forked from cerc-io/plugeth
282 lines
9.6 KiB
Go
282 lines
9.6 KiB
Go
|
// Copyright 2019 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 (
|
||
|
"crypto/ecdsa"
|
||
|
"errors"
|
||
|
"fmt"
|
||
|
"sync"
|
||
|
|
||
|
"github.com/ethereum/go-ethereum/common"
|
||
|
"github.com/ethereum/go-ethereum/crypto"
|
||
|
"github.com/ethereum/go-ethereum/metrics"
|
||
|
"github.com/ethereum/go-ethereum/swarm/log"
|
||
|
whisper "github.com/ethereum/go-ethereum/whisper/whisperv6"
|
||
|
)
|
||
|
|
||
|
type KeyStore struct {
|
||
|
w *whisper.Whisper // key and encryption backend
|
||
|
|
||
|
mx sync.RWMutex
|
||
|
pubKeyPool map[string]map[Topic]*pssPeer // mapping of hex public keys to peer address by topic.
|
||
|
symKeyPool map[string]map[Topic]*pssPeer // mapping of symkeyids to peer address by topic.
|
||
|
symKeyDecryptCache []*string // fast lookup of symkeys recently used for decryption; last used is on top of stack
|
||
|
symKeyDecryptCacheCursor int // modular cursor pointing to last used, wraps on symKeyDecryptCache array
|
||
|
}
|
||
|
|
||
|
func loadKeyStore() *KeyStore {
|
||
|
return &KeyStore{
|
||
|
w: whisper.New(&whisper.DefaultConfig),
|
||
|
|
||
|
pubKeyPool: make(map[string]map[Topic]*pssPeer),
|
||
|
symKeyPool: make(map[string]map[Topic]*pssPeer),
|
||
|
symKeyDecryptCache: make([]*string, defaultSymKeyCacheCapacity),
|
||
|
}
|
||
|
}
|
||
|
|
||
|
func (ks *KeyStore) isSymKeyStored(key string) bool {
|
||
|
ks.mx.RLock()
|
||
|
defer ks.mx.RUnlock()
|
||
|
var ok bool
|
||
|
_, ok = ks.symKeyPool[key]
|
||
|
return ok
|
||
|
}
|
||
|
|
||
|
func (ks *KeyStore) isPubKeyStored(key string) bool {
|
||
|
ks.mx.RLock()
|
||
|
defer ks.mx.RUnlock()
|
||
|
var ok bool
|
||
|
_, ok = ks.pubKeyPool[key]
|
||
|
return ok
|
||
|
}
|
||
|
|
||
|
func (ks *KeyStore) getPeerSym(symkeyid string, topic Topic) (*pssPeer, bool) {
|
||
|
ks.mx.RLock()
|
||
|
defer ks.mx.RUnlock()
|
||
|
psp, ok := ks.symKeyPool[symkeyid][topic]
|
||
|
return psp, ok
|
||
|
}
|
||
|
|
||
|
func (ks *KeyStore) getPeerPub(pubkeyid string, topic Topic) (*pssPeer, bool) {
|
||
|
ks.mx.RLock()
|
||
|
defer ks.mx.RUnlock()
|
||
|
psp, ok := ks.pubKeyPool[pubkeyid][topic]
|
||
|
return psp, ok
|
||
|
}
|
||
|
|
||
|
// Links a peer ECDSA public key to a topic.
|
||
|
// This is required for asymmetric message exchange on the given topic.
|
||
|
// The value in `address` will be used as a routing hint for the public key / topic association.
|
||
|
func (ks *KeyStore) SetPeerPublicKey(pubkey *ecdsa.PublicKey, topic Topic, address PssAddress) error {
|
||
|
if err := validateAddress(address); err != nil {
|
||
|
return err
|
||
|
}
|
||
|
pubkeybytes := crypto.FromECDSAPub(pubkey)
|
||
|
if len(pubkeybytes) == 0 {
|
||
|
return fmt.Errorf("invalid public key: %v", pubkey)
|
||
|
}
|
||
|
pubkeyid := common.ToHex(pubkeybytes)
|
||
|
psp := &pssPeer{
|
||
|
address: address,
|
||
|
}
|
||
|
ks.mx.Lock()
|
||
|
if _, ok := ks.pubKeyPool[pubkeyid]; !ok {
|
||
|
ks.pubKeyPool[pubkeyid] = make(map[Topic]*pssPeer)
|
||
|
}
|
||
|
ks.pubKeyPool[pubkeyid][topic] = psp
|
||
|
ks.mx.Unlock()
|
||
|
log.Trace("added pubkey", "pubkeyid", pubkeyid, "topic", topic, "address", address)
|
||
|
return nil
|
||
|
}
|
||
|
|
||
|
// adds a symmetric key to the pss key pool, and optionally adds the key to the
|
||
|
// collection of keys used to attempt symmetric decryption of incoming messages
|
||
|
func (ks *KeyStore) addSymmetricKeyToPool(keyid string, topic Topic, address PssAddress, addtocache bool, protected bool) {
|
||
|
psp := &pssPeer{
|
||
|
address: address,
|
||
|
protected: protected,
|
||
|
}
|
||
|
ks.mx.Lock()
|
||
|
if _, ok := ks.symKeyPool[keyid]; !ok {
|
||
|
ks.symKeyPool[keyid] = make(map[Topic]*pssPeer)
|
||
|
}
|
||
|
ks.symKeyPool[keyid][topic] = psp
|
||
|
ks.mx.Unlock()
|
||
|
if addtocache {
|
||
|
ks.symKeyDecryptCacheCursor++
|
||
|
ks.symKeyDecryptCache[ks.symKeyDecryptCacheCursor%cap(ks.symKeyDecryptCache)] = &keyid
|
||
|
}
|
||
|
}
|
||
|
|
||
|
// Returns all recorded topic and address combination for a specific public key
|
||
|
func (ks *KeyStore) GetPublickeyPeers(keyid string) (topic []Topic, address []PssAddress, err error) {
|
||
|
ks.mx.RLock()
|
||
|
defer ks.mx.RUnlock()
|
||
|
for t, peer := range ks.pubKeyPool[keyid] {
|
||
|
topic = append(topic, t)
|
||
|
address = append(address, peer.address)
|
||
|
}
|
||
|
return topic, address, nil
|
||
|
}
|
||
|
|
||
|
func (ks *KeyStore) getPeerAddress(keyid string, topic Topic) (PssAddress, error) {
|
||
|
ks.mx.RLock()
|
||
|
defer ks.mx.RUnlock()
|
||
|
if peers, ok := ks.pubKeyPool[keyid]; ok {
|
||
|
if t, ok := peers[topic]; ok {
|
||
|
return t.address, nil
|
||
|
}
|
||
|
}
|
||
|
return nil, fmt.Errorf("peer with pubkey %s, topic %x not found", keyid, topic)
|
||
|
}
|
||
|
|
||
|
// Attempt to decrypt, validate and unpack a symmetrically encrypted message.
|
||
|
// If successful, returns the unpacked whisper ReceivedMessage struct
|
||
|
// encapsulating the decrypted message, and the whisper backend id
|
||
|
// of the symmetric key used to decrypt the message.
|
||
|
// It fails if decryption of the message fails or if the message is corrupted.
|
||
|
func (ks *KeyStore) processSym(envelope *whisper.Envelope) (*whisper.ReceivedMessage, string, PssAddress, error) {
|
||
|
metrics.GetOrRegisterCounter("pss.process.sym", nil).Inc(1)
|
||
|
|
||
|
for i := ks.symKeyDecryptCacheCursor; i > ks.symKeyDecryptCacheCursor-cap(ks.symKeyDecryptCache) && i > 0; i-- {
|
||
|
symkeyid := ks.symKeyDecryptCache[i%cap(ks.symKeyDecryptCache)]
|
||
|
symkey, err := ks.w.GetSymKey(*symkeyid)
|
||
|
if err != nil {
|
||
|
continue
|
||
|
}
|
||
|
recvmsg, err := envelope.OpenSymmetric(symkey)
|
||
|
if err != nil {
|
||
|
continue
|
||
|
}
|
||
|
if !recvmsg.ValidateAndParse() {
|
||
|
return nil, "", nil, errors.New("symmetrically encrypted message has invalid signature or is corrupt")
|
||
|
}
|
||
|
var from PssAddress
|
||
|
ks.mx.RLock()
|
||
|
if ks.symKeyPool[*symkeyid][Topic(envelope.Topic)] != nil {
|
||
|
from = ks.symKeyPool[*symkeyid][Topic(envelope.Topic)].address
|
||
|
}
|
||
|
ks.mx.RUnlock()
|
||
|
ks.symKeyDecryptCacheCursor++
|
||
|
ks.symKeyDecryptCache[ks.symKeyDecryptCacheCursor%cap(ks.symKeyDecryptCache)] = symkeyid
|
||
|
return recvmsg, *symkeyid, from, nil
|
||
|
}
|
||
|
return nil, "", nil, errors.New("could not decrypt message")
|
||
|
}
|
||
|
|
||
|
// Attempt to decrypt, validate and unpack an asymmetrically encrypted message.
|
||
|
// If successful, returns the unpacked whisper ReceivedMessage struct
|
||
|
// encapsulating the decrypted message, and the byte representation of
|
||
|
// the public key used to decrypt the message.
|
||
|
// It fails if decryption of message fails, or if the message is corrupted.
|
||
|
func (ks *Pss) processAsym(envelope *whisper.Envelope) (*whisper.ReceivedMessage, string, PssAddress, error) {
|
||
|
metrics.GetOrRegisterCounter("pss.process.asym", nil).Inc(1)
|
||
|
|
||
|
recvmsg, err := envelope.OpenAsymmetric(ks.privateKey)
|
||
|
if err != nil {
|
||
|
return nil, "", nil, fmt.Errorf("could not decrypt message: %s", err)
|
||
|
}
|
||
|
// check signature (if signed), strip padding
|
||
|
if !recvmsg.ValidateAndParse() {
|
||
|
return nil, "", nil, errors.New("invalid message")
|
||
|
}
|
||
|
pubkeyid := common.ToHex(crypto.FromECDSAPub(recvmsg.Src))
|
||
|
var from PssAddress
|
||
|
ks.mx.RLock()
|
||
|
if ks.pubKeyPool[pubkeyid][Topic(envelope.Topic)] != nil {
|
||
|
from = ks.pubKeyPool[pubkeyid][Topic(envelope.Topic)].address
|
||
|
}
|
||
|
ks.mx.RUnlock()
|
||
|
return recvmsg, pubkeyid, from, nil
|
||
|
}
|
||
|
|
||
|
// Symkey garbage collection
|
||
|
// a key is removed if:
|
||
|
// - it is not marked as protected
|
||
|
// - it is not in the incoming decryption cache
|
||
|
func (ks *Pss) cleanKeys() (count int) {
|
||
|
for keyid, peertopics := range ks.symKeyPool {
|
||
|
var expiredtopics []Topic
|
||
|
for topic, psp := range peertopics {
|
||
|
if psp.protected {
|
||
|
continue
|
||
|
}
|
||
|
|
||
|
var match bool
|
||
|
for i := ks.symKeyDecryptCacheCursor; i > ks.symKeyDecryptCacheCursor-cap(ks.symKeyDecryptCache) && i > 0; i-- {
|
||
|
cacheid := ks.symKeyDecryptCache[i%cap(ks.symKeyDecryptCache)]
|
||
|
if *cacheid == keyid {
|
||
|
match = true
|
||
|
}
|
||
|
}
|
||
|
if !match {
|
||
|
expiredtopics = append(expiredtopics, topic)
|
||
|
}
|
||
|
}
|
||
|
for _, topic := range expiredtopics {
|
||
|
ks.mx.Lock()
|
||
|
delete(ks.symKeyPool[keyid], topic)
|
||
|
log.Trace("symkey cleanup deletion", "symkeyid", keyid, "topic", topic, "val", ks.symKeyPool[keyid])
|
||
|
ks.mx.Unlock()
|
||
|
count++
|
||
|
}
|
||
|
}
|
||
|
return count
|
||
|
}
|
||
|
|
||
|
// Automatically generate a new symkey for a topic and address hint
|
||
|
func (ks *KeyStore) GenerateSymmetricKey(topic Topic, address PssAddress, addToCache bool) (string, error) {
|
||
|
keyid, err := ks.w.GenerateSymKey()
|
||
|
if err == nil {
|
||
|
ks.addSymmetricKeyToPool(keyid, topic, address, addToCache, false)
|
||
|
}
|
||
|
return keyid, err
|
||
|
}
|
||
|
|
||
|
// Returns a symmetric key byte sequence stored in the whisper backend by its unique id.
|
||
|
// Passes on the error value from the whisper backend.
|
||
|
func (ks *KeyStore) GetSymmetricKey(symkeyid string) ([]byte, error) {
|
||
|
return ks.w.GetSymKey(symkeyid)
|
||
|
}
|
||
|
|
||
|
// Links a peer symmetric key (arbitrary byte sequence) to a topic.
|
||
|
//
|
||
|
// This is required for symmetrically encrypted message exchange on the given topic.
|
||
|
//
|
||
|
// The key is stored in the whisper backend.
|
||
|
//
|
||
|
// If addtocache is set to true, the key will be added to the cache of keys
|
||
|
// used to attempt symmetric decryption of incoming messages.
|
||
|
//
|
||
|
// Returns a string id that can be used to retrieve the key bytes
|
||
|
// from the whisper backend (see pss.GetSymmetricKey())
|
||
|
func (ks *KeyStore) SetSymmetricKey(key []byte, topic Topic, address PssAddress, addtocache bool) (string, error) {
|
||
|
if err := validateAddress(address); err != nil {
|
||
|
return "", err
|
||
|
}
|
||
|
return ks.setSymmetricKey(key, topic, address, addtocache, true)
|
||
|
}
|
||
|
|
||
|
func (ks *KeyStore) setSymmetricKey(key []byte, topic Topic, address PssAddress, addtocache bool, protected bool) (string, error) {
|
||
|
keyid, err := ks.w.AddSymKeyDirect(key)
|
||
|
if err == nil {
|
||
|
ks.addSymmetricKeyToPool(keyid, topic, address, addtocache, protected)
|
||
|
}
|
||
|
return keyid, err
|
||
|
}
|