lnd.xprv/channeldb/channel.go

2404 lines
72 KiB
Go

package channeldb
import (
"bytes"
"encoding/binary"
"fmt"
"io"
"net"
"sync"
"github.com/boltdb/bolt"
"github.com/lightningnetwork/lnd/lnwire"
"github.com/lightningnetwork/lnd/shachain"
"github.com/roasbeef/btcd/btcec"
"github.com/roasbeef/btcd/chaincfg/chainhash"
"github.com/roasbeef/btcd/wire"
"github.com/roasbeef/btcutil"
)
var (
// openChanBucket stores all the currently open channels. This bucket
// has a second, nested bucket which is keyed by a node's ID. Additionally,
// at the base level of this bucket several prefixed keys are stored which
// house channel metadata such as total satoshis sent, number of updates
// etc. These fields are stored at this top level rather than within a
// node's channel bucket in order to facilitate sequential prefix scans
// to gather stats such as total satoshis received.
openChannelBucket = []byte("ocb")
// chanIDBucket is a third-level bucket stored within a node's ID bucket
// in the open channel bucket. The resolution path looks something like:
// ocb -> nodeID -> cib. This bucket contains a series of keys with no
// values, these keys are the channel ID's of all the active channels
// we currently have with a specified nodeID. This bucket acts as an
// additional indexing allowing random access and sequential scans over
// active channels.
chanIDBucket = []byte("cib")
// closedChannelBucket stores summarization information concerning
// previously open, but now closed channels.
closedChannelBucket = []byte("ccb")
// channelLogBucket is dedicated for storing the necessary delta state
// between channel updates required to re-construct a past state in
// order to punish a counterparty attempting a non-cooperative channel
// closure. A channel log bucket is created for each node and is nested
// within a node's ID bucket.
channelLogBucket = []byte("clb")
// identityKey is the key for storing this node's current LD identity
// key.
identityKey = []byte("idk")
// The following prefixes are stored at the base level within the
// openChannelBucket. In order to retrieve a particular field for an
// active, or historic channel, append the channels ID to the prefix:
// key = prefix || chanID. Storing certain fields at the top level
// using a prefix scheme serves two purposes: first to facilitate
// sequential prefix scans, and second to eliminate write amplification
// caused by serializing/deserializing the *entire* struct with each
// update.
chanCapacityPrefix = []byte("ccp")
selfBalancePrefix = []byte("sbp")
theirBalancePrefix = []byte("tbp")
minFeePerKwPrefix = []byte("mfp")
chanConfigPrefix = []byte("chan-config")
updatePrefix = []byte("uup")
satSentPrefix = []byte("ssp")
satReceivedPrefix = []byte("srp")
commitFeePrefix = []byte("cfp")
isPendingPrefix = []byte("pdg")
confInfoPrefix = []byte("conf-info")
// chanIDKey stores the node, and channelID for an active channel.
chanIDKey = []byte("cik")
// commitKeys stores both commitment keys (ours, and theirs) for an
// active channel. Our private key is stored in an encrypted format
// using channeldb's currently registered cryptoSystem.
commitKeys = []byte("ckk")
// commitTxnsKey stores the full version of both current, non-revoked
// commitment transactions in addition to the csvDelay for both.
commitTxnsKey = []byte("ctk")
// currentHtlcKey stores the set of fully locked-in HTLCs on our latest
// commitment state.
currentHtlcKey = []byte("chk")
// fundingTxnKey stores the funding output, the multi-sig keys used in
// the funding output, and further information detailing if the
// transaction is "open", or not and how many confirmations required
// until it's considered open.
fundingTxnKey = []byte("fsk")
// revocationStateKey stores their current revocation hash, our
// preimage producer and their preimage store.
revocationStateKey = []byte("esk")
)
// ChannelType is an enum-like type that describes one of several possible
// channel types. Each open channel is associated with a particular type as the
// channel type may determine how higher level operations are conducted such as
// fee negotiation, channel closing, the format of HTLCs, etc.
// TODO(roasbeef): split up per-chain?
type ChannelType uint8
const (
// NOTE: iota isn't used here for this enum needs to be stable
// long-term as it will be persisted to the database.
// SingleFunder represents a channel wherein one party solely funds the
// entire capacity of the channel.
SingleFunder = 0
// DualFunder represents a channel wherein both parties contribute
// funds towards the total capacity of the channel. The channel may be
// funded symmetrically or asymmetrically.
DualFunder = 1
)
// ChannelConstraints represents a set of constraints meant to allow a node to
// limit their exposure, enact flow control and ensure that all HTLC's are
// economically relevant This struct will be mirrored for both sides of the
// channel, as each side will enforce various constraints that MUST be adhered
// to for the life time of the channel. The parameters for each of these
// constraints is static for the duration of the channel, meaning the channel
// must be teared down for them to change.
type ChannelConstraints struct {
// DustLimit is the threhsold (in satoshis) below which any outputs
// should be trimmed. When an output is trimmed, it isn't materialized
// as an actual output, but is instead burned to miner's fees.
DustLimit btcutil.Amount
// MaxPendingAmount is the maximum pending HTLC value that can be
// present within the channel at a particular time. This value is set
// by the initiator of the channel and must be upheld at all times.
MaxPendingAmount lnwire.MilliSatoshi
// ChanReserve is an absolute reservation on the channel for this
// particular node. This means that the current settled balance for
// this node CANNOT dip below the reservation amount. This acts as a
// defense against costless attacks when either side no longer has any
// skin in the game.
//
// TODO(roasbeef): need to swap above, i tell them what reserve, then
// other way around
ChanReserve btcutil.Amount
// MinHTLC is the minimum HTLC accepted for a direction of the channel.
// If any HTLC's below this amount are offered, then the HTLC will be
// rejected. This, in tandem with the dust limit allows a node to
// regulate the smallest HTLC that it deems economically relevant.
MinHTLC lnwire.MilliSatoshi
// MaxAcceptedHtlcs is the maximum amount of HTLC's that are to be
// accepted by the owner of this set of constraints. This allows each
// node to limit their over all exposure to HTLC's that may need to be
// acted upon in the case of a unilateral channel closure or a contract
// breach.
MaxAcceptedHtlcs uint16
}
// ChannelConfig is a struct that houses the various configuration opens for
// channels. Each side maintains an instance of this configuration file as it
// governs: how the funding and commitment transaction to be created, the
// nature of HTLC's allotted, the keys to be used for delivery, and relative
// time lock parameters.
type ChannelConfig struct {
// ChannelConstraints is the set of constraints that must be upheld for
// the duration of the channel for ths owner of this channel
// configuration. Constraints govern a number of flow control related
// parameters, also including the smallest HTLC that will be accepted
// by a participant.
ChannelConstraints
// CsvDelay is the relative time lock delay expressed in blocks. Any
// settled outputs that pay to the owner of this channel configuration
// MUST ensure that the delay branch uses this value as the relative
// time lock. Similarly, any HTLC's offered by this node should use
// this value as well.
CsvDelay uint16
// MultiSigKey is the key to be used within the 2-of-2 output script
// for the owner of this channel config.
MultiSigKey *btcec.PublicKey
// RevocationBasePoint is the base public key to be used when deriving
// revocation keys for the remote node's commitment transaction. This
// will be combined along with a per commitment secret to derive a
// unique revocation key for each state.
RevocationBasePoint *btcec.PublicKey
// PaymentBasePoint is the based public key to be used when deriving
// the key used within the non-delayed pay-to-self output on the
// commitment transaction for a node. This will be combined with a
// tweak derived from the per-commitment point to ensure unique keys
// for each commitment transaction.
PaymentBasePoint *btcec.PublicKey
// DelayBasePoint is the based public key to be used when deriving the
// key used within the delayed pay-to-self output on the commitment
// transaction for a node. This will be combined with a tweak derived
// from the per-commitment point to ensure unique keys for each
// commitment transaction.
DelayBasePoint *btcec.PublicKey
}
// OpenChannel encapsulates the persistent and dynamic state of an open channel
// with a remote node. An open channel supports several options for on-disk
// serialization depending on the exact context. Full (upon channel creation)
// state commitments, and partial (due to a commitment update) writes are
// supported. Each partial write due to a state update appends the new update
// to an on-disk log, which can then subsequently be queried in order to
// "time-travel" to a prior state.
type OpenChannel struct {
// ChanType denotes which type of channel this is.
ChanType ChannelType
// ChainHash is a hash which represents the blockchain that this
// channel will be opened within. This value is typically the genesis
// hash. In the case that the original chain went through a contentious
// hard-fork, then this value will be tweaked using the unique fork
// point on each branch.
ChainHash chainhash.Hash
// FundingOutpoint is the outpoint of the final funding transaction.
// This value uniquely and globally identities the channel within the
// target blockchain as specified by the chain hash parameter.
FundingOutpoint wire.OutPoint
// ShortChanID encodes the exact location in the chain in which the
// channel was initially confirmed. This includes: the block height,
// transaction index, and the output within the target transaction.
ShortChanID lnwire.ShortChannelID
// IsPending indicates whether a channel's funding transaction has been
// confirmed.
IsPending bool
// IsInitiator is a bool which indicates if we were the original
// initiator for the channel. This value may affect how higher levels
// negotiate fees, or close the channel.
IsInitiator bool
// FundingBroadcastHeight is the height in which the funding
// transaction was broadcast. This value can be used by higher level
// sub-systems to determine if a channel is stale and/or should have
// been confirmed before a certain height.
FundingBroadcastHeight uint32
// IdentityPub is the identity public key of the remote node this
// channel has been established with.
IdentityPub *btcec.PublicKey
// LocalChanCfg is the channel configuration for the local node.
LocalChanCfg ChannelConfig
// RemoteChanCfg is the channel configuration for the remote node.
RemoteChanCfg ChannelConfig
// FeePerKw is the min satoshis/kilo-weight that should be paid within
// the commitment transaction for the entire duration of the channel's
// lifetime. This field may be updated during normal operation of the
// channel as on-chain conditions change.
FeePerKw btcutil.Amount
// Capacity is the total capacity of this channel.
Capacity btcutil.Amount
// LocalBalance is the current available settled balance within the
// channel directly spendable by us.
LocalBalance lnwire.MilliSatoshi
// RemoteBalance is the current available settled balance within the
// channel directly spendable by the remote node.
RemoteBalance lnwire.MilliSatoshi
// CommitFee is the amount calculated to be paid in fees for the
// current set of commitment transactions. The fee amount is persisted
// with the channel in order to allow the fee amount to be removed and
// recalculated with each channel state update, including updates that
// happen after a system restart.
CommitFee btcutil.Amount
// CommitKey is the latest version of the commitment state, broadcast
// able by us.
CommitTx wire.MsgTx
// CommitSig is one half of the signature required to fully complete
// the script for the commitment transaction above. This is the
// signature signed by the remote party for our version of the
// commitment transactions.
CommitSig []byte
// NumConfsRequired is the number of confirmations a channel's funding
// transaction must have received in order to be considered available
// for normal transactional use.
NumConfsRequired uint16
// RemoteCurrentRevocation is the current revocation for their
// commitment transaction. However, since this the derived public key,
// we don't yet have the private key so we aren't yet able to verify
// that it's actually in the hash chain.
RemoteCurrentRevocation *btcec.PublicKey
// RemoteNextRevocation is the revocation key to be used for the *next*
// commitment transaction we create for the local node. Within the
// specification, this value is referred to as the
// per-commitment-point.
RemoteNextRevocation *btcec.PublicKey
// RevocationProducer is used to generate the revocation in such a way
// that remote side might store it efficiently and have the ability to
// restore the revocation by index if needed. Current implementation of
// secret producer is shachain producer.
RevocationProducer shachain.Producer
// RevocationStore is used to efficiently store the revocations for
// previous channels states sent to us by remote side. Current
// implementation of secret store is shachain store.
RevocationStore shachain.Store
// NumUpdates is the total number of updates conducted within this
// channel.
NumUpdates uint64
// TotalMSatSent is the total number of milli-satoshis we've sent
// within this channel.
TotalMSatSent lnwire.MilliSatoshi
// TotalMSatReceived is the total number of milli-satoshis we've
// received within this channel.
TotalMSatReceived lnwire.MilliSatoshi
// Htlcs is the list of active, uncleared HTLCs currently pending
// within the channel.
Htlcs []*HTLC
// TODO(roasbeef): eww
Db *DB
sync.RWMutex
}
// FullSync serializes, and writes to disk the *full* channel state, using
// both the active channel bucket to store the prefixed column fields, and the
// remote node's ID to store the remainder of the channel state.
func (c *OpenChannel) FullSync() error {
c.Lock()
defer c.Unlock()
return c.Db.Update(c.fullSync)
}
// fullSync is an internal versino of the FullSync method which allows callers
// to sync the contents of an OpenChannel while re-using an existing database
// transaction.
func (c *OpenChannel) fullSync(tx *bolt.Tx) error {
// TODO(roasbeef): add helper funcs to create scoped update
// First fetch the top level bucket which stores all data related to
// current, active channels.
chanBucket, err := tx.CreateBucketIfNotExists(openChannelBucket)
if err != nil {
return err
}
// Within this top level bucket, fetch the bucket dedicated to storing
// open channel data specific to the remote node.
nodePub := c.IdentityPub.SerializeCompressed()
nodeChanBucket, err := chanBucket.CreateBucketIfNotExists(nodePub)
if err != nil {
return err
}
// Add this channel ID to the node's active channel index if
// it doesn't already exist.
chanIndexBucket, err := nodeChanBucket.CreateBucketIfNotExists(chanIDBucket)
if err != nil {
return err
}
var b bytes.Buffer
if err := writeOutpoint(&b, &c.FundingOutpoint); err != nil {
return err
}
if chanIndexBucket.Get(b.Bytes()) == nil {
if err := chanIndexBucket.Put(b.Bytes(), nil); err != nil {
return err
}
}
return putOpenChannel(chanBucket, nodeChanBucket, c)
}
// SyncPending writes the contents of the channel to the database while it's in
// the pending (waiting for funding confirmation) state. The IsPending flag
// will be set to true. When the channel's funding transaction is confirmed,
// the channel should be marked as "open" and the IsPending flag set to false.
// Note that this function also creates a LinkNode relationship between this
// newly created channel and a new LinkNode instance. This allows listing all
// channels in the database globally, or according to the LinkNode they were
// created with.
//
// TODO(roasbeef): addr param should eventually be a lnwire.NetAddress type
// that includes service bits.
func (c *OpenChannel) SyncPending(addr *net.TCPAddr, pendingHeight uint32) error {
c.Lock()
defer c.Unlock()
c.FundingBroadcastHeight = pendingHeight
return c.Db.Update(func(tx *bolt.Tx) error {
// First, sync all the persistent channel state to disk.
if err := c.fullSync(tx); err != nil {
return err
}
nodeInfoBucket, err := tx.CreateBucketIfNotExists(nodeInfoBucket)
if err != nil {
return err
}
// If a LinkNode for this identity public key already exists,
// then we can exit early.
nodePub := c.IdentityPub.SerializeCompressed()
if nodeInfoBucket.Get(nodePub) != nil {
return nil
}
// Next, we need to establish a (possibly) new LinkNode
// relationship for this channel. The LinkNode metadata
// contains reachability, up-time, and service bits related
// information.
// TODO(roasbeef): net info should be in lnwire.NetAddress
linkNode := c.Db.NewLinkNode(wire.MainNet, c.IdentityPub, addr)
return putLinkNode(nodeInfoBucket, linkNode)
})
}
// UpdateCommitment updates the on-disk state of our currently broadcastable
// commitment state. This method is to be called once we have revoked our prior
// commitment state, accepting the new state as defined by the passed
// parameters.
func (c *OpenChannel) UpdateCommitment(newCommitment *wire.MsgTx,
newSig []byte, delta *ChannelDelta) error {
c.Lock()
defer c.Unlock()
return c.Db.Update(func(tx *bolt.Tx) error {
chanBucket, err := tx.CreateBucketIfNotExists(openChannelBucket)
if err != nil {
return err
}
id := c.IdentityPub.SerializeCompressed()
nodeChanBucket, err := chanBucket.CreateBucketIfNotExists(id)
if err != nil {
return err
}
// TODO(roasbeef): modify the funcs below to take values
// directly, otherwise need to roll back to prior state. Could
// also make copy above, then modify to pass in.
c.CommitTx = *newCommitment
c.CommitSig = newSig
c.LocalBalance = delta.LocalBalance
c.RemoteBalance = delta.RemoteBalance
c.NumUpdates = delta.UpdateNum
c.Htlcs = delta.Htlcs
c.CommitFee = delta.CommitFee
c.FeePerKw = delta.FeePerKw
// First we'll write out the current latest dynamic channel
// state: the current channel balance, the number of updates,
// and our latest commitment transaction+sig.
// TODO(roasbeef): re-make schema s.t this is a single put
if err := putChanCapacity(chanBucket, c); err != nil {
return err
}
if err := putChanAmountsTransferred(chanBucket, c); err != nil {
return err
}
if err := putChanNumUpdates(chanBucket, c); err != nil {
return err
}
if err := putChanCommitFee(chanBucket, c); err != nil {
return err
}
if err := putChanFeePerKw(chanBucket, c); err != nil {
return err
}
if err := putChanCommitTxns(nodeChanBucket, c); err != nil {
return err
}
if err := putCurrentHtlcs(nodeChanBucket, delta.Htlcs,
&c.FundingOutpoint); err != nil {
return err
}
return nil
})
}
// HTLC is the on-disk representation of a hash time-locked contract. HTLCs
// are contained within ChannelDeltas which encode the current state of the
// commitment between state updates.
type HTLC struct {
// Signature is the signature for the second level covenant transaction
// for this HTLC. The second level transaction is a timeout tx in the
// case that this is an outgoing HTLC, and a success tx in the case
// that this is an incoming HTLC.
//
// TODO(roasbeef): make [64]byte instead?
Signature []byte
// RHash is the payment hash of the HTLC.
RHash [32]byte
// Amt is the amount of milli-satoshis this HTLC escrows.
Amt lnwire.MilliSatoshi
// RefundTimeout is the absolute timeout on the HTLC that the sender
// must wait before reclaiming the funds in limbo.
RefundTimeout uint32
// OutputIndex is the output index for this particular HTLC output
// within the commitment transaction.
OutputIndex int32
// Incoming denotes whether we're the receiver or the sender of this
// HTLC.
Incoming bool
}
// Copy returns a full copy of the target HTLC.
func (h *HTLC) Copy() HTLC {
clone := HTLC{
Incoming: h.Incoming,
Amt: h.Amt,
RefundTimeout: h.RefundTimeout,
OutputIndex: h.OutputIndex,
}
copy(clone.Signature[:], h.Signature)
copy(clone.RHash[:], h.RHash[:])
return clone
}
// ChannelDelta is a snapshot of the commitment state at a particular point in
// the commitment chain. With each state transition, a snapshot of the current
// state along with all non-settled HTLCs are recorded. These snapshots detail
// the state of the _remote_ party's commitment at a particular state number.
// For ourselves (the local node) we ONLY store our most recent (unrevoked)
// state for safety purposes.
type ChannelDelta struct {
// LocalBalance is our current balance at this particular update
// number.
LocalBalance lnwire.MilliSatoshi
// RemoteBalanceis the balance of the remote node at this particular
// update number.
RemoteBalance lnwire.MilliSatoshi
// CommitFee is the fee that has been subtracted from the channel
// initiator's balance at this point in the commitment chain.
CommitFee btcutil.Amount
// FeePerKw is the fee per kw used to calculate the commit fee at this point
// in the commit chain.
FeePerKw btcutil.Amount
// UpdateNum is the update number that this ChannelDelta represents the
// total number of commitment updates to this point. This can be viewed
// as sort of a "commitment height" as this number is monotonically
// increasing.
UpdateNum uint64
// Htlcs is the set of HTLC's that are pending at this particular
// commitment height.
Htlcs []*HTLC
}
// InsertNextRevocation inserts the _next_ commitment point (revocation) into
// the database, and also modifies the internal RemoteNextRevocation attribute
// to point to the passed key. This method is to be using during final channel
// set up, _after_ the channel has been fully confirmed.
//
// NOTE: If this method isn't called, then the target channel won't be able to
// propose new states for the commitment state of the remote party.
func (c *OpenChannel) InsertNextRevocation(revKey *btcec.PublicKey) error {
c.Lock()
defer c.Unlock()
return c.Db.Update(func(tx *bolt.Tx) error {
chanBucket, err := tx.CreateBucketIfNotExists(openChannelBucket)
if err != nil {
return err
}
id := c.IdentityPub.SerializeCompressed()
nodeChanBucket, err := chanBucket.CreateBucketIfNotExists(id)
if err != nil {
return err
}
c.RemoteNextRevocation = revKey
return putChanRevocationState(nodeChanBucket, c)
})
}
// AppendToRevocationLog records the new state transition within an on-disk
// append-only log which records all state transitions by the remote peer. In
// the case of an uncooperative broadcast of a prior state by the remote peer,
// this log can be consulted in order to reconstruct the state needed to
// rectify the situation.
func (c *OpenChannel) AppendToRevocationLog(delta *ChannelDelta) error {
return c.Db.Update(func(tx *bolt.Tx) error {
chanBucket, err := tx.CreateBucketIfNotExists(openChannelBucket)
if err != nil {
return err
}
id := c.IdentityPub.SerializeCompressed()
nodeChanBucket, err := chanBucket.CreateBucketIfNotExists(id)
if err != nil {
return err
}
// Persist the latest preimage state to disk as the remote peer
// has just added to our local preimage store, and
// given us a new pending revocation key.
if err := putChanRevocationState(nodeChanBucket, c); err != nil {
return err
}
// With the current preimage producer/store state updated,
// append a new log entry recording this the delta of this state
// transition.
// TODO(roasbeef): could make the deltas relative, would save
// space, but then tradeoff for more disk-seeks to recover the
// full state.
logKey := channelLogBucket
logBucket, err := nodeChanBucket.CreateBucketIfNotExists(logKey)
if err != nil {
return err
}
return appendChannelLogEntry(logBucket, delta, &c.FundingOutpoint)
})
}
// RevocationLogTail returns the "tail", or the end of the current revocation
// log. This entry represents the last previous state for the remote node's
// commitment chain. The ChannelDelta returned by this method will always lag
// one state behind the most current (unrevoked) state of the remote node's
// commitment chain.
func (c *OpenChannel) RevocationLogTail() (*ChannelDelta, error) {
// If we haven't created any state updates yet, then we'll exit erly as
// there's nothing to be found on disk in the revocation bucket.
if c.NumUpdates == 0 {
return nil, nil
}
var delta *ChannelDelta
if err := c.Db.View(func(tx *bolt.Tx) error {
chanBucket := tx.Bucket(openChannelBucket)
nodePub := c.IdentityPub.SerializeCompressed()
nodeChanBucket := chanBucket.Bucket(nodePub)
if nodeChanBucket == nil {
return ErrNoActiveChannels
}
logBucket := nodeChanBucket.Bucket(channelLogBucket)
if logBucket == nil {
return ErrNoPastDeltas
}
// Once we have the bucket that stores the revocation log from
// this channel, we'll jump to the _last_ key in bucket. As we
// store the update number on disk in a big-endian format,
// this'll retrieve the latest entry.
cursor := logBucket.Cursor()
_, tailLogEntry := cursor.Last()
logEntryReader := bytes.NewReader(tailLogEntry)
// Once we have the entry, we'll decode it into the channel
// delta pointer we created above.
var dbErr error
delta, dbErr = deserializeChannelDelta(logEntryReader)
if dbErr != nil {
return dbErr
}
return nil
}); err != nil {
return nil, err
}
return delta, nil
}
// CommitmentHeight returns the current commitment height. The commitment
// height represents the number of updates to the commitment state to data.
// This value is always monotonically increasing. This method is provided in
// order to allow multiple instances of a particular open channel to obtain a
// consistent view of the number of channel updates to data.
func (c *OpenChannel) CommitmentHeight() (uint64, error) {
// TODO(roasbeef): this is super hacky, remedy during refactor!!!
o := &OpenChannel{
FundingOutpoint: c.FundingOutpoint,
}
err := c.Db.View(func(tx *bolt.Tx) error {
// Get the bucket dedicated to storing the metadata for open
// channels.
openChanBucket := tx.Bucket(openChannelBucket)
if openChanBucket == nil {
return ErrNoActiveChannels
}
return fetchChanNumUpdates(openChanBucket, o)
})
if err != nil {
return 0, nil
}
return o.NumUpdates, nil
}
// FindPreviousState scans through the append-only log in an attempt to recover
// the previous channel state indicated by the update number. This method is
// intended to be used for obtaining the relevant data needed to claim all
// funds rightfully spendable in the case of an on-chain broadcast of the
// commitment transaction.
func (c *OpenChannel) FindPreviousState(updateNum uint64) (*ChannelDelta, error) {
delta := &ChannelDelta{}
err := c.Db.View(func(tx *bolt.Tx) error {
chanBucket := tx.Bucket(openChannelBucket)
nodePub := c.IdentityPub.SerializeCompressed()
nodeChanBucket := chanBucket.Bucket(nodePub)
if nodeChanBucket == nil {
return ErrNoActiveChannels
}
logBucket := nodeChanBucket.Bucket(channelLogBucket)
if logBucket == nil {
return ErrNoPastDeltas
}
var err error
delta, err = fetchChannelLogEntry(logBucket, &c.FundingOutpoint,
updateNum)
return err
})
if err != nil {
return nil, err
}
return delta, nil
}
// ClosureType is an enum like structure that details exactly _how_ a channel
// was closed. Three closure types are currently possible: cooperative, force,
// and breach.
type ClosureType uint8
const (
// CooperativeClose indicates that a channel has been closed
// cooperatively. This means that both channel peers were online and
// signed a new transaction paying out the settled balance of the
// contract.
CooperativeClose ClosureType = iota
// ForceClose indicates that one peer unilaterally broadcast their
// current commitment state on-chain.
ForceClose
// BreachClose indicates that one peer attempted to broadcast a prior
// _revoked_ channel state.
BreachClose
// FundingCanceled indicates that the channel never was fully opened before it
// was marked as closed in the database. This can happen if we or the remote
// fail at some point during the opening workflow, or we timeout waiting for
// the funding transaction to be confirmed.
FundingCanceled
)
// ChannelCloseSummary contains the final state of a channel at the point it
// was close. Once a channel is closed, all the information pertaining to that
// channel within the openChannelBucket is deleted, and a compact summary is
// but in place instead.
type ChannelCloseSummary struct {
// ChanPoint is the outpoint for this channel's funding transaction,
// and is used as a unique identifier for the channel.
ChanPoint wire.OutPoint
// ClosingTXID is the txid of the transaction which ultimately closed
// this channel.
ClosingTXID chainhash.Hash
// RemotePub is the public key of the remote peer that we formerly had
// a channel with.
RemotePub *btcec.PublicKey
// Capacity was the total capacity of the channel.
Capacity btcutil.Amount
// SettledBalance is our total balance settled balance at the time of
// channel closure. This _does not_ include the sum of any outputs that
// have been time-locked as a result of the unilateral channel closure.
SettledBalance btcutil.Amount
// TimeLockedBalance is the sum of all the time-locked outputs at the
// time of channel closure. If we triggered the force closure of this
// channel, then this value will be non-zero if our settled output is
// above the dust limit. If we were on the receiving side of a channel
// force closure, then this value will be non-zero if we had any
// outstanding outgoing HTLC's at the time of channel closure.
TimeLockedBalance btcutil.Amount
// CloseType details exactly _how_ the channel was closed. Three
// closure types are possible: cooperative, force, and breach.
CloseType ClosureType
// IsPending indicates whether this channel is in the 'pending close'
// state, which means the channel closing transaction has been
// broadcast, but not confirmed yet or has not yet been fully resolved.
// In the case of a channel that has been cooperatively closed, it will
// no longer be considered pending as soon as the closing transaction
// has been confirmed. However, for channel that have been force
// closed, they'll stay marked as "pending" until _all_ the pending
// funds have been swept.
IsPending bool
// TODO(roasbeef): also store short_chan_id?
}
// CloseChannel closes a previously active lightning channel. Closing a channel
// entails deleting all saved state within the database concerning this
// channel. This method also takes a struct that summarizes the state of the
// channel at closing, this compact representation will be the only component
// of a channel left over after a full closing.
func (c *OpenChannel) CloseChannel(summary *ChannelCloseSummary) error {
return c.Db.Update(func(tx *bolt.Tx) error {
// First fetch the top level bucket which stores all data
// related to current, active channels.
chanBucket := tx.Bucket(openChannelBucket)
if chanBucket == nil {
return ErrNoChanDBExists
}
// Within this top level bucket, fetch the bucket dedicated to
// storing open channel data specific to the remote node.
nodePub := c.IdentityPub.SerializeCompressed()
nodeChanBucket := chanBucket.Bucket(nodePub)
if nodeChanBucket == nil {
return ErrNoActiveChannels
}
// Delete this channel ID from the node's active channel index.
chanIndexBucket := nodeChanBucket.Bucket(chanIDBucket)
if chanIndexBucket == nil {
return ErrNoActiveChannels
}
var b bytes.Buffer
if err := writeOutpoint(&b, &c.FundingOutpoint); err != nil {
return err
}
// If this channel isn't found within the channel index bucket,
// then it has already been deleted. So we can exit early as
// there isn't any more work for us to do here.
outPointBytes := b.Bytes()
if chanIndexBucket.Get(outPointBytes) == nil {
return nil
}
// Otherwise, we can safely delete the channel from the index
// without running into any boltdb related errors by repeated
// deletion attempts.
if err := chanIndexBucket.Delete(outPointBytes); err != nil {
return err
}
// Now that the index to this channel has been deleted, purge
// the remaining channel metadata from the database.
if err := deleteOpenChannel(chanBucket, nodeChanBucket,
outPointBytes, &c.FundingOutpoint); err != nil {
return err
}
// With the base channel data deleted, attempt to delte the
// information stored within the revocation log.
logBucket := nodeChanBucket.Bucket(channelLogBucket)
if logBucket != nil {
err := wipeChannelLogEntries(logBucket, &c.FundingOutpoint)
if err != nil {
return err
}
}
// Finally, create a summary of this channel in the closed
// channel bucket for this node.
return putChannelCloseSummary(tx, outPointBytes, summary)
})
}
// ChannelSnapshot is a frozen snapshot of the current channel state. A
// snapshot is detached from the original channel that generated it, providing
// read-only access to the current or prior state of an active channel.
type ChannelSnapshot struct {
// RemoteIdentity is the identity public key of the remote node that we
// are maintaining the open channel with.
RemoteIdentity btcec.PublicKey
// ChannelPoint is the channel point that uniquly identifies the
// channel whose delta this is.
ChannelPoint wire.OutPoint
// Capacity is the total capacity of the channel in satoshis.
Capacity btcutil.Amount
// LocalBalance is the amount of mSAT allocated to the local party.
LocalBalance lnwire.MilliSatoshi
// RemoteBalance is the amount of mSAT allocated to the remote party.
RemoteBalance lnwire.MilliSatoshi
// NumUpdates is the number of updates that have taken place within the
// commitment transaction itself.
NumUpdates uint64
// CommitFee is the total fee paid on the commitment transaction at
// this current commitment state.
CommitFee btcutil.Amount
// TotalMilliSatoshisSent is the total number of mSAT sent by the local
// party at this current commitment instance.
TotalMilliSatoshisSent lnwire.MilliSatoshi
// TotalMilliSatoshisReceived is the total number of mSAT received by
// the local party current commitment instance.
TotalMilliSatoshisReceived lnwire.MilliSatoshi
// Htlcs is the current set of outstanding HTLC's live on the
// commitment transaction at this instance.
Htlcs []HTLC
}
// Snapshot returns a read-only snapshot of the current channel state. This
// snapshot includes information concerning the current settled balance within
// the channel, metadata detailing total flows, and any outstanding HTLCs.
func (c *OpenChannel) Snapshot() *ChannelSnapshot {
c.RLock()
defer c.RUnlock()
snapshot := &ChannelSnapshot{
RemoteIdentity: *c.IdentityPub,
ChannelPoint: c.FundingOutpoint,
Capacity: c.Capacity,
LocalBalance: c.LocalBalance,
RemoteBalance: c.RemoteBalance,
NumUpdates: c.NumUpdates,
CommitFee: c.CommitFee,
TotalMilliSatoshisSent: c.TotalMSatSent,
TotalMilliSatoshisReceived: c.TotalMSatReceived,
}
// Copy over the current set of HTLCs to ensure the caller can't
// mutate our internal state.
snapshot.Htlcs = make([]HTLC, len(c.Htlcs))
for i, h := range c.Htlcs {
snapshot.Htlcs[i] = h.Copy()
}
return snapshot
}
func putChannelCloseSummary(tx *bolt.Tx, chanID []byte,
summary *ChannelCloseSummary) error {
closedChanBucket, err := tx.CreateBucketIfNotExists(closedChannelBucket)
if err != nil {
return err
}
var b bytes.Buffer
if err := serializeChannelCloseSummary(&b, summary); err != nil {
return err
}
return closedChanBucket.Put(chanID, b.Bytes())
}
func serializeChannelCloseSummary(w io.Writer, cs *ChannelCloseSummary) error {
if err := writeBool(w, cs.IsPending); err != nil {
return err
}
if err := writeOutpoint(w, &cs.ChanPoint); err != nil {
return err
}
if _, err := w.Write(cs.ClosingTXID[:]); err != nil {
return err
}
if err := binary.Write(w, byteOrder, cs.SettledBalance); err != nil {
return err
}
if err := binary.Write(w, byteOrder, cs.TimeLockedBalance); err != nil {
return err
}
if err := binary.Write(w, byteOrder, cs.Capacity); err != nil {
return err
}
if _, err := w.Write([]byte{byte(cs.CloseType)}); err != nil {
return err
}
pub := cs.RemotePub.SerializeCompressed()
if _, err := w.Write(pub); err != nil {
return err
}
return nil
}
func fetchChannelCloseSummary(tx *bolt.Tx,
chanID []byte) (*ChannelCloseSummary, error) {
closedChanBucket, err := tx.CreateBucketIfNotExists(closedChannelBucket)
if err != nil {
return nil, err
}
summaryBytes := closedChanBucket.Get(chanID)
if summaryBytes == nil {
return nil, fmt.Errorf("closed channel summary not found")
}
summaryReader := bytes.NewReader(summaryBytes)
return deserializeCloseChannelSummary(summaryReader)
}
func deserializeCloseChannelSummary(r io.Reader) (*ChannelCloseSummary, error) {
c := &ChannelCloseSummary{}
var err error
c.IsPending, err = readBool(r)
if err != nil {
return nil, err
}
if err := readOutpoint(r, &c.ChanPoint); err != nil {
return nil, err
}
if _, err := io.ReadFull(r, c.ClosingTXID[:]); err != nil {
return nil, err
}
if err := binary.Read(r, byteOrder, &c.SettledBalance); err != nil {
return nil, err
}
if err := binary.Read(r, byteOrder, &c.TimeLockedBalance); err != nil {
return nil, err
}
if err := binary.Read(r, byteOrder, &c.Capacity); err != nil {
return nil, err
}
var closeType [1]byte
if _, err := io.ReadFull(r, closeType[:]); err != nil {
return nil, err
}
c.CloseType = ClosureType(closeType[0])
var pub [33]byte
if _, err := io.ReadFull(r, pub[:]); err != nil {
return nil, err
}
c.RemotePub, err = btcec.ParsePubKey(pub[:], btcec.S256())
if err != nil {
return nil, err
}
return c, nil
}
// putChannel serializes, and stores the current state of the channel in its
// entirety.
func putOpenChannel(openChanBucket *bolt.Bucket, nodeChanBucket *bolt.Bucket,
channel *OpenChannel) error {
// First write out all the "common" fields using the field's prefix
// append with the channel's ID. These fields go into a top-level
// bucket to allow for ease of metric aggregation via efficient prefix
// scans.
if err := putChanCapacity(openChanBucket, channel); err != nil {
return err
}
if err := putChanFeePerKw(openChanBucket, channel); err != nil {
return err
}
if err := putChanNumUpdates(openChanBucket, channel); err != nil {
return err
}
if err := putChanAmountsTransferred(openChanBucket, channel); err != nil {
return err
}
if err := putChanIsPending(openChanBucket, channel); err != nil {
return err
}
if err := putChanConfInfo(openChanBucket, channel); err != nil {
return err
}
if err := putChanCommitFee(openChanBucket, channel); err != nil {
return err
}
// Next, write out the fields of the channel update less frequently.
if err := putChannelIDs(nodeChanBucket, channel); err != nil {
return err
}
if err := putChanConfigs(nodeChanBucket, channel); err != nil {
return err
}
if err := putChanCommitTxns(nodeChanBucket, channel); err != nil {
return err
}
if err := putChanFundingInfo(nodeChanBucket, channel); err != nil {
return err
}
if err := putChanRevocationState(nodeChanBucket, channel); err != nil {
return err
}
if err := putCurrentHtlcs(nodeChanBucket, channel.Htlcs,
&channel.FundingOutpoint); err != nil {
return err
}
return nil
}
// fetchOpenChannel retrieves, and deserializes (including decrypting
// sensitive) the complete channel currently active with the passed nodeID.
func fetchOpenChannel(openChanBucket *bolt.Bucket, nodeChanBucket *bolt.Bucket,
chanID *wire.OutPoint) (*OpenChannel, error) {
var err error
channel := &OpenChannel{
FundingOutpoint: *chanID,
}
// First, read out the fields of the channel update less frequently.
if err = fetchChannelIDs(nodeChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read chan ID's: %v", err)
}
if err = fetchChanConfigs(nodeChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read chan config: %v", err)
}
if err = fetchChanCommitTxns(nodeChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read commit txns: %v", err)
}
if err = fetchChanFundingInfo(nodeChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read funding info: %v", err)
}
if err = fetchChanRevocationState(nodeChanBucket, channel); err != nil {
return nil, err
}
channel.Htlcs, err = fetchCurrentHtlcs(nodeChanBucket, chanID)
if err != nil {
return nil, fmt.Errorf("unable to read current htlc's: %v", err)
}
// With the existence of an open channel bucket with this node verified,
// perform a full read of the entire struct. Starting with the prefixed
// fields residing in the parent bucket.
// TODO(roasbeef): combine the below into channel config like key
if err = fetchChanCapacity(openChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read chan capacity: %v", err)
}
if err = fetchChanMinFeePerKw(openChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read fee-per-kb: %v", err)
}
if err = fetchChanNumUpdates(openChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read num updates: %v", err)
}
if err = fetchChanAmountsTransferred(openChanBucket, channel); err != nil {
return nil, fmt.Errorf("unable to read sat transferred: %v", err)
}
if err = fetchChanIsPending(openChanBucket, channel); err != nil {
return nil, err
}
if err := fetchChanConfInfo(openChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanCommitFee(openChanBucket, channel); err != nil {
return nil, err
}
return channel, nil
}
func deleteOpenChannel(openChanBucket *bolt.Bucket, nodeChanBucket *bolt.Bucket,
channelID []byte, o *wire.OutPoint) error {
// First we'll delete all the "common" top level items stored outside
// the node's channel bucket.
if err := deleteChanCapacity(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanMinFeePerKw(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanNumUpdates(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanAmountsTransferred(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanIsPending(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanConfInfo(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanCommitFee(openChanBucket, channelID); err != nil {
return err
}
// Finally, delete all the fields directly within the node's channel
// bucket.
if err := deleteChannelIDs(nodeChanBucket, channelID); err != nil {
return err
}
if err := deleteChanConfigs(nodeChanBucket, channelID); err != nil {
return err
}
if err := deleteChanCommitTxns(nodeChanBucket, channelID); err != nil {
return err
}
if err := deleteChanFundingInfo(nodeChanBucket, channelID); err != nil {
return err
}
if err := deleteChanRevocationState(nodeChanBucket, channelID); err != nil {
return err
}
if err := deleteCurrentHtlcs(nodeChanBucket, o); err != nil {
return err
}
return nil
}
func putChanCapacity(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
// Some scratch bytes re-used for serializing each of the uint64's.
scratch1 := make([]byte, 8)
scratch2 := make([]byte, 8)
scratch3 := make([]byte, 8)
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], chanCapacityPrefix)
byteOrder.PutUint64(scratch1, uint64(channel.Capacity))
if err := openChanBucket.Put(keyPrefix, scratch1); err != nil {
return err
}
copy(keyPrefix[:3], selfBalancePrefix)
byteOrder.PutUint64(scratch2, uint64(channel.LocalBalance))
if err := openChanBucket.Put(keyPrefix, scratch2); err != nil {
return err
}
copy(keyPrefix[:3], theirBalancePrefix)
byteOrder.PutUint64(scratch3, uint64(channel.RemoteBalance))
return openChanBucket.Put(keyPrefix, scratch3)
}
func deleteChanCapacity(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix[3:], chanID)
copy(keyPrefix[:3], chanCapacityPrefix)
if err := openChanBucket.Delete(keyPrefix); err != nil {
return err
}
copy(keyPrefix[:3], selfBalancePrefix)
if err := openChanBucket.Delete(keyPrefix); err != nil {
return err
}
copy(keyPrefix[:3], theirBalancePrefix)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanCapacity(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
// A byte slice re-used to compute each key prefix below.
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], chanCapacityPrefix)
capacityBytes := openChanBucket.Get(keyPrefix)
channel.Capacity = btcutil.Amount(byteOrder.Uint64(capacityBytes))
copy(keyPrefix[:3], selfBalancePrefix)
selfBalanceBytes := openChanBucket.Get(keyPrefix)
channel.LocalBalance = lnwire.MilliSatoshi(byteOrder.Uint64(selfBalanceBytes))
copy(keyPrefix[:3], theirBalancePrefix)
theirBalanceBytes := openChanBucket.Get(keyPrefix)
channel.RemoteBalance = lnwire.MilliSatoshi(byteOrder.Uint64(theirBalanceBytes))
return nil
}
func putChanFeePerKw(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch := make([]byte, 8)
byteOrder.PutUint64(scratch, uint64(channel.FeePerKw))
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, minFeePerKwPrefix)
copy(keyPrefix[3:], b.Bytes())
return openChanBucket.Put(keyPrefix, scratch)
}
func deleteChanMinFeePerKw(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix, minFeePerKwPrefix)
copy(keyPrefix[3:], chanID)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanMinFeePerKw(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, minFeePerKwPrefix)
copy(keyPrefix[3:], b.Bytes())
feeBytes := openChanBucket.Get(keyPrefix)
channel.FeePerKw = btcutil.Amount(byteOrder.Uint64(feeBytes))
return nil
}
func putChanNumUpdates(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch := make([]byte, 8)
byteOrder.PutUint64(scratch, channel.NumUpdates)
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, updatePrefix)
copy(keyPrefix[3:], b.Bytes())
return openChanBucket.Put(keyPrefix, scratch)
}
func deleteChanNumUpdates(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix, updatePrefix)
copy(keyPrefix[3:], chanID)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanNumUpdates(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, updatePrefix)
copy(keyPrefix[3:], b.Bytes())
updateBytes := openChanBucket.Get(keyPrefix)
channel.NumUpdates = byteOrder.Uint64(updateBytes)
return nil
}
func putChanAmountsTransferred(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch1 := make([]byte, 8)
scratch2 := make([]byte, 8)
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], satSentPrefix)
byteOrder.PutUint64(scratch1, uint64(channel.TotalMSatSent))
if err := openChanBucket.Put(keyPrefix, scratch1); err != nil {
return err
}
copy(keyPrefix[:3], satReceivedPrefix)
byteOrder.PutUint64(scratch2, uint64(channel.TotalMSatReceived))
return openChanBucket.Put(keyPrefix, scratch2)
}
func deleteChanAmountsTransferred(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix[3:], chanID)
copy(keyPrefix[:3], satSentPrefix)
if err := openChanBucket.Delete(keyPrefix); err != nil {
return err
}
copy(keyPrefix[:3], satReceivedPrefix)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanAmountsTransferred(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], satSentPrefix)
totalSentBytes := openChanBucket.Get(keyPrefix)
channel.TotalMSatSent = lnwire.MilliSatoshi(byteOrder.Uint64(totalSentBytes))
copy(keyPrefix[:3], satReceivedPrefix)
totalReceivedBytes := openChanBucket.Get(keyPrefix)
channel.TotalMSatReceived = lnwire.MilliSatoshi(byteOrder.Uint64(totalReceivedBytes))
return nil
}
func putChanIsPending(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch := make([]byte, 2)
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], isPendingPrefix)
if channel.IsPending {
byteOrder.PutUint16(scratch, uint16(1))
return openChanBucket.Put(keyPrefix, scratch)
}
byteOrder.PutUint16(scratch, uint16(0))
return openChanBucket.Put(keyPrefix, scratch)
}
func deleteChanIsPending(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix[3:], chanID)
copy(keyPrefix[:3], isPendingPrefix)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanIsPending(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], isPendingPrefix)
isPending := byteOrder.Uint16(openChanBucket.Get(keyPrefix))
if isPending == 1 {
channel.IsPending = true
} else {
channel.IsPending = false
}
return nil
}
func putChanConfInfo(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, len(confInfoPrefix)+b.Len())
copy(keyPrefix[:len(confInfoPrefix)], confInfoPrefix)
copy(keyPrefix[len(confInfoPrefix):], b.Bytes())
// We store the conf info in the following format: broadcast || open.
var scratch [12]byte
byteOrder.PutUint32(scratch[:], channel.FundingBroadcastHeight)
byteOrder.PutUint64(scratch[4:], channel.ShortChanID.ToUint64())
return openChanBucket.Put(keyPrefix, scratch[:])
}
func fetchChanConfInfo(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, len(confInfoPrefix)+b.Len())
copy(keyPrefix[:len(confInfoPrefix)], confInfoPrefix)
copy(keyPrefix[len(confInfoPrefix):], b.Bytes())
confInfoBytes := openChanBucket.Get(keyPrefix)
channel.FundingBroadcastHeight = byteOrder.Uint32(confInfoBytes[:4])
channel.ShortChanID = lnwire.NewShortChanIDFromInt(
byteOrder.Uint64(confInfoBytes[4:]),
)
return nil
}
func deleteChanConfInfo(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, len(confInfoPrefix)+len(chanID))
copy(keyPrefix[:len(confInfoPrefix)], confInfoPrefix)
copy(keyPrefix[len(confInfoPrefix):], chanID)
return openChanBucket.Delete(keyPrefix)
}
func putChannelIDs(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
// TODO(roasbeef): just pass in chanID everywhere for puts
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
// Construct the id key: cid || channelID.
// TODO(roasbeef): abstract out to func
idKey := make([]byte, len(chanIDKey)+b.Len())
copy(idKey[:3], chanIDKey)
copy(idKey[3:], b.Bytes())
idBytes := channel.IdentityPub.SerializeCompressed()
return nodeChanBucket.Put(idKey, idBytes)
}
func deleteChannelIDs(nodeChanBucket *bolt.Bucket, chanID []byte) error {
idKey := make([]byte, len(chanIDKey)+len(chanID))
copy(idKey[:3], chanIDKey)
copy(idKey[3:], chanID)
return nodeChanBucket.Delete(idKey)
}
func fetchChannelIDs(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var (
err error
b bytes.Buffer
)
if err = writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
// Construct the id key: cid || channelID.
idKey := make([]byte, len(chanIDKey)+b.Len())
copy(idKey[:3], chanIDKey)
copy(idKey[3:], b.Bytes())
idBytes := nodeChanBucket.Get(idKey)
channel.IdentityPub, err = btcec.ParsePubKey(idBytes, btcec.S256())
if err != nil {
return err
}
return nil
}
func putChanCommitFee(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch := make([]byte, 8)
byteOrder.PutUint64(scratch, uint64(channel.CommitFee))
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, commitFeePrefix)
copy(keyPrefix[3:], b.Bytes())
return openChanBucket.Put(keyPrefix, scratch)
}
func fetchChanCommitFee(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, commitFeePrefix)
copy(keyPrefix[3:], b.Bytes())
commitFeeBytes := openChanBucket.Get(keyPrefix)
channel.CommitFee = btcutil.Amount(byteOrder.Uint64(commitFeeBytes))
return nil
}
func deleteChanCommitFee(openChanBucket *bolt.Bucket, chanID []byte) error {
commitFeeKey := make([]byte, 3+len(chanID))
copy(commitFeeKey, commitFeePrefix)
copy(commitFeeKey[3:], chanID)
return openChanBucket.Delete(commitFeeKey)
}
func putChanCommitTxns(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, &channel.FundingOutpoint); err != nil {
return err
}
txnsKey := make([]byte, len(commitTxnsKey)+bc.Len())
copy(txnsKey[:3], commitTxnsKey)
copy(txnsKey[3:], bc.Bytes())
var b bytes.Buffer
if err := channel.CommitTx.Serialize(&b); err != nil {
return err
}
if err := wire.WriteVarBytes(&b, 0, channel.CommitSig); err != nil {
return err
}
return nodeChanBucket.Put(txnsKey, b.Bytes())
}
func deleteChanCommitTxns(nodeChanBucket *bolt.Bucket, chanID []byte) error {
txnsKey := make([]byte, len(commitTxnsKey)+len(chanID))
copy(txnsKey[:3], commitTxnsKey)
copy(txnsKey[3:], chanID)
return nodeChanBucket.Delete(txnsKey)
}
func fetchChanCommitTxns(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
var err error
if err = writeOutpoint(&bc, &channel.FundingOutpoint); err != nil {
return err
}
txnsKey := make([]byte, len(commitTxnsKey)+bc.Len())
copy(txnsKey[:3], commitTxnsKey)
copy(txnsKey[3:], bc.Bytes())
txnBytes := bytes.NewReader(nodeChanBucket.Get(txnsKey))
channel.CommitTx = *wire.NewMsgTx(2)
if err = channel.CommitTx.Deserialize(txnBytes); err != nil {
return err
}
channel.CommitSig, err = wire.ReadVarBytes(txnBytes, 0, 80, "")
if err != nil {
return err
}
return nil
}
func putChanConfigs(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
putChanConfig := func(cfg *ChannelConfig) error {
err := binary.Write(&b, byteOrder, cfg.DustLimit)
if err != nil {
return err
}
err = binary.Write(&b, byteOrder, cfg.MaxPendingAmount)
if err != nil {
return err
}
err = binary.Write(&b, byteOrder, cfg.ChanReserve)
if err != nil {
return err
}
err = binary.Write(&b, byteOrder, cfg.MinHTLC)
if err != nil {
return err
}
err = binary.Write(&b, byteOrder, cfg.CsvDelay)
if err != nil {
return err
}
err = binary.Write(&b, byteOrder, cfg.MaxAcceptedHtlcs)
if err != nil {
return err
}
_, err = b.Write(cfg.MultiSigKey.SerializeCompressed())
if err != nil {
return err
}
_, err = b.Write(cfg.RevocationBasePoint.SerializeCompressed())
if err != nil {
return err
}
_, err = b.Write(cfg.PaymentBasePoint.SerializeCompressed())
if err != nil {
return err
}
_, err = b.Write(cfg.DelayBasePoint.SerializeCompressed())
if err != nil {
return err
}
return nil
}
putChanConfig(&channel.LocalChanCfg)
putChanConfig(&channel.RemoteChanCfg)
var bc bytes.Buffer
if err := writeOutpoint(&bc, &channel.FundingOutpoint); err != nil {
return err
}
configKey := make([]byte, len(chanConfigPrefix)+len(bc.Bytes()))
copy(configKey, chanConfigPrefix)
copy(configKey, bc.Bytes())
return nodeChanBucket.Put(configKey, b.Bytes())
}
func fetchChanConfigs(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, &channel.FundingOutpoint); err != nil {
return err
}
configKey := make([]byte, len(chanConfigPrefix)+len(bc.Bytes()))
copy(configKey, chanConfigPrefix)
copy(configKey, bc.Bytes())
configBytes := nodeChanBucket.Get(configKey)
if configBytes == nil {
return fmt.Errorf("unable to find channel config for %v: ",
channel.FundingOutpoint)
}
configReader := bytes.NewReader(configBytes)
fetchChanConfig := func() (*ChannelConfig, error) {
cfg := &ChannelConfig{}
err := binary.Read(configReader, byteOrder, &cfg.DustLimit)
if err != nil {
return nil, err
}
err = binary.Read(configReader, byteOrder, &cfg.MaxPendingAmount)
if err != nil {
return nil, err
}
err = binary.Read(configReader, byteOrder, &cfg.ChanReserve)
if err != nil {
return nil, err
}
err = binary.Read(configReader, byteOrder, &cfg.MinHTLC)
if err != nil {
return nil, err
}
err = binary.Read(configReader, byteOrder, &cfg.CsvDelay)
if err != nil {
return nil, err
}
err = binary.Read(configReader, byteOrder, &cfg.MaxAcceptedHtlcs)
if err != nil {
return nil, err
}
var pub [33]byte
readKey := func() (*btcec.PublicKey, error) {
if _, err := io.ReadFull(configReader, pub[:]); err != nil {
return nil, err
}
return btcec.ParsePubKey(pub[:], btcec.S256())
}
cfg.MultiSigKey, err = readKey()
if err != nil {
return nil, err
}
cfg.RevocationBasePoint, err = readKey()
if err != nil {
return nil, err
}
cfg.PaymentBasePoint, err = readKey()
if err != nil {
return nil, err
}
cfg.DelayBasePoint, err = readKey()
if err != nil {
return nil, err
}
return cfg, nil
}
var err error
cfg, err := fetchChanConfig()
if err != nil {
return err
}
channel.LocalChanCfg = *cfg
cfg, err = fetchChanConfig()
if err != nil {
return err
}
channel.RemoteChanCfg = *cfg
return nil
}
func deleteChanConfigs(nodeChanBucket *bolt.Bucket, chanID []byte) error {
configKey := make([]byte, len(chanConfigPrefix)+len(chanID))
copy(configKey, chanConfigPrefix)
copy(configKey, chanID)
return nodeChanBucket.Delete(configKey)
}
func putChanFundingInfo(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, &channel.FundingOutpoint); err != nil {
return err
}
fundTxnKey := make([]byte, len(fundingTxnKey)+bc.Len())
copy(fundTxnKey[:3], fundingTxnKey)
copy(fundTxnKey[3:], bc.Bytes())
var b bytes.Buffer
var boolByte [1]byte
if channel.IsInitiator {
boolByte[0] = 1
} else {
boolByte[0] = 0
}
if _, err := b.Write(boolByte[:]); err != nil {
return err
}
// TODO(roasbeef): make first field instead?
if _, err := b.Write([]byte{uint8(channel.ChanType)}); err != nil {
return err
}
if _, err := b.Write(channel.ChainHash[:]); err != nil {
return err
}
var scratch [2]byte
byteOrder.PutUint16(scratch[:], channel.NumConfsRequired)
if _, err := b.Write(scratch[:]); err != nil {
return err
}
return nodeChanBucket.Put(fundTxnKey, b.Bytes())
}
func deleteChanFundingInfo(nodeChanBucket *bolt.Bucket, chanID []byte) error {
fundTxnKey := make([]byte, len(fundingTxnKey)+len(chanID))
copy(fundTxnKey[:3], fundingTxnKey)
copy(fundTxnKey[3:], chanID)
return nodeChanBucket.Delete(fundTxnKey)
}
func fetchChanFundingInfo(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
fundTxnKey := make([]byte, len(fundingTxnKey)+b.Len())
copy(fundTxnKey[:3], fundingTxnKey)
copy(fundTxnKey[3:], b.Bytes())
infoBytes := bytes.NewReader(nodeChanBucket.Get(fundTxnKey))
var boolByte [1]byte
if _, err := io.ReadFull(infoBytes, boolByte[:]); err != nil {
return err
}
if boolByte[0] == 1 {
channel.IsInitiator = true
} else {
channel.IsInitiator = false
}
var chanType [1]byte
if _, err := io.ReadFull(infoBytes, chanType[:]); err != nil {
return err
}
channel.ChanType = ChannelType(chanType[0])
if _, err := io.ReadFull(infoBytes, channel.ChainHash[:]); err != nil {
return err
}
var scratch [2]byte
if _, err := infoBytes.Read(scratch[:]); err != nil {
return err
}
channel.NumConfsRequired = byteOrder.Uint16(scratch[:])
return nil
}
func putChanRevocationState(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
curRevKey := channel.RemoteCurrentRevocation.SerializeCompressed()
if err := wire.WriteVarBytes(&b, 0, curRevKey); err != nil {
return err
}
// TODO(roasbeef): shouldn't be storing on disk, should re-derive as
// needed
if err := channel.RevocationProducer.Encode(&b); err != nil {
return err
}
if err := channel.RevocationStore.Encode(&b); err != nil {
return err
}
var bc bytes.Buffer
if err := writeOutpoint(&bc, &channel.FundingOutpoint); err != nil {
return err
}
// We place the next revocation key at the very end, as under certain
// circumstances (when a channel is initially funded), this value will
// not yet have been set.
//
// TODO(roasbeef): segment the storage?
if channel.RemoteNextRevocation != nil {
nextRevKey := channel.RemoteNextRevocation.SerializeCompressed()
if err := wire.WriteVarBytes(&b, 0, nextRevKey); err != nil {
return err
}
}
revocationKey := make([]byte, len(revocationStateKey)+bc.Len())
copy(revocationKey[:3], revocationStateKey)
copy(revocationKey[3:], bc.Bytes())
return nodeChanBucket.Put(revocationKey, b.Bytes())
}
func deleteChanRevocationState(nodeChanBucket *bolt.Bucket, chanID []byte) error {
revocationKey := make([]byte, len(revocationStateKey)+len(chanID))
copy(revocationKey[:3], revocationStateKey)
copy(revocationKey[3:], chanID)
return nodeChanBucket.Delete(revocationKey)
}
func fetchChanRevocationState(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, &channel.FundingOutpoint); err != nil {
return err
}
preimageKey := make([]byte, len(revocationStateKey)+b.Len())
copy(preimageKey[:3], revocationStateKey)
copy(preimageKey[3:], b.Bytes())
reader := bytes.NewReader(nodeChanBucket.Get(preimageKey))
curRevKeyBytes, err := wire.ReadVarBytes(reader, 0, 1000, "")
if err != nil {
return err
}
channel.RemoteCurrentRevocation, err = btcec.ParsePubKey(curRevKeyBytes, btcec.S256())
if err != nil {
return err
}
// TODO(roasbeef): should be rederiving on fly, or encrypting on disk.
var root [32]byte
if _, err := io.ReadFull(reader, root[:]); err != nil {
return err
}
channel.RevocationProducer, err = shachain.NewRevocationProducerFromBytes(root[:])
if err != nil {
return err
}
channel.RevocationStore, err = shachain.NewRevocationStoreFromBytes(reader)
if err != nil {
return err
}
// We'll attempt to see if the remote party's next revocation key is
// currently set, if so then we'll read and deserialize it. Otherwise,
// we can exit early.
if reader.Len() != 0 {
nextRevKeyBytes, err := wire.ReadVarBytes(reader, 0, 1000, "")
if err != nil {
return err
}
channel.RemoteNextRevocation, err = btcec.ParsePubKey(
nextRevKeyBytes, btcec.S256(),
)
if err != nil {
return err
}
}
return nil
}
func serializeHTLC(w io.Writer, h *HTLC) error {
if err := wire.WriteVarBytes(w, 0, h.Signature); err != nil {
return err
}
if _, err := w.Write(h.RHash[:]); err != nil {
return err
}
if err := binary.Write(w, byteOrder, h.Amt); err != nil {
return err
}
if err := binary.Write(w, byteOrder, h.RefundTimeout); err != nil {
return err
}
if err := binary.Write(w, byteOrder, h.OutputIndex); err != nil {
return err
}
var boolByte [1]byte
if h.Incoming {
boolByte[0] = 1
} else {
boolByte[0] = 0
}
if _, err := w.Write(boolByte[:]); err != nil {
return err
}
return nil
}
func deserializeHTLC(r io.Reader) (*HTLC, error) {
h := &HTLC{}
sigBytes, err := wire.ReadVarBytes(r, 0, 80, "")
if err != nil {
return nil, err
}
h.Signature = sigBytes
if _, err := io.ReadFull(r, h.RHash[:]); err != nil {
return nil, err
}
if err := binary.Read(r, byteOrder, &h.Amt); err != nil {
return nil, err
}
if err := binary.Read(r, byteOrder, &h.RefundTimeout); err != nil {
return nil, err
}
if err := binary.Read(r, byteOrder, &h.OutputIndex); err != nil {
return nil, err
}
var scratch [1]byte
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
if scratch[0] == 1 {
h.Incoming = true
} else {
h.Incoming = false
}
return h, nil
}
func makeHtlcKey(o *wire.OutPoint) [39]byte {
var (
n int
k [39]byte
)
// chk || txid || index
n += copy(k[:], currentHtlcKey)
n += copy(k[n:], o.Hash[:])
var scratch [4]byte
byteOrder.PutUint32(scratch[:], o.Index)
copy(k[n:], scratch[:])
return k
}
func putCurrentHtlcs(nodeChanBucket *bolt.Bucket, htlcs []*HTLC,
o *wire.OutPoint) error {
var b bytes.Buffer
for _, htlc := range htlcs {
if err := serializeHTLC(&b, htlc); err != nil {
return err
}
}
htlcKey := makeHtlcKey(o)
return nodeChanBucket.Put(htlcKey[:], b.Bytes())
}
func fetchCurrentHtlcs(nodeChanBucket *bolt.Bucket,
o *wire.OutPoint) ([]*HTLC, error) {
htlcKey := makeHtlcKey(o)
htlcBytes := nodeChanBucket.Get(htlcKey[:])
if htlcBytes == nil {
return nil, nil
}
// TODO(roasbeef): can preallocate here
var htlcs []*HTLC
htlcReader := bytes.NewReader(htlcBytes)
for htlcReader.Len() != 0 {
htlc, err := deserializeHTLC(htlcReader)
if err != nil {
return nil, err
}
htlcs = append(htlcs, htlc)
}
return htlcs, nil
}
func deleteCurrentHtlcs(nodeChanBucket *bolt.Bucket, o *wire.OutPoint) error {
htlcKey := makeHtlcKey(o)
return nodeChanBucket.Delete(htlcKey[:])
}
func serializeChannelDelta(w io.Writer, delta *ChannelDelta) error {
// TODO(roasbeef): could use compression here to reduce on-disk space.
var scratch [8]byte
byteOrder.PutUint64(scratch[:], uint64(delta.LocalBalance))
if _, err := w.Write(scratch[:]); err != nil {
return err
}
byteOrder.PutUint64(scratch[:], uint64(delta.RemoteBalance))
if _, err := w.Write(scratch[:]); err != nil {
return err
}
byteOrder.PutUint64(scratch[:], delta.UpdateNum)
if _, err := w.Write(scratch[:]); err != nil {
return err
}
numHtlcs := uint64(len(delta.Htlcs))
if err := wire.WriteVarInt(w, 0, numHtlcs); err != nil {
return err
}
for _, htlc := range delta.Htlcs {
if err := serializeHTLC(w, htlc); err != nil {
return err
}
}
byteOrder.PutUint64(scratch[:], uint64(delta.CommitFee))
if _, err := w.Write(scratch[:]); err != nil {
return err
}
byteOrder.PutUint64(scratch[:], uint64(delta.FeePerKw))
if _, err := w.Write(scratch[:]); err != nil {
return err
}
return nil
}
func deserializeChannelDelta(r io.Reader) (*ChannelDelta, error) {
var (
err error
scratch [8]byte
)
delta := &ChannelDelta{}
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
delta.LocalBalance = lnwire.MilliSatoshi(byteOrder.Uint64(scratch[:]))
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
delta.RemoteBalance = lnwire.MilliSatoshi(byteOrder.Uint64(scratch[:]))
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
delta.UpdateNum = byteOrder.Uint64(scratch[:])
numHtlcs, err := wire.ReadVarInt(r, 0)
if err != nil {
return nil, err
}
delta.Htlcs = make([]*HTLC, numHtlcs)
for i := uint64(0); i < numHtlcs; i++ {
htlc, err := deserializeHTLC(r)
if err != nil {
return nil, err
}
delta.Htlcs[i] = htlc
}
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
delta.CommitFee = btcutil.Amount(byteOrder.Uint64(scratch[:]))
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
delta.FeePerKw = btcutil.Amount(byteOrder.Uint64(scratch[:]))
return delta, nil
}
func makeLogKey(o *wire.OutPoint, updateNum uint64) [44]byte {
var (
scratch [8]byte
n int
// txid (32) || index (4) || update_num (8)
// 32 + 4 + 8 = 44
k [44]byte
)
n += copy(k[:], o.Hash[:])
byteOrder.PutUint32(scratch[:4], o.Index)
n += copy(k[n:], scratch[:4])
byteOrder.PutUint64(scratch[:], updateNum)
copy(k[n:], scratch[:])
return k
}
func appendChannelLogEntry(log *bolt.Bucket, delta *ChannelDelta,
chanPoint *wire.OutPoint) error {
var b bytes.Buffer
if err := serializeChannelDelta(&b, delta); err != nil {
return err
}
logEntrykey := makeLogKey(chanPoint, delta.UpdateNum)
return log.Put(logEntrykey[:], b.Bytes())
}
func fetchChannelLogEntry(log *bolt.Bucket, chanPoint *wire.OutPoint,
updateNum uint64) (*ChannelDelta, error) {
logEntrykey := makeLogKey(chanPoint, updateNum)
deltaBytes := log.Get(logEntrykey[:])
if deltaBytes == nil {
return nil, fmt.Errorf("log entry not found")
}
deltaReader := bytes.NewReader(deltaBytes)
return deserializeChannelDelta(deltaReader)
}
func wipeChannelLogEntries(log *bolt.Bucket, o *wire.OutPoint) error {
var (
n int
logPrefix [32 + 4]byte
scratch [4]byte
)
// First we'll construct a key prefix that we'll use to scan through
// and delete all the log entries related to this channel. The format
// for log entries within the database is: txid || index || update_num.
// We'll construct a prefix key with the first two thirds of the full
// key to scan with and delete all entries.
n += copy(logPrefix[:], o.Hash[:])
byteOrder.PutUint32(scratch[:], o.Index)
copy(logPrefix[n:], scratch[:])
// With the prefix constructed, scan through the log bucket from the
// starting point of the log entries for this channel. We'll keep
// deleting keys until the prefix no longer matches.
logCursor := log.Cursor()
for logKey, _ := logCursor.Seek(logPrefix[:]); bytes.HasPrefix(logKey, logPrefix[:]); logKey, _ = logCursor.Next() {
if err := log.Delete(logKey); err != nil {
return err
}
}
return nil
}
func writeOutpoint(w io.Writer, o *wire.OutPoint) error {
// TODO(roasbeef): make all scratch buffers on the stack
scratch := make([]byte, 4)
// TODO(roasbeef): write raw 32 bytes instead of wasting the extra
// byte.
if err := wire.WriteVarBytes(w, 0, o.Hash[:]); err != nil {
return err
}
byteOrder.PutUint32(scratch, o.Index)
_, err := w.Write(scratch)
return err
}
func readOutpoint(r io.Reader, o *wire.OutPoint) error {
scratch := make([]byte, 4)
txid, err := wire.ReadVarBytes(r, 0, 32, "prevout")
if err != nil {
return err
}
copy(o.Hash[:], txid)
if _, err := r.Read(scratch); err != nil {
return err
}
o.Index = byteOrder.Uint32(scratch)
return nil
}
func writeBool(w io.Writer, b bool) error {
boolByte := byte(0x01)
if !b {
boolByte = byte(0x00)
}
if _, err := w.Write([]byte{boolByte}); err != nil {
return err
}
return nil
}
// TODO(roasbeef): make sweep to use this and above everywhere
// * using this because binary.Write can only handle bools post go1.8
func readBool(r io.Reader) (bool, error) {
var boolByte [1]byte
if _, err := io.ReadFull(r, boolByte[:]); err != nil {
return false, err
}
if boolByte[0] == 0x00 {
return false, nil
}
return true, nil
}
// TODO(roasbeef): add readElement/writeElement funcs
// * after go1.9 can use binary.WriteBool etc?