[release-3.5] etcdserver: add cluster id check for hashKVHandler

api/v3rpc/rpctypes/error.go

@@ -45,6 +45,7 @@ var (
 	ErrGRPCMemberNotLearner       = status.New(codes.FailedPrecondition, "etcdserver: can only promote a learner member").Err()
 	ErrGRPCLearnerNotReady        = status.New(codes.FailedPrecondition, "etcdserver: can only promote a learner member which is in sync with leader").Err()
 	ErrGRPCTooManyLearners        = status.New(codes.FailedPrecondition, "etcdserver: too many learner members in cluster").Err()
+	ErrGRPCClusterIdMismatch      = status.New(codes.FailedPrecondition, "etcdserver: cluster ID mismatch").Err()
 
 	ErrGRPCRequestTooLarge        = status.New(codes.InvalidArgument, "etcdserver: request is too large").Err()
 	ErrGRPCRequestTooManyRequests = status.New(codes.ResourceExhausted, "etcdserver: too many requests").Err()
@@ -114,6 +115,7 @@ var (
 		ErrorDesc(ErrGRPCMemberNotLearner):       ErrGRPCMemberNotLearner,
 		ErrorDesc(ErrGRPCLearnerNotReady):        ErrGRPCLearnerNotReady,
 		ErrorDesc(ErrGRPCTooManyLearners):        ErrGRPCTooManyLearners,
+		ErrorDesc(ErrGRPCClusterIdMismatch):      ErrGRPCClusterIdMismatch,
 
 		ErrorDesc(ErrGRPCRequestTooLarge):        ErrGRPCRequestTooLarge,
 		ErrorDesc(ErrGRPCRequestTooManyRequests): ErrGRPCRequestTooManyRequests,
@@ -200,6 +202,7 @@ var (
 	ErrInvalidAuthToken     = Error(ErrGRPCInvalidAuthToken)
 	ErrAuthOldRevision      = Error(ErrGRPCAuthOldRevision)
 	ErrInvalidAuthMgmt      = Error(ErrGRPCInvalidAuthMgmt)
+	ErrClusterIdMismatch    = Error(ErrGRPCClusterIdMismatch)
 
 	ErrNoLeader                   = Error(ErrGRPCNoLeader)
 	ErrNotLeader                  = Error(ErrGRPCNotLeader)

server/etcdserver/api/rafthttp/http.go

@@ -54,7 +54,7 @@ var (
 	RaftSnapshotPrefix = path.Join(RaftPrefix, "snapshot")
 
 	errIncompatibleVersion = errors.New("incompatible version")
-	errClusterIDMismatch   = errors.New("cluster ID mismatch")
+	ErrClusterIDMismatch   = errors.New("cluster ID mismatch")
 )
 
 type peerGetter interface {
@@ -508,7 +508,7 @@ func checkClusterCompatibilityFromHeader(lg *zap.Logger, localID types.ID, heade
 			zap.String("remote-peer-server-minimum-cluster-version", remoteMinClusterVs),
 			zap.String("remote-peer-cluster-id", gcid),
 		)
-		return errClusterIDMismatch
+		return ErrClusterIDMismatch
 	}
 	return nil
 }

server/etcdserver/api/rafthttp/stream.go

@@ -648,18 +648,18 @@ func (cr *streamReader) dial(t streamType) (io.ReadCloser, error) {
 			}
 			return nil, errIncompatibleVersion
 
-		case errClusterIDMismatch.Error():
+		case ErrClusterIDMismatch.Error():
 			if cr.lg != nil {
 				cr.lg.Warn(
 					"request sent was ignored by remote peer due to cluster ID mismatch",
 					zap.String("remote-peer-id", cr.peerID.String()),
 					zap.String("remote-peer-cluster-id", resp.Header.Get("X-Etcd-Cluster-ID")),
 					zap.String("local-member-id", cr.tr.ID.String()),
 					zap.String("local-member-cluster-id", cr.tr.ClusterID.String()),
-					zap.Error(errClusterIDMismatch),
+					zap.Error(ErrClusterIDMismatch),
 				)
 			}
-			return nil, errClusterIDMismatch
+			return nil, ErrClusterIDMismatch
 
 		default:
 			return nil, fmt.Errorf("unhandled error %q when precondition failed", string(b))

server/etcdserver/api/rafthttp/util.go

@@ -94,7 +94,7 @@ func checkPostResponse(lg *zap.Logger, resp *http.Response, body []byte, req *ht
 				)
 			}
 			return errIncompatibleVersion
-		case errClusterIDMismatch.Error():
+		case ErrClusterIDMismatch.Error():
 			if lg != nil {
 				lg.Error(
 					"request sent was ignored due to cluster ID mismatch",
@@ -103,7 +103,7 @@ func checkPostResponse(lg *zap.Logger, resp *http.Response, body []byte, req *ht
 					zap.String("local-member-cluster-id", req.Header.Get("X-Etcd-Cluster-ID")),
 				)
 			}
-			return errClusterIDMismatch
+			return ErrClusterIDMismatch
 		default:
 			return fmt.Errorf("unhandled error %q when precondition failed", string(body))
 		}

server/etcdserver/corrupt.go

@@ -30,6 +30,7 @@ import (
 	"go.etcd.io/etcd/api/v3/v3rpc/rpctypes"
 	"go.etcd.io/etcd/client/pkg/v3/types"
 	"go.etcd.io/etcd/pkg/v3/traceutil"
+	"go.etcd.io/etcd/server/v3/etcdserver/api/rafthttp"
 	"go.etcd.io/etcd/server/v3/mvcc"
 
 	"go.uber.org/zap"
@@ -155,6 +156,17 @@ func (cm *corruptionChecker) InitialCheck() error {
 					zap.Strings("remote-peer-endpoints", p.eps),
 					zap.Error(err),
 				)
+			case rpctypes.ErrClusterIdMismatch:
+				cm.lg.Warn(
+					"cluster ID mismatch",
+					zap.String("local-member-id", cm.hasher.MemberId().String()),
+					zap.Int64("local-member-revision", h.Revision),
+					zap.Int64("local-member-compact-revision", h.CompactRevision),
+					zap.Uint32("local-member-hash", h.Hash),
+					zap.String("remote-peer-id", p.id.String()),
+					zap.Strings("remote-peer-endpoints", p.eps),
+					zap.Error(err),
+				)
 			}
 		}
 	}
@@ -389,7 +401,7 @@ func (s *EtcdServer) getPeerHashKVs(rev int64) []*peerHashKVResp {
 		var lastErr error
 		for _, ep := range p.eps {
 			ctx, cancel := context.WithTimeout(context.Background(), s.Cfg.ReqTimeout())
-			resp, lastErr := HashByRev(ctx, cc, ep, rev)
+			resp, lastErr := HashByRev(ctx, s.cluster.ID(), cc, ep, rev)
 			cancel()
 			if lastErr == nil {
 				resps = append(resps, &peerHashKVResp{peerInfo: p, resp: resp, err: nil})
@@ -467,6 +479,10 @@ func (h *hashKVHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 		http.Error(w, "bad path", http.StatusBadRequest)
 		return
 	}
+	if gcid := r.Header.Get("X-Etcd-Cluster-ID"); gcid != "" && gcid != h.server.cluster.ID().String() {
+		http.Error(w, rafthttp.ErrClusterIDMismatch.Error(), http.StatusPreconditionFailed)
+		return
+	}
 
 	defer r.Body.Close()
 	b, err := ioutil.ReadAll(r.Body)
@@ -505,7 +521,7 @@ func (h *hashKVHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
 }
 
 // HashByRev fetch hash of kv store at the given rev via http call to the given url
-func HashByRev(ctx context.Context, cc *http.Client, url string, rev int64) (*pb.HashKVResponse, error) {
+func HashByRev(ctx context.Context, cid types.ID, cc *http.Client, url string, rev int64) (*pb.HashKVResponse, error) {
 	hashReq := &pb.HashKVRequest{Revision: rev}
 	hashReqBytes, err := json.Marshal(hashReq)
 	if err != nil {
@@ -518,6 +534,7 @@ func HashByRev(ctx context.Context, cc *http.Client, url string, rev int64) (*pb
 	}
 	req = req.WithContext(ctx)
 	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("X-Etcd-Cluster-ID", cid.String())
 	req.Cancel = ctx.Done()
 
 	resp, err := cc.Do(req)
@@ -537,6 +554,10 @@ func HashByRev(ctx context.Context, cc *http.Client, url string, rev int64) (*pb
 		if strings.Contains(string(b), mvcc.ErrFutureRev.Error()) {
 			return nil, rpctypes.ErrFutureRev
 		}
+	} else if resp.StatusCode == http.StatusPreconditionFailed {
+		if strings.Contains(string(b), rafthttp.ErrClusterIDMismatch.Error()) {
+			return nil, rpctypes.ErrClusterIdMismatch
+		}
 	}
 	if resp.StatusCode != http.StatusOK {
 		return nil, fmt.Errorf("unknown error: %s", string(b))

server/etcdserver/corrupt_test.go

@@ -15,16 +15,28 @@
 package etcdserver
 
 import (
+	"bytes"
 	"context"
+	"encoding/json"
 	"fmt"
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"strconv"
+	"strings"
 	"testing"
 	"time"
 
+	"go.uber.org/zap"
+
+	"go.etcd.io/etcd/server/v3/lease"
+
 	"github.com/stretchr/testify/assert"
 	pb "go.etcd.io/etcd/api/v3/etcdserverpb"
 	"go.etcd.io/etcd/api/v3/v3rpc/rpctypes"
 	"go.etcd.io/etcd/client/pkg/v3/types"
 	"go.etcd.io/etcd/server/v3/mvcc"
+	betesting "go.etcd.io/etcd/server/v3/mvcc/backend/testing"
 	"go.uber.org/zap/zaptest"
 )
 
@@ -85,6 +97,13 @@ func TestInitialCheck(t *testing.T) {
 			hasher:        fakeHasher{hashByRevResponses: []hashByRev{{hash: mvcc.KeyValueHash{Hash: 1, CompactRevision: 1}}}, peerHashes: []*peerHashKVResp{{resp: &pb.HashKVResponse{Header: &pb.ResponseHeader{}, Hash: 2, CompactRevision: 2}}}},
 			expectActions: []string{"MemberId()", "ReqTimeout()", "HashByRev(0)", "PeerHashByRev(0)", "MemberId()", "MemberId()"},
 		},
+		{
+			name: "Cluster ID Mismatch does not fail CorruptionChecker.InitialCheck()",
+			hasher: fakeHasher{
+				peerHashes: []*peerHashKVResp{{err: rpctypes.ErrClusterIdMismatch}},
+			},
+			expectActions: []string{"MemberId()", "ReqTimeout()", "HashByRev(0)", "PeerHashByRev(0)", "MemberId()", "MemberId()"},
+		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.name, func(t *testing.T) {
@@ -202,6 +221,13 @@ func TestPeriodicCheck(t *testing.T) {
 			expectActions: []string{"HashByRev(0)", "PeerHashByRev(0)", "ReqTimeout()", "LinearizableReadNotify()", "HashByRev(0)", "TriggerCorruptAlarm(0)"},
 			expectCorrupt: true,
 		},
+		{
+			name: "Cluster ID Mismatch does not fail CorruptionChecker.PeriodicCheck()",
+			hasher: fakeHasher{
+				peerHashes: []*peerHashKVResp{{err: rpctypes.ErrClusterIdMismatch}},
+			},
+			expectActions: []string{"HashByRev(0)", "PeerHashByRev(0)", "ReqTimeout()", "LinearizableReadNotify()", "HashByRev(0)"},
+		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.name, func(t *testing.T) {
@@ -290,6 +316,14 @@ func TestCompactHashCheck(t *testing.T) {
 			},
 			expectActions: []string{"MemberId()", "ReqTimeout()", "Hashes()", "PeerHashByRev(1)"},
 		},
+		{
+			name: "Cluster ID Mismatch does not fail CorruptionChecker.CompactHashCheck()",
+			hasher: fakeHasher{
+				hashes:     []mvcc.KeyValueHash{{Revision: 1, CompactRevision: 1, Hash: 1}},
+				peerHashes: []*peerHashKVResp{{err: rpctypes.ErrClusterIdMismatch}},
+			},
+			expectActions: []string{"MemberId()", "ReqTimeout()", "Hashes()", "PeerHashByRev(1)"},
+		},
 	}
 	for _, tc := range tcs {
 		t.Run(tc.name, func(t *testing.T) {
@@ -375,3 +409,88 @@ func (f *fakeHasher) TriggerCorruptAlarm(memberId types.ID) {
 	f.actions = append(f.actions, fmt.Sprintf("TriggerCorruptAlarm(%d)", memberId))
 	f.alarmTriggered = true
 }
+
+func TestHashKVHandler(t *testing.T) {
+	var remoteClusterID = 111195
+	var localClusterID = 111196
+	var revision = 1
+
+	etcdSrv := &EtcdServer{}
+	etcdSrv.cluster = newTestCluster(t, nil)
+	etcdSrv.cluster.SetID(types.ID(localClusterID), types.ID(localClusterID))
+	be, _ := betesting.NewDefaultTmpBackend(t)
+	defer betesting.Close(t, be)
+	etcdSrv.kv = mvcc.New(zap.NewNop(), be, &lease.FakeLessor{}, mvcc.StoreConfig{})
+	ph := &hashKVHandler{
+		lg:     zap.NewNop(),
+		server: etcdSrv,
+	}
+	srv := httptest.NewServer(ph)
+	defer srv.Close()
+
+	tests := []struct {
+		name            string
+		remoteClusterID int
+		wcode           int
+		wKeyWords       string
+	}{
+		{
+			name:            "HashKV returns 200 if cluster hash matches",
+			remoteClusterID: localClusterID,
+			wcode:           http.StatusOK,
+			wKeyWords:       "",
+		},
+		{
+			name:            "HashKV returns 400 if cluster hash doesn't matche",
+			remoteClusterID: remoteClusterID,
+			wcode:           http.StatusPreconditionFailed,
+			wKeyWords:       "cluster ID mismatch",
+		},
+	}
+	for i, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			hashReq := &pb.HashKVRequest{Revision: int64(revision)}
+			hashReqBytes, err := json.Marshal(hashReq)
+			if err != nil {
+				t.Fatalf("failed to marshal request: %v", err)
+			}
+			req, err := http.NewRequest(http.MethodGet, srv.URL+PeerHashKVPath, bytes.NewReader(hashReqBytes))
+			if err != nil {
+				t.Fatalf("failed to create request: %v", err)
+			}
+			req.Header.Set("X-Etcd-Cluster-ID", strconv.FormatUint(uint64(tt.remoteClusterID), 16))
+
+			resp, err := http.DefaultClient.Do(req)
+			if err != nil {
+				t.Fatalf("failed to get http response: %v", err)
+			}
+			body, err := io.ReadAll(resp.Body)
+			resp.Body.Close()
+			if err != nil {
+				t.Fatalf("unexpected io.ReadAll error: %v", err)
+			}
+			if resp.StatusCode != tt.wcode {
+				t.Fatalf("#%d: code = %d, want %d", i, resp.StatusCode, tt.wcode)
+			}
+			if resp.StatusCode != http.StatusOK {
+				if !strings.Contains(string(body), tt.wKeyWords) {
+					t.Errorf("#%d: body: %s, want body to contain keywords: %s", i, string(body), tt.wKeyWords)
+				}
+				return
+			}
+
+			hashKVResponse := pb.HashKVResponse{}
+			err = json.Unmarshal(body, &hashKVResponse)
+			if err != nil {
+				t.Fatalf("unmarshal response error: %v", err)
+			}
+			hashValue, _, err := etcdSrv.KV().HashStorage().HashByRev(int64(revision))
+			if err != nil {
+				t.Fatalf("etcd server hash failed: %v", err)
+			}
+			if hashKVResponse.Hash != hashValue.Hash {
+				t.Fatalf("hash value inconsistent: %d != %d", hashKVResponse.Hash, hashValue)
+			}
+		})
+	}
+}

tests/e2e/cluster_test.go

@@ -181,6 +181,17 @@ type etcdProcessClusterConfig struct {
 // newEtcdProcessCluster launches a new cluster from etcd processes, returning
 // a new etcdProcessCluster once all nodes are ready to accept client requests.
 func newEtcdProcessCluster(t testing.TB, cfg *etcdProcessClusterConfig) (*etcdProcessCluster, error) {
+	epc, err := initEtcdProcessCluster(t, cfg)
+	if err != nil {
+		return nil, err
+	}
+
+	return startEtcdProcessCluster(epc, cfg)
+}
+
+// initEtcdProcessCluster initializes a new cluster based on the given config.
+// It doesn't start the cluster.
+func initEtcdProcessCluster(t testing.TB, cfg *etcdProcessClusterConfig) (*etcdProcessCluster, error) {
 	skipInShortMode(t)
 
 	etcdCfgs := cfg.etcdServerProcessConfigs(t)
@@ -199,7 +210,11 @@ func newEtcdProcessCluster(t testing.TB, cfg *etcdProcessClusterConfig) (*etcdPr
 		}
 		epc.procs[i] = proc
 	}
+	return epc, nil
+}
 
+// startEtcdProcessCluster launches a new cluster from etcd processes.
+func startEtcdProcessCluster(epc *etcdProcessCluster, cfg *etcdProcessClusterConfig) (*etcdProcessCluster, error) {
 	if cfg.rollingStart {
 		if err := epc.RollingStart(); err != nil {
 			return nil, fmt.Errorf("Cannot rolling-start: %v", err)