// Copyright 2016 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 light
import (
"bytes"
"context"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/core"
"github.com/ethereum/go-ethereum/core/types"
"github.com/ethereum/go-ethereum/crypto"
"github.com/ethereum/go-ethereum/rlp"
)
var sha3_nil = crypto.Keccak256Hash(nil)
func GetHeaderByNumber(ctx context.Context, odr OdrBackend, number uint64) (*types.Header, error) {
db := odr.Database()
hash := core.GetCanonicalHash(db, number)
if (hash != common.Hash{}) {
// if there is a canonical hash, there is a header too
header := core.GetHeader(db, hash, number)
if header == nil {
panic("Canonical hash present but header not found")
}
return header, nil
}
var (
chtCount, sectionHeadNum uint64
sectionHead common.Hash
)
if odr.ChtIndexer() != nil {
chtCount, sectionHeadNum, sectionHead = odr.ChtIndexer().Sections()
canonicalHash := core.GetCanonicalHash(db, sectionHeadNum)
// if the CHT was injected as a trusted checkpoint, we have no canonical hash yet so we accept zero hash too
for chtCount > 0 && canonicalHash != sectionHead && canonicalHash != (common.Hash{}) {
chtCount--
if chtCount > 0 {
sectionHeadNum = chtCount*CHTFrequencyClient - 1
sectionHead = odr.ChtIndexer().SectionHead(chtCount - 1)
canonicalHash = core.GetCanonicalHash(db, sectionHeadNum)
}
}
}
if number >= chtCount*CHTFrequencyClient {
return nil, ErrNoTrustedCht
}
r := &ChtRequest{ChtRoot: GetChtRoot(db, chtCount-1, sectionHead), ChtNum: chtCount - 1, BlockNum: number}
if err := odr.Retrieve(ctx, r); err != nil {
return nil, err
}
return r.Header, nil
}
func GetCanonicalHash(ctx context.Context, odr OdrBackend, number uint64) (common.Hash, error) {
hash := core.GetCanonicalHash(odr.Database(), number)
if (hash != common.Hash{}) {
return hash, nil
}
header, err := GetHeaderByNumber(ctx, odr, number)
if header != nil {
return header.Hash(), nil
}
return common.Hash{}, err
}
// GetBodyRLP retrieves the block body (transactions and uncles) in RLP encoding.
func GetBodyRLP(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (rlp.RawValue, error) {
if data := core.GetBodyRLP(odr.Database(), hash, number); data != nil {
return data, nil
}
r := &BlockRequest{Hash: hash, Number: number}
if err := odr.Retrieve(ctx, r); err != nil {
return nil, err
} else {
return r.Rlp, nil
}
}
// GetBody retrieves the block body (transactons, uncles) corresponding to the
// hash.
func GetBody(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (*types.Body, error) {
data, err := GetBodyRLP(ctx, odr, hash, number)
if err != nil {
return nil, err
}
body := new(types.Body)
if err := rlp.Decode(bytes.NewReader(data), body); err != nil {
return nil, err
}
return body, nil
}
// GetBlock retrieves an entire block corresponding to the hash, assembling it
// back from the stored header and body.
func GetBlock(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (*types.Block, error) {
// Retrieve the block header and body contents
header := core.GetHeader(odr.Database(), hash, number)
if header == nil {
return nil, ErrNoHeader
}
body, err := GetBody(ctx, odr, hash, number)
if err != nil {
return nil, err
}
// Reassemble the block and return
return types.NewBlockWithHeader(header).WithBody(body.Transactions, body.Uncles), nil
}
// GetBlockReceipts retrieves the receipts generated by the transactions included
// in a block given by its hash.
func GetBlockReceipts(ctx context.Context, odr OdrBackend, hash common.Hash, number uint64) (types.Receipts, error) {
receipts := core.GetBlockReceipts(odr.Database(), hash, number)
if receipts != nil {
return receipts, nil
}
r := &ReceiptsRequest{Hash: hash, Number: number}
if err := odr.Retrieve(ctx, r); err != nil {
return nil, err
}
return r.Receipts, nil
}
// GetBloomBits retrieves a batch of compressed bloomBits vectors belonging to the given bit index and section indexes
func GetBloomBits(ctx context.Context, odr OdrBackend, bitIdx uint, sectionIdxList []uint64) ([][]byte, error) {
db := odr.Database()
result := make([][]byte, len(sectionIdxList))
var (
reqList []uint64
reqIdx []int
)
var (
bloomTrieCount, sectionHeadNum uint64
sectionHead common.Hash
)
if odr.BloomTrieIndexer() != nil {
bloomTrieCount, sectionHeadNum, sectionHead = odr.BloomTrieIndexer().Sections()
canonicalHash := core.GetCanonicalHash(db, sectionHeadNum)
// if the BloomTrie was injected as a trusted checkpoint, we have no canonical hash yet so we accept zero hash too
for bloomTrieCount > 0 && canonicalHash != sectionHead && canonicalHash != (common.Hash{}) {
bloomTrieCount--
if bloomTrieCount > 0 {
sectionHeadNum = bloomTrieCount*BloomTrieFrequency - 1
sectionHead = odr.BloomTrieIndexer().SectionHead(bloomTrieCount - 1)
canonicalHash = core.GetCanonicalHash(db, sectionHeadNum)
}
}
}
for i, sectionIdx := range sectionIdxList {
sectionHead := core.GetCanonicalHash(db, (sectionIdx+1)*BloomTrieFrequency-1)
// if we don't have the canonical hash stored for this section head number, we'll still look for
// an entry with a zero sectionHead (we store it with zero section head too if we don't know it
// at the time of the retrieval)
bloomBits, err := core.GetBloomBits(db, bitIdx, sectionIdx, sectionHead)
if err == nil {
result[i] = bloomBits
} else {
if sectionIdx >= bloomTrieCount {
return nil, ErrNoTrustedBloomTrie
}
reqList = append(reqList, sectionIdx)
reqIdx = append(reqIdx, i)
}
}
if reqList == nil {
return result, nil
}
r := &BloomRequest{BloomTrieRoot: GetBloomTrieRoot(db, bloomTrieCount-1, sectionHead), BloomTrieNum: bloomTrieCount - 1, BitIdx: bitIdx, SectionIdxList: reqList}
if err := odr.Retrieve(ctx, r); err != nil {
return nil, err
} else {
for i, idx := range reqIdx {
result[idx] = r.BloomBits[i]
}
return result, nil
}
}
