wallet: allow adjusting number of rounds for the key derivation function

14 files changed, 76 insertions, 52 deletions

diff --git a/src/crypto/chacha.h b/src/crypto/chacha.h
index 2b3ed8043..1dc270faf 100644
--- a/src/crypto/chacha.h
+++ b/src/crypto/chacha.h
@@ -69,22 +69,26 @@ namespace crypto {
     chacha20(data, length, key.data(), reinterpret_cast<const uint8_t*>(&iv), cipher);
   }
 
-  inline void generate_chacha_key(const void *data, size_t size, chacha_key& key) {
+  inline void generate_chacha_key(const void *data, size_t size, chacha_key& key, uint64_t kdf_rounds) {
     static_assert(sizeof(chacha_key) <= sizeof(hash), "Size of hash must be at least that of chacha_key");
     tools::scrubbed_arr<char, HASH_SIZE> pwd_hash;
     crypto::cn_slow_hash(data, size, pwd_hash.data(), 0/*variant*/, 0/*prehashed*/);
+    for (uint64_t n = 1; n < kdf_rounds; ++n)
+      crypto::cn_slow_hash(pwd_hash.data(), pwd_hash.size(), pwd_hash.data(), 0/*variant*/, 0/*prehashed*/);
     memcpy(&unwrap(key), pwd_hash.data(), sizeof(key));
   }
 
-  inline void generate_chacha_key_prehashed(const void *data, size_t size, chacha_key& key) {
+  inline void generate_chacha_key_prehashed(const void *data, size_t size, chacha_key& key, uint64_t kdf_rounds) {
     static_assert(sizeof(chacha_key) <= sizeof(hash), "Size of hash must be at least that of chacha_key");
     tools::scrubbed_arr<char, HASH_SIZE> pwd_hash;
     crypto::cn_slow_hash(data, size, pwd_hash.data(), 0/*variant*/, 1/*prehashed*/);
+    for (uint64_t n = 1; n < kdf_rounds; ++n)
+      crypto::cn_slow_hash(pwd_hash.data(), pwd_hash.size(), pwd_hash.data(), 0/*variant*/, 0/*prehashed*/);
     memcpy(&unwrap(key), pwd_hash.data(), sizeof(key));
   }
 
-  inline void generate_chacha_key(std::string password, chacha_key& key) {
-    return generate_chacha_key(password.data(), password.size(), key);
+  inline void generate_chacha_key(std::string password, chacha_key& key, uint64_t kdf_rounds) {
+    return generate_chacha_key(password.data(), password.size(), key, kdf_rounds);
   }
 }
 
diff --git a/src/device/device.hpp b/src/device/device.hpp
index 9df0cb39d..c21456daf 100644
--- a/src/device/device.hpp
+++ b/src/device/device.hpp
@@ -125,7 +125,7 @@ namespace hw {
         /* ======================================================================= */
         virtual bool  get_public_address(cryptonote::account_public_address &pubkey) = 0;
         virtual bool  get_secret_keys(crypto::secret_key &viewkey , crypto::secret_key &spendkey)  = 0;
-        virtual bool  generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key) = 0;
+        virtual bool  generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key, uint64_t kdf_rounds) = 0;
 
         /* ======================================================================= */
         /*                               SUB ADDRESS                               */
diff --git a/src/device/device_default.cpp b/src/device/device_default.cpp
index 0071f7d4f..bf14813ea 100644
--- a/src/device/device_default.cpp
+++ b/src/device/device_default.cpp
@@ -100,14 +100,14 @@ namespace hw {
         /*                             WALLET & ADDRESS                            */
         /* ======================================================================= */
 
-        bool  device_default::generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key) {
+        bool  device_default::generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key, uint64_t kdf_rounds) {
             const crypto::secret_key &view_key = keys.m_view_secret_key;
             const crypto::secret_key &spend_key = keys.m_spend_secret_key;
             tools::scrubbed_arr<char, sizeof(view_key) + sizeof(spend_key) + 1> data;
             memcpy(data.data(), &view_key, sizeof(view_key));
             memcpy(data.data() + sizeof(view_key), &spend_key, sizeof(spend_key));
             data[sizeof(data) - 1] = CHACHA8_KEY_TAIL;
-            crypto::generate_chacha_key(data.data(), sizeof(data), key);
+            crypto::generate_chacha_key(data.data(), sizeof(data), key, kdf_rounds);
             return true;
         }
         bool  device_default::get_public_address(cryptonote::account_public_address &pubkey) {
diff --git a/src/device/device_default.hpp b/src/device/device_default.hpp
index 771fbba72..8d841d9de 100644
--- a/src/device/device_default.hpp
+++ b/src/device/device_default.hpp
@@ -73,7 +73,7 @@ namespace hw {
             /* ======================================================================= */
             bool  get_public_address(cryptonote::account_public_address &pubkey) override;
             bool  get_secret_keys(crypto::secret_key &viewkey , crypto::secret_key &spendkey) override;
-            bool  generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key) override;
+            bool  generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key, uint64_t kdf_rounds) override;
  
             /* ======================================================================= */
             /*                               SUB ADDRESS                               */
diff --git a/src/device/device_ledger.cpp b/src/device/device_ledger.cpp
index f7bf58531..7a34dad5e 100644
--- a/src/device/device_ledger.cpp
+++ b/src/device/device_ledger.cpp
@@ -531,20 +531,20 @@ namespace hw {
         return true;
     }
 
-    bool  device_ledger::generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key) {
+    bool  device_ledger::generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key, uint64_t kdf_rounds) {
         AUTO_LOCK_CMD();
 
         #ifdef DEBUG_HWDEVICE
         crypto::chacha_key key_x;
         cryptonote::account_keys keys_x = hw::ledger::decrypt(keys); 
-        this->controle_device->generate_chacha_key(keys_x, key_x);
+        this->controle_device->generate_chacha_key(keys_x, key_x, kdf_rounds);
         #endif
 
         send_simple(INS_GET_CHACHA8_PREKEY);
 
         char prekey[200];
         memmove(prekey, &this->buffer_recv[0], 200);
-        crypto::generate_chacha_key_prehashed(&prekey[0], sizeof(prekey), key);
+        crypto::generate_chacha_key_prehashed(&prekey[0], sizeof(prekey), key, kdf_rounds);
 
         #ifdef DEBUG_HWDEVICE
         hw::ledger::check32("generate_chacha_key_prehashed", "key", (char*)key_x.data(), (char*)key.data());
diff --git a/src/device/device_ledger.hpp b/src/device/device_ledger.hpp
index c30a38aca..e6c6e5b52 100644
--- a/src/device/device_ledger.hpp
+++ b/src/device/device_ledger.hpp
@@ -156,7 +156,7 @@ namespace hw {
         /* ======================================================================= */
         bool  get_public_address(cryptonote::account_public_address &pubkey) override;
         bool  get_secret_keys(crypto::secret_key &viewkey , crypto::secret_key &spendkey) override;
-        bool  generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key) override;
+        bool  generate_chacha_key(const cryptonote::account_keys &keys, crypto::chacha_key &key, uint64_t kdf_rounds) override;
 
 
         /* ======================================================================= */
diff --git a/src/wallet/api/wallet.cpp b/src/wallet/api/wallet.cpp
index 680da26ce..f7c074b5a 100644
--- a/src/wallet/api/wallet.cpp
+++ b/src/wallet/api/wallet.cpp
@@ -366,7 +366,7 @@ void Wallet::error(const std::string &category, const std::string &str) {
 }
 
 ///////////////////////// WalletImpl implementation ////////////////////////
-WalletImpl::WalletImpl(NetworkType nettype)
+WalletImpl::WalletImpl(NetworkType nettype, bool restricted, uint64_t kdf_rounds)
     :m_wallet(nullptr)
     , m_status(Wallet::Status_Ok)
     , m_trustedDaemon(false)
@@ -377,7 +377,7 @@ WalletImpl::WalletImpl(NetworkType nettype)
     , m_rebuildWalletCache(false)
     , m_is_connected(false)
 {
-    m_wallet = new tools::wallet2(static_cast<cryptonote::network_type>(nettype));
+    m_wallet = new tools::wallet2(static_cast<cryptonote::network_type>(nettype), restricted, kdf_rounds);
     m_history = new TransactionHistoryImpl(this);
     m_wallet2Callback = new Wallet2CallbackImpl(this);
     m_wallet->callback(m_wallet2Callback);
diff --git a/src/wallet/api/wallet.h b/src/wallet/api/wallet.h
index 58be686fc..28b73423d 100644
--- a/src/wallet/api/wallet.h
+++ b/src/wallet/api/wallet.h
@@ -52,7 +52,7 @@ struct Wallet2CallbackImpl;
 class WalletImpl : public Wallet
 {
 public:
-    WalletImpl(NetworkType nettype = MAINNET);
+    WalletImpl(NetworkType nettype = MAINNET, bool restricted = false, uint64_t kdf_rounds = 1);
     ~WalletImpl();
     bool create(const std::string &path, const std::string &password,
                 const std::string &language);
diff --git a/src/wallet/api/wallet2_api.h b/src/wallet/api/wallet2_api.h
index 0cd0ff5cf..5a52c6b17 100644
--- a/src/wallet/api/wallet2_api.h
+++ b/src/wallet/api/wallet2_api.h
@@ -920,9 +920,10 @@ struct WalletManager
      * \param  password       Password of wallet file
      * \param  language       Language to be used to generate electrum seed mnemonic
      * \param  nettype        Network type
+     * \param  kdf_rounds     Number of rounds for key derivation function
      * \return                Wallet instance (Wallet::status() needs to be called to check if created successfully)
      */
-    virtual Wallet * createWallet(const std::string &path, const std::string &password, const std::string &language, NetworkType nettype) = 0;
+    virtual Wallet * createWallet(const std::string &path, const std::string &password, const std::string &language, NetworkType nettype, uint64_t kdf_rounds = 1) = 0;
     Wallet * createWallet(const std::string &path, const std::string &password, const std::string &language, bool testnet = false)      // deprecated
     {
         return createWallet(path, password, language, testnet ? TESTNET : MAINNET);
@@ -933,9 +934,10 @@ struct WalletManager
      * \param  path           Name of wallet file
      * \param  password       Password of wallet file
      * \param  nettype        Network type
+     * \param  kdf_rounds     Number of rounds for key derivation function
      * \return                Wallet instance (Wallet::status() needs to be called to check if opened successfully)
      */
-    virtual Wallet * openWallet(const std::string &path, const std::string &password, NetworkType nettype) = 0;
+    virtual Wallet * openWallet(const std::string &path, const std::string &password, NetworkType nettype, uint64_t kdf_rounds = 1) = 0;
     Wallet * openWallet(const std::string &path, const std::string &password, bool testnet = false)     // deprecated
     {
         return openWallet(path, password, testnet ? TESTNET : MAINNET);
@@ -948,10 +950,11 @@ struct WalletManager
      * \param  mnemonic       mnemonic (25 words electrum seed)
      * \param  nettype        Network type
      * \param  restoreHeight  restore from start height
+     * \param  kdf_rounds     Number of rounds for key derivation function
      * \return                Wallet instance (Wallet::status() needs to be called to check if recovered successfully)
      */
     virtual Wallet * recoveryWallet(const std::string &path, const std::string &password, const std::string &mnemonic,
-                                    NetworkType nettype = MAINNET, uint64_t restoreHeight = 0) = 0;
+                                    NetworkType nettype = MAINNET, uint64_t restoreHeight = 0, uint64_t kdf_rounds = 1) = 0;
     Wallet * recoveryWallet(const std::string &path, const std::string &password, const std::string &mnemonic,
                                     bool testnet = false, uint64_t restoreHeight = 0)           // deprecated
     {
@@ -983,6 +986,7 @@ struct WalletManager
      * \param  addressString  public address
      * \param  viewKeyString  view key
      * \param  spendKeyString spend key (optional)
+     * \param  kdf_rounds     Number of rounds for key derivation function
      * \return                Wallet instance (Wallet::status() needs to be called to check if recovered successfully)
      */
     virtual Wallet * createWalletFromKeys(const std::string &path,
@@ -992,7 +996,8 @@ struct WalletManager
                                                     uint64_t restoreHeight,
                                                     const std::string &addressString,
                                                     const std::string &viewKeyString,
-                                                    const std::string &spendKeyString = "") = 0;
+                                                    const std::string &spendKeyString = "",
+                                                    uint64_t kdf_rounds = 1) = 0;
     Wallet * createWalletFromKeys(const std::string &path,
                                   const std::string &password,
                                   const std::string &language,
@@ -1043,6 +1048,7 @@ struct WalletManager
      * \param  deviceName           Device name
      * \param  restoreHeight        restore from start height (0 sets to current height)
      * \param  subaddressLookahead  Size of subaddress lookahead (empty sets to some default low value)
+     * \param  kdf_rounds           Number of rounds for key derivation function
      * \return                      Wallet instance (Wallet::status() needs to be called to check if recovered successfully)
      */
     virtual Wallet * createWalletFromDevice(const std::string &path,
@@ -1050,7 +1056,8 @@ struct WalletManager
                                             NetworkType nettype,
                                             const std::string &deviceName,
                                             uint64_t restoreHeight = 0,
-                                            const std::string &subaddressLookahead = "") = 0;
+                                            const std::string &subaddressLookahead = "",
+                                            uint64_t kdf_rounds = 1) = 0;
 
     /*!
      * \brief Closes wallet. In case operation succeeded, wallet object deleted. in case operation failed, wallet object not deleted
@@ -1075,13 +1082,14 @@ struct WalletManager
      * @param keys_file_name - location of keys file
      * @param password - password to verify
      * @param no_spend_key - verify only view keys?
+     * @param kdf_rounds - number of rounds for key derivation function
      * @return - true if password is correct
      *
      * @note
      * This function will fail when the wallet keys file is opened because the wallet program locks the keys file.
      * In this case, Wallet::unlockKeysFile() and Wallet::lockKeysFile() need to be called before and after the call to this function, respectively.
      */
-    virtual bool verifyWalletPassword(const std::string &keys_file_name, const std::string &password, bool no_spend_key) const = 0;
+    virtual bool verifyWalletPassword(const std::string &keys_file_name, const std::string &password, bool no_spend_key, uint64_t kdf_rounds = 1) const = 0;
 
     /*!
      * \brief findWallets - searches for the wallet files by given path name recursively
diff --git a/src/wallet/api/wallet_manager.cpp b/src/wallet/api/wallet_manager.cpp
index 99eadc82f..5daf11ec0 100644
--- a/src/wallet/api/wallet_manager.cpp
+++ b/src/wallet/api/wallet_manager.cpp
@@ -50,16 +50,16 @@ namespace epee {
 namespace Monero {
 
 Wallet *WalletManagerImpl::createWallet(const std::string &path, const std::string &password,
-                                    const std::string &language, NetworkType nettype)
+                                    const std::string &language, NetworkType nettype, uint64_t kdf_rounds)
 {
-    WalletImpl * wallet = new WalletImpl(nettype);
+    WalletImpl * wallet = new WalletImpl(nettype, false, kdf_rounds);
     wallet->create(path, password, language);
     return wallet;
 }
 
-Wallet *WalletManagerImpl::openWallet(const std::string &path, const std::string &password, NetworkType nettype)
+Wallet *WalletManagerImpl::openWallet(const std::string &path, const std::string &password, NetworkType nettype, uint64_t kdf_rounds)
 {
-    WalletImpl * wallet = new WalletImpl(nettype);
+    WalletImpl * wallet = new WalletImpl(nettype, false, kdf_rounds);
     wallet->open(path, password);
     //Refresh addressBook
     wallet->addressBook()->refresh(); 
@@ -87,9 +87,10 @@ Wallet *WalletManagerImpl::recoveryWallet(const std::string &path,
                                                 const std::string &password,
                                                 const std::string &mnemonic,
                                                 NetworkType nettype,
-                                                uint64_t restoreHeight)
+                                                uint64_t restoreHeight,
+                                                uint64_t kdf_rounds)
 {
-    WalletImpl * wallet = new WalletImpl(nettype);
+    WalletImpl * wallet = new WalletImpl(nettype, false, kdf_rounds);
     if(restoreHeight > 0){
         wallet->setRefreshFromBlockHeight(restoreHeight);
     }
@@ -104,9 +105,10 @@ Wallet *WalletManagerImpl::createWalletFromKeys(const std::string &path,
                                                 uint64_t restoreHeight,
                                                 const std::string &addressString,
                                                 const std::string &viewKeyString,
-                                                const std::string &spendKeyString)
+                                                const std::string &spendKeyString,
+                                                uint64_t kdf_rounds)
 {
-    WalletImpl * wallet = new WalletImpl(nettype);
+    WalletImpl * wallet = new WalletImpl(nettype, false, kdf_rounds);
     if(restoreHeight > 0){
         wallet->setRefreshFromBlockHeight(restoreHeight);
     }
@@ -119,9 +121,10 @@ Wallet *WalletManagerImpl::createWalletFromDevice(const std::string &path,
                                                   NetworkType nettype,
                                                   const std::string &deviceName,
                                                   uint64_t restoreHeight,
-                                                  const std::string &subaddressLookahead)
+                                                  const std::string &subaddressLookahead,
+                                                  uint64_t kdf_rounds)
 {
-    WalletImpl * wallet = new WalletImpl(nettype);
+    WalletImpl * wallet = new WalletImpl(nettype, false, kdf_rounds);
     if(restoreHeight > 0){
         wallet->setRefreshFromBlockHeight(restoreHeight);
     }
@@ -159,9 +162,9 @@ bool WalletManagerImpl::walletExists(const std::string &path)
     return false;
 }
 
-bool WalletManagerImpl::verifyWalletPassword(const std::string &keys_file_name, const std::string &password, bool no_spend_key) const
+bool WalletManagerImpl::verifyWalletPassword(const std::string &keys_file_name, const std::string &password, bool no_spend_key, uint64_t kdf_rounds) const
 {
-	    return tools::wallet2::verify_password(keys_file_name, password, no_spend_key, hw::get_device("default"));
+	    return tools::wallet2::verify_password(keys_file_name, password, no_spend_key, hw::get_device("default"), kdf_rounds);
 }
 
 std::vector<std::string> WalletManagerImpl::findWallets(const std::string &path)
diff --git a/src/wallet/api/wallet_manager.h b/src/wallet/api/wallet_manager.h
index 656a7142c..8b1c8be7f 100644
--- a/src/wallet/api/wallet_manager.h
+++ b/src/wallet/api/wallet_manager.h
@@ -39,13 +39,14 @@ class WalletManagerImpl : public WalletManager
 {
 public:
     Wallet * createWallet(const std::string &path, const std::string &password,
-                          const std::string &language, NetworkType nettype) override;
-    Wallet * openWallet(const std::string &path, const std::string &password, NetworkType nettype) override;
+                          const std::string &language, NetworkType nettype, uint64_t kdf_rounds = 1) override;
+    Wallet * openWallet(const std::string &path, const std::string &password, NetworkType nettype, uint64_t kdf_rounds = 1) override;
     virtual Wallet * recoveryWallet(const std::string &path,
                                        const std::string &password,
                                        const std::string &mnemonic,
                                        NetworkType nettype,
-                                       uint64_t restoreHeight) override;
+                                       uint64_t restoreHeight,
+                                       uint64_t kdf_rounds = 1) override;
     virtual Wallet * createWalletFromKeys(const std::string &path,
                                              const std::string &password,
                                              const std::string &language,
@@ -53,7 +54,8 @@ public:
                                              uint64_t restoreHeight,
                                              const std::string &addressString,
                                              const std::string &viewKeyString,
-                                             const std::string &spendKeyString = "") override;
+                                             const std::string &spendKeyString = "",
+                                             uint64_t kdf_rounds = 1) override;
     // next two methods are deprecated - use the above version which allow setting of a password
     virtual Wallet * recoveryWallet(const std::string &path, const std::string &mnemonic, NetworkType nettype, uint64_t restoreHeight) override;
     // deprecated: use createWalletFromKeys(..., password, ...) instead
@@ -69,10 +71,11 @@ public:
                                             NetworkType nettype,
                                             const std::string &deviceName,
                                             uint64_t restoreHeight = 0,
-                                            const std::string &subaddressLookahead = "") override;
+                                            const std::string &subaddressLookahead = "",
+                                            uint64_t kdf_rounds = 1) override;
     virtual bool closeWallet(Wallet *wallet, bool store = true) override;
     bool walletExists(const std::string &path) override;
-    bool verifyWalletPassword(const std::string &keys_file_name, const std::string &password, bool no_spend_key) const override;
+    bool verifyWalletPassword(const std::string &keys_file_name, const std::string &password, bool no_spend_key, uint64_t kdf_rounds = 1) const override;
     std::vector<std::string> findWallets(const std::string &path) override;
     std::string errorString() const override;
     void setDaemonAddress(const std::string &address) override;
diff --git a/src/wallet/wallet2.cpp b/src/wallet/wallet2.cpp
index 90807803a..439bacd17 100644
--- a/src/wallet/wallet2.cpp
+++ b/src/wallet/wallet2.cpp
@@ -160,6 +160,7 @@ struct options {
       return val;
     }
   };
+  const command_line::arg_descriptor<uint64_t> kdf_rounds = {"kdf-rounds", tools::wallet2::tr("Number of rounds for the key derivation function"), 1};
 };
 
 void do_prepare_file_names(const std::string& file_path, std::string& keys_file, std::string& wallet_file)
@@ -203,6 +204,8 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   const bool stagenet = command_line::get_arg(vm, opts.stagenet);
   const network_type nettype = testnet ? TESTNET : stagenet ? STAGENET : MAINNET;
   const bool restricted = command_line::get_arg(vm, opts.restricted);
+  const uint64_t kdf_rounds = command_line::get_arg(vm, opts.kdf_rounds);
+  THROW_WALLET_EXCEPTION_IF(kdf_rounds == 0, tools::error::wallet_internal_error, "KDF rounds must not be 0");
 
   auto daemon_address = command_line::get_arg(vm, opts.daemon_address);
   auto daemon_host = command_line::get_arg(vm, opts.daemon_host);
@@ -236,7 +239,7 @@ std::unique_ptr<tools::wallet2> make_basic(const boost::program_options::variabl
   if (daemon_address.empty())
     daemon_address = std::string("http://") + daemon_host + ":" + std::to_string(daemon_port);
 
-  std::unique_ptr<tools::wallet2> wallet(new tools::wallet2(nettype, restricted));
+  std::unique_ptr<tools::wallet2> wallet(new tools::wallet2(nettype, restricted, kdf_rounds));
   wallet->init(std::move(daemon_address), std::move(login));
   boost::filesystem::path ringdb_path = command_line::get_arg(vm, opts.shared_ringdb_dir);
   wallet->set_ring_database(ringdb_path.string());
@@ -647,7 +650,7 @@ const size_t MAX_SPLIT_ATTEMPTS = 30;
 constexpr const std::chrono::seconds wallet2::rpc_timeout;
 const char* wallet2::tr(const char* str) { return i18n_translate(str, "tools::wallet2"); }
 
-wallet2::wallet2(network_type nettype, bool restricted):
+wallet2::wallet2(network_type nettype, bool restricted, uint64_t kdf_rounds):
   m_multisig_rescan_info(NULL),
   m_multisig_rescan_k(NULL),
   m_run(true),
@@ -679,6 +682,7 @@ wallet2::wallet2(network_type nettype, bool restricted):
   m_ignore_fractional_outputs(true),
   m_is_initialized(false),
   m_restricted(restricted),
+  m_kdf_rounds(kdf_rounds),
   is_old_file_format(false),
   m_node_rpc_proxy(m_http_client, m_daemon_rpc_mutex),
   m_subaddress_lookahead_major(SUBADDRESS_LOOKAHEAD_MAJOR),
@@ -723,6 +727,7 @@ void wallet2::init_options(boost::program_options::options_description& desc_par
   command_line::add_arg(desc_params, opts.stagenet);
   command_line::add_arg(desc_params, opts.restricted);
   command_line::add_arg(desc_params, opts.shared_ringdb_dir);
+  command_line::add_arg(desc_params, opts.kdf_rounds);
 }
 
 std::unique_ptr<wallet2> wallet2::make_from_json(const boost::program_options::variables_map& vm, const std::string& json_file, const std::function<boost::optional<tools::password_container>(const char *, bool)> &password_prompter)
@@ -2844,7 +2849,7 @@ bool wallet2::store_keys(const std::string& keys_file_name, const epee::wipeable
 
   // Encrypt the entire JSON object.
   crypto::chacha_key key;
-  crypto::generate_chacha_key(password.data(), password.size(), key);
+  crypto::generate_chacha_key(password.data(), password.size(), key, m_kdf_rounds);
   std::string cipher;
   cipher.resize(account_data.size());
   keys_file_data.iv = crypto::rand<crypto::chacha_iv>();
@@ -2878,7 +2883,7 @@ bool wallet2::load_keys(const std::string& keys_file_name, const epee::wipeable_
   r = ::serialization::parse_binary(buf, keys_file_data);
   THROW_WALLET_EXCEPTION_IF(!r, error::wallet_internal_error, "internal error: failed to deserialize \"" + keys_file_name + '\"');
   crypto::chacha_key key;
-  crypto::generate_chacha_key(password.data(), password.size(), key);
+  crypto::generate_chacha_key(password.data(), password.size(), key, m_kdf_rounds);
   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]);
@@ -3084,7 +3089,7 @@ bool wallet2::verify_password(const epee::wipeable_string& password)
 {
   // 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_watch_only || m_multisig, m_account.get_device());
+  bool r = verify_password(m_keys_file, password, m_watch_only || m_multisig, m_account.get_device(), m_kdf_rounds);
   lock_keys_file();
   return r;
 }
@@ -3102,7 +3107,7 @@ 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)
+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)
 {
   rapidjson::Document json;
   wallet2::keys_file_data keys_file_data;
@@ -3114,7 +3119,7 @@ bool wallet2::verify_password(const std::string& keys_file_name, const epee::wip
   r = ::serialization::parse_binary(buf, keys_file_data);
   THROW_WALLET_EXCEPTION_IF(!r, error::wallet_internal_error, "internal error: failed to deserialize \"" + keys_file_name + '\"');
   crypto::chacha_key key;
-  crypto::generate_chacha_key(password.data(), password.size(), key);
+  crypto::generate_chacha_key(password.data(), password.size(), key, kdf_rounds);
   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]);
@@ -3982,7 +3987,7 @@ bool wallet2::check_connection(uint32_t *version, uint32_t timeout)
 bool wallet2::generate_chacha_key_from_secret_keys(crypto::chacha_key &key) const
 {
   hw::device &hwdev =  m_account.get_device();
-  return hwdev.generate_chacha_key(m_account.get_keys(), key);
+  return hwdev.generate_chacha_key(m_account.get_keys(), key, m_kdf_rounds);
 }
 //----------------------------------------------------------------------------------------------------
 void wallet2::load(const std::string& wallet_, const epee::wipeable_string& password)
@@ -10534,7 +10539,7 @@ size_t wallet2::import_multisig(std::vector<cryptonote::blobdata> blobs)
 std::string wallet2::encrypt(const std::string &plaintext, const crypto::secret_key &skey, bool authenticated) const
 {
   crypto::chacha_key key;
-  crypto::generate_chacha_key(&skey, sizeof(skey), key);
+  crypto::generate_chacha_key(&skey, sizeof(skey), key, m_kdf_rounds);
   std::string ciphertext;
   crypto::chacha_iv iv = crypto::rand<crypto::chacha_iv>();
   ciphertext.resize(plaintext.size() + sizeof(iv) + (authenticated ? sizeof(crypto::signature) : 0));
@@ -10564,7 +10569,7 @@ std::string wallet2::decrypt(const std::string &ciphertext, const crypto::secret
     error::wallet_internal_error, "Unexpected ciphertext size");
 
   crypto::chacha_key key;
-  crypto::generate_chacha_key(&skey, sizeof(skey), key);
+  crypto::generate_chacha_key(&skey, sizeof(skey), key, m_kdf_rounds);
   const crypto::chacha_iv &iv = *(const crypto::chacha_iv*)&ciphertext[0];
   std::string plaintext;
   plaintext.resize(ciphertext.size() - prefix_size);
diff --git a/src/wallet/wallet2.h b/src/wallet/wallet2.h
index 220eca8a8..e2c192084 100644
--- a/src/wallet/wallet2.h
+++ b/src/wallet/wallet2.h
@@ -165,9 +165,9 @@ namespace tools
     //! Just parses variables.
     static std::unique_ptr<wallet2> make_dummy(const boost::program_options::variables_map& vm, 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);
+    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);
 
-    wallet2(cryptonote::network_type nettype = cryptonote::MAINNET, bool restricted = false);
+    wallet2(cryptonote::network_type nettype = cryptonote::MAINNET, bool restricted = false, uint64_t kdf_rounds = 1);
     ~wallet2();
 
     struct multisig_info
@@ -1258,6 +1258,7 @@ namespace tools
     bool m_key_on_device;
     cryptonote::network_type m_nettype;
     bool m_restricted;
+    uint64_t m_kdf_rounds;
     std::string seed_language; /*!< Language of the mnemonics (seed). */
     bool is_old_file_format; /*!< Whether the wallet file is of an old file format */
     bool m_watch_only; /*!< no spend key */
diff --git a/tests/unit_tests/serialization.cpp b/tests/unit_tests/serialization.cpp
index 5a2114027..40616059a 100644
--- a/tests/unit_tests/serialization.cpp
+++ b/tests/unit_tests/serialization.cpp
@@ -810,7 +810,7 @@ TEST(Serialization, portability_outputs)
     if(ciphertext.size() < prefix_size)
       return {};
     crypto::chacha_key key;
-    crypto::generate_chacha_key(&skey, sizeof(skey), key);
+    crypto::generate_chacha_key(&skey, sizeof(skey), key, 1);
     const crypto::chacha_iv &iv = *(const crypto::chacha_iv*)&ciphertext[0];
     std::string plaintext;
     plaintext.resize(ciphertext.size() - prefix_size);