store secret keys encrypted where possible

The secret spend key is kept encrypted in memory, and
decrypted on the fly when needed.

Both spend and view secret keys are kept encrypted in a JSON
field in the keys file. This avoids leaving the keys in
memory due to being manipulated by the JSON I/O API.

tests/functional_tests/transactions_flow_test.cpp

@@ -138,7 +138,7 @@ bool transactions_flow_test(std::string& working_folder,
     return false;
   }
 
-  w1.init(daemon_addr_a);
+  w1.init(true, daemon_addr_a);
 
   uint64_t blocks_fetched = 0;
   bool received_money;
@@ -149,7 +149,7 @@ bool transactions_flow_test(std::string& working_folder,
     return false;
   }
 
-  w2.init(daemon_addr_b);
+  w2.init(true, daemon_addr_b);
 
   MGINFO_GREEN("Using wallets: " << ENDL
     << "Source:  " << w1.get_account().get_public_address_str(MAINNET) << ENDL << "Path: " << working_folder + "/" + path_source_wallet << ENDL

tests/unit_tests/CMakeLists.txt

@@ -27,6 +27,7 @@
 # THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 set(unit_tests_sources
+  account.cpp
   apply_permutation.cpp
   address_from_url.cpp
   ban.cpp

tests/unit_tests/account.cpp

@@ -0,0 +1,71 @@
+// Copyright (c) 2014-2018, The Monero Project
+// 
+// All rights reserved.
+// 
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+// 
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+// 
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+// 
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+// 
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "gtest/gtest.h"
+
+#include "cryptonote_basic/account.h"
+
+TEST(account, encrypt_keys)
+{
+  cryptonote::keypair recovery_key = cryptonote::keypair::generate(hw::get_device("default"));
+  cryptonote::account_base account;
+  crypto::secret_key key = account.generate(recovery_key.sec);
+  const cryptonote::account_keys keys = account.get_keys();
+
+  ASSERT_EQ(account.get_keys().m_account_address, keys.m_account_address);
+  ASSERT_EQ(account.get_keys().m_spend_secret_key, keys.m_spend_secret_key);
+  ASSERT_EQ(account.get_keys().m_view_secret_key, keys.m_view_secret_key);
+  ASSERT_EQ(account.get_keys().m_multisig_keys, keys.m_multisig_keys);
+
+  crypto::chacha_key chacha_key;
+  crypto::generate_chacha_key(&recovery_key, sizeof(recovery_key), chacha_key, 1);
+
+  account.encrypt_keys(chacha_key);
+
+  ASSERT_EQ(account.get_keys().m_account_address, keys.m_account_address);
+  ASSERT_NE(account.get_keys().m_spend_secret_key, keys.m_spend_secret_key);
+  ASSERT_NE(account.get_keys().m_view_secret_key, keys.m_view_secret_key);
+
+  account.decrypt_viewkey(chacha_key);
+
+  ASSERT_EQ(account.get_keys().m_account_address, keys.m_account_address);
+  ASSERT_NE(account.get_keys().m_spend_secret_key, keys.m_spend_secret_key);
+  ASSERT_EQ(account.get_keys().m_view_secret_key, keys.m_view_secret_key);
+
+  account.encrypt_viewkey(chacha_key);
+
+  ASSERT_EQ(account.get_keys().m_account_address, keys.m_account_address);
+  ASSERT_NE(account.get_keys().m_spend_secret_key, keys.m_spend_secret_key);
+  ASSERT_NE(account.get_keys().m_view_secret_key, keys.m_view_secret_key);
+
+  account.decrypt_keys(chacha_key);
+
+  ASSERT_EQ(account.get_keys().m_account_address, keys.m_account_address);
+  ASSERT_EQ(account.get_keys().m_spend_secret_key, keys.m_spend_secret_key);
+  ASSERT_EQ(account.get_keys().m_view_secret_key, keys.m_view_secret_key);
+}

tests/unit_tests/multisig.cpp

@@ -61,10 +61,13 @@ static void make_wallet(unsigned int idx, tools::wallet2 &wallet)
 
   try
   {
-    wallet.init("");
+    wallet.init(false, "");
     wallet.set_subaddress_lookahead(1, 1);
     wallet.generate("", "", spendkey, true, false);
     ASSERT_TRUE(test_addresses[idx].address == wallet.get_account().get_public_address_str(cryptonote::TESTNET));
+    wallet.decrypt_keys("");
+    ASSERT_TRUE(test_addresses[idx].spendkey == epee::string_tools::pod_to_hex(wallet.get_account().get_keys().m_spend_secret_key));
+    wallet.encrypt_keys("");
   }
   catch (const std::exception &e)
   {
@@ -83,8 +86,12 @@ static void make_M_2_wallet(tools::wallet2 &wallet0, tools::wallet2 &wallet1, un
   std::vector<crypto::secret_key> sk0(1), sk1(1);
   std::vector<crypto::public_key> pk0(1), pk1(1);
 
+  wallet0.decrypt_keys("");
   std::string mi0 = wallet0.get_multisig_info();
+  wallet0.encrypt_keys("");
+  wallet1.decrypt_keys("");
   std::string mi1 = wallet1.get_multisig_info();
+  wallet1.encrypt_keys("");
 
   ASSERT_TRUE(tools::wallet2::verify_multisig_info(mi1, sk0[0], pk0[0]));
   ASSERT_TRUE(tools::wallet2::verify_multisig_info(mi0, sk1[0], pk1[0]));
@@ -118,9 +125,15 @@ static void make_M_3_wallet(tools::wallet2 &wallet0, tools::wallet2 &wallet1, to
   std::vector<crypto::secret_key> sk0(2), sk1(2), sk2(2);
   std::vector<crypto::public_key> pk0(2), pk1(2), pk2(2);
 
+  wallet0.decrypt_keys("");
   std::string mi0 = wallet0.get_multisig_info();
+  wallet0.encrypt_keys("");
+  wallet1.decrypt_keys("");
   std::string mi1 = wallet1.get_multisig_info();
+  wallet1.encrypt_keys("");
+  wallet2.decrypt_keys("");
   std::string mi2 = wallet2.get_multisig_info();
+  wallet2.encrypt_keys("");
 
   ASSERT_TRUE(tools::wallet2::verify_multisig_info(mi1, sk0[0], pk0[0]));
   ASSERT_TRUE(tools::wallet2::verify_multisig_info(mi2, sk0[1], pk0[1]));

tests/unit_tests/ringdb.cpp

@@ -47,7 +47,7 @@ static crypto::chacha_key generate_chacha_key()
 {
   crypto::chacha_key chacha_key;
   uint64_t password = crypto::rand<uint64_t>();
-  crypto::generate_chacha_key(std::string((const char*)&password, sizeof(password)), chacha_key);
+  crypto::generate_chacha_key(std::string((const char*)&password, sizeof(password)), chacha_key, 1);
   return chacha_key;
 }