Golang wire.MsgTx类代码示例

// GetDoubleSpends takes a transaction and compares it with
// all transactions in the db.  It returns a slice of all txids in the db
// which are double spent by the received tx.
func CheckDoubleSpends(
	argTx *wire.MsgTx, txs []*wire.MsgTx) ([]*wire.ShaHash, error) {

	var dubs []*wire.ShaHash // slice of all double-spent txs
	argTxid := argTx.TxSha()

	for _, compTx := range txs {
		compTxid := compTx.TxSha()
		// check if entire tx is dup
		if argTxid.IsEqual(&compTxid) {
			return nil, fmt.Errorf("tx %s is dup", argTxid.String())
		}
		// not dup, iterate through inputs of argTx
		for _, argIn := range argTx.TxIn {
			// iterate through inputs of compTx
			for _, compIn := range compTx.TxIn {
				if OutPointsEqual(
					argIn.PreviousOutPoint, compIn.PreviousOutPoint) {
					// found double spend
					dubs = append(dubs, &compTxid)
					break // back to argIn loop
				}
			}
		}
	}
	return dubs, nil
}

// CalcPriority returns a transaction priority given a transaction and the sum
// of each of its input values multiplied by their age (# of confirmations).
// Thus, the final formula for the priority is:
// sum(inputValue * inputAge) / adjustedTxSize
func CalcPriority(tx *wire.MsgTx, utxoView *blockchain.UtxoViewpoint, nextBlockHeight int32) float64 {
	// In order to encourage spending multiple old unspent transaction
	// outputs thereby reducing the total set, don't count the constant
	// overhead for each input as well as enough bytes of the signature
	// script to cover a pay-to-script-hash redemption with a compressed
	// pubkey.  This makes additional inputs free by boosting the priority
	// of the transaction accordingly.  No more incentive is given to avoid
	// encouraging gaming future transactions through the use of junk
	// outputs.  This is the same logic used in the reference
	// implementation.
	//
	// The constant overhead for a txin is 41 bytes since the previous
	// outpoint is 36 bytes + 4 bytes for the sequence + 1 byte the
	// signature script length.
	//
	// A compressed pubkey pay-to-script-hash redemption with a maximum len
	// signature is of the form:
	// [OP_DATA_73 <73-byte sig> + OP_DATA_35 + {OP_DATA_33
	// <33 byte compresed pubkey> + OP_CHECKSIG}]
	//
	// Thus 1 + 73 + 1 + 1 + 33 + 1 = 110
	overhead := 0
	for _, txIn := range tx.TxIn {
		// Max inputs + size can't possibly overflow here.
		overhead += 41 + minInt(110, len(txIn.SignatureScript))
	}

	serializedTxSize := tx.SerializeSize()
	if overhead >= serializedTxSize {
		return 0.0
	}

	inputValueAge := calcInputValueAge(tx, utxoView, nextBlockHeight)
	return inputValueAge / float64(serializedTxSize-overhead)
}

// dbFetchTx looks up the passed transaction hash in the transaction index and
// loads it from the database.
func dbFetchTx(dbTx database.Tx, hash *chainhash.Hash) (*wire.MsgTx, error) {
	// Look up the location of the transaction.
	blockRegion, err := dbFetchTxIndexEntry(dbTx, hash)
	if err != nil {
		return nil, err
	}
	if blockRegion == nil {
		return nil, fmt.Errorf("transaction %v not found", hash)
	}

	// Load the raw transaction bytes from the database.
	txBytes, err := dbTx.FetchBlockRegion(blockRegion)
	if err != nil {
		return nil, err
	}

	// Deserialize the transaction.
	var msgTx wire.MsgTx
	err = msgTx.Deserialize(bytes.NewReader(txBytes))
	if err != nil {
		return nil, err
	}

	return &msgTx, nil
}

// AddSigHashes computes, then adds the partial sighashes for the passed
// transaction.
func (h *HashCache) AddSigHashes(tx *wire.MsgTx) {
	h.Lock()
	defer h.Unlock()

	sigHashes := NewTxSigHashes(tx)

	txid := tx.TxHash()
	h.sigHashes[txid] = sigHashes

	return
}

// TestCalcSignatureHash runs the Bitcoin Core signature hash calculation tests
// in sighash.json.
// https://github.com/bitcoin/bitcoin/blob/master/src/test/data/sighash.json
func TestCalcSignatureHash(t *testing.T) {
	file, err := ioutil.ReadFile("data/sighash.json")
	if err != nil {
		t.Errorf("TestCalcSignatureHash: %v\n", err)
		return
	}

	var tests [][]interface{}
	err = json.Unmarshal(file, &tests)
	if err != nil {
		t.Errorf("TestCalcSignatureHash couldn't Unmarshal: %v\n",
			err)
		return
	}

	for i, test := range tests {
		if i == 0 {
			// Skip first line -- contains comments only.
			continue
		}
		if len(test) != 5 {
			t.Fatalf("TestCalcSignatureHash: Test #%d has "+
				"wrong length.", i)
		}
		var tx wire.MsgTx
		rawTx, _ := hex.DecodeString(test[0].(string))
		err := tx.Deserialize(bytes.NewReader(rawTx))
		if err != nil {
			t.Errorf("TestCalcSignatureHash failed test #%d: "+
				"Failed to parse transaction: %v", i, err)
			continue
		}

		subScript, _ := hex.DecodeString(test[1].(string))
		parsedScript, err := parseScript(subScript)
		if err != nil {
			t.Errorf("TestCalcSignatureHash failed test #%d: "+
				"Failed to parse sub-script: %v", i, err)
			continue
		}

		hashType := SigHashType(testVecF64ToUint32(test[3].(float64)))
		hash := calcSignatureHash(parsedScript, hashType, &tx,
			int(test[2].(float64)))

		expectedHash, _ := chainhash.NewHashFromStr(test[4].(string))
		if !bytes.Equal(hash, expectedHash[:]) {
			t.Errorf("TestCalcSignatureHash failed test #%d: "+
				"Signature hash mismatch.", i)
		}
	}
}

func spendOutput(txHash *wire.ShaHash, index uint32, outputValues ...int64) *wire.MsgTx {
	tx := wire.MsgTx{
		TxIn: []*wire.TxIn{
			&wire.TxIn{
				PreviousOutPoint: wire.OutPoint{Hash: *txHash, Index: index},
			},
		},
	}
	for _, val := range outputValues {
		tx.TxOut = append(tx.TxOut, &wire.TxOut{Value: val})
	}
	return &tx
}

func newCoinBase(outputValues ...int64) *wire.MsgTx {
	tx := wire.MsgTx{
		TxIn: []*wire.TxIn{
			&wire.TxIn{
				PreviousOutPoint: wire.OutPoint{Index: ^uint32(0)},
			},
		},
	}
	for _, val := range outputValues {
		tx.TxOut = append(tx.TxOut, &wire.TxOut{Value: val})
	}
	return &tx
}

// receiverHtlcSpendRedeem constructs a valid witness allowing the receiver of
// an HTLC to redeem the conditional payment in the event that their commitment
// transaction is broadcast. Since this is a pay out to the receiving party as
// an output on their commitment transaction, a relative time delay is required
// before the output can be spent.
func receiverHtlcSpendRedeem(commitScript []byte, outputAmt btcutil.Amount,
	reciverKey *btcec.PrivateKey, sweepTx *wire.MsgTx,
	paymentPreimage []byte, relativeTimeout uint32) (wire.TxWitness, error) {

	// In order to properly spend the transaction, we need to set the
	// sequence number. We do this by convering the relative block delay
	// into a sequence number value able to be interpeted by
	// OP_CHECKSEQUENCEVERIFY.
	sweepTx.TxIn[0].Sequence = lockTimeToSequence(false, relativeTimeout)

	// Additionally, OP_CSV requires that the version of the transaction
	// spending a pkscript with OP_CSV within it *must* be >= 2.
	sweepTx.Version = 2

	hashCache := txscript.NewTxSigHashes(sweepTx)
	sweepSig, err := txscript.RawTxInWitnessSignature(
		sweepTx, hashCache, 0, int64(outputAmt), commitScript,
		txscript.SigHashAll, reciverKey)
	if err != nil {
		return nil, err
	}

	// Place a one as the first item in the evaluated witness stack to
	// force script execution to the HTLC redemption clause.
	witnessStack := wire.TxWitness(make([][]byte, 4))
	witnessStack[0] = sweepSig
	witnessStack[1] = paymentPreimage
	witnessStack[2] = []byte{1}
	witnessStack[3] = commitScript

	return witnessStack, nil
}

// receiverHtlcSpendTimeout constructs a valid witness allowing the sender of
// an HTLC to recover the pending funds after an absolute timeout in the
// scenario that the receiver of the HTLC broadcasts their version of the
// commitment transaction.
func receiverHtlcSpendTimeout(commitScript []byte, outputAmt btcutil.Amount,
	senderKey *btcec.PrivateKey, sweepTx *wire.MsgTx,
	absoluteTimeout uint32) (wire.TxWitness, error) {

	// The HTLC output has an absolute time period before we are permitted
	// to recover the pending funds. Therefore we need to set the locktime
	// on this sweeping transaction in order to pass Script verification.
	sweepTx.LockTime = absoluteTimeout

	hashCache := txscript.NewTxSigHashes(sweepTx)
	sweepSig, err := txscript.RawTxInWitnessSignature(
		sweepTx, hashCache, 0, int64(outputAmt), commitScript,
		txscript.SigHashAll, senderKey)
	if err != nil {
		return nil, err
	}

	witnessStack := wire.TxWitness(make([][]byte, 4))
	witnessStack[0] = sweepSig
	witnessStack[1] = []byte{0}
	witnessStack[2] = []byte{0}
	witnessStack[3] = commitScript

	return witnessStack, nil
}

func equalTxs(t *testing.T, got, exp *wire.MsgTx) {
	var bufGot, bufExp bytes.Buffer
	err := got.Serialize(&bufGot)
	if err != nil {
		t.Fatal(err)
	}
	err = exp.Serialize(&bufExp)
	if err != nil {
		t.Fatal(err)
	}
	if !bytes.Equal(bufGot.Bytes(), bufExp.Bytes()) {
		t.Errorf("Found unexpected wire.MsgTx:")
		t.Errorf("Got: %v", got)
		t.Errorf("Expected: %v", exp)
	}
}

// BUGS:
// - The transaction is not inspected to be relevant before publishing using
//   sendrawtransaction, so connection errors to btcd could result in the tx
//   never being added to the wallet database.
// - Once the above bug is fixed, wallet will require a way to purge invalid
//   transactions from the database when they are rejected by the network, other
//   than double spending them.
func (s *walletServer) PublishTransaction(ctx context.Context, req *pb.PublishTransactionRequest) (
	*pb.PublishTransactionResponse, error) {

	var msgTx wire.MsgTx
	err := msgTx.Deserialize(bytes.NewReader(req.SignedTransaction))
	if err != nil {
		return nil, grpc.Errorf(codes.InvalidArgument,
			"Bytes do not represent a valid raw transaction: %v", err)
	}

	err = s.wallet.PublishTransaction(&msgTx)
	if err != nil {
		return nil, translateError(err)
	}

	return &pb.PublishTransactionResponse{}, nil
}

// TxToString prints out some info about a transaction. for testing / debugging
func TxToString(tx *wire.MsgTx) string {
	str := fmt.Sprintf("size %d vsize %d wsize %d locktime %d txid %s\n",
		tx.SerializeSize(), blockchain.GetTxVirtualSize(btcutil.NewTx(tx)),
		tx.SerializeSize(), tx.LockTime, tx.TxSha().String())
	for i, in := range tx.TxIn {
		str += fmt.Sprintf("Input %d spends %s\n", i, in.PreviousOutPoint.String())
		str += fmt.Sprintf("\tSigScript: %x\n", in.SignatureScript)
		for j, wit := range in.Witness {
			str += fmt.Sprintf("\twitness %d: %x\n", j, wit)
		}
	}
	for i, out := range tx.TxOut {
		if out != nil {
			str += fmt.Sprintf("output %d script: %x amt: %d\n",
				i, out.PkScript, out.Value)
		} else {
			str += fmt.Sprintf("output %d nil (WARNING)\n", i)
		}
	}
	return str
}

func (s *SPVCon) NewOutgoingTx(tx *wire.MsgTx) error {
	txid := tx.TxSha()
	// assign height of zero for txs we create
	err := s.TS.AddTxid(&txid, 0)
	if err != nil {
		return err
	}
	_, err = s.TS.Ingest(tx, 0) // our own tx; don't keep track of false positives
	if err != nil {
		return err
	}
	// make an inv message instead of a tx message to be polite
	iv1 := wire.NewInvVect(wire.InvTypeWitnessTx, &txid)
	invMsg := wire.NewMsgInv()
	err = invMsg.AddInvVect(iv1)
	if err != nil {
		return err
	}
	s.outMsgQueue <- invMsg
	return nil
}

// htlcSpendTimeout constructs a valid witness allowing the sender of an HTLC
// to recover the pending funds after an absolute, then relative locktime
// period.
func senderHtlcSpendTimeout(commitScript []byte, outputAmt btcutil.Amount,
	senderKey *btcec.PrivateKey, sweepTx *wire.MsgTx,
	absoluteTimeout, relativeTimeout uint32) (wire.TxWitness, error) {

	// Since the HTLC output has an absolute timeout before we're permitted
	// to sweep the output, we need to set the locktime of this sweepign
	// transaction to that aboslute value in order to pass Script
	// verification.
	sweepTx.LockTime = absoluteTimeout

	// Additionally, we're required to wait a relative period of time
	// before we can sweep the output in order to allow the other party to
	// contest our claim of validity to this version of the commitment
	// transaction.
	sweepTx.TxIn[0].Sequence = lockTimeToSequence(false, relativeTimeout)

	// Finally, OP_CSV requires that the version of the transaction
	// spending a pkscript with OP_CSV within it *must* be >= 2.
	sweepTx.Version = 2

	hashCache := txscript.NewTxSigHashes(sweepTx)
	sweepSig, err := txscript.RawTxInWitnessSignature(
		sweepTx, hashCache, 0, int64(outputAmt), commitScript,
		txscript.SigHashAll, senderKey)
	if err != nil {
		return nil, err
	}

	// We place a zero as the first item of the evaluated witness stack in
	// order to force Script execution to the HTLC timeout clause.
	witnessStack := wire.TxWitness(make([][]byte, 3))
	witnessStack[0] = sweepSig
	witnessStack[1] = []byte{0}
	witnessStack[2] = commitScript

	return witnessStack, nil
}

// EstFee gives a fee estimate based on a tx and a sat/Byte target.
// The TX should have all outputs, including the change address already
// populated (with potentially 0 amount.  Also it should have all inputs
// populated, but inputs don't need to have sigscripts or witnesses
// (it'll guess the sizes of sigs/wits that arent' filled in).
func EstFee(otx *wire.MsgTx, spB int64) int64 {
	mtsig := make([]byte, 72)
	mtpub := make([]byte, 33)

	tx := otx.Copy()

	// iterate through txins, replacing subscript sigscripts with noise
	// sigs or witnesses
	for _, txin := range tx.TxIn {
		// check wpkh
		if len(txin.SignatureScript) == 22 &&
			txin.SignatureScript[0] == 0x00 && txin.SignatureScript[1] == 0x14 {
			txin.SignatureScript = nil
			txin.Witness = make([][]byte, 2)
			txin.Witness[0] = mtsig
			txin.Witness[1] = mtpub
		} else if len(txin.SignatureScript) == 34 &&
			txin.SignatureScript[0] == 0x00 && txin.SignatureScript[1] == 0x20 {
			// p2wsh -- sig lenght is a total guess!
			txin.SignatureScript = nil
			txin.Witness = make([][]byte, 3)
			// 3 sigs? totally guessing here
			txin.Witness[0] = mtsig
			txin.Witness[1] = mtsig
			txin.Witness[2] = mtsig
		} else {
			// assume everything else is p2pkh.  Even though it's not
			txin.Witness = nil
			txin.SignatureScript = make([]byte, 105) // len of p2pkh sigscript
		}
	}
	fmt.Printf(TxToString(tx))
	size := int64(blockchain.GetTxVirtualSize(btcutil.NewTx(tx)))
	fmt.Printf("%d spB, est vsize %d, fee %d\n", spB, size, size*spB)
	return size * spB
}