watchtower/wtdb/tower_db_test: add mock+bolt iface tests

watchtower/wtdb/tower_db_test.go

@@ -0,0 +1,730 @@
+package wtdb_test
+
+import (
+	"encoding/binary"
+	"io/ioutil"
+	"os"
+	"reflect"
+	"testing"
+
+	"github.com/btcsuite/btcd/chaincfg/chainhash"
+	"github.com/lightningnetwork/lnd/chainntnfs"
+	"github.com/lightningnetwork/lnd/watchtower"
+	"github.com/lightningnetwork/lnd/watchtower/wtdb"
+	"github.com/lightningnetwork/lnd/watchtower/wtmock"
+	"github.com/lightningnetwork/lnd/watchtower/wtpolicy"
+)
+
+// dbInit is a closure used to initialize a watchtower.DB instance and its
+// cleanup function.
+type dbInit func(*testing.T) (watchtower.DB, func())
+
+// towerDBHarness holds the resources required to execute the tower db tests.
+type towerDBHarness struct {
+	t  *testing.T
+	db watchtower.DB
+}
+
+// newTowerDBHarness initializes a fresh test harness for testing watchtower.DB
+// implementations.
+func newTowerDBHarness(t *testing.T, init dbInit) (*towerDBHarness, func()) {
+	db, cleanup := init(t)
+
+	h := &towerDBHarness{
+		t:  t,
+		db: db,
+	}
+
+	return h, cleanup
+}
+
+// insertSession attempts to isnert the passed session and asserts that the
+// error returned matches expErr.
+func (h *towerDBHarness) insertSession(s *wtdb.SessionInfo, expErr error) {
+	h.t.Helper()
+
+	err := h.db.InsertSessionInfo(s)
+	if err != expErr {
+		h.t.Fatalf("expected insert session error: %v, got : %v",
+			expErr, err)
+	}
+}
+
+// getSession retrieves the session identified by id, asserting that the call
+// returns expErr. If successful, the found session is returned.
+func (h *towerDBHarness) getSession(id *wtdb.SessionID,
+	expErr error) *wtdb.SessionInfo {
+
+	h.t.Helper()
+
+	session, err := h.db.GetSessionInfo(id)
+	if err != expErr {
+		h.t.Fatalf("expected get session error: %v, got: %v",
+			expErr, err)
+	}
+
+	return session
+}
+
+// insertUpdate attempts to insert the passed state update and asserts that the
+// error returned matches expErr. If successful, the session's last applied
+// value is returned.
+func (h *towerDBHarness) insertUpdate(s *wtdb.SessionStateUpdate,
+	expErr error) uint16 {
+
+	h.t.Helper()
+
+	lastApplied, err := h.db.InsertStateUpdate(s)
+	if err != expErr {
+		h.t.Fatalf("expected insert update error: %v, got: %v",
+			expErr, err)
+	}
+
+	return lastApplied
+}
+
+// deleteSession attempts to delete the session identified by id and asserts
+// that the error returned from DeleteSession matches the expected error.
+func (h *towerDBHarness) deleteSession(id wtdb.SessionID, expErr error) {
+	h.t.Helper()
+
+	err := h.db.DeleteSession(id)
+	if err != expErr {
+		h.t.Fatalf("expected deletion error: %v, got: %v",
+			expErr, err)
+	}
+}
+
+// queryMatches queries that database for the passed breach hint, returning all
+// matches found.
+func (h *towerDBHarness) queryMatches(hint wtdb.BreachHint) []wtdb.Match {
+	h.t.Helper()
+
+	matches, err := h.db.QueryMatches([]wtdb.BreachHint{hint})
+	if err != nil {
+		h.t.Fatalf("unable to query matches: %v", err)
+	}
+
+	return matches
+}
+
+// hasUpdate queries the database for the passed breach hint, asserting that
+// only one match is present and that the hints indeed match. If successful, the
+// match is returned.
+func (h *towerDBHarness) hasUpdate(hint wtdb.BreachHint) wtdb.Match {
+	h.t.Helper()
+
+	matches := h.queryMatches(hint)
+	if len(matches) != 1 {
+		h.t.Fatalf("expected 1 match, found: %d", len(matches))
+	}
+
+	match := matches[0]
+	if match.Hint != hint {
+		h.t.Fatalf("expected hint: %x, got: %x", hint, match.Hint)
+	}
+
+	return match
+}
+
+// testInsertSession asserts that a session can only be inserted if a session
+// with the same session id does not already exist.
+func testInsertSession(h *towerDBHarness) {
+	var id wtdb.SessionID
+	h.getSession(&id, wtdb.ErrSessionNotFound)
+
+	session := &wtdb.SessionInfo{
+		ID: id,
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 100,
+		},
+		RewardAddress: []byte{0x01, 0x02, 0x03},
+	}
+
+	h.insertSession(session, nil)
+
+	session2 := h.getSession(&id, nil)
+
+	if !reflect.DeepEqual(session, session2) {
+		h.t.Fatalf("expected session: %v, got %v",
+			session, session2)
+	}
+
+	h.insertSession(session, nil)
+
+	// Insert a state update to fully commit the session parameters.
+	update := &wtdb.SessionStateUpdate{
+		ID:     id,
+		SeqNum: 1,
+	}
+	h.insertUpdate(update, nil)
+
+	// Trying to insert a new session under the same ID should fail.
+	h.insertSession(session, wtdb.ErrSessionAlreadyExists)
+}
+
+// testMultipleMatches asserts that if multiple sessions insert state updates
+// with the same breach hint that all will be returned from QueryMatches.
+func testMultipleMatches(h *towerDBHarness) {
+	const numUpdates = 3
+
+	// Create a new session and send updates with all the same hint.
+	var hint wtdb.BreachHint
+	for i := 0; i < numUpdates; i++ {
+		id := *id(i)
+		session := &wtdb.SessionInfo{
+			ID: id,
+			Policy: wtpolicy.Policy{
+				MaxUpdates: 3,
+			},
+			RewardAddress: []byte{},
+		}
+		h.insertSession(session, nil)
+
+		update := &wtdb.SessionStateUpdate{
+			ID:     id,
+			SeqNum: 1,
+			Hint:   hint, // Use same hint to cause multiple matches
+		}
+		h.insertUpdate(update, nil)
+	}
+
+	// Query the db for matches on the chosen hint.
+	matches := h.queryMatches(hint)
+	if len(matches) != numUpdates {
+		h.t.Fatalf("num updates mismatch, want: %d, got: %d",
+			numUpdates, len(matches))
+	}
+
+	// Assert that the hints are what we asked for, and compute the set of
+	// sessions returned.
+	sessions := make(map[wtdb.SessionID]struct{})
+	for _, match := range matches {
+		if match.Hint != hint {
+			h.t.Fatalf("hint mismatch, want: %v, got: %v",
+				hint, match.Hint)
+		}
+		sessions[match.ID] = struct{}{}
+	}
+
+	// Assert that the sessions returned match the session ids of the
+	// sessions we initially created.
+	for i := 0; i < numUpdates; i++ {
+		if _, ok := sessions[*id(i)]; !ok {
+			h.t.Fatalf("match for session %v not found", *id(i))
+		}
+	}
+}
+
+// testLookoutTip asserts that the database properly stores and returns the
+// lookout tip block epochs. It also asserts that the epoch returned is nil when
+// no tip has ever been set.
+func testLookoutTip(h *towerDBHarness) {
+	// Retrieve lookout tip on fresh db.
+	epoch, err := h.db.GetLookoutTip()
+	if err != nil {
+		h.t.Fatalf("unable to fetch lookout tip: %v", err)
+	}
+
+	// Assert that the epoch is nil.
+	if epoch != nil {
+		h.t.Fatalf("lookout tip should not be set, found: %v", epoch)
+	}
+
+	// Create a closure that inserts an epoch, retrieves it, and asserts
+	// that the returned epoch matches what was inserted.
+	setAndCheck := func(i int) {
+		expEpoch := epochFromInt(1)
+		err = h.db.SetLookoutTip(expEpoch)
+		if err != nil {
+			h.t.Fatalf("unable to set lookout tip: %v", err)
+		}
+
+		epoch, err = h.db.GetLookoutTip()
+		if err != nil {
+			h.t.Fatalf("unable to fetch lookout tip: %v", err)
+		}
+
+		if !reflect.DeepEqual(epoch, expEpoch) {
+			h.t.Fatalf("lookout tip mismatch, want: %v, got: %v",
+				expEpoch, epoch)
+		}
+	}
+
+	// Set and assert the lookout tip.
+	for i := 0; i < 5; i++ {
+		setAndCheck(i)
+	}
+}
+
+// testDeleteSession asserts the behavior of a tower database when deleting
+// session data. The test asserts that the only proper the target session is
+// remmoved, and that only updates for a particular session are pruned.
+func testDeleteSession(h *towerDBHarness) {
+	// First, create a session so that the database is not empty.
+	id0 := id(0)
+	session0 := &wtdb.SessionInfo{
+		ID: *id0,
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	}
+	h.insertSession(session0, nil)
+
+	// Now, attempt to delete a session which does not exist, that is also
+	// different from the first one created.
+	id1 := id(1)
+	h.deleteSession(*id1, wtdb.ErrSessionNotFound)
+
+	// The first session should still be present.
+	h.getSession(id0, nil)
+
+	// Now insert a second session under a different id.
+	session1 := &wtdb.SessionInfo{
+		ID: *id1,
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	}
+	h.insertSession(session1, nil)
+
+	// Create and insert updates for both sessions that have the same hint.
+	var hint wtdb.BreachHint
+	update0 := &wtdb.SessionStateUpdate{
+		ID:            *id0,
+		Hint:          hint,
+		SeqNum:        1,
+		EncryptedBlob: []byte{},
+	}
+	update1 := &wtdb.SessionStateUpdate{
+		ID:            *id1,
+		Hint:          hint,
+		SeqNum:        1,
+		EncryptedBlob: []byte{},
+	}
+
+	// Insert both updates should succeed.
+	h.insertUpdate(update0, nil)
+	h.insertUpdate(update1, nil)
+
+	// Remove the new session, which should succeed.
+	h.deleteSession(*id1, nil)
+
+	// The first session should still be present.
+	h.getSession(id0, nil)
+
+	// The second session should be removed.
+	h.getSession(id1, wtdb.ErrSessionNotFound)
+
+	// Assert that only one update is still present.
+	matches := h.queryMatches(hint)
+	if len(matches) != 1 {
+		h.t.Fatalf("expected one update, found: %d", len(matches))
+	}
+
+	// Assert that the update belongs to the first session.
+	if matches[0].ID != *id0 {
+		h.t.Fatalf("expected match for %v, instead is for: %v",
+			*id0, matches[0].ID)
+	}
+
+	// Finally, remove the first session added.
+	h.deleteSession(*id0, nil)
+
+	// The session should no longer be present.
+	h.getSession(id0, wtdb.ErrSessionNotFound)
+
+	// No matches should exist for this hint.
+	matches = h.queryMatches(hint)
+	if len(matches) != 0 {
+		h.t.Fatalf("expected zero updates, found: %d", len(matches))
+	}
+}
+
+type stateUpdateTest struct {
+	session    *wtdb.SessionInfo
+	sessionErr error
+	updates    []*wtdb.SessionStateUpdate
+	updateErrs []error
+}
+
+func runStateUpdateTest(test stateUpdateTest) func(*towerDBHarness) {
+	return func(h *towerDBHarness) {
+		// We may need to modify the initial session as we process
+		// updates to discern the expected state of the session. We'll
+		// create a copy of the test session if necessary to prevent
+		// mutations from impacting other tests.
+		var expSession *wtdb.SessionInfo
+
+		// Create the session if the tests requests one.
+		if test.session != nil {
+			// Copy the initial session and insert it into the
+			// database.
+			ogSession := *test.session
+			expErr := test.sessionErr
+			h.insertSession(&ogSession, expErr)
+
+			if expErr != nil {
+				return
+			}
+
+			// Copy the initial state of the accepted session.
+			expSession = &wtdb.SessionInfo{}
+			*expSession = *test.session
+		}
+
+		if len(test.updates) != len(test.updateErrs) {
+			h.t.Fatalf("malformed test case, num updates " +
+				"should match num errors")
+		}
+
+		// Send any updates provided in the test.
+		for i, update := range test.updates {
+			expErr := test.updateErrs[i]
+			h.insertUpdate(update, expErr)
+
+			if expErr != nil {
+				continue
+			}
+
+			// Don't perform the following checks and modfications
+			// if we don't have an expected session to compare
+			// against.
+			if expSession == nil {
+				continue
+			}
+
+			// Update the session's last applied and client last
+			// applied.
+			expSession.LastApplied = update.SeqNum
+			expSession.ClientLastApplied = update.LastApplied
+
+			match := h.hasUpdate(update.Hint)
+			if !reflect.DeepEqual(match.SessionInfo, expSession) {
+				h.t.Fatalf("expected session: %v, got: %v",
+					expSession, match.SessionInfo)
+			}
+		}
+	}
+}
+
+var stateUpdateNoSession = stateUpdateTest{
+	session: nil,
+	updates: []*wtdb.SessionStateUpdate{
+		{ID: *id(0), SeqNum: 1, LastApplied: 0},
+	},
+	updateErrs: []error{
+		wtdb.ErrSessionNotFound,
+	},
+}
+
+var stateUpdateExhaustSession = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 1, 0),
+		updateFromInt(id(0), 2, 0),
+		updateFromInt(id(0), 3, 0),
+		updateFromInt(id(0), 4, 0),
+	},
+	updateErrs: []error{
+		nil, nil, nil, wtdb.ErrSessionConsumed,
+	},
+}
+
+var stateUpdateSeqNumEqualLastApplied = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 1, 0),
+		updateFromInt(id(0), 2, 1),
+		updateFromInt(id(0), 3, 2),
+		updateFromInt(id(0), 3, 3),
+	},
+	updateErrs: []error{
+		nil, nil, nil, wtdb.ErrSeqNumAlreadyApplied,
+	},
+}
+
+var stateUpdateSeqNumLTLastApplied = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 1, 0),
+		updateFromInt(id(0), 2, 1),
+		updateFromInt(id(0), 1, 2),
+	},
+	updateErrs: []error{
+		nil, nil, wtdb.ErrSeqNumAlreadyApplied,
+	},
+}
+
+var stateUpdateSeqNumZeroInvalid = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 0, 0),
+	},
+	updateErrs: []error{
+		wtdb.ErrSeqNumAlreadyApplied,
+	},
+}
+
+var stateUpdateSkipSeqNum = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 2, 0),
+	},
+	updateErrs: []error{
+		wtdb.ErrUpdateOutOfOrder,
+	},
+}
+
+var stateUpdateRevertSeqNum = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 1, 0),
+		updateFromInt(id(0), 2, 0),
+		updateFromInt(id(0), 1, 0),
+	},
+	updateErrs: []error{
+		nil, nil, wtdb.ErrUpdateOutOfOrder,
+	},
+}
+
+var stateUpdateRevertLastApplied = stateUpdateTest{
+	session: &wtdb.SessionInfo{
+		ID: *id(0),
+		Policy: wtpolicy.Policy{
+			MaxUpdates: 3,
+		},
+		RewardAddress: []byte{},
+	},
+	updates: []*wtdb.SessionStateUpdate{
+		updateFromInt(id(0), 1, 0),
+		updateFromInt(id(0), 2, 1),
+		updateFromInt(id(0), 3, 2),
+		updateFromInt(id(0), 4, 1),
+	},
+	updateErrs: []error{
+		nil, nil, nil, wtdb.ErrLastAppliedReversion,
+	},
+}
+
+func TestTowerDB(t *testing.T) {
+	dbs := []struct {
+		name string
+		init dbInit
+	}{
+		{
+			name: "fresh boltdb",
+			init: func(t *testing.T) (watchtower.DB, func()) {
+				path, err := ioutil.TempDir("", "towerdb")
+				if err != nil {
+					t.Fatalf("unable to make temp dir: %v",
+						err)
+				}
+
+				db, err := wtdb.OpenTowerDB(path)
+				if err != nil {
+					os.RemoveAll(path)
+					t.Fatalf("unable to open db: %v", err)
+				}
+
+				cleanup := func() {
+					db.Close()
+					os.RemoveAll(path)
+				}
+
+				return db, cleanup
+			},
+		},
+		{
+			name: "reopened boltdb",
+			init: func(t *testing.T) (watchtower.DB, func()) {
+				path, err := ioutil.TempDir("", "towerdb")
+				if err != nil {
+					t.Fatalf("unable to make temp dir: %v",
+						err)
+				}
+
+				db, err := wtdb.OpenTowerDB(path)
+				if err != nil {
+					os.RemoveAll(path)
+					t.Fatalf("unable to open db: %v", err)
+				}
+				db.Close()
+
+				// Open the db again, ensuring we test a
+				// different path during open and that all
+				// buckets remain initialized.
+				db, err = wtdb.OpenTowerDB(path)
+				if err != nil {
+					os.RemoveAll(path)
+					t.Fatalf("unable to open db: %v", err)
+				}
+
+				cleanup := func() {
+					db.Close()
+					os.RemoveAll(path)
+				}
+
+				return db, cleanup
+			},
+		},
+		{
+			name: "mock",
+			init: func(t *testing.T) (watchtower.DB, func()) {
+				return wtmock.NewTowerDB(), func() {}
+			},
+		},
+	}
+
+	tests := []struct {
+		name string
+		run  func(*towerDBHarness)
+	}{
+		{
+			name: "create session",
+			run:  testInsertSession,
+		},
+		{
+			name: "delete session",
+			run:  testDeleteSession,
+		},
+		{
+			name: "state update no session",
+			run:  runStateUpdateTest(stateUpdateNoSession),
+		},
+		{
+			name: "state update exhaust session",
+			run:  runStateUpdateTest(stateUpdateExhaustSession),
+		},
+		{
+			name: "state update seqnum equal last applied",
+			run: runStateUpdateTest(
+				stateUpdateSeqNumEqualLastApplied,
+			),
+		},
+		{
+			name: "state update seqnum less than last applied",
+			run: runStateUpdateTest(
+				stateUpdateSeqNumLTLastApplied,
+			),
+		},
+		{
+			name: "state update seqnum zero invalid",
+			run:  runStateUpdateTest(stateUpdateSeqNumZeroInvalid),
+		},
+		{
+			name: "state update skip seqnum",
+			run:  runStateUpdateTest(stateUpdateSkipSeqNum),
+		},
+		{
+			name: "state update revert seqnum",
+			run:  runStateUpdateTest(stateUpdateRevertSeqNum),
+		},
+		{
+			name: "state update revert last applied",
+			run:  runStateUpdateTest(stateUpdateRevertLastApplied),
+		},
+		{
+			name: "multiple breach matches",
+			run:  testMultipleMatches,
+		},
+		{
+			name: "lookout tip",
+			run:  testLookoutTip,
+		},
+	}
+
+	for _, database := range dbs {
+		db := database
+		t.Run(db.name, func(t *testing.T) {
+			t.Parallel()
+
+			for _, test := range tests {
+				t.Run(test.name, func(t *testing.T) {
+					h, cleanup := newTowerDBHarness(
+						t, db.init,
+					)
+					defer cleanup()
+
+					test.run(h)
+				})
+			}
+		})
+	}
+}
+
+// id creates a session id from an integer.
+func id(i int) *wtdb.SessionID {
+	var id wtdb.SessionID
+	binary.BigEndian.PutUint32(id[:4], uint32(i))
+	return &id
+}
+
+// updateFromInt creates a unique update for a given (session, seqnum) pair. The
+// lastApplied argument can be used to construct updates simulating different
+// levels of synchronicity between client and db.
+func updateFromInt(id *wtdb.SessionID, i int,
+	lastApplied uint16) *wtdb.SessionStateUpdate {
+
+	// Ensure the hint is unique.
+	var hint wtdb.BreachHint
+	copy(hint[:4], id[:4])
+	binary.BigEndian.PutUint16(hint[4:6], uint16(i))
+
+	return &wtdb.SessionStateUpdate{
+		ID:            *id,
+		Hint:          hint,
+		SeqNum:        uint16(i),
+		LastApplied:   lastApplied,
+		EncryptedBlob: []byte{byte(i)},
+	}
+}
+
+// epochFromInt creates a block epoch from an integer.
+func epochFromInt(i int) *chainntnfs.BlockEpoch {
+	var hash chainhash.Hash
+	binary.BigEndian.PutUint32(hash[:4], uint32(i))
+
+	return &chainntnfs.BlockEpoch{
+		Hash:   &hash,
+		Height: int32(i),
+	}
+}