github.com/needkane/go-ethereum@v1.7.4-0.20180131070256-c212876ea2b7/whisper/whisperv6/api.go (about) 1 // Copyright 2016 The go-ethereum Authors 2 // This file is part of the go-ethereum library. 3 // 4 // The go-ethereum library is free software: you can redistribute it and/or modify 5 // it under the terms of the GNU Lesser General Public License as published by 6 // the Free Software Foundation, either version 3 of the License, or 7 // (at your option) any later version. 8 // 9 // The go-ethereum library is distributed in the hope that it will be useful, 10 // but WITHOUT ANY WARRANTY; without even the implied warranty of 11 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 // GNU Lesser General Public License for more details. 13 // 14 // You should have received a copy of the GNU Lesser General Public License 15 // along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>. 16 17 package whisperv6 18 19 import ( 20 "context" 21 "crypto/ecdsa" 22 "errors" 23 "fmt" 24 "sync" 25 "time" 26 27 "github.com/ethereum/go-ethereum/common" 28 "github.com/ethereum/go-ethereum/common/hexutil" 29 "github.com/ethereum/go-ethereum/crypto" 30 "github.com/ethereum/go-ethereum/log" 31 "github.com/ethereum/go-ethereum/p2p/discover" 32 "github.com/ethereum/go-ethereum/rpc" 33 ) 34 35 const ( 36 filterTimeout = 300 // filters are considered timeout out after filterTimeout seconds 37 ) 38 39 // List of errors 40 var ( 41 ErrSymAsym = errors.New("specify either a symmetric or an asymmetric key") 42 ErrInvalidSymmetricKey = errors.New("invalid symmetric key") 43 ErrInvalidPublicKey = errors.New("invalid public key") 44 ErrInvalidSigningPubKey = errors.New("invalid signing public key") 45 ErrTooLowPoW = errors.New("message rejected, PoW too low") 46 ErrNoTopics = errors.New("missing topic(s)") 47 ) 48 49 // PublicWhisperAPI provides the whisper RPC service that can be 50 // use publicly without security implications. 51 type PublicWhisperAPI struct { 52 w *Whisper 53 54 mu sync.Mutex 55 lastUsed map[string]time.Time // keeps track when a filter was polled for the last time. 56 } 57 58 // NewPublicWhisperAPI create a new RPC whisper service. 59 func NewPublicWhisperAPI(w *Whisper) *PublicWhisperAPI { 60 api := &PublicWhisperAPI{ 61 w: w, 62 lastUsed: make(map[string]time.Time), 63 } 64 65 go api.run() 66 return api 67 } 68 69 // run the api event loop. 70 // this loop deletes filter that have not been used within filterTimeout 71 func (api *PublicWhisperAPI) run() { 72 timeout := time.NewTicker(2 * time.Minute) 73 for { 74 <-timeout.C 75 76 api.mu.Lock() 77 for id, lastUsed := range api.lastUsed { 78 if time.Since(lastUsed).Seconds() >= filterTimeout { 79 delete(api.lastUsed, id) 80 if err := api.w.Unsubscribe(id); err != nil { 81 log.Error("could not unsubscribe whisper filter", "error", err) 82 } 83 log.Debug("delete whisper filter (timeout)", "id", id) 84 } 85 } 86 api.mu.Unlock() 87 } 88 } 89 90 // Version returns the Whisper sub-protocol version. 91 func (api *PublicWhisperAPI) Version(ctx context.Context) string { 92 return ProtocolVersionStr 93 } 94 95 // Info contains diagnostic information. 96 type Info struct { 97 Memory int `json:"memory"` // Memory size of the floating messages in bytes. 98 Messages int `json:"messages"` // Number of floating messages. 99 MinPow float64 `json:"minPow"` // Minimal accepted PoW 100 MaxMessageSize uint32 `json:"maxMessageSize"` // Maximum accepted message size 101 } 102 103 // Info returns diagnostic information about the whisper node. 104 func (api *PublicWhisperAPI) Info(ctx context.Context) Info { 105 stats := api.w.Stats() 106 return Info{ 107 Memory: stats.memoryUsed, 108 Messages: len(api.w.messageQueue) + len(api.w.p2pMsgQueue), 109 MinPow: api.w.MinPow(), 110 MaxMessageSize: api.w.MaxMessageSize(), 111 } 112 } 113 114 // SetMaxMessageSize sets the maximum message size that is accepted. 115 // Upper limit is defined by MaxMessageSize. 116 func (api *PublicWhisperAPI) SetMaxMessageSize(ctx context.Context, size uint32) (bool, error) { 117 return true, api.w.SetMaxMessageSize(size) 118 } 119 120 // SetMinPoW sets the minimum PoW, and notifies the peers. 121 func (api *PublicWhisperAPI) SetMinPoW(ctx context.Context, pow float64) (bool, error) { 122 return true, api.w.SetMinimumPoW(pow) 123 } 124 125 // SetBloomFilter sets the new value of bloom filter, and notifies the peers. 126 func (api *PublicWhisperAPI) SetBloomFilter(ctx context.Context, bloom hexutil.Bytes) (bool, error) { 127 return true, api.w.SetBloomFilter(bloom) 128 } 129 130 // MarkTrustedPeer marks a peer trusted, which will allow it to send historic (expired) messages. 131 // Note: This function is not adding new nodes, the node needs to exists as a peer. 132 func (api *PublicWhisperAPI) MarkTrustedPeer(ctx context.Context, enode string) (bool, error) { 133 n, err := discover.ParseNode(enode) 134 if err != nil { 135 return false, err 136 } 137 return true, api.w.AllowP2PMessagesFromPeer(n.ID[:]) 138 } 139 140 // NewKeyPair generates a new public and private key pair for message decryption and encryption. 141 // It returns an ID that can be used to refer to the keypair. 142 func (api *PublicWhisperAPI) NewKeyPair(ctx context.Context) (string, error) { 143 return api.w.NewKeyPair() 144 } 145 146 // AddPrivateKey imports the given private key. 147 func (api *PublicWhisperAPI) AddPrivateKey(ctx context.Context, privateKey hexutil.Bytes) (string, error) { 148 key, err := crypto.ToECDSA(privateKey) 149 if err != nil { 150 return "", err 151 } 152 return api.w.AddKeyPair(key) 153 } 154 155 // DeleteKeyPair removes the key with the given key if it exists. 156 func (api *PublicWhisperAPI) DeleteKeyPair(ctx context.Context, key string) (bool, error) { 157 if ok := api.w.DeleteKeyPair(key); ok { 158 return true, nil 159 } 160 return false, fmt.Errorf("key pair %s not found", key) 161 } 162 163 // HasKeyPair returns an indication if the node has a key pair that is associated with the given id. 164 func (api *PublicWhisperAPI) HasKeyPair(ctx context.Context, id string) bool { 165 return api.w.HasKeyPair(id) 166 } 167 168 // GetPublicKey returns the public key associated with the given key. The key is the hex 169 // encoded representation of a key in the form specified in section 4.3.6 of ANSI X9.62. 170 func (api *PublicWhisperAPI) GetPublicKey(ctx context.Context, id string) (hexutil.Bytes, error) { 171 key, err := api.w.GetPrivateKey(id) 172 if err != nil { 173 return hexutil.Bytes{}, err 174 } 175 return crypto.FromECDSAPub(&key.PublicKey), nil 176 } 177 178 // GetPrivateKey returns the private key associated with the given key. The key is the hex 179 // encoded representation of a key in the form specified in section 4.3.6 of ANSI X9.62. 180 func (api *PublicWhisperAPI) GetPrivateKey(ctx context.Context, id string) (hexutil.Bytes, error) { 181 key, err := api.w.GetPrivateKey(id) 182 if err != nil { 183 return hexutil.Bytes{}, err 184 } 185 return crypto.FromECDSA(key), nil 186 } 187 188 // NewSymKey generate a random symmetric key. 189 // It returns an ID that can be used to refer to the key. 190 // Can be used encrypting and decrypting messages where the key is known to both parties. 191 func (api *PublicWhisperAPI) NewSymKey(ctx context.Context) (string, error) { 192 return api.w.GenerateSymKey() 193 } 194 195 // AddSymKey import a symmetric key. 196 // It returns an ID that can be used to refer to the key. 197 // Can be used encrypting and decrypting messages where the key is known to both parties. 198 func (api *PublicWhisperAPI) AddSymKey(ctx context.Context, key hexutil.Bytes) (string, error) { 199 return api.w.AddSymKeyDirect([]byte(key)) 200 } 201 202 // GenerateSymKeyFromPassword derive a key from the given password, stores it, and returns its ID. 203 func (api *PublicWhisperAPI) GenerateSymKeyFromPassword(ctx context.Context, passwd string) (string, error) { 204 return api.w.AddSymKeyFromPassword(passwd) 205 } 206 207 // HasSymKey returns an indication if the node has a symmetric key associated with the given key. 208 func (api *PublicWhisperAPI) HasSymKey(ctx context.Context, id string) bool { 209 return api.w.HasSymKey(id) 210 } 211 212 // GetSymKey returns the symmetric key associated with the given id. 213 func (api *PublicWhisperAPI) GetSymKey(ctx context.Context, id string) (hexutil.Bytes, error) { 214 return api.w.GetSymKey(id) 215 } 216 217 // DeleteSymKey deletes the symmetric key that is associated with the given id. 218 func (api *PublicWhisperAPI) DeleteSymKey(ctx context.Context, id string) bool { 219 return api.w.DeleteSymKey(id) 220 } 221 222 //go:generate gencodec -type NewMessage -field-override newMessageOverride -out gen_newmessage_json.go 223 224 // NewMessage represents a new whisper message that is posted through the RPC. 225 type NewMessage struct { 226 SymKeyID string `json:"symKeyID"` 227 PublicKey []byte `json:"pubKey"` 228 Sig string `json:"sig"` 229 TTL uint32 `json:"ttl"` 230 Topic TopicType `json:"topic"` 231 Payload []byte `json:"payload"` 232 Padding []byte `json:"padding"` 233 PowTime uint32 `json:"powTime"` 234 PowTarget float64 `json:"powTarget"` 235 TargetPeer string `json:"targetPeer"` 236 } 237 238 type newMessageOverride struct { 239 PublicKey hexutil.Bytes 240 Payload hexutil.Bytes 241 Padding hexutil.Bytes 242 } 243 244 // Post a message on the Whisper network. 245 func (api *PublicWhisperAPI) Post(ctx context.Context, req NewMessage) (bool, error) { 246 var ( 247 symKeyGiven = len(req.SymKeyID) > 0 248 pubKeyGiven = len(req.PublicKey) > 0 249 err error 250 ) 251 252 // user must specify either a symmetric or an asymmetric key 253 if (symKeyGiven && pubKeyGiven) || (!symKeyGiven && !pubKeyGiven) { 254 return false, ErrSymAsym 255 } 256 257 params := &MessageParams{ 258 TTL: req.TTL, 259 Payload: req.Payload, 260 Padding: req.Padding, 261 WorkTime: req.PowTime, 262 PoW: req.PowTarget, 263 Topic: req.Topic, 264 } 265 266 // Set key that is used to sign the message 267 if len(req.Sig) > 0 { 268 if params.Src, err = api.w.GetPrivateKey(req.Sig); err != nil { 269 return false, err 270 } 271 } 272 273 // Set symmetric key that is used to encrypt the message 274 if symKeyGiven { 275 if params.Topic == (TopicType{}) { // topics are mandatory with symmetric encryption 276 return false, ErrNoTopics 277 } 278 if params.KeySym, err = api.w.GetSymKey(req.SymKeyID); err != nil { 279 return false, err 280 } 281 if !validateDataIntegrity(params.KeySym, aesKeyLength) { 282 return false, ErrInvalidSymmetricKey 283 } 284 } 285 286 // Set asymmetric key that is used to encrypt the message 287 if pubKeyGiven { 288 params.Dst = crypto.ToECDSAPub(req.PublicKey) 289 if !ValidatePublicKey(params.Dst) { 290 return false, ErrInvalidPublicKey 291 } 292 } 293 294 // encrypt and sent message 295 whisperMsg, err := newSentMessage(params) 296 if err != nil { 297 return false, err 298 } 299 300 env, err := whisperMsg.Wrap(params) 301 if err != nil { 302 return false, err 303 } 304 305 // send to specific node (skip PoW check) 306 if len(req.TargetPeer) > 0 { 307 n, err := discover.ParseNode(req.TargetPeer) 308 if err != nil { 309 return false, fmt.Errorf("failed to parse target peer: %s", err) 310 } 311 return true, api.w.SendP2PMessage(n.ID[:], env) 312 } 313 314 // ensure that the message PoW meets the node's minimum accepted PoW 315 if req.PowTarget < api.w.MinPow() { 316 return false, ErrTooLowPoW 317 } 318 319 return true, api.w.Send(env) 320 } 321 322 //go:generate gencodec -type Criteria -field-override criteriaOverride -out gen_criteria_json.go 323 324 // Criteria holds various filter options for inbound messages. 325 type Criteria struct { 326 SymKeyID string `json:"symKeyID"` 327 PrivateKeyID string `json:"privateKeyID"` 328 Sig []byte `json:"sig"` 329 MinPow float64 `json:"minPow"` 330 Topics []TopicType `json:"topics"` 331 AllowP2P bool `json:"allowP2P"` 332 } 333 334 type criteriaOverride struct { 335 Sig hexutil.Bytes 336 } 337 338 // Messages set up a subscription that fires events when messages arrive that match 339 // the given set of criteria. 340 func (api *PublicWhisperAPI) Messages(ctx context.Context, crit Criteria) (*rpc.Subscription, error) { 341 var ( 342 symKeyGiven = len(crit.SymKeyID) > 0 343 pubKeyGiven = len(crit.PrivateKeyID) > 0 344 err error 345 ) 346 347 // ensure that the RPC connection supports subscriptions 348 notifier, supported := rpc.NotifierFromContext(ctx) 349 if !supported { 350 return nil, rpc.ErrNotificationsUnsupported 351 } 352 353 // user must specify either a symmetric or an asymmetric key 354 if (symKeyGiven && pubKeyGiven) || (!symKeyGiven && !pubKeyGiven) { 355 return nil, ErrSymAsym 356 } 357 358 filter := Filter{ 359 PoW: crit.MinPow, 360 Messages: make(map[common.Hash]*ReceivedMessage), 361 AllowP2P: crit.AllowP2P, 362 } 363 364 if len(crit.Sig) > 0 { 365 filter.Src = crypto.ToECDSAPub(crit.Sig) 366 if !ValidatePublicKey(filter.Src) { 367 return nil, ErrInvalidSigningPubKey 368 } 369 } 370 371 for i, bt := range crit.Topics { 372 if len(bt) == 0 || len(bt) > 4 { 373 return nil, fmt.Errorf("subscribe: topic %d has wrong size: %d", i, len(bt)) 374 } 375 filter.Topics = append(filter.Topics, bt[:]) 376 } 377 378 // listen for message that are encrypted with the given symmetric key 379 if symKeyGiven { 380 if len(filter.Topics) == 0 { 381 return nil, ErrNoTopics 382 } 383 key, err := api.w.GetSymKey(crit.SymKeyID) 384 if err != nil { 385 return nil, err 386 } 387 if !validateDataIntegrity(key, aesKeyLength) { 388 return nil, ErrInvalidSymmetricKey 389 } 390 filter.KeySym = key 391 filter.SymKeyHash = crypto.Keccak256Hash(filter.KeySym) 392 } 393 394 // listen for messages that are encrypted with the given public key 395 if pubKeyGiven { 396 filter.KeyAsym, err = api.w.GetPrivateKey(crit.PrivateKeyID) 397 if err != nil || filter.KeyAsym == nil { 398 return nil, ErrInvalidPublicKey 399 } 400 } 401 402 id, err := api.w.Subscribe(&filter) 403 if err != nil { 404 return nil, err 405 } 406 407 // create subscription and start waiting for message events 408 rpcSub := notifier.CreateSubscription() 409 go func() { 410 // for now poll internally, refactor whisper internal for channel support 411 ticker := time.NewTicker(250 * time.Millisecond) 412 defer ticker.Stop() 413 414 for { 415 select { 416 case <-ticker.C: 417 if filter := api.w.GetFilter(id); filter != nil { 418 for _, rpcMessage := range toMessage(filter.Retrieve()) { 419 if err := notifier.Notify(rpcSub.ID, rpcMessage); err != nil { 420 log.Error("Failed to send notification", "err", err) 421 } 422 } 423 } 424 case <-rpcSub.Err(): 425 api.w.Unsubscribe(id) 426 return 427 case <-notifier.Closed(): 428 api.w.Unsubscribe(id) 429 return 430 } 431 } 432 }() 433 434 return rpcSub, nil 435 } 436 437 //go:generate gencodec -type Message -field-override messageOverride -out gen_message_json.go 438 439 // Message is the RPC representation of a whisper message. 440 type Message struct { 441 Sig []byte `json:"sig,omitempty"` 442 TTL uint32 `json:"ttl"` 443 Timestamp uint32 `json:"timestamp"` 444 Topic TopicType `json:"topic"` 445 Payload []byte `json:"payload"` 446 Padding []byte `json:"padding"` 447 PoW float64 `json:"pow"` 448 Hash []byte `json:"hash"` 449 Dst []byte `json:"recipientPublicKey,omitempty"` 450 } 451 452 type messageOverride struct { 453 Sig hexutil.Bytes 454 Payload hexutil.Bytes 455 Padding hexutil.Bytes 456 Hash hexutil.Bytes 457 Dst hexutil.Bytes 458 } 459 460 // ToWhisperMessage converts an internal message into an API version. 461 func ToWhisperMessage(message *ReceivedMessage) *Message { 462 msg := Message{ 463 Payload: message.Payload, 464 Padding: message.Padding, 465 Timestamp: message.Sent, 466 TTL: message.TTL, 467 PoW: message.PoW, 468 Hash: message.EnvelopeHash.Bytes(), 469 Topic: message.Topic, 470 } 471 472 if message.Dst != nil { 473 b := crypto.FromECDSAPub(message.Dst) 474 if b != nil { 475 msg.Dst = b 476 } 477 } 478 479 if isMessageSigned(message.Raw[0]) { 480 b := crypto.FromECDSAPub(message.SigToPubKey()) 481 if b != nil { 482 msg.Sig = b 483 } 484 } 485 486 return &msg 487 } 488 489 // toMessage converts a set of messages to its RPC representation. 490 func toMessage(messages []*ReceivedMessage) []*Message { 491 msgs := make([]*Message, len(messages)) 492 for i, msg := range messages { 493 msgs[i] = ToWhisperMessage(msg) 494 } 495 return msgs 496 } 497 498 // GetFilterMessages returns the messages that match the filter criteria and 499 // are received between the last poll and now. 500 func (api *PublicWhisperAPI) GetFilterMessages(id string) ([]*Message, error) { 501 api.mu.Lock() 502 f := api.w.GetFilter(id) 503 if f == nil { 504 api.mu.Unlock() 505 return nil, fmt.Errorf("filter not found") 506 } 507 api.lastUsed[id] = time.Now() 508 api.mu.Unlock() 509 510 receivedMessages := f.Retrieve() 511 messages := make([]*Message, 0, len(receivedMessages)) 512 for _, msg := range receivedMessages { 513 messages = append(messages, ToWhisperMessage(msg)) 514 } 515 516 return messages, nil 517 } 518 519 // DeleteMessageFilter deletes a filter. 520 func (api *PublicWhisperAPI) DeleteMessageFilter(id string) (bool, error) { 521 api.mu.Lock() 522 defer api.mu.Unlock() 523 524 delete(api.lastUsed, id) 525 return true, api.w.Unsubscribe(id) 526 } 527 528 // NewMessageFilter creates a new filter that can be used to poll for 529 // (new) messages that satisfy the given criteria. 530 func (api *PublicWhisperAPI) NewMessageFilter(req Criteria) (string, error) { 531 var ( 532 src *ecdsa.PublicKey 533 keySym []byte 534 keyAsym *ecdsa.PrivateKey 535 topics [][]byte 536 537 symKeyGiven = len(req.SymKeyID) > 0 538 asymKeyGiven = len(req.PrivateKeyID) > 0 539 540 err error 541 ) 542 543 // user must specify either a symmetric or an asymmetric key 544 if (symKeyGiven && asymKeyGiven) || (!symKeyGiven && !asymKeyGiven) { 545 return "", ErrSymAsym 546 } 547 548 if len(req.Sig) > 0 { 549 src = crypto.ToECDSAPub(req.Sig) 550 if !ValidatePublicKey(src) { 551 return "", ErrInvalidSigningPubKey 552 } 553 } 554 555 if symKeyGiven { 556 if keySym, err = api.w.GetSymKey(req.SymKeyID); err != nil { 557 return "", err 558 } 559 if !validateDataIntegrity(keySym, aesKeyLength) { 560 return "", ErrInvalidSymmetricKey 561 } 562 } 563 564 if asymKeyGiven { 565 if keyAsym, err = api.w.GetPrivateKey(req.PrivateKeyID); err != nil { 566 return "", err 567 } 568 } 569 570 if len(req.Topics) > 0 { 571 topics = make([][]byte, 0, len(req.Topics)) 572 for _, topic := range req.Topics { 573 topics = append(topics, topic[:]) 574 } 575 } 576 577 f := &Filter{ 578 Src: src, 579 KeySym: keySym, 580 KeyAsym: keyAsym, 581 PoW: req.MinPow, 582 AllowP2P: req.AllowP2P, 583 Topics: topics, 584 Messages: make(map[common.Hash]*ReceivedMessage), 585 } 586 587 id, err := api.w.Subscribe(f) 588 if err != nil { 589 return "", err 590 } 591 592 api.mu.Lock() 593 api.lastUsed[id] = time.Now() 594 api.mu.Unlock() 595 596 return id, nil 597 }