// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
-#include <openssl/aes.h>
#include <openssl/evp.h>
-//#include <openssl/crypto.h> // for OPENSSL_cleanse()
-#include <vector>
-#include <string>
-#ifdef WIN32
-#include <windows.h>
-#endif
#include "crypter.h"
-#include "scrypt.h"
-bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const std::vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod)
+using namespace std;
+
+//
+//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 = vector<unsigned char>(0);
+}
+
+//
+//CCrypter
+//
+
+bool CCrypter::SetKeyFromPassphrase(const SecureString& strKeyData, const vector<unsigned char>& chSalt, const unsigned int nRounds, const unsigned int nDerivationMethod)
{
if (nRounds < 1 || chSalt.size() != WALLET_CRYPTO_SALT_SIZE)
return false;
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 (nDerivationMethod == 1)
- {
- // Passphrase conversion
- uint256 scryptHash = scrypt_salted_multiround_hash((const void*)strKeyData.c_str(), strKeyData.size(), &chSalt[0], 8, nRounds);
-
- i = EVP_BytesToKey(EVP_aes_256_cbc(), EVP_sha512(), &chSalt[0],
- (unsigned char *)&scryptHash, sizeof scryptHash, nRounds, chKey, chIV);
- OPENSSL_cleanse(&scryptHash, sizeof scryptHash);
- }
-
-
if (i != (int)WALLET_CRYPTO_KEY_SIZE)
{
OPENSSL_cleanse(&chKey, sizeof chKey);
return true;
}
-bool CCrypter::SetKey(const CKeyingMaterial& chNewKey, const std::vector<unsigned char>& chNewIV)
+bool CCrypter::SetKey(const CKeyingMaterial& chNewKey, const vector<unsigned char>& chNewIV)
{
if (chNewKey.size() != WALLET_CRYPTO_KEY_SIZE || chNewIV.size() != WALLET_CRYPTO_KEY_SIZE)
return false;
return true;
}
-bool CCrypter::Encrypt(const CKeyingMaterial& vchPlaintext, std::vector<unsigned char> &vchCiphertext)
+bool CCrypter::Encrypt(const CKeyingMaterial& vchPlaintext, vector<unsigned char> &vchCiphertext)
{
if (!fKeySet)
return false;
+ const int AES_BLOCK_SIZE = 16; // taken from <openssl/aes.h>
+
// max ciphertext len for a n bytes of plaintext is
// n + AES_BLOCK_SIZE - 1 bytes
int nLen = vchPlaintext.size();
int nCLen = nLen + AES_BLOCK_SIZE, nFLen = 0;
- vchCiphertext = std::vector<unsigned char> (nCLen);
+ vchCiphertext = vector<unsigned char> (nCLen);
EVP_CIPHER_CTX ctx;
bool fOk = true;
EVP_CIPHER_CTX_init(&ctx);
- if (fOk) fOk = EVP_EncryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, chKey, chIV);
- if (fOk) fOk = EVP_EncryptUpdate(&ctx, &vchCiphertext[0], &nCLen, &vchPlaintext[0], nLen);
- if (fOk) fOk = EVP_EncryptFinal_ex(&ctx, (&vchCiphertext[0])+nCLen, &nFLen);
+ if (fOk) fOk = EVP_EncryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, chKey, chIV) != 0;
+ if (fOk) fOk = EVP_EncryptUpdate(&ctx, &vchCiphertext[0], &nCLen, &vchPlaintext[0], nLen) != 0;
+ if (fOk) fOk = EVP_EncryptFinal_ex(&ctx, (&vchCiphertext[0]) + nCLen, &nFLen) != 0;
EVP_CIPHER_CTX_cleanup(&ctx);
if (!fOk) return false;
return true;
}
-bool CCrypter::Decrypt(const std::vector<unsigned char>& vchCiphertext, CKeyingMaterial& vchPlaintext)
+bool CCrypter::Decrypt(const vector<unsigned char>& vchCiphertext, CKeyingMaterial& vchPlaintext)
{
if (!fKeySet)
return false;
bool fOk = true;
EVP_CIPHER_CTX_init(&ctx);
- if (fOk) fOk = EVP_DecryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, chKey, chIV);
- if (fOk) fOk = EVP_DecryptUpdate(&ctx, &vchPlaintext[0], &nPLen, &vchCiphertext[0], nLen);
- if (fOk) fOk = EVP_DecryptFinal_ex(&ctx, (&vchPlaintext[0])+nPLen, &nFLen);
+ if (fOk) fOk = EVP_DecryptInit_ex(&ctx, EVP_aes_256_cbc(), NULL, chKey, chIV) != 0;
+ if (fOk) fOk = EVP_DecryptUpdate(&ctx, &vchPlaintext[0], &nPLen, &vchCiphertext[0], nLen) != 0;
+ if (fOk) fOk = EVP_DecryptFinal_ex(&ctx, (&vchPlaintext[0]) + nPLen, &nFLen) != 0;
EVP_CIPHER_CTX_cleanup(&ctx);
if (!fOk) return false;
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)
+bool EncryptSecret(CKeyingMaterial& vMasterKey, const CSecret &vchPlaintext, const uint256& nIV, vector<unsigned char> &vchCiphertext)
{
CCrypter cKeyCrypter;
- std::vector<unsigned char> chIV(WALLET_CRYPTO_KEY_SIZE);
+ vector<unsigned char> chIV(WALLET_CRYPTO_KEY_SIZE);
memcpy(&chIV[0], &nIV, WALLET_CRYPTO_KEY_SIZE);
if(!cKeyCrypter.SetKey(vMasterKey, chIV))
return false;
return cKeyCrypter.Encrypt((CKeyingMaterial)vchPlaintext, vchCiphertext);
}
-bool DecryptSecret(const CKeyingMaterial& vMasterKey, const std::vector<unsigned char>& vchCiphertext, const uint256& nIV, CSecret& vchPlaintext)
+bool DecryptSecret(const CKeyingMaterial& vMasterKey, const vector<unsigned char>& vchCiphertext, const uint256& nIV, CSecret& vchPlaintext)
{
CCrypter cKeyCrypter;
- std::vector<unsigned char> chIV(WALLET_CRYPTO_KEY_SIZE);
+ vector<unsigned char> chIV(WALLET_CRYPTO_KEY_SIZE);
memcpy(&chIV[0], &nIV, WALLET_CRYPTO_KEY_SIZE);
if(!cKeyCrypter.SetKey(vMasterKey, chIV))
return false;