12199391122

Committed 06 Dec 2024 01:10PM UTC coverage: 49.807% (-9.1%) from 58.933%

Build # 12199391122

Build Type

push

github

Committed by

web-flow

Commit Message

Merge pull request #9337 from Guayaba221/patch-1

chore: fix typo in ruby.md

Run Details

100137 of 201051 relevant lines covered (49.81%)

2.07 hits per line

Source File
Press 'n' to go to next uncovered line, 'b' for previous

75.31

/routing/payment_session.go

package routing

import (
        "fmt"

        "github.com/btcsuite/btcd/btcec/v2"
        "github.com/btcsuite/btclog/v2"
        "github.com/lightningnetwork/lnd/channeldb"
        "github.com/lightningnetwork/lnd/graph/db/models"
        "github.com/lightningnetwork/lnd/lnutils"
        "github.com/lightningnetwork/lnd/lnwire"
        "github.com/lightningnetwork/lnd/netann"
        "github.com/lightningnetwork/lnd/routing/route"
)

// BlockPadding is used to increment the finalCltvDelta value for the last hop
// to prevent an HTLC being failed if some blocks are mined while it's in-flight.
const BlockPadding uint16 = 3

// ValidateCLTVLimit is a helper function that validates that the cltv limit is
// greater than the final cltv delta parameter, optionally including the
// BlockPadding in this calculation.
func ValidateCLTVLimit(limit uint32, delta uint16, includePad bool) error {
        if includePad {
                delta += BlockPadding
        }

        if limit <= uint32(delta) {
                return fmt.Errorf("cltv limit %v should be greater than %v",
                        limit, delta)
        }

        return nil
}

// noRouteError encodes a non-critical error encountered during path finding.
type noRouteError uint8

const (
        // errNoTlvPayload is returned when the destination hop does not support
        // a tlv payload.
        errNoTlvPayload noRouteError = iota

        // errNoPaymentAddr is returned when the destination hop does not
        // support payment addresses.
        errNoPaymentAddr

        // errNoPathFound is returned when a path to the target destination does
        // not exist in the graph.
        errNoPathFound

        // errInsufficientLocalBalance is returned when none of the local
        // channels have enough balance for the payment.
        errInsufficientBalance

        // errEmptyPaySession is returned when the empty payment session is
        // queried for a route.
        errEmptyPaySession

        // errUnknownRequiredFeature is returned when the destination node
        // requires an unknown feature.
        errUnknownRequiredFeature

        // errMissingDependentFeature is returned when the destination node
        // misses a feature that a feature that we require depends on.
        errMissingDependentFeature
)

var (
        // DefaultShardMinAmt is the default amount beyond which we won't try to
        // further split the payment if no route is found. It is the minimum
        // amount that we use as the shard size when splitting.
        DefaultShardMinAmt = lnwire.NewMSatFromSatoshis(10000)
)

// Error returns the string representation of the noRouteError.
func (e noRouteError) Error() string {
        switch e {
        case errNoTlvPayload:
                return "destination hop doesn't understand new TLV payloads"

        case errNoPaymentAddr:
                return "destination hop doesn't understand payment addresses"

        case errNoPathFound:
                return "unable to find a path to destination"

        case errEmptyPaySession:
                return "empty payment session"

        case errInsufficientBalance:
                return "insufficient local balance"

        case errUnknownRequiredFeature:
                return "unknown required feature"

        case errMissingDependentFeature:
                return "missing dependent feature"

        default:
                return "unknown no-route error"
        }
}

// FailureReason converts a path finding error into a payment-level failure.
func (e noRouteError) FailureReason() channeldb.FailureReason {
        switch e {
        case
                errNoTlvPayload,
                errNoPaymentAddr,
                errNoPathFound,
                errEmptyPaySession,
                errUnknownRequiredFeature,
                errMissingDependentFeature:

                return channeldb.FailureReasonNoRoute

        case errInsufficientBalance:
                return channeldb.FailureReasonInsufficientBalance

        default:
                return channeldb.FailureReasonError
        }
}

// PaymentSession is used during SendPayment attempts to provide routes to
// attempt. It also defines methods to give the PaymentSession additional
// information learned during the previous attempts.
type PaymentSession interface {
        // RequestRoute returns the next route to attempt for routing the
        // specified HTLC payment to the target node. The returned route should
        // carry at most maxAmt to the target node, and pay at most feeLimit in
        // fees. It can carry less if the payment is MPP. The activeShards
        // argument should be set to instruct the payment session about the
        // number of in flight HTLCS for the payment, such that it can choose
        // splitting strategy accordingly.
        //
        // A noRouteError is returned if a non-critical error is encountered
        // during path finding.
        RequestRoute(maxAmt, feeLimit lnwire.MilliSatoshi,
                activeShards, height uint32,
                firstHopCustomRecords lnwire.CustomRecords) (*route.Route,
                error)

        // UpdateAdditionalEdge takes an additional channel edge policy
        // (private channels) and applies the update from the message. Returns
        // a boolean to indicate whether the update has been applied without
        // error.
        UpdateAdditionalEdge(msg *lnwire.ChannelUpdate1,
                pubKey *btcec.PublicKey, policy *models.CachedEdgePolicy) bool

        // GetAdditionalEdgePolicy uses the public key and channel ID to query
        // the ephemeral channel edge policy for additional edges. Returns a nil
        // if nothing found.
        GetAdditionalEdgePolicy(pubKey *btcec.PublicKey,
                channelID uint64) *models.CachedEdgePolicy
}

// paymentSession is used during an HTLC routings session to prune the local
// chain view in response to failures, and also report those failures back to
// MissionController. The snapshot copied for this session will only ever grow,
// and will now be pruned after a decay like the main view within mission
// control. We do this as we want to avoid the case where we continually try a
// bad edge or route multiple times in a session. This can lead to an infinite
// loop if payment attempts take long enough. An additional set of edges can
// also be provided to assist in reaching the payment's destination.
type paymentSession struct {
        selfNode route.Vertex

        additionalEdges map[route.Vertex][]AdditionalEdge

        getBandwidthHints func(Graph) (bandwidthHints, error)

        payment *LightningPayment

        empty bool

        pathFinder pathFinder

        graphSessFactory GraphSessionFactory

        // pathFindingConfig defines global parameters that control the
        // trade-off in path finding between fees and probability.
        pathFindingConfig PathFindingConfig

        missionControl MissionControlQuerier

        // minShardAmt is the amount beyond which we won't try to further split
        // the payment if no route is found. If the maximum number of htlcs
        // specified in the payment is one, under no circumstances splitting
        // will happen and this value remains unused.
        minShardAmt lnwire.MilliSatoshi

        // log is a payment session-specific logger.
        log btclog.Logger
}

// newPaymentSession instantiates a new payment session.
func newPaymentSession(p *LightningPayment, selfNode route.Vertex,
        getBandwidthHints func(Graph) (bandwidthHints, error),
        graphSessFactory GraphSessionFactory,
        missionControl MissionControlQuerier,
        pathFindingConfig PathFindingConfig) (*paymentSession, error) {

        edges, err := RouteHintsToEdges(p.RouteHints, p.Target)
        if err != nil {
                return nil, err
        }

        if p.BlindedPathSet != nil {
                if len(edges) != 0 {
                        return nil, fmt.Errorf("cannot have both route hints " +
                                "and blinded path")
                }

                edges, err = p.BlindedPathSet.ToRouteHints()
                if err != nil {
                        return nil, err
                }
        }

        logPrefix := fmt.Sprintf("PaymentSession(%x):", p.Identifier())

        return &paymentSession{
                selfNode:          selfNode,
                additionalEdges:   edges,
                getBandwidthHints: getBandwidthHints,
                payment:           p,
                pathFinder:        findPath,
                graphSessFactory:  graphSessFactory,
                pathFindingConfig: pathFindingConfig,
                missionControl:    missionControl,
                minShardAmt:       DefaultShardMinAmt,
                log:               log.WithPrefix(logPrefix),
        }, nil
}

// RequestRoute returns a route which is likely to be capable for successfully
// routing the specified HTLC payment to the target node. Initially the first
// set of paths returned from this method may encounter routing failure along
// the way, however as more payments are sent, mission control will start to
// build an up to date view of the network itself. With each payment a new area
// will be explored, which feeds into the recommendations made for routing.
//
// NOTE: This function is safe for concurrent access.
// NOTE: Part of the PaymentSession interface.
func (p *paymentSession) RequestRoute(maxAmt, feeLimit lnwire.MilliSatoshi,
        activeShards, height uint32,
        firstHopCustomRecords lnwire.CustomRecords) (*route.Route, error) {

        if p.empty {
                return nil, errEmptyPaySession
        }

        // Add BlockPadding to the finalCltvDelta so that the receiving node
        // does not reject the HTLC if some blocks are mined while it's in-flight.
        finalCltvDelta := p.payment.FinalCLTVDelta
        finalCltvDelta += BlockPadding

        // We need to subtract the final delta before passing it into path
        // finding. The optimal path is independent of the final cltv delta and
        // the path finding algorithm is unaware of this value.
        cltvLimit := p.payment.CltvLimit - uint32(finalCltvDelta)

        // TODO(roasbeef): sync logic amongst dist sys

        // Taking into account this prune view, we'll attempt to locate a path
        // to our destination, respecting the recommendations from
        // MissionController.
        restrictions := &RestrictParams{
                ProbabilitySource:     p.missionControl.GetProbability,
                FeeLimit:              feeLimit,
                OutgoingChannelIDs:    p.payment.OutgoingChannelIDs,
                LastHop:               p.payment.LastHop,
                CltvLimit:             cltvLimit,
                DestCustomRecords:     p.payment.DestCustomRecords,
                DestFeatures:          p.payment.DestFeatures,
                PaymentAddr:           p.payment.PaymentAddr,
                Amp:                   p.payment.amp,
                Metadata:              p.payment.Metadata,
                FirstHopCustomRecords: firstHopCustomRecords,
        }

        finalHtlcExpiry := int32(height) + int32(finalCltvDelta)

        // Before we enter the loop below, we'll make sure to respect the max
        // payment shard size (if it's set), which is effectively our
        // client-side MTU that we'll attempt to respect at all times.
        maxShardActive := p.payment.MaxShardAmt != nil
        if maxShardActive && maxAmt > *p.payment.MaxShardAmt {
                p.log.Debugf("Clamping payment attempt from %v to %v due to "+
                        "max shard size of %v", maxAmt, *p.payment.MaxShardAmt,
                        maxAmt)

                maxAmt = *p.payment.MaxShardAmt
        }

        for {
                // Get a routing graph session.
                graph, closeGraph, err := p.graphSessFactory.NewGraphSession()
                if err != nil {
                        return nil, err
                }

                // We'll also obtain a set of bandwidthHints from the lower
                // layer for each of our outbound channels. This will allow the
                // path finding to skip any links that aren't active or just
                // don't have enough bandwidth to carry the payment. New
                // bandwidth hints are queried for every new path finding
                // attempt, because concurrent payments may change balances.
                bandwidthHints, err := p.getBandwidthHints(graph)
                if err != nil {
                        // Close routing graph session.
                        if graphErr := closeGraph(); graphErr != nil {
                                log.Errorf("could not close graph session: %v",
                                        graphErr)
                        }

                        return nil, err
                }

                p.log.Debugf("pathfinding for amt=%v", maxAmt)

                // Find a route for the current amount.
                path, _, err := p.pathFinder(
                        &graphParams{
                                additionalEdges: p.additionalEdges,
                                bandwidthHints:  bandwidthHints,
                                graph:           graph,
                        },
                        restrictions, &p.pathFindingConfig,
                        p.selfNode, p.selfNode, p.payment.Target,
                        maxAmt, p.payment.TimePref, finalHtlcExpiry,
                )

                // Close routing graph session.
                if err := closeGraph(); err != nil {
                        log.Errorf("could not close graph session: %v", err)
                }

                switch {
                case err == errNoPathFound:
                        // Don't split if this is a legacy payment without mpp
                        // record. If it has a blinded path though, then we
                        // can split. Split payments to blinded paths won't have
                        // MPP records.
                        if p.payment.PaymentAddr.IsNone() &&
                                p.payment.BlindedPathSet == nil {

                                p.log.Debugf("not splitting because payment " +
                                        "address is unspecified")

                                return nil, errNoPathFound
                        }

                        if p.payment.DestFeatures == nil {
                                p.log.Debug("Not splitting because " +
                                        "destination DestFeatures is nil")
                                return nil, errNoPathFound
                        }

                        destFeatures := p.payment.DestFeatures
                        if !destFeatures.HasFeature(lnwire.MPPOptional) &&
                                !destFeatures.HasFeature(lnwire.AMPOptional) {

                                p.log.Debug("not splitting because " +
                                        "destination doesn't declare MPP or " +
                                        "AMP")

                                return nil, errNoPathFound
                        }

                        // No splitting if this is the last shard.
                        isLastShard := activeShards+1 >= p.payment.MaxParts
                        if isLastShard {
                                p.log.Debugf("not splitting because shard "+
                                        "limit %v has been reached",
                                        p.payment.MaxParts)

                                return nil, errNoPathFound
                        }

                        // This is where the magic happens. If we can't find a
                        // route, try it for half the amount.
                        maxAmt /= 2

                        // Put a lower bound on the minimum shard size.
                        if maxAmt < p.minShardAmt {
                                p.log.Debugf("not splitting because minimum "+
                                        "shard amount %v has been reached",
                                        p.minShardAmt)

                                return nil, errNoPathFound
                        }

                        // Go pathfinding.
                        continue

                // If there isn't enough local bandwidth, there is no point in
                // splitting. It won't be possible to create a complete set in
                // any case, but the sent out partial payments would be held by
                // the receiver until the mpp timeout.
                case err == errInsufficientBalance:
                        p.log.Debug("not splitting because local balance " +
                                "is insufficient")

                        return nil, err

                case err != nil:
                        return nil, err
                }

                // With the next candidate path found, we'll attempt to turn
                // this into a route by applying the time-lock and fee
                // requirements.
                route, err := newRoute(
                        p.selfNode, path, height,
                        finalHopParams{
                                amt:         maxAmt,
                                totalAmt:    p.payment.Amount,
                                cltvDelta:   finalCltvDelta,
                                records:     p.payment.DestCustomRecords,
                                paymentAddr: p.payment.PaymentAddr,
                                metadata:    p.payment.Metadata,
                        }, p.payment.BlindedPathSet,
                )
                if err != nil {
                        return nil, err
                }

                return route, err
        }
}

// UpdateAdditionalEdge updates the channel edge policy for a private edge. It
// validates the message signature and checks it's up to date, then applies the
// updates to the supplied policy. It returns a boolean to indicate whether
// there's an error when applying the updates.
func (p *paymentSession) UpdateAdditionalEdge(msg *lnwire.ChannelUpdate1,
        pubKey *btcec.PublicKey, policy *models.CachedEdgePolicy) bool {

        // Validate the message signature.
        if err := netann.VerifyChannelUpdateSignature(msg, pubKey); err != nil {
                log.Errorf(
                        "Unable to validate channel update signature: %v", err,
                )
                return false
        }

        // Update channel policy for the additional edge.
        policy.TimeLockDelta = msg.TimeLockDelta
        policy.FeeBaseMSat = lnwire.MilliSatoshi(msg.BaseFee)
        policy.FeeProportionalMillionths = lnwire.MilliSatoshi(msg.FeeRate)

        log.Debugf("New private channel update applied: %v",
                lnutils.SpewLogClosure(msg))

        return true
}

// GetAdditionalEdgePolicy uses the public key and channel ID to query the
// ephemeral channel edge policy for additional edges. Returns a nil if nothing
// found.
func (p *paymentSession) GetAdditionalEdgePolicy(pubKey *btcec.PublicKey,
        channelID uint64) *models.CachedEdgePolicy {

        target := route.NewVertex(pubKey)

        edges, ok := p.additionalEdges[target]
        if !ok {
                return nil
        }

        for _, edge := range edges {
                policy := edge.EdgePolicy()
                if policy.ChannelID != channelID {
                        continue
                }

                return policy
        }

        return nil
}

1	package routing
2
3	import (
4	"fmt"
5
6	"github.com/btcsuite/btcd/btcec/v2"
7	"github.com/btcsuite/btclog/v2"
8	"github.com/lightningnetwork/lnd/channeldb"
9	"github.com/lightningnetwork/lnd/graph/db/models"
10	"github.com/lightningnetwork/lnd/lnutils"
11	"github.com/lightningnetwork/lnd/lnwire"
12	"github.com/lightningnetwork/lnd/netann"
13	"github.com/lightningnetwork/lnd/routing/route"
14	)
15
16	// BlockPadding is used to increment the finalCltvDelta value for the last hop
17	// to prevent an HTLC being failed if some blocks are mined while it's in-flight.
18	const BlockPadding uint16 = 3
19
20	// ValidateCLTVLimit is a helper function that validates that the cltv limit is
21	// greater than the final cltv delta parameter, optionally including the
22	// BlockPadding in this calculation.
23	func ValidateCLTVLimit(limit uint32, delta uint16, includePad bool) error {	4✔
24	if includePad {	8✔
25	delta += BlockPadding	4✔
26	}	4✔
27
28	if limit <= uint32(delta) {	4✔
29	return fmt.Errorf("cltv limit %v should be greater than %v",	×
30	limit, delta)	×
31	}	×
32
33	return nil	4✔
34	}
35
36	// noRouteError encodes a non-critical error encountered during path finding.
37	type noRouteError uint8
38
39	const (
40	// errNoTlvPayload is returned when the destination hop does not support
41	// a tlv payload.
42	errNoTlvPayload noRouteError = iota
43
44	// errNoPaymentAddr is returned when the destination hop does not
45	// support payment addresses.
46	errNoPaymentAddr
47
48	// errNoPathFound is returned when a path to the target destination does
49	// not exist in the graph.
50	errNoPathFound
51
52	// errInsufficientLocalBalance is returned when none of the local
53	// channels have enough balance for the payment.
54	errInsufficientBalance
55
56	// errEmptyPaySession is returned when the empty payment session is
57	// queried for a route.
58	errEmptyPaySession
59
60	// errUnknownRequiredFeature is returned when the destination node
61	// requires an unknown feature.
62	errUnknownRequiredFeature
63
64	// errMissingDependentFeature is returned when the destination node
65	// misses a feature that a feature that we require depends on.
66	errMissingDependentFeature
67	)
68
69	var (
70	// DefaultShardMinAmt is the default amount beyond which we won't try to
71	// further split the payment if no route is found. It is the minimum
72	// amount that we use as the shard size when splitting.
73	DefaultShardMinAmt = lnwire.NewMSatFromSatoshis(10000)
74	)
75
76	// Error returns the string representation of the noRouteError.
77	func (e noRouteError) Error() string {	4✔
78	switch e {	4✔
79	case errNoTlvPayload:	×
80	return "destination hop doesn't understand new TLV payloads"	×
81
82	case errNoPaymentAddr:	×
83	return "destination hop doesn't understand payment addresses"	×
84
85	case errNoPathFound:	4✔
86	return "unable to find a path to destination"	4✔
87
88	case errEmptyPaySession:	4✔
89	return "empty payment session"	4✔
90
91	case errInsufficientBalance:	4✔
92	return "insufficient local balance"	4✔
93
94	case errUnknownRequiredFeature:	×
95	return "unknown required feature"	×
96
97	case errMissingDependentFeature:	×
98	return "missing dependent feature"	×
99
100	default:	×
101	return "unknown no-route error"	×
102	}
103	}
104
105	// FailureReason converts a path finding error into a payment-level failure.
106	func (e noRouteError) FailureReason() channeldb.FailureReason {	4✔
107	switch e {	4✔
108	case
109	errNoTlvPayload,
110	errNoPaymentAddr,
111	errNoPathFound,
112	errEmptyPaySession,
113	errUnknownRequiredFeature,
114	errMissingDependentFeature:	4✔
115		4✔
116	return channeldb.FailureReasonNoRoute	4✔
117
118	case errInsufficientBalance:	4✔
119	return channeldb.FailureReasonInsufficientBalance	4✔
120
121	default:	×
122	return channeldb.FailureReasonError	×
123	}
124	}
125
126	// PaymentSession is used during SendPayment attempts to provide routes to
127	// attempt. It also defines methods to give the PaymentSession additional
128	// information learned during the previous attempts.
129	type PaymentSession interface {
130	// RequestRoute returns the next route to attempt for routing the
131	// specified HTLC payment to the target node. The returned route should
132	// carry at most maxAmt to the target node, and pay at most feeLimit in
133	// fees. It can carry less if the payment is MPP. The activeShards
134	// argument should be set to instruct the payment session about the
135	// number of in flight HTLCS for the payment, such that it can choose
136	// splitting strategy accordingly.
137	//
138	// A noRouteError is returned if a non-critical error is encountered
139	// during path finding.
140	RequestRoute(maxAmt, feeLimit lnwire.MilliSatoshi,
141	activeShards, height uint32,
142	firstHopCustomRecords lnwire.CustomRecords) (*route.Route,
143	error)
144
145	// UpdateAdditionalEdge takes an additional channel edge policy
146	// (private channels) and applies the update from the message. Returns
147	// a boolean to indicate whether the update has been applied without
148	// error.
149	UpdateAdditionalEdge(msg *lnwire.ChannelUpdate1,
150	pubKey btcec.PublicKey, policy models.CachedEdgePolicy) bool
151
152	// GetAdditionalEdgePolicy uses the public key and channel ID to query
153	// the ephemeral channel edge policy for additional edges. Returns a nil
154	// if nothing found.
155	GetAdditionalEdgePolicy(pubKey *btcec.PublicKey,
156	channelID uint64) *models.CachedEdgePolicy
157	}
158
159	// paymentSession is used during an HTLC routings session to prune the local
160	// chain view in response to failures, and also report those failures back to
161	// MissionController. The snapshot copied for this session will only ever grow,
162	// and will now be pruned after a decay like the main view within mission
163	// control. We do this as we want to avoid the case where we continually try a
164	// bad edge or route multiple times in a session. This can lead to an infinite
165	// loop if payment attempts take long enough. An additional set of edges can
166	// also be provided to assist in reaching the payment's destination.
167	type paymentSession struct {
168	selfNode route.Vertex
169
170	additionalEdges map[route.Vertex][]AdditionalEdge
171
172	getBandwidthHints func(Graph) (bandwidthHints, error)
173
174	payment *LightningPayment
175
176	empty bool
177
178	pathFinder pathFinder
179
180	graphSessFactory GraphSessionFactory
181
182	// pathFindingConfig defines global parameters that control the
183	// trade-off in path finding between fees and probability.
184	pathFindingConfig PathFindingConfig
185
186	missionControl MissionControlQuerier
187
188	// minShardAmt is the amount beyond which we won't try to further split
189	// the payment if no route is found. If the maximum number of htlcs
190	// specified in the payment is one, under no circumstances splitting
191	// will happen and this value remains unused.
192	minShardAmt lnwire.MilliSatoshi
193
194	// log is a payment session-specific logger.
195	log btclog.Logger
196	}
197
198	// newPaymentSession instantiates a new payment session.
199	func newPaymentSession(p *LightningPayment, selfNode route.Vertex,
200	getBandwidthHints func(Graph) (bandwidthHints, error),
201	graphSessFactory GraphSessionFactory,
202	missionControl MissionControlQuerier,
203	pathFindingConfig PathFindingConfig) (*paymentSession, error) {	4✔
204		4✔
205	edges, err := RouteHintsToEdges(p.RouteHints, p.Target)	4✔
206	if err != nil {	4✔
207	return nil, err	×
208	}	×
209
210	if p.BlindedPathSet != nil {	8✔
211	if len(edges) != 0 {	4✔
212	return nil, fmt.Errorf("cannot have both route hints " +	×
213	"and blinded path")	×
214	}	×
215
216	edges, err = p.BlindedPathSet.ToRouteHints()	4✔
217	if err != nil {	4✔
218	return nil, err	×
219	}	×
220	}
221
222	logPrefix := fmt.Sprintf("PaymentSession(%x):", p.Identifier())	4✔
223		4✔
224	return &paymentSession{	4✔
225	selfNode: selfNode,	4✔
226	additionalEdges: edges,	4✔
227	getBandwidthHints: getBandwidthHints,	4✔
228	payment: p,	4✔
229	pathFinder: findPath,	4✔
230	graphSessFactory: graphSessFactory,	4✔
231	pathFindingConfig: pathFindingConfig,	4✔
232	missionControl: missionControl,	4✔
233	minShardAmt: DefaultShardMinAmt,	4✔
234	log: log.WithPrefix(logPrefix),	4✔
235	}, nil	4✔
236	}
237
238	// RequestRoute returns a route which is likely to be capable for successfully
239	// routing the specified HTLC payment to the target node. Initially the first
240	// set of paths returned from this method may encounter routing failure along
241	// the way, however as more payments are sent, mission control will start to
242	// build an up to date view of the network itself. With each payment a new area
243	// will be explored, which feeds into the recommendations made for routing.
244	//
245	// NOTE: This function is safe for concurrent access.
246	// NOTE: Part of the PaymentSession interface.
247	func (p *paymentSession) RequestRoute(maxAmt, feeLimit lnwire.MilliSatoshi,
248	activeShards, height uint32,
249	firstHopCustomRecords lnwire.CustomRecords) (*route.Route, error) {	4✔
250		4✔
251	if p.empty {	8✔
252	return nil, errEmptyPaySession	4✔
253	}	4✔
254
255	// Add BlockPadding to the finalCltvDelta so that the receiving node
256	// does not reject the HTLC if some blocks are mined while it's in-flight.
257	finalCltvDelta := p.payment.FinalCLTVDelta	4✔
258	finalCltvDelta += BlockPadding	4✔
259		4✔
260	// We need to subtract the final delta before passing it into path	4✔
261	// finding. The optimal path is independent of the final cltv delta and	4✔
262	// the path finding algorithm is unaware of this value.	4✔
263	cltvLimit := p.payment.CltvLimit - uint32(finalCltvDelta)	4✔
264		4✔
265	// TODO(roasbeef): sync logic amongst dist sys	4✔
266		4✔
267	// Taking into account this prune view, we'll attempt to locate a path	4✔
268	// to our destination, respecting the recommendations from	4✔
269	// MissionController.	4✔
270	restrictions := &RestrictParams{	4✔
271	ProbabilitySource: p.missionControl.GetProbability,	4✔
272	FeeLimit: feeLimit,	4✔
273	OutgoingChannelIDs: p.payment.OutgoingChannelIDs,	4✔
274	LastHop: p.payment.LastHop,	4✔
275	CltvLimit: cltvLimit,	4✔
276	DestCustomRecords: p.payment.DestCustomRecords,	4✔
277	DestFeatures: p.payment.DestFeatures,	4✔
278	PaymentAddr: p.payment.PaymentAddr,	4✔
279	Amp: p.payment.amp,	4✔
280	Metadata: p.payment.Metadata,	4✔
281	FirstHopCustomRecords: firstHopCustomRecords,	4✔
282	}	4✔
283		4✔
284	finalHtlcExpiry := int32(height) + int32(finalCltvDelta)	4✔
285		4✔
286	// Before we enter the loop below, we'll make sure to respect the max	4✔
287	// payment shard size (if it's set), which is effectively our	4✔
288	// client-side MTU that we'll attempt to respect at all times.	4✔
289	maxShardActive := p.payment.MaxShardAmt != nil	4✔
290	if maxShardActive && maxAmt > *p.payment.MaxShardAmt {	4✔
291	p.log.Debugf("Clamping payment attempt from %v to %v due to "+	×
292	"max shard size of %v", maxAmt, *p.payment.MaxShardAmt,	×
293	maxAmt)	×
294		×
295	maxAmt = *p.payment.MaxShardAmt	×
296	}	×
297
298	for {	8✔
299	// Get a routing graph session.	4✔
300	graph, closeGraph, err := p.graphSessFactory.NewGraphSession()	4✔
301	if err != nil {	4✔
302	return nil, err	×
303	}	×
304
305	// We'll also obtain a set of bandwidthHints from the lower
306	// layer for each of our outbound channels. This will allow the
307	// path finding to skip any links that aren't active or just
308	// don't have enough bandwidth to carry the payment. New
309	// bandwidth hints are queried for every new path finding
310	// attempt, because concurrent payments may change balances.
311	bandwidthHints, err := p.getBandwidthHints(graph)	4✔
312	if err != nil {	4✔
313	// Close routing graph session.	×
314	if graphErr := closeGraph(); graphErr != nil {	×
315	log.Errorf("could not close graph session: %v",	×
316	graphErr)	×
317	}	×
318
319	return nil, err	×
320	}
321
322	p.log.Debugf("pathfinding for amt=%v", maxAmt)	4✔
323		4✔
324	// Find a route for the current amount.	4✔
325	path, _, err := p.pathFinder(	4✔
326	&graphParams{	4✔
327	additionalEdges: p.additionalEdges,	4✔
328	bandwidthHints: bandwidthHints,	4✔
329	graph: graph,	4✔
330	},	4✔
331	restrictions, &p.pathFindingConfig,	4✔
332	p.selfNode, p.selfNode, p.payment.Target,	4✔
333	maxAmt, p.payment.TimePref, finalHtlcExpiry,	4✔
334	)	4✔
335		4✔
336	// Close routing graph session.	4✔
337	if err := closeGraph(); err != nil {	4✔
338	log.Errorf("could not close graph session: %v", err)	×
339	}	×
340
341	switch {	4✔
342	case err == errNoPathFound:	4✔
343	// Don't split if this is a legacy payment without mpp	4✔
344	// record. If it has a blinded path though, then we	4✔
345	// can split. Split payments to blinded paths won't have	4✔
346	// MPP records.	4✔
347	if p.payment.PaymentAddr.IsNone() &&	4✔
348	p.payment.BlindedPathSet == nil {	8✔
349		4✔
350	p.log.Debugf("not splitting because payment " +	4✔
351	"address is unspecified")	4✔
352		4✔
353	return nil, errNoPathFound	4✔
354	}	4✔
355
356	if p.payment.DestFeatures == nil {	4✔
357	p.log.Debug("Not splitting because " +	×
358	"destination DestFeatures is nil")	×
359	return nil, errNoPathFound	×
360	}	×
361
362	destFeatures := p.payment.DestFeatures	4✔
363	if !destFeatures.HasFeature(lnwire.MPPOptional) &&	4✔
364	!destFeatures.HasFeature(lnwire.AMPOptional) {	4✔
365		×
366	p.log.Debug("not splitting because " +	×
367	"destination doesn't declare MPP or " +	×
368	"AMP")	×
369		×
370	return nil, errNoPathFound	×
371	}	×
372
373	// No splitting if this is the last shard.
374	isLastShard := activeShards+1 >= p.payment.MaxParts	4✔
375	if isLastShard {	8✔
376	p.log.Debugf("not splitting because shard "+	4✔
377	"limit %v has been reached",	4✔
378	p.payment.MaxParts)	4✔
379		4✔
380	return nil, errNoPathFound	4✔
381	}	4✔
382
383	// This is where the magic happens. If we can't find a
384	// route, try it for half the amount.
385	maxAmt /= 2	4✔
386		4✔
387	// Put a lower bound on the minimum shard size.	4✔
388	if maxAmt < p.minShardAmt {	8✔
389	p.log.Debugf("not splitting because minimum "+	4✔
390	"shard amount %v has been reached",	4✔
391	p.minShardAmt)	4✔
392		4✔
393	return nil, errNoPathFound	4✔
394	}	4✔
395
396	// Go pathfinding.
397	continue	4✔
398
399	// If there isn't enough local bandwidth, there is no point in
400	// splitting. It won't be possible to create a complete set in
401	// any case, but the sent out partial payments would be held by
402	// the receiver until the mpp timeout.
403	case err == errInsufficientBalance:	4✔
404	p.log.Debug("not splitting because local balance " +	4✔
405	"is insufficient")	4✔
406		4✔
407	return nil, err	4✔
408
409	case err != nil:	×
410	return nil, err	×
411	}
412
413	// With the next candidate path found, we'll attempt to turn
414	// this into a route by applying the time-lock and fee
415	// requirements.
416	route, err := newRoute(	4✔
417	p.selfNode, path, height,	4✔
418	finalHopParams{	4✔
419	amt: maxAmt,	4✔
420	totalAmt: p.payment.Amount,	4✔
421	cltvDelta: finalCltvDelta,	4✔
422	records: p.payment.DestCustomRecords,	4✔
423	paymentAddr: p.payment.PaymentAddr,	4✔
424	metadata: p.payment.Metadata,	4✔
425	}, p.payment.BlindedPathSet,	4✔
426	)	4✔
427	if err != nil {	4✔
428	return nil, err	×
429	}	×
430
431	return route, err	4✔
432	}
433	}
434
435	// UpdateAdditionalEdge updates the channel edge policy for a private edge. It
436	// validates the message signature and checks it's up to date, then applies the
437	// updates to the supplied policy. It returns a boolean to indicate whether
438	// there's an error when applying the updates.
439	func (p paymentSession) UpdateAdditionalEdge(msg lnwire.ChannelUpdate1,
440	pubKey btcec.PublicKey, policy models.CachedEdgePolicy) bool {	4✔
441		4✔
442	// Validate the message signature.	4✔
443	if err := netann.VerifyChannelUpdateSignature(msg, pubKey); err != nil {	4✔
444	log.Errorf(	×
445	"Unable to validate channel update signature: %v", err,	×
446	)	×
447	return false	×
448	}	×
449
450	// Update channel policy for the additional edge.
451	policy.TimeLockDelta = msg.TimeLockDelta	4✔
452	policy.FeeBaseMSat = lnwire.MilliSatoshi(msg.BaseFee)	4✔
453	policy.FeeProportionalMillionths = lnwire.MilliSatoshi(msg.FeeRate)	4✔
454		4✔
455	log.Debugf("New private channel update applied: %v",	4✔
456	lnutils.SpewLogClosure(msg))	4✔
457		4✔
458	return true	4✔
459	}
460
461	// GetAdditionalEdgePolicy uses the public key and channel ID to query the
462	// ephemeral channel edge policy for additional edges. Returns a nil if nothing
463	// found.
464	func (p paymentSession) GetAdditionalEdgePolicy(pubKey btcec.PublicKey,
465	channelID uint64) *models.CachedEdgePolicy {	4✔
466		4✔
467	target := route.NewVertex(pubKey)	4✔
468		4✔
469	edges, ok := p.additionalEdges[target]	4✔
470	if !ok {	8✔
471	return nil	4✔
472	}	4✔
473
474	for _, edge := range edges {	8✔
475	policy := edge.EdgePolicy()	4✔
476	if policy.ChannelID != channelID {	4✔
477	continue	×
478	}
479
480	return policy	4✔
481	}
482
483	return nil	×
484	}

lightningnetwork / lnd / 12199391122

Source File Press 'n' to go to next uncovered line, 'b' for previous

Source File
Press 'n' to go to next uncovered line, 'b' for previous