lnd.xprv/channeldb/channel.go
Olaoluwa Osuntokun 3354685292
channeldb: add FullSyncWithAddr method to OpenChannel
This commit adds a new method ‘FullSyncWithAddr’ which is identical to
the existing ‘FullSync’ method other than it also creates an
association from the channel to a LinkNode object within the database.

This new method is required in order to create persistent links between
channels and link nodes which will later allow the development of
heuristics which decided when it “makes sense” to close a channel due
to inactivity. Additionally, this new association will allow for a
sub-system within the daemon to attempt to establish persistent
connections out to all LinkNodes in order to strive for channel
availability.
2016-10-26 14:47:10 -07:00

1643 lines
46 KiB
Go

package channeldb
import (
"bytes"
"fmt"
"io"
"net"
"sync"
"time"
"github.com/boltdb/bolt"
"github.com/lightningnetwork/lnd/elkrem"
"github.com/roasbeef/btcd/btcec"
"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 meta-data 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 orer to facilitate sequential prefix scans
// to gather stats such as total satoshis received.
openChannelBucket = []byte("ocb")
// chanIDBucket is a thrid-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 counter party 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")
minFeePerKbPrefix = []byte("mfp")
updatePrefix = []byte("uup")
satSentPrefix = []byte("ssp")
satRecievedPrefix = []byte("srp")
netFeesPrefix = []byte("ntp")
// 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 HTLC's on our
// latest commitment state.
currentHtlcKey = []byte("chk")
// fundingTxnKey stroes the funding tx, our encrypted multi-sig key,
// and finally 2-of-2 multisig redeem script.
fundingTxnKey = []byte("fsk")
// elkremStateKey stores their current revocation hash, and our elkrem
// sender, and their elkrem reciever.
elkremStateKey = []byte("esk")
// deliveryScriptsKey stores the scripts for the final delivery in the
// case of a cooperative closure.
deliveryScriptsKey = []byte("dsk")
)
// 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 {
// IdentityPub is the identity public key of the remote node this
// channel has been established with.
IdentityPub *btcec.PublicKey
// The ID of a channel is the txid of the funding transaction.
ChanID *wire.OutPoint
MinFeePerKb btcutil.Amount
// Keys for both sides to be used for the commitment transactions.
OurCommitKey *btcec.PublicKey
TheirCommitKey *btcec.PublicKey
// Tracking total channel capacity, and the amount of funds allocated
// to each side.
Capacity btcutil.Amount
OurBalance btcutil.Amount
TheirBalance btcutil.Amount
// Our current commitment transaction along with their signature for
// our commitment transaction.
OurCommitTx *wire.MsgTx
OurCommitSig []byte
// The outpoint of the final funding transaction.
FundingOutpoint *wire.OutPoint
OurMultiSigKey *btcec.PublicKey
TheirMultiSigKey *btcec.PublicKey
FundingWitnessScript []byte
// In blocks
LocalCsvDelay uint32
RemoteCsvDelay uint32
// Current revocation for their commitment transaction. However, since
// this the derived public key, we don't yet have the pre-image so we
// aren't yet able to verify that it's actually in the hash chain.
TheirCurrentRevocation *btcec.PublicKey
TheirCurrentRevocationHash [32]byte
LocalElkrem *elkrem.ElkremSender
RemoteElkrem *elkrem.ElkremReceiver
// The pkScript for both sides to be used for final delivery in the case
// of a cooperative close.
OurDeliveryScript []byte
TheirDeliveryScript []byte
NumUpdates uint64
TotalSatoshisSent uint64
TotalSatoshisReceived uint64
TotalNetFees uint64 // TODO(roasbeef): total fees paid too?
CreationTime time.Time // TODO(roasbeef): last update time?
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.store.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.
chanIDBucket, err := nodeChanBucket.CreateBucketIfNotExists(chanIDBucket)
if err != nil {
return err
}
var b bytes.Buffer
if err := writeOutpoint(&b, c.ChanID); err != nil {
return err
}
if chanIDBucket.Get(b.Bytes()) == nil {
if err := chanIDBucket.Put(b.Bytes(), nil); err != nil {
return err
}
}
return putOpenChannel(chanBucket, nodeChanBucket, c)
}
// FullSyncWithAddr is identical to the FullSync function in that it writes the
// full channel state to disk. Additionally, this function also creates a
// LinkNode relationship between this newly created channel and an existing of
// new LinkNode instance. Syncing with this method rather than FullSync is
// required in order to allow 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) FullSyncWithAddr(addr *net.TCPAddr) error {
c.Lock()
defer c.Unlock()
return c.Db.store.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 exsits, 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 meta-data contains
// reachability, up-time, and service bits related information.
// TODO(roasbeef): net info shuld 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.store.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.OurCommitTx = newCommitment
c.OurCommitSig = newSig
c.OurBalance = delta.LocalBalance
c.TheirBalance = delta.RemoteBalance
c.NumUpdates = uint64(delta.UpdateNum)
c.Htlcs = delta.Htlcs
// 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 := putChanNumUpdates(chanBucket, c); err != nil {
return err
}
if err := putChanCommitTxns(nodeChanBucket, c); err != nil {
return err
}
if err := putCurrentHtlcs(nodeChanBucket, delta.Htlcs, c.ChanID); err != nil {
return err
}
return nil
})
}
// HTLC is the on-disk representation of a hash time-locked contract. HTLC's
// are contained within ChannelDeltas which encode the current state of the
// commitment between state updates.
type HTLC struct {
// Incoming denotes whether we're the receiver or the sender of this
// HTLC.
Incoming bool
// Amt is the amount of satoshis this HTLC escrows.
Amt btcutil.Amount
// RHash is the payment hash of the HTLC.
RHash [32]byte
// RefundTimeout is the absolute timeout on the HTLC that the sender
// must wait before reclaiming the funds in limbo.
RefundTimeout uint32
// RevocationDelay is the relative timeout the party who broadcasts
// the commitment transaction must wait before being able to fully
// sweep the funds on-chain in the case of a unilateral channel
// closure.
RevocationDelay uint32
// TODO(roasbeef): add output index?
}
// 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,
RevocationDelay: h.RevocationDelay,
}
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 HTLC's are recorded.
type ChannelDelta struct {
LocalBalance btcutil.Amount
RemoteBalance btcutil.Amount
UpdateNum uint32
Htlcs []*HTLC
}
// 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.store.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 elkrem state to disk as the remote peer
// has just added to our local elkrem receiver, and given us a
// new pending revocation key.
if err := putChanElkremState(nodeChanBucket, c); err != nil {
return err
}
// With the current elkrem 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.ChanID)
})
}
// 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.store.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 nodeChanBucket == nil {
return ErrNoPastDeltas
}
var err error
delta, err = fetchChannelLogEntry(logBucket, c.ChanID,
uint32(updateNum))
return err
})
if err != nil {
return nil, err
}
return delta, nil
}
// CloseChannel closes a previously active lightning channel. Closing a channel
// entails deleting all saved state within the database concerning this
// channel, as well as created a small channel summary for record keeping
// purposes.
// TODO(roasbeef): delete on-disk set of HTLC's
func (c *OpenChannel) CloseChannel() error {
return c.Db.store.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.ChanID); err != nil {
return err
}
outPointBytes := b.Bytes()
if err := chanIndexBucket.Delete(b.Bytes()); err != nil {
return err
}
// Now that the index to this channel has been deleted, purge
// the remaining channel meta-data from the database.
if err := deleteOpenChannel(chanBucket, nodeChanBucket,
outPointBytes); err != nil {
return err
}
// Finally, create a summary of this channel in the closed
// channel bucket for this node.
return putClosedChannelSummary(tx, outPointBytes)
})
}
// 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 btcec.PublicKey
ChannelPoint *wire.OutPoint
Capacity btcutil.Amount
LocalBalance btcutil.Amount
RemoteBalance btcutil.Amount
NumUpdates uint64
TotalSatoshisSent uint64
TotalSatoshisReceived uint64
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, meta-data detailing total flows, and any outstanding HTLCs.
func (c *OpenChannel) Snapshot() *ChannelSnapshot {
c.RLock()
defer c.RUnlock()
snapshot := &ChannelSnapshot{
RemoteIdentity: *c.IdentityPub,
ChannelPoint: c.ChanID,
Capacity: c.Capacity,
LocalBalance: c.OurBalance,
RemoteBalance: c.TheirBalance,
NumUpdates: c.NumUpdates,
TotalSatoshisSent: c.TotalSatoshisSent,
TotalSatoshisReceived: c.TotalSatoshisReceived,
}
// Copy over the current set of HTLC's 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 putClosedChannelSummary(tx *bolt.Tx, chanID []byte) error {
// For now, a summary of a closed channel simply involves recording the
// outpoint of the funding transaction.
closedChanBucket, err := tx.CreateBucketIfNotExists(closedChannelBucket)
if err != nil {
return err
}
// TODO(roasbeef): add other info
// * should likely have each in own bucket per node
return closedChanBucket.Put(chanID, 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
// appened 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 := putChanMinFeePerKb(openChanBucket, channel); err != nil {
return err
}
if err := putChanNumUpdates(openChanBucket, channel); err != nil {
return err
}
if err := putChanTotalFlow(openChanBucket, channel); err != nil {
return err
}
if err := putChanNetFee(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 := putChanCommitKeys(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 := putChanElkremState(nodeChanBucket, channel); err != nil {
return err
}
if err := putChanDeliveryScripts(nodeChanBucket, channel); err != nil {
return err
}
if err := putCurrentHtlcs(nodeChanBucket, channel.Htlcs,
channel.ChanID); err != nil {
return err
}
return nil
}
// fetchOpenChannel retrieves, and deserializes (including decrypting
// sensitive) the complete channel currently active with the passed nodeID.
// An EncryptorDecryptor is required to decrypt sensitive information stored
// within the database.
func fetchOpenChannel(openChanBucket *bolt.Bucket, nodeChanBucket *bolt.Bucket,
chanID *wire.OutPoint) (*OpenChannel, error) {
var err error
channel := &OpenChannel{
ChanID: chanID,
}
// First, read out the fields of the channel update less frequently.
if err = fetchChannelIDs(nodeChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanCommitKeys(nodeChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanCommitTxns(nodeChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanFundingInfo(nodeChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanElkremState(nodeChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanDeliveryScripts(nodeChanBucket, channel); err != nil {
return nil, err
}
channel.Htlcs, err = fetchCurrentHtlcs(nodeChanBucket, chanID)
if err != nil {
return nil, 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.
if err = fetchChanCapacity(openChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanMinFeePerKb(openChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanNumUpdates(openChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanTotalFlow(openChanBucket, channel); err != nil {
return nil, err
}
if err = fetchChanNetFee(openChanBucket, channel); err != nil {
return nil, err
}
return channel, nil
}
func deleteOpenChannel(openChanBucket *bolt.Bucket, nodeChanBucket *bolt.Bucket,
channelID []byte) 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 := deleteChanMinFeePerKb(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanNumUpdates(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanTotalFlow(openChanBucket, channelID); err != nil {
return err
}
if err := deleteChanNetFee(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 := deleteChanCommitKeys(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 := deleteChanElkremState(nodeChanBucket, channelID); err != nil {
return err
}
if err := deleteChanDeliveryScripts(nodeChanBucket, channelID); 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.ChanID); 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.OurBalance))
if err := openChanBucket.Put(keyPrefix, scratch2); err != nil {
return err
}
copy(keyPrefix[:3], theirBalancePrefix)
byteOrder.PutUint64(scratch3, uint64(channel.TheirBalance))
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.ChanID); 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.OurBalance = btcutil.Amount(byteOrder.Uint64(selfBalanceBytes))
copy(keyPrefix[:3], theirBalancePrefix)
theirBalanceBytes := openChanBucket.Get(keyPrefix)
channel.TheirBalance = btcutil.Amount(byteOrder.Uint64(theirBalanceBytes))
return nil
}
func putChanMinFeePerKb(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch := make([]byte, 8)
byteOrder.PutUint64(scratch, uint64(channel.MinFeePerKb))
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, minFeePerKbPrefix)
copy(keyPrefix[3:], b.Bytes())
return openChanBucket.Put(keyPrefix, scratch)
}
func deleteChanMinFeePerKb(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix, minFeePerKbPrefix)
copy(keyPrefix[3:], chanID)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanMinFeePerKb(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, minFeePerKbPrefix)
copy(keyPrefix[3:], b.Bytes())
feeBytes := openChanBucket.Get(keyPrefix)
channel.MinFeePerKb = 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.ChanID); 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.ChanID); 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 putChanTotalFlow(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch1 := make([]byte, 8)
scratch2 := make([]byte, 8)
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], satSentPrefix)
byteOrder.PutUint64(scratch1, uint64(channel.TotalSatoshisSent))
if err := openChanBucket.Put(keyPrefix, scratch1); err != nil {
return err
}
copy(keyPrefix[:3], satRecievedPrefix)
byteOrder.PutUint64(scratch2, uint64(channel.TotalSatoshisReceived))
return openChanBucket.Put(keyPrefix, scratch2)
}
func deleteChanTotalFlow(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], satRecievedPrefix)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanTotalFlow(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix[3:], b.Bytes())
copy(keyPrefix[:3], satSentPrefix)
totalSentBytes := openChanBucket.Get(keyPrefix)
channel.TotalSatoshisSent = byteOrder.Uint64(totalSentBytes)
copy(keyPrefix[:3], satRecievedPrefix)
totalReceivedBytes := openChanBucket.Get(keyPrefix)
channel.TotalSatoshisReceived = byteOrder.Uint64(totalReceivedBytes)
return nil
}
func putChanNetFee(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
scratch := make([]byte, 8)
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, netFeesPrefix)
copy(keyPrefix[3:], b.Bytes())
byteOrder.PutUint64(scratch, uint64(channel.TotalNetFees))
return openChanBucket.Put(keyPrefix, scratch)
}
func deleteChanNetFee(openChanBucket *bolt.Bucket, chanID []byte) error {
keyPrefix := make([]byte, 3+len(chanID))
copy(keyPrefix, netFeesPrefix)
copy(keyPrefix[3:], chanID)
return openChanBucket.Delete(keyPrefix)
}
func fetchChanNetFee(openChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
keyPrefix := make([]byte, 3+b.Len())
copy(keyPrefix, netFeesPrefix)
copy(keyPrefix[3:], b.Bytes())
feeBytes := openChanBucket.Get(keyPrefix)
channel.TotalNetFees = byteOrder.Uint64(feeBytes)
return nil
}
func putChannelIDs(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
// TODO(roabeef): just pass in chanID everywhere for puts
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); 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.ChanID); 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 putChanCommitKeys(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
// Construct the key which stores the commitment keys: ckk || channelID.
// TODO(roasbeef): factor into func
var bc bytes.Buffer
if err := writeOutpoint(&bc, channel.ChanID); err != nil {
return err
}
commitKey := make([]byte, len(commitKeys)+bc.Len())
copy(commitKey[:3], commitKeys)
copy(commitKey[3:], bc.Bytes())
var b bytes.Buffer
if _, err := b.Write(channel.TheirCommitKey.SerializeCompressed()); err != nil {
return err
}
if _, err := b.Write(channel.OurCommitKey.SerializeCompressed()); err != nil {
return err
}
return nodeChanBucket.Put(commitKey, b.Bytes())
}
func deleteChanCommitKeys(nodeChanBucket *bolt.Bucket, chanID []byte) error {
commitKey := make([]byte, len(commitKeys)+len(chanID))
copy(commitKey[:3], commitKeys)
copy(commitKey[3:], chanID)
return nodeChanBucket.Delete(commitKey)
}
func fetchChanCommitKeys(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
// Construct the key which stores the commitment keys: ckk || channelID.
// TODO(roasbeef): factor into func
var bc bytes.Buffer
if err := writeOutpoint(&bc, channel.ChanID); err != nil {
return err
}
commitKey := make([]byte, len(commitKeys)+bc.Len())
copy(commitKey[:3], commitKeys)
copy(commitKey[3:], bc.Bytes())
var err error
keyBytes := nodeChanBucket.Get(commitKey)
channel.TheirCommitKey, err = btcec.ParsePubKey(keyBytes[:33], btcec.S256())
if err != nil {
return err
}
channel.OurCommitKey, err = btcec.ParsePubKey(keyBytes[33:], btcec.S256())
if err != nil {
return err
}
return nil
}
func putChanCommitTxns(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, channel.ChanID); 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.OurCommitTx.Serialize(&b); err != nil {
return err
}
if err := wire.WriteVarBytes(&b, 0, channel.OurCommitSig); err != nil {
return err
}
// TODO(roasbeef): should move this into putChanFundingInfo
scratch := make([]byte, 4)
byteOrder.PutUint32(scratch, channel.LocalCsvDelay)
if _, err := b.Write(scratch); err != nil {
return err
}
byteOrder.PutUint32(scratch, channel.RemoteCsvDelay)
if _, err := b.Write(scratch); 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.ChanID); 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.OurCommitTx = wire.NewMsgTx()
if err = channel.OurCommitTx.Deserialize(txnBytes); err != nil {
return err
}
channel.OurCommitSig, err = wire.ReadVarBytes(txnBytes, 0, 80, "")
if err != nil {
return err
}
scratch := make([]byte, 4)
if _, err := txnBytes.Read(scratch); err != nil {
return err
}
channel.LocalCsvDelay = byteOrder.Uint32(scratch)
if _, err := txnBytes.Read(scratch); err != nil {
return err
}
channel.RemoteCsvDelay = byteOrder.Uint32(scratch)
return nil
}
func putChanFundingInfo(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, channel.ChanID); err != nil {
return err
}
fundTxnKey := make([]byte, len(fundingTxnKey)+bc.Len())
copy(fundTxnKey[:3], fundingTxnKey)
copy(fundTxnKey[3:], bc.Bytes())
var b bytes.Buffer
if err := writeOutpoint(&b, channel.FundingOutpoint); err != nil {
return err
}
ourSerKey := channel.OurMultiSigKey.SerializeCompressed()
if err := wire.WriteVarBytes(&b, 0, ourSerKey); err != nil {
return err
}
theirSerKey := channel.TheirMultiSigKey.SerializeCompressed()
if err := wire.WriteVarBytes(&b, 0, theirSerKey); err != nil {
return err
}
if err := wire.WriteVarBytes(&b, 0, channel.FundingWitnessScript[:]); err != nil {
return err
}
scratch := make([]byte, 8)
byteOrder.PutUint64(scratch, uint64(channel.CreationTime.Unix()))
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.ChanID); 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))
// TODO(roasbeef): can remove as channel ID *is* the funding point now.
channel.FundingOutpoint = &wire.OutPoint{}
if err := readOutpoint(infoBytes, channel.FundingOutpoint); err != nil {
return err
}
ourKeyBytes, err := wire.ReadVarBytes(infoBytes, 0, 34, "")
if err != nil {
return err
}
channel.OurMultiSigKey, err = btcec.ParsePubKey(ourKeyBytes, btcec.S256())
if err != nil {
return err
}
theirKeyBytes, err := wire.ReadVarBytes(infoBytes, 0, 34, "")
if err != nil {
return err
}
channel.TheirMultiSigKey, err = btcec.ParsePubKey(theirKeyBytes, btcec.S256())
if err != nil {
return err
}
channel.FundingWitnessScript, err = wire.ReadVarBytes(infoBytes, 0, 520, "")
if err != nil {
return err
}
scratch := make([]byte, 8)
if _, err := infoBytes.Read(scratch); err != nil {
return err
}
unixSecs := byteOrder.Uint64(scratch)
channel.CreationTime = time.Unix(int64(unixSecs), 0)
return nil
}
func putChanElkremState(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, channel.ChanID); err != nil {
return err
}
elkremKey := make([]byte, len(elkremStateKey)+bc.Len())
copy(elkremKey[:3], elkremStateKey)
copy(elkremKey[3:], bc.Bytes())
var b bytes.Buffer
revKey := channel.TheirCurrentRevocation.SerializeCompressed()
if err := wire.WriteVarBytes(&b, 0, revKey); err != nil {
return err
}
if _, err := b.Write(channel.TheirCurrentRevocationHash[:]); err != nil {
return err
}
// TODO(roasbeef): shouldn't be storing on disk, should re-derive as
// needed
senderBytes := channel.LocalElkrem.ToBytes()
if err := wire.WriteVarBytes(&b, 0, senderBytes); err != nil {
return err
}
reciverBytes, err := channel.RemoteElkrem.ToBytes()
if err != nil {
return err
}
if err := wire.WriteVarBytes(&b, 0, reciverBytes); err != nil {
return err
}
return nodeChanBucket.Put(elkremKey, b.Bytes())
}
func deleteChanElkremState(nodeChanBucket *bolt.Bucket, chanID []byte) error {
elkremKey := make([]byte, len(elkremStateKey)+len(chanID))
copy(elkremKey[:3], elkremStateKey)
copy(elkremKey[3:], chanID)
return nodeChanBucket.Delete(elkremKey)
}
func fetchChanElkremState(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
elkremKey := make([]byte, len(elkremStateKey)+b.Len())
copy(elkremKey[:3], elkremStateKey)
copy(elkremKey[3:], b.Bytes())
elkremStateBytes := bytes.NewReader(nodeChanBucket.Get(elkremKey))
revKeyBytes, err := wire.ReadVarBytes(elkremStateBytes, 0, 1000, "")
if err != nil {
return err
}
channel.TheirCurrentRevocation, err = btcec.ParsePubKey(revKeyBytes, btcec.S256())
if err != nil {
return err
}
if _, err := elkremStateBytes.Read(channel.TheirCurrentRevocationHash[:]); err != nil {
return err
}
// TODO(roasbeef): should be rederiving on fly, or encrypting on disk.
senderBytes, err := wire.ReadVarBytes(elkremStateBytes, 0, 1000, "")
if err != nil {
return err
}
elkremRoot, err := wire.NewShaHash(senderBytes)
if err != nil {
return err
}
channel.LocalElkrem = elkrem.NewElkremSender(*elkremRoot)
reciverBytes, err := wire.ReadVarBytes(elkremStateBytes, 0, 1000, "")
if err != nil {
return err
}
remoteE, err := elkrem.ElkremReceiverFromBytes(reciverBytes)
if err != nil {
return err
}
channel.RemoteElkrem = remoteE
return nil
}
func putChanDeliveryScripts(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var bc bytes.Buffer
if err := writeOutpoint(&bc, channel.ChanID); err != nil {
return err
}
deliveryKey := make([]byte, len(deliveryScriptsKey)+bc.Len())
copy(deliveryKey[:3], deliveryScriptsKey)
copy(deliveryKey[3:], bc.Bytes())
var b bytes.Buffer
if err := wire.WriteVarBytes(&b, 0, channel.OurDeliveryScript); err != nil {
return err
}
if err := wire.WriteVarBytes(&b, 0, channel.TheirDeliveryScript); err != nil {
return err
}
return nodeChanBucket.Put(deliveryScriptsKey, b.Bytes())
}
func deleteChanDeliveryScripts(nodeChanBucket *bolt.Bucket, chanID []byte) error {
deliveryKey := make([]byte, len(deliveryScriptsKey)+len(chanID))
copy(deliveryKey[:3], deliveryScriptsKey)
copy(deliveryKey[3:], chanID)
return nodeChanBucket.Delete(deliveryScriptsKey)
}
func fetchChanDeliveryScripts(nodeChanBucket *bolt.Bucket, channel *OpenChannel) error {
var b bytes.Buffer
if err := writeOutpoint(&b, channel.ChanID); err != nil {
return err
}
deliveryKey := make([]byte, len(deliveryScriptsKey)+b.Len())
copy(deliveryKey[:3], deliveryScriptsKey)
copy(deliveryKey[3:], b.Bytes())
var err error
deliveryBytes := bytes.NewReader(nodeChanBucket.Get(deliveryScriptsKey))
channel.OurDeliveryScript, err = wire.ReadVarBytes(deliveryBytes, 0, 520, "")
if err != nil {
return err
}
channel.TheirDeliveryScript, err = wire.ReadVarBytes(deliveryBytes, 0, 520, "")
if err != nil {
return err
}
return nil
}
// htlcDiskSize represents the number of btyes a serialized HTLC takes up on
// disk. The size of an HTLC on disk is 49 bytes total: incoming (1) + amt (8)
// + rhash (32) + timeouts (8)
const htlcDiskSize = 1 + 8 + 32 + 4 + 4
func serializeHTLC(w io.Writer, h *HTLC) error {
var buf [htlcDiskSize]byte
var boolByte [1]byte
if h.Incoming {
boolByte[0] = 1
} else {
boolByte[0] = 0
}
var n int
n += copy(buf[:], boolByte[:])
byteOrder.PutUint64(buf[n:], uint64(h.Amt))
n += 8
n += copy(buf[n:], h.RHash[:])
byteOrder.PutUint32(buf[n:], h.RefundTimeout)
n += 4
byteOrder.PutUint32(buf[n:], h.RevocationDelay)
n += 4
if _, err := w.Write(buf[:]); err != nil {
return err
}
return nil
}
func deserializeHTLC(r io.Reader) (*HTLC, error) {
h := &HTLC{}
var scratch [8]byte
if _, err := r.Read(scratch[:1]); err != nil {
return nil, err
}
if scratch[0] == 1 {
h.Incoming = true
} else {
h.Incoming = false
}
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
h.Amt = btcutil.Amount(byteOrder.Uint64(scratch[:]))
if _, err := r.Read(h.RHash[:]); err != nil {
return nil, err
}
if _, err := r.Read(scratch[:4]); err != nil {
return nil, err
}
h.RefundTimeout = byteOrder.Uint32(scratch[:4])
if _, err := r.Read(scratch[:4]); err != nil {
return nil, err
}
h.RevocationDelay = byteOrder.Uint32(scratch[:])
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 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.PutUint32(scratch[:4], delta.UpdateNum)
if _, err := w.Write(scratch[:4]); 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
}
}
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 = btcutil.Amount(byteOrder.Uint64(scratch[:]))
if _, err := r.Read(scratch[:]); err != nil {
return nil, err
}
delta.RemoteBalance = btcutil.Amount(byteOrder.Uint64(scratch[:]))
if _, err := r.Read(scratch[:4]); err != nil {
return nil, err
}
delta.UpdateNum = byteOrder.Uint32(scratch[:4])
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
}
return delta, nil
}
func makeLogKey(o *wire.OutPoint, updateNum uint32) [40]byte {
var (
scratch [4]byte
n int
k [40]byte
)
n += copy(k[:], o.Hash[:])
byteOrder.PutUint32(scratch[:], o.Index)
copy(k[n:], scratch[:])
n += 4
byteOrder.PutUint32(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 uint32) (*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 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)
if _, err := w.Write(scratch); err != nil {
return err
}
return nil
}
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
}