Ejemplo n.º 1
0
bool CTxDB::LoadBlockIndex()
{
    if (!LoadBlockIndexGuts())
        return false;

    if (fRequestShutdown)
        return true;

    // Calculate bnChainWork
    vector<pair<int, CBlockIndex*> > vSortedByHeight;
    vSortedByHeight.reserve(mapBlockIndex.size());
    BOOST_FOREACH(const PAIRTYPE(uint256, CBlockIndex*)& item, mapBlockIndex)
    {
        CBlockIndex* pindex = item.second;
        vSortedByHeight.push_back(make_pair(pindex->nHeight, pindex));
    }
    sort(vSortedByHeight.begin(), vSortedByHeight.end());
    BOOST_FOREACH(const PAIRTYPE(int, CBlockIndex*)& item, vSortedByHeight)
    {
        CBlockIndex* pindex = item.second;
        pindex->bnChainWork = (pindex->pprev ? pindex->pprev->bnChainWork : 0) + pindex->GetBlockWork();
    }

    // Load hashBestChain pointer to end of best chain
    if (!ReadHashBestChain(hashBestChain))
    {
        if (pindexGenesisBlock == NULL)
            return true;
        return error("CTxDB::LoadBlockIndex() : hashBestChain not loaded");
    }
    if (!mapBlockIndex.count(hashBestChain))
        return error("CTxDB::LoadBlockIndex() : hashBestChain not found in the block index");
    pindexBest = mapBlockIndex[hashBestChain];
    nBestHeight = pindexBest->nHeight;
    bnBestChainWork = pindexBest->bnChainWork;
    printf("LoadBlockIndex(): hashBestChain=%s  height=%d  date=%s\n",
      hashBestChain.ToString().substr(0,20).c_str(), nBestHeight,
      DateTimeStrFormat("%x %H:%M:%S", pindexBest->GetBlockTime()).c_str());

    // Load bnBestInvalidWork, OK if it doesn't exist
    ReadBestInvalidWork(bnBestInvalidWork);

    // Verify blocks in the best chain
    int nCheckLevel = GetArg("-checklevel", 1);
    int nCheckDepth = GetArg( "-checkblocks", 2500);
    if (nCheckDepth == 0)
        nCheckDepth = 1000000000; // suffices until the year 19000
    if (nCheckDepth > nBestHeight)
        nCheckDepth = nBestHeight;
    printf("Verifying last %i blocks at level %i\n", nCheckDepth, nCheckLevel);
    CBlockIndex* pindexFork = NULL;
    map<pair<unsigned int, unsigned int>, CBlockIndex*> mapBlockPos;
    for (CBlockIndex* pindex = pindexBest; pindex && pindex->pprev; pindex = pindex->pprev)
    {
        if (fRequestShutdown || pindex->nHeight < nBestHeight-nCheckDepth)
            break;
        CBlock block;
        if (!block.ReadFromDisk(pindex))
            return error("LoadBlockIndex() : block.ReadFromDisk failed");
        // check level 1: verify block validity
        if (nCheckLevel>0 && !block.CheckBlock())
        {
            printf("LoadBlockIndex() : *** found bad block at %d, hash=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString().c_str());
            pindexFork = pindex->pprev;
        }
        // check level 2: verify transaction index validity
        if (nCheckLevel>1)
        {
            pair<unsigned int, unsigned int> pos = make_pair(pindex->nFile, pindex->nBlockPos);
            mapBlockPos[pos] = pindex;
            BOOST_FOREACH(const CTransaction &tx, block.vtx)
            {
                uint256 hashTx = tx.GetHash();
                CTxIndex txindex;
                if (ReadTxIndex(hashTx, txindex))
                {
                    // check level 3: checker transaction hashes
                    if (nCheckLevel>2 || pindex->nFile != txindex.pos.nFile || pindex->nBlockPos != txindex.pos.nBlockPos)
                    {
                        // either an error or a duplicate transaction
                        CTransaction txFound;
                        if (!txFound.ReadFromDisk(txindex.pos))
                        {
                            printf("LoadBlockIndex() : *** cannot read mislocated transaction %s\n", hashTx.ToString().c_str());
                            pindexFork = pindex->pprev;
                        }
                        else
                            if (txFound.GetHash() != hashTx) // not a duplicate tx
                            {
                                printf("LoadBlockIndex(): *** invalid tx position for %s\n", hashTx.ToString().c_str());
                                pindexFork = pindex->pprev;
                            }
                    }
                    // check level 4: check whether spent txouts were spent within the main chain
                    unsigned int nOutput = 0;
                    if (nCheckLevel>3)
                    {
                        BOOST_FOREACH(const CDiskTxPos &txpos, txindex.vSpent)
                        {
                            if (!txpos.IsNull())
                            {
                                pair<unsigned int, unsigned int> posFind = make_pair(txpos.nFile, txpos.nBlockPos);
                                if (!mapBlockPos.count(posFind))
                                {
                                    printf("LoadBlockIndex(): *** found bad spend at %d, hashBlock=%s, hashTx=%s\n", pindex->nHeight, pindex->GetBlockHash().ToString().c_str(), hashTx.ToString().c_str());
                                    pindexFork = pindex->pprev;
                                }
                                // check level 6: check whether spent txouts were spent by a valid transaction that consume them
                                if (nCheckLevel>5)
                                {
                                    CTransaction txSpend;
                                    if (!txSpend.ReadFromDisk(txpos))
                                    {
                                        printf("LoadBlockIndex(): *** cannot read spending transaction of %s:%i from disk\n", hashTx.ToString().c_str(), nOutput);
                                        pindexFork = pindex->pprev;
                                    }
                                    else if (!txSpend.CheckTransaction())
                                    {
                                        printf("LoadBlockIndex(): *** spending transaction of %s:%i is invalid\n", hashTx.ToString().c_str(), nOutput);
                                        pindexFork = pindex->pprev;
                                    }
                                    else
                                    {
                                        bool fFound = false;
                                        BOOST_FOREACH(const CTxIn &txin, txSpend.vin)
                                            if (txin.prevout.hash == hashTx && txin.prevout.n == nOutput)
                                                fFound = true;
                                        if (!fFound)
                                        {
                                            printf("LoadBlockIndex(): *** spending transaction of %s:%i does not spend it\n", hashTx.ToString().c_str(), nOutput);
                                            pindexFork = pindex->pprev;
                                        }
                                    }
                                }
                            }
                            nOutput++;
                        }
                    }
                }