[tor] Add ability to encrypt the Tor private key on disk

chanbackup/backupfile_test.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 	"testing"
 
+	"github.com/lightningnetwork/lnd/lnencrypt"
 	"github.com/stretchr/testify/require"
 )
 
@@ -184,7 +185,7 @@ func assertMultiEqual(t *testing.T, a, b *Multi) {
 func TestExtractMulti(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	// First, as prep, we'll create a single chan backup, then pack that
 	// fully into a multi backup.

chanbackup/multi.go

@@ -6,6 +6,7 @@ import (
 	"io"
 
 	"github.com/lightningnetwork/lnd/keychain"
+	"github.com/lightningnetwork/lnd/lnencrypt"
 	"github.com/lightningnetwork/lnd/lnwire"
 )
 
@@ -89,7 +90,12 @@ func (m Multi) PackToWriter(w io.Writer, keyRing keychain.KeyRing) error {
 
 	// With the plaintext multi backup assembled, we'll now encrypt it
 	// directly to the passed writer.
-	return encryptPayloadToWriter(multiBackupBuffer, w, keyRing)
+	e, err := lnencrypt.KeyRingEncrypter(keyRing)
+	if err != nil {
+		return fmt.Errorf("unable to generate encrypt key %v", err)
+	}
+
+	return e.EncryptPayloadToWriter(multiBackupBuffer.Bytes(), w)
 }
 
 // UnpackFromReader attempts to unpack (decrypt+deserialize) a packed
@@ -99,7 +105,11 @@ func (m *Multi) UnpackFromReader(r io.Reader, keyRing keychain.KeyRing) error {
 	// We'll attempt to read the entire packed backup, and also decrypt it
 	// using the passed key ring which is expected to be able to derive the
 	// encryption keys.
-	plaintextBackup, err := decryptPayloadFromReader(r, keyRing)
+	e, err := lnencrypt.KeyRingEncrypter(keyRing)
+	if err != nil {
+		return fmt.Errorf("unable to generate encrypt key %v", err)
+	}
+	plaintextBackup, err := e.DecryptPayloadFromReader(r)
 	if err != nil {
 		return err
 	}

chanbackup/multi_test.go

@@ -5,6 +5,7 @@ import (
 	"net"
 	"testing"
 
+	"github.com/lightningnetwork/lnd/lnencrypt"
 	"github.com/stretchr/testify/require"
 )
 
@@ -27,7 +28,7 @@ func TestMultiPackUnpack(t *testing.T) {
 		multi.StaticBackups = append(multi.StaticBackups, single)
 	}
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	versionTestCases := []struct {
 		// version is the pack/unpack version that we should use to
@@ -93,14 +94,17 @@ func TestMultiPackUnpack(t *testing.T) {
 				)
 			}
 
+			encrypter, err := lnencrypt.KeyRingEncrypter(keyRing)
+			require.NoError(t, err)
+
 			// Next, we'll make a fake packed multi, it'll have an
 			// unknown version relative to what's implemented atm.
 			var fakePackedMulti bytes.Buffer
 			fakeRawMulti := bytes.NewBuffer(
 				bytes.Repeat([]byte{99}, 20),
 			)
-			err := encryptPayloadToWriter(
-				*fakeRawMulti, &fakePackedMulti, keyRing,
+			err = encrypter.EncryptPayloadToWriter(
+				fakeRawMulti.Bytes(), &fakePackedMulti,
 			)
 			if err != nil {
 				t.Fatalf("unable to pack fake multi; %v", err)
@@ -124,7 +128,7 @@ func TestMultiPackUnpack(t *testing.T) {
 func TestPackedMultiUnpack(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	// First, we'll make a new unpacked multi with a random channel.
 	testChannel, err := genRandomOpenChannelShell()

chanbackup/pubsub_test.go

@@ -7,6 +7,7 @@ import (
 
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/keychain"
+	"github.com/lightningnetwork/lnd/lnencrypt"
 	"github.com/stretchr/testify/require"
 )
 
@@ -80,7 +81,7 @@ func (m *mockChannelNotifier) SubscribeChans(chans map[wire.OutPoint]struct{}) (
 func TestNewSubSwapperSubscribeFail(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	var swapper mockSwapper
 	chanNotifier := mockChannelNotifier{
@@ -152,7 +153,7 @@ func assertExpectedBackupSwap(t *testing.T, swapper *mockSwapper,
 func TestSubSwapperIdempotentStartStop(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	var chanNotifier mockChannelNotifier
 
@@ -181,7 +182,7 @@ func TestSubSwapperIdempotentStartStop(t *testing.T) {
 func TestSubSwapperUpdater(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 	chanNotifier := newMockChannelNotifier()
 	swapper := newMockSwapper(keyRing)
 

chanbackup/recover_test.go

@@ -7,6 +7,7 @@ import (
 	"testing"
 
 	"github.com/btcsuite/btcd/btcec/v2"
+	"github.com/lightningnetwork/lnd/lnencrypt"
 	"github.com/stretchr/testify/require"
 )
 
@@ -49,7 +50,7 @@ func (m *mockPeerConnector) ConnectPeer(node *btcec.PublicKey,
 func TestUnpackAndRecoverSingles(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	// First, we'll create a number of single chan backups that we'll
 	// shortly back to so we can begin our recovery attempt.
@@ -123,7 +124,7 @@ func TestUnpackAndRecoverSingles(t *testing.T) {
 	}
 
 	// If we modify the keyRing, then unpacking should fail.
-	keyRing.fail = true
+	keyRing.Fail = true
 	err = UnpackAndRecoverSingles(
 		packedBackups, keyRing, &chanRestorer, &peerConnector,
 	)
@@ -139,7 +140,7 @@ func TestUnpackAndRecoverSingles(t *testing.T) {
 func TestUnpackAndRecoverMulti(t *testing.T) {
 	t.Parallel()
 
-	keyRing := &mockKeyRing{}
+	keyRing := &lnencrypt.MockKeyRing{}
 
 	// First, we'll create a number of single chan backups that we'll
 	// shortly back to so we can begin our recovery attempt.
@@ -217,7 +218,7 @@ func TestUnpackAndRecoverMulti(t *testing.T) {
 	}
 
 	// If we modify the keyRing, then unpacking should fail.
-	keyRing.fail = true
+	keyRing.Fail = true
 	err = UnpackAndRecoverMulti(
 		packedMulti, keyRing, &chanRestorer, &peerConnector,
 	)

chanbackup/single.go

@@ -12,6 +12,7 @@ import (
 	"github.com/btcsuite/btcd/wire"
 	"github.com/lightningnetwork/lnd/channeldb"
 	"github.com/lightningnetwork/lnd/keychain"
+	"github.com/lightningnetwork/lnd/lnencrypt"
 	"github.com/lightningnetwork/lnd/lnwire"
 )
 
@@ -333,10 +334,10 @@ func (s *Single) Serialize(w io.Writer) error {
 // global counter to use as a sequence number for nonces, and want to ensure
 // that we're able to decrypt these blobs without any additional context. We
 // derive the key that we use for encryption via a SHA2 operation of the with
-// the golden keychain.KeyFamilyStaticBackup base encryption key.  We then take
-// the serialized resulting shared secret point, and hash it using sha256 to
-// obtain the key that we'll use for encryption. When using the AEAD, we pass
-// the nonce as associated data such that we'll be able to package the two
+// the golden keychain.KeyFamilyBaseEncryption base encryption key.  We then
+// take the serialized resulting shared secret point, and hash it using sha256
+// to obtain the key that we'll use for encryption. When using the AEAD, we
+// pass the nonce as associated data such that we'll be able to package the two
 // together for storage. Before writing out the encrypted payload, we prepend
 // the nonce to the final blob.
 func (s *Single) PackToWriter(w io.Writer, keyRing keychain.KeyRing) error {
@@ -351,7 +352,11 @@ func (s *Single) PackToWriter(w io.Writer, keyRing keychain.KeyRing) error {
 	// Finally, we'll encrypt the raw serialized SCB (using the nonce as
 	// associated data), and write out the ciphertext prepend with the
 	// nonce that we used to the passed io.Reader.
-	return encryptPayloadToWriter(rawBytes, w, keyRing)
+	e, err := lnencrypt.KeyRingEncrypter(keyRing)
+	if err != nil {
+		return fmt.Errorf("unable to generate encrypt key %v", err)
+	}
+	return e.EncryptPayloadToWriter(rawBytes.Bytes(), w)
 }
 
 // readLocalKeyDesc reads a KeyDescriptor encoded within an unpacked Single.
@@ -528,7 +533,11 @@ func (s *Single) Deserialize(r io.Reader) error {
 // payload for whatever reason (wrong key, wrong nonce, etc), then this method
 // will return an error.
 func (s *Single) UnpackFromReader(r io.Reader, keyRing keychain.KeyRing) error {
-	plaintext, err := decryptPayloadFromReader(r, keyRing)
+	e, err := lnencrypt.KeyRingEncrypter(keyRing)
+	if err != nil {
+		return fmt.Errorf("unable to generate key decrypter %v", err)
+	}
+	plaintext, err := e.DecryptPayloadFromReader(r)
 	if err != nil {
 		return err
 	}