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Diffstat (limited to 'whisper/api.go')
-rw-r--r-- | whisper/api.go | 413 |
1 files changed, 413 insertions, 0 deletions
diff --git a/whisper/api.go b/whisper/api.go new file mode 100644 index 000000000..16f8bd329 --- /dev/null +++ b/whisper/api.go @@ -0,0 +1,413 @@ +// Copyright 2015 The go-ethereum Authors +// This file is part of go-ethereum. +// +// go-ethereum is free software: you can redistribute it and/or modify +// it under the terms of the GNU General Public License as published by +// the Free Software Foundation, either version 3 of the License, or +// (at your option) any later version. +// +// go-ethereum is distributed in the hope that it will be useful, +// but WITHOUT ANY WARRANTY; without even the implied warranty of +// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +// GNU General Public License for more details. +// +// You should have received a copy of the GNU General Public License +// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>. + +package whisper + +import ( + "encoding/json" + "fmt" + "sync" + "time" + + "github.com/ethereum/go-ethereum/common" + "github.com/ethereum/go-ethereum/crypto" + rpc "github.com/ethereum/go-ethereum/rpc/v2" +) + +// PublicWhisperAPI provides the whisper RPC service. +type PublicWhisperAPI struct { + w *Whisper + + messagesMu sync.RWMutex + messages map[int]*whisperFilter +} + +type whisperOfflineError struct{} + +func (e *whisperOfflineError) Error() string { + return "whisper is offline" +} + +// whisperOffLineErr is returned when the node doesn't offer the shh service. +var whisperOffLineErr = new(whisperOfflineError) + +// NewPublicWhisperAPI create a new RPC whisper service. +func NewPublicWhisperAPI(w *Whisper) *PublicWhisperAPI { + return &PublicWhisperAPI{w: w, messages: make(map[int]*whisperFilter)} +} + +// Version returns the Whisper version this node offers. +func (s *PublicWhisperAPI) Version() (*rpc.HexNumber, error) { + if s.w == nil { + return rpc.NewHexNumber(0), whisperOffLineErr + } + return rpc.NewHexNumber(s.w.Version()), nil +} + +// HasIdentity checks if the the whisper node is configured with the private key +// of the specified public pair. +func (s *PublicWhisperAPI) HasIdentity(identity string) (bool, error) { + if s.w == nil { + return false, whisperOffLineErr + } + return s.w.HasIdentity(crypto.ToECDSAPub(common.FromHex(identity))), nil +} + +// NewIdentity generates a new cryptographic identity for the client, and injects +// it into the known identities for message decryption. +func (s *PublicWhisperAPI) NewIdentity() (string, error) { + if s.w == nil { + return "", whisperOffLineErr + } + + identity := s.w.NewIdentity() + return common.ToHex(crypto.FromECDSAPub(&identity.PublicKey)), nil +} + +type NewFilterArgs struct { + To string + From string + Topics [][][]byte +} + +// NewWhisperFilter creates and registers a new message filter to watch for inbound whisper messages. +func (s *PublicWhisperAPI) NewFilter(args *NewFilterArgs) (*rpc.HexNumber, error) { + if s.w == nil { + return nil, whisperOffLineErr + } + + var id int + filter := Filter{ + To: crypto.ToECDSAPub(common.FromHex(args.To)), + From: crypto.ToECDSAPub(common.FromHex(args.From)), + Topics: NewFilterTopics(args.Topics...), + Fn: func(message *Message) { + wmsg := NewWhisperMessage(message) + s.messagesMu.RLock() // Only read lock to the filter pool + defer s.messagesMu.RUnlock() + if s.messages[id] != nil { + s.messages[id].insert(wmsg) + } + }, + } + + id = s.w.Watch(filter) + + s.messagesMu.Lock() + s.messages[id] = newWhisperFilter(id, s.w) + s.messagesMu.Unlock() + + return rpc.NewHexNumber(id), nil +} + +// GetFilterChanges retrieves all the new messages matched by a filter since the last retrieval. +func (s *PublicWhisperAPI) GetFilterChanges(filterId rpc.HexNumber) []WhisperMessage { + s.messagesMu.RLock() + defer s.messagesMu.RUnlock() + + if s.messages[filterId.Int()] != nil { + if changes := s.messages[filterId.Int()].retrieve(); changes != nil { + return changes + } + } + return returnWhisperMessages(nil) +} + +// UninstallFilter disables and removes an existing filter. +func (s *PublicWhisperAPI) UninstallFilter(filterId rpc.HexNumber) bool { + s.messagesMu.Lock() + defer s.messagesMu.Unlock() + + if _, ok := s.messages[filterId.Int()]; ok { + delete(s.messages, filterId.Int()) + return true + } + return false +} + +// GetMessages retrieves all the known messages that match a specific filter. +func (s *PublicWhisperAPI) GetMessages(filterId rpc.HexNumber) []WhisperMessage { + // Retrieve all the cached messages matching a specific, existing filter + s.messagesMu.RLock() + defer s.messagesMu.RUnlock() + + var messages []*Message + if s.messages[filterId.Int()] != nil { + messages = s.messages[filterId.Int()].messages() + } + + return returnWhisperMessages(messages) +} + +// returnWhisperMessages converts aNhisper message to a RPC whisper message. +func returnWhisperMessages(messages []*Message) []WhisperMessage { + msgs := make([]WhisperMessage, len(messages)) + for i, msg := range messages { + msgs[i] = NewWhisperMessage(msg) + } + return msgs +} + +type PostArgs struct { + From string `json:"from"` + To string `json:"to"` + Topics [][]byte `json:"topics"` + Payload string `json:"payload"` + Priority int64 `json:"priority"` + TTL int64 `json:"ttl"` +} + +// Post injects a message into the whisper network for distribution. +func (s *PublicWhisperAPI) Post(args *PostArgs) (bool, error) { + if s.w == nil { + return false, whisperOffLineErr + } + + // construct whisper message with transmission options + message := NewMessage(common.FromHex(args.Payload)) + options := Options{ + To: crypto.ToECDSAPub(common.FromHex(args.To)), + TTL: time.Duration(args.TTL) * time.Second, + Topics: NewTopics(args.Topics...), + } + + // set sender identity + if len(args.From) > 0 { + if key := s.w.GetIdentity(crypto.ToECDSAPub(common.FromHex(args.From))); key != nil { + options.From = key + } else { + return false, fmt.Errorf("unknown identity to send from: %s", args.From) + } + } + + // Wrap and send the message + pow := time.Duration(args.Priority) * time.Millisecond + envelope, err := message.Wrap(pow, options) + if err != nil { + return false, err + } + + return true, s.w.Send(envelope) +} + +// WhisperMessage is the RPC representation of a whisper message. +type WhisperMessage struct { + ref *Message + + Payload string `json:"payload"` + To string `json:"to"` + From string `json:"from"` + Sent int64 `json:"sent"` + TTL int64 `json:"ttl"` + Hash string `json:"hash"` +} + +func (args *PostArgs) UnmarshalJSON(data []byte) (err error) { + var obj struct { + From string `json:"from"` + To string `json:"to"` + Topics []string `json:"topics"` + Payload string `json:"payload"` + Priority rpc.HexNumber `json:"priority"` + TTL rpc.HexNumber `json:"ttl"` + } + + if err := json.Unmarshal(data, &obj); err != nil { + return err + } + + args.From = obj.From + args.To = obj.To + args.Payload = obj.Payload + args.Priority = obj.Priority.Int64() + args.TTL = obj.TTL.Int64() + + // decode topic strings + args.Topics = make([][]byte, len(obj.Topics)) + for i, topic := range obj.Topics { + args.Topics[i] = common.FromHex(topic) + } + + return nil +} + +// UnmarshalJSON implements the json.Unmarshaler interface, invoked to convert a +// JSON message blob into a WhisperFilterArgs structure. +func (args *NewFilterArgs) UnmarshalJSON(b []byte) (err error) { + // Unmarshal the JSON message and sanity check + var obj struct { + To interface{} `json:"to"` + From interface{} `json:"from"` + Topics interface{} `json:"topics"` + } + if err := json.Unmarshal(b, &obj); err != nil { + return err + } + + // Retrieve the simple data contents of the filter arguments + if obj.To == nil { + args.To = "" + } else { + argstr, ok := obj.To.(string) + if !ok { + return fmt.Errorf("to is not a string") + } + args.To = argstr + } + if obj.From == nil { + args.From = "" + } else { + argstr, ok := obj.From.(string) + if !ok { + return fmt.Errorf("from is not a string") + } + args.From = argstr + } + // Construct the nested topic array + if obj.Topics != nil { + // Make sure we have an actual topic array + list, ok := obj.Topics.([]interface{}) + if !ok { + return fmt.Errorf("topics is not an array") + } + // Iterate over each topic and handle nil, string or array + topics := make([][]string, len(list)) + for idx, field := range list { + switch value := field.(type) { + case nil: + topics[idx] = []string{} + + case string: + topics[idx] = []string{value} + + case []interface{}: + topics[idx] = make([]string, len(value)) + for i, nested := range value { + switch value := nested.(type) { + case nil: + topics[idx][i] = "" + + case string: + topics[idx][i] = value + + default: + return fmt.Errorf("topic[%d][%d] is not a string", idx, i) + } + } + default: + return fmt.Errorf("topic[%d] not a string or array", idx) + } + } + + topicsDecoded := make([][][]byte, len(topics)) + for i, condition := range topics { + topicsDecoded[i] = make([][]byte, len(condition)) + for j, topic := range condition { + topicsDecoded[i][j] = common.FromHex(topic) + } + } + + args.Topics = topicsDecoded + } + return nil +} + +// whisperFilter is the message cache matching a specific filter, accumulating +// inbound messages until the are requested by the client. +type whisperFilter struct { + id int // Filter identifier for old message retrieval + ref *Whisper // Whisper reference for old message retrieval + + cache []WhisperMessage // Cache of messages not yet polled + skip map[common.Hash]struct{} // List of retrieved messages to avoid duplication + update time.Time // Time of the last message query + + lock sync.RWMutex // Lock protecting the filter internals +} + +// messages retrieves all the cached messages from the entire pool matching the +// filter, resetting the filter's change buffer. +func (w *whisperFilter) messages() []*Message { + w.lock.Lock() + defer w.lock.Unlock() + + w.cache = nil + w.update = time.Now() + + w.skip = make(map[common.Hash]struct{}) + messages := w.ref.Messages(w.id) + for _, message := range messages { + w.skip[message.Hash] = struct{}{} + } + return messages +} + +// insert injects a new batch of messages into the filter cache. +func (w *whisperFilter) insert(messages ...WhisperMessage) { + w.lock.Lock() + defer w.lock.Unlock() + + for _, message := range messages { + if _, ok := w.skip[message.ref.Hash]; !ok { + w.cache = append(w.cache, messages...) + } + } +} + +// retrieve fetches all the cached messages from the filter. +func (w *whisperFilter) retrieve() (messages []WhisperMessage) { + w.lock.Lock() + defer w.lock.Unlock() + + messages, w.cache = w.cache, nil + w.update = time.Now() + + return +} + +// activity returns the last time instance when client requests were executed on +// the filter. +func (w *whisperFilter) activity() time.Time { + w.lock.RLock() + defer w.lock.RUnlock() + + return w.update +} + +// newWhisperFilter creates a new serialized, poll based whisper topic filter. +func newWhisperFilter(id int, ref *Whisper) *whisperFilter { + return &whisperFilter{ + id: id, + ref: ref, + + update: time.Now(), + skip: make(map[common.Hash]struct{}), + } +} + +// NewWhisperMessage converts an internal message into an API version. +func NewWhisperMessage(message *Message) WhisperMessage { + return WhisperMessage{ + ref: message, + + Payload: common.ToHex(message.Payload), + From: common.ToHex(crypto.FromECDSAPub(message.Recover())), + To: common.ToHex(crypto.FromECDSAPub(message.To)), + Sent: message.Sent.Unix(), + TTL: int64(message.TTL / time.Second), + Hash: common.ToHex(message.Hash.Bytes()), + } +} |