// Copyright 2018 The go-ethereum Authors
// This file is part of the go-ethereum library.
//
// The go-ethereum library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The go-ethereum library 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 Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
package pss
import (
"context"
"errors"
"fmt"
"github.com/tangerine-network/go-tangerine/common/hexutil"
"github.com/tangerine-network/go-tangerine/crypto"
"github.com/tangerine-network/go-tangerine/p2p"
"github.com/tangerine-network/go-tangerine/rpc"
"github.com/tangerine-network/go-tangerine/swarm/log"
)
// Wrapper for receiving pss messages when using the pss API
// providing access to sender of message
type APIMsg struct {
Msg hexutil.Bytes
Asymmetric bool
Key string
}
// Additional public methods accessible through API for pss
type API struct {
*Pss
}
func NewAPI(ps *Pss) *API {
return &API{Pss: ps}
}
// Creates a new subscription for the caller. Enables external handling of incoming messages.
//
// A new handler is registered in pss for the supplied topic
//
// All incoming messages to the node matching this topic will be encapsulated in the APIMsg
// struct and sent to the subscriber
func (pssapi *API) Receive(ctx context.Context, topic Topic, raw bool, prox bool) (*rpc.Subscription, error) {
notifier, supported := rpc.NotifierFromContext(ctx)
if !supported {
return nil, fmt.Errorf("Subscribe not supported")
}
psssub := notifier.CreateSubscription()
hndlr := NewHandler(func(msg []byte, p *p2p.Peer, asymmetric bool, keyid string) error {
apimsg := &APIMsg{
Msg: hexutil.Bytes(msg),
Asymmetric: asymmetric,
Key: keyid,
}
if err := notifier.Notify(psssub.ID, apimsg); err != nil {
log.Warn(fmt.Sprintf("notification on pss sub topic rpc (sub %v) msg %v failed!", psssub.ID, msg))
}
return nil
})
if raw {
hndlr.caps.raw = true
}
if prox {
hndlr.caps.prox = true
}
deregf := pssapi.Register(&topic, hndlr)
go func() {
defer deregf()
select {
case err := <-psssub.Err():
log.Warn(fmt.Sprintf("caught subscription error in pss sub topic %x: %v", topic, err))
case <-notifier.Closed():
log.Warn(fmt.Sprintf("rpc sub notifier closed"))
}
}()
return psssub, nil
}
func (pssapi *API) GetAddress(topic Topic, asymmetric bool, key string) (PssAddress, error) {
var addr PssAddress
if asymmetric {
peer, ok := pssapi.Pss.pubKeyPool[key][topic]
if !ok {
return nil, fmt.Errorf("pubkey/topic pair %x/%x doesn't exist", key, topic)
}
addr = peer.address
} else {
peer, ok := pssapi.Pss.symKeyPool[key][topic]
if !ok {
return nil, fmt.Errorf("symkey/topic pair %x/%x doesn't exist", key, topic)
}
addr = peer.address
}
return addr, nil
}
// Retrieves the node's base address in hex form
func (pssapi *API) BaseAddr() (PssAddress, error) {
return PssAddress(pssapi.Pss.BaseAddr()), nil
}
// Retrieves the node's public key in hex form
func (pssapi *API) GetPublicKey() (keybytes hexutil.Bytes) {
key := pssapi.Pss.PublicKey()
keybytes = crypto.FromECDSAPub(key)
return keybytes
}
// Set Public key to associate with a particular Pss peer
func (pssapi *API) SetPeerPublicKey(pubkey hexutil.Bytes, topic Topic, addr PssAddress) error {
pk, err := crypto.UnmarshalPubkey(pubkey)
if err != nil {
return fmt.Errorf("Cannot unmarshal pubkey: %x", pubkey)
}
err = pssapi.Pss.SetPeerPublicKey(pk, topic, addr)
if err != nil {
return fmt.Errorf("Invalid key: %x", pk)
}
return nil
}
func (pssapi *API) GetSymmetricKey(symkeyid string) (hexutil.Bytes, error) {
symkey, err := pssapi.Pss.GetSymmetricKey(symkeyid)
return hexutil.Bytes(symkey), err
}
func (pssapi *API) GetSymmetricAddressHint(topic Topic, symkeyid string) (PssAddress, error) {
return pssapi.Pss.symKeyPool[symkeyid][topic].address, nil
}
func (pssapi *API) GetAsymmetricAddressHint(topic Topic, pubkeyid string) (PssAddress, error) {
return pssapi.Pss.pubKeyPool[pubkeyid][topic].address, nil
}
func (pssapi *API) StringToTopic(topicstring string) (Topic, error) {
topicbytes := BytesToTopic([]byte(topicstring))
if topicbytes == rawTopic {
return rawTopic, errors.New("Topic string hashes to 0x00000000 and cannot be used")
}
return topicbytes, nil
}
func (pssapi *API) SendAsym(pubkeyhex string, topic Topic, msg hexutil.Bytes) error {
if err := validateMsg(msg); err != nil {
return err
}
return pssapi.Pss.SendAsym(pubkeyhex, topic, msg[:])
}
func (pssapi *API) SendSym(symkeyhex string, topic Topic, msg hexutil.Bytes) error {
if err := validateMsg(msg); err != nil {
return err
}
return pssapi.Pss.SendSym(symkeyhex, topic, msg[:])
}
func (pssapi *API) SendRaw(addr hexutil.Bytes, topic Topic, msg hexutil.Bytes) error {
if err := validateMsg(msg); err != nil {
return err
}
return pssapi.Pss.SendRaw(PssAddress(addr), topic, msg[:])
}
func (pssapi *API) GetPeerTopics(pubkeyhex string) ([]Topic, error) {
topics, _, err := pssapi.Pss.GetPublickeyPeers(pubkeyhex)
return topics, err
}
func (pssapi *API) GetPeerAddress(pubkeyhex string, topic Topic) (PssAddress, error) {
return pssapi.Pss.getPeerAddress(pubkeyhex, topic)
}
func validateMsg(msg []byte) error {
if len(msg) == 0 {
return errors.New("invalid message length")
}
return nil
}
