lbrycrd/src/crypter.cpp
Cory Fields 1630219d90 openssl: abstract out OPENSSL_cleanse
This makes it easier for us to replace it if desired, since it's now only in
one spot. Also, it avoids the openssl include from allocators.h, which
essentially forced openssl to be included from every compilation unit.
2015-02-15 11:34:02 -05:00

292 lines
8.5 KiB
C++

// Copyright (c) 2009-2013 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include "crypter.h"
#include "script/script.h"
#include "script/standard.h"
#include "util.h"
#include <string>
#include <vector>
#include <boost/foreach.hpp>
#include <openssl/aes.h>
#include <openssl/evp.h>
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)
return false;
int i = 0;
if (nDerivationMethod == 0)
i = EVP_BytesToKey(EVP_aes_256_cbc(), EVP_sha512(), &chSalt[0],
(unsigned char *)&strKeyData[0], strKeyData.size(), nRounds, chKey, chIV);
if (i != (int)WALLET_CRYPTO_KEY_SIZE)
{
memory_cleanse(chKey, sizeof(chKey));
memory_cleanse(chIV, sizeof(chIV));
return false;
}
fKeySet = true;
return true;
}
bool CCrypter::SetKey(const CKeyingMaterial& chNewKey, const std::vector<unsigned char>& chNewIV)
{
if (chNewKey.size() != WALLET_CRYPTO_KEY_SIZE || chNewIV.size() != WALLET_CRYPTO_KEY_SIZE)
return false;
memcpy(&chKey[0], &chNewKey[0], sizeof chKey);
memcpy(&chIV[0], &chNewIV[0], sizeof chIV);
fKeySet = true;
return true;
}
bool CCrypter::Encrypt(const CKeyingMaterial& vchPlaintext, std::vector<unsigned char> &vchCiphertext)
{
if (!fKeySet)
return false;
// 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);
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) != 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;
vchCiphertext.resize(nCLen + nFLen);
return true;
}
bool CCrypter::Decrypt(const std::vector<unsigned char>& vchCiphertext, CKeyingMaterial& vchPlaintext)
{
if (!fKeySet)
return false;
// plaintext will always be equal to or lesser than length of ciphertext
int nLen = vchCiphertext.size();
int nPLen = nLen, nFLen = 0;
vchPlaintext = CKeyingMaterial(nPLen);
EVP_CIPHER_CTX ctx;
bool fOk = true;
EVP_CIPHER_CTX_init(&ctx);
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;
vchPlaintext.resize(nPLen + nFLen);
return true;
}
static bool EncryptSecret(const CKeyingMaterial& vMasterKey, const CKeyingMaterial &vchPlaintext, const uint256& nIV, std::vector<unsigned char> &vchCiphertext)
{
CCrypter cKeyCrypter;
std::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(*((const CKeyingMaterial*)&vchPlaintext), vchCiphertext);
}
static bool DecryptSecret(const CKeyingMaterial& vMasterKey, const std::vector<unsigned char>& vchCiphertext, const uint256& nIV, CKeyingMaterial& vchPlaintext)
{
CCrypter cKeyCrypter;
std::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.Decrypt(vchCiphertext, *((CKeyingMaterial*)&vchPlaintext));
}
static bool DecryptKey(const CKeyingMaterial& vMasterKey, const std::vector<unsigned char>& vchCryptedSecret, const CPubKey& vchPubKey, CKey& key)
{
CKeyingMaterial vchSecret;
if(!DecryptSecret(vMasterKey, vchCryptedSecret, vchPubKey.GetHash(), vchSecret))
return false;
if (vchSecret.size() != 32)
return false;
key.Set(vchSecret.begin(), vchSecret.end(), vchPubKey.IsCompressed());
return key.VerifyPubKey(vchPubKey);
}
bool CCryptoKeyStore::SetCrypted()
{
LOCK(cs_KeyStore);
if (fUseCrypto)
return true;
if (!mapKeys.empty())
return false;
fUseCrypto = true;
return true;
}
bool CCryptoKeyStore::Lock()
{
if (!SetCrypted())
return false;
{
LOCK(cs_KeyStore);
vMasterKey.clear();
}
NotifyStatusChanged(this);
return true;
}
bool CCryptoKeyStore::Unlock(const CKeyingMaterial& vMasterKeyIn)
{
{
LOCK(cs_KeyStore);
if (!SetCrypted())
return false;
bool keyPass = false;
bool keyFail = false;
CryptedKeyMap::const_iterator mi = mapCryptedKeys.begin();
for (; mi != mapCryptedKeys.end(); ++mi)
{
const CPubKey &vchPubKey = (*mi).second.first;
const std::vector<unsigned char> &vchCryptedSecret = (*mi).second.second;
CKey key;
if (!DecryptKey(vMasterKeyIn, vchCryptedSecret, vchPubKey, key))
{
keyFail = true;
break;
}
keyPass = true;
if (fDecryptionThoroughlyChecked)
break;
}
if (keyPass && keyFail)
{
LogPrintf("The wallet is probably corrupted: Some keys decrypt but not all.");
assert(false);
}
if (keyFail || !keyPass)
return false;
vMasterKey = vMasterKeyIn;
fDecryptionThoroughlyChecked = true;
}
NotifyStatusChanged(this);
return true;
}
bool CCryptoKeyStore::AddKeyPubKey(const CKey& key, const CPubKey &pubkey)
{
{
LOCK(cs_KeyStore);
if (!IsCrypted())
return CBasicKeyStore::AddKeyPubKey(key, pubkey);
if (IsLocked())
return false;
std::vector<unsigned char> vchCryptedSecret;
CKeyingMaterial vchSecret(key.begin(), key.end());
if (!EncryptSecret(vMasterKey, vchSecret, pubkey.GetHash(), vchCryptedSecret))
return false;
if (!AddCryptedKey(pubkey, vchCryptedSecret))
return false;
}
return true;
}
bool CCryptoKeyStore::AddCryptedKey(const CPubKey &vchPubKey, const std::vector<unsigned char> &vchCryptedSecret)
{
{
LOCK(cs_KeyStore);
if (!SetCrypted())
return false;
mapCryptedKeys[vchPubKey.GetID()] = make_pair(vchPubKey, vchCryptedSecret);
}
return true;
}
bool CCryptoKeyStore::GetKey(const CKeyID &address, CKey& keyOut) const
{
{
LOCK(cs_KeyStore);
if (!IsCrypted())
return CBasicKeyStore::GetKey(address, keyOut);
CryptedKeyMap::const_iterator mi = mapCryptedKeys.find(address);
if (mi != mapCryptedKeys.end())
{
const CPubKey &vchPubKey = (*mi).second.first;
const std::vector<unsigned char> &vchCryptedSecret = (*mi).second.second;
return DecryptKey(vMasterKey, vchCryptedSecret, vchPubKey, keyOut);
}
}
return false;
}
bool CCryptoKeyStore::GetPubKey(const CKeyID &address, CPubKey& vchPubKeyOut) const
{
{
LOCK(cs_KeyStore);
if (!IsCrypted())
return CKeyStore::GetPubKey(address, vchPubKeyOut);
CryptedKeyMap::const_iterator mi = mapCryptedKeys.find(address);
if (mi != mapCryptedKeys.end())
{
vchPubKeyOut = (*mi).second.first;
return true;
}
}
return false;
}
bool CCryptoKeyStore::EncryptKeys(CKeyingMaterial& vMasterKeyIn)
{
{
LOCK(cs_KeyStore);
if (!mapCryptedKeys.empty() || IsCrypted())
return false;
fUseCrypto = true;
BOOST_FOREACH(KeyMap::value_type& mKey, mapKeys)
{
const CKey &key = mKey.second;
CPubKey vchPubKey = key.GetPubKey();
CKeyingMaterial vchSecret(key.begin(), key.end());
std::vector<unsigned char> vchCryptedSecret;
if (!EncryptSecret(vMasterKeyIn, vchSecret, vchPubKey.GetHash(), vchCryptedSecret))
return false;
if (!AddCryptedKey(vchPubKey, vchCryptedSecret))
return false;
}
mapKeys.clear();
}
return true;
}