV_SERIALIZE_MAP()
++ END_KV_SERIALIZE_MAP()
++ };
++ typedef epee::misc_utils::struct_init<response_t> response;
++ };
+ }
+ }
+diff --git a/src/wallet/wallet_rpc_server_error_codes.h b/src/wallet/wallet_rpc_server_error_codes.h
+index 734229380..b964036bd 100644
+--- a/src/wallet/wallet_rpc_server_error_codes.h
++++ b/src/wallet/wallet_rpc_server_error_codes.h
+@@ -79,3 +79,5 @@
+ #define WALLET_RPC_ERROR_CODE_ZERO_AMOUNT -46
+ #define WALLET_RPC_ERROR_CODE_INVALID_SIGNATURE_TYPE -47
+ #define WALLET_RPC_ERROR_CODE_DISABLED -48
++#define WALLET_RPC_ERROR_CODE_IS_BACKGROUND_WALLET -49
++#define WALLET_RPC_ERROR_CODE_IS_BACKGROUND_SYNCING -50
+diff --git a/tests/functional_tests/transfer.py b/tests/functional_tests/transfer.py
+index 4063911f4..39ee86df3 100755
+--- a/tests/functional_tests/transfer.py
++++ b/tests/functional_tests/transfer.py
+@@ -30,6 +30,7 @@
+
+ from __future__ import print_function
+ import json
++import util_resources
+ import pprint
+ from deepdiff import DeepDiff
+ pp = pprint.PrettyPrinter(indent=2)
+@@ -46,6 +47,17 @@ seeds = [
+ 'dilute gutter certain antics pamphlet macro enjoy left slid guarded bogeys upload nineteen bomb jubilee enhanced irritate turnip eggs swung jukebox loudly reduce sedan slid',
+ ]
+
++def diff_transfers(actual_transfers, expected_transfers, ignore_order = True):
++ # The payments containers aren't ordered; re-scanning can lead to diff orders
++ diff = DeepDiff(actual_transfers, expected_transfers, ignore_order = ignore_order)
++ if diff != {}:
++ pp.pprint(diff)
++ assert diff == {}
++
++def diff_incoming_transfers(actual_transfers, expected_transfers):
++ # wallet2 m_transfers container is ordered and order should be the same across rescans
++ diff_transfers(actual_transfers, expected_transfers, ignore_order = False)
++
+ class TransferTest():
+ def run_test(self):
+ self.reset()
+@@ -63,6 +75,8 @@ class TransferTest():
+ self.check_is_key_image_spent()
+ self.check_scan_tx()
+ self.check_subtract_fee_from_outputs()
++ self.check_background_sync()
++ self.check_background_sync_reorg_recovery()
+
+ def reset(self):
+ print('Resetting blockchain')
+@@ -71,6 +85,387 @@ class TransferTest():
+ daemon.pop_blocks(res.height - 1)
+ daemon.flush_txpool()
+
++ def check_background_sync(self):
++ daemon = Daemon()
++
++ print('Testing background sync')
++
++ # Background sync type options
++ REUSE_PASSWORD = 'reuse-wallet-password'
++ CUSTOM_PASSWORD = 'custom-background-password'
++
++ # Some helper functions
++ def stop_with_wrong_inputs(wallet, wallet_password, seed = ''):
++ invalid = False
++ try: wallet.stop_background_sync(wallet_password = wallet_password, seed = seed)
++ except: invalid = True
++ assert invalid
++
++ def open_with_wrong_password(wallet, filename, password):
++ invalid_password = False
++ try: wallet.open_wallet(filename, password = password)
++ except: invalid_password = True
++ assert invalid_password
++
++ def restore_wallet(wallet, seed, filename = '', password = ''):
++ wallet.close_wallet()
++ if filename != '':
++ util_resources.remove_wallet_files(filename)
++ wallet.restore_deterministic_wallet(seed = seed, filename = filename, password = password)
++ wallet.auto_refresh(enable = False)
++ assert wallet.get_transfers() == {}
++
++ def assert_correct_transfers(wallet, expected_transfers, expected_inc_transfers, expected_balance):
++ diff_transfers(wallet.get_transfers(), expected_transfers)
++ diff_incoming_transfers(wallet.incoming_transfers(transfer_type = 'all'), expected_inc_transfers)
++ assert wallet.get_balance().balance == expected_balance
++
++ # Set up sender_wallet. Prepare to sweep single output to receiver.
++ # We're testing a sweep because it makes sure background sync can
++ # properly pick up txs which do not have a change output back to sender.
++ sender_wallet = self.wallet[0]
++ try: sender_wallet.close_wallet()
++ except: pass
++ sender_wallet.restore_deterministic_wallet(seed = seeds[0])
++ sender_wallet.auto_refresh(enable = False)
++ sender_wallet.refresh()
++ res = sender_wallet.incoming_transfers(transfer_type = 'available')
++ unlocked = [x for x in res.transfers if x.unlocked and x.amount > 0]
++ assert len(unlocked) > 0
++ ki = unlocked[0].key_image
++ amount = unlocked[0].amount
++ spent_txid = unlocked[0].tx_hash
++ sender_wallet.refresh()
++ res = sender_wallet.get_transfers()
++ out_len = 0 if 'out' not in res else len(res.out)
++ sender_starting_balance = sender_wallet.get_balance().balance
++
++ # set up receiver_wallet
++ receiver_wallet = self.wallet[1]
++ try: receiver_wallet.close_wallet()
++ except: pass
++ receiver_wallet.restore_deterministic_wallet(seed = seeds[1])
++ receiver_wallet.auto_refresh(enable = False)
++ receiver_wallet.refresh()
++ res = receiver_wallet.get_transfers()
++ in_len = 0 if 'in' not in res else len(res['in'])
++ receiver_starting_balance = receiver_wallet.get_balance().balance
++
++ # transfer from sender_wallet to receiver_wallet
++ dst = '44Kbx4sJ7JDRDV5aAhLJzQCjDz2ViLRduE3ijDZu3osWKBjMGkV1XPk4pfDUMqt1Aiezvephdqm6YD19GKFD9ZcXVUTp6BW'
++ res = sender_wallet.sweep_single(dst, key_image = ki)
++ assert len(res.tx_hash) == 32*2
++ txid = res.tx_hash
++ assert res.fee > 0
++ fee = res.fee
++ assert res.amount == amount - fee
++
++ expected_sender_balance = sender_starting_balance - amount
++ expected_receiver_balance = receiver_starting_balance + (amount - fee)
++
++ print('Checking background sync on outgoing wallet')
++ sender_wallet.setup_background_sync(background_sync_type = REUSE_PASSWORD)
++ sender_wallet.start_background_sync()
++ # Mine block to an uninvolved wallet
++ daemon.generateblocks('46r4nYSevkfBUMhuykdK3gQ98XDqDTYW1hNLaXNvjpsJaSbNtdXh1sKMsdVgqkaihChAzEy29zEDPMR3NHQvGoZCLGwTerK', 1)
++ # sender should still be able to scan the transfer normally because we
++ # spent an output that had a known key image
++ sender_wallet.refresh()
++ transfers = sender_wallet.get_transfers()
++ assert 'pending' not in transfers or len(transfers.pending) == 0
++ assert 'pool' not in transfers or len (transfers.pool) == 0
++ assert len(transfers.out) == out_len + 1
++ tx = [x for x in transfers.out if x.txid == txid]
++ assert len(tx) == 1
++ tx = tx[0]
++ assert tx.amount == amount - fee
++ assert tx.fee == fee
++ assert len(tx.destinations) == 1
++ assert tx.destinations[0].amount == amount - fee
++ assert tx.destinations[0].address == dst
++ incoming_transfers = sender_wallet.incoming_transfers(transfer_type = 'all')
++ assert len([x for x in incoming_transfers.transfers if x.tx_hash == spent_txid and x.key_image == ki and x.spent]) == 1
++ assert sender_wallet.get_balance().balance == expected_sender_balance
++
++ # Restore and check background syncing outgoing wallet
++ restore_wallet(sender_wallet, seeds[0])
++ sender_wallet.setup_background_sync(background_sync_type = REUSE_PASSWORD)
++ sender_wallet.start_background_sync()
++ sender_wallet.refresh()
++ for i, out_tx in enumerate(transfers.out):
++ if 'destinations' in out_tx:
++ del transfers.out[i]['destinations'] # destinations are not expected after wallet restore
++ # sender's balance should be higher because can't detect spends while
++ # background sync enabled, only receives
++ background_bal = sender_wallet.get_balance().balance
++ assert background_bal > expected_sender_balance
++ background_transfers = sender_wallet.get_transfers()
++ assert 'out' not in background_transfers or len(background_transfers.out) == 0
++ assert 'in' in background_transfers and len(background_transfers['in']) > 0
++ background_incoming_transfers = sender_wallet.incoming_transfers(transfer_type = 'all')
++ assert len(background_incoming_transfers) == len(incoming_transfers)
++ assert len([x for x in background_incoming_transfers.transfers if x.spent or x.key_image != '']) == 0
++ assert len([x for x in background_incoming_transfers.transfers if x.tx_hash == spent_txid]) == 1
++
++ # Try to stop background sync with the wrong seed
++ stop_with_wrong_inputs(sender_wallet, wallet_password = '', seed = seeds[1])
++
++ # Stop background sync and check transfers update correctly
++ sender_wallet.stop_background_sync(wallet_password = '', seed = seeds[0])
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ # Check stopping a wallet with wallet files saved to disk
++ for background_sync_type in [REUSE_PASSWORD, CUSTOM_PASSWORD]:
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ background_cache_password = None if background_sync_type == REUSE_PASSWORD else 'background_password'
++ sender_wallet.setup_background_sync(background_sync_type = background_sync_type, wallet_password = 'test_password', background_cache_password = background_cache_password)
++ sender_wallet.start_background_sync()
++ sender_wallet.refresh()
++ assert_correct_transfers(sender_wallet, background_transfers, background_incoming_transfers, background_bal)
++ stop_with_wrong_inputs(sender_wallet, 'wrong_password')
++ sender_wallet.stop_background_sync(wallet_password = 'test_password')
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ # Close wallet while background syncing, then reopen
++ for background_sync_type in [REUSE_PASSWORD, CUSTOM_PASSWORD]:
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ background_cache_password = None if background_sync_type == REUSE_PASSWORD else 'background_password'
++ sender_wallet.setup_background_sync(background_sync_type = background_sync_type, wallet_password = 'test_password', background_cache_password = background_cache_password)
++ sender_wallet.start_background_sync()
++ sender_wallet.refresh()
++ assert_correct_transfers(sender_wallet, background_transfers, background_incoming_transfers, background_bal)
++ sender_wallet.close_wallet()
++ open_with_wrong_password(sender_wallet, 'test1', 'wrong_password')
++ sender_wallet.open_wallet('test1', password = 'test_password')
++ # It should reopen with spend key loaded and correctly scan all transfers
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ # Close wallet while syncing normally, then reopen
++ for background_sync_type in [REUSE_PASSWORD, CUSTOM_PASSWORD]:
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ background_cache_password = None if background_sync_type == REUSE_PASSWORD else 'background_password'
++ sender_wallet.setup_background_sync(background_sync_type = background_sync_type, wallet_password = 'test_password', background_cache_password = background_cache_password)
++ sender_wallet.refresh()
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++ sender_wallet.close_wallet()
++ open_with_wrong_password(sender_wallet, 'test1', 'wrong_password')
++ sender_wallet.open_wallet('test1', password = 'test_password')
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ # Create background cache using custom password, then use it to sync, then reopen main wallet
++ for background_cache_password in ['background_password', '']:
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++ sender_wallet.setup_background_sync(background_sync_type = CUSTOM_PASSWORD, wallet_password = 'test_password', background_cache_password = background_cache_password)
++ assert util_resources.file_exists('test1.background')
++ assert util_resources.file_exists('test1.background.keys')
++ sender_wallet.close_wallet()
++ open_with_wrong_password(sender_wallet, 'test1.background', 'test_password')
++ sender_wallet.open_wallet('test1.background', password = background_cache_password)
++ sender_wallet.refresh()
++ assert_correct_transfers(sender_wallet, background_transfers, background_incoming_transfers, background_bal)
++ sender_wallet.close_wallet()
++ sender_wallet.open_wallet('test1', password = 'test_password')
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ # Check that main wallet keeps background cache encrypted with custom password in sync
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ sender_wallet.setup_background_sync(background_sync_type = background_sync_type, wallet_password = 'test_password', background_cache_password = 'background_password')
++ sender_wallet.refresh()
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++ sender_wallet.close_wallet()
++ sender_wallet.open_wallet('test1.background', password = 'background_password')
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ # Try using wallet password as custom background password
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++ same_password = False
++ try: sender_wallet.setup_background_sync(background_sync_type = CUSTOM_PASSWORD, wallet_password = 'test_password', background_cache_password = 'test_password')
++ except: same_password = True
++ assert same_password
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++
++ # Turn off background sync
++ for background_sync_type in [REUSE_PASSWORD, CUSTOM_PASSWORD]:
++ restore_wallet(sender_wallet, seeds[0], 'test1', 'test_password')
++ background_cache_password = None if background_sync_type == REUSE_PASSWORD else 'background_password'
++ sender_wallet.setup_background_sync(background_sync_type = background_sync_type, wallet_password = 'test_password', background_cache_password = background_cache_password)
++ if background_sync_type == CUSTOM_PASSWORD:
++ assert util_resources.file_exists('test1.background')
++ assert util_resources.file_exists('test1.background.keys')
++ sender_wallet.close_wallet()
++ assert util_resources.file_exists('test1.background')
++ assert util_resources.file_exists('test1.background.keys')
++ else:
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++ sender_wallet.close_wallet()
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++ sender_wallet.open_wallet('test1', password = 'test_password')
++ sender_wallet.setup_background_sync(background_sync_type = 'off', wallet_password = 'test_password')
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++ sender_wallet.close_wallet()
++ assert not util_resources.file_exists('test1.background')
++ assert not util_resources.file_exists('test1.background.keys')
++ sender_wallet.open_wallet('test1', password = 'test_password')
++
++ # Sanity check against outgoing wallet restored at height 0
++ sender_wallet.close_wallet()
++ sender_wallet.restore_deterministic_wallet(seed = seeds[0], restore_height = 0)
++ sender_wallet.refresh()
++ assert_correct_transfers(sender_wallet, transfers, incoming_transfers, expected_sender_balance)
++
++ print('Checking background sync on incoming wallet')
++ receiver_wallet.setup_background_sync(background_sync_type = REUSE_PASSWORD)
++ receiver_wallet.start_background_sync()
++ receiver_wallet.refresh()
++ transfers = receiver_wallet.get_transfers()
++ assert 'pending' not in transfers or len(transfers.pending) == 0
++ assert 'pool' not in transfers or len (transfers.pool) == 0
++ assert len(transfers['in']) == in_len + 1
++ tx = [x for x in transfers['in'] if x.txid == txid]
++ assert len(tx) == 1
++ tx = tx[0]
++ assert tx.amount == amount - fee
++ assert tx.fee == fee
++ incoming_transfers = receiver_wallet.incoming_transfers(transfer_type = 'all')
++ assert len([x for x in incoming_transfers.transfers if x.tx_hash == txid and x.key_image == '' and not x.spent]) == 1
++ assert receiver_wallet.get_balance().balance == expected_receiver_balance
++
++ # Restore and check background syncing incoming wallet
++ restore_wallet(receiver_wallet, seeds[1])
++ receiver_wallet.setup_background_sync(background_sync_type = REUSE_PASSWORD)
++ receiver_wallet.start_background_sync()
++ receiver_wallet.refresh()
++ if 'out' in transfers:
++ for i, out_tx in enumerate(transfers.out):
++ if 'destinations' in out_tx:
++ del transfers.out[i]['destinations'] # destinations are not expected after wallet restore
++ background_bal = receiver_wallet.get_balance().balance
++ assert background_bal >= expected_receiver_balance
++ background_transfers = receiver_wallet.get_transfers()
++ assert 'out' not in background_transfers or len(background_transfers.out) == 0
++ assert 'in' in background_transfers and len(background_transfers['in']) > 0
++ background_incoming_transfers = receiver_wallet.incoming_transfers(transfer_type = 'all')
++ assert len(background_incoming_transfers) == len(incoming_transfers)
++ assert len([x for x in background_incoming_transfers.transfers if x.spent or x.key_image != '']) == 0
++ assert len([x for x in background_incoming_transfers.transfers if x.tx_hash == txid]) == 1
++
++ # Stop background sync and check transfers update correctly
++ receiver_wallet.stop_background_sync(wallet_password = '', seed = seeds[1])
++ diff_transfers(receiver_wallet.get_transfers(), transfers)
++ incoming_transfers = receiver_wallet.incoming_transfers(transfer_type = 'all')
++ assert len(background_incoming_transfers) == len(incoming_transfers)
++ assert len([x for x in incoming_transfers.transfers if x.tx_hash == txid and x.key_image != '' and not x.spent]) == 1
++ assert receiver_wallet.get_balance().balance == expected_receiver_balance
++
++ # Check a fresh incoming wallet with wallet files saved to disk and encrypted with password
++ restore_wallet(receiver_wallet, seeds[1], 'test2', 'test_password')
++ receiver_wallet.setup_background_sync(background_sync_type = REUSE_PASSWORD, wallet_password = 'test_password')
++ receiver_wallet.start_background_sync()
++ receiver_wallet.refresh()
++ assert_correct_transfers(receiver_wallet, background_transfers, background_incoming_transfers, background_bal)
++ stop_with_wrong_inputs(receiver_wallet, 'wrong_password')
++ receiver_wallet.stop_background_sync(wallet_password = 'test_password')
++ assert_correct_transfers(receiver_wallet, transfers, incoming_transfers, expected_receiver_balance)
++
++ # Close receiver's wallet while background sync is enabled then reopen
++ restore_wallet(receiver_wallet, seeds[1], 'test2', 'test_password')
++ receiver_wallet.setup_background_sync(background_sync_type = REUSE_PASSWORD, wallet_password = 'test_password')
++ receiver_wallet.start_background_sync()
++ receiver_wallet.refresh()
++ diff_transfers(receiver_wallet.get_transfers(), background_transfers)
++ diff_incoming_transfers(receiver_wallet.incoming_transfers(transfer_type = 'all'), background_incoming_transfers)
++ assert receiver_wallet.get_balance().balance == background_bal
++ receiver_wallet.close_wallet()
++ receiver_wallet.open_wallet('test2', password = 'test_password')
++ # It should reopen with spend key loaded and correctly scan all transfers
++ assert_correct_transfers(receiver_wallet, transfers, incoming_transfers, expected_receiver_balance)
++
++ # Sanity check against incoming wallet restored at height 0
++ receiver_wallet.close_wallet()
++ receiver_wallet.restore_deterministic_wallet(seed = seeds[1], restore_height = 0)
++ receiver_wallet.refresh()
++ assert_correct_transfers(receiver_wallet, transfers, incoming_transfers, expected_receiver_balance)
++
++ # Clean up
++ util_resources.remove_wallet_files('test1')
++ util_resources.remove_wallet_files('test2')
++ for i in range(2):
++ self.wallet[i].close_wallet()
++ self.wallet[i].restore_deterministic_wallet(seed = seeds[i])
++
++ def check_background_sync_reorg_recovery(self):
++ daemon = Daemon()
++
++ print('Testing background sync reorg recovery')
++
++ # Disconnect daemon from peers
++ daemon.out_peers(0)
++
++ # Background sync type options
++ REUSE_PASSWORD = 'reuse-wallet-password'
++ CUSTOM_PASSWORD = 'custom-background-password'
++
++ for background_sync_type in [REUSE_PASSWORD, CUSTOM_PASSWORD]:
++ # Set up wallet saved to disk
++ sender_wallet = self.wallet[0]
++ sender_wallet.close_wallet()
++ util_resources.remove_wallet_files('test1')
++ sender_wallet.restore_deterministic_wallet(seed = seeds[0], filename = 'test1', password = '')
++ sender_wallet.auto_refresh(enable = False)
++ sender_wallet.refresh()
++ sender_starting_balance = sender_wallet.get_balance().balance
++
++ # Send tx and mine a block
++ amount = 1000000000000
++ assert sender_starting_balance > amount
++ dst = {'address': '44Kbx4sJ7JDRDV5aAhLJzQCjDz2ViLRduE3ijDZu3osWKBjMGkV1XPk4pfDUMqt1Aiezvephdqm6YD19GKFD9ZcXVUTp6BW', 'amount': amount}
++ res = sender_wallet.transfer([dst])
++ assert len(res.tx_hash) == 32*2
++ txid = res.tx_hash
++
++ daemon.generateblocks('46r4nYSevkfBUMhuykdK3gQ98XDqDTYW1hNLaXNvjpsJaSbNtdXh1sKMsdVgqkaihChAzEy29zEDPMR3NHQvGoZCLGwTerK', 1)
++
++ # Make sure the wallet can see the tx
++ sender_wallet.refresh()
++ transfers = sender_wallet.get_transfers()
++ assert 'pool' not in transfers or len (transfers.pool) == 0
++ tx = [x for x in transfers.out if x.txid == txid]
++ assert len(tx) == 1
++ tx = tx[0]
++ assert sender_wallet.get_balance().balance < (sender_starting_balance - amount)
++
++ # Pop the block while background syncing
++ background_cache_password = None if background_sync_type == REUSE_PASSWORD else 'background_password'
++ sender_wallet.setup_background_sync(background_sync_type = background_sync_type, wallet_password = '', background_cache_password = background_cache_password)
++ sender_wallet.start_background_sync()
++ daemon.pop_blocks(1)
++ daemon.flush_txpool()
++
++ daemon.generateblocks('46r4nYSevkfBUMhuykdK3gQ98XDqDTYW1hNLaXNvjpsJaSbNtdXh1sKMsdVgqkaihChAzEy29zEDPMR3NHQvGoZCLGwTerK', 1)
++
++ # Make sure the wallet can no longer see the tx
++ sender_wallet.refresh()
++ sender_wallet.stop_background_sync(wallet_password = '', seed = seeds[0])
++ transfers = sender_wallet.get_transfers()
++ no_tx = [x for x in transfers.out if x.txid == txid]
++ assert len(no_tx) == 0
++ assert sender_wallet.get_balance().balance == sender_starting_balance
++
++ # Clean up
++ daemon.out_peers(12)
++ util_resources.remove_wallet_files('test1')
++ self.wallet[0].close_wallet()
++ self.wallet[0].restore_deterministic_wallet(seed = seeds[0])
++
++
+ def create(self):
+ print('Creating wallets')
+ self.wallet = [None] * len(seeds)
+@@ -840,12 +1235,6 @@ class TransferTest():
+
+ print('Testing scan_tx')
+
+- def diff_transfers(actual_transfers, expected_transfers):
+- diff = DeepDiff(actual_transfers, expected_transfers)
+- if diff != {}:
+- pp.pprint(diff)
+- assert diff == {}
+-
+ # set up sender_wallet
+ sender_wallet = self.wallet[0]
+ try: sender_wallet.close_wallet()
+diff --git a/tests/functional_tests/util_resources.py b/tests/functional_tests/util_resources.py
+index e030312da..3197187f4 100755
+--- a/tests/functional_tests/util_resources.py
++++ b/tests/functional_tests/util_resources.py
+@@ -37,6 +37,8 @@
+ from __future__ import print_function
+ import subprocess
+ import psutil
++import os
++import errno
+
+ def available_ram_gb():
+ ram_bytes = psutil.virtual_memory().available
+@@ -51,3 +53,26 @@ def get_time_pi_seconds(cores, app_dir='.'):
+ miliseconds = int(decoded)
+
+ return miliseconds / 1000.0
++
++def remove_file(name):
++ WALLET_DIRECTORY = os.environ['WALLET_DIRECTORY']
++ assert WALLET_DIRECTORY != ''
++ try:
++ os.unlink(WALLET_DIRECTORY + '/' + name)
++ except OSError as e:
++ if e.errno != errno.ENOENT:
++ raise
++
++def get_file_path(name):
++ WALLET_DIRECTORY = os.environ['WALLET_DIRECTORY']
++ assert WALLET_DIRECTORY != ''
++ return WALLET_DIRECTORY + '/' + name
++
++def remove_wallet_files(name):
++ for suffix in ['', '.keys', '.background', '.background.keys']:
++ remove_file(name + suffix)
++
++def file_exists(name):
++ WALLET_DIRECTORY = os.environ['WALLET_DIRECTORY']
++ assert WALLET_DIRECTORY != ''
++ return os.path.isfile(WALLET_DIRECTORY + '/' + name)
+diff --git a/tests/functional_tests/wallet.py b/tests/functional_tests/wallet.py
+index 1ad05c98f..8182cecb2 100755
+--- a/tests/functional_tests/wallet.py
++++ b/tests/functional_tests/wallet.py
+@@ -34,8 +34,7 @@
+
+ from __future__ import print_function
+ import sys
+-import os
+-import errno
++import util_resources
+
+ from framework.wallet import Wallet
+ from framework.daemon import Daemon
+@@ -54,24 +53,6 @@ class WalletTest():
+ self.change_password()
+ self.store()
+
+- def remove_file(self, name):
+- WALLET_DIRECTORY = os.environ['WALLET_DIRECTORY']
+- assert WALLET_DIRECTORY != ''
+- try:
+- os.unlink(WALLET_DIRECTORY + '/' + name)
+- except OSError as e:
+- if e.errno != errno.ENOENT:
+- raise
+-
+- def remove_wallet_files(self, name):
+- for suffix in ['', '.keys']:
+- self.remove_file(name + suffix)
+-
+- def file_exists(self, name):
+- WALLET_DIRECTORY = os.environ['WALLET_DIRECTORY']
+- assert WALLET_DIRECTORY != ''
+- return os.path.isfile(WALLET_DIRECTORY + '/' + name)
+-
+ def reset(self):
+ print('Resetting blockchain')
+ daemon = Daemon()
+@@ -333,7 +314,7 @@ class WalletTest():
+ try: wallet.close_wallet()
+ except: pass
+
+- self.remove_wallet_files('test1')
++ util_resources.remove_wallet_files('test1')
+
+ seed = 'velvet lymph giddy number token physics poetry unquoted nibs useful sabotage limits benches lifestyle eden nitrogen anvil fewest avoid batch vials washing fences goat unquoted'
+ res = wallet.restore_deterministic_wallet(seed = seed, filename = 'test1')
+@@ -359,7 +340,7 @@ class WalletTest():
+
+ wallet.close_wallet()
+
+- self.remove_wallet_files('test1')
++ util_resources.remove_wallet_files('test1')
+
+ def store(self):
+ print('Testing store')
+@@ -369,22 +350,26 @@ class WalletTest():
+ try: wallet.close_wallet()
+ except: pass
+
+- self.remove_wallet_files('test1')
++ util_resources.remove_wallet_files('test1')
+
+ seed = 'velvet lymph giddy number token physics poetry unquoted nibs useful sabotage limits benches lifestyle eden nitrogen anvil fewest avoid batch vials washing fences goat unquoted'
+ res = wallet.restore_deterministic_wallet(seed = seed, filename = 'test1')
+ assert res.address == '42ey1afDFnn4886T7196doS9GPMzexD9gXpsZJDwVjeRVdFCSoHnv7KPbBeGpzJBzHRCAs9UxqeoyFQMYbqSWYTfJJQAWDm'
+ assert res.seed == seed
+
+- self.remove_file('test1')
+- assert self.file_exists('test1.keys')
+- assert not self.file_exists('test1')
++ util_resources.remove_file('test1')
++ assert util_resources.file_exists('test1.keys')
++ assert not util_resources.file_exists('test1')
+ wallet.store()
+- assert self.file_exists('test1.keys')
+- assert self.file_exists('test1')
++ assert util_resources.file_exists('test1.keys')
++ assert util_resources.file_exists('test1')
+
+ wallet.close_wallet()
+- self.remove_wallet_files('test1')
++
++ wallet.open_wallet(filename = 'test1', password = '')
++ wallet.close_wallet()
++
++ util_resources.remove_wallet_files('test1')
+
+
+ if __name__ == '__main__':
+diff --git a/tests/unit_tests/wipeable_string.cpp b/tests/unit_tests/wipeable_string.cpp
+index ef6964f9e..25121a02e 100644
+--- a/tests/unit_tests/wipeable_string.cpp
++++ b/tests/unit_tests/wipeable_string.cpp
+@@ -211,3 +211,15 @@ TEST(wipeable_string, to_hex)
+ ASSERT_TRUE(epee::to_hex::wipeable_string(epee::span<const uint8_t>((const uint8_t*)"", 0)) == epee::wipeable_string(""));
+ ASSERT_TRUE(epee::to_hex::wipeable_string(epee::span<const uint8_t>((const uint8_t*)"abc", 3)) == epee::wipeable_string("616263"));
+ }
++
++TEST(wipeable_string, to_string)
++{
++ // Converting a wipeable_string to a string defeats the purpose of wipeable_string,
++ // but nice to know this works
++ std::string str;
++ {
++ epee::wipeable_string wipeable_str("foo");
++ str = std::string(wipeable_str.data(), wipeable_str.size());
++ }
++ ASSERT_TRUE(str == std::string("foo"));
++}
+diff --git a/utils/python-rpc/framework/wallet.py b/utils/python-rpc/framework/wallet.py
+index 1e10e1f86..ccf6ca93e 100644
+--- a/utils/python-rpc/framework/wallet.py
++++ b/utils/python-rpc/framework/wallet.py
+@@ -1138,3 +1138,38 @@ class Wallet(object):
+ 'id': '0'
+ }
+ return self.rpc.send_json_rpc_request(frozen)
++
++ def setup_background_sync(self, background_sync_type = 'off', wallet_password = '', background_cache_password = ''):
++ setup_background_sync = {
++ 'method': 'setup_background_sync',
++ 'jsonrpc': '2.0',
++ 'params' : {
++ 'background_sync_type': background_sync_type,
++ 'wallet_password': wallet_password,
++ 'background_cache_password': background_cache_password,
++ },
++ 'id': '0'
++ }
++ return self.rpc.send_json_rpc_request(setup_background_sync)
++
++ def start_background_sync(self):
++ start_background_sync = {
++ 'method': 'start_background_sync',
++ 'jsonrpc': '2.0',
++ 'params' : {},
++ 'id': '0'
++ }
++ return self.rpc.send_json_rpc_request(start_background_sync)
++
++ def stop_background_sync(self, wallet_password = '', seed = '', seed_offset = ''):
++ stop_background_sync = {
++ 'method': 'stop_background_sync',
++ 'jsonrpc': '2.0',
++ 'params' : {
++ 'wallet_password': wallet_password,
++ 'seed': seed,
++ 'seed_offset': seed_offset,
++ },
++ 'id': '0'
++ }
++ return self.rpc.send_json_rpc_request(stop_background_sync)