Merge pull request #4285 from cfromknecht/pay-addr-index

channeldb: index payments by payment addr, use payment hash as fallback

channeldb/db.go

@@ -13,6 +13,7 @@ import (
 	"github.com/btcsuite/btcwallet/walletdb"
 	"github.com/go-errors/errors"
 	"github.com/lightningnetwork/lnd/channeldb/kvdb"
+	mig "github.com/lightningnetwork/lnd/channeldb/migration"
 	"github.com/lightningnetwork/lnd/channeldb/migration12"
 	"github.com/lightningnetwork/lnd/channeldb/migration13"
 	"github.com/lightningnetwork/lnd/channeldb/migration_01_to_11"
@@ -136,6 +137,13 @@ var (
 			number:    13,
 			migration: migration13.MigrateMPP,
 		},
+		{
+			// Initialize payment address index and begin using it
+			// as the default index, falling back to payment hash
+			// index.
+			number:    14,
+			migration: mig.CreateTLB(payAddrIndexBucket),
+		},
 	}
 
 	// Big endian is the preferred byte order, due to cursor scans over
@@ -242,48 +250,32 @@ func (d *DB) Path() string {
 	return d.dbPath
 }
 
+var topLevelBuckets = [][]byte{
+	openChannelBucket,
+	closedChannelBucket,
+	forwardingLogBucket,
+	fwdPackagesKey,
+	invoiceBucket,
+	payAddrIndexBucket,
+	nodeInfoBucket,
+	nodeBucket,
+	edgeBucket,
+	edgeIndexBucket,
+	graphMetaBucket,
+	metaBucket,
+}
+
 // Wipe completely deletes all saved state within all used buckets within the
 // database. The deletion is done in a single transaction, therefore this
 // operation is fully atomic.
 func (d *DB) Wipe() error {
 	return kvdb.Update(d, func(tx kvdb.RwTx) error {
-		err := tx.DeleteTopLevelBucket(openChannelBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
+		for _, tlb := range topLevelBuckets {
+			err := tx.DeleteTopLevelBucket(tlb)
+			if err != nil && err != kvdb.ErrBucketNotFound {
+				return err
+			}
 		}
-
-		err = tx.DeleteTopLevelBucket(closedChannelBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-
-		err = tx.DeleteTopLevelBucket(invoiceBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-
-		err = tx.DeleteTopLevelBucket(nodeInfoBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-
-		err = tx.DeleteTopLevelBucket(nodeBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-		err = tx.DeleteTopLevelBucket(edgeBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-		err = tx.DeleteTopLevelBucket(edgeIndexBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-		err = tx.DeleteTopLevelBucket(graphMetaBucket)
-		if err != nil && err != kvdb.ErrBucketNotFound {
-			return err
-		}
-
 		return nil
 	})
 }
@@ -301,33 +293,13 @@ func initChannelDB(db kvdb.Backend) error {
 			return nil
 		}
 
-		if _, err := tx.CreateTopLevelBucket(openChannelBucket); err != nil {
-			return err
-		}
-		if _, err := tx.CreateTopLevelBucket(closedChannelBucket); err != nil {
-			return err
+		for _, tlb := range topLevelBuckets {
+			if _, err := tx.CreateTopLevelBucket(tlb); err != nil {
+				return err
+			}
 		}
 
-		if _, err := tx.CreateTopLevelBucket(forwardingLogBucket); err != nil {
-			return err
-		}
-
-		if _, err := tx.CreateTopLevelBucket(fwdPackagesKey); err != nil {
-			return err
-		}
-
-		if _, err := tx.CreateTopLevelBucket(invoiceBucket); err != nil {
-			return err
-		}
-
-		if _, err := tx.CreateTopLevelBucket(nodeInfoBucket); err != nil {
-			return err
-		}
-
-		nodes, err := tx.CreateTopLevelBucket(nodeBucket)
-		if err != nil {
-			return err
-		}
+		nodes := tx.ReadWriteBucket(nodeBucket)
 		_, err = nodes.CreateBucket(aliasIndexBucket)
 		if err != nil {
 			return err
@@ -337,10 +309,7 @@ func initChannelDB(db kvdb.Backend) error {
 			return err
 		}
 
-		edges, err := tx.CreateTopLevelBucket(edgeBucket)
-		if err != nil {
-			return err
-		}
+		edges := tx.ReadWriteBucket(edgeBucket)
 		if _, err := edges.CreateBucket(edgeIndexBucket); err != nil {
 			return err
 		}
@@ -354,19 +323,12 @@ func initChannelDB(db kvdb.Backend) error {
 			return err
 		}
 
-		graphMeta, err := tx.CreateTopLevelBucket(graphMetaBucket)
-		if err != nil {
-			return err
-		}
+		graphMeta := tx.ReadWriteBucket(graphMetaBucket)
 		_, err = graphMeta.CreateBucket(pruneLogBucket)
 		if err != nil {
 			return err
 		}
 
-		if _, err := tx.CreateTopLevelBucket(metaBucket); err != nil {
-			return err
-		}
-
 		meta.DbVersionNumber = getLatestDBVersion(dbVersions)
 		return putMeta(meta, tx)
 	})

channeldb/error.go

@@ -43,6 +43,14 @@ var (
 	// payment hash already exists.
 	ErrDuplicateInvoice = fmt.Errorf("invoice with payment hash already exists")
 
+	// ErrDuplicatePayAddr is returned when an invoice with the target
+	// payment addr already exists.
+	ErrDuplicatePayAddr = fmt.Errorf("invoice with payemnt addr already exists")
+
+	// ErrInvRefEquivocation is returned when an InvoiceRef targets
+	// multiple, distinct invoices.
+	ErrInvRefEquivocation = errors.New("inv ref matches multiple invoices")
+
 	// ErrNoPaymentsCreated is returned when bucket of payments hasn't been
 	// created.
 	ErrNoPaymentsCreated = fmt.Errorf("there are no existing payments")

channeldb/invoice_test.go

@@ -20,16 +20,20 @@ var (
 )
 
 func randInvoice(value lnwire.MilliSatoshi) (*Invoice, error) {
-	var pre [32]byte
+	var pre, payAddr [32]byte
 	if _, err := rand.Read(pre[:]); err != nil {
 		return nil, err
 	}
+	if _, err := rand.Read(payAddr[:]); err != nil {
+		return nil, err
+	}
 
 	i := &Invoice{
 		CreationDate: testNow,
 		Terms: ContractTerm{
 			Expiry:          4000,
 			PaymentPreimage: pre,
+			PaymentAddr:     payAddr,
 			Value:           value,
 			Features:        emptyFeatures,
 		},
@@ -91,9 +95,45 @@ func TestInvoiceIsPending(t *testing.T) {
 	}
 }
 
+type invWorkflowTest struct {
+	name         string
+	queryPayHash bool
+	queryPayAddr bool
+}
+
+var invWorkflowTests = []invWorkflowTest{
+	{
+		name:         "unknown",
+		queryPayHash: false,
+		queryPayAddr: false,
+	},
+	{
+		name:         "only payhash known",
+		queryPayHash: true,
+		queryPayAddr: false,
+	},
+	{
+		name:         "payaddr and payhash known",
+		queryPayHash: true,
+		queryPayAddr: true,
+	},
+}
+
+// TestInvoiceWorkflow asserts the basic process of inserting, fetching, and
+// updating an invoice. We assert that the flow is successful using when
+// querying with various combinations of payment hash and payment address.
 func TestInvoiceWorkflow(t *testing.T) {
 	t.Parallel()
 
+	for _, test := range invWorkflowTests {
+		test := test
+		t.Run(test.name, func(t *testing.T) {
+			testInvoiceWorkflow(t, test)
+		})
+	}
+}
+
+func testInvoiceWorkflow(t *testing.T, test invWorkflowTest) {
 	db, cleanUp, err := makeTestDB()
 	defer cleanUp()
 	if err != nil {
@@ -102,31 +142,45 @@ func TestInvoiceWorkflow(t *testing.T) {
 
 	// Create a fake invoice which we'll use several times in the tests
 	// below.
-	fakeInvoice := &Invoice{
-		CreationDate: testNow,
-		Htlcs:        map[CircuitKey]*InvoiceHTLC{},
+	fakeInvoice, err := randInvoice(10000)
+	if err != nil {
+		t.Fatalf("unable to create invoice: %v", err)
 	}
-	fakeInvoice.Memo = []byte("memo")
-	fakeInvoice.PaymentRequest = []byte("")
-	copy(fakeInvoice.Terms.PaymentPreimage[:], rev[:])
-	fakeInvoice.Terms.Value = lnwire.NewMSatFromSatoshis(10000)
-	fakeInvoice.Terms.Features = emptyFeatures
+	invPayHash := fakeInvoice.Terms.PaymentPreimage.Hash()
 
-	paymentHash := fakeInvoice.Terms.PaymentPreimage.Hash()
+	// Select the payment hash and payment address we will use to lookup or
+	// update the invoice for the remainder of the test.
+	var (
+		payHash lntypes.Hash
+		payAddr *[32]byte
+		ref     InvoiceRef
+	)
+	switch {
+	case test.queryPayHash && test.queryPayAddr:
+		payHash = invPayHash
+		payAddr = &fakeInvoice.Terms.PaymentAddr
+		ref = InvoiceRefByHashAndAddr(payHash, *payAddr)
+	case test.queryPayHash:
+		payHash = invPayHash
+		ref = InvoiceRefByHash(payHash)
+	}
 
 	// Add the invoice to the database, this should succeed as there aren't
 	// any existing invoices within the database with the same payment
 	// hash.
-	if _, err := db.AddInvoice(fakeInvoice, paymentHash); err != nil {
+	if _, err := db.AddInvoice(fakeInvoice, invPayHash); err != nil {
 		t.Fatalf("unable to find invoice: %v", err)
 	}
 
 	// Attempt to retrieve the invoice which was just added to the
 	// database. It should be found, and the invoice returned should be
 	// identical to the one created above.
-	dbInvoice, err := db.LookupInvoice(paymentHash)
-	if err != nil {
-		t.Fatalf("unable to find invoice: %v", err)
+	dbInvoice, err := db.LookupInvoice(ref)
+	if !test.queryPayAddr && !test.queryPayHash {
+		if err != ErrInvoiceNotFound {
+			t.Fatalf("invoice should not exist: %v", err)
+		}
+		return
 	}
 	if !reflect.DeepEqual(*fakeInvoice, dbInvoice) {
 		t.Fatalf("invoice fetched from db doesn't match original %v vs %v",
@@ -145,11 +199,11 @@ func TestInvoiceWorkflow(t *testing.T) {
 	// now have the settled bit toggle to true and a non-default
 	// SettledDate
 	payAmt := fakeInvoice.Terms.Value * 2
-	_, err = db.UpdateInvoice(paymentHash, getUpdateInvoice(payAmt))
+	_, err = db.UpdateInvoice(ref, getUpdateInvoice(payAmt))
 	if err != nil {
 		t.Fatalf("unable to settle invoice: %v", err)
 	}
-	dbInvoice2, err := db.LookupInvoice(paymentHash)
+	dbInvoice2, err := db.LookupInvoice(ref)
 	if err != nil {
 		t.Fatalf("unable to fetch invoice: %v", err)
 	}
@@ -173,7 +227,7 @@ func TestInvoiceWorkflow(t *testing.T) {
 
 	// Attempt to insert generated above again, this should fail as
 	// duplicates are rejected by the processing logic.
-	if _, err := db.AddInvoice(fakeInvoice, paymentHash); err != ErrDuplicateInvoice {
+	if _, err := db.AddInvoice(fakeInvoice, payHash); err != ErrDuplicateInvoice {
 		t.Fatalf("invoice insertion should fail due to duplication, "+
 			"instead %v", err)
 	}
@@ -181,7 +235,9 @@ func TestInvoiceWorkflow(t *testing.T) {
 	// Attempt to look up a non-existent invoice, this should also fail but
 	// with a "not found" error.
 	var fakeHash [32]byte
-	if _, err := db.LookupInvoice(fakeHash); err != ErrInvoiceNotFound {
+	fakeRef := InvoiceRefByHash(fakeHash)
+	_, err = db.LookupInvoice(fakeRef)
+	if err != ErrInvoiceNotFound {
 		t.Fatalf("lookup should have failed, instead %v", err)
 	}
 
@@ -229,6 +285,70 @@ func TestInvoiceWorkflow(t *testing.T) {
 	}
 }
 
+// TestAddDuplicatePayAddr asserts that the payment addresses of inserted
+// invoices are unique.
+func TestAddDuplicatePayAddr(t *testing.T) {
+	db, cleanUp, err := makeTestDB()
+	defer cleanUp()
+	assert.Nil(t, err)
+
+	// Create two invoices with the same payment addr.
+	invoice1, err := randInvoice(1000)
+	assert.Nil(t, err)
+
+	invoice2, err := randInvoice(20000)
+	assert.Nil(t, err)
+	invoice2.Terms.PaymentAddr = invoice1.Terms.PaymentAddr
+
+	// First insert should succeed.
+	inv1Hash := invoice1.Terms.PaymentPreimage.Hash()
+	_, err = db.AddInvoice(invoice1, inv1Hash)
+	assert.Nil(t, err)
+
+	// Second insert should fail with duplicate payment addr.
+	inv2Hash := invoice2.Terms.PaymentPreimage.Hash()
+	_, err = db.AddInvoice(invoice2, inv2Hash)
+	assert.Equal(t, ErrDuplicatePayAddr, err)
+}
+
+// TestInvRefEquivocation asserts that retrieving or updating an invoice using
+// an equivocating InvoiceRef results in ErrInvRefEquivocation.
+func TestInvRefEquivocation(t *testing.T) {
+	db, cleanUp, err := makeTestDB()
+	defer cleanUp()
+	assert.Nil(t, err)
+
+	// Add two random invoices.
+	invoice1, err := randInvoice(1000)
+	assert.Nil(t, err)
+
+	inv1Hash := invoice1.Terms.PaymentPreimage.Hash()
+	_, err = db.AddInvoice(invoice1, inv1Hash)
+	assert.Nil(t, err)
+
+	invoice2, err := randInvoice(2000)
+	assert.Nil(t, err)
+
+	inv2Hash := invoice2.Terms.PaymentPreimage.Hash()
+	_, err = db.AddInvoice(invoice2, inv2Hash)
+	assert.Nil(t, err)
+
+	// Now, query using invoice 1's payment address, but invoice 2's payment
+	// hash. We expect an error since the invref points to multiple
+	// invoices.
+	ref := InvoiceRefByHashAndAddr(inv2Hash, invoice1.Terms.PaymentAddr)
+	_, err = db.LookupInvoice(ref)
+	assert.Equal(t, ErrInvRefEquivocation, err)
+
+	// The same error should be returned when updating an equivocating
+	// reference.
+	nop := func(_ *Invoice) (*InvoiceUpdateDesc, error) {
+		return nil, nil
+	}
+	_, err = db.UpdateInvoice(ref, nop)
+	assert.Equal(t, ErrInvRefEquivocation, err)
+}
+
 // TestInvoiceCancelSingleHtlc tests that a single htlc can be canceled on the
 // invoice.
 func TestInvoiceCancelSingleHtlc(t *testing.T) {
@@ -257,7 +377,9 @@ func TestInvoiceCancelSingleHtlc(t *testing.T) {
 		Amt:           500,
 		CustomRecords: make(record.CustomSet),
 	}
-	invoice, err := db.UpdateInvoice(paymentHash,
+
+	ref := InvoiceRefByHash(paymentHash)
+	invoice, err := db.UpdateInvoice(ref,
 		func(invoice *Invoice) (*InvoiceUpdateDesc, error) {
 			return &InvoiceUpdateDesc{
 				AddHtlcs: map[CircuitKey]*HtlcAcceptDesc{
@@ -276,13 +398,14 @@ func TestInvoiceCancelSingleHtlc(t *testing.T) {
 	}
 
 	// Cancel the htlc again.
-	invoice, err = db.UpdateInvoice(paymentHash, func(invoice *Invoice) (*InvoiceUpdateDesc, error) {
-		return &InvoiceUpdateDesc{
-			CancelHtlcs: map[CircuitKey]struct{}{
-				key: {},
-			},
-		}, nil
-	})
+	invoice, err = db.UpdateInvoice(ref,
+		func(invoice *Invoice) (*InvoiceUpdateDesc, error) {
+			return &InvoiceUpdateDesc{
+				CancelHtlcs: map[CircuitKey]struct{}{
+					key: {},
+				},
+			}, nil
+		})
 	if err != nil {
 		t.Fatalf("unable to cancel htlc: %v", err)
 	}
@@ -387,8 +510,9 @@ func TestInvoiceAddTimeSeries(t *testing.T) {
 
 		paymentHash := invoice.Terms.PaymentPreimage.Hash()
 
+		ref := InvoiceRefByHash(paymentHash)
 		_, err := db.UpdateInvoice(
-			paymentHash, getUpdateInvoice(invoice.Terms.Value),
+			ref, getUpdateInvoice(invoice.Terms.Value),
 		)
 		if err != nil {
 			t.Fatalf("unable to settle invoice: %v", err)
@@ -577,9 +701,8 @@ func TestDuplicateSettleInvoice(t *testing.T) {
 	}
 
 	// With the invoice in the DB, we'll now attempt to settle the invoice.
-	dbInvoice, err := db.UpdateInvoice(
-		payHash, getUpdateInvoice(amt),
-	)
+	ref := InvoiceRefByHash(payHash)
+	dbInvoice, err := db.UpdateInvoice(ref, getUpdateInvoice(amt))
 	if err != nil {
 		t.Fatalf("unable to settle invoice: %v", err)
 	}
@@ -608,9 +731,7 @@ func TestDuplicateSettleInvoice(t *testing.T) {
 
 	// If we try to settle the invoice again, then we should get the very
 	// same invoice back, but with an error this time.
-	dbInvoice, err = db.UpdateInvoice(
-		payHash, getUpdateInvoice(amt),
-	)
+	dbInvoice, err = db.UpdateInvoice(ref, getUpdateInvoice(amt))
 	if err != ErrInvoiceAlreadySettled {
 		t.Fatalf("expected ErrInvoiceAlreadySettled")
 	}
@@ -660,9 +781,8 @@ func TestQueryInvoices(t *testing.T) {
 
 		// We'll only settle half of all invoices created.
 		if i%2 == 0 {
-			_, err := db.UpdateInvoice(
-				paymentHash, getUpdateInvoice(amt),
-			)
+			ref := InvoiceRefByHash(paymentHash)
+			_, err := db.UpdateInvoice(ref, getUpdateInvoice(amt))
 			if err != nil {
 				t.Fatalf("unable to settle invoice: %v", err)
 			}
@@ -958,7 +1078,8 @@ func TestCustomRecords(t *testing.T) {
 		100001: []byte{1, 2},
 	}
 
-	_, err = db.UpdateInvoice(paymentHash,
+	ref := InvoiceRefByHash(paymentHash)
+	_, err = db.UpdateInvoice(ref,
 		func(invoice *Invoice) (*InvoiceUpdateDesc, error) {
 			return &InvoiceUpdateDesc{
 				AddHtlcs: map[CircuitKey]*HtlcAcceptDesc{
@@ -976,7 +1097,7 @@ func TestCustomRecords(t *testing.T) {
 
 	// Retrieve the invoice from that database and verify that the custom
 	// records are present.
-	dbInvoice, err := db.LookupInvoice(paymentHash)
+	dbInvoice, err := db.LookupInvoice(ref)
 	if err != nil {
 		t.Fatalf("unable to lookup invoice: %v", err)
 	}
@@ -988,3 +1109,22 @@ func TestCustomRecords(t *testing.T) {
 		t.Fatalf("invalid custom records")
 	}
 }
+
+// TestInvoiceRef asserts that the proper identifiers are returned from an
+// InvoiceRef depending on the constructor used.
+func TestInvoiceRef(t *testing.T) {
+	payHash := lntypes.Hash{0x01}
+	payAddr := [32]byte{0x02}
+
+	// An InvoiceRef by hash should return the provided hash and a nil
+	// payment addr.
+	refByHash := InvoiceRefByHash(payHash)
+	assert.Equal(t, payHash, refByHash.PayHash())
+	assert.Equal(t, (*[32]byte)(nil), refByHash.PayAddr())
+
+	// An InvoiceRef by hash and addr should return the payment hash and
+	// payment addr passed to the constructor.
+	refByHashAndAddr := InvoiceRefByHashAndAddr(payHash, payAddr)
+	assert.Equal(t, payHash, refByHashAndAddr.PayHash())
+	assert.Equal(t, &payAddr, refByHashAndAddr.PayAddr())
+}

channeldb/invoices.go

@@ -37,6 +37,16 @@ var (
 	// maps: payHash => invoiceKey
 	invoiceIndexBucket = []byte("paymenthashes")
 
+	// payAddrIndexBucket is the name of the top-level bucket that maps
+	// payment addresses to their invoice number. This can be used
+	// to efficiently query or update non-legacy invoices. Note that legacy
+	// invoices will not be included in this index since they all have the
+	// same, all-zero payment address, however all newly generated invoices
+	// will end up in this index.
+	//
+	// maps: payAddr => invoiceKey
+	payAddrIndexBucket = []byte("pay-addr-index")
+
 	// numInvoicesKey is the name of key which houses the auto-incrementing
 	// invoice ID which is essentially used as a primary key. With each
 	// invoice inserted, the primary key is incremented by one. This key is
@@ -142,6 +152,69 @@ const (
 	amtPaidType     tlv.Type = 13
 )
 
+// InvoiceRef is a composite identifier for invoices. Invoices can be referenced
+// by various combinations of payment hash and payment addr, in certain contexts
+// only some of these are known. An InvoiceRef and its constructors thus
+// encapsulate the valid combinations of query parameters that can be supplied
+// to LookupInvoice and UpdateInvoice.
+type InvoiceRef struct {
+	// payHash is the payment hash of the target invoice. All invoices are
+	// currently indexed by payment hash. This value will be used as a
+	// fallback when no payment address is known.
+	payHash lntypes.Hash
+
+	// payAddr is the payment addr of the target invoice. Newer invoices
+	// (0.11 and up) are indexed by payment address in addition to payment
+	// hash, but pre 0.8 invoices do not have one at all. When this value is
+	// known it will be used as the primary identifier, falling back to
+	// payHash if no value is known.
+	payAddr *[32]byte
+}
+
+// InvoiceRefByHash creates an InvoiceRef that queries for an invoice only by
+// its payment hash.
+func InvoiceRefByHash(payHash lntypes.Hash) InvoiceRef {
+	return InvoiceRef{
+		payHash: payHash,
+	}
+}
+
+// InvoiceRefByHashAndAddr creates an InvoiceRef that first queries for an
+// invoice by the provided payment address, falling back to the payment hash if
+// the payment address is unknown.
+func InvoiceRefByHashAndAddr(payHash lntypes.Hash,
+	payAddr [32]byte) InvoiceRef {
+
+	return InvoiceRef{
+		payHash: payHash,
+		payAddr: &payAddr,
+	}
+}
+
+// PayHash returns the target invoice's payment hash.
+func (r InvoiceRef) PayHash() lntypes.Hash {
+	return r.payHash
+}
+
+// PayAddr returns the optional payment address of the target invoice.
+//
+// NOTE: This value may be nil.
+func (r InvoiceRef) PayAddr() *[32]byte {
+	if r.payAddr != nil {
+		addr := *r.payAddr
+		return &addr
+	}
+	return nil
+}
+
+// String returns a human-readable representation of an InvoiceRef.
+func (r InvoiceRef) String() string {
+	if r.payAddr != nil {
+		return fmt.Sprintf("(pay_hash=%v, pay_addr=%x)", r.payHash, *r.payAddr)
+	}
+	return fmt.Sprintf("(pay_hash=%v)", r.payHash)
+}
+
 // ContractState describes the state the invoice is in.
 type ContractState uint8
 
@@ -432,6 +505,11 @@ func (d *DB) AddInvoice(newInvoice *Invoice, paymentHash lntypes.Hash) (
 			return ErrDuplicateInvoice
 		}
 
+		payAddrIndex := tx.ReadWriteBucket(payAddrIndexBucket)
+		if payAddrIndex.Get(newInvoice.Terms.PaymentAddr[:]) != nil {
+			return ErrDuplicatePayAddr
+		}
+
 		// If the current running payment ID counter hasn't yet been
 		// created, then create it now.
 		var invoiceNum uint32
@@ -448,8 +526,8 @@ func (d *DB) AddInvoice(newInvoice *Invoice, paymentHash lntypes.Hash) (
 		}
 
 		newIndex, err := putInvoice(
-			invoices, invoiceIndex, addIndex, newInvoice, invoiceNum,
-			paymentHash,
+			invoices, invoiceIndex, payAddrIndex, addIndex,
+			newInvoice, invoiceNum, paymentHash,
 		)
 		if err != nil {
 			return err
@@ -533,7 +611,7 @@ func (d *DB) InvoicesAddedSince(sinceAddIndex uint64) ([]Invoice, error) {
 // full invoice is returned. Before setting the incoming HTLC, the values
 // SHOULD be checked to ensure the payer meets the agreed upon contractual
 // terms of the payment.
-func (d *DB) LookupInvoice(paymentHash [32]byte) (Invoice, error) {
+func (d *DB) LookupInvoice(ref InvoiceRef) (Invoice, error) {
 	var invoice Invoice
 	err := kvdb.View(d, func(tx kvdb.RTx) error {
 		invoices := tx.ReadBucket(invoiceBucket)
@@ -544,16 +622,19 @@ func (d *DB) LookupInvoice(paymentHash [32]byte) (Invoice, error) {
 		if invoiceIndex == nil {
 			return ErrNoInvoicesCreated
 		}
+		payAddrIndex := tx.ReadBucket(payAddrIndexBucket)
 
-		// Check the invoice index to see if an invoice paying to this
-		// hash exists within the DB.
-		invoiceNum := invoiceIndex.Get(paymentHash[:])
-		if invoiceNum == nil {
-			return ErrInvoiceNotFound
+		// Retrieve the invoice number for this invoice using the
+		// provided invoice reference.
+		invoiceNum, err := fetchInvoiceNumByRef(
+			invoiceIndex, payAddrIndex, ref,
+		)
+		if err != nil {
+			return err
 		}
 
-		// An invoice matching the payment hash has been found, so
-		// retrieve the record of the invoice itself.
+		// An invoice was found, retrieve the remainder of the invoice
+		// body.
 		i, err := fetchInvoice(invoiceNum, invoices)
 		if err != nil {
 			return err
@@ -569,6 +650,47 @@ func (d *DB) LookupInvoice(paymentHash [32]byte) (Invoice, error) {
 	return invoice, nil
 }
 
+// fetchInvoiceNumByRef retrieve the invoice number for the provided invoice
+// reference. The payment address will be treated as the primary key, falling
+// back to the payment hash if nothing is found for the payment address. An
+// error is returned if the invoice is not found.
+func fetchInvoiceNumByRef(invoiceIndex, payAddrIndex kvdb.ReadBucket,
+	ref InvoiceRef) ([]byte, error) {
+
+	payHash := ref.PayHash()
+	payAddr := ref.PayAddr()
+
+	var (
+		invoiceNumByHash = invoiceIndex.Get(payHash[:])
+		invoiceNumByAddr []byte
+	)
+	if payAddr != nil {
+		invoiceNumByAddr = payAddrIndex.Get(payAddr[:])
+	}
+
+	switch {
+
+	// If payment address and payment hash both reference an existing
+	// invoice, ensure they reference the _same_ invoice.
+	case invoiceNumByAddr != nil && invoiceNumByHash != nil:
+		if !bytes.Equal(invoiceNumByAddr, invoiceNumByHash) {
+			return nil, ErrInvRefEquivocation
+		}
+
+		return invoiceNumByAddr, nil
+
+	// If we were only able to reference the invoice by hash, return the
+	// corresponding invoice number. This can happen when no payment address
+	// was provided, or if it didn't match anything in our records.
+	case invoiceNumByHash != nil:
+		return invoiceNumByHash, nil
+
+	// Otherwise we don't know of the target invoice.
+	default:
+		return nil, ErrInvoiceNotFound
+	}
+}
+
 // InvoiceWithPaymentHash is used to store an invoice and its corresponding
 // payment hash. This struct is only used to store results of
 // ChannelDB.FetchAllInvoicesWithPaymentHash() call.
@@ -819,7 +941,7 @@ func (d *DB) QueryInvoices(q InvoiceQuery) (InvoiceSlice, error) {
 // The update is performed inside the same database transaction that fetches the
 // invoice and is therefore atomic. The fields to update are controlled by the
 // supplied callback.
-func (d *DB) UpdateInvoice(paymentHash lntypes.Hash,
+func (d *DB) UpdateInvoice(ref InvoiceRef,
 	callback InvoiceUpdateCallback) (*Invoice, error) {
 
 	var updatedInvoice *Invoice
@@ -840,16 +962,20 @@ func (d *DB) UpdateInvoice(paymentHash lntypes.Hash,
 		if err != nil {
 			return err
 		}
+		payAddrIndex := tx.ReadBucket(payAddrIndexBucket)
+
+		// Retrieve the invoice number for this invoice using the
+		// provided invoice reference.
+		invoiceNum, err := fetchInvoiceNumByRef(
+			invoiceIndex, payAddrIndex, ref,
+		)
+		if err != nil {
+			return err
 
-		// Check the invoice index to see if an invoice paying to this
-		// hash exists within the DB.
-		invoiceNum := invoiceIndex.Get(paymentHash[:])
-		if invoiceNum == nil {
-			return ErrInvoiceNotFound
 		}
-
+		payHash := ref.PayHash()
 		updatedInvoice, err = d.updateInvoice(
-			paymentHash, invoices, settleIndex, invoiceNum,
+			payHash, invoices, settleIndex, invoiceNum,
 			callback,
 		)
 
@@ -920,7 +1046,7 @@ func (d *DB) InvoicesSettledSince(sinceSettleIndex uint64) ([]Invoice, error) {
 	return settledInvoices, nil
 }
 
-func putInvoice(invoices, invoiceIndex, addIndex kvdb.RwBucket,
+func putInvoice(invoices, invoiceIndex, payAddrIndex, addIndex kvdb.RwBucket,
 	i *Invoice, invoiceNum uint32, paymentHash lntypes.Hash) (
 	uint64, error) {
 
@@ -945,6 +1071,10 @@ func putInvoice(invoices, invoiceIndex, addIndex kvdb.RwBucket,
 	if err != nil {
 		return 0, err
 	}
+	err = payAddrIndex.Put(i.Terms.PaymentAddr[:], invoiceKey[:])
+	if err != nil {
+		return 0, err
+	}
 
 	// Next, we'll obtain the next add invoice index (sequence
 	// number), so we can properly place this invoice within this

channeldb/log.go

@@ -3,6 +3,7 @@ package channeldb
 import (
 	"github.com/btcsuite/btclog"
 	"github.com/lightningnetwork/lnd/build"
+	mig "github.com/lightningnetwork/lnd/channeldb/migration"
 	"github.com/lightningnetwork/lnd/channeldb/migration12"
 	"github.com/lightningnetwork/lnd/channeldb/migration13"
 	"github.com/lightningnetwork/lnd/channeldb/migration_01_to_11"
@@ -28,6 +29,7 @@ func DisableLog() {
 // using btclog.
 func UseLogger(logger btclog.Logger) {
 	log = logger
+	mig.UseLogger(logger)
 	migration_01_to_11.UseLogger(logger)
 	migration12.UseLogger(logger)
 	migration13.UseLogger(logger)

channeldb/migration/create_tlb.go

@@ -0,0 +1,27 @@
+package migration
+
+import (
+	"fmt"
+
+	"github.com/lightningnetwork/lnd/channeldb/kvdb"
+)
+
+// CreateTLB creates a new top-level bucket with the passed bucket identifier.
+func CreateTLB(bucket []byte) func(kvdb.RwTx) error {
+	return func(tx kvdb.RwTx) error {
+		log.Infof("Creating top-level bucket: \"%s\" ...", bucket)
+
+		if tx.ReadBucket(bucket) != nil {
+			return fmt.Errorf("top-level bucket \"%s\" "+
+				"already exists", bucket)
+		}
+
+		_, err := tx.CreateTopLevelBucket(bucket)
+		if err != nil {
+			return err
+		}
+
+		log.Infof("Created top-level bucket: \"%s\"", bucket)
+		return nil
+	}
+}

channeldb/migration/create_tlb_test.go

@@ -0,0 +1,57 @@
+package migration_test
+
+import (
+	"fmt"
+	"testing"
+
+	"github.com/lightningnetwork/lnd/channeldb/kvdb"
+	"github.com/lightningnetwork/lnd/channeldb/migration"
+	"github.com/lightningnetwork/lnd/channeldb/migtest"
+)
+
+// TestCreateTLB asserts that a CreateTLB properly initializes a new top-level
+// bucket, and that it succeeds even if the bucket already exists. It would
+// probably be better if the latter failed, but the kvdb abstraction doesn't
+// support this.
+func TestCreateTLB(t *testing.T) {
+	newBucket := []byte("hello")
+
+	tests := []struct {
+		name            string
+		beforeMigration func(kvdb.RwTx) error
+		shouldFail      bool
+	}{
+		{
+			name: "already exists",
+			beforeMigration: func(tx kvdb.RwTx) error {
+				_, err := tx.CreateTopLevelBucket(newBucket)
+				return err
+			},
+			shouldFail: true,
+		},
+		{
+			name:            "does not exist",
+			beforeMigration: func(_ kvdb.RwTx) error { return nil },
+			shouldFail:      false,
+		},
+	}
+
+	for _, test := range tests {
+		test := test
+		t.Run(test.name, func(t *testing.T) {
+			migtest.ApplyMigration(
+				t,
+				test.beforeMigration,
+				func(tx kvdb.RwTx) error {
+					if tx.ReadBucket(newBucket) != nil {
+						return nil
+					}
+					return fmt.Errorf("bucket \"%s\" not "+
+						"created", newBucket)
+				},
+				migration.CreateTLB(newBucket),
+				test.shouldFail,
+			)
+		})
+	}
+}

channeldb/migration/log.go

@@ -0,0 +1,12 @@
+package migration
+
+import "github.com/btcsuite/btclog"
+
+// log is a logger that is initialized as disabled.  This means the package will
+// not perform any logging by default until a logger is set.
+var log = btclog.Disabled
+
+// UseLogger uses a specified Logger to output package logging info.
+func UseLogger(logger btclog.Logger) {
+	log = logger
+}

channeldb/migtest/migtest.go

@@ -74,7 +74,7 @@ func ApplyMigration(t *testing.T,
 	// Apply migration.
 	err = kvdb.Update(cdb, migrationFunc)
 	if err != nil {
-		t.Fatal(err)
+		t.Logf("migration error: %v", err)
 	}
 }