// fetchTxDataByLoc returns several pieces of data regarding the given tx
// located by the block/offset/size location
func (db *LevelDb) fetchTxDataByLoc(blkHeight int32, txOff int, txLen int, txspent []byte) (rtx *wire.MsgTx, rblksha *wire.ShaHash, rheight int32, rtxspent []byte, err error) {
var blksha *wire.ShaHash
var blkbuf []byte
blksha, blkbuf, err = db.getBlkByHeight(blkHeight)
if err != nil {
if err == leveldb.ErrNotFound {
err = database.ErrTxShaMissing
}
return
}
//log.Trace("transaction %v is at block %v %v txoff %v, txlen %v\n",
// txsha, blksha, blkHeight, txOff, txLen)
if len(blkbuf) < txOff+txLen {
err = database.ErrTxShaMissing
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)
return
}
return &tx, blksha, blkHeight, txspent, nil
}
// 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 signature script length.
{multiTx, multiTxEncoded, 41, io.ErrShortWrite, io.EOF},
// Force error in transaction input signature script.
{multiTx, multiTxEncoded, 42, io.ErrShortWrite, io.EOF},
// Force error in transaction input sequence.
{multiTx, multiTxEncoded, 49, io.ErrShortWrite, io.EOF},
// Force error in number of transaction outputs.
{multiTx, multiTxEncoded, 53, io.ErrShortWrite, io.EOF},
// Force error in transaction output value.
{multiTx, multiTxEncoded, 54, io.ErrShortWrite, io.EOF},
// Force error in transaction output pk script length.
{multiTx, multiTxEncoded, 62, io.ErrShortWrite, io.EOF},
// Force error in transaction output pk script.
{multiTx, multiTxEncoded, 63, io.ErrShortWrite, io.EOF},
// Force error in transaction output lock time.
{multiTx, multiTxEncoded, 206, 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
}
}
}
// NewTxFromReader returns a new instance of a bitcoin 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{
msgTx: &msgTx,
txIndex: TxIndexUnknown,
}
return &t, nil
}
// TestTxOverflowErrors performs tests to ensure deserializing transactions
// which are intentionally crafted to use large values for the variable number
// of inputs and outputs are handled properly. This could otherwise potentially
// be used as an attack vector.
func TestTxOverflowErrors(t *testing.T) {
// Use protocol version 70001 and transaction version 1 specifically
// here instead of the latest values because the test data is using
// bytes encoded with those versions.
pver := uint32(70001)
txVer := uint32(1)
tests := []struct {
buf []byte // Wire encoding
pver uint32 // Protocol version for wire encoding
version uint32 // Transaction version
err error // Expected error
}{
// Transaction that claims to have ~uint64(0) inputs.
{
[]byte{
0x00, 0x00, 0x00, 0x01, // Version
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, // Varint for number of input transactions
}, pver, txVer, &wire.MessageError{},
},
// Transaction that claims to have ~uint64(0) outputs.
{
[]byte{
0x00, 0x00, 0x00, 0x01, // 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
// claims to have ~uint64(0) length.
{
[]byte{
0x00, 0x00, 0x00, 0x01, // 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
0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
0xff, // Varint for length of signature script
}, pver, txVer, &wire.MessageError{},
},
// Transaction that has an output with a public key script
// that claims to have ~uint64(0) length.
{
[]byte{
0x00, 0x00, 0x00, 0x01, // 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, // 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))
continue
}
// 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
}
}
}
// TestTxSerialize tests MsgTx serialize and deserialize.
func TestTxSerialize(t *testing.T) {
noTx := wire.NewMsgTx()
noTx.Version = 1
noTxEncoded := []byte{
0x01, 0x00, 0x00, 0x00, // Version
0x00, // Varint for number of input transactions
0x00, // Varint for number of output transactions
0x00, 0x00, 0x00, 0x00, // Lock time
}
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.
{
multiTx,
multiTx,
multiTxEncoded,
multiTxPkScriptLocs,
},
}
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
}
// 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))
}
}
}
}