lotus/chain/sync.go
2019-07-05 16:36:08 +02:00

696 lines
15 KiB
Go

package chain
import (
"context"
"fmt"
"sync"
"github.com/ipfs/go-cid"
dstore "github.com/ipfs/go-datastore"
"github.com/ipfs/go-hamt-ipld"
bstore "github.com/ipfs/go-ipfs-blockstore"
peer "github.com/libp2p/go-libp2p-peer"
"github.com/pkg/errors"
"github.com/whyrusleeping/sharray"
)
type Syncer struct {
// The heaviest known tipset in the network.
head *TipSet
// The interface for accessing and putting tipsets into local storage
store *ChainStore
// The known genesis tipset
genesis *TipSet
// the current mode the syncer is in
syncMode SyncMode
syncLock sync.Mutex
// TipSets known to be invalid
bad BadTipSetCache
// handle to the block sync service
bsync *BlockSync
// peer heads
// Note: clear cache on disconnects
peerHeads map[peer.ID]*TipSet
peerHeadsLk sync.Mutex
}
func NewSyncer(cs *ChainStore, bsync *BlockSync) (*Syncer, error) {
gen, err := cs.GetGenesis()
if err != nil {
return nil, err
}
gent, err := NewTipSet([]*BlockHeader{gen})
if err != nil {
return nil, err
}
return &Syncer{
syncMode: Bootstrap,
genesis: gent,
bsync: bsync,
peerHeads: make(map[peer.ID]*TipSet),
head: cs.GetHeaviestTipSet(),
store: cs,
}, nil
}
type SyncMode int
const (
Unknown = SyncMode(iota)
Bootstrap
CaughtUp
)
type BadTipSetCache struct {
badBlocks map[cid.Cid]struct{}
}
type BlockSet struct {
tset map[uint64]*TipSet
head *TipSet
}
func (bs *BlockSet) Insert(ts *TipSet) {
if bs.tset == nil {
bs.tset = make(map[uint64]*TipSet)
}
if bs.head == nil || ts.Height() > bs.head.Height() {
bs.head = ts
}
bs.tset[ts.Height()] = ts
}
func (bs *BlockSet) GetByHeight(h uint64) *TipSet {
return bs.tset[h]
}
func (bs *BlockSet) PersistTo(cs *ChainStore) error {
for _, ts := range bs.tset {
for _, b := range ts.Blocks() {
if err := cs.persistBlockHeader(b); err != nil {
return err
}
}
}
return nil
}
func (bs *BlockSet) Head() *TipSet {
return bs.head
}
const BootstrapPeerThreshold = 1
// InformNewHead informs the syncer about a new potential tipset
// This should be called when connecting to new peers, and additionally
// when receiving new blocks from the network
func (syncer *Syncer) InformNewHead(from peer.ID, fts *FullTipSet) {
if fts == nil {
panic("bad")
}
syncer.peerHeadsLk.Lock()
syncer.peerHeads[from] = fts.TipSet()
syncer.peerHeadsLk.Unlock()
syncer.bsync.AddPeer(from)
go func() {
syncer.syncLock.Lock()
defer syncer.syncLock.Unlock()
switch syncer.syncMode {
case Bootstrap:
syncer.SyncBootstrap()
case CaughtUp:
if err := syncer.SyncCaughtUp(fts); err != nil {
log.Errorf("sync error: %s", err)
}
case Unknown:
panic("invalid syncer state")
}
}()
}
func (syncer *Syncer) GetPeers() []peer.ID {
syncer.peerHeadsLk.Lock()
defer syncer.peerHeadsLk.Unlock()
var out []peer.ID
for p, _ := range syncer.peerHeads {
out = append(out, p)
}
return out
}
func (syncer *Syncer) InformNewBlock(from peer.ID, blk *FullBlock) {
// TODO: search for other blocks that could form a tipset with this block
// and then send that tipset to InformNewHead
fts := &FullTipSet{Blocks: []*FullBlock{blk}}
syncer.InformNewHead(from, fts)
}
// SyncBootstrap is used to synchronise your chain when first joining
// the network, or when rejoining after significant downtime.
func (syncer *Syncer) SyncBootstrap() {
fmt.Println("Sync bootstrap!")
defer fmt.Println("bye bye sync bootstrap")
ctx := context.Background()
if syncer.syncMode == CaughtUp {
log.Errorf("Called SyncBootstrap while in caught up mode")
return
}
selectedHead, err := syncer.selectHead(syncer.peerHeads)
if err != nil {
log.Error("failed to select head: ", err)
return
}
blockSet := []*TipSet{selectedHead}
cur := selectedHead.Cids()
for /* would be cool to have a terminating condition maybe */ {
// NB: GetBlocks validates that the blocks are in-fact the ones we
// requested, and that they are correctly linked to eachother. It does
// not validate any state transitions
fmt.Println("Get blocks: ", cur)
blks, err := syncer.bsync.GetBlocks(context.TODO(), cur, 10)
if err != nil {
log.Error("failed to get blocks: ", err)
return
}
for _, b := range blks {
blockSet = append(blockSet, b)
}
if blks[len(blks)-1].Height() == 0 {
break
}
cur = blks[len(blks)-1].Parents()
}
// hacks. in the case that we request X blocks starting at height X+1, we
// won't get the genesis block in the returned blockset. This hacks around it
if blockSet[len(blockSet)-1].Height() != 0 {
blockSet = append(blockSet, syncer.genesis)
}
blockSet = reverse(blockSet)
genesis := blockSet[0]
if !genesis.Equals(syncer.genesis) {
// TODO: handle this...
log.Errorf("We synced to the wrong chain! %s != %s", genesis, syncer.genesis)
return
}
for _, ts := range blockSet {
for _, b := range ts.Blocks() {
if err := syncer.store.persistBlockHeader(b); err != nil {
log.Errorf("failed to persist synced blocks to the chainstore: %s", err)
return
}
}
}
// Fetch all the messages for all the blocks in this chain
windowSize := uint64(10)
for i := uint64(0); i <= selectedHead.Height(); i += windowSize {
bs := bstore.NewBlockstore(dstore.NewMapDatastore())
cst := hamt.CSTFromBstore(bs)
nextHeight := i + windowSize - 1
if nextHeight > selectedHead.Height() {
nextHeight = selectedHead.Height()
}
next := blockSet[nextHeight]
bstips, err := syncer.bsync.GetChainMessages(ctx, next, (nextHeight+1)-i)
if err != nil {
log.Errorf("failed to fetch messages: %s", err)
return
}
for bsi := 0; bsi < len(bstips); bsi++ {
cur := blockSet[i+uint64(bsi)]
bstip := bstips[len(bstips)-(bsi+1)]
fmt.Println("that loop: ", bsi, len(bstips))
fts, err := zipTipSetAndMessages(cst, cur, bstip.Messages, bstip.MsgIncludes)
if err != nil {
log.Error("zipping failed: ", err, bsi, i)
log.Error("height: ", selectedHead.Height())
log.Error("bstips: ", bstips)
log.Error("next height: ", nextHeight)
return
}
if err := syncer.ValidateTipSet(fts); err != nil {
log.Errorf("failed to validate tipset: %s", err)
return
}
}
for _, bst := range bstips {
for _, m := range bst.Messages {
if _, err := cst.Put(context.TODO(), m); err != nil {
log.Error("failed to persist messages: ", err)
return
}
}
}
if err := copyBlockstore(bs, syncer.store.bs); err != nil {
log.Errorf("failed to persist temp blocks: %s", err)
return
}
}
head := blockSet[len(blockSet)-1]
log.Errorf("Finished syncing! new head: %s", head.Cids())
syncer.store.maybeTakeHeavierTipSet(selectedHead)
syncer.head = head
syncer.syncMode = CaughtUp
}
func reverse(tips []*TipSet) []*TipSet {
out := make([]*TipSet, len(tips))
for i := 0; i < len(tips); i++ {
out[i] = tips[len(tips)-(i+1)]
}
return out
}
func copyBlockstore(from, to bstore.Blockstore) error {
cids, err := from.AllKeysChan(context.TODO())
if err != nil {
return err
}
for c := range cids {
b, err := from.Get(c)
if err != nil {
return err
}
if err := to.Put(b); err != nil {
return err
}
}
return nil
}
func zipTipSetAndMessages(cst *hamt.CborIpldStore, ts *TipSet, messages []*SignedMessage, msgincl [][]int) (*FullTipSet, error) {
if len(ts.Blocks()) != len(msgincl) {
return nil, fmt.Errorf("msgincl length didnt match tipset size")
}
fmt.Println("zipping messages: ", msgincl)
fmt.Println("into block: ", ts.Blocks()[0].Height)
fts := &FullTipSet{}
for bi, b := range ts.Blocks() {
var msgs []*SignedMessage
var msgCids []interface{}
for _, m := range msgincl[bi] {
msgs = append(msgs, messages[m])
msgCids = append(msgCids, messages[m].Cid())
}
mroot, err := sharray.Build(context.TODO(), 4, msgCids, cst)
if err != nil {
return nil, err
}
fmt.Println("messages: ", msgCids)
fmt.Println("message root: ", b.Messages, mroot)
if b.Messages != mroot {
return nil, fmt.Errorf("messages didnt match message root in header")
}
fb := &FullBlock{
Header: b,
Messages: msgs,
}
fts.Blocks = append(fts.Blocks, fb)
}
return fts, nil
}
func (syncer *Syncer) selectHead(heads map[peer.ID]*TipSet) (*TipSet, error) {
var headsArr []*TipSet
for _, ts := range heads {
headsArr = append(headsArr, ts)
}
sel := headsArr[0]
for i := 1; i < len(headsArr); i++ {
cur := headsArr[i]
yes, err := syncer.store.IsAncestorOf(cur, sel)
if err != nil {
return nil, err
}
if yes {
continue
}
yes, err = syncer.store.IsAncestorOf(sel, cur)
if err != nil {
return nil, err
}
if yes {
sel = cur
continue
}
nca, err := syncer.store.NearestCommonAncestor(cur, sel)
if err != nil {
return nil, err
}
if sel.Height()-nca.Height() > ForkLengthThreshold {
// TODO: handle this better than refusing to sync
return nil, fmt.Errorf("Conflict exists in heads set")
}
if syncer.store.Weight(cur) > syncer.store.Weight(sel) {
sel = cur
}
}
return sel, nil
}
func (syncer *Syncer) FetchTipSet(ctx context.Context, p peer.ID, cids []cid.Cid) (*FullTipSet, error) {
if fts, err := syncer.tryLoadFullTipSet(cids); err == nil {
return fts, nil
}
return syncer.bsync.GetFullTipSet(ctx, p, cids)
}
func (syncer *Syncer) tryLoadFullTipSet(cids []cid.Cid) (*FullTipSet, error) {
ts, err := syncer.store.LoadTipSet(cids)
if err != nil {
return nil, err
}
fts := &FullTipSet{}
for _, b := range ts.Blocks() {
messages, err := syncer.store.MessagesForBlock(b)
if err != nil {
return nil, err
}
fb := &FullBlock{
Header: b,
Messages: messages,
}
fts.Blocks = append(fts.Blocks, fb)
}
return fts, nil
}
// FullTipSet is an expanded version of the TipSet that contains all the blocks and messages
type FullTipSet struct {
Blocks []*FullBlock
tipset *TipSet
cids []cid.Cid
}
func NewFullTipSet(blks []*FullBlock) *FullTipSet {
return &FullTipSet{
Blocks: blks,
}
}
func (fts *FullTipSet) Cids() []cid.Cid {
if fts.cids != nil {
return fts.cids
}
var cids []cid.Cid
for _, b := range fts.Blocks {
cids = append(cids, b.Cid())
}
fts.cids = cids
return cids
}
func (fts *FullTipSet) TipSet() *TipSet {
if fts.tipset != nil {
return fts.tipset
}
var headers []*BlockHeader
for _, b := range fts.Blocks {
headers = append(headers, b.Header)
}
ts, err := NewTipSet(headers)
if err != nil {
panic(err)
}
return ts
}
// SyncCaughtUp is used to stay in sync once caught up to
// the rest of the network.
func (syncer *Syncer) SyncCaughtUp(maybeHead *FullTipSet) error {
ts := maybeHead.TipSet()
if syncer.genesis.Equals(ts) {
return nil
}
chain, err := syncer.collectChainCaughtUp(maybeHead)
if err != nil {
return err
}
for i := len(chain) - 1; i >= 0; i-- {
ts := chain[i]
if err := syncer.ValidateTipSet(ts); err != nil {
return errors.Wrap(err, "validate tipset failed")
}
syncer.store.PutTipSet(ts)
}
if err := syncer.store.PutTipSet(maybeHead); err != nil {
return errors.Wrap(err, "failed to put synced tipset to chainstore")
}
if syncer.store.Weight(chain[0].TipSet()) > syncer.store.Weight(syncer.head) {
fmt.Println("Accepted new head: ", chain[0].Cids())
syncer.head = chain[0].TipSet()
}
return nil
}
func (syncer *Syncer) ValidateTipSet(fts *FullTipSet) error {
ts := fts.TipSet()
if ts.Equals(syncer.genesis) {
return nil
}
for _, b := range fts.Blocks {
if err := syncer.ValidateBlock(b); err != nil {
return err
}
}
return nil
}
func (syncer *Syncer) ValidateBlock(b *FullBlock) error {
h := b.Header
stateroot, err := syncer.store.TipSetState(h.Parents)
if err != nil {
log.Error("get tipsetstate failed: ", h.Height, h.Parents, err)
return err
}
baseTs, err := syncer.store.LoadTipSet(b.Header.Parents)
if err != nil {
return err
}
vm, err := NewVM(stateroot, b.Header.Height, b.Header.Miner, syncer.store)
if err != nil {
return err
}
if err := vm.TransferFunds(NetworkAddress, b.Header.Miner, miningRewardForBlock(baseTs)); err != nil {
return err
}
var receipts []interface{}
for _, m := range b.Messages {
receipt, err := vm.ApplyMessage(&m.Message)
if err != nil {
return err
}
receipts = append(receipts, receipt)
}
cst := hamt.CSTFromBstore(syncer.store.bs)
recptRoot, err := sharray.Build(context.TODO(), 4, receipts, cst)
if err != nil {
return err
}
if recptRoot != b.Header.MessageReceipts {
return fmt.Errorf("receipts mismatched")
}
final, err := vm.Flush(context.TODO())
if err != nil {
return err
}
if b.Header.StateRoot != final {
return fmt.Errorf("final state root does not match block")
}
return nil
}
func DeductFunds(act *Actor, amt BigInt) error {
if BigCmp(act.Balance, amt) < 0 {
return fmt.Errorf("not enough funds")
}
act.Balance = BigSub(act.Balance, amt)
return nil
}
func DepositFunds(act *Actor, amt BigInt) {
act.Balance = BigAdd(act.Balance, amt)
}
func TryCreateAccountActor(st *StateTree, addr address.Address) (*Actor, error) {
act, err := makeActor(st, addr)
if err != nil {
return nil, err
}
_, err = st.RegisterNewAddress(addr, act)
if err != nil {
return nil, err
}
return act, nil
}
func makeActor(st *StateTree, addr address.Address) (*Actor, error) {
switch addr.Protocol() {
case address.BLS:
return NewBLSAccountActor(st, addr)
case address.SECP256K1:
return NewSecp256k1AccountActor(st, addr)
case address.ID:
return nil, fmt.Errorf("no actor with given ID")
case address.Actor:
return nil, fmt.Errorf("no such actor")
default:
return nil, fmt.Errorf("address has unsupported protocol: %d", addr.Protocol())
}
}
func NewBLSAccountActor(st *StateTree, addr address.Address) (*Actor, error) {
var acstate AccountActorState
acstate.Address = addr
c, err := st.store.Put(context.TODO(), acstate)
if err != nil {
return nil, err
}
nact := &Actor{
Code: AccountActorCodeCid,
Balance: NewInt(0),
Head: c,
}
return nact, nil
}
func NewSecp256k1AccountActor(st *StateTree, addr address.Address) (*Actor, error) {
nact := &Actor{
Code: AccountActorCodeCid,
Balance: NewInt(0),
Head: EmptyObjectCid,
}
return nact, nil
}
func (syncer *Syncer) Punctual(ts *TipSet) bool {
return true
}
func (syncer *Syncer) collectChainCaughtUp(fts *FullTipSet) ([]*FullTipSet, error) {
// fetch tipset and messages via bitswap
chain := []*FullTipSet{fts}
cur := fts.TipSet()
for {
ts, err := syncer.store.LoadTipSet(cur.Parents())
if err != nil {
panic("should do something better, like fetch? or error?")
}
return chain, nil // return the chain because we have this last block in our cache already.
if ts.Equals(syncer.genesis) {
break
}
/*
if !syncer.Punctual(ts) {
syncer.bad.InvalidateChain(chain)
syncer.bad.InvalidateTipSet(ts)
return nil, errors.New("tipset forks too far back from head")
}
*/
chain = append(chain, fts)
log.Error("received unknown chain in caught up mode...")
panic("for now, we panic...")
has, err := syncer.store.Contains(ts)
if err != nil {
return nil, err
}
if has {
// Store has record of this tipset.
return chain, nil
}
/*
parent, err := syncer.FetchTipSet(context.TODO(), ts.Parents())
if err != nil {
return nil, err
}
ts = parent
*/
}
return chain, nil
}