twister-core/src/wallet.cpp

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2012 The Bitcoin developers
// Distributed under the MIT/X11 software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.

#include "wallet.h"
#include "walletdb.h"
#include "crypter.h"
#include "ui_interface.h"
#include "base58.h"
#include <boost/algorithm/string/replace.hpp>

using namespace std;


//////////////////////////////////////////////////////////////////////////////
//
// mapWallet
//

struct CompareValueOnly
{
    bool operator()(const pair<int64, pair<const CWalletTx*, unsigned int> >& t1,
                    const pair<int64, pair<const CWalletTx*, unsigned int> >& t2) const
    {
        return t1.first < t2.first;
    }
};

CPubKey CWallet::GenerateNewKey(std::string username)
{
    bool fCompressed = CanSupportFeature(FEATURE_COMPRPUBKEY); // default to compressed public keys if we want 0.6.0 wallets

    RandAddSeedPerfmon();
    CKey secret;
    secret.MakeNewKey(fCompressed);

    // Compressed public keys were introduced in version 0.6.0
    if (fCompressed)
        SetMinVersion(FEATURE_COMPRPUBKEY);

    CPubKey pubkey = secret.GetPubKey();

    // Create new metadata
    int64 nCreationTime = GetTime();
    mapKeyMetadata[pubkey.GetID()] = CKeyMetadata(nCreationTime, username);
    if (!nTimeFirstKey || nCreationTime < nTimeFirstKey)
        nTimeFirstKey = nCreationTime;

    if (!AddKeyPubKey(secret, pubkey))
        throw std::runtime_error("CWallet::GenerateNewKey() : AddKey failed");
    return pubkey;
}

bool CWallet::AddKeyPubKey(const CKey& secret, const CPubKey &pubkey)
{
    if (!CCryptoKeyStore::AddKeyPubKey(secret, pubkey))
        return false;
    if (!fFileBacked)
        return true;
    if (!IsCrypted()) {
        return CWalletDB(strWalletFile).WriteKey(pubkey,
                                                 secret.GetPrivKey(),
                                                 mapKeyMetadata[pubkey.GetID()]);
    }
    return true;
}

bool CWallet::AddCryptedKey(const CPubKey &vchPubKey,
                            const vector<unsigned char> &vchCryptedSecret)
{
    if (!CCryptoKeyStore::AddCryptedKey(vchPubKey, vchCryptedSecret))
        return false;
    if (!fFileBacked)
        return true;
    {
        LOCK(cs_wallet);
        if (pwalletdbEncryption)
            return pwalletdbEncryption->WriteCryptedKey(vchPubKey,
                                                        vchCryptedSecret,
                                                        mapKeyMetadata[vchPubKey.GetID()]);
        else
            return CWalletDB(strWalletFile).WriteCryptedKey(vchPubKey,
                                                            vchCryptedSecret,
                                                            mapKeyMetadata[vchPubKey.GetID()]);
    }
    return false;
}

bool CWallet::LoadKeyMetadata(const CPubKey &pubkey, const CKeyMetadata &meta)
{
    if (meta.nCreateTime && (!nTimeFirstKey || meta.nCreateTime < nTimeFirstKey))
        nTimeFirstKey = meta.nCreateTime;

    mapKeyMetadata[pubkey.GetID()] = meta;
    return true;
}

bool CWallet::GetKeyIdFromUsername(std::string username, CKeyID &keyid)
{
  for (std::map<CKeyID, CKeyMetadata>::const_iterator it = mapKeyMetadata.begin(); it != mapKeyMetadata.end(); it++) {
    if (it->second.username == username) {
        keyid = it->first;
        return true;
    }
  }
  return false;
}

bool CWallet::LoadCryptedKey(const CPubKey &vchPubKey, const std::vector<unsigned char> &vchCryptedSecret)
{
    return CCryptoKeyStore::AddCryptedKey(vchPubKey, vchCryptedSecret);
}

bool CWallet::Unlock(const SecureString& strWalletPassphrase)
{
    CCrypter crypter;
    CKeyingMaterial vMasterKey;

    {
        LOCK(cs_wallet);
        BOOST_FOREACH(const MasterKeyMap::value_type& pMasterKey, mapMasterKeys)
        {
            if(!crypter.SetKeyFromPassphrase(strWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod))
                return false;
            if (!crypter.Decrypt(pMasterKey.second.vchCryptedKey, vMasterKey))
                continue; // try another master key
            if (CCryptoKeyStore::Unlock(vMasterKey))
                return true;
        }
    }
    return false;
}

bool CWallet::ChangeWalletPassphrase(const SecureString& strOldWalletPassphrase, const SecureString& strNewWalletPassphrase)
{
    bool fWasLocked = IsLocked();

    {
        LOCK(cs_wallet);
        Lock();

        CCrypter crypter;
        CKeyingMaterial vMasterKey;
        BOOST_FOREACH(MasterKeyMap::value_type& pMasterKey, mapMasterKeys)
        {
            if(!crypter.SetKeyFromPassphrase(strOldWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod))
                return false;
            if (!crypter.Decrypt(pMasterKey.second.vchCryptedKey, vMasterKey))
                return false;
            if (CCryptoKeyStore::Unlock(vMasterKey))
            {
                int64 nStartTime = GetTimeMillis();
                crypter.SetKeyFromPassphrase(strNewWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod);
                pMasterKey.second.nDeriveIterations = pMasterKey.second.nDeriveIterations * (100 / ((double)(GetTimeMillis() - nStartTime)));

                nStartTime = GetTimeMillis();
                crypter.SetKeyFromPassphrase(strNewWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod);
                pMasterKey.second.nDeriveIterations = (pMasterKey.second.nDeriveIterations + pMasterKey.second.nDeriveIterations * 100 / ((double)(GetTimeMillis() - nStartTime))) / 2;

                if (pMasterKey.second.nDeriveIterations < 25000)
                    pMasterKey.second.nDeriveIterations = 25000;

                printf("Wallet passphrase changed to an nDeriveIterations of %i\n", pMasterKey.second.nDeriveIterations);

                if (!crypter.SetKeyFromPassphrase(strNewWalletPassphrase, pMasterKey.second.vchSalt, pMasterKey.second.nDeriveIterations, pMasterKey.second.nDerivationMethod))
                    return false;
                if (!crypter.Encrypt(vMasterKey, pMasterKey.second.vchCryptedKey))
                    return false;
                CWalletDB(strWalletFile).WriteMasterKey(pMasterKey.first, pMasterKey.second);
                if (fWasLocked)
                    Lock();
                return true;
            }
        }
    }

    return false;
}

void CWallet::SetBestChain(const CBlockLocator& loc)
{
    CWalletDB walletdb(strWalletFile);
    walletdb.WriteBestBlock(loc);
}

// This class implements an addrIncoming entry that causes pre-0.4
// clients to crash on startup if reading a private-key-encrypted wallet.
class CCorruptAddress
{
public:
    IMPLEMENT_SERIALIZE
    (
        if (nType & SER_DISK)
            READWRITE(nVersion);
    )
};

bool CWallet::SetMinVersion(enum WalletFeature nVersion, CWalletDB* pwalletdbIn, bool fExplicit)
{
    if (nWalletVersion >= nVersion)
        return true;

    // when doing an explicit upgrade, if we pass the max version permitted, upgrade all the way
    if (fExplicit && nVersion > nWalletMaxVersion)
            nVersion = FEATURE_LATEST;

    nWalletVersion = nVersion;

    if (nVersion > nWalletMaxVersion)
        nWalletMaxVersion = nVersion;

    if (fFileBacked)
    {
        CWalletDB* pwalletdb = pwalletdbIn ? pwalletdbIn : new CWalletDB(strWalletFile);
        if (nWalletVersion >= 40000)
        {
            // Versions prior to 0.4.0 did not support the "minversion" record.
            // Use a CCorruptAddress to make them crash instead.
            CCorruptAddress corruptAddress;
            pwalletdb->WriteSetting("addrIncoming", corruptAddress);
        }
        if (nWalletVersion > 40000)
            pwalletdb->WriteMinVersion(nWalletVersion);
        if (!pwalletdbIn)
            delete pwalletdb;
    }

    return true;
}

bool CWallet::SetMaxVersion(int nVersion)
{
    // cannot downgrade below current version
    if (nWalletVersion > nVersion)
        return false;

    nWalletMaxVersion = nVersion;

    return true;
}

bool CWallet::EncryptWallet(const SecureString& strWalletPassphrase)
{
    if (IsCrypted())
        return false;

    CKeyingMaterial vMasterKey;
    RandAddSeedPerfmon();

    vMasterKey.resize(WALLET_CRYPTO_KEY_SIZE);
    RAND_bytes(&vMasterKey[0], WALLET_CRYPTO_KEY_SIZE);

    CMasterKey kMasterKey;

    RandAddSeedPerfmon();
    kMasterKey.vchSalt.resize(WALLET_CRYPTO_SALT_SIZE);
    RAND_bytes(&kMasterKey.vchSalt[0], WALLET_CRYPTO_SALT_SIZE);

    CCrypter crypter;
    int64 nStartTime = GetTimeMillis();
    crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt, 25000, kMasterKey.nDerivationMethod);
    kMasterKey.nDeriveIterations = 2500000 / ((double)(GetTimeMillis() - nStartTime));

    nStartTime = GetTimeMillis();
    crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt, kMasterKey.nDeriveIterations, kMasterKey.nDerivationMethod);
    kMasterKey.nDeriveIterations = (kMasterKey.nDeriveIterations + kMasterKey.nDeriveIterations * 100 / ((double)(GetTimeMillis() - nStartTime))) / 2;

    if (kMasterKey.nDeriveIterations < 25000)
        kMasterKey.nDeriveIterations = 25000;

    printf("Encrypting Wallet with an nDeriveIterations of %i\n", kMasterKey.nDeriveIterations);

    if (!crypter.SetKeyFromPassphrase(strWalletPassphrase, kMasterKey.vchSalt, kMasterKey.nDeriveIterations, kMasterKey.nDerivationMethod))
        return false;
    if (!crypter.Encrypt(vMasterKey, kMasterKey.vchCryptedKey))
        return false;

    {
        LOCK(cs_wallet);
        mapMasterKeys[++nMasterKeyMaxID] = kMasterKey;
        if (fFileBacked)
        {
            pwalletdbEncryption = new CWalletDB(strWalletFile);
            if (!pwalletdbEncryption->TxnBegin())
                return false;
            pwalletdbEncryption->WriteMasterKey(nMasterKeyMaxID, kMasterKey);
        }

        if (!EncryptKeys(vMasterKey))
        {
            if (fFileBacked)
                pwalletdbEncryption->TxnAbort();
            exit(1); //We now probably have half of our keys encrypted in memory, and half not...die and let the user reload their unencrypted wallet.
        }

        // Encryption was introduced in version 0.4.0
        SetMinVersion(FEATURE_WALLETCRYPT, pwalletdbEncryption, true);

        if (fFileBacked)
        {
            if (!pwalletdbEncryption->TxnCommit())
                exit(1); //We now have keys encrypted in memory, but no on disk...die to avoid confusion and let the user reload their unencrypted wallet.

            delete pwalletdbEncryption;
            pwalletdbEncryption = NULL;
        }

        Lock();
        Unlock(strWalletPassphrase);
        Lock();

        // Need to completely rewrite the wallet file; if we don't, bdb might keep
        // bits of the unencrypted private key in slack space in the database file.
        CDB::Rewrite(strWalletFile);

    }
    NotifyStatusChanged(this);

    return true;
}

int64 CWallet::IncOrderPosNext(CWalletDB *pwalletdb)
{
    int64 nRet = nOrderPosNext++;
    if (pwalletdb) {
        pwalletdb->WriteOrderPosNext(nOrderPosNext);
    } else {
        CWalletDB(strWalletFile).WriteOrderPosNext(nOrderPosNext);
    }
    return nRet;
}

void CWallet::MarkDirty()
{
    {
        LOCK(cs_wallet);
        /*
        BOOST_FOREACH(PAIRTYPE(const uint256, CWalletTx)& item, mapWallet)
            item.second.MarkDirty();
        */
    }
}

bool CWallet::AddToWallet(const CWalletTx& wtxIn)
{
    uint256 hash = wtxIn.GetHash();
    {
        LOCK(cs_wallet);
        // Inserts only if not already there, returns tx inserted or tx found
        pair<map<uint256, CWalletTx>::iterator, bool> ret = mapWallet.insert(make_pair(hash, wtxIn));
        CWalletTx& wtx = (*ret.first).second;
        wtx.BindWallet(this);
        bool fInsertedNew = ret.second;
        if (fInsertedNew)
        {
            wtx.nTimeReceived = GetAdjustedTime();
            wtx.nOrderPos = IncOrderPosNext();

            wtx.nTimeSmart = wtx.nTimeReceived;
            if (wtxIn.hashBlock != 0)
            {
                if (mapBlockIndex.count(wtxIn.hashBlock))
                {
                    unsigned int& blocktime = mapBlockIndex[wtxIn.hashBlock]->nTime;
                    wtx.nTimeSmart = blocktime;
                }
                else
                    printf("AddToWallet() : found %s in block %s not in index\n",
                           wtxIn.GetHash().ToString().c_str(),
                           wtxIn.hashBlock.ToString().c_str());
            }
        }

        bool fUpdated = false;
        if (!fInsertedNew)
        {
            // Merge
            if (wtxIn.hashBlock != 0 && wtxIn.hashBlock != wtx.hashBlock)
            {
                wtx.hashBlock = wtxIn.hashBlock;
                fUpdated = true;
            }
            if (wtxIn.nIndex != -1 && (wtxIn.vMerkleBranch != wtx.vMerkleBranch || wtxIn.nIndex != wtx.nIndex))
            {
                wtx.vMerkleBranch = wtxIn.vMerkleBranch;
                wtx.nIndex = wtxIn.nIndex;
                fUpdated = true;
            }
            if (wtxIn.fFromMe && wtxIn.fFromMe != wtx.fFromMe)
            {
                wtx.fFromMe = wtxIn.fFromMe;
                fUpdated = true;
            }
        }

        //// debug print
        printf("AddToWallet %s  %s%s\n", wtxIn.GetHash().ToString().c_str(), (fInsertedNew ? "new" : ""), (fUpdated ? "update" : ""));

        // Write to disk
        if (fInsertedNew || fUpdated)
            if (!wtx.WriteToDisk())
                return false;

        if (!fHaveGUI) {
            // If default receiving address gets used, replace it with a new one
            if (vchDefaultKey.IsValid()) {
                CScript scriptDefaultKey;
                scriptDefaultKey.SetDestination(vchDefaultKey.GetID());
                /*
                BOOST_FOREACH(const CTxOut& txout, wtx.vout)
                {
                    if (txout.scriptPubKey == scriptDefaultKey)
                    {
                        CPubKey newDefaultKey;
                        if (GetKeyFromPool(newDefaultKey, false))
                        {
                            SetDefaultKey(newDefaultKey);
                            SetAddressBookName(vchDefaultKey.GetID(), "");
                        }
                    }
                }
                */
            }
        }

        // Notify UI of new or updated transaction
        NotifyTransactionChanged(this, hash, fInsertedNew ? CT_NEW : CT_UPDATED);

        // notify an external script when a wallet transaction comes in or is updated
        std::string strCmd = GetArg("-walletnotify", "");

        if ( !strCmd.empty())
        {
            boost::replace_all(strCmd, "%s", wtxIn.GetHash().GetHex());
            boost::thread t(runCommand, strCmd); // thread runs free
        }

    }
    return true;
}

// Add a transaction to the wallet, or update it.
// pblock is optional, but should be provided if the transaction is known to be in a block.
// If fUpdate is true, existing transactions will be updated.
bool CWallet::AddToWalletIfInvolvingMe(const uint256 &hash, const CTransaction& tx, const CBlock* pblock, bool fUpdate, bool fFindBlock)
{
    {
        LOCK(cs_wallet);
        bool fExisted = mapWallet.count(hash);
        if (fExisted && !fUpdate) return false;
        if (fExisted || IsMine(tx) || IsFromMe(tx))
        {
            CWalletTx wtx(this,tx);
            // Get merkle branch if transaction was found in a block
            if (pblock)
                wtx.SetMerkleBranch(pblock);
            return AddToWallet(wtx);
        }
    }
    return false;
}

bool CWallet::EraseFromWallet(uint256 hash)
{
    if (!fFileBacked)
        return false;
    {
        LOCK(cs_wallet);
        if (mapWallet.erase(hash))
            CWalletDB(strWalletFile).EraseTx(hash);
    }
    return true;
}


int64 CWalletTx::GetTxTime() const
{
    int64 n = nTimeSmart;
    return n ? n : nTimeReceived;
}

int CWalletTx::GetRequestCount() const
{
    // Returns -1 if it wasn't being tracked
    int nRequests = -1;
    {
        LOCK(pwallet->cs_wallet);
        if (IsSpamMessage())
        {
            // Generated block
            if (hashBlock != 0)
            {
                map<uint256, int>::const_iterator mi = pwallet->mapRequestCount.find(hashBlock);
                if (mi != pwallet->mapRequestCount.end())
                    nRequests = (*mi).second;
            }
        }
        else
        {
            // Did anyone request this transaction?
            map<uint256, int>::const_iterator mi = pwallet->mapRequestCount.find(GetHash());
            if (mi != pwallet->mapRequestCount.end())
            {
                nRequests = (*mi).second;

                // How about the block it's in?
                if (nRequests == 0 && hashBlock != 0)
                {
                    map<uint256, int>::const_iterator mi = pwallet->mapRequestCount.find(hashBlock);
                    if (mi != pwallet->mapRequestCount.end())
                        nRequests = (*mi).second;
                    else
                        nRequests = 1; // If it's in someone else's block it must have got out
                }
            }
        }
    }
    return nRequests;
}


void CWalletTx::AddSupportingTransactions()
{
// [MF] remove me
}

bool CWalletTx::WriteToDisk()
{
    return CWalletDB(pwallet->strWalletFile).WriteTx(GetHash(), *this);
}

// Scan the block chain (starting in pindexStart) for transactions
// from or to us. If fUpdate is true, found transactions that already
// exist in the wallet will be updated.
int CWallet::ScanForWalletTransactions(CBlockIndex* pindexStart, bool fUpdate)
{
    int ret = 0;

    CBlockIndex* pindex = pindexStart;
    {
        LOCK(cs_wallet);
        while (pindex)
        {
            // no need to read and scan block, if block was created before
            // our wallet birthday (as adjusted for block time variability)
            if (nTimeFirstKey && (pindex->nTime < (nTimeFirstKey - 7200))) {
                pindex = pindex->GetNextInMainChain();
                continue;
            }

            CBlock block;
            ReadBlockFromDisk(block, pindex);
            BOOST_FOREACH(CTransaction& tx, block.vtx)
            {
                if (AddToWalletIfInvolvingMe(tx.GetHash(), tx, &block, fUpdate))
                    ret++;
            }
            pindex = pindex->GetNextInMainChain();
        }
    }
    return ret;
}

void CWallet::ReacceptWalletTransactions()
{
    bool fRepeat = true;
    while (fRepeat)
    {
        LOCK(cs_wallet);
        fRepeat = false;
        bool fMissing = false;
        BOOST_FOREACH(PAIRTYPE(const uint256, CWalletTx)& item, mapWallet)
        {
            CWalletTx& wtx = item.second;
            if (wtx.IsSpamMessage() )
                continue;

            CTransaction tx;
            uint256 hashBlock;
            bool fUpdated = false;
            bool fFound = false;
            // [MF] can't use GetTransaction from main.cpp here. so?
            // GetTransaction(wtx.GetUsernameHash(), tx, hashBlock);
            if (fFound || wtx.GetDepthInMainChain() > 0)
            {
              /*
                // Update fSpent if a tx got spent somewhere else by a copy of wallet.dat
                for (unsigned int i = 0; i < wtx.vout.size(); i++)
                {
                    if (wtx.IsSpent(i))
                        continue;
                    if ((i >= coins.vout.size() || coins.vout[i].IsNull()) && IsMine(wtx.vout[i]))
                    {
                        wtx.MarkSpent(i);
                        fUpdated = true;
                        fMissing = true;
                    }
                }
                if (fUpdated)
                {
                    printf("ReacceptWalletTransactions found spent coin %sbc %s\n", FormatMoney(wtx.GetCredit()).c_str(), wtx.GetHash().ToString().c_str());
                    wtx.MarkDirty();
                    wtx.WriteToDisk();
                }
                */
            }
            else
            {
                // Re-accept any txes of ours that aren't already in a block
                if (!wtx.IsSpamMessage())
                    wtx.AcceptWalletTransaction();
            }
        }
        if (fMissing)
        {
            // TODO: optimize this to scan just part of the block chain?
            if (ScanForWalletTransactions(pindexGenesisBlock))
                fRepeat = true;  // Found missing transactions: re-do re-accept.
        }
    }
}

void CWalletTx::RelayWalletTransaction()
{
    if (!IsSpamMessage())
    {
        if (GetDepthInMainChain() == 0) {
            uint256 hash = GetUsernameHash();
            printf("Relaying wtx %s\n", hash.ToString().c_str());
            RelayTransaction((CTransaction)*this, hash);
        }
    }
}

void CWallet::ResendWalletTransactions()
{
    // Do this infrequently and randomly to avoid giving away
    // that these are our transactions.
    static int64 nNextTime;
    if (GetTime() < nNextTime)
        return;
    bool fFirst = (nNextTime == 0);
    nNextTime = GetTime() + GetRand(30 * 60);
    if (fFirst)
        return;

    // Only do it if there's been a new block since last time
    static int64 nLastTime;
    if (nTimeBestReceived < nLastTime)
        return;
    nLastTime = GetTime();

    // Rebroadcast any of our txes that aren't in a block yet
    printf("ResendWalletTransactions()\n");
    {
        LOCK(cs_wallet);
        // Sort them in chronological order
        multimap<unsigned int, CWalletTx*> mapSorted;
        BOOST_FOREACH(PAIRTYPE(const uint256, CWalletTx)& item, mapWallet)
        {
            CWalletTx& wtx = item.second;
            // Don't rebroadcast until it's had plenty of time that
            // it should have gotten in already by now.
            if (nTimeBestReceived - (int64)wtx.nTimeReceived > 5 * 60)
                mapSorted.insert(make_pair(wtx.nTimeReceived, &wtx));
        }
        BOOST_FOREACH(PAIRTYPE(const unsigned int, CWalletTx*)& item, mapSorted)
        {
            CWalletTx& wtx = *item.second;
            wtx.RelayWalletTransaction();
        }
    }
}






//////////////////////////////////////////////////////////////////////////////
//
// Actions
//

bool CWallet::CreateTransaction(const vector<pair<CScript, int64> >& vecSend,
                                CWalletTx& wtxNew, CReserveKey& reservekey, int64& nFeeRet, std::string& strFailReason)
{
    int64 nValue = 0;
    BOOST_FOREACH (const PAIRTYPE(CScript, int64)& s, vecSend)
    {
        if (nValue < 0)
        {
            strFailReason = _("Transaction amounts must be positive");
            return false;
        }
        nValue += s.second;
    }
    if (vecSend.empty() || nValue < 0)
    {
        strFailReason = _("Transaction amounts must be positive");
        return false;
    }

    wtxNew.BindWallet(this);

    {
        LOCK2(cs_main, cs_wallet);
        {
            nFeeRet = nTransactionFee;
            /*
            loop
            {
                wtxNew.vin.clear();
                wtxNew.vout.clear();
                wtxNew.fFromMe = true;

                int64 nTotalValue = nValue + nFeeRet;
                double dPriority = 0;
                // vouts to the payees
                BOOST_FOREACH (const PAIRTYPE(CScript, int64)& s, vecSend)
                {
                    CTxOut txout(s.second, s.first);
                    if (txout.IsDust(CTransaction::nMinRelayTxFee))
                    {
                        strFailReason = _("Transaction amount too small");
                        return false;
                    }
                    wtxNew.vout.push_back(txout);
                }

                // Choose coins to use
                set<pair<const CWalletTx*,unsigned int> > setCoins;
                int64 nValueIn = 0;
                if (!SelectCoins(nTotalValue, setCoins, nValueIn))
                {
                    strFailReason = _("Insufficient funds");
                    return false;
                }
                BOOST_FOREACH(PAIRTYPE(const CWalletTx*, unsigned int) pcoin, setCoins)
                {
                    int64 nCredit = pcoin.first->vout[pcoin.second].nValue;
                    //The priority after the next block (depth+1) is used instead of the current,
                    //reflecting an assumption the user would accept a bit more delay for
                    //a chance at a free transaction.
                    dPriority += (double)nCredit * (pcoin.first->GetDepthInMainChain()+1);
                }

                int64 nChange = nValueIn - nValue - nFeeRet;
                // if sub-cent change is required, the fee must be raised to at least nMinTxFee
                // or until nChange becomes zero
                // NOTE: this depends on the exact behaviour of GetMinFee
                if (nFeeRet < CTransaction::nMinTxFee && nChange > 0 && nChange < CENT)
                {
                    int64 nMoveToFee = min(nChange, CTransaction::nMinTxFee - nFeeRet);
                    nChange -= nMoveToFee;
                    nFeeRet += nMoveToFee;
                }

                if (nChange > 0)
                {
                    // Note: We use a new key here to keep it from being obvious which side is the change.
                    //  The drawback is that by not reusing a previous key, the change may be lost if a
                    //  backup is restored, if the backup doesn't have the new private key for the change.
                    //  If we reused the old key, it would be possible to add code to look for and
                    //  rediscover unknown transactions that were written with keys of ours to recover
                    //  post-backup change.

                    // Reserve a new key pair from key pool
                    CPubKey vchPubKey;
                    assert(reservekey.GetReservedKey(vchPubKey)); // should never fail, as we just unlocked

                    // Fill a vout to ourself
                    // TODO: pass in scriptChange instead of reservekey so
                    // change transaction isn't always pay-to-bitcoin-address
                    CScript scriptChange;
                    scriptChange.SetDestination(vchPubKey.GetID());

                    CTxOut newTxOut(nChange, scriptChange);

                    // Never create dust outputs; if we would, just
                    // add the dust to the fee.
                    if (newTxOut.IsDust(CTransaction::nMinRelayTxFee))
                    {
                        nFeeRet += nChange;
                        reservekey.ReturnKey();
                    }
                    else
                    {
                        // Insert change txn at random position:
                        vector<CTxOut>::iterator position = wtxNew.vout.begin()+GetRandInt(wtxNew.vout.size()+1);
                        wtxNew.vout.insert(position, newTxOut);
                    }
                }
                else
                    reservekey.ReturnKey();

                // Fill vin
                BOOST_FOREACH(const PAIRTYPE(const CWalletTx*,unsigned int)& coin, setCoins)
                    wtxNew.vin.push_back(CTxIn(coin.first->GetHash(),coin.second));

                // Sign
                int nIn = 0;
                BOOST_FOREACH(const PAIRTYPE(const CWalletTx*,unsigned int)& coin, setCoins)
                    if (!SignSignature(*this, *coin.first, wtxNew, nIn++))
                    {
                        strFailReason = _("Signing transaction failed");
                        return false;
                    }

                // Limit size
                unsigned int nBytes = ::GetSerializeSize(*(CTransaction*)&wtxNew, SER_NETWORK, PROTOCOL_VERSION);
                if (nBytes >= MAX_STANDARD_TX_SIZE)
                {
                    strFailReason = _("Transaction too large");
                    return false;
                }
                dPriority /= nBytes;

                // Check that enough fee is included
                int64 nPayFee = nTransactionFee * (1 + (int64)nBytes / 1000);
                bool fAllowFree = AllowFree(dPriority);
                int64 nMinFee = GetMinFee(wtxNew, fAllowFree, GMF_SEND);
                if (nFeeRet < max(nPayFee, nMinFee))
                {
                    nFeeRet = max(nPayFee, nMinFee);
                    continue;
                }

                // Fill vtxPrev by copying from previous transactions vtxPrev
                wtxNew.AddSupportingTransactions();
                wtxNew.fTimeReceivedIsTxTime = true;

                break;
            }
            */
        }
    }
    return true;
}

bool CWallet::CreateTransaction(CScript scriptPubKey, int64 nValue,
                                CWalletTx& wtxNew, CReserveKey& reservekey, int64& nFeeRet, std::string& strFailReason)
{
    vector< pair<CScript, int64> > vecSend;
    vecSend.push_back(make_pair(scriptPubKey, nValue));
    return CreateTransaction(vecSend, wtxNew, reservekey, nFeeRet, strFailReason);
}

// Call after CreateTransaction unless you want to abort
bool CWallet::CommitTransaction(CWalletTx& wtxNew, CReserveKey& reservekey)
{
    {
        LOCK2(cs_main, cs_wallet);
        printf("CommitTransaction:\n%s", wtxNew.ToString().c_str());
        {
            // This is only to keep the database open to defeat the auto-flush for the
            // duration of this scope.  This is the only place where this optimization
            // maybe makes sense; please don't do it anywhere else.
            CWalletDB* pwalletdb = fFileBacked ? new CWalletDB(strWalletFile,"r") : NULL;

            // Take key pair from key pool so it won't be used again
            reservekey.KeepKey();

            // Add tx to wallet, because if it has change it's also ours,
            // otherwise just for transaction history.
            AddToWallet(wtxNew);

            // Mark old coins as spent
            set<CWalletTx*> setCoins;
            /*
            BOOST_FOREACH(const CTxIn& txin, wtxNew.vin)
            {
                CWalletTx &coin = mapWallet[txin.prevout.hash];
                coin.BindWallet(this);
                coin.MarkSpent(txin.prevout.n);
                coin.WriteToDisk();
                NotifyTransactionChanged(this, coin.GetHash(), CT_UPDATED);
            }
            */

            if (fFileBacked)
                delete pwalletdb;
        }

        // Track how many getdata requests our transaction gets
        mapRequestCount[wtxNew.GetHash()] = 0;

        // Broadcast
        if (!wtxNew.AcceptToMemoryPool(false))
        {
            // This must not fail. The transaction has already been signed and recorded.
            printf("CommitTransaction() : Error: Transaction not valid");
            return false;
        }
        wtxNew.RelayWalletTransaction();
    }
    return true;
}




string CWallet::SendMoney(CScript scriptPubKey, int64 nValue, CWalletTx& wtxNew, bool fAskFee)
{
    CReserveKey reservekey(this);
    int64 nFeeRequired;

    if (IsLocked())
    {
        string strError = _("Error: Wallet locked, unable to create transaction!");
        printf("SendMoney() : %s", strError.c_str());
        return strError;
    }
    string strError;
    if (!CreateTransaction(scriptPubKey, nValue, wtxNew, reservekey, nFeeRequired, strError))
    {
        printf("SendMoney() : %s\n", strError.c_str());
        return strError;
    }

    if (fAskFee && !uiInterface.ThreadSafeAskFee(nFeeRequired))
        return "ABORTED";

    if (!CommitTransaction(wtxNew, reservekey))
        return _("Error: The transaction was rejected! This might happen if some of the coins in your wallet were already spent, such as if you used a copy of wallet.dat and coins were spent in the copy but not marked as spent here.");

    return "";
}



DBErrors CWallet::LoadWallet(bool& fFirstRunRet)
{
    if (!fFileBacked)
        return DB_LOAD_OK;
    fFirstRunRet = false;
    DBErrors nLoadWalletRet = CWalletDB(strWalletFile,"cr+").LoadWallet(this);
    if (nLoadWalletRet == DB_NEED_REWRITE)
    {
        if (CDB::Rewrite(strWalletFile, "\x04pool"))
        {
            setKeyPool.clear();
            // Note: can't top-up keypool here, because wallet is locked.
            // User will be prompted to unlock wallet the next operation
            // the requires a new key.
        }
    }

    if (nLoadWalletRet != DB_LOAD_OK)
        return nLoadWalletRet;
    fFirstRunRet = !vchDefaultKey.IsValid();

    return DB_LOAD_OK;
}


bool CWallet::SetAddressBookName(const CTxDestination& address, const string& strName)
{
    std::map<CTxDestination, std::string>::iterator mi = mapAddressBook.find(address);
    mapAddressBook[address] = strName;
    NotifyAddressBookChanged(this, address, strName, ::IsMine(*this, address), (mi == mapAddressBook.end()) ? CT_NEW : CT_UPDATED);
    if (!fFileBacked)
        return false;
    return CWalletDB(strWalletFile).WriteName(CBitcoinAddress(address).ToString(), strName);
}

bool CWallet::DelAddressBookName(const CTxDestination& address)
{
    mapAddressBook.erase(address);
    NotifyAddressBookChanged(this, address, "", ::IsMine(*this, address), CT_DELETED);
    if (!fFileBacked)
        return false;
    return CWalletDB(strWalletFile).EraseName(CBitcoinAddress(address).ToString());
}


bool CWallet::SetDefaultKey(const CPubKey &vchPubKey)
{
    if (fFileBacked)
    {
        if (!CWalletDB(strWalletFile).WriteDefaultKey(vchPubKey))
            return false;
    }
    vchDefaultKey = vchPubKey;
    return true;
}

bool GetWalletFile(CWallet* pwallet, string &strWalletFileOut)
{
    if (!pwallet->fFileBacked)
        return false;
    strWalletFileOut = pwallet->strWalletFile;
    return true;
}


void CWallet::ReserveKeyFromKeyPool(int64& nIndex, CKeyPool& keypool)
{
    nIndex = -1;
    keypool.vchPubKey = CPubKey();
    {
        LOCK(cs_wallet);

        // Get the oldest key
        if(setKeyPool.empty())
            return;

        CWalletDB walletdb(strWalletFile);

        nIndex = *(setKeyPool.begin());
        setKeyPool.erase(setKeyPool.begin());
        if (!walletdb.ReadPool(nIndex, keypool))
            throw runtime_error("ReserveKeyFromKeyPool() : read failed");
        if (!HaveKey(keypool.vchPubKey.GetID()))
            throw runtime_error("ReserveKeyFromKeyPool() : unknown key in key pool");
        assert(keypool.vchPubKey.IsValid());
        printf("keypool reserve %"PRI64d"\n", nIndex);
    }
}

int64 CWallet::AddReserveKey(const CKeyPool& keypool)
{
    {
        LOCK2(cs_main, cs_wallet);
        CWalletDB walletdb(strWalletFile);

        int64 nIndex = 1 + *(--setKeyPool.end());
        if (!walletdb.WritePool(nIndex, keypool))
            throw runtime_error("AddReserveKey() : writing added key failed");
        setKeyPool.insert(nIndex);
        return nIndex;
    }
    return -1;
}

void CWallet::KeepKey(int64 nIndex)
{
    // Remove from key pool
    if (fFileBacked)
    {
        CWalletDB walletdb(strWalletFile);
        walletdb.ErasePool(nIndex);
    }
    printf("keypool keep %"PRI64d"\n", nIndex);
}

void CWallet::ReturnKey(int64 nIndex)
{
    // Return to key pool
    {
        LOCK(cs_wallet);
        setKeyPool.insert(nIndex);
    }
    printf("keypool return %"PRI64d"\n", nIndex);
}

bool CWallet::GetKeyFromPool(CPubKey& result, bool fAllowReuse)
{
    /* [MF] pool is going to die.
    int64 nIndex = 0;
    CKeyPool keypool;
    {
        LOCK(cs_wallet);
        ReserveKeyFromKeyPool(nIndex, keypool);
        if (nIndex == -1)
        {
            if (fAllowReuse && vchDefaultKey.IsValid())
            {
                result = vchDefaultKey;
                return true;
            }
            if (IsLocked()) return false;
            result = GenerateNewKey();
            return true;
        }
        KeepKey(nIndex);
        result = keypool.vchPubKey;
    }
    return true;
    */
    return false;
}

int64 CWallet::GetOldestKeyPoolTime()
{
    int64 nIndex = 0;
    CKeyPool keypool;
    ReserveKeyFromKeyPool(nIndex, keypool);
    if (nIndex == -1)
        return GetTime();
    ReturnKey(nIndex);
    return keypool.nTime;
}

set< set<CTxDestination> > CWallet::GetAddressGroupings()
{
    set< set<CTxDestination> > groupings;
    set<CTxDestination> grouping;

    BOOST_FOREACH(PAIRTYPE(uint256, CWalletTx) walletEntry, mapWallet)
    {
        CWalletTx *pcoin = &walletEntry.second;
/*
        if (pcoin->vin.size() > 0)
        {
            bool any_mine = false;
            // group all input addresses with each other
            BOOST_FOREACH(CTxIn txin, pcoin->vin)
            {
                CTxDestination address;
                if(!IsMine(txin))
                    continue;
                if(!ExtractDestination(mapWallet[txin.prevout.hash].vout[txin.prevout.n].scriptPubKey, address))
                    continue;
                grouping.insert(address);
                any_mine = true;
            }

            // group change with input addresses
            if (any_mine)
            {
               BOOST_FOREACH(CTxOut txout, pcoin->vout)
                   if (IsChange(txout))
                   {
                       CTxDestination txoutAddr;
                       if(!ExtractDestination(txout.scriptPubKey, txoutAddr))
                           continue;
                       grouping.insert(txoutAddr);
                   }
            }
            if (grouping.size() > 0)
            {
                groupings.insert(grouping);
                grouping.clear();
            }
        }

        // group lone addrs by themselves
        for (unsigned int i = 0; i < pcoin->vout.size(); i++)
            if (IsMine(pcoin->vout[i]))
            {
                CTxDestination address;
                if(!ExtractDestination(pcoin->vout[i].scriptPubKey, address))
                    continue;
                grouping.insert(address);
                groupings.insert(grouping);
                grouping.clear();
            }
            */
    }

    set< set<CTxDestination>* > uniqueGroupings; // a set of pointers to groups of addresses
    map< CTxDestination, set<CTxDestination>* > setmap;  // map addresses to the unique group containing it
    BOOST_FOREACH(set<CTxDestination> grouping, groupings)
    {
        // make a set of all the groups hit by this new group
        set< set<CTxDestination>* > hits;
        map< CTxDestination, set<CTxDestination>* >::iterator it;
        BOOST_FOREACH(CTxDestination address, grouping)
            if ((it = setmap.find(address)) != setmap.end())
                hits.insert((*it).second);

        // merge all hit groups into a new single group and delete old groups
        set<CTxDestination>* merged = new set<CTxDestination>(grouping);
        BOOST_FOREACH(set<CTxDestination>* hit, hits)
        {
            merged->insert(hit->begin(), hit->end());
            uniqueGroupings.erase(hit);
            delete hit;
        }
        uniqueGroupings.insert(merged);

        // update setmap
        BOOST_FOREACH(CTxDestination element, *merged)
            setmap[element] = merged;
    }

    set< set<CTxDestination> > ret;
    BOOST_FOREACH(set<CTxDestination>* uniqueGrouping, uniqueGroupings)
    {
        ret.insert(*uniqueGrouping);
        delete uniqueGrouping;
    }

    return ret;
}

bool CReserveKey::GetReservedKey(CPubKey& pubkey)
{
    if (nIndex == -1)
    {
        CKeyPool keypool;
        pwallet->ReserveKeyFromKeyPool(nIndex, keypool);
        if (nIndex != -1)
            vchPubKey = keypool.vchPubKey;
        else {
            if (pwallet->vchDefaultKey.IsValid()) {
                printf("CReserveKey::GetReservedKey(): Warning: Using default key instead of a new key, top up your keypool!");
                vchPubKey = pwallet->vchDefaultKey;
            } else
                return false;
        }
    }
    assert(vchPubKey.IsValid());
    pubkey = vchPubKey;
    return true;
}

void CReserveKey::KeepKey()
{
    if (nIndex != -1)
        pwallet->KeepKey(nIndex);
    nIndex = -1;
    vchPubKey = CPubKey();
}

void CReserveKey::ReturnKey()
{
    if (nIndex != -1)
        pwallet->ReturnKey(nIndex);
    nIndex = -1;
    vchPubKey = CPubKey();
}

void CWallet::GetAllReserveKeys(set<CKeyID>& setAddress) const
{
    setAddress.clear();

    CWalletDB walletdb(strWalletFile);

    LOCK2(cs_main, cs_wallet);
    BOOST_FOREACH(const int64& id, setKeyPool)
    {
        CKeyPool keypool;
        if (!walletdb.ReadPool(id, keypool))
            throw runtime_error("GetAllReserveKeyHashes() : read failed");
        assert(keypool.vchPubKey.IsValid());
        CKeyID keyID = keypool.vchPubKey.GetID();
        if (!HaveKey(keyID))
            throw runtime_error("GetAllReserveKeyHashes() : unknown key in key pool");
        setAddress.insert(keyID);
    }
}

void CWallet::UpdatedTransaction(const uint256 &hashTx)
{
    {
        LOCK(cs_wallet);
        // Only notify UI if this transaction is in this wallet
        map<uint256, CWalletTx>::const_iterator mi = mapWallet.find(hashTx);
        if (mi != mapWallet.end())
            NotifyTransactionChanged(this, hashTx, CT_UPDATED);
    }
}


void CWallet::GetKeyBirthTimes(std::map<CKeyID, int64> &mapKeyBirth) const {
    mapKeyBirth.clear();

    // get birth times for keys with metadata
    for (std::map<CKeyID, CKeyMetadata>::const_iterator it = mapKeyMetadata.begin(); it != mapKeyMetadata.end(); it++)
        if (it->second.nCreateTime)
            mapKeyBirth[it->first] = it->second.nCreateTime;

    // map in which we'll infer heights of other keys
    CBlockIndex *pindexMax = FindBlockByHeight(std::max(0, nBestHeight - 144)); // the tip can be reorganised; use a 144-block safety margin
    std::map<CKeyID, CBlockIndex*> mapKeyFirstBlock;
    std::set<CKeyID> setKeys;
    GetKeys(setKeys);
    BOOST_FOREACH(const CKeyID &keyid, setKeys) {
        if (mapKeyBirth.count(keyid) == 0)
            mapKeyFirstBlock[keyid] = pindexMax;
    }
    setKeys.clear();

    // if there are no such keys, we're done
    if (mapKeyFirstBlock.empty())
        return;
/*
    // find first block that affects those keys, if there are any left
    std::vector<CKeyID> vAffected;
    for (std::map<uint256, CWalletTx>::const_iterator it = mapWallet.begin(); it != mapWallet.end(); it++) {
        // iterate over all wallet transactions...
        const CWalletTx &wtx = (*it).second;
        std::map<uint256, CBlockIndex*>::const_iterator blit = mapBlockIndex.find(wtx.hashBlock);
        if (blit != mapBlockIndex.end() && blit->second->IsInMainChain()) {
            // ... which are already in a block
            int nHeight = blit->second->nHeight;
            BOOST_FOREACH(const CTxOut &txout, wtx.vout) {
                // iterate over all their outputs
                ::ExtractAffectedKeys(*this, txout.scriptPubKey, vAffected);
                BOOST_FOREACH(const CKeyID &keyid, vAffected) {
                    // ... and all their affected keys
                    std::map<CKeyID, CBlockIndex*>::iterator rit = mapKeyFirstBlock.find(keyid);
                    if (rit != mapKeyFirstBlock.end() && nHeight < rit->second->nHeight)
                        rit->second = blit->second;
                }
                vAffected.clear();
            }
        }
    }
*/
    // Extract block timestamps for those keys
    for (std::map<CKeyID, CBlockIndex*>::const_iterator it = mapKeyFirstBlock.begin(); it != mapKeyFirstBlock.end(); it++)
        mapKeyBirth[it->first] = it->second->nTime - 7200; // block times can be 2h off
}