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 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 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") theirDustLimitPrefix = []byte("tdlp") ourDustLimitPrefix = []byte("odlp") updatePrefix = []byte("uup") satSentPrefix = []byte("ssp") satReceivedPrefix = []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") ) // 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 HTLC's, 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 ) // 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 // ChanID is an identifier that uniquely identifies this channel // globally within the blockchain. ChanID *wire.OutPoint // MinFeePerKb is the min BTC/KB 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. MinFeePerKb btcutil.Amount // TheirDustLimit is the threshold below which no HTLC output should be // generated for their commitment transaction; ie. HTLCs below // this amount are not enforceable onchain from their point of view. TheirDustLimit btcutil.Amount // OurDustLimit is the threshold below which no HTLC output should be // generated for our commitment transaction; ie. HTLCs below // this amount are not enforceable onchain from out point of view. OurDustLimit btcutil.Amount // OurCommitKey is the key to be used within our commitment transaction // to generate the scripts for outputs paying to ourself, and // revocation clauses. OurCommitKey *btcec.PublicKey // TheirCommitKey is the key to be used within our commitment // transaction to generate the scripts for outputs paying to ourself, // and revocation clauses. TheirCommitKey *btcec.PublicKey // Capacity is the total capacity of this channel. // TODO(roasbeef): need another field to mark how much fees have been // allocated independent of capacity. Capacity btcutil.Amount // OurBalance is the current available settled balance within the // channel directly spendable by us. OurBalance btcutil.Amount // TheirBalance is the current available settled balance within the // channel directly spendable by the remote node. TheirBalance btcutil.Amount // OurCommitKey is the latest version of the commitment state, // broadcast able by us. OurCommitTx *wire.MsgTx // OurCommitSig is one half of the signature required to fully complete // the script for the commitment transaction above. OurCommitSig []byte // StateHintObsfucator are the btyes selected by the initiator (derived // from their shachain root) to obsfucate the state-hint encoded within // the commitment transaction. StateHintObsfucator [4]byte // ChanType denotes which type of channel this is. ChanType ChannelType // 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 // FundingOutpoint is the outpoint of the final funding transaction. FundingOutpoint *wire.OutPoint // OurMultiSigKey is the multi-sig key used within the funding // transaction that we control. OurMultiSigKey *btcec.PublicKey // TheirMultiSigKey is the multi-sig key used within the funding // transaction for the remote party. TheirMultiSigKey *btcec.PublicKey // FundingWitnessScript is the full witness script used within the // funding transaction. FundingWitnessScript []byte // LocalCsvDelay is the delay to be used in outputs paying to us within // the commitment transaction. This value is to be always expressed in // terms of relative blocks. LocalCsvDelay uint32 // RemoteCsvDelay is the delay to be used in outputs paying to the // remote party. This value is to be always expressed in terms of // relative blocks. 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 // OurDeliveryScript is the script to be used to pay to us in // cooperative closes. OurDeliveryScript []byte // OurDeliveryScript is the script to be used to pay to the remote // party in cooperative closes. TheirDeliveryScript []byte // NumUpdates is the total number of updates conducted within this // channel. NumUpdates uint64 // TotalSatoshisSent is the total number of satoshis we've sent within // this channel. TotalSatoshisSent uint64 // TotalSatoshisReceived is the total number of satoshis we've received // within this channel. TotalSatoshisReceived uint64 // CreationTime is the time this channel was initially created. CreationTime time.Time // Htlcs is the list of active, uncleared HTLC's 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. 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.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.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 := putChanAmountsTransferred(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 // OutputIndex is the output index for this particular HTLC output // within the commitment transaction. OutputIndex uint16 } // 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, OutputIndex: h.OutputIndex, } 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.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) }) } // 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{ ChanID: c.ChanID, } err := c.Db.View(func(tx *bolt.Tx) error { // Get the bucket dedicated to storing the meta-data 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 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.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 := putChanTheirDustLimit(openChanBucket, channel); err != nil { return err } if err := putChanOurDustLimit(openChanBucket, channel); err != nil { return err } if err := putChanNumUpdates(openChanBucket, channel); err != nil { return err } if err := putChanAmountsTransferred(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. 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 = fetchChanTheirDustLimit(openChanBucket, channel); err != nil { return nil, err } if err = fetchChanOurDustLimit(openChanBucket, channel); err != nil { return nil, err } if err = fetchChanNumUpdates(openChanBucket, channel); err != nil { return nil, err } if err = fetchChanAmountsTransferred(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 := deleteChanAmountsTransferred(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 putChanTheirDustLimit(openChanBucket *bolt.Bucket, channel *OpenChannel) error { scratch := make([]byte, 8) byteOrder.PutUint64(scratch, uint64(channel.TheirDustLimit)) var b bytes.Buffer if err := writeOutpoint(&b, channel.ChanID); err != nil { return err } keyPrefix := make([]byte, 3+b.Len()) copy(keyPrefix, theirDustLimitPrefix) copy(keyPrefix[3:], b.Bytes()) return openChanBucket.Put(keyPrefix, scratch) } func putChanOurDustLimit(openChanBucket *bolt.Bucket, channel *OpenChannel) error { scratch := make([]byte, 8) byteOrder.PutUint64(scratch, uint64(channel.OurDustLimit)) var b bytes.Buffer if err := writeOutpoint(&b, channel.ChanID); err != nil { return err } keyPrefix := make([]byte, 3+b.Len()) copy(keyPrefix, ourDustLimitPrefix) 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 fetchChanTheirDustLimit(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, theirDustLimitPrefix) copy(keyPrefix[3:], b.Bytes()) dustLimitBytes := openChanBucket.Get(keyPrefix) channel.TheirDustLimit = btcutil.Amount(byteOrder.Uint64(dustLimitBytes)) return nil } func fetchChanOurDustLimit(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, ourDustLimitPrefix) copy(keyPrefix[3:], b.Bytes()) dustLimitBytes := openChanBucket.Get(keyPrefix) channel.OurDustLimit = btcutil.Amount(byteOrder.Uint64(dustLimitBytes)) 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 putChanAmountsTransferred(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], satReceivedPrefix) byteOrder.PutUint64(scratch2, uint64(channel.TotalSatoshisReceived)) 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.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], satReceivedPrefix) totalReceivedBytes := openChanBucket.Get(keyPrefix) channel.TotalSatoshisReceived = byteOrder.Uint64(totalReceivedBytes) return nil } 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.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 } var boolByte [1]byte if channel.IsInitiator { boolByte[0] = 1 } else { boolByte[0] = 0 } if _, err := b.Write(boolByte[:]); err != nil { return err } if _, err := b.Write([]byte{uint8(channel.ChanType)}); 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) 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]) 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 } if _, err := b.Write(channel.StateHintObsfucator[:]); 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 _, err = io.ReadFull(elkremStateBytes, channel.StateHintObsfucator[:]) if err != nil { return err } 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) + output index (2) const htlcDiskSize = 1 + 8 + 32 + 4 + 4 + 2 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 byteOrder.PutUint16(buf[n:], h.OutputIndex) n += 2 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[:]) if _, err := io.ReadFull(r, scratch[:2]); err != nil { return nil, err } h.OutputIndex = byteOrder.Uint16(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 }