cnct+lnwl+hswc: use lntypes.Preimage for witness beacon

lnwallet/channel.go

@@ -5577,12 +5577,12 @@ func extractHtlcResolutions(feePerKw SatPerKWeight, ourCommit bool,
 			// We'll now query the preimage cache for the preimage
 			// for this HTLC. If it's present then we can fully
 			// populate this resolution.
-			preimage, _ := pCache.LookupPreimage(htlc.RHash[:])
+			preimage, _ := pCache.LookupPreimage(htlc.RHash)
 
 			// Otherwise, we'll create an incoming HTLC resolution
 			// as we can satisfy the contract.
 			var pre [32]byte
-			copy(pre[:], preimage)
+			copy(pre[:], preimage[:])
 			ihr, err := newIncomingHtlcResolution(
 				signer, localChanCfg, commitHash, &htlc, keyRing,
 				feePerKw, dustLimit, uint32(csvDelay), ourCommit,

lnwallet/channel_test.go

@@ -19,6 +19,7 @@ import (
 	"github.com/lightningnetwork/lnd/chainntnfs"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/input"
+	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/lightningnetwork/lnd/lnwire"
 )
 
@@ -584,7 +585,7 @@ func TestForceClose(t *testing.T) {
 
 	// Before we force close Alice's channel, we'll add the pre-image of
 	// Bob's HTLC to her preimage cache.
-	aliceChannel.pCache.AddPreimages(preimageBob[:])
+	aliceChannel.pCache.AddPreimages(lntypes.Preimage(preimageBob))
 
 	// With the cache populated, we'll now attempt the force close
 	// initiated by Alice.
@@ -4953,7 +4954,7 @@ func TestChannelUnilateralCloseHtlcResolution(t *testing.T) {
 	// Now that Bob has force closed, we'll modify Alice's pre image cache
 	// such that she now gains the ability to also settle the incoming HTLC
 	// from Bob.
-	aliceChannel.pCache.AddPreimages(preimageBob[:])
+	aliceChannel.pCache.AddPreimages(lntypes.Preimage(preimageBob))
 
 	// We'll then use Bob's transaction to trigger a spend notification for
 	// Alice.

lnwallet/interface.go

@@ -9,6 +9,7 @@ import (
 	"github.com/btcsuite/btcd/chaincfg/chainhash"
 	"github.com/btcsuite/btcd/wire"
 	"github.com/btcsuite/btcutil"
+	"github.com/lightningnetwork/lnd/lntypes"
 )
 
 // AddressType is an enum-like type which denotes the possible address types
@@ -272,15 +273,12 @@ type PreimageCache interface {
 	// LookupPreimage attempts to look up a preimage according to its hash.
 	// If found, the preimage is returned along with true for the second
 	// argument. Otherwise, it'll return false.
-	LookupPreimage(hash []byte) ([]byte, bool)
+	LookupPreimage(hash lntypes.Hash) (lntypes.Preimage, bool)
 
 	// AddPreimages adds a batch of newly discovered preimages to the global
 	// cache, and also signals any subscribers of the newly discovered
 	// witness.
-	//
-	// NOTE: The backing slice of MUST NOT be modified, otherwise the
-	// subscribers may be notified of the incorrect preimages.
-	AddPreimages(preimages ...[]byte) error
+	AddPreimages(preimages ...lntypes.Preimage) error
 }
 
 // WalletDriver represents a "driver" for a particular concrete

lnwallet/test_utils.go

@@ -3,7 +3,6 @@ package lnwallet
 import (
 	"bytes"
 	"crypto/rand"
-	"crypto/sha256"
 	"encoding/binary"
 	"encoding/hex"
 	"io"
@@ -18,6 +17,7 @@ import (
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/input"
 	"github.com/lightningnetwork/lnd/keychain"
+	"github.com/lightningnetwork/lnd/lntypes"
 	"github.com/lightningnetwork/lnd/lnwire"
 	"github.com/lightningnetwork/lnd/shachain"
 )
@@ -301,10 +301,7 @@ func CreateTestChannels() (*LightningChannel, *LightningChannel, func(), error)
 	aliceSigner := &input.MockSigner{Privkeys: aliceKeys}
 	bobSigner := &input.MockSigner{Privkeys: bobKeys}
 
-	pCache := &mockPreimageCache{
-		// hash -> preimage
-		preimageMap: make(map[[32]byte][]byte),
-	}
+	pCache := newMockPreimageCache()
 
 	// TODO(roasbeef): make mock version of pre-image store
 
@@ -389,26 +386,36 @@ func initRevocationWindows(chanA, chanB *LightningChannel) error {
 
 type mockPreimageCache struct {
 	sync.Mutex
-	preimageMap map[[32]byte][]byte
+	preimageMap map[lntypes.Hash]lntypes.Preimage
 }
 
-func (m *mockPreimageCache) LookupPreimage(hash []byte) ([]byte, bool) {
+func newMockPreimageCache() *mockPreimageCache {
+	return &mockPreimageCache{
+		preimageMap: make(map[lntypes.Hash]lntypes.Preimage),
+	}
+}
+
+func (m *mockPreimageCache) LookupPreimage(
+	hash lntypes.Hash) (lntypes.Preimage, bool) {
+
 	m.Lock()
 	defer m.Unlock()
 
-	var h [32]byte
-	copy(h[:], hash)
-
-	p, ok := m.preimageMap[h]
+	p, ok := m.preimageMap[hash]
 	return p, ok
 }
 
-func (m *mockPreimageCache) AddPreimages(preimages ...[]byte) error {
+func (m *mockPreimageCache) AddPreimages(preimages ...lntypes.Preimage) error {
+	preimageCopies := make([]lntypes.Preimage, 0, len(preimages))
+	for _, preimage := range preimages {
+		preimageCopies = append(preimageCopies, preimage)
+	}
+
 	m.Lock()
 	defer m.Unlock()
 
-	for _, preimage := range preimages {
-		m.preimageMap[sha256.Sum256(preimage)] = preimage
+	for _, preimage := range preimageCopies {
+		m.preimageMap[preimage.Hash()] = preimage
 	}
 
 	return nil

lnwallet/transactions_test.go

@@ -780,10 +780,7 @@ func TestCommitmentAndHTLCTransactions(t *testing.T) {
 		},
 	}
 
-	pCache := &mockPreimageCache{
-		// hash -> preimage
-		preimageMap: make(map[[32]byte][]byte),
-	}
+	pCache := newMockPreimageCache()
 
 	for i, test := range testCases {
 		expectedCommitmentTx, err := txFromHex(test.expectedCommitmentTxHex)