This check is excessive since we don't support walletless mode for now.

[novacoin.git] / src / crypter.cpp

diff --git a/src/crypter.cpp b/src/crypter.cpp
index 2a6f36d..ae2b0f4 100644 (file)
--- a/src/crypter.cpp
+++ b/src/crypter.cpp
@@ -13,6 +13,23 @@
 #include <windows.h>
 #endif
 
+//
+//CMasterKey
+//
+
+CMasterKey::CMasterKey()
+{
+    // 25000 rounds is just under 0.1 seconds on a 1.86 GHz Pentium M
+    // ie slightly lower than the lowest hardware we need bother supporting
+    nDeriveIterations = 25000;
+    nDerivationMethod = 0;
+    vchOtherDerivationParameters = std::vector<unsigned char>(0);
+}
+
+//
+//CCrypter
+//
+
 bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod)
 {
     if (nRounds < 1 || chSalt.size() != WALLET_CRYPTO_SALT_SIZE)
@@ -22,7 +39,7 @@ bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const std::v
     if (nDerivationMethod == 0)
     {
         i = EVP_BytesToKey(EVP_aes_256_cbc(), EVP_sha512(), &chSalt[0],
-                          (unsigned char *)&strKeyData[0], strKeyData.size(), nRounds, chKey, chIV);
+                          (const unsigned char *)&strKeyData[0], strKeyData.size(), nRounds, chKey, chIV);
     }
 
     if (i != (int)WALLET_CRYPTO_KEY_SIZE)
@@ -102,6 +119,31 @@ bool CCrypter::Decrypt(const std::vector<unsigned char>& vchCiphertext, CKeyingM
     return true;
 }
 
+void CCrypter::CleanKey()
+{
+    OPENSSL_cleanse(&chKey, sizeof chKey);
+    OPENSSL_cleanse(&chIV, sizeof chIV);
+    fKeySet = false;
+}
+
+CCrypter::CCrypter()
+{
+    fKeySet = false;
+
+    // Try to keep the key data out of swap (and be a bit over-careful to keep the IV that we don't even use out of swap)
+    // Note that this does nothing about suspend-to-disk (which will put all our key data on disk)
+    // Note as well that at no point in this program is any attempt made to prevent stealing of keys by reading the memory of the running process.
+    LockedPageManager::instance.LockRange(&chKey[0], sizeof chKey);
+    LockedPageManager::instance.LockRange(&chIV[0], sizeof chIV);
+}
+
+CCrypter::~CCrypter()
+{
+    CleanKey();
+
+    LockedPageManager::instance.UnlockRange(&chKey[0], sizeof chKey);
+    LockedPageManager::instance.UnlockRange(&chIV[0], sizeof chIV);
+}
 
 bool EncryptSecret(CKeyingMaterial& vMasterKey, const CSecret &vchPlaintext, const uint256& nIV, std::vector<unsigned char> &vchCiphertext)
 {