les, light: LES/2 protocol version (#14970)

This PR implements the new LES protocol version extensions:

* new and more efficient Merkle proofs reply format (when replying to
  a multiple Merkle proofs request, we just send a single set of trie
  nodes containing all necessary nodes)
* BBT (BloomBitsTrie) works similarly to the existing CHT and contains
  the bloombits search data to speed up log searches
* GetTxStatusMsg returns the inclusion position or the
  pending/queued/unknown state of a transaction referenced by hash
* an optional signature of new block data (number/hash/td) can be
  included in AnnounceMsg to provide an option for "very light
  clients" (mobile/embedded devices) to skip expensive Ethash check
  and accept multiple signatures of somewhat trusted servers (still a
  lot better than trusting a single server completely and retrieving
  everything through RPC). The new client mode is not implemented in
  this PR, just the protocol extension.

1 files changed, 24 insertions, 12 deletions

diff --git a/light/lightchain.go b/light/lightchain.go
index 4c877a771..30baeaccb 100644
--- a/light/lightchain.go
+++ b/light/lightchain.go
@@ -95,15 +95,8 @@ func NewLightChain(odr OdrBackend, config *params.ChainConfig, engine consensus.
 	if bc.genesisBlock == nil {
 		return nil, core.ErrNoGenesis
 	}
-	if bc.genesisBlock.Hash() == params.MainnetGenesisHash {
-		// add trusted CHT
-		WriteTrustedCht(bc.chainDb, TrustedCht{Number: 1040, Root: common.HexToHash("bb4fb4076cbe6923c8a8ce8f158452bbe19564959313466989fda095a60884ca")})
-		log.Info("Added trusted CHT for mainnet")
-	}
-	if bc.genesisBlock.Hash() == params.TestnetGenesisHash {
-		// add trusted CHT
-		WriteTrustedCht(bc.chainDb, TrustedCht{Number: 400, Root: common.HexToHash("2a4befa19e4675d939c3dc22dca8c6ae9fcd642be1f04b06bd6e4203cc304660")})
-		log.Info("Added trusted CHT for ropsten testnet")
+	if cp, ok := trustedCheckpoints[bc.genesisBlock.Hash()]; ok {
+		bc.addTrustedCheckpoint(cp)
 	}
 
 	if err := bc.loadLastState(); err != nil {
@@ -120,6 +113,22 @@ func NewLightChain(odr OdrBackend, config *params.ChainConfig, engine consensus.
 	return bc, nil
 }
 
+// addTrustedCheckpoint adds a trusted checkpoint to the blockchain
+func (self *LightChain) addTrustedCheckpoint(cp trustedCheckpoint) {
+	if self.odr.ChtIndexer() != nil {
+		StoreChtRoot(self.chainDb, cp.sectionIdx, cp.sectionHead, cp.chtRoot)
+		self.odr.ChtIndexer().AddKnownSectionHead(cp.sectionIdx, cp.sectionHead)
+	}
+	if self.odr.BloomTrieIndexer() != nil {
+		StoreBloomTrieRoot(self.chainDb, cp.sectionIdx, cp.sectionHead, cp.bloomTrieRoot)
+		self.odr.BloomTrieIndexer().AddKnownSectionHead(cp.sectionIdx, cp.sectionHead)
+	}
+	if self.odr.BloomIndexer() != nil {
+		self.odr.BloomIndexer().AddKnownSectionHead(cp.sectionIdx, cp.sectionHead)
+	}
+	log.Info("Added trusted checkpoint", "chain name", cp.name)
+}
+
 func (self *LightChain) getProcInterrupt() bool {
 	return atomic.LoadInt32(&self.procInterrupt) == 1
 }
@@ -449,10 +458,13 @@ func (self *LightChain) GetHeaderByNumberOdr(ctx context.Context, number uint64)
 }
 
 func (self *LightChain) SyncCht(ctx context.Context) bool {
+	if self.odr.ChtIndexer() == nil {
+		return false
+	}
 	headNum := self.CurrentHeader().Number.Uint64()
-	cht := GetTrustedCht(self.chainDb)
-	if headNum+1 < cht.Number*ChtFrequency {
-		num := cht.Number*ChtFrequency - 1
+	chtCount, _, _ := self.odr.ChtIndexer().Sections()
+	if headNum+1 < chtCount*ChtFrequency {
+		num := chtCount*ChtFrequency - 1
 		header, err := GetHeaderByNumber(ctx, self.odr, num)
 		if header != nil && err == nil {
 			self.mu.Lock()