lnd.xprv/lnwallet/reservation.go
Olaoluwa Osuntokun e762d328fa lnwallet: add ChannelContribution, finalize ChannelReservation API/workflow
* Final workflow has been greatly simplified.
* Interaction is now:
   * init
   * add contribution
   * complete
2015-12-22 22:30:11 -06:00

368 lines
9.7 KiB
Go

package lnwallet
import (
"sync"
"github.com/btcsuite/btcd/btcec"
"github.com/btcsuite/btcd/wire"
"github.com/btcsuite/btcutil"
)
// ChannelContribution...
type ChannelContribution struct {
// Amount of funds contributed to the funding transaction.
FundingAmount btcutil.Amount
// Inputs to the funding transaction.
Inputs []*wire.TxIn
// Outputs to be used in the case that the total value of the fund
// ing inputs is greather than the total potential channel capacity.
ChangeOutputs []*wire.TxOut
// The key to be used for the funding transaction's P2SH multi-sig
// 2-of-2 output.
MultiSigKey *btcec.PublicKey
// The key to be used for this party's version of the commitment
// transaction.
CommitKey *btcec.PublicKey
// Address to be used for delivery of cleared channel funds in the scenario
// of a cooperative channel closure.
DeliveryAddress btcutil.Address
// Hash to be used as the revocation for the initial version of this
// party's commitment transaction.
RevocationHash [wire.HashSize]byte
// The delay (in blocks) to be used for the pay-to-self output in this
// party's version of the commitment transaction.
CsvDelay int64
}
// ChannelReservation...
type ChannelReservation struct {
fundingType FundingType
// This mutex MUST be held when either reading or modifying any of the
// fields below.
sync.RWMutex
// For CLTV it is nLockTime, for CSV it's nSequence, for segwit it's
// not needed
fundingLockTime int64
// In order of sorted inputs. Sorting is done in accordance
// to BIP-69: https://github.com/bitcoin/bips/blob/master/bip-0069.mediawiki.
ourFundingSigs [][]byte
theirFundingSigs [][]byte
// Our signature for their version of the commitment transaction.
ourCommitmentSig []byte
ourContribution *ChannelContribution
theirContribution *ChannelContribution
partialState *OpenChannelState
// The ID of this reservation, used to uniquely track the reservation
// throughout its lifetime.
reservationID uint64
// A channel which will be sent on once the channel is considered
// 'open'. A channel is open once the funding transaction has reached
// a sufficient number of confirmations.
chanOpen chan *LightningChannel
wallet *LightningWallet
}
// newChannelReservation...
func newChannelReservation(t FundingType, fundingAmt btcutil.Amount,
minFeeRate btcutil.Amount, wallet *LightningWallet, id uint64) *ChannelReservation {
// TODO(roasbeef): CSV here, or on delay?
return &ChannelReservation{
fundingType: t,
ourContribution: &ChannelContribution{
FundingAmount: fundingAmt,
},
theirContribution: &ChannelContribution{
FundingAmount: fundingAmt,
},
partialState: &OpenChannelState{
// TODO(roasbeef): assumes balanced symmetric channels.
capacity: fundingAmt * 2,
minFeePerKb: minFeeRate,
},
reservationID: id,
wallet: wallet,
}
}
// OurContribution...
// NOTE: This SHOULD NOT be modified.
func (r *ChannelReservation) OurContribution() *ChannelContribution {
r.RLock()
defer r.RUnlock()
return r.ourContribution
}
// ProcessContribution...
func (r *ChannelReservation) ProcessContribution(theirContribution *ChannelContribution) error {
errChan := make(chan error, 1)
r.wallet.msgChan <- &addContributionMsg{
pendingFundingID: r.reservationID,
contribution: theirContribution,
err: errChan,
}
return <-errChan
}
func (r *ChannelReservation) TheirContribution() *ChannelContribution {
r.RLock()
defer r.RUnlock()
return r.theirContribution
}
// OurSignatures...
func (r *ChannelReservation) OurSignatures() ([][]byte, []byte) {
r.RLock()
defer r.RUnlock()
return r.ourFundingSigs, r.ourCommitmentSig
}
// CompleteFundingReservation...
// TODO(roasbeef): add commit sig also
func (r *ChannelReservation) CompleteReservation(fundingSigs [][]byte, commitmentSig []byte) error {
errChan := make(chan error, 1)
r.wallet.msgChan <- &addCounterPartySigsMsg{
pendingFundingID: r.reservationID,
theirFundingSigs: fundingSigs,
theirCommitmentSig: commitmentSig,
err: errChan,
}
return <-errChan
}
// OurSignatures...
func (r *ChannelReservation) TheirSignatures() ([][]byte, []byte) {
r.RLock()
defer r.RUnlock()
return r.theirFundingSigs, r.partialState.theirCommitSig
}
// FinalFundingTransaction...
func (r *ChannelReservation) FinalFundingTx() *wire.MsgTx {
r.RLock()
defer r.RUnlock()
return r.partialState.fundingTx
}
// RequestFundingReserveCancellation...
// TODO(roasbeef): also return mutated state?
func (r *ChannelReservation) Cancel() error {
errChan := make(chan error, 1)
r.wallet.msgChan <- &fundingReserveCancelMsg{
pendingFundingID: r.reservationID,
err: errChan,
}
return <-errChan
}
// WaitForChannelOpen...
func (r *ChannelReservation) WaitForChannelOpen() *LightningChannel {
return nil
}
/*//FundRequest serialize
//(reading from ChannelReservation directly to reduce the amount of copies)
//We can move this stuff to another file too if it's too big...
func (r *ChannelReservation) SerializeFundRequest() ([]byte, error) {
var err error
//Buffer to dump in the serialized data
b := new(bytes.Buffer)
//Fund Request
err = b.WriteByte(0x30)
if err != nil {
return nil, err
}
//ChannelType (1)
//Default to current type
err = b.WriteByte(uint8(0))
if err != nil {
return nil, err
}
//RequesterFundingAmount - The amount we are going to fund (8)
//check for positive values
err = binary.Write(b, binary.BigEndian, r.FundingAmount)
if err != nil {
return nil, err
}
//RequesterChannelMinCapacity (8)
//The amount needed to accept and sign the channel commit later
err = binary.Write(b, binary.BigEndian, r.MinTotalFundingAmount)
if err != nil {
return nil, err
}
//RevocationHash (20)
//Our revocation hash being contributed (for CLTV/CSV)
_, err = b.Write(btcutil.Hash160(r.ourRevocation))
if err != nil {
return nil, err
}
//CommitPubkey (33)
//Our public key being used for the commitment
ourPubKey := r.ourKey.PubKey().SerializeCompressed()
if len(ourPubKey) != 33 { //validation, can remove later? (NO UNCOMPRESSED KEYS!)
return nil, fmt.Errorf("Serialize FundReq: our Pubkey length incorrect")
}
_, err = b.Write(ourPubKey)
if err != nil {
return nil, err
}
//DeliveryPkHash (20)
//For now it's a P2PKH, but we will add an extra byte later for the
//option for P2SH
//This is the address to send funds to when complete or refunded
_, err = b.Write(r.ourDeliveryAddress)
if err != nil {
return nil, err
}
//ReserveAmount (8)
//Our own reserve amount
err = binary.Write(b, binary.BigEndian, r.ReserveAmount)
if err != nil {
return nil, err
}
//Minimum transaction fee per kb (8)
err = binary.Write(b, binary.BigEndian, r.MinFeePerKb)
if err != nil {
return nil, err
}
//LockTime (4)
err = binary.Write(b, binary.BigEndian, r.FundingLockTime)
if err != nil {
return nil, err
}
//Fee payer (default to split currently) (1)
err = binary.Write(b, binary.BigEndian, 0)
if err != nil {
return nil, err
}
//ChangePkScript
//Length (1)
changeScriptLength := len(r.ourChange[0].PkScript)
if changeScriptLength > 255 {
return nil, fmt.Errorf("Your changeScriptLength is too long!")
}
err = binary.Write(b, binary.BigEndian, uint8(changeScriptLength))
if err != nil {
return nil, err
}
//For now it's a P2PKH, but we will add an extra byte later for the
//option for P2SH
//This is the address to send change to (only allow one)
//ChangePkScript (length of script)
_, err = b.Write(r.ourChange[0].PkScript)
if err != nil {
return nil, err
}
//Append the unsigned(!!) txins
//First one byte for the amount of txins (1)
if len(r.ourInputs) > 127 {
return nil, fmt.Errorf("Too many txins")
}
err = b.WriteByte(uint8(len(r.ourInputs)))
if err != nil {
return nil, err
}
//Append the actual Txins (NumOfTxins * 36)
//Do not include the sequence number to eliminate funny business
for _, in := range r.ourInputs {
//Hash
_, err = b.Write(in.PreviousOutPoint.Hash.Bytes())
if err != nil {
return nil, err
}
//Index
err = binary.Write(b, binary.BigEndian, in.PreviousOutPoint.Index)
if err != nil {
return nil, err
}
}
return b.Bytes(), err
}
func (r *ChannelReservation) DeserializeFundRequest(wireMsg []byte) error {
//Make sure we're not overwriting stuff...
//Update the channelState to 1 before progressing if you want to re-do it.
//Assumes only one thread is writing at a time
if r.channelState > 1 {
return fmt.Errorf("FundRequest: Channel State Mismatch")
}
var err error
b := bytes.NewBuffer(wireMsg)
msgid, _ := b.ReadByte()
if msgid != 0x30 {
return fmt.Errorf("Cannot deserialize: not a funding request")
}
if err != nil {
return err
}
//Update the channel state as complete
r.channelState = 2
return nil
}
//Validation on the data being supplied from the fund request
func (r *ChannelReservation) ValidateFundRequest(wireMsg []byte) error {
return nil
}
//Serialize CSV Revocation
//After the Commitment Transaction has been created, send a message to revoke this tx
func (r *ChannelReservation) SerializeCSVRefundRevocation() ([]byte, error) {
return nil, nil
}
//Deserialize CSV Revocation
//Validate the revocation, after this step, the channel is fully set up
func (r *ChannelReservation) DeserializeCSVRefundRevocation() error {
return nil
}*/
// * finish reset of tests
// * comment out stuff that'll need a node.
// * start on commitment side
// * implement rusty's shachain
// * set up logic to get notification from node when funding tx gets 6 deep.
// * prob spawn into ChainNotifier struct
// * create builder for initial funding transaction
// * fascade through the wallet, for signing and such.
// * channel should have active namespace to it's bucket, query at that point fo past commits etc