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642 lines
23 KiB
Go
642 lines
23 KiB
Go
// Copyright 2017 The go-ethereum Authors
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// This file is part of the go-ethereum library.
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//
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// The go-ethereum library is free software: you can redistribute it and/or modify
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// it under the terms of the GNU Lesser General Public License as published by
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// the Free Software Foundation, either version 3 of the License, or
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// (at your option) any later version.
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//
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// The go-ethereum library is distributed in the hope that it will be useful,
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// but WITHOUT ANY WARRANTY; without even the implied warranty of
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// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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// GNU Lesser General Public License for more details.
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//
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// You should have received a copy of the GNU Lesser General Public License
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// along with the go-ethereum library. If not, see <http://www.gnu.org/licenses/>.
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package ethash
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import (
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"bytes"
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"errors"
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"fmt"
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"math/big"
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"runtime"
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"time"
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mapset "github.com/deckarep/golang-set"
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"github.com/ethereum/go-ethereum/common"
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"github.com/ethereum/go-ethereum/common/math"
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"github.com/ethereum/go-ethereum/consensus"
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"github.com/ethereum/go-ethereum/consensus/misc"
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"github.com/ethereum/go-ethereum/core/state"
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"github.com/ethereum/go-ethereum/core/types"
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"github.com/ethereum/go-ethereum/params"
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"github.com/ethereum/go-ethereum/rlp"
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"github.com/ethereum/go-ethereum/trie"
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"golang.org/x/crypto/sha3"
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)
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// Ethash proof-of-work protocol constants.
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var (
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FrontierBlockReward = big.NewInt(5e+18) // Block reward in wei for successfully mining a block
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ByzantiumBlockReward = big.NewInt(3e+18) // Block reward in wei for successfully mining a block upward from Byzantium
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ConstantinopleBlockReward = big.NewInt(2e+18) // Block reward in wei for successfully mining a block upward from Constantinople
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maxUncles = 2 // Maximum number of uncles allowed in a single block
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allowedFutureBlockTimeSeconds = int64(15) // Max seconds from current time allowed for blocks, before they're considered future blocks
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// calcDifficultyEip2384 is the difficulty adjustment algorithm as specified by EIP 2384.
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// It offsets the bomb 4M blocks from Constantinople, so in total 9M blocks.
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// Specification EIP-2384: https://eips.ethereum.org/EIPS/eip-2384
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calcDifficultyEip2384 = makeDifficultyCalculator(big.NewInt(9000000))
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// calcDifficultyConstantinople is the difficulty adjustment algorithm for Constantinople.
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// It returns the difficulty that a new block should have when created at time given the
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// parent block's time and difficulty. The calculation uses the Byzantium rules, but with
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// bomb offset 5M.
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// Specification EIP-1234: https://eips.ethereum.org/EIPS/eip-1234
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calcDifficultyConstantinople = makeDifficultyCalculator(big.NewInt(5000000))
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// calcDifficultyByzantium is the difficulty adjustment algorithm. It returns
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// the difficulty that a new block should have when created at time given the
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// parent block's time and difficulty. The calculation uses the Byzantium rules.
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// Specification EIP-649: https://eips.ethereum.org/EIPS/eip-649
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calcDifficultyByzantium = makeDifficultyCalculator(big.NewInt(3000000))
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)
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// Various error messages to mark blocks invalid. These should be private to
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// prevent engine specific errors from being referenced in the remainder of the
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// codebase, inherently breaking if the engine is swapped out. Please put common
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// error types into the consensus package.
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var (
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errOlderBlockTime = errors.New("timestamp older than parent")
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errTooManyUncles = errors.New("too many uncles")
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errDuplicateUncle = errors.New("duplicate uncle")
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errUncleIsAncestor = errors.New("uncle is ancestor")
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errDanglingUncle = errors.New("uncle's parent is not ancestor")
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errInvalidDifficulty = errors.New("non-positive difficulty")
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errInvalidMixDigest = errors.New("invalid mix digest")
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errInvalidPoW = errors.New("invalid proof-of-work")
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)
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// Author implements consensus.Engine, returning the header's coinbase as the
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// proof-of-work verified author of the block.
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func (ethash *Ethash) Author(header *types.Header) (common.Address, error) {
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return header.Coinbase, nil
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}
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// VerifyHeader checks whether a header conforms to the consensus rules of the
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// stock Ethereum ethash engine.
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func (ethash *Ethash) VerifyHeader(chain consensus.ChainHeaderReader, header *types.Header, seal bool) error {
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// If we're running a full engine faking, accept any input as valid
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if ethash.config.PowMode == ModeFullFake {
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return nil
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}
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// Short circuit if the header is known, or its parent not
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number := header.Number.Uint64()
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if chain.GetHeader(header.Hash(), number) != nil {
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return nil
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}
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parent := chain.GetHeader(header.ParentHash, number-1)
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if parent == nil {
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return consensus.ErrUnknownAncestor
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}
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// Sanity checks passed, do a proper verification
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return ethash.verifyHeader(chain, header, parent, false, seal, time.Now().Unix())
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}
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// VerifyHeaders is similar to VerifyHeader, but verifies a batch of headers
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// concurrently. The method returns a quit channel to abort the operations and
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// a results channel to retrieve the async verifications.
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func (ethash *Ethash) VerifyHeaders(chain consensus.ChainHeaderReader, headers []*types.Header, seals []bool) (chan<- struct{}, <-chan error) {
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// If we're running a full engine faking, accept any input as valid
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if ethash.config.PowMode == ModeFullFake || len(headers) == 0 {
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abort, results := make(chan struct{}), make(chan error, len(headers))
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for i := 0; i < len(headers); i++ {
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results <- nil
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}
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return abort, results
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}
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// Spawn as many workers as allowed threads
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workers := runtime.GOMAXPROCS(0)
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if len(headers) < workers {
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workers = len(headers)
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}
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// Create a task channel and spawn the verifiers
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var (
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inputs = make(chan int)
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done = make(chan int, workers)
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errors = make([]error, len(headers))
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abort = make(chan struct{})
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unixNow = time.Now().Unix()
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)
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for i := 0; i < workers; i++ {
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go func() {
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for index := range inputs {
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errors[index] = ethash.verifyHeaderWorker(chain, headers, seals, index, unixNow)
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done <- index
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}
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}()
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}
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errorsOut := make(chan error, len(headers))
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go func() {
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defer close(inputs)
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var (
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in, out = 0, 0
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checked = make([]bool, len(headers))
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inputs = inputs
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)
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for {
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select {
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case inputs <- in:
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if in++; in == len(headers) {
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// Reached end of headers. Stop sending to workers.
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inputs = nil
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}
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case index := <-done:
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for checked[index] = true; checked[out]; out++ {
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errorsOut <- errors[out]
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if out == len(headers)-1 {
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return
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}
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}
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case <-abort:
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return
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}
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}
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}()
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return abort, errorsOut
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}
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func (ethash *Ethash) verifyHeaderWorker(chain consensus.ChainHeaderReader, headers []*types.Header, seals []bool, index int, unixNow int64) error {
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var parent *types.Header
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if index == 0 {
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parent = chain.GetHeader(headers[0].ParentHash, headers[0].Number.Uint64()-1)
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} else if headers[index-1].Hash() == headers[index].ParentHash {
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parent = headers[index-1]
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}
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if parent == nil {
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return consensus.ErrUnknownAncestor
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}
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return ethash.verifyHeader(chain, headers[index], parent, false, seals[index], unixNow)
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}
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// VerifyUncles verifies that the given block's uncles conform to the consensus
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// rules of the stock Ethereum ethash engine.
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func (ethash *Ethash) VerifyUncles(chain consensus.ChainReader, block *types.Block) error {
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// If we're running a full engine faking, accept any input as valid
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if ethash.config.PowMode == ModeFullFake {
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return nil
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}
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// Verify that there are at most 2 uncles included in this block
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if len(block.Uncles()) > maxUncles {
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return errTooManyUncles
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}
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if len(block.Uncles()) == 0 {
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return nil
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}
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// Gather the set of past uncles and ancestors
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uncles, ancestors := mapset.NewSet(), make(map[common.Hash]*types.Header)
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number, parent := block.NumberU64()-1, block.ParentHash()
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for i := 0; i < 7; i++ {
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ancestor := chain.GetBlock(parent, number)
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if ancestor == nil {
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break
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}
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ancestors[ancestor.Hash()] = ancestor.Header()
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for _, uncle := range ancestor.Uncles() {
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uncles.Add(uncle.Hash())
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}
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parent, number = ancestor.ParentHash(), number-1
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}
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ancestors[block.Hash()] = block.Header()
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uncles.Add(block.Hash())
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// Verify each of the uncles that it's recent, but not an ancestor
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for _, uncle := range block.Uncles() {
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// Make sure every uncle is rewarded only once
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hash := uncle.Hash()
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if uncles.Contains(hash) {
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return errDuplicateUncle
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}
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uncles.Add(hash)
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// Make sure the uncle has a valid ancestry
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if ancestors[hash] != nil {
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return errUncleIsAncestor
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}
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if ancestors[uncle.ParentHash] == nil || uncle.ParentHash == block.ParentHash() {
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return errDanglingUncle
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}
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if err := ethash.verifyHeader(chain, uncle, ancestors[uncle.ParentHash], true, true, time.Now().Unix()); err != nil {
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return err
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}
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}
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return nil
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}
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// verifyHeader checks whether a header conforms to the consensus rules of the
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// stock Ethereum ethash engine.
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// See YP section 4.3.4. "Block Header Validity"
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func (ethash *Ethash) verifyHeader(chain consensus.ChainHeaderReader, header, parent *types.Header, uncle bool, seal bool, unixNow int64) error {
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// Ensure that the header's extra-data section is of a reasonable size
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if uint64(len(header.Extra)) > params.MaximumExtraDataSize {
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return fmt.Errorf("extra-data too long: %d > %d", len(header.Extra), params.MaximumExtraDataSize)
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}
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// Verify the header's timestamp
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if !uncle {
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if header.Time > uint64(unixNow+allowedFutureBlockTimeSeconds) {
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return consensus.ErrFutureBlock
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}
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}
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if header.Time <= parent.Time {
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return errOlderBlockTime
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}
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// Verify the block's difficulty based on its timestamp and parent's difficulty
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expected := ethash.CalcDifficulty(chain, header.Time, parent)
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if expected.Cmp(header.Difficulty) != 0 {
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return fmt.Errorf("invalid difficulty: have %v, want %v", header.Difficulty, expected)
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}
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// Verify that the gas limit is <= 2^63-1
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cap := uint64(0x7fffffffffffffff)
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if header.GasLimit > cap {
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return fmt.Errorf("invalid gasLimit: have %v, max %v", header.GasLimit, cap)
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}
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// Verify that the gasUsed is <= gasLimit
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if header.GasUsed > header.GasLimit {
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return fmt.Errorf("invalid gasUsed: have %d, gasLimit %d", header.GasUsed, header.GasLimit)
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}
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// Verify that the gas limit remains within allowed bounds
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diff := int64(parent.GasLimit) - int64(header.GasLimit)
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if diff < 0 {
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diff *= -1
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}
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limit := parent.GasLimit / params.GasLimitBoundDivisor
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if uint64(diff) >= limit || header.GasLimit < params.MinGasLimit {
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return fmt.Errorf("invalid gas limit: have %d, want %d += %d", header.GasLimit, parent.GasLimit, limit)
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}
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// Verify that the block number is parent's +1
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if diff := new(big.Int).Sub(header.Number, parent.Number); diff.Cmp(big.NewInt(1)) != 0 {
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return consensus.ErrInvalidNumber
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}
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// Verify the engine specific seal securing the block
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if seal {
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if err := ethash.verifySeal(chain, header, false); err != nil {
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return err
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}
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}
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// If all checks passed, validate any special fields for hard forks
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if err := misc.VerifyDAOHeaderExtraData(chain.Config(), header); err != nil {
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return err
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}
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if err := misc.VerifyForkHashes(chain.Config(), header, uncle); err != nil {
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return err
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}
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return nil
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}
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// CalcDifficulty is the difficulty adjustment algorithm. It returns
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// the difficulty that a new block should have when created at time
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// given the parent block's time and difficulty.
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func (ethash *Ethash) CalcDifficulty(chain consensus.ChainHeaderReader, time uint64, parent *types.Header) *big.Int {
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return CalcDifficulty(chain.Config(), time, parent)
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}
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// CalcDifficulty is the difficulty adjustment algorithm. It returns
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// the difficulty that a new block should have when created at time
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// given the parent block's time and difficulty.
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func CalcDifficulty(config *params.ChainConfig, time uint64, parent *types.Header) *big.Int {
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next := new(big.Int).Add(parent.Number, big1)
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switch {
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case config.IsMuirGlacier(next):
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return calcDifficultyEip2384(time, parent)
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case config.IsConstantinople(next):
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return calcDifficultyConstantinople(time, parent)
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case config.IsByzantium(next):
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return calcDifficultyByzantium(time, parent)
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case config.IsHomestead(next):
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return calcDifficultyHomestead(time, parent)
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default:
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return calcDifficultyFrontier(time, parent)
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}
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}
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// Some weird constants to avoid constant memory allocs for them.
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var (
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expDiffPeriod = big.NewInt(100000)
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big1 = big.NewInt(1)
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big2 = big.NewInt(2)
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big9 = big.NewInt(9)
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big10 = big.NewInt(10)
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bigMinus99 = big.NewInt(-99)
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)
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// makeDifficultyCalculator creates a difficultyCalculator with the given bomb-delay.
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// the difficulty is calculated with Byzantium rules, which differs from Homestead in
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// how uncles affect the calculation
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func makeDifficultyCalculator(bombDelay *big.Int) func(time uint64, parent *types.Header) *big.Int {
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// Note, the calculations below looks at the parent number, which is 1 below
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// the block number. Thus we remove one from the delay given
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bombDelayFromParent := new(big.Int).Sub(bombDelay, big1)
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return func(time uint64, parent *types.Header) *big.Int {
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// https://github.com/ethereum/EIPs/issues/100.
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// algorithm:
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// diff = (parent_diff +
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// (parent_diff / 2048 * max((2 if len(parent.uncles) else 1) - ((timestamp - parent.timestamp) // 9), -99))
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// ) + 2^(periodCount - 2)
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bigTime := new(big.Int).SetUint64(time)
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bigParentTime := new(big.Int).SetUint64(parent.Time)
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// holds intermediate values to make the algo easier to read & audit
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x := new(big.Int)
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y := new(big.Int)
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// (2 if len(parent_uncles) else 1) - (block_timestamp - parent_timestamp) // 9
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x.Sub(bigTime, bigParentTime)
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x.Div(x, big9)
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if parent.UncleHash == types.EmptyUncleHash {
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x.Sub(big1, x)
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} else {
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x.Sub(big2, x)
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}
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// max((2 if len(parent_uncles) else 1) - (block_timestamp - parent_timestamp) // 9, -99)
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if x.Cmp(bigMinus99) < 0 {
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x.Set(bigMinus99)
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}
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// parent_diff + (parent_diff / 2048 * max((2 if len(parent.uncles) else 1) - ((timestamp - parent.timestamp) // 9), -99))
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y.Div(parent.Difficulty, params.DifficultyBoundDivisor)
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x.Mul(y, x)
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x.Add(parent.Difficulty, x)
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// minimum difficulty can ever be (before exponential factor)
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if x.Cmp(params.MinimumDifficulty) < 0 {
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x.Set(params.MinimumDifficulty)
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}
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// calculate a fake block number for the ice-age delay
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// Specification: https://eips.ethereum.org/EIPS/eip-1234
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fakeBlockNumber := new(big.Int)
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if parent.Number.Cmp(bombDelayFromParent) >= 0 {
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fakeBlockNumber = fakeBlockNumber.Sub(parent.Number, bombDelayFromParent)
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}
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// for the exponential factor
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periodCount := fakeBlockNumber
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periodCount.Div(periodCount, expDiffPeriod)
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// the exponential factor, commonly referred to as "the bomb"
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// diff = diff + 2^(periodCount - 2)
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if periodCount.Cmp(big1) > 0 {
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y.Sub(periodCount, big2)
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y.Exp(big2, y, nil)
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x.Add(x, y)
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}
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return x
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}
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}
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// calcDifficultyHomestead is the difficulty adjustment algorithm. It returns
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// the difficulty that a new block should have when created at time given the
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// parent block's time and difficulty. The calculation uses the Homestead rules.
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func calcDifficultyHomestead(time uint64, parent *types.Header) *big.Int {
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// https://github.com/ethereum/EIPs/blob/master/EIPS/eip-2.md
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// algorithm:
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// diff = (parent_diff +
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// (parent_diff / 2048 * max(1 - (block_timestamp - parent_timestamp) // 10, -99))
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// ) + 2^(periodCount - 2)
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bigTime := new(big.Int).SetUint64(time)
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bigParentTime := new(big.Int).SetUint64(parent.Time)
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// holds intermediate values to make the algo easier to read & audit
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x := new(big.Int)
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y := new(big.Int)
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// 1 - (block_timestamp - parent_timestamp) // 10
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x.Sub(bigTime, bigParentTime)
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x.Div(x, big10)
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x.Sub(big1, x)
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// max(1 - (block_timestamp - parent_timestamp) // 10, -99)
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if x.Cmp(bigMinus99) < 0 {
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x.Set(bigMinus99)
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}
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// (parent_diff + parent_diff // 2048 * max(1 - (block_timestamp - parent_timestamp) // 10, -99))
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y.Div(parent.Difficulty, params.DifficultyBoundDivisor)
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x.Mul(y, x)
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x.Add(parent.Difficulty, x)
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// minimum difficulty can ever be (before exponential factor)
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if x.Cmp(params.MinimumDifficulty) < 0 {
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x.Set(params.MinimumDifficulty)
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}
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// for the exponential factor
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periodCount := new(big.Int).Add(parent.Number, big1)
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periodCount.Div(periodCount, expDiffPeriod)
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// the exponential factor, commonly referred to as "the bomb"
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// diff = diff + 2^(periodCount - 2)
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if periodCount.Cmp(big1) > 0 {
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y.Sub(periodCount, big2)
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y.Exp(big2, y, nil)
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x.Add(x, y)
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}
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return x
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}
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// calcDifficultyFrontier is the difficulty adjustment algorithm. It returns the
|
|
// difficulty that a new block should have when created at time given the parent
|
|
// block's time and difficulty. The calculation uses the Frontier rules.
|
|
func calcDifficultyFrontier(time uint64, parent *types.Header) *big.Int {
|
|
diff := new(big.Int)
|
|
adjust := new(big.Int).Div(parent.Difficulty, params.DifficultyBoundDivisor)
|
|
bigTime := new(big.Int)
|
|
bigParentTime := new(big.Int)
|
|
|
|
bigTime.SetUint64(time)
|
|
bigParentTime.SetUint64(parent.Time)
|
|
|
|
if bigTime.Sub(bigTime, bigParentTime).Cmp(params.DurationLimit) < 0 {
|
|
diff.Add(parent.Difficulty, adjust)
|
|
} else {
|
|
diff.Sub(parent.Difficulty, adjust)
|
|
}
|
|
if diff.Cmp(params.MinimumDifficulty) < 0 {
|
|
diff.Set(params.MinimumDifficulty)
|
|
}
|
|
|
|
periodCount := new(big.Int).Add(parent.Number, big1)
|
|
periodCount.Div(periodCount, expDiffPeriod)
|
|
if periodCount.Cmp(big1) > 0 {
|
|
// diff = diff + 2^(periodCount - 2)
|
|
expDiff := periodCount.Sub(periodCount, big2)
|
|
expDiff.Exp(big2, expDiff, nil)
|
|
diff.Add(diff, expDiff)
|
|
diff = math.BigMax(diff, params.MinimumDifficulty)
|
|
}
|
|
return diff
|
|
}
|
|
|
|
// Exported for fuzzing
|
|
var FrontierDifficultyCalulator = calcDifficultyFrontier
|
|
var HomesteadDifficultyCalulator = calcDifficultyHomestead
|
|
var DynamicDifficultyCalculator = makeDifficultyCalculator
|
|
|
|
// verifySeal checks whether a block satisfies the PoW difficulty requirements,
|
|
// either using the usual ethash cache for it, or alternatively using a full DAG
|
|
// to make remote mining fast.
|
|
func (ethash *Ethash) verifySeal(chain consensus.ChainHeaderReader, header *types.Header, fulldag bool) error {
|
|
// If we're running a fake PoW, accept any seal as valid
|
|
if ethash.config.PowMode == ModeFake || ethash.config.PowMode == ModeFullFake {
|
|
time.Sleep(ethash.fakeDelay)
|
|
if ethash.fakeFail == header.Number.Uint64() {
|
|
return errInvalidPoW
|
|
}
|
|
return nil
|
|
}
|
|
// If we're running a shared PoW, delegate verification to it
|
|
if ethash.shared != nil {
|
|
return ethash.shared.verifySeal(chain, header, fulldag)
|
|
}
|
|
// Ensure that we have a valid difficulty for the block
|
|
if header.Difficulty.Sign() <= 0 {
|
|
return errInvalidDifficulty
|
|
}
|
|
// Recompute the digest and PoW values
|
|
number := header.Number.Uint64()
|
|
|
|
var (
|
|
digest []byte
|
|
result []byte
|
|
)
|
|
// If fast-but-heavy PoW verification was requested, use an ethash dataset
|
|
if fulldag {
|
|
dataset := ethash.dataset(number, true)
|
|
if dataset.generated() {
|
|
digest, result = hashimotoFull(dataset.dataset, ethash.SealHash(header).Bytes(), header.Nonce.Uint64())
|
|
|
|
// Datasets are unmapped in a finalizer. Ensure that the dataset stays alive
|
|
// until after the call to hashimotoFull so it's not unmapped while being used.
|
|
runtime.KeepAlive(dataset)
|
|
} else {
|
|
// Dataset not yet generated, don't hang, use a cache instead
|
|
fulldag = false
|
|
}
|
|
}
|
|
// If slow-but-light PoW verification was requested (or DAG not yet ready), use an ethash cache
|
|
if !fulldag {
|
|
cache := ethash.cache(number)
|
|
|
|
size := datasetSize(number)
|
|
if ethash.config.PowMode == ModeTest {
|
|
size = 32 * 1024
|
|
}
|
|
digest, result = hashimotoLight(size, cache.cache, ethash.SealHash(header).Bytes(), header.Nonce.Uint64())
|
|
|
|
// Caches are unmapped in a finalizer. Ensure that the cache stays alive
|
|
// until after the call to hashimotoLight so it's not unmapped while being used.
|
|
runtime.KeepAlive(cache)
|
|
}
|
|
// Verify the calculated values against the ones provided in the header
|
|
if !bytes.Equal(header.MixDigest[:], digest) {
|
|
return errInvalidMixDigest
|
|
}
|
|
target := new(big.Int).Div(two256, header.Difficulty)
|
|
if new(big.Int).SetBytes(result).Cmp(target) > 0 {
|
|
return errInvalidPoW
|
|
}
|
|
return nil
|
|
}
|
|
|
|
// Prepare implements consensus.Engine, initializing the difficulty field of a
|
|
// header to conform to the ethash protocol. The changes are done inline.
|
|
func (ethash *Ethash) Prepare(chain consensus.ChainHeaderReader, header *types.Header) error {
|
|
parent := chain.GetHeader(header.ParentHash, header.Number.Uint64()-1)
|
|
if parent == nil {
|
|
return consensus.ErrUnknownAncestor
|
|
}
|
|
header.Difficulty = ethash.CalcDifficulty(chain, header.Time, parent)
|
|
return nil
|
|
}
|
|
|
|
// Finalize implements consensus.Engine, accumulating the block and uncle rewards,
|
|
// setting the final state on the header
|
|
func (ethash *Ethash) Finalize(chain consensus.ChainHeaderReader, header *types.Header, state *state.StateDB, txs []*types.Transaction, uncles []*types.Header) {
|
|
// Accumulate any block and uncle rewards and commit the final state root
|
|
accumulateRewards(chain.Config(), state, header, uncles)
|
|
header.Root = state.IntermediateRoot(chain.Config().IsEIP158(header.Number))
|
|
}
|
|
|
|
// FinalizeAndAssemble implements consensus.Engine, accumulating the block and
|
|
// uncle rewards, setting the final state and assembling the block.
|
|
func (ethash *Ethash) FinalizeAndAssemble(chain consensus.ChainHeaderReader, header *types.Header, state *state.StateDB, txs []*types.Transaction, uncles []*types.Header, receipts []*types.Receipt) (*types.Block, error) {
|
|
// Finalize block
|
|
ethash.Finalize(chain, header, state, txs, uncles)
|
|
|
|
// Header seems complete, assemble into a block and return
|
|
return types.NewBlock(header, txs, uncles, receipts, trie.NewStackTrie(nil)), nil
|
|
}
|
|
|
|
// SealHash returns the hash of a block prior to it being sealed.
|
|
func (ethash *Ethash) 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
|
|
}
|
|
|
|
// Some weird constants to avoid constant memory allocs for them.
|
|
var (
|
|
big8 = big.NewInt(8)
|
|
big32 = big.NewInt(32)
|
|
)
|
|
|
|
// AccumulateRewards credits the coinbase of the given block with the mining
|
|
// reward. The total reward consists of the static block reward and rewards for
|
|
// included uncles. The coinbase of each uncle block is also rewarded.
|
|
func accumulateRewards(config *params.ChainConfig, state *state.StateDB, header *types.Header, uncles []*types.Header) {
|
|
// Select the correct block reward based on chain progression
|
|
blockReward := FrontierBlockReward
|
|
if config.IsByzantium(header.Number) {
|
|
blockReward = ByzantiumBlockReward
|
|
}
|
|
if config.IsConstantinople(header.Number) {
|
|
blockReward = ConstantinopleBlockReward
|
|
}
|
|
// Accumulate the rewards for the miner and any included uncles
|
|
reward := new(big.Int).Set(blockReward)
|
|
r := new(big.Int)
|
|
for _, uncle := range uncles {
|
|
r.Add(uncle.Number, big8)
|
|
r.Sub(r, header.Number)
|
|
r.Mul(r, blockReward)
|
|
r.Div(r, big8)
|
|
state.AddBalance(uncle.Coinbase, r)
|
|
|
|
r.Div(blockReward, big32)
|
|
reward.Add(reward, r)
|
|
}
|
|
state.AddBalance(header.Coinbase, reward)
|
|
}
|