lnd.xprv/uspv/txstore.go
Tadge Dryja fbd17846d4 split adrs up into two slices?
here is code to keep track of two sets of addresses -- the
regular ones and the witness ones.  But maybe those should be
merged becuase it's easy for other wallets to switch between them
and send to the same 20 byte pubkey hash but wintessified.
So maybe I'll change this stuff...
2016-02-19 00:32:22 -08:00

341 lines
8.9 KiB
Go

package uspv
import (
"bytes"
"encoding/binary"
"fmt"
"log"
"sync"
"github.com/btcsuite/btcd/chaincfg"
"github.com/boltdb/bolt"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
"github.com/btcsuite/btcutil/bloom"
"github.com/btcsuite/btcutil/hdkeychain"
)
type TxStore struct {
OKTxids map[wire.ShaHash]int32 // known good txids and their heights
OKMutex sync.Mutex
Adrs []MyAdr // endeavouring to acquire capital
WitAdrs []MyAdr // separate segwit address slice
StateDB *bolt.DB // place to write all this down
// Params live here, not SCon
Param *chaincfg.Params // network parameters (testnet3, testnetL)
// From here, comes everything. It's a secret to everybody.
rootPrivKey *hdkeychain.ExtendedKey
}
type Utxo struct { // cash money.
Op wire.OutPoint // where
// all the info needed to spend
AtHeight int32 // block height where this tx was confirmed, 0 for unconf
KeyIdx uint32 // index for private key needed to sign / spend
Value int64 // higher is better
// IsCoinbase bool // can't spend for a while
IsWit bool // true if p2wpkh output
}
// Stxo is a utxo that has moved on.
type Stxo struct {
Utxo // when it used to be a utxo
SpendHeight int32 // height at which it met its demise
SpendTxid wire.ShaHash // the tx that consumed it
}
type MyAdr struct { // an address I have the private key for
PkhAdr btcutil.Address
KeyIdx uint32 // index for private key needed to sign / spend
// ^^ this is kindof redundant because it'll just be their position
// inside the Adrs slice, right? leave for now
}
func NewTxStore(rootkey *hdkeychain.ExtendedKey, p *chaincfg.Params) TxStore {
var txs TxStore
txs.rootPrivKey = rootkey
txs.Param = p
txs.OKTxids = make(map[wire.ShaHash]int32)
return txs
}
// add txid of interest
func (t *TxStore) AddTxid(txid *wire.ShaHash, height int32) error {
if txid == nil {
return fmt.Errorf("tried to add nil txid")
}
log.Printf("added %s to OKTxids at height %d\n", txid.String(), height)
t.OKMutex.Lock()
t.OKTxids[*txid] = height
t.OKMutex.Unlock()
return nil
}
// ... or I'm gonna fade away
func (t *TxStore) GimmeFilter() (*bloom.Filter, error) {
if len(t.Adrs) == 0 && len(t.WitAdrs) == 9 {
return nil, fmt.Errorf("no address to filter for")
}
// get all utxos to add outpoints to filter
allUtxos, err := t.GetAllUtxos()
if err != nil {
return nil, err
}
elem := uint32(len(t.Adrs) + len(t.WitAdrs) + len(allUtxos))
f := bloom.NewFilter(elem, 0, 0.000001, wire.BloomUpdateAll)
// note there could be false positives since we're just looking
// for the 20 byte PKH without the opcodes.
for _, a := range t.Adrs { // add 20-byte pubkeyhash
f.Add(a.PkhAdr.ScriptAddress())
}
for _, a := range t.WitAdrs { // add witness 20-byte pubkeyhash
f.Add(a.PkhAdr.ScriptAddress())
}
for _, u := range allUtxos {
f.AddOutPoint(&u.Op)
}
return f, nil
}
// 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
}
// TxToString prints out some info about a transaction. for testing / debugging
func TxToString(tx *wire.MsgTx) string {
str := fmt.Sprintf("\t size %d vsize %d wsize %d Tx %s\n",
tx.SerializeSize(), tx.VirtualSize(), tx.SerializeSizeWitness(),
tx.TxSha().String())
for i, in := range tx.TxIn {
str += fmt.Sprintf("Input %d: %s\n", i, in.PreviousOutPoint.String())
str += fmt.Sprintf("SigScript for input %d: %x\n", i, in.SignatureScript)
for j, wit := range in.Witness {
str += fmt.Sprintf("witness %d: %x\t", j, wit)
}
str += fmt.Sprintf("\n")
}
for i, out := range tx.TxOut {
if out != nil {
str += fmt.Sprintf("\toutput %d script: %x amt: %d\n",
i, out.PkScript, out.Value)
} else {
str += fmt.Sprintf("output %d nil (WARNING)\n", i)
}
}
return str
}
// need this because before I was comparing pointers maybe?
// so they were the same outpoint but stored in 2 places so false negative?
func OutPointsEqual(a, b wire.OutPoint) bool {
if !a.Hash.IsEqual(&b.Hash) {
return false
}
return a.Index == b.Index
}
/*----- serialization for tx outputs ------- */
// outPointToBytes turns an outpoint into 36 bytes.
func outPointToBytes(op *wire.OutPoint) ([]byte, error) {
var buf bytes.Buffer
_, err := buf.Write(op.Hash.Bytes())
if err != nil {
return nil, err
}
// write 4 byte outpoint index within the tx to spend
err = binary.Write(&buf, binary.BigEndian, op.Index)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// ToBytes turns a Utxo into some bytes.
// note that the txid is the first 36 bytes and in our use cases will be stripped
// off, but is left here for other applications
func (u *Utxo) ToBytes() ([]byte, error) {
var buf bytes.Buffer
// write 32 byte txid of the utxo
_, err := buf.Write(u.Op.Hash.Bytes())
if err != nil {
return nil, err
}
// write 4 byte outpoint index within the tx to spend
err = binary.Write(&buf, binary.BigEndian, u.Op.Index)
if err != nil {
return nil, err
}
// write 4 byte height of utxo
err = binary.Write(&buf, binary.BigEndian, u.AtHeight)
if err != nil {
return nil, err
}
// write 4 byte key index of utxo
err = binary.Write(&buf, binary.BigEndian, u.KeyIdx)
if err != nil {
return nil, err
}
// write 8 byte amount of money at the utxo
err = binary.Write(&buf, binary.BigEndian, u.Value)
if err != nil {
return nil, err
}
// last byte indicates tx witness flags ( tx[5] from serialized tx)
// write a 1 at the end for p2wpkh (same as flags byte)
witByte := byte(0x00)
if u.IsWit {
witByte = 0x01
}
err = buf.WriteByte(witByte)
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// UtxoFromBytes turns bytes into a Utxo. Note it wants the txid and outindex
// in the first 36 bytes, which isn't stored that way in the boldDB,
// but can be easily appended.
func UtxoFromBytes(b []byte) (Utxo, error) {
var u Utxo
if b == nil {
return u, fmt.Errorf("nil input slice")
}
buf := bytes.NewBuffer(b)
if buf.Len() < 53 { // utxos are 53 bytes
return u, fmt.Errorf("Got %d bytes for utxo, expect 53", buf.Len())
}
// read 32 byte txid
err := u.Op.Hash.SetBytes(buf.Next(32))
if err != nil {
return u, err
}
// read 4 byte outpoint index within the tx to spend
err = binary.Read(buf, binary.BigEndian, &u.Op.Index)
if err != nil {
return u, err
}
// read 4 byte height of utxo
err = binary.Read(buf, binary.BigEndian, &u.AtHeight)
if err != nil {
return u, err
}
// read 4 byte key index of utxo
err = binary.Read(buf, binary.BigEndian, &u.KeyIdx)
if err != nil {
return u, err
}
// read 8 byte amount of money at the utxo
err = binary.Read(buf, binary.BigEndian, &u.Value)
if err != nil {
return u, err
}
// read 1 byte witness flags
witByte, err := buf.ReadByte()
if err != nil {
return u, err
}
if witByte != 0x00 {
u.IsWit = true
}
return u, nil
}
// ToBytes turns an Stxo into some bytes.
// prevUtxo serialization, then spendheight [4], spendtxid [32]
func (s *Stxo) ToBytes() ([]byte, error) {
var buf bytes.Buffer
// first serialize the utxo part
uBytes, err := s.Utxo.ToBytes()
if err != nil {
return nil, err
}
// write that into the buffer first
_, err = buf.Write(uBytes)
if err != nil {
return nil, err
}
// write 4 byte height where the txo was spent
err = binary.Write(&buf, binary.BigEndian, s.SpendHeight)
if err != nil {
return nil, err
}
// write 32 byte txid of the spending transaction
_, err = buf.Write(s.SpendTxid.Bytes())
if err != nil {
return nil, err
}
return buf.Bytes(), nil
}
// StxoFromBytes turns bytes into a Stxo.
// first take the first 53 bytes as a utxo, then the next 36 for how it's spent.
func StxoFromBytes(b []byte) (Stxo, error) {
var s Stxo
if len(b) < 89 {
return s, fmt.Errorf("Got %d bytes for stxo, expect 89", len(b))
}
u, err := UtxoFromBytes(b[:53])
if err != nil {
return s, err
}
s.Utxo = u // assign the utxo
buf := bytes.NewBuffer(b[53:]) // make buffer for spend data
// read 4 byte spend height
err = binary.Read(buf, binary.BigEndian, &s.SpendHeight)
if err != nil {
return s, err
}
// read 32 byte txid
err = s.SpendTxid.SetBytes(buf.Next(32))
if err != nil {
return s, err
}
return s, nil
}