예제 #1
0
// AbsorbTx absorbs money into wallet from a tx
func (t *TxStore) AbsorbTx(tx *wire.MsgTx) error {
	if tx == nil {
		return fmt.Errorf("Tried to add nil tx")
	}
	var hits uint32
	var acq int64
	// check if any of the tx's outputs match my adrs
	for i, out := range tx.TxOut { // in each output of tx
		for _, a := range t.Adrs { // compare to each adr we have
			// more correct would be to check for full script
			// contains could have false positive? (p2sh/p2pkh same hash ..?)
			if bytes.Contains(out.PkScript, a.ScriptAddress()) { // hit
				hits++
				acq += out.Value
				var newu Utxo
				newu.KeyIdx = a.KeyIdx
				newu.Txo = *out

				var newop wire.OutPoint
				newop.Hash = tx.TxSha()
				newop.Index = uint32(i)
				newu.Op = newop

				t.Utxos = append(t.Utxos, newu)
				break
			}
		}
	}
	log.Printf("%d hits, acquired %d", hits, acq)
	t.Sum += acq
	return nil
}
예제 #2
0
파일: utxodb.go 프로젝트: conseweb/lnd
// Ingest puts a tx into the DB atomically.  This can result in a
// gain, a loss, or no result.  Gain or loss in satoshis is returned.
func (ts *TxStore) Ingest(tx *wire.MsgTx, height int32) (uint32, error) {
	var hits uint32
	var err error
	var spentOPs [][]byte
	var nUtxoBytes [][]byte

	// tx has been OK'd by SPV; check tx sanity
	utilTx := btcutil.NewTx(tx) // convert for validation
	// checks basic stuff like there are inputs and ouputs
	err = blockchain.CheckTransactionSanity(utilTx)
	if err != nil {
		return hits, err
	}
	// note that you can't check signatures; this is SPV.
	// 0 conf SPV means pretty much nothing.  Anyone can say anything.

	// before entering into db, serialize all inputs of the ingested tx
	for _, txin := range tx.TxIn {
		nOP, err := outPointToBytes(&txin.PreviousOutPoint)
		if err != nil {
			return hits, err
		}
		spentOPs = append(spentOPs, nOP)
	}
	// also generate PKscripts for all addresses (maybe keep storing these?)
	for _, adr := range ts.Adrs {
		// iterate through all our addresses
		aPKscript, err := txscript.PayToAddrScript(adr.PkhAdr)
		if err != nil {
			return hits, err
		}
		// iterate through all outputs of this tx
		for i, out := range tx.TxOut {
			if bytes.Equal(out.PkScript, aPKscript) { // new utxo for us
				var newu Utxo
				newu.AtHeight = height
				newu.KeyIdx = adr.KeyIdx
				newu.Value = out.Value
				var newop wire.OutPoint
				newop.Hash = tx.TxSha()
				newop.Index = uint32(i)
				newu.Op = newop
				b, err := newu.ToBytes()
				if err != nil {
					return hits, err
				}
				nUtxoBytes = append(nUtxoBytes, b)
				hits++
				break // only one match
			}
		}
	}

	err = ts.StateDB.Update(func(btx *bolt.Tx) error {
		// get all 4 buckets
		duf := btx.Bucket(BKTUtxos)
		//		sta := btx.Bucket(BKTState)
		old := btx.Bucket(BKTStxos)
		txns := btx.Bucket(BKTTxns)
		if duf == nil || old == nil || txns == nil {
			return fmt.Errorf("error: db not initialized")
		}

		// first see if we lose utxos
		// iterate through duffel bag and look for matches
		// this makes us lose money, which is regrettable, but we need to know.
		for _, nOP := range spentOPs {
			duf.ForEach(func(k, v []byte) error {
				if bytes.Equal(k, nOP) { // matched, we lost utxo
					// do all this just to figure out value we lost
					x := make([]byte, len(k)+len(v))
					copy(x, k)
					copy(x[len(k):], v)
					lostTxo, err := UtxoFromBytes(x)
					if err != nil {
						return err
					}
					hits++
					// then delete the utxo from duf, save to old
					err = duf.Delete(k)
					if err != nil {
						return err
					}
					// after deletion, save stxo to old bucket
					var st Stxo               // generate spent txo
					st.Utxo = lostTxo         // assign outpoint
					st.SpendHeight = height   // spent at height
					st.SpendTxid = tx.TxSha() // spent by txid
					stxb, err := st.ToBytes() // serialize
					if err != nil {
						return err
					}
					err = old.Put(k, stxb) // write k:v outpoint:stxo bytes
					if err != nil {
						return err
					}
					// store this relevant tx
					sha := tx.TxSha()
					var buf bytes.Buffer
					tx.Serialize(&buf)
					err = txns.Put(sha.Bytes(), buf.Bytes())
					if err != nil {
						return err
					}

					return nil // matched utxo k, won't match another
				}
				return nil // no match
			})
		} // done losing utxos, next gain utxos
		// next add all new utxos to db, this is quick as the work is above
		for _, ub := range nUtxoBytes {
			err = duf.Put(ub[:36], ub[36:])
			if err != nil {
				return err
			}
		}
		return nil
	})
	return hits, err
}