Golang MsgTx.Deserialize方法代碼示例

// Receive waits for the response promised by the future and returns a
// transaction given its hash.
func (r FutureGetRawTransactionResult) Receive() (*dcrutil.Tx, error) {
	res, err := receiveFuture(r)
	if err != nil {
		return nil, err
	}

	// Unmarshal result as a string.
	var txHex string
	err = json.Unmarshal(res, &txHex)
	if err != nil {
		return nil, err
	}

	// Decode the serialized transaction hex to raw bytes.
	serializedTx, err := hex.DecodeString(txHex)
	if err != nil {
		return nil, err
	}

	// Deserialize the transaction and return it.
	var msgTx wire.MsgTx
	if err := msgTx.Deserialize(bytes.NewReader(serializedTx)); err != nil {
		return nil, err
	}
	return dcrutil.NewTx(&msgTx), nil
}

// fetchTxDataByLoc returns several pieces of data regarding the given tx
// located by the block/offset/size location
func (db *LevelDb) fetchTxDataByLoc(blkHeight int64, txOff int, txLen int, txspent []byte) (rtx *wire.MsgTx, rblksha *chainhash.Hash, rheight int64, rtxspent []byte, err error) {
	var blksha *chainhash.Hash
	var blkbuf []byte

	blksha, blkbuf, err = db.getBlkByHeight(blkHeight)
	if err != nil {
		if err == leveldb.ErrNotFound {
			err = database.ErrTxShaMissing
		}
		return
	}

	if len(blkbuf) < txOff+txLen {
		log.Warnf("block buffer overrun while looking for tx: "+
			"block %v %v txoff %v txlen %v", blkHeight, blksha, txOff, txLen)
		err = database.ErrDbInconsistency
		return
	}
	rbuf := bytes.NewReader(blkbuf[txOff : txOff+txLen])

	var tx wire.MsgTx
	err = tx.Deserialize(rbuf)
	if err != nil {
		log.Warnf("unable to decode tx block %v %v txoff %v txlen %v",
			blkHeight, blksha, txOff, txLen)
		err = database.ErrDbInconsistency
		return
	}

	return &tx, blksha, blkHeight, txspent, nil
}

// 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 in the txindex", 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
}

// deserializeSStxRecord deserializes the passed serialized tx record information.
func deserializeSStxRecord(serializedSStxRecord []byte) (*sstxRecord, error) {
	record := new(sstxRecord)

	curPos := 0

	// Read MsgTx size (as a uint64).
	msgTxLen := int(byteOrder.Uint64(
		serializedSStxRecord[curPos : curPos+int64Size]))
	curPos += int64Size

	// Pretend to read the pkScrLoc for the 0th output pkScript.
	curPos += int32Size

	// Read the intended voteBits and extended voteBits length (uint8).
	record.voteBitsSet = false
	voteBitsLen := uint8(serializedSStxRecord[curPos])
	if voteBitsLen != 0 {
		record.voteBitsSet = true
	}
	curPos += int8Size

	// Read the assumed 2 byte VoteBits as well as the extended
	// votebits (75 bytes max).
	record.voteBits = byteOrder.Uint16(
		serializedSStxRecord[curPos : curPos+int16Size])
	curPos += int16Size
	record.voteBitsExt = make([]byte, int(voteBitsLen)-int16Size)
	copy(record.voteBitsExt[:],
		serializedSStxRecord[curPos:curPos+int(voteBitsLen)-int16Size])
	curPos += stake.MaxSingleBytePushLength - int16Size

	// Prepare a buffer for the msgTx.
	buf := bytes.NewBuffer(serializedSStxRecord[curPos : curPos+msgTxLen])
	curPos += msgTxLen

	// Deserialize transaction.
	msgTx := new(wire.MsgTx)
	err := msgTx.Deserialize(buf)
	if err != nil {
		if err == io.EOF {
			err = io.ErrUnexpectedEOF
		}
		return nil, err
	}

	// Create and save the dcrutil.Tx of the read MsgTx and set its index.
	tx := dcrutil.NewTx((*wire.MsgTx)(msgTx))
	tx.SetIndex(dcrutil.TxIndexUnknown)
	tx.SetTree(dcrutil.TxTreeStake)
	record.tx = tx

	// Read received unix time (int64).
	received := int64(byteOrder.Uint64(
		serializedSStxRecord[curPos : curPos+int64Size]))
	curPos += int64Size
	record.ts = time.Unix(received, 0)

	return record, nil
}

// NewTxFromReader returns a new instance of a transaction given a
// Reader to deserialize the transaction.  See Tx.
func NewTxFromReader(r io.Reader) (*Tx, error) {
	// Deserialize the bytes into a MsgTx.
	var msgTx wire.MsgTx
	err := msgTx.Deserialize(r)
	if err != nil {
		return nil, err
	}

	t := Tx{
		hash:    msgTx.TxHash(),
		msgTx:   &msgTx,
		txTree:  wire.TxTreeUnknown,
		txIndex: TxIndexUnknown,
	}

	return &t, nil
}

// BUGS:
// - The transaction is not inspected to be relevant before publishing using
//   sendrawtransaction, so connection errors to dcrd 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)
	}

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

	return &pb.PublishTransactionResponse{TransactionHash: txHash[:]}, nil
}

// BUGS:
// - InputIndexes request field is ignored.
func (s *walletServer) SignTransaction(ctx context.Context, req *pb.SignTransactionRequest) (
	*pb.SignTransactionResponse, error) {

	defer zero.Bytes(req.Passphrase)

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

	lock := make(chan time.Time, 1)
	defer func() {
		lock <- time.Time{} // send matters, not the value
	}()
	err = s.wallet.Unlock(req.Passphrase, lock)
	if err != nil {
		return nil, translateError(err)
	}

	invalidSigs, err := s.wallet.SignTransaction(&tx, txscript.SigHashAll, nil, nil, nil)
	if err != nil {
		return nil, translateError(err)
	}

	invalidInputIndexes := make([]uint32, len(invalidSigs))
	for i, e := range invalidSigs {
		invalidInputIndexes[i] = e.InputIndex
	}

	var serializedTransaction bytes.Buffer
	serializedTransaction.Grow(tx.SerializeSize())
	err = tx.Serialize(&serializedTransaction)
	if err != nil {
		return nil, translateError(err)
	}

	resp := &pb.SignTransactionResponse{
		Transaction:          serializedTransaction.Bytes(),
		UnsignedInputIndexes: invalidInputIndexes,
	}
	return resp, nil
}

//.........這裏部分代碼省略.........
		{
			[]byte{
				0x01, 0x00, 0x00, 0x00, // Version
				0x00, // Varint for number of input transactions
				0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
				0xff, // Varint for number of output transactions
			}, pver, txVer, &wire.MessageError{},
		},

		// Transaction that has an input with a signature script that [2]
		// claims to have ~uint64(0) length.
		{
			[]byte{
				0x01, 0x00, 0x00, 0x00, // Version
				0x01, // Varint for number of input transactions
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Previous output hash
				0xff, 0xff, 0xff, 0xff, // Previous output index
				0x00,                   // Previous output tree
				0x00,                   // Varint for length of signature script
				0xff, 0xff, 0xff, 0xff, // Sequence
				0x02,                                           // Varint for number of output transactions
				0x00, 0xf2, 0x05, 0x2a, 0x01, 0x00, 0x00, 0x00, // Transaction amount
				0x43, // Varint for length of pk script
				0x41, // OP_DATA_65
				0x04, 0xd6, 0x4b, 0xdf, 0xd0, 0x9e, 0xb1, 0xc5,
				0xfe, 0x29, 0x5a, 0xbd, 0xeb, 0x1d, 0xca, 0x42,
				0x81, 0xbe, 0x98, 0x8e, 0x2d, 0xa0, 0xb6, 0xc1,
				0xc6, 0xa5, 0x9d, 0xc2, 0x26, 0xc2, 0x86, 0x24,
				0xe1, 0x81, 0x75, 0xe8, 0x51, 0xc9, 0x6b, 0x97,
				0x3d, 0x81, 0xb0, 0x1c, 0xc3, 0x1f, 0x04, 0x78,
				0x34, 0xbc, 0x06, 0xd6, 0xd6, 0xed, 0xf6, 0x20,
				0xd1, 0x84, 0x24, 0x1a, 0x6a, 0xed, 0x8b, 0x63,
				0xa6,                                           // 65-byte signature
				0xac,                                           // OP_CHECKSIG
				0x00, 0xe1, 0xf5, 0x05, 0x00, 0x00, 0x00, 0x00, // Transaction amount
				0x43, // Varint for length of pk script
				0x41, // OP_DATA_65
				0x04, 0xd6, 0x4b, 0xdf, 0xd0, 0x9e, 0xb1, 0xc5,
				0xfe, 0x29, 0x5a, 0xbd, 0xeb, 0x1d, 0xca, 0x42,
				0x81, 0xbe, 0x98, 0x8e, 0x2d, 0xa0, 0xb6, 0xc1,
				0xc6, 0xa5, 0x9d, 0xc2, 0x26, 0xc2, 0x86, 0x24,
				0xe1, 0x81, 0x75, 0xe8, 0x51, 0xc9, 0x6b, 0x97,
				0x3d, 0x81, 0xb0, 0x1c, 0xc3, 0x1f, 0x04, 0x78,
				0x34, 0xbc, 0x06, 0xd6, 0xd6, 0xed, 0xf6, 0x20,
				0xd1, 0x84, 0x24, 0x1a, 0x6a, 0xed, 0x8b, 0x63,
				0xa6,                   // 65-byte signature
				0xac,                   // OP_CHECKSIG
				0x00, 0x00, 0x00, 0x00, // Lock time
				0x00, 0x00, 0x00, 0x00, // Expiry
				0x01,                                                 // Varint for number of input signature
				0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, // Varint for sig script length (overflows)
			}, pver, txVer, &wire.MessageError{},
		},

		// Transaction that has an output with a public key script [3]
		// that claims to have ~uint64(0) length.
		{
			[]byte{
				0x01, 0x00, 0x00, 0x00, // Version
				0x01, // Varint for number of input transactions
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Previous output hash
				0xff, 0xff, 0xff, 0xff, // Prevous output index
				0x00,                   // Previous output tree
				0x00,                   // Varint for length of signature script
				0xff, 0xff, 0xff, 0xff, // Sequence
				0x01,                                           // Varint for number of output transactions
				0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, // Transaction amount
				0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
				0xff, // Varint for length of public key script
			}, pver, txVer, &wire.MessageError{},
		},
	}

	t.Logf("Running %d tests", len(tests))
	for i, test := range tests {
		// Decode from wire format.
		var msg wire.MsgTx
		r := bytes.NewReader(test.buf)
		err := msg.BtcDecode(r, test.pver)
		if reflect.TypeOf(err) != reflect.TypeOf(test.err) {
			t.Errorf("BtcDecode #%d wrong error got: %v, want: %v",
				i, err, reflect.TypeOf(test.err))
		}

		// Decode from wire format.
		r = bytes.NewReader(test.buf)
		err = msg.Deserialize(r)
		if reflect.TypeOf(err) != reflect.TypeOf(test.err) {
			t.Errorf("Deserialize #%d wrong error got: %v, want: %v",
				i, err, reflect.TypeOf(test.err))
			continue
		}
	}
}

// TestTxSerializeErrors performs negative tests against wire encode and decode
// of MsgTx to confirm error paths work correctly.
func TestTxSerializeErrors(t *testing.T) {
	tests := []struct {
		in       *wire.MsgTx // Value to encode
		buf      []byte      // Serialized data
		max      int         // Max size of fixed buffer to induce errors
		writeErr error       // Expected write error
		readErr  error       // Expected read error
	}{
		// Force error in version.
		{multiTx, multiTxEncoded, 0, io.ErrShortWrite, io.EOF},
		// Force error in number of transaction inputs.
		{multiTx, multiTxEncoded, 4, io.ErrShortWrite, io.EOF},
		// Force error in transaction input previous block hash.
		{multiTx, multiTxEncoded, 5, io.ErrShortWrite, io.EOF},
		// Force error in transaction input previous block output index.
		{multiTx, multiTxEncoded, 37, io.ErrShortWrite, io.EOF},
		// Force error in transaction input previous block output tree.
		{multiTx, multiTxEncoded, 41, io.ErrShortWrite, io.EOF},
		// Force error in transaction input sequence.
		{multiTx, multiTxEncoded, 42, io.ErrShortWrite, io.EOF},
		// Force error in number of transaction outputs.
		{multiTx, multiTxEncoded, 46, io.ErrShortWrite, io.EOF},
		// Force error in transaction output value.
		{multiTx, multiTxEncoded, 47, io.ErrShortWrite, io.EOF},
		// Force error in transaction output version.
		{multiTx, multiTxEncoded, 55, io.ErrShortWrite, io.EOF},
		// Force error in transaction output pk script length.
		{multiTx, multiTxEncoded, 57, io.ErrShortWrite, io.EOF},
		// Force error in transaction output pk script.
		{multiTx, multiTxEncoded, 58, io.ErrShortWrite, io.EOF},
		// Force error in transaction lock time.
		{multiTx, multiTxEncoded, 203, io.ErrShortWrite, io.EOF},
		// Force error in transaction expiry.
		{multiTx, multiTxEncoded, 207, io.ErrShortWrite, io.EOF},
		// Force error in transaction num sig varint.
		{multiTx, multiTxEncoded, 211, io.ErrShortWrite, io.EOF},
		// Force error in transaction sig 0 ValueIn.
		{multiTx, multiTxEncoded, 212, io.ErrShortWrite, io.EOF},
		// Force error in transaction sig 0 BlockHeight.
		{multiTx, multiTxEncoded, 220, io.ErrShortWrite, io.EOF},
		// Force error in transaction sig 0 BlockIndex.
		{multiTx, multiTxEncoded, 224, io.ErrShortWrite, io.EOF},
		// Force error in transaction sig 0 length.
		{multiTx, multiTxEncoded, 228, io.ErrShortWrite, io.EOF},
		// Force error in transaction sig 0 signature script.
		{multiTx, multiTxEncoded, 229, io.ErrShortWrite, io.EOF},
	}

	t.Logf("Running %d tests", len(tests))
	for i, test := range tests {
		// Serialize the transaction.
		w := newFixedWriter(test.max)
		err := test.in.Serialize(w)
		if err != test.writeErr {
			t.Errorf("Serialize #%d wrong error got: %v, want: %v",
				i, err, test.writeErr)
			continue
		}

		// Deserialize the transaction.
		var tx wire.MsgTx
		r := newFixedReader(test.max, test.buf)
		err = tx.Deserialize(r)
		if err != test.readErr {
			t.Errorf("Deserialize #%d wrong error got: %v, want: %v",
				i, err, test.readErr)
			continue
		}
	}
}

// TestTxSerializeWitnessValueSigning tests MsgTx serialize and deserialize.
func TestTxSerializeWitnessValueSigning(t *testing.T) {
	noTx := wire.NewMsgTx()
	noTx.Version = 262145
	noTxEncoded := []byte{
		0x01, 0x00, 0x04, 0x00, // Version
		0x00, // Varint for number of input signatures
	}

	tests := []struct {
		in           *wire.MsgTx // Message to encode
		out          *wire.MsgTx // Expected decoded message
		buf          []byte      // Serialized data
		pkScriptLocs []int       // Expected output script locations
	}{
		// No transactions.
		{
			noTx,
			noTx,
			noTxEncoded,
			nil,
		},

		// Multiple transactions.
		{
			multiTxWitnessValueSigning,
			multiTxWitnessValueSigning,
			multiTxWitnessValueSigningEncoded,
			nil,
		},
	}

	t.Logf("Running %d tests", len(tests))
	for i, test := range tests {
		// Serialize the transaction.
		var buf bytes.Buffer
		err := test.in.Serialize(&buf)
		if err != nil {
			t.Errorf("Serialize #%d error %v", i, err)
			continue
		}
		if !bytes.Equal(buf.Bytes(), test.buf) {
			t.Errorf("Serialize #%d\n got: %s want: %s", i,
				spew.Sdump(buf.Bytes()), spew.Sdump(test.buf))
			continue
		}

		// Test SerializeSize.
		sz := test.in.SerializeSize()
		actualSz := len(buf.Bytes())
		if sz != actualSz {
			t.Errorf("Wrong serialize size #%d\n got: %s want: %s", i,
				sz, actualSz)
		}

		// Deserialize the transaction.
		var tx wire.MsgTx
		rbuf := bytes.NewReader(test.buf)
		err = tx.Deserialize(rbuf)
		if err != nil {
			t.Errorf("Deserialize #%d error %v", i, err)
			continue
		}
		if !reflect.DeepEqual(&tx, test.out) {
			t.Errorf("Deserialize #%d\n got: %s want: %s", i,
				spew.Sdump(&tx), spew.Sdump(test.out))
			continue
		}

		// Ensure the public key script locations are accurate.
		pkScriptLocs := test.in.PkScriptLocs()
		if !reflect.DeepEqual(pkScriptLocs, test.pkScriptLocs) {
			t.Errorf("PkScriptLocs #%d\n got: %s want: %s", i,
				spew.Sdump(pkScriptLocs),
				spew.Sdump(test.pkScriptLocs))
			continue
		}
		for j, loc := range pkScriptLocs {
			wantPkScript := test.in.TxOut[j].PkScript
			gotPkScript := test.buf[loc : loc+len(wantPkScript)]
			if !bytes.Equal(gotPkScript, wantPkScript) {
				t.Errorf("PkScriptLocs #%d:%d\n unexpected "+
					"script got: %s want: %s", i, j,
					spew.Sdump(gotPkScript),
					spew.Sdump(wantPkScript))
			}
		}
	}
}

// loadTxStore returns a transaction store loaded from a file.
func loadTxStore(filename string) (blockchain.TxStore, error) {
	// The txstore file format is:
	// <num tx data entries> <tx length> <serialized tx> <blk height>
	// <num spent bits> <spent bits>
	//
	// All num and length fields are little-endian uint32s.  The spent bits
	// field is padded to a byte boundary.

	filename = filepath.Join("testdata/", filename)
	fi, err := os.Open(filename)
	if err != nil {
		return nil, err
	}

	// Choose read based on whether the file is compressed or not.
	var r io.Reader
	if strings.HasSuffix(filename, ".bz2") {
		r = bzip2.NewReader(fi)
	} else {
		r = fi
	}
	defer fi.Close()

	// Num of transaction store objects.
	var numItems uint32
	if err := binary.Read(r, binary.LittleEndian, &numItems); err != nil {
		return nil, err
	}

	txStore := make(blockchain.TxStore)
	var uintBuf uint32
	for height := uint32(0); height < numItems; height++ {
		txD := blockchain.TxData{}

		// Serialized transaction length.
		err = binary.Read(r, binary.LittleEndian, &uintBuf)
		if err != nil {
			return nil, err
		}
		serializedTxLen := uintBuf
		if serializedTxLen > wire.MaxBlockPayload {
			return nil, fmt.Errorf("Read serialized transaction "+
				"length of %d is larger max allowed %d",
				serializedTxLen, wire.MaxBlockPayload)
		}

		// Transaction.
		var msgTx wire.MsgTx
		err = msgTx.Deserialize(r)
		if err != nil {
			return nil, err
		}
		txD.Tx = dcrutil.NewTx(&msgTx)

		// Transaction hash.
		txHash := msgTx.TxSha()
		txD.Hash = &txHash

		// Block height the transaction came from.
		err = binary.Read(r, binary.LittleEndian, &uintBuf)
		if err != nil {
			return nil, err
		}
		txD.BlockHeight = int64(uintBuf)

		// Num spent bits.
		err = binary.Read(r, binary.LittleEndian, &uintBuf)
		if err != nil {
			return nil, err
		}
		numSpentBits := uintBuf
		numSpentBytes := numSpentBits / 8
		if numSpentBits%8 != 0 {
			numSpentBytes++
		}

		// Packed spent bytes.
		spentBytes := make([]byte, numSpentBytes)
		_, err = io.ReadFull(r, spentBytes)
		if err != nil {
			return nil, err
		}

		// Populate spent data based on spent bits.
		txD.Spent = make([]bool, numSpentBits)
		for byteNum, spentByte := range spentBytes {
			for bit := 0; bit < 8; bit++ {
				if uint32((byteNum*8)+bit) < numSpentBits {
					if spentByte&(1<<uint(bit)) != 0 {
						txD.Spent[(byteNum*8)+bit] = true
					}
				}
			}
		}

		txStore[*txD.Hash] = &txD
	}

	return txStore, nil
//.........這裏部分代碼省略.........