v3_server.go 17 KB

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  1. // Copyright 2015 The etcd Authors
  2. //
  3. // Licensed under the Apache License, Version 2.0 (the "License");
  4. // you may not use this file except in compliance with the License.
  5. // You may obtain a copy of the License at
  6. //
  7. // http://www.apache.org/licenses/LICENSE-2.0
  8. //
  9. // Unless required by applicable law or agreed to in writing, software
  10. // distributed under the License is distributed on an "AS IS" BASIS,
  11. // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12. // See the License for the specific language governing permissions and
  13. // limitations under the License.
  14. package etcdserver
  15. import (
  16. "strconv"
  17. "strings"
  18. "time"
  19. pb "github.com/coreos/etcd/etcdserver/etcdserverpb"
  20. "github.com/coreos/etcd/lease"
  21. "github.com/coreos/etcd/lease/leasehttp"
  22. "github.com/coreos/etcd/mvcc"
  23. "golang.org/x/net/context"
  24. "google.golang.org/grpc/metadata"
  25. )
  26. const (
  27. // the max request size that raft accepts.
  28. // TODO: make this a flag? But we probably do not want to
  29. // accept large request which might block raft stream. User
  30. // specify a large value might end up with shooting in the foot.
  31. maxRequestBytes = 1.5 * 1024 * 1024
  32. // max timeout for waiting a v3 request to go through raft.
  33. maxV3RequestTimeout = 5 * time.Second
  34. // In the health case, there might be a small gap (10s of entries) between
  35. // the applied index and commited index.
  36. // However, if the committed entries are very heavy to apply, the gap might grow.
  37. // We should stop accepting new proposals if the gap growing to a certain point.
  38. maxGapBetweenApplyAndCommitIndex = 1000
  39. )
  40. type RaftKV interface {
  41. Range(ctx context.Context, r *pb.RangeRequest) (*pb.RangeResponse, error)
  42. Put(ctx context.Context, r *pb.PutRequest) (*pb.PutResponse, error)
  43. DeleteRange(ctx context.Context, r *pb.DeleteRangeRequest) (*pb.DeleteRangeResponse, error)
  44. Txn(ctx context.Context, r *pb.TxnRequest) (*pb.TxnResponse, error)
  45. Compact(ctx context.Context, r *pb.CompactionRequest) (*pb.CompactionResponse, error)
  46. }
  47. type Lessor interface {
  48. // LeaseGrant sends LeaseGrant request to raft and apply it after committed.
  49. LeaseGrant(ctx context.Context, r *pb.LeaseGrantRequest) (*pb.LeaseGrantResponse, error)
  50. // LeaseRevoke sends LeaseRevoke request to raft and apply it after committed.
  51. LeaseRevoke(ctx context.Context, r *pb.LeaseRevokeRequest) (*pb.LeaseRevokeResponse, error)
  52. // LeaseRenew renews the lease with given ID. The renewed TTL is returned. Or an error
  53. // is returned.
  54. LeaseRenew(id lease.LeaseID) (int64, error)
  55. }
  56. type Authenticator interface {
  57. AuthEnable(ctx context.Context, r *pb.AuthEnableRequest) (*pb.AuthEnableResponse, error)
  58. AuthDisable(ctx context.Context, r *pb.AuthDisableRequest) (*pb.AuthDisableResponse, error)
  59. Authenticate(ctx context.Context, r *pb.AuthenticateRequest) (*pb.AuthenticateResponse, error)
  60. UserAdd(ctx context.Context, r *pb.AuthUserAddRequest) (*pb.AuthUserAddResponse, error)
  61. UserDelete(ctx context.Context, r *pb.AuthUserDeleteRequest) (*pb.AuthUserDeleteResponse, error)
  62. UserChangePassword(ctx context.Context, r *pb.AuthUserChangePasswordRequest) (*pb.AuthUserChangePasswordResponse, error)
  63. UserGrantRole(ctx context.Context, r *pb.AuthUserGrantRoleRequest) (*pb.AuthUserGrantRoleResponse, error)
  64. UserGet(ctx context.Context, r *pb.AuthUserGetRequest) (*pb.AuthUserGetResponse, error)
  65. UserRevokeRole(ctx context.Context, r *pb.AuthUserRevokeRoleRequest) (*pb.AuthUserRevokeRoleResponse, error)
  66. RoleAdd(ctx context.Context, r *pb.AuthRoleAddRequest) (*pb.AuthRoleAddResponse, error)
  67. RoleGrantPermission(ctx context.Context, r *pb.AuthRoleGrantPermissionRequest) (*pb.AuthRoleGrantPermissionResponse, error)
  68. RoleGet(ctx context.Context, r *pb.AuthRoleGetRequest) (*pb.AuthRoleGetResponse, error)
  69. RoleRevokePermission(ctx context.Context, r *pb.AuthRoleRevokePermissionRequest) (*pb.AuthRoleRevokePermissionResponse, error)
  70. RoleDelete(ctx context.Context, r *pb.AuthRoleDeleteRequest) (*pb.AuthRoleDeleteResponse, error)
  71. UserList(ctx context.Context, r *pb.AuthUserListRequest) (*pb.AuthUserListResponse, error)
  72. RoleList(ctx context.Context, r *pb.AuthRoleListRequest) (*pb.AuthRoleListResponse, error)
  73. }
  74. func (s *EtcdServer) Range(ctx context.Context, r *pb.RangeRequest) (*pb.RangeResponse, error) {
  75. var result *applyResult
  76. var err error
  77. if r.Serializable {
  78. var user string
  79. user, err = s.usernameFromCtx(ctx)
  80. if err != nil {
  81. return nil, err
  82. }
  83. result = s.applyV3.Apply(
  84. &pb.InternalRaftRequest{
  85. Header: &pb.RequestHeader{Username: user},
  86. Range: r})
  87. } else {
  88. result, err = s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{Range: r})
  89. }
  90. if err != nil {
  91. return nil, err
  92. }
  93. if result.err != nil {
  94. return nil, result.err
  95. }
  96. return result.resp.(*pb.RangeResponse), nil
  97. }
  98. func (s *EtcdServer) Put(ctx context.Context, r *pb.PutRequest) (*pb.PutResponse, error) {
  99. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{Put: r})
  100. if err != nil {
  101. return nil, err
  102. }
  103. if result.err != nil {
  104. return nil, result.err
  105. }
  106. return result.resp.(*pb.PutResponse), nil
  107. }
  108. func (s *EtcdServer) DeleteRange(ctx context.Context, r *pb.DeleteRangeRequest) (*pb.DeleteRangeResponse, error) {
  109. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{DeleteRange: r})
  110. if err != nil {
  111. return nil, err
  112. }
  113. if result.err != nil {
  114. return nil, result.err
  115. }
  116. return result.resp.(*pb.DeleteRangeResponse), nil
  117. }
  118. func (s *EtcdServer) Txn(ctx context.Context, r *pb.TxnRequest) (*pb.TxnResponse, error) {
  119. var result *applyResult
  120. var err error
  121. if isTxnSerializable(r) {
  122. user, err := s.usernameFromCtx(ctx)
  123. if err != nil {
  124. return nil, err
  125. }
  126. result = s.applyV3.Apply(
  127. &pb.InternalRaftRequest{
  128. Header: &pb.RequestHeader{Username: user},
  129. Txn: r})
  130. } else {
  131. result, err = s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{Txn: r})
  132. }
  133. if err != nil {
  134. return nil, err
  135. }
  136. if result.err != nil {
  137. return nil, result.err
  138. }
  139. return result.resp.(*pb.TxnResponse), nil
  140. }
  141. func isTxnSerializable(r *pb.TxnRequest) bool {
  142. for _, u := range r.Success {
  143. if r := u.GetRequestRange(); r == nil || !r.Serializable {
  144. return false
  145. }
  146. }
  147. for _, u := range r.Failure {
  148. if r := u.GetRequestRange(); r == nil || !r.Serializable {
  149. return false
  150. }
  151. }
  152. return true
  153. }
  154. func (s *EtcdServer) Compact(ctx context.Context, r *pb.CompactionRequest) (*pb.CompactionResponse, error) {
  155. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{Compaction: r})
  156. if r.Physical && result != nil && result.physc != nil {
  157. <-result.physc
  158. // The compaction is done deleting keys; the hash is now settled
  159. // but the data is not necessarily committed. If there's a crash,
  160. // the hash may revert to a hash prior to compaction completing
  161. // if the compaction resumes. Force the finished compaction to
  162. // commit so it won't resume following a crash.
  163. s.be.ForceCommit()
  164. }
  165. if err != nil {
  166. return nil, err
  167. }
  168. if result.err != nil {
  169. return nil, result.err
  170. }
  171. resp := result.resp.(*pb.CompactionResponse)
  172. if resp == nil {
  173. resp = &pb.CompactionResponse{}
  174. }
  175. if resp.Header == nil {
  176. resp.Header = &pb.ResponseHeader{}
  177. }
  178. resp.Header.Revision = s.kv.Rev()
  179. return resp, nil
  180. }
  181. func (s *EtcdServer) LeaseGrant(ctx context.Context, r *pb.LeaseGrantRequest) (*pb.LeaseGrantResponse, error) {
  182. // no id given? choose one
  183. for r.ID == int64(lease.NoLease) {
  184. // only use positive int64 id's
  185. r.ID = int64(s.reqIDGen.Next() & ((1 << 63) - 1))
  186. }
  187. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{LeaseGrant: r})
  188. if err != nil {
  189. return nil, err
  190. }
  191. if result.err != nil {
  192. return nil, result.err
  193. }
  194. return result.resp.(*pb.LeaseGrantResponse), nil
  195. }
  196. func (s *EtcdServer) LeaseRevoke(ctx context.Context, r *pb.LeaseRevokeRequest) (*pb.LeaseRevokeResponse, error) {
  197. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{LeaseRevoke: r})
  198. if err != nil {
  199. return nil, err
  200. }
  201. if result.err != nil {
  202. return nil, result.err
  203. }
  204. return result.resp.(*pb.LeaseRevokeResponse), nil
  205. }
  206. func (s *EtcdServer) LeaseRenew(id lease.LeaseID) (int64, error) {
  207. ttl, err := s.lessor.Renew(id)
  208. if err == nil {
  209. return ttl, nil
  210. }
  211. if err != lease.ErrNotPrimary {
  212. return -1, err
  213. }
  214. // renewals don't go through raft; forward to leader manually
  215. leader := s.cluster.Member(s.Leader())
  216. for i := 0; i < 5 && leader == nil; i++ {
  217. // wait an election
  218. dur := time.Duration(s.Cfg.ElectionTicks) * time.Duration(s.Cfg.TickMs) * time.Millisecond
  219. select {
  220. case <-time.After(dur):
  221. leader = s.cluster.Member(s.Leader())
  222. case <-s.done:
  223. return -1, ErrStopped
  224. }
  225. }
  226. if leader == nil || len(leader.PeerURLs) == 0 {
  227. return -1, ErrNoLeader
  228. }
  229. for _, url := range leader.PeerURLs {
  230. lurl := url + "/leases"
  231. ttl, err = leasehttp.RenewHTTP(id, lurl, s.peerRt, s.Cfg.peerDialTimeout())
  232. if err == nil {
  233. break
  234. }
  235. }
  236. return ttl, err
  237. }
  238. func (s *EtcdServer) Alarm(ctx context.Context, r *pb.AlarmRequest) (*pb.AlarmResponse, error) {
  239. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{Alarm: r})
  240. if err != nil {
  241. return nil, err
  242. }
  243. if result.err != nil {
  244. return nil, result.err
  245. }
  246. return result.resp.(*pb.AlarmResponse), nil
  247. }
  248. func (s *EtcdServer) AuthEnable(ctx context.Context, r *pb.AuthEnableRequest) (*pb.AuthEnableResponse, error) {
  249. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthEnable: r})
  250. if err != nil {
  251. return nil, err
  252. }
  253. if result.err != nil {
  254. return nil, result.err
  255. }
  256. return result.resp.(*pb.AuthEnableResponse), nil
  257. }
  258. func (s *EtcdServer) AuthDisable(ctx context.Context, r *pb.AuthDisableRequest) (*pb.AuthDisableResponse, error) {
  259. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthDisable: r})
  260. if err != nil {
  261. return nil, err
  262. }
  263. if result.err != nil {
  264. return nil, result.err
  265. }
  266. return result.resp.(*pb.AuthDisableResponse), nil
  267. }
  268. func (s *EtcdServer) Authenticate(ctx context.Context, r *pb.AuthenticateRequest) (*pb.AuthenticateResponse, error) {
  269. st, err := s.AuthStore().GenSimpleToken()
  270. if err != nil {
  271. return nil, err
  272. }
  273. internalReq := &pb.InternalAuthenticateRequest{
  274. Name: r.Name,
  275. Password: r.Password,
  276. SimpleToken: st,
  277. }
  278. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{Authenticate: internalReq})
  279. if err != nil {
  280. return nil, err
  281. }
  282. if result.err != nil {
  283. return nil, result.err
  284. }
  285. return result.resp.(*pb.AuthenticateResponse), nil
  286. }
  287. func (s *EtcdServer) UserAdd(ctx context.Context, r *pb.AuthUserAddRequest) (*pb.AuthUserAddResponse, error) {
  288. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserAdd: r})
  289. if err != nil {
  290. return nil, err
  291. }
  292. if result.err != nil {
  293. return nil, result.err
  294. }
  295. return result.resp.(*pb.AuthUserAddResponse), nil
  296. }
  297. func (s *EtcdServer) UserDelete(ctx context.Context, r *pb.AuthUserDeleteRequest) (*pb.AuthUserDeleteResponse, error) {
  298. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserDelete: r})
  299. if err != nil {
  300. return nil, err
  301. }
  302. if result.err != nil {
  303. return nil, result.err
  304. }
  305. return result.resp.(*pb.AuthUserDeleteResponse), nil
  306. }
  307. func (s *EtcdServer) UserChangePassword(ctx context.Context, r *pb.AuthUserChangePasswordRequest) (*pb.AuthUserChangePasswordResponse, error) {
  308. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserChangePassword: r})
  309. if err != nil {
  310. return nil, err
  311. }
  312. if result.err != nil {
  313. return nil, result.err
  314. }
  315. return result.resp.(*pb.AuthUserChangePasswordResponse), nil
  316. }
  317. func (s *EtcdServer) UserGrantRole(ctx context.Context, r *pb.AuthUserGrantRoleRequest) (*pb.AuthUserGrantRoleResponse, error) {
  318. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserGrantRole: r})
  319. if err != nil {
  320. return nil, err
  321. }
  322. if result.err != nil {
  323. return nil, result.err
  324. }
  325. return result.resp.(*pb.AuthUserGrantRoleResponse), nil
  326. }
  327. func (s *EtcdServer) UserGet(ctx context.Context, r *pb.AuthUserGetRequest) (*pb.AuthUserGetResponse, error) {
  328. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserGet: r})
  329. if err != nil {
  330. return nil, err
  331. }
  332. if result.err != nil {
  333. return nil, result.err
  334. }
  335. return result.resp.(*pb.AuthUserGetResponse), nil
  336. }
  337. func (s *EtcdServer) UserList(ctx context.Context, r *pb.AuthUserListRequest) (*pb.AuthUserListResponse, error) {
  338. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserList: r})
  339. if err != nil {
  340. return nil, err
  341. }
  342. if result.err != nil {
  343. return nil, result.err
  344. }
  345. return result.resp.(*pb.AuthUserListResponse), nil
  346. }
  347. func (s *EtcdServer) UserRevokeRole(ctx context.Context, r *pb.AuthUserRevokeRoleRequest) (*pb.AuthUserRevokeRoleResponse, error) {
  348. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthUserRevokeRole: r})
  349. if err != nil {
  350. return nil, err
  351. }
  352. if result.err != nil {
  353. return nil, result.err
  354. }
  355. return result.resp.(*pb.AuthUserRevokeRoleResponse), nil
  356. }
  357. func (s *EtcdServer) RoleAdd(ctx context.Context, r *pb.AuthRoleAddRequest) (*pb.AuthRoleAddResponse, error) {
  358. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthRoleAdd: r})
  359. if err != nil {
  360. return nil, err
  361. }
  362. if result.err != nil {
  363. return nil, result.err
  364. }
  365. return result.resp.(*pb.AuthRoleAddResponse), nil
  366. }
  367. func (s *EtcdServer) RoleGrantPermission(ctx context.Context, r *pb.AuthRoleGrantPermissionRequest) (*pb.AuthRoleGrantPermissionResponse, error) {
  368. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthRoleGrantPermission: r})
  369. if err != nil {
  370. return nil, err
  371. }
  372. if result.err != nil {
  373. return nil, result.err
  374. }
  375. return result.resp.(*pb.AuthRoleGrantPermissionResponse), nil
  376. }
  377. func (s *EtcdServer) RoleGet(ctx context.Context, r *pb.AuthRoleGetRequest) (*pb.AuthRoleGetResponse, error) {
  378. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthRoleGet: r})
  379. if err != nil {
  380. return nil, err
  381. }
  382. if result.err != nil {
  383. return nil, result.err
  384. }
  385. return result.resp.(*pb.AuthRoleGetResponse), nil
  386. }
  387. func (s *EtcdServer) RoleList(ctx context.Context, r *pb.AuthRoleListRequest) (*pb.AuthRoleListResponse, error) {
  388. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthRoleList: r})
  389. if err != nil {
  390. return nil, err
  391. }
  392. if result.err != nil {
  393. return nil, result.err
  394. }
  395. return result.resp.(*pb.AuthRoleListResponse), nil
  396. }
  397. func (s *EtcdServer) RoleRevokePermission(ctx context.Context, r *pb.AuthRoleRevokePermissionRequest) (*pb.AuthRoleRevokePermissionResponse, error) {
  398. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthRoleRevokePermission: r})
  399. if err != nil {
  400. return nil, err
  401. }
  402. if result.err != nil {
  403. return nil, result.err
  404. }
  405. return result.resp.(*pb.AuthRoleRevokePermissionResponse), nil
  406. }
  407. func (s *EtcdServer) RoleDelete(ctx context.Context, r *pb.AuthRoleDeleteRequest) (*pb.AuthRoleDeleteResponse, error) {
  408. result, err := s.processInternalRaftRequest(ctx, pb.InternalRaftRequest{AuthRoleDelete: r})
  409. if err != nil {
  410. return nil, err
  411. }
  412. if result.err != nil {
  413. return nil, result.err
  414. }
  415. return result.resp.(*pb.AuthRoleDeleteResponse), nil
  416. }
  417. func (s *EtcdServer) isValidSimpleToken(token string) bool {
  418. splitted := strings.Split(token, ".")
  419. if len(splitted) != 2 {
  420. return false
  421. }
  422. index, err := strconv.Atoi(splitted[1])
  423. if err != nil {
  424. return false
  425. }
  426. // CAUTION: below index synchronization is required because this node
  427. // might not receive and apply the log entry of Authenticate() RPC.
  428. authApplied := false
  429. for i := 0; i < 10; i++ {
  430. if uint64(index) <= s.getAppliedIndex() {
  431. authApplied = true
  432. break
  433. }
  434. time.Sleep(100 * time.Millisecond)
  435. }
  436. if !authApplied {
  437. plog.Errorf("timeout of waiting Authenticate() RPC")
  438. return false
  439. }
  440. return true
  441. }
  442. func (s *EtcdServer) usernameFromCtx(ctx context.Context) (string, error) {
  443. md, ok := metadata.FromContext(ctx)
  444. if !ok {
  445. return "", nil
  446. }
  447. ts, tok := md["token"]
  448. if !tok {
  449. return "", nil
  450. }
  451. token := ts[0]
  452. if !s.isValidSimpleToken(token) {
  453. return "", ErrInvalidAuthToken
  454. }
  455. username, uok := s.AuthStore().UsernameFromToken(token)
  456. if !uok {
  457. plog.Warningf("invalid auth token: %s", token)
  458. return "", ErrInvalidAuthToken
  459. }
  460. return username, nil
  461. }
  462. func (s *EtcdServer) processInternalRaftRequest(ctx context.Context, r pb.InternalRaftRequest) (*applyResult, error) {
  463. ai := s.getAppliedIndex()
  464. ci := s.getCommittedIndex()
  465. if ci > ai+maxGapBetweenApplyAndCommitIndex {
  466. return nil, ErrTooManyRequests
  467. }
  468. r.Header = &pb.RequestHeader{
  469. ID: s.reqIDGen.Next(),
  470. }
  471. username, err := s.usernameFromCtx(ctx)
  472. if err != nil {
  473. return nil, err
  474. }
  475. r.Header.Username = username
  476. data, err := r.Marshal()
  477. if err != nil {
  478. return nil, err
  479. }
  480. if len(data) > maxRequestBytes {
  481. return nil, ErrRequestTooLarge
  482. }
  483. id := r.ID
  484. if id == 0 {
  485. id = r.Header.ID
  486. }
  487. ch := s.w.Register(id)
  488. cctx, cancel := context.WithTimeout(ctx, maxV3RequestTimeout)
  489. defer cancel()
  490. start := time.Now()
  491. s.r.Propose(cctx, data)
  492. proposalsPending.Inc()
  493. defer proposalsPending.Dec()
  494. select {
  495. case x := <-ch:
  496. return x.(*applyResult), nil
  497. case <-cctx.Done():
  498. proposalsFailed.Inc()
  499. s.w.Trigger(id, nil) // GC wait
  500. return nil, s.parseProposeCtxErr(cctx.Err(), start)
  501. case <-s.done:
  502. return nil, ErrStopped
  503. }
  504. }
  505. // Watchable returns a watchable interface attached to the etcdserver.
  506. func (s *EtcdServer) Watchable() mvcc.WatchableKV { return s.KV() }