github.com/samgwo/go-ethereum@v1.8.2-0.20180302101319-49bcb5fbd55e/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 return api 65 } 66 67 // Version returns the Whisper sub-protocol version. 68 func (api *PublicWhisperAPI) Version(ctx context.Context) string { 69 return ProtocolVersionStr 70 } 71 72 // Info contains diagnostic information. 73 type Info struct { 74 Memory int `json:"memory"` // Memory size of the floating messages in bytes. 75 Messages int `json:"messages"` // Number of floating messages. 76 MinPow float64 `json:"minPow"` // Minimal accepted PoW 77 MaxMessageSize uint32 `json:"maxMessageSize"` // Maximum accepted message size 78 } 79 80 // Info returns diagnostic information about the whisper node. 81 func (api *PublicWhisperAPI) Info(ctx context.Context) Info { 82 stats := api.w.Stats() 83 return Info{ 84 Memory: stats.memoryUsed, 85 Messages: len(api.w.messageQueue) + len(api.w.p2pMsgQueue), 86 MinPow: api.w.MinPow(), 87 MaxMessageSize: api.w.MaxMessageSize(), 88 } 89 } 90 91 // SetMaxMessageSize sets the maximum message size that is accepted. 92 // Upper limit is defined by MaxMessageSize. 93 func (api *PublicWhisperAPI) SetMaxMessageSize(ctx context.Context, size uint32) (bool, error) { 94 return true, api.w.SetMaxMessageSize(size) 95 } 96 97 // SetMinPoW sets the minimum PoW, and notifies the peers. 98 func (api *PublicWhisperAPI) SetMinPoW(ctx context.Context, pow float64) (bool, error) { 99 return true, api.w.SetMinimumPoW(pow) 100 } 101 102 // SetBloomFilter sets the new value of bloom filter, and notifies the peers. 103 func (api *PublicWhisperAPI) SetBloomFilter(ctx context.Context, bloom hexutil.Bytes) (bool, error) { 104 return true, api.w.SetBloomFilter(bloom) 105 } 106 107 // MarkTrustedPeer marks a peer trusted, which will allow it to send historic (expired) messages. 108 // Note: This function is not adding new nodes, the node needs to exists as a peer. 109 func (api *PublicWhisperAPI) MarkTrustedPeer(ctx context.Context, enode string) (bool, error) { 110 n, err := discover.ParseNode(enode) 111 if err != nil { 112 return false, err 113 } 114 return true, api.w.AllowP2PMessagesFromPeer(n.ID[:]) 115 } 116 117 // NewKeyPair generates a new public and private key pair for message decryption and encryption. 118 // It returns an ID that can be used to refer to the keypair. 119 func (api *PublicWhisperAPI) NewKeyPair(ctx context.Context) (string, error) { 120 return api.w.NewKeyPair() 121 } 122 123 // AddPrivateKey imports the given private key. 124 func (api *PublicWhisperAPI) AddPrivateKey(ctx context.Context, privateKey hexutil.Bytes) (string, error) { 125 key, err := crypto.ToECDSA(privateKey) 126 if err != nil { 127 return "", err 128 } 129 return api.w.AddKeyPair(key) 130 } 131 132 // DeleteKeyPair removes the key with the given key if it exists. 133 func (api *PublicWhisperAPI) DeleteKeyPair(ctx context.Context, key string) (bool, error) { 134 if ok := api.w.DeleteKeyPair(key); ok { 135 return true, nil 136 } 137 return false, fmt.Errorf("key pair %s not found", key) 138 } 139 140 // HasKeyPair returns an indication if the node has a key pair that is associated with the given id. 141 func (api *PublicWhisperAPI) HasKeyPair(ctx context.Context, id string) bool { 142 return api.w.HasKeyPair(id) 143 } 144 145 // GetPublicKey returns the public key associated with the given key. The key is the hex 146 // encoded representation of a key in the form specified in section 4.3.6 of ANSI X9.62. 147 func (api *PublicWhisperAPI) GetPublicKey(ctx context.Context, id string) (hexutil.Bytes, error) { 148 key, err := api.w.GetPrivateKey(id) 149 if err != nil { 150 return hexutil.Bytes{}, err 151 } 152 return crypto.FromECDSAPub(&key.PublicKey), nil 153 } 154 155 // GetPrivateKey returns the private key associated with the given key. The key is the hex 156 // encoded representation of a key in the form specified in section 4.3.6 of ANSI X9.62. 157 func (api *PublicWhisperAPI) GetPrivateKey(ctx context.Context, id string) (hexutil.Bytes, error) { 158 key, err := api.w.GetPrivateKey(id) 159 if err != nil { 160 return hexutil.Bytes{}, err 161 } 162 return crypto.FromECDSA(key), nil 163 } 164 165 // NewSymKey generate a random symmetric key. 166 // It returns an ID that can be used to refer to the key. 167 // Can be used encrypting and decrypting messages where the key is known to both parties. 168 func (api *PublicWhisperAPI) NewSymKey(ctx context.Context) (string, error) { 169 return api.w.GenerateSymKey() 170 } 171 172 // AddSymKey import a symmetric key. 173 // It returns an ID that can be used to refer to the key. 174 // Can be used encrypting and decrypting messages where the key is known to both parties. 175 func (api *PublicWhisperAPI) AddSymKey(ctx context.Context, key hexutil.Bytes) (string, error) { 176 return api.w.AddSymKeyDirect([]byte(key)) 177 } 178 179 // GenerateSymKeyFromPassword derive a key from the given password, stores it, and returns its ID. 180 func (api *PublicWhisperAPI) GenerateSymKeyFromPassword(ctx context.Context, passwd string) (string, error) { 181 return api.w.AddSymKeyFromPassword(passwd) 182 } 183 184 // HasSymKey returns an indication if the node has a symmetric key associated with the given key. 185 func (api *PublicWhisperAPI) HasSymKey(ctx context.Context, id string) bool { 186 return api.w.HasSymKey(id) 187 } 188 189 // GetSymKey returns the symmetric key associated with the given id. 190 func (api *PublicWhisperAPI) GetSymKey(ctx context.Context, id string) (hexutil.Bytes, error) { 191 return api.w.GetSymKey(id) 192 } 193 194 // DeleteSymKey deletes the symmetric key that is associated with the given id. 195 func (api *PublicWhisperAPI) DeleteSymKey(ctx context.Context, id string) bool { 196 return api.w.DeleteSymKey(id) 197 } 198 199 // MakeLightClient turns the node into light client, which does not forward 200 // any incoming messages, and sends only messages originated in this node. 201 func (api *PublicWhisperAPI) MakeLightClient(ctx context.Context) bool { 202 api.w.lightClient = true 203 return api.w.lightClient 204 } 205 206 // CancelLightClient cancels light client mode. 207 func (api *PublicWhisperAPI) CancelLightClient(ctx context.Context) bool { 208 api.w.lightClient = false 209 return !api.w.lightClient 210 } 211 212 //go:generate gencodec -type NewMessage -field-override newMessageOverride -out gen_newmessage_json.go 213 214 // NewMessage represents a new whisper message that is posted through the RPC. 215 type NewMessage struct { 216 SymKeyID string `json:"symKeyID"` 217 PublicKey []byte `json:"pubKey"` 218 Sig string `json:"sig"` 219 TTL uint32 `json:"ttl"` 220 Topic TopicType `json:"topic"` 221 Payload []byte `json:"payload"` 222 Padding []byte `json:"padding"` 223 PowTime uint32 `json:"powTime"` 224 PowTarget float64 `json:"powTarget"` 225 TargetPeer string `json:"targetPeer"` 226 } 227 228 type newMessageOverride struct { 229 PublicKey hexutil.Bytes 230 Payload hexutil.Bytes 231 Padding hexutil.Bytes 232 } 233 234 // Post a message on the Whisper network. 235 func (api *PublicWhisperAPI) Post(ctx context.Context, req NewMessage) (bool, error) { 236 var ( 237 symKeyGiven = len(req.SymKeyID) > 0 238 pubKeyGiven = len(req.PublicKey) > 0 239 err error 240 ) 241 242 // user must specify either a symmetric or an asymmetric key 243 if (symKeyGiven && pubKeyGiven) || (!symKeyGiven && !pubKeyGiven) { 244 return false, ErrSymAsym 245 } 246 247 params := &MessageParams{ 248 TTL: req.TTL, 249 Payload: req.Payload, 250 Padding: req.Padding, 251 WorkTime: req.PowTime, 252 PoW: req.PowTarget, 253 Topic: req.Topic, 254 } 255 256 // Set key that is used to sign the message 257 if len(req.Sig) > 0 { 258 if params.Src, err = api.w.GetPrivateKey(req.Sig); err != nil { 259 return false, err 260 } 261 } 262 263 // Set symmetric key that is used to encrypt the message 264 if symKeyGiven { 265 if params.Topic == (TopicType{}) { // topics are mandatory with symmetric encryption 266 return false, ErrNoTopics 267 } 268 if params.KeySym, err = api.w.GetSymKey(req.SymKeyID); err != nil { 269 return false, err 270 } 271 if !validateDataIntegrity(params.KeySym, aesKeyLength) { 272 return false, ErrInvalidSymmetricKey 273 } 274 } 275 276 // Set asymmetric key that is used to encrypt the message 277 if pubKeyGiven { 278 params.Dst = crypto.ToECDSAPub(req.PublicKey) 279 if !ValidatePublicKey(params.Dst) { 280 return false, ErrInvalidPublicKey 281 } 282 } 283 284 // encrypt and sent message 285 whisperMsg, err := NewSentMessage(params) 286 if err != nil { 287 return false, err 288 } 289 290 env, err := whisperMsg.Wrap(params) 291 if err != nil { 292 return false, err 293 } 294 295 // send to specific node (skip PoW check) 296 if len(req.TargetPeer) > 0 { 297 n, err := discover.ParseNode(req.TargetPeer) 298 if err != nil { 299 return false, fmt.Errorf("failed to parse target peer: %s", err) 300 } 301 return true, api.w.SendP2PMessage(n.ID[:], env) 302 } 303 304 // ensure that the message PoW meets the node's minimum accepted PoW 305 if req.PowTarget < api.w.MinPow() { 306 return false, ErrTooLowPoW 307 } 308 309 return true, api.w.Send(env) 310 } 311 312 //go:generate gencodec -type Criteria -field-override criteriaOverride -out gen_criteria_json.go 313 314 // Criteria holds various filter options for inbound messages. 315 type Criteria struct { 316 SymKeyID string `json:"symKeyID"` 317 PrivateKeyID string `json:"privateKeyID"` 318 Sig []byte `json:"sig"` 319 MinPow float64 `json:"minPow"` 320 Topics []TopicType `json:"topics"` 321 AllowP2P bool `json:"allowP2P"` 322 } 323 324 type criteriaOverride struct { 325 Sig hexutil.Bytes 326 } 327 328 // Messages set up a subscription that fires events when messages arrive that match 329 // the given set of criteria. 330 func (api *PublicWhisperAPI) Messages(ctx context.Context, crit Criteria) (*rpc.Subscription, error) { 331 var ( 332 symKeyGiven = len(crit.SymKeyID) > 0 333 pubKeyGiven = len(crit.PrivateKeyID) > 0 334 err error 335 ) 336 337 // ensure that the RPC connection supports subscriptions 338 notifier, supported := rpc.NotifierFromContext(ctx) 339 if !supported { 340 return nil, rpc.ErrNotificationsUnsupported 341 } 342 343 // user must specify either a symmetric or an asymmetric key 344 if (symKeyGiven && pubKeyGiven) || (!symKeyGiven && !pubKeyGiven) { 345 return nil, ErrSymAsym 346 } 347 348 filter := Filter{ 349 PoW: crit.MinPow, 350 Messages: make(map[common.Hash]*ReceivedMessage), 351 AllowP2P: crit.AllowP2P, 352 } 353 354 if len(crit.Sig) > 0 { 355 filter.Src = crypto.ToECDSAPub(crit.Sig) 356 if !ValidatePublicKey(filter.Src) { 357 return nil, ErrInvalidSigningPubKey 358 } 359 } 360 361 for i, bt := range crit.Topics { 362 if len(bt) == 0 || len(bt) > 4 { 363 return nil, fmt.Errorf("subscribe: topic %d has wrong size: %d", i, len(bt)) 364 } 365 filter.Topics = append(filter.Topics, bt[:]) 366 } 367 368 // listen for message that are encrypted with the given symmetric key 369 if symKeyGiven { 370 if len(filter.Topics) == 0 { 371 return nil, ErrNoTopics 372 } 373 key, err := api.w.GetSymKey(crit.SymKeyID) 374 if err != nil { 375 return nil, err 376 } 377 if !validateDataIntegrity(key, aesKeyLength) { 378 return nil, ErrInvalidSymmetricKey 379 } 380 filter.KeySym = key 381 filter.SymKeyHash = crypto.Keccak256Hash(filter.KeySym) 382 } 383 384 // listen for messages that are encrypted with the given public key 385 if pubKeyGiven { 386 filter.KeyAsym, err = api.w.GetPrivateKey(crit.PrivateKeyID) 387 if err != nil || filter.KeyAsym == nil { 388 return nil, ErrInvalidPublicKey 389 } 390 } 391 392 id, err := api.w.Subscribe(&filter) 393 if err != nil { 394 return nil, err 395 } 396 397 // create subscription and start waiting for message events 398 rpcSub := notifier.CreateSubscription() 399 go func() { 400 // for now poll internally, refactor whisper internal for channel support 401 ticker := time.NewTicker(250 * time.Millisecond) 402 defer ticker.Stop() 403 404 for { 405 select { 406 case <-ticker.C: 407 if filter := api.w.GetFilter(id); filter != nil { 408 for _, rpcMessage := range toMessage(filter.Retrieve()) { 409 if err := notifier.Notify(rpcSub.ID, rpcMessage); err != nil { 410 log.Error("Failed to send notification", "err", err) 411 } 412 } 413 } 414 case <-rpcSub.Err(): 415 api.w.Unsubscribe(id) 416 return 417 case <-notifier.Closed(): 418 api.w.Unsubscribe(id) 419 return 420 } 421 } 422 }() 423 424 return rpcSub, nil 425 } 426 427 //go:generate gencodec -type Message -field-override messageOverride -out gen_message_json.go 428 429 // Message is the RPC representation of a whisper message. 430 type Message struct { 431 Sig []byte `json:"sig,omitempty"` 432 TTL uint32 `json:"ttl"` 433 Timestamp uint32 `json:"timestamp"` 434 Topic TopicType `json:"topic"` 435 Payload []byte `json:"payload"` 436 Padding []byte `json:"padding"` 437 PoW float64 `json:"pow"` 438 Hash []byte `json:"hash"` 439 Dst []byte `json:"recipientPublicKey,omitempty"` 440 } 441 442 type messageOverride struct { 443 Sig hexutil.Bytes 444 Payload hexutil.Bytes 445 Padding hexutil.Bytes 446 Hash hexutil.Bytes 447 Dst hexutil.Bytes 448 } 449 450 // ToWhisperMessage converts an internal message into an API version. 451 func ToWhisperMessage(message *ReceivedMessage) *Message { 452 msg := Message{ 453 Payload: message.Payload, 454 Padding: message.Padding, 455 Timestamp: message.Sent, 456 TTL: message.TTL, 457 PoW: message.PoW, 458 Hash: message.EnvelopeHash.Bytes(), 459 Topic: message.Topic, 460 } 461 462 if message.Dst != nil { 463 b := crypto.FromECDSAPub(message.Dst) 464 if b != nil { 465 msg.Dst = b 466 } 467 } 468 469 if isMessageSigned(message.Raw[0]) { 470 b := crypto.FromECDSAPub(message.SigToPubKey()) 471 if b != nil { 472 msg.Sig = b 473 } 474 } 475 476 return &msg 477 } 478 479 // toMessage converts a set of messages to its RPC representation. 480 func toMessage(messages []*ReceivedMessage) []*Message { 481 msgs := make([]*Message, len(messages)) 482 for i, msg := range messages { 483 msgs[i] = ToWhisperMessage(msg) 484 } 485 return msgs 486 } 487 488 // GetFilterMessages returns the messages that match the filter criteria and 489 // are received between the last poll and now. 490 func (api *PublicWhisperAPI) GetFilterMessages(id string) ([]*Message, error) { 491 api.mu.Lock() 492 f := api.w.GetFilter(id) 493 if f == nil { 494 api.mu.Unlock() 495 return nil, fmt.Errorf("filter not found") 496 } 497 api.lastUsed[id] = time.Now() 498 api.mu.Unlock() 499 500 receivedMessages := f.Retrieve() 501 messages := make([]*Message, 0, len(receivedMessages)) 502 for _, msg := range receivedMessages { 503 messages = append(messages, ToWhisperMessage(msg)) 504 } 505 506 return messages, nil 507 } 508 509 // DeleteMessageFilter deletes a filter. 510 func (api *PublicWhisperAPI) DeleteMessageFilter(id string) (bool, error) { 511 api.mu.Lock() 512 defer api.mu.Unlock() 513 514 delete(api.lastUsed, id) 515 return true, api.w.Unsubscribe(id) 516 } 517 518 // NewMessageFilter creates a new filter that can be used to poll for 519 // (new) messages that satisfy the given criteria. 520 func (api *PublicWhisperAPI) NewMessageFilter(req Criteria) (string, error) { 521 var ( 522 src *ecdsa.PublicKey 523 keySym []byte 524 keyAsym *ecdsa.PrivateKey 525 topics [][]byte 526 527 symKeyGiven = len(req.SymKeyID) > 0 528 asymKeyGiven = len(req.PrivateKeyID) > 0 529 530 err error 531 ) 532 533 // user must specify either a symmetric or an asymmetric key 534 if (symKeyGiven && asymKeyGiven) || (!symKeyGiven && !asymKeyGiven) { 535 return "", ErrSymAsym 536 } 537 538 if len(req.Sig) > 0 { 539 src = crypto.ToECDSAPub(req.Sig) 540 if !ValidatePublicKey(src) { 541 return "", ErrInvalidSigningPubKey 542 } 543 } 544 545 if symKeyGiven { 546 if keySym, err = api.w.GetSymKey(req.SymKeyID); err != nil { 547 return "", err 548 } 549 if !validateDataIntegrity(keySym, aesKeyLength) { 550 return "", ErrInvalidSymmetricKey 551 } 552 } 553 554 if asymKeyGiven { 555 if keyAsym, err = api.w.GetPrivateKey(req.PrivateKeyID); err != nil { 556 return "", err 557 } 558 } 559 560 if len(req.Topics) > 0 { 561 topics = make([][]byte, 0, len(req.Topics)) 562 for _, topic := range req.Topics { 563 topics = append(topics, topic[:]) 564 } 565 } 566 567 f := &Filter{ 568 Src: src, 569 KeySym: keySym, 570 KeyAsym: keyAsym, 571 PoW: req.MinPow, 572 AllowP2P: req.AllowP2P, 573 Topics: topics, 574 Messages: make(map[common.Hash]*ReceivedMessage), 575 } 576 577 id, err := api.w.Subscribe(f) 578 if err != nil { 579 return "", err 580 } 581 582 api.mu.Lock() 583 api.lastUsed[id] = time.Now() 584 api.mu.Unlock() 585 586 return id, nil 587 }