#include <boost/assign/list_of.hpp>
#include "kernel.h"
-#include "db.h"
+#include "txdb.h"
using namespace std;
extern int nStakeMaxAge;
extern int nStakeTargetSpacing;
-// Modifier interval: time to elapse before new modifier is computed
-// Set to 6-hour for production network and 20-minute for test network
-unsigned int nModifierInterval = MODIFIER_INTERVAL;
+typedef std::map<int, unsigned int> MapModifierCheckpoints;
// Hard checkpoints of stake modifiers to ensure they are deterministic
static std::map<int, unsigned int> mapStakeModifierCheckpoints =
boost::assign::map_list_of
- ( 0, 0x0e00670bu )
- ( 6000, 0xb7cbc5d3u )
- ( 12661, 0x5d84115du )
+ ( 0, 0x0e00670bu )
+ ( 9690, 0x97dcdafau )
+ ( 12661, 0x5d84115du )
+ ( 37092, 0xd230afccu )
+ ( 44200, 0x05370164u )
+ ( 65000, 0xc8e7be6au )
+ ( 68600, 0x73a8cc4cu )
+ ( 92161, 0xe21a911au )
+ ( 98661, 0xd20c44d4u )
;
+// Hard checkpoints of stake modifiers to ensure they are deterministic (testNet)
+static std::map<int, unsigned int> mapStakeModifierCheckpointsTestNet =
+ boost::assign::map_list_of
+ ( 0, 0x0e00670bu )
+ ;
+
+// Get time weight
+int64 GetWeight(int64 nIntervalBeginning, int64 nIntervalEnd)
+{
+ // Kernel hash weight starts from 0 at the 30-day min age
+ // this change increases active coins participating the hash and helps
+ // to secure the network when proof-of-stake difficulty is low
+ //
+ // Maximum TimeWeight is 90 days.
+
+ return min(nIntervalEnd - nIntervalBeginning - nStakeMinAge, (int64)nStakeMaxAge);
+}
+
// Get the last stake modifier and its generation time from a given block
static bool GetLastStakeModifier(const CBlockIndex* pindex, uint64& nStakeModifier, int64& nModifierTime)
{
// select a block from the candidate blocks in vSortedByTimestamp, excluding
// already selected blocks in vSelectedBlocks, and with timestamp up to
// nSelectionIntervalStop.
-static bool SelectBlockFromCandidates(
- vector<pair<int64, uint256> >& vSortedByTimestamp,
- map<uint256, const CBlockIndex*>& mapSelectedBlocks,
- int64 nSelectionIntervalStop, uint64 nStakeModifierPrev,
- const CBlockIndex** pindexSelected)
+static bool SelectBlockFromCandidates(vector<pair<int64, uint256> >& vSortedByTimestamp, map<uint256, const CBlockIndex*>& mapSelectedBlocks,
+ int64 nSelectionIntervalStop, uint64 nStakeModifierPrev, const CBlockIndex** pindexSelected)
{
bool fSelected = false;
uint256 hashBest = 0;
// add the selected block from candidates to selected list
mapSelectedBlocks.insert(make_pair(pindex->GetBlockHash(), pindex));
if (fDebug && GetBoolArg("-printstakemodifier"))
- printf("ComputeNextStakeModifier: selected round %d stop=%s height=%d bit=%d\n",
- nRound, DateTimeStrFormat(nSelectionIntervalStop).c_str(), pindex->nHeight, pindex->GetStakeEntropyBit());
+ printf("ComputeNextStakeModifier: selected round %d stop=%s height=%d bit=%d\n", nRound, DateTimeStrFormat(nSelectionIntervalStop).c_str(), pindex->nHeight, pindex->GetStakeEntropyBit());
}
// Print selection map for visualization of the selected blocks
// this ensures that the chance of getting a coinstake is proportional to the
// amount of coin age one owns.
// The reason this hash is chosen is the following:
-// nStakeModifier:
-// (v0.3) scrambles computation to make it very difficult to precompute
-// future proof-of-stake at the time of the coin's confirmation
-// (v0.2) nBits (deprecated): encodes all past block timestamps
+// nStakeModifier: scrambles computation to make it very difficult to precompute
+// future proof-of-stake at the time of the coin's confirmation
// txPrev.block.nTime: prevent nodes from guessing a good timestamp to
// generate transaction for future advantage
// txPrev.offset: offset of txPrev inside block, to reduce the chance of
// quantities so as to generate blocks faster, degrading the system back into
// a proof-of-work situation.
//
-bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, unsigned int nTxPrevOffset, const CTransaction& txPrev, const COutPoint& prevout, unsigned int nTimeTx, uint256& hashProofOfStake, bool fPrintProofOfStake)
+bool CheckStakeKernelHash(unsigned int nBits, const CBlock& blockFrom, unsigned int nTxPrevOffset, const CTransaction& txPrev, const COutPoint& prevout, unsigned int nTimeTx, uint256& hashProofOfStake, uint256& targetProofOfStake, bool fPrintProofOfStake)
{
if (nTimeTx < txPrev.nTime) // Transaction timestamp violation
return error("CheckStakeKernelHash() : nTime violation");
bnTargetPerCoinDay.SetCompact(nBits);
int64 nValueIn = txPrev.vout[prevout.n].nValue;
- // v0.3 protocol kernel hash weight starts from 0 at the 30-day min age
- // this change increases active coins participating the hash and helps
- // to secure the network when proof-of-stake difficulty is low
- int64 nTimeWeight = min((int64)nTimeTx - txPrev.nTime, (int64)nStakeMaxAge) - nStakeMinAge;
- CBigNum bnCoinDayWeight = CBigNum(nValueIn) * nTimeWeight / COIN / (24 * 60 * 60);
+ uint256 hashBlockFrom = blockFrom.GetHash();
+
+ CBigNum bnCoinDayWeight = CBigNum(nValueIn) * GetWeight((int64)txPrev.nTime, (int64)nTimeTx) / COIN / (24 * 60 * 60);
+ targetProofOfStake = (bnCoinDayWeight * bnTargetPerCoinDay).getuint256();
// Calculate hash
CDataStream ss(SER_GETHASH, 0);
int nStakeModifierHeight = 0;
int64 nStakeModifierTime = 0;
- if (!GetKernelStakeModifier(blockFrom.GetHash(), nStakeModifier, nStakeModifierHeight, nStakeModifierTime, fPrintProofOfStake))
+ if (!GetKernelStakeModifier(hashBlockFrom, nStakeModifier, nStakeModifierHeight, nStakeModifierTime, fPrintProofOfStake))
return false;
ss << nStakeModifier;
printf("CheckStakeKernelHash() : using modifier 0x%016"PRI64x" at height=%d timestamp=%s for block from height=%d timestamp=%s\n",
nStakeModifier, nStakeModifierHeight,
DateTimeStrFormat(nStakeModifierTime).c_str(),
- mapBlockIndex[blockFrom.GetHash()]->nHeight,
+ mapBlockIndex[hashBlockFrom]->nHeight,
DateTimeStrFormat(blockFrom.GetBlockTime()).c_str());
- printf("CheckStakeKernelHash() : check protocol=%s modifier=0x%016"PRI64x" nTimeBlockFrom=%u nTxPrevOffset=%u nTimeTxPrev=%u nPrevout=%u nTimeTx=%u hashProof=%s\n",
- "0.3",
+ printf("CheckStakeKernelHash() : check modifier=0x%016"PRI64x" nTimeBlockFrom=%u nTxPrevOffset=%u nTimeTxPrev=%u nPrevout=%u nTimeTx=%u hashProof=%s\n",
nStakeModifier,
nTimeBlockFrom, nTxPrevOffset, txPrev.nTime, prevout.n, nTimeTx,
hashProofOfStake.ToString().c_str());
printf("CheckStakeKernelHash() : using modifier 0x%016"PRI64x" at height=%d timestamp=%s for block from height=%d timestamp=%s\n",
nStakeModifier, nStakeModifierHeight,
DateTimeStrFormat(nStakeModifierTime).c_str(),
- mapBlockIndex[blockFrom.GetHash()]->nHeight,
+ mapBlockIndex[hashBlockFrom]->nHeight,
DateTimeStrFormat(blockFrom.GetBlockTime()).c_str());
- printf("CheckStakeKernelHash() : pass protocol=%s modifier=0x%016"PRI64x" nTimeBlockFrom=%u nTxPrevOffset=%u nTimeTxPrev=%u nPrevout=%u nTimeTx=%u hashProof=%s\n",
- "0.3",
+ printf("CheckStakeKernelHash() : pass modifier=0x%016"PRI64x" nTimeBlockFrom=%u nTxPrevOffset=%u nTimeTxPrev=%u nPrevout=%u nTimeTx=%u hashProof=%s\n",
nStakeModifier,
nTimeBlockFrom, nTxPrevOffset, txPrev.nTime, prevout.n, nTimeTx,
hashProofOfStake.ToString().c_str());
}
// Check kernel hash target and coinstake signature
-bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hashProofOfStake)
+bool CheckProofOfStake(const CTransaction& tx, unsigned int nBits, uint256& hashProofOfStake, uint256& targetProofOfStake)
{
if (!tx.IsCoinStake())
return error("CheckProofOfStake() : called on non-coinstake %s", tx.GetHash().ToString().c_str());
CTxIndex txindex;
if (!txPrev.ReadFromDisk(txdb, txin.prevout, txindex))
return tx.DoS(1, error("CheckProofOfStake() : INFO: read txPrev failed")); // previous transaction not in main chain, may occur during initial download
- txdb.Close();
// Verify signature
if (!VerifySignature(txPrev, tx, 0, true, 0))
if (!block.ReadFromDisk(txindex.pos.nFile, txindex.pos.nBlockPos, false))
return fDebug? error("CheckProofOfStake() : read block failed") : false; // unable to read block of previous transaction
- if (!CheckStakeKernelHash(nBits, block, txindex.pos.nTxPos - txindex.pos.nBlockPos, txPrev, txin.prevout, tx.nTime, hashProofOfStake, fDebug))
+ if (!CheckStakeKernelHash(nBits, block, txindex.pos.nTxPos - txindex.pos.nBlockPos, txPrev, txin.prevout, tx.nTime, hashProofOfStake, targetProofOfStake, fDebug))
return tx.DoS(1, error("CheckProofOfStake() : INFO: check kernel failed on coinstake %s, hashProof=%s", tx.GetHash().ToString().c_str(), hashProofOfStake.ToString().c_str())); // may occur during initial download or if behind on block chain sync
return true;
}
-// Check whether the coinstake timestamp meets protocol
-bool CheckCoinStakeTimestamp(int64 nTimeBlock, int64 nTimeTx)
-{
- // v0.3 protocol
- return (nTimeBlock == nTimeTx);
-}
-
// Get stake modifier checksum
unsigned int GetStakeModifierChecksum(const CBlockIndex* pindex)
{
- assert (pindex->pprev || pindex->GetBlockHash() == hashGenesisBlock);
+ assert (pindex->pprev || pindex->GetBlockHash() == (!fTestNet ? hashGenesisBlock : hashGenesisBlockTestNet));
// Hash previous checksum with flags, hashProofOfStake and nStakeModifier
CDataStream ss(SER_GETHASH, 0);
if (pindex->pprev)
// Check stake modifier hard checkpoints
bool CheckStakeModifierCheckpoints(int nHeight, unsigned int nStakeModifierChecksum)
{
- if (fTestNet) return true; // Testnet has no checkpoints
- if (mapStakeModifierCheckpoints.count(nHeight))
- return nStakeModifierChecksum == mapStakeModifierCheckpoints[nHeight];
+ MapModifierCheckpoints& checkpoints = (fTestNet ? mapStakeModifierCheckpointsTestNet : mapStakeModifierCheckpoints);
+
+ if (checkpoints.count(nHeight))
+ return nStakeModifierChecksum == checkpoints[nHeight];
return true;
}
git://git.novaco.in / novacoin.git / blobdiff