aboutsummaryrefslogtreecommitdiff
path: root/consensus/dummy/consensus.go
blob: 2a9441d5027b878f1c090c09eec349211c308a93 (plain) (blame)
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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
package dummy

import (
    "fmt"
    "time"
    "errors"
    "runtime"
    "math/big"
    "golang.org/x/crypto/sha3"

    "github.com/ethereum/go-ethereum/consensus"
    "github.com/ethereum/go-ethereum/core/types"
    "github.com/ethereum/go-ethereum/core/state"
    "github.com/ethereum/go-ethereum/params"
    "github.com/ethereum/go-ethereum/common"
    "github.com/ethereum/go-ethereum/rlp"
    "github.com/ethereum/go-ethereum/rpc"
)

type DummyEngine struct {
}

var (
    allowedFutureBlockTime    = 15 * time.Second  // Max time from current time allowed for blocks, before they're considered future blocks
)

var (
    errZeroBlockTime     = errors.New("timestamp equals parent's")
)

// modified from consensus.go
func (self *DummyEngine) verifyHeader(chain consensus.ChainReader, header, parent *types.Header, uncle bool, seal bool) error {
    // Ensure that the header's extra-data section is of a reasonable size
    if uint64(len(header.Extra)) > params.MaximumExtraDataSize {
        return fmt.Errorf("extra-data too long: %d > %d", len(header.Extra), params.MaximumExtraDataSize)
    }
    // Verify the header's timestamp
    if !uncle {
        if header.Time > uint64(time.Now().Add(allowedFutureBlockTime).Unix()) {
            return consensus.ErrFutureBlock
        }
    }
    if header.Time <= parent.Time {
        return errZeroBlockTime
    }
    // Verify that the gas limit is <= 2^63-1
    cap := uint64(0x7fffffffffffffff)
    if header.GasLimit > cap {
        return fmt.Errorf("invalid gasLimit: have %v, max %v", header.GasLimit, cap)
    }
    // Verify that the gasUsed is <= gasLimit
    if header.GasUsed > header.GasLimit {
        return fmt.Errorf("invalid gasUsed: have %d, gasLimit %d", header.GasUsed, header.GasLimit)
    }

    // Verify that the gas limit remains within allowed bounds
    diff := int64(parent.GasLimit) - int64(header.GasLimit)
    if diff < 0 {
        diff *= -1
    }
    limit := parent.GasLimit / params.GasLimitBoundDivisor

    if uint64(diff) >= limit || header.GasLimit < params.MinGasLimit {
        return fmt.Errorf("invalid gas limit: have %d, want %d += %d", header.GasLimit, parent.GasLimit, limit)
    }
    // Verify that the block number is parent's +1
    if diff := new(big.Int).Sub(header.Number, parent.Number); diff.Cmp(big.NewInt(1)) != 0 {
        return consensus.ErrInvalidNumber
    }
    // Verify the engine specific seal securing the block
    if seal {
        if err := self.VerifySeal(chain, header); err != nil {
            return err
        }
    }
    return nil
}

func (self *DummyEngine) verifyHeaderWorker(chain consensus.ChainReader, headers []*types.Header, seals []bool, index int) error {
    var parent *types.Header
    if index == 0 {
        parent = chain.GetHeader(headers[0].ParentHash, headers[0].Number.Uint64()-1)
    } else if headers[index-1].Hash() == headers[index].ParentHash {
        parent = headers[index-1]
    }
    if parent == nil {
        return consensus.ErrUnknownAncestor
    }
    if chain.GetHeader(headers[index].Hash(), headers[index].Number.Uint64()) != nil {
        return nil // known block
    }
    return self.verifyHeader(chain, headers[index], parent, false, seals[index])
}

func (self *DummyEngine) Author(header *types.Header) (common.Address, error) {
    return header.Coinbase, nil
}

func (self *DummyEngine) VerifyHeader(chain consensus.ChainReader, header *types.Header, seal bool) error {
    // Short circuit if the header is known, or it's parent not
    number := header.Number.Uint64()
    if chain.GetHeader(header.Hash(), number) != nil {
        return nil
    }
    parent := chain.GetHeader(header.ParentHash, number-1)
    if parent == nil {
        return consensus.ErrUnknownAncestor
    }
    // Sanity checks passed, do a proper verification
    return self.verifyHeader(chain, header, parent, false, seal)
}

func (self *DummyEngine) VerifyHeaders(chain consensus.ChainReader, headers []*types.Header, seals []bool) (chan<- struct{}, <-chan error) {
    // Spawn as many workers as allowed threads
    workers := runtime.GOMAXPROCS(0)
    if len(headers) < workers {
        workers = len(headers)
    }

    // Create a task channel and spawn the verifiers
    var (
        inputs = make(chan int)
        done   = make(chan int, workers)
        errors = make([]error, len(headers))
        abort  = make(chan struct{})
    )
    for i := 0; i < workers; i++ {
        go func() {
            for index := range inputs {
                errors[index] = self.verifyHeaderWorker(chain, headers, seals, index)
                done <- index
            }
        }()
    }

    errorsOut := make(chan error, len(headers))
    go func() {
        defer close(inputs)
        var (
            in, out = 0, 0
            checked = make([]bool, len(headers))
            inputs  = inputs
        )
        for {
            select {
            case inputs <- in:
                if in++; in == len(headers) {
                    // Reached end of headers. Stop sending to workers.
                    inputs = nil
                }
            case index := <-done:
                for checked[index] = true; checked[out]; out++ {
                    errorsOut <- errors[out]
                    if out == len(headers)-1 {
                        return
                    }
                }
            case <-abort:
                return
            }
        }
    }()
    return abort, errorsOut
}

func (self *DummyEngine) VerifyUncles(chain consensus.ChainReader, block *types.Block) error {
    return nil
}

func (self *DummyEngine) VerifySeal(chain consensus.ChainReader, header *types.Header) error {
    return nil
}

func (self *DummyEngine) Prepare(chain consensus.ChainReader, header *types.Header) error {
    header.Difficulty = big.NewInt(1)
    return nil
}

func (self *DummyEngine) Finalize(chain consensus.ChainReader, header *types.Header, state *state.StateDB, txs []*types.Transaction,
uncles []*types.Header) {
    // commit the final state root
    header.Root = state.IntermediateRoot(chain.Config().IsEIP158(header.Number))
}

func (self *DummyEngine) FinalizeAndAssemble(chain consensus.ChainReader, header *types.Header, state *state.StateDB, txs []*types.Transaction,
uncles []*types.Header, receipts []*types.Receipt) (*types.Block, error) {
    // commit the final state root
    header.Root = state.IntermediateRoot(chain.Config().IsEIP158(header.Number))

    // Header seems complete, assemble into a block and return
    return types.NewBlock(header, txs, uncles, receipts), nil
}

func (self *DummyEngine) Seal(chain consensus.ChainReader, block *types.Block, results chan<- *types.Block, stop <-chan struct{}) error {
    time.Sleep(1000 * time.Millisecond)
    fmt.Printf("sealed %s\n", block.ParentHash().String())
    results <- block
    return nil
}

func (self *DummyEngine) SealHash(header *types.Header) (hash common.Hash) {
    hasher := sha3.NewLegacyKeccak256()

    rlp.Encode(hasher, []interface{}{
        header.ParentHash,
        header.UncleHash,
        header.Coinbase,
        header.Root,
        header.TxHash,
        header.ReceiptHash,
        header.Bloom,
        header.Difficulty,
        header.Number,
        header.GasLimit,
        header.GasUsed,
        header.Time,
        header.Extra,
    })
    hasher.Sum(hash[:0])
    return hash
}

func (self *DummyEngine) CalcDifficulty(chain consensus.ChainReader, time uint64, parent *types.Header) *big.Int {
    return big.NewInt(1)
}

func (self *DummyEngine) APIs(chain consensus.ChainReader) []rpc.API {
    retur