Exemplo n.º 1
0
func TestLotteryNumSelection(t *testing.T) {
	// Test finding ticket indexes.
	seed := chainhash.HashFuncB([]byte{0x01})
	prng := stake.NewHash256PRNG(seed)
	ticketsInPool := int64(56789)
	tooFewTickets := int64(4)
	justEnoughTickets := int64(5)
	ticketsPerBlock := 5

	_, err := stake.FindTicketIdxs(tooFewTickets, ticketsPerBlock, prng)
	if err == nil {
		t.Errorf("got unexpected no error for FindTicketIdxs too few tickets " +
			"test")
	}

	tickets, err := stake.FindTicketIdxs(ticketsInPool, ticketsPerBlock, prng)
	if err != nil {
		t.Errorf("got unexpected error for FindTicketIdxs 1 test")
	}
	ticketsExp := []int{34850, 8346, 27636, 54482, 25482}
	if !reflect.DeepEqual(ticketsExp, tickets) {
		t.Errorf("Unexpected tickets selected; got %v, want %v", tickets,
			ticketsExp)
	}

	// Ensure that it can find all suitable ticket numbers in a small
	// bucket of tickets.
	tickets, err = stake.FindTicketIdxs(justEnoughTickets, ticketsPerBlock, prng)
	if err != nil {
		t.Errorf("got unexpected error for FindTicketIdxs 2 test")
	}
	ticketsExp = []int{3, 0, 4, 2, 1}
	if !reflect.DeepEqual(ticketsExp, tickets) {
		t.Errorf("Unexpected tickets selected; got %v, want %v", tickets,
			ticketsExp)
	}

	lastHashExp, _ := chainhash.NewHashFromStr("e97ce54aea63a883a82871e752c" +
		"6ec3c5731fffc63dafc3767c06861b0b2fa65")
	lastHash := prng.StateHash()
	if *lastHashExp != lastHash {
		t.Errorf("expected final state of %v, got %v", lastHashExp, lastHash)
	}
}
Exemplo n.º 2
0
func TestTicketDB(t *testing.T) {
	// Declare some useful variables
	testBCHeight := int64(168)

	// Set up a DB
	database, err := database.CreateDB("leveldb", "ticketdb_test")
	if err != nil {
		t.Errorf("Db create error: %v", err.Error())
	}

	// Make a new tmdb to fill with dummy live and used tickets
	var tmdb stake.TicketDB
	tmdb.Initialize(simNetParams, database)

	filename := filepath.Join("..", "/../blockchain/testdata", "blocks0to168.bz2")
	fi, err := os.Open(filename)
	bcStream := bzip2.NewReader(fi)
	defer fi.Close()

	// Create a buffer of the read file
	bcBuf := new(bytes.Buffer)
	bcBuf.ReadFrom(bcStream)

	// Create decoder from the buffer and a map to store the data
	bcDecoder := gob.NewDecoder(bcBuf)
	blockchain := make(map[int64][]byte)

	// Decode the blockchain into the map
	if err := bcDecoder.Decode(&blockchain); err != nil {
		t.Errorf("error decoding test blockchain")
	}

	var CopyOfMapsAtBlock50, CopyOfMapsAtBlock168 stake.TicketMaps
	var ticketsToSpendIn167 []chainhash.Hash
	var sortedTickets167 []*stake.TicketData

	for i := int64(0); i <= testBCHeight; i++ {
		block, err := dcrutil.NewBlockFromBytes(blockchain[i])
		if err != nil {
			t.Errorf("block deserialization error on block %v", i)
		}
		block.SetHeight(i)
		database.InsertBlock(block)
		tmdb.InsertBlock(block)

		if i == 50 {
			// Create snapshot of tmdb at block 50
			CopyOfMapsAtBlock50, err = cloneTicketDB(&tmdb)
			if err != nil {
				t.Errorf("db cloning at block 50 failure! %v", err)
			}
		}

		// Test to make sure that ticket selection is working correctly.
		if i == 167 {
			// Sort the entire list of tickets lexicographically by sorting
			// each bucket and then appending it to the list. Then store it
			// to use in the next block.
			totalTickets := 0
			sortedSlice := make([]*stake.TicketData, 0)
			for i := 0; i < stake.BucketsSize; i++ {
				tix, err := tmdb.DumpLiveTickets(uint8(i))
				if err != nil {
					t.Errorf("error dumping live tickets")
				}
				mapLen := len(tix)
				totalTickets += mapLen
				tempTdSlice := stake.NewTicketDataSlice(mapLen)
				itr := 0 // Iterator
				for _, td := range tix {
					tempTdSlice[itr] = td
					itr++
				}
				sort.Sort(tempTdSlice)
				sortedSlice = append(sortedSlice, tempTdSlice...)
			}
			sortedTickets167 = sortedSlice
		}

		if i == 168 {
			parentBlock, err := dcrutil.NewBlockFromBytes(blockchain[i-1])
			if err != nil {
				t.Errorf("block deserialization error on block %v", i-1)
			}
			pbhB, err := parentBlock.MsgBlock().Header.Bytes()
			if err != nil {
				t.Errorf("block header serialization error")
			}
			prng := stake.NewHash256PRNG(pbhB)
			ts, err := stake.FindTicketIdxs(int64(len(sortedTickets167)),
				int(simNetParams.TicketsPerBlock), prng)
			if err != nil {
				t.Errorf("failure on FindTicketIdxs")
			}
			for _, idx := range ts {
				ticketsToSpendIn167 =
					append(ticketsToSpendIn167, sortedTickets167[idx].SStxHash)
			}

			// Make sure that the tickets that were supposed to be spent or
			// missed were.
			spentTix, err := tmdb.DumpSpentTickets(i)
			if err != nil {
				t.Errorf("DumpSpentTickets failure")
			}
			for _, h := range ticketsToSpendIn167 {
				if _, ok := spentTix[h]; !ok {
					t.Errorf("missing ticket %v that should have been missed "+
						"or spent in block %v", h, i)
				}
			}

			// Create snapshot of tmdb at block 168
			CopyOfMapsAtBlock168, err = cloneTicketDB(&tmdb)
			if err != nil {
				t.Errorf("db cloning at block 168 failure! %v", err)
			}
		}
	}

	// Remove five blocks from HEAD~1
	_, _, _, err = tmdb.RemoveBlockToHeight(50)
	if err != nil {
		t.Errorf("error: %v", err)
	}

	// Test if the roll back was symmetric to the earlier snapshot
	if !reflect.DeepEqual(tmdb.DumpMapsPointer(), CopyOfMapsAtBlock50) {
		t.Errorf("The td did not restore to a previous block height correctly!")
	}

	// Test rescanning a ticket db
	err = tmdb.RescanTicketDB()
	if err != nil {
		t.Errorf("rescanticketdb err: %v", err.Error())
	}

	// Test if the db file storage was symmetric to the earlier snapshot
	if !reflect.DeepEqual(tmdb.DumpMapsPointer(), CopyOfMapsAtBlock168) {
		t.Errorf("The td did not rescan to HEAD correctly!")
	}

	err = os.Mkdir("testdata/", os.FileMode(0700))
	if err != nil {
		t.Error(err)
	}

	// Store the ticket db to disk
	err = tmdb.Store("testdata/", "testtmdb")
	if err != nil {
		t.Errorf("error: %v", err)
	}

	var tmdb2 stake.TicketDB
	err = tmdb2.LoadTicketDBs("testdata/", "testtmdb", simNetParams, database)
	if err != nil {
		t.Errorf("error: %v", err)
	}

	// Test if the db file storage was symmetric to previously rescanned one
	if !reflect.DeepEqual(tmdb.DumpMapsPointer(), tmdb2.DumpMapsPointer()) {
		t.Errorf("The td did not rescan to a previous block height correctly!")
	}

	tmdb2.Close()

	// Test dumping missing tickets from block 152
	missedIn152, _ := chainhash.NewHashFromStr(
		"84f7f866b0af1cc278cb8e0b2b76024a07542512c76487c83628c14c650de4fa")

	tmdb.RemoveBlockToHeight(152)

	missedTix, err := tmdb.DumpMissedTickets()
	if err != nil {
		t.Errorf("err dumping missed tix: %v", err.Error())
	}

	if _, exists := missedTix[*missedIn152]; !exists {
		t.Errorf("couldn't finding missed tx 1 %v in tmdb @ block 152!",
			missedIn152)
	}

	tmdb.RescanTicketDB()

	// Make sure that the revoked map contains the revoked tx
	revokedSlice := []*chainhash.Hash{missedIn152}

	revokedTix, err := tmdb.DumpRevokedTickets()
	if err != nil {
		t.Errorf("err dumping missed tix: %v", err.Error())
	}

	if len(revokedTix) != 1 {
		t.Errorf("revoked ticket map is wrong len, got %v, want %v",
			len(revokedTix), 1)
	}

	_, wasMissedIn152 := revokedTix[*revokedSlice[0]]
	ticketsRevoked := wasMissedIn152
	if !ticketsRevoked {
		t.Errorf("revoked ticket map did not include tickets missed in " +
			"block 152 and later revoked")
	}

	database.Close()
	tmdb.Close()

	os.RemoveAll("ticketdb_test")
	os.Remove("./ticketdb_test.ver")
	os.Remove("testdata/testtmdb")
	os.Remove("testdata")
}
Exemplo n.º 3
0
// getWinningTicketsWithStore is a helper function that returns winning tickets
// along with the ticket pool size and transaction store for the given node.
// Note that this function evaluates the lottery data predominantly for mining
// purposes; that is, it retrieves the lottery data which needs to go into
// the next block when mining on top of this block.
// This function is NOT safe for concurrent access.
func (b *BlockChain) getWinningTicketsWithStore(node *blockNode) ([]chainhash.Hash,
	int, [6]byte, TicketStore, error) {
	if node.height < b.chainParams.StakeEnabledHeight {
		return []chainhash.Hash{}, 0, [6]byte{}, nil, nil
	}

	evalLotteryWinners := false
	if node.height >= b.chainParams.StakeValidationHeight-1 {
		evalLotteryWinners = true
	}

	block, err := b.getBlockFromHash(node.hash)
	if err != nil {
		return nil, 0, [6]byte{}, nil, err
	}

	headerB, err := node.header.Bytes()
	if err != nil {
		return nil, 0, [6]byte{}, nil, err
	}

	ticketStore, err := b.fetchTicketStore(node)
	if err != nil {
		return nil, 0, [6]byte{}, nil,
			fmt.Errorf("Failed to generate ticket store for node %v; "+
				"error given: %v", node.hash, err)
	}

	if ticketStore != nil {
		// We need the viewpoint of spendable tickets given that the
		// current block was actually added.
		err = b.connectTickets(ticketStore, node, block)
		if err != nil {
			return nil, 0, [6]byte{}, nil, err
		}
	}

	// Sort the entire list of tickets lexicographically by sorting
	// each bucket and then appending it to the list.
	tpdBucketMap := make(map[uint8][]*TicketPatchData)
	for _, tpd := range ticketStore {
		// Bucket does not exist.
		if _, ok := tpdBucketMap[tpd.td.Prefix]; !ok {
			tpdBucketMap[tpd.td.Prefix] = make([]*TicketPatchData, 1)
			tpdBucketMap[tpd.td.Prefix][0] = tpd
		} else {
			// Bucket exists.
			data := tpdBucketMap[tpd.td.Prefix]
			tpdBucketMap[tpd.td.Prefix] = append(data, tpd)
		}
	}
	totalTickets := 0
	sortedSlice := make([]*stake.TicketData, 0)
	for i := 0; i < stake.BucketsSize; i++ {
		ltb, err := b.GenerateLiveTicketBucket(ticketStore, tpdBucketMap,
			uint8(i))
		if err != nil {
			h := node.hash
			str := fmt.Sprintf("Failed to generate a live ticket bucket "+
				"to evaluate the lottery data for node %v, height %v! Error "+
				"given: %v",
				h,
				node.height,
				err.Error())
			return nil, 0, [6]byte{}, nil, fmt.Errorf(str)
		}
		mapLen := len(ltb)

		tempTdSlice := stake.NewTicketDataSlice(mapLen)
		itr := 0 // Iterator
		for _, td := range ltb {
			tempTdSlice[itr] = td
			itr++
			totalTickets++
		}
		sort.Sort(tempTdSlice)
		sortedSlice = append(sortedSlice, tempTdSlice...)
	}

	// Use the parent block's header to seed a PRNG that picks the
	// lottery winners.
	winningTickets := make([]chainhash.Hash, 0)
	var finalState [6]byte
	stateBuffer := make([]byte, 0,
		(b.chainParams.TicketsPerBlock+1)*chainhash.HashSize)
	if evalLotteryWinners {
		ticketsPerBlock := int(b.chainParams.TicketsPerBlock)
		prng := stake.NewHash256PRNG(headerB)
		ts, err := stake.FindTicketIdxs(int64(totalTickets), ticketsPerBlock, prng)
		if err != nil {
			return nil, 0, [6]byte{}, nil, err
		}
		for _, idx := range ts {
			winningTickets = append(winningTickets, sortedSlice[idx].SStxHash)
			stateBuffer = append(stateBuffer, sortedSlice[idx].SStxHash[:]...)
		}

		lastHash := prng.StateHash()
		stateBuffer = append(stateBuffer, lastHash[:]...)
		copy(finalState[:], chainhash.HashFuncB(stateBuffer)[0:6])
	}

	return winningTickets, totalTickets, finalState, ticketStore, nil
}
Exemplo n.º 4
0
// connectTickets updates the passed map by removing removing any tickets
// from the ticket pool that have been considered spent or missed in this block
// according to the block header. Then, it connects all the newly mature tickets
// to the passed map.
func (b *BlockChain) connectTickets(tixStore TicketStore,
	node *blockNode,
	block *dcrutil.Block) error {
	if tixStore == nil {
		return fmt.Errorf("nil ticket store!")
	}

	// Nothing to do if tickets haven't yet possibly matured.
	height := node.height
	if height < b.chainParams.StakeEnabledHeight {
		return nil
	}

	parentBlock, err := b.GetBlockFromHash(node.parentHash)
	if err != nil {
		return err
	}

	revocations := node.header.Revocations

	tM := int64(b.chainParams.TicketMaturity)

	// Skip a number of validation steps before we requiring chain
	// voting.
	if node.height >= b.chainParams.StakeValidationHeight {
		regularTxTreeValid := dcrutil.IsFlagSet16(node.header.VoteBits,
			dcrutil.BlockValid)
		thisNodeStakeViewpoint := ViewpointPrevInvalidStake
		if regularTxTreeValid {
			thisNodeStakeViewpoint = ViewpointPrevValidStake
		}

		// We need the missed tickets bucket from the original perspective of
		// the node.
		missedTickets, err := b.GenerateMissedTickets(tixStore)
		if err != nil {
			return err
		}

		// TxStore at blockchain HEAD + TxTreeRegular of prevBlock (if
		// validated) for this node.
		txInputStoreStake, err := b.fetchInputTransactions(node, block,
			thisNodeStakeViewpoint)
		if err != nil {
			errStr := fmt.Sprintf("fetchInputTransactions failed for incoming "+
				"node %v; error given: %v", node.hash, err)
			return errors.New(errStr)
		}

		// PART 1: Spend/miss winner tickets

		// Iterate through all the SSGen (vote) tx in the block and add them to
		// a map of tickets that were actually used.
		spentTicketsFromBlock := make(map[chainhash.Hash]bool)
		numberOfSSgen := 0
		for _, staketx := range block.STransactions() {
			if is, _ := stake.IsSSGen(staketx); is {
				msgTx := staketx.MsgTx()
				sstxIn := msgTx.TxIn[1] // sstx input
				sstxHash := sstxIn.PreviousOutPoint.Hash

				originTx, exists := txInputStoreStake[sstxHash]
				if !exists {
					str := fmt.Sprintf("unable to find input transaction "+
						"%v for transaction %v", sstxHash, staketx.Sha())
					return ruleError(ErrMissingTx, str)
				}

				sstxHeight := originTx.BlockHeight

				// Check maturity of ticket; we can only spend the ticket after it
				// hits maturity at height + tM + 1.
				if (height - sstxHeight) < (tM + 1) {
					blockSha := block.Sha()
					errStr := fmt.Sprintf("Error: A ticket spend as an SSGen in "+
						"block height %v was immature! Block sha %v",
						height,
						blockSha)
					return errors.New(errStr)
				}

				// Fill out the ticket data.
				spentTicketsFromBlock[sstxHash] = true
				numberOfSSgen++
			}
		}

		// Obtain the TicketsPerBlock many tickets that were selected this round,
		// then check these against the tickets that were actually used to make
		// sure that any SSGen actually match the selected tickets. Commit the
		// spent or missed tickets to the ticket store after.
		spentAndMissedTickets := make(TicketStore)
		tixSpent := 0
		tixMissed := 0

		// Sort the entire list of tickets lexicographically by sorting
		// each bucket and then appending it to the list. Start by generating
		// a prefix matched map of tickets to speed up the lookup.
		tpdBucketMap := make(map[uint8][]*TicketPatchData)
		for _, tpd := range tixStore {
			// Bucket does not exist.
			if _, ok := tpdBucketMap[tpd.td.Prefix]; !ok {
				tpdBucketMap[tpd.td.Prefix] = make([]*TicketPatchData, 1)
				tpdBucketMap[tpd.td.Prefix][0] = tpd
			} else {
				// Bucket exists.
				data := tpdBucketMap[tpd.td.Prefix]
				tpdBucketMap[tpd.td.Prefix] = append(data, tpd)
			}
		}
		totalTickets := 0
		sortedSlice := make([]*stake.TicketData, 0)
		for i := 0; i < stake.BucketsSize; i++ {
			ltb, err := b.GenerateLiveTicketBucket(tixStore, tpdBucketMap,
				uint8(i))
			if err != nil {
				h := node.hash
				str := fmt.Sprintf("Failed to generate live ticket bucket "+
					"%v for node %v, height %v! Error: %v",
					i,
					h,
					node.height,
					err.Error())
				return fmt.Errorf(str)
			}
			mapLen := len(ltb)

			tempTdSlice := stake.NewTicketDataSlice(mapLen)
			itr := 0 // Iterator
			for _, td := range ltb {
				tempTdSlice[itr] = td
				itr++
				totalTickets++
			}
			sort.Sort(tempTdSlice)
			sortedSlice = append(sortedSlice, tempTdSlice...)
		}

		// Use the parent block's header to seed a PRNG that picks the
		// lottery winners.
		ticketsPerBlock := int(b.chainParams.TicketsPerBlock)
		pbhB, err := parentBlock.MsgBlock().Header.Bytes()
		if err != nil {
			return err
		}
		prng := stake.NewHash256PRNG(pbhB)
		ts, err := stake.FindTicketIdxs(int64(totalTickets), ticketsPerBlock, prng)
		if err != nil {
			return err
		}

		ticketsToSpendOrMiss := make([]*stake.TicketData, ticketsPerBlock,
			ticketsPerBlock)
		for i, idx := range ts {
			ticketsToSpendOrMiss[i] = sortedSlice[idx]
		}

		// Spend or miss these tickets by checking for their existence in the
		// passed spentTicketsFromBlock map.
		for _, ticket := range ticketsToSpendOrMiss {
			// Move the ticket from active tickets map into the used tickets
			// map if the ticket was spent.
			wasSpent, _ := spentTicketsFromBlock[ticket.SStxHash]

			if wasSpent {
				tpd := NewTicketPatchData(ticket, TiSpent, nil)
				spentAndMissedTickets[ticket.SStxHash] = tpd
				tixSpent++
			} else { // Ticket missed being spent and --> false or nil
				tpd := NewTicketPatchData(ticket, TiMissed, nil)
				spentAndMissedTickets[ticket.SStxHash] = tpd
				tixMissed++
			}
		}

		// This error is thrown if for some reason there exists an SSGen in
		// the block that doesn't spend a ticket from the eligible list of
		// tickets, thus making it invalid.
		if tixSpent != numberOfSSgen {
			errStr := fmt.Sprintf("an invalid number %v "+
				"tickets was spent, but %v many tickets should "+
				"have been spent!", tixSpent, numberOfSSgen)
			return errors.New(errStr)
		}

		if tixMissed != (ticketsPerBlock - numberOfSSgen) {
			errStr := fmt.Sprintf("an invalid number %v "+
				"tickets was missed, but %v many tickets should "+
				"have been missed!", tixMissed,
				ticketsPerBlock-numberOfSSgen)
			return errors.New(errStr)
		}

		if (tixSpent + tixMissed) != int(b.chainParams.TicketsPerBlock) {
			errStr := fmt.Sprintf("an invalid number %v "+
				"tickets was spent and missed, but TicketsPerBlock %v many "+
				"tickets should have been spent!", tixSpent,
				ticketsPerBlock)
			return errors.New(errStr)
		}

		// Calculate all the tickets expiring this block and mark them as missed.
		tpdBucketMap = make(map[uint8][]*TicketPatchData)
		for _, tpd := range tixStore {
			// Bucket does not exist.
			if _, ok := tpdBucketMap[tpd.td.Prefix]; !ok {
				tpdBucketMap[tpd.td.Prefix] = make([]*TicketPatchData, 1)
				tpdBucketMap[tpd.td.Prefix][0] = tpd
			} else {
				// Bucket exists.
				data := tpdBucketMap[tpd.td.Prefix]
				tpdBucketMap[tpd.td.Prefix] = append(data, tpd)
			}
		}
		toExpireHeight := node.height - int64(b.chainParams.TicketExpiry)
		if !(toExpireHeight < int64(b.chainParams.StakeEnabledHeight)) {
			for i := 0; i < stake.BucketsSize; i++ {
				// Generate the live ticket bucket.
				ltb, err := b.GenerateLiveTicketBucket(tixStore,
					tpdBucketMap, uint8(i))
				if err != nil {
					return err
				}

				for _, ticket := range ltb {
					if ticket.BlockHeight == toExpireHeight {
						tpd := NewTicketPatchData(ticket, TiMissed, nil)
						spentAndMissedTickets[ticket.SStxHash] = tpd
					}
				}
			}
		}

		// Merge the ticket store patch containing the spent and missed tickets
		// with the ticket store.
		for hash, tpd := range spentAndMissedTickets {
			tixStore[hash] = tpd
		}

		// At this point our tixStore now contains all the spent and missed tx
		// as per this block.

		// PART 2: Remove tickets that were missed and are now revoked.

		// Iterate through all the SSGen (vote) tx in the block and add them to
		// a map of tickets that were actually used.
		revocationsFromBlock := make(map[chainhash.Hash]struct{})
		numberOfSSRtx := 0
		for _, staketx := range block.STransactions() {
			if is, _ := stake.IsSSRtx(staketx); is {
				msgTx := staketx.MsgTx()
				sstxIn := msgTx.TxIn[0] // sstx input
				sstxHash := sstxIn.PreviousOutPoint.Hash

				// Fill out the ticket data.
				revocationsFromBlock[sstxHash] = struct{}{}
				numberOfSSRtx++
			}
		}

		if numberOfSSRtx != int(revocations) {
			errStr := fmt.Sprintf("an invalid revocations %v was calculated "+
				"the block header indicates %v instead", numberOfSSRtx,
				revocations)
			return errors.New(errStr)
		}

		// Lookup the missed ticket. If we find it in the patch data,
		// modify the patch data so that it doesn't exist.
		// Otherwise, just modify load the missed ticket data from
		// the ticket db and create patch data based on that.
		for hash, _ := range revocationsFromBlock {
			ticketWasMissed := false
			if td, is := missedTickets[hash]; is {
				maturedHeight := td.BlockHeight

				// Check maturity of ticket; we can only spend the ticket after it
				// hits maturity at height + tM + 2.
				if height < maturedHeight+2 {
					blockSha := block.Sha()
					errStr := fmt.Sprintf("Error: A ticket spend as an "+
						"SSRtx in block height %v was immature! Block sha %v",
						height,
						blockSha)
					return errors.New(errStr)
				}

				ticketWasMissed = true
			}

			if !ticketWasMissed {
				errStr := fmt.Sprintf("SSRtx spent missed sstx %v, "+
					"but that missed sstx could not be found!",
					hash)
				return errors.New(errStr)
			}
		}
	}

	// PART 3: Add newly maturing tickets
	// This is the only chunk we need to do for blocks appearing before
	// stake validation height.

	// Calculate block number for where new tickets are maturing from and retrieve
	// this block from db.

	// Get the block that is maturing.
	matureNode, err := b.getNodeAtHeightFromTopNode(node, tM)
	if err != nil {
		return err
	}

	matureBlock, errBlock := b.getBlockFromHash(matureNode.hash)
	if errBlock != nil {
		return errBlock
	}

	// Maturing tickets are from the maturingBlock; fill out the ticket patch data
	// and then push them to the tixStore.
	for _, stx := range matureBlock.STransactions() {
		if is, _ := stake.IsSStx(stx); is {
			// Calculate the prefix for pre-sort.
			sstxHash := *stx.Sha()
			prefix := uint8(sstxHash[0])

			// Fill out the ticket data.
			td := stake.NewTicketData(sstxHash,
				prefix,
				chainhash.Hash{},
				height,
				false, // not missed
				false) // not expired

			tpd := NewTicketPatchData(td,
				TiAvailable,
				nil)
			tixStore[*stx.Sha()] = tpd
		}
	}

	return nil
}