1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
// Copyright 2015 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 implements on-demand retrieval capable state and chain objects
// for the Ethereum Light Client.
package light
import (
"context"
"math/big"
"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/ethdb"
"github.com/ethereum/go-ethereum/rlp"
)
// NoOdr is the default context passed to an ODR capable function when the ODR
// service is not required.
var NoOdr = context.Background()
// OdrBackend is an interface to a backend service that handles ODR retrievals
type OdrBackend interface {
Database() ethdb.Database
Retrieve(ctx context.Context, req OdrRequest) error
}
// OdrRequest is an interface for retrieval requests
type OdrRequest interface {
StoreResult(db ethdb.Database)
}
// TrieID identifies a state or account storage trie
type TrieID struct {
BlockHash, Root common.Hash
BlockNumber uint64
AccKey []byte
}
// StateTrieID returns a TrieID for a state trie belonging to a certain block
// header.
func StateTrieID(header *types.Header) *TrieID {
return &TrieID{
BlockHash: header.Hash(),
BlockNumber: header.Number.Uint64(),
AccKey: nil,
Root: header.Root,
}
}
// StorageTrieID returns a TrieID for a contract storage trie at a given account
// of a given state trie. It also requires the root hash of the trie for
// checking Merkle proofs.
func StorageTrieID(state *TrieID, addr common.Address, root common.Hash) *TrieID {
return &TrieID{
BlockHash: state.BlockHash,
BlockNumber: state.BlockNumber,
AccKey: crypto.Keccak256(addr[:]),
Root: root,
}
}
// TrieRequest is the ODR request type for state/storage trie entries
type TrieRequest struct {
OdrRequest
Id *TrieID
Key []byte
Proof []rlp.RawValue
}
// StoreResult stores the retrieved data in local database
func (req *TrieRequest) StoreResult(db ethdb.Database) {
storeProof(db, req.Proof)
}
// storeProof stores the new trie nodes obtained from a merkle proof in the database
func storeProof(db ethdb.Database, proof []rlp.RawValue) {
for _, buf := range proof {
hash := crypto.Keccak256(buf)
val, _ := db.Get(hash)
if val == nil {
db.Put(hash, buf)
}
}
}
// CodeRequest is the ODR request type for retrieving contract code
type CodeRequest struct {
OdrRequest
Id *TrieID
Hash common.Hash
Data []byte
}
// StoreResult stores the retrieved data in local database
func (req *CodeRequest) StoreResult(db ethdb.Database) {
db.Put(req.Hash[:], req.Data)
}
// BlockRequest is the ODR request type for retrieving block bodies
type BlockRequest struct {
OdrRequest
Hash common.Hash
Number uint64
Rlp []byte
}
// StoreResult stores the retrieved data in local database
func (req *BlockRequest) StoreResult(db ethdb.Database) {
core.WriteBodyRLP(db, req.Hash, req.Number, req.Rlp)
}
// ReceiptsRequest is the ODR request type for retrieving block bodies
type ReceiptsRequest struct {
OdrRequest
Hash common.Hash
Number uint64
Receipts types.Receipts
}
// StoreResult stores the retrieved data in local database
func (req *ReceiptsRequest) StoreResult(db ethdb.Database) {
core.WriteBlockReceipts(db, req.Hash, req.Number, req.Receipts)
}
// TrieRequest is the ODR request type for state/storage trie entries
type ChtRequest struct {
OdrRequest
ChtNum, BlockNum uint64
ChtRoot common.Hash
Header *types.Header
Td *big.Int
Proof []rlp.RawValue
}
// StoreResult stores the retrieved data in local database
func (req *ChtRequest) StoreResult(db ethdb.Database) {
// if there is a canonical hash, there is a header too
core.WriteHeader(db, req.Header)
hash, num := req.Header.Hash(), req.Header.Number.Uint64()
core.WriteTd(db, hash, num, req.Td)
core.WriteCanonicalHash(db, hash, num)
//storeProof(db, req.Proof)
}