Initial Vexta Core v0.1.0 release

src/wallet/crypter.h

@@ -0,0 +1,110 @@
+// Copyright (c) 2009-2020 The Bitcoin Core developers
+// Copyright (c) 2014-2020 The DigiByte Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef DIGIBYTE_WALLET_CRYPTER_H
+#define DIGIBYTE_WALLET_CRYPTER_H
+
+#include <serialize.h>
+#include <support/allocators/secure.h>
+#include <script/signingprovider.h>
+
+
+const unsigned int WALLET_CRYPTO_KEY_SIZE = 32;
+const unsigned int WALLET_CRYPTO_SALT_SIZE = 8;
+const unsigned int WALLET_CRYPTO_IV_SIZE = 16;
+
+/**
+ * Private key encryption is done based on a CMasterKey,
+ * which holds a salt and random encryption key.
+ *
+ * CMasterKeys are encrypted using AES-256-CBC using a key
+ * derived using derivation method nDerivationMethod
+ * (0 == EVP_sha512()) and derivation iterations nDeriveIterations.
+ * vchOtherDerivationParameters is provided for alternative algorithms
+ * which may require more parameters (such as scrypt).
+ *
+ * Wallet Private Keys are then encrypted using AES-256-CBC
+ * with the double-sha256 of the public key as the IV, and the
+ * master key's key as the encryption key (see keystore.[ch]).
+ */
+
+/** Master key for wallet encryption */
+class CMasterKey
+{
+public:
+    std::vector<unsigned char> vchCryptedKey;
+    std::vector<unsigned char> vchSalt;
+    //! 0 = EVP_sha512()
+    //! 1 = scrypt()
+    unsigned int nDerivationMethod;
+    unsigned int nDeriveIterations;
+    //! Use this for more parameters to key derivation,
+    //! such as the various parameters to scrypt
+    std::vector<unsigned char> vchOtherDerivationParameters;
+
+    SERIALIZE_METHODS(CMasterKey, obj)
+    {
+        READWRITE(obj.vchCryptedKey, obj.vchSalt, obj.nDerivationMethod, obj.nDeriveIterations, obj.vchOtherDerivationParameters);
+    }
+
+    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);
+    }
+};
+
+typedef std::vector<unsigned char, secure_allocator<unsigned char> > CKeyingMaterial;
+
+namespace wallet_crypto_tests
+{
+    class TestCrypter;
+}
+
+/** Encryption/decryption context with key information */
+class CCrypter
+{
+friend class wallet_crypto_tests::TestCrypter; // for test access to chKey/chIV
+private:
+    std::vector<unsigned char, secure_allocator<unsigned char>> vchKey;
+    std::vector<unsigned char, secure_allocator<unsigned char>> vchIV;
+    bool fKeySet;
+
+    int BytesToKeySHA512AES(const std::vector<unsigned char>& chSalt, const SecureString& strKeyData, int count, unsigned char *key,unsigned char *iv) const;
+
+public:
+    bool SetKeyFromPassphrase(const SecureString &strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod);
+    bool Encrypt(const CKeyingMaterial& vchPlaintext, std::vector<unsigned char> &vchCiphertext) const;
+    bool Decrypt(const std::vector<unsigned char>& vchCiphertext, CKeyingMaterial& vchPlaintext) const;
+    bool SetKey(const CKeyingMaterial& chNewKey, const std::vector<unsigned char>& chNewIV);
+
+    void CleanKey()
+    {
+        memory_cleanse(vchKey.data(), vchKey.size());
+        memory_cleanse(vchIV.data(), vchIV.size());
+        fKeySet = false;
+    }
+
+    CCrypter()
+    {
+        fKeySet = false;
+        vchKey.resize(WALLET_CRYPTO_KEY_SIZE);
+        vchIV.resize(WALLET_CRYPTO_IV_SIZE);
+    }
+
+    ~CCrypter()
+    {
+        CleanKey();
+    }
+};
+
+bool EncryptSecret(const CKeyingMaterial& vMasterKey, const CKeyingMaterial &vchPlaintext, const uint256& nIV, std::vector<unsigned char> &vchCiphertext);
+bool DecryptSecret(const CKeyingMaterial& vMasterKey, const std::vector<unsigned char>& vchCiphertext, const uint256& nIV, CKeyingMaterial& vchPlaintext);
+bool DecryptKey(const CKeyingMaterial& vMasterKey, const std::vector<unsigned char>& vchCryptedSecret, const CPubKey& vchPubKey, CKey& key);
+
+#endif // DIGIBYTE_WALLET_CRYPTER_H