core

package
v0.1.3 Latest Latest
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 Go to latest Published: Mar 14, 2019 License: GPL-3.0, GPL-3.0 Imports: 37 Imported by: 0

Documentation

Overview

Package core implements the Ethereum consensus protocol.

Index

Examples

Constants

View Source 
const (

	// BlockChainVersion ensures that an incompatible database forces a resync from scratch.
	BlockChainVersion = 3
)

Variables

View Source 
var (
	// ErrKnownBlock is returned when a block to import is already known locally.
	ErrKnownBlock = errors.New("block already known")

	// ErrGasLimitReached is returned by the gas pool if the amount of gas required
	// by a transaction is higher than what's left in the block.
	ErrGasLimitReached = errors.New("gas limit reached")

	// ErrBlacklistedHash is returned if a block to import is on the blacklist.
	ErrBlacklistedHash = errors.New("blacklisted hash")

	// ErrNonceTooHigh is returned if the nonce of a transaction is higher than the
	// next one expected based on the local chain.
	ErrNonceTooHigh = errors.New("nonce too high")
)
View Source 
var (
	// ErrInvalidSender is returned if the transaction contains an invalid signature.
	ErrInvalidSender = errors.New("invalid sender")

	// ErrNonceTooLow is returned if the nonce of a transaction is lower than the
	// one present in the local chain.
	ErrNonceTooLow = errors.New("nonce too low")

	// ErrUnderpriced is returned if a transaction's gas price is below the minimum
	// configured for the transaction pool.
	ErrUnderpriced = errors.New("transaction underpriced")

	// ErrReplaceUnderpriced is returned if a transaction is attempted to be replaced
	// with a different one without the required price bump.
	ErrReplaceUnderpriced = errors.New("replacement transaction underpriced")

	// ErrInsufficientFunds is returned if the total cost of executing a transaction
	// is higher than the balance of the user's account.
	ErrInsufficientFunds = errors.New("insufficient funds for gas * price + value")

	// ErrIntrinsicGas is returned if the transaction is specified to use less gas
	// than required to start the invocation.
	ErrIntrinsicGas = errors.New("intrinsic gas too low")

	// ErrGasLimit is returned if a transaction's requested gas limit exceeds the
	// maximum allowance of the current block.
	ErrGasLimit = errors.New("exceeds block gas limit")

	// ErrNegativeValue is a sanity error to ensure noone is able to specify a
	// transaction with a negative value.
	ErrNegativeValue = errors.New("negative value")

	// ErrOversizedData is returned if the input data of a transaction is greater
	// than some meaningful limit a user might use. This is not a consensus error
	// making the transaction invalid, rather a DOS protection.
	ErrOversizedData = errors.New("oversized data")
)
View Source 
var BadHashes = map[common.Hash]bool{
	common.HexToHash("05bef30ef572270f654746da22639a7a0c97dd97a7050b9e252391996aaeb689"): true,
	common.HexToHash("7d05d08cbc596a2e5e4f13b80a743e53e09221b5323c3a61946b20873e58583f"): true,
}

BadHashes represent a set of manually tracked bad hashes (usually hard forks)

View Source 
var DefaultTxPoolConfig = TxPoolConfig{
	Journal:   "transactions.rlp",
	Rejournal: time.Hour,

	PriceLimit: 1,
	PriceBump:  10,

	AccountSlots: 16,
	GlobalSlots:  4096,
	AccountQueue: 64,
	GlobalQueue:  1024,

	Lifetime: 3 * time.Hour,
}

DefaultTxPoolConfig contains the default configurations for the transaction pool.

View Source 
var (
	ErrNoGenesis = errors.New("Genesis not found in chain")
)

Functions

func ApplyMessage 

func ApplyMessage(evm *vm.EVM, msg Message, gp *GasPool) ([]byte, uint64, bool, error)

ApplyMessage computes the new state by applying the given message against the old state within the environment.

ApplyMessage returns the bytes returned by any EVM execution (if it took place), the gas used (which includes gas refunds) and an error if it failed. An error always indicates a core error meaning that the message would always fail for that particular state and would never be accepted within a block.

func ApplyTransaction 

func ApplyTransaction(config *params.ChainConfig, bc *BlockChain, author *common.Address, gp *GasPool, statedb *state.StateDB, header *types.Header, tx *types.Transaction, usedGas *uint64, cfg vm.Config) (*types.Receipt, uint64, error)

ApplyTransaction attempts to apply a transaction to the given state database and uses the input parameters for its environment. It returns the receipt for the transaction, gas used and an error if the transaction failed, indicating the block was invalid.

func CalcGasLimit 

func CalcGasLimit(parent *types.Block) uint64

CalcGasLimit computes the gas limit of the next block after parent. This is miner strategy, not consensus protocol.

func CanTransfer 

func CanTransfer(db vm.StateDB, addr common.Address, amount *big.Int) bool

CanTransfer checks wether there are enough funds in the address' account to make a transfer. This does not take the necessary gas in to account to make the transfer valid.

func GenerateChain 

func GenerateChain(config *params.ChainConfig, parent *types.Block, engine consensus.Engine, db ethdb.Database, n int, gen func(int, *BlockGen)) ([]*types.Block, []types.Receipts)

GenerateChain creates a chain of n blocks. The first block's parent will be the provided parent. db is used to store intermediate states and should contain the parent's state trie.

The generator function is called with a new block generator for every block. Any transactions and uncles added to the generator become part of the block. If gen is nil, the blocks will be empty and their coinbase will be the zero address.

Blocks created by GenerateChain do not contain valid proof of work values. Inserting them into BlockChain requires use of FakePow or a similar non-validating proof of work implementation.

Example 
var (
	key1, _ = crypto.HexToECDSA("b71c71a67e1177ad4e901695e1b4b9ee17ae16c6668d313eac2f96dbcda3f291")
	key2, _ = crypto.HexToECDSA("8a1f9a8f95be41cd7ccb6168179afb4504aefe388d1e14474d32c45c72ce7b7a")
	key3, _ = crypto.HexToECDSA("49a7b37aa6f6645917e7b807e9d1c00d4fa71f18343b0d4122a4d2df64dd6fee")
	addr1   = crypto.PubkeyToAddress(key1.PublicKey)
	addr2   = crypto.PubkeyToAddress(key2.PublicKey)
	addr3   = crypto.PubkeyToAddress(key3.PublicKey)
	db      = ethdb.NewMemDatabase()
)

// Ensure that key1 has some funds in the genesis block.
gspec := &Genesis{
	Config: &params.ChainConfig{HomesteadBlock: new(big.Int)},
	Alloc:  GenesisAlloc{addr1: {Balance: big.NewInt(1000000)}},
}
genesis := gspec.MustCommit(db)

// This call generates a chain of 5 blocks. The function runs for
// each block and adds different features to gen based on the
// block index.
signer := types.HomesteadSigner{}
chain, _ := GenerateChain(gspec.Config, genesis, ethash.NewFaker(), db, 5, func(i int, gen *BlockGen) {
	switch i {
	case 0:
		// In block 1, addr1 sends addr2 some ether.
		tx, _ := types.SignTx(types.NewTransaction(gen.TxNonce(addr1), addr2, big.NewInt(10000), params.TxGas, nil, nil), signer, key1)
		gen.AddTx(tx)
	case 1:
		// In block 2, addr1 sends some more ether to addr2.
		// addr2 passes it on to addr3.
		tx1, _ := types.SignTx(types.NewTransaction(gen.TxNonce(addr1), addr2, big.NewInt(1000), params.TxGas, nil, nil), signer, key1)
		tx2, _ := types.SignTx(types.NewTransaction(gen.TxNonce(addr2), addr3, big.NewInt(1000), params.TxGas, nil, nil), signer, key2)
		gen.AddTx(tx1)
		gen.AddTx(tx2)
	case 2:
		// Block 3 is empty but was mined by addr3.
		gen.SetCoinbase(addr3)
		gen.SetExtra([]byte("yeehaw"))
	case 3:
		// Block 4 includes blocks 2 and 3 as uncle headers (with modified extra data).
		b2 := gen.PrevBlock(1).Header()
		b2.Extra = []byte("foo")
		gen.AddUncle(b2)
		b3 := gen.PrevBlock(2).Header()
		b3.Extra = []byte("foo")
		gen.AddUncle(b3)
	}
})

// Import the chain. This runs all block validation rules.
blockchain, _ := NewBlockChain(db, nil, gspec.Config, ethash.NewFaker(), vm.Config{})
defer blockchain.Stop()

if i, err := blockchain.InsertChain(chain); err != nil {
	fmt.Printf("insert error (block %d): %v\n", chain[i].NumberU64(), err)
	return
}

state, _ := blockchain.State()
fmt.Printf("last block: #%d\n", blockchain.CurrentBlock().Number())
fmt.Println("balance of addr1:", state.GetBalance(addr1))
fmt.Println("balance of addr2:", state.GetBalance(addr2))
fmt.Println("balance of addr3:", state.GetBalance(addr3))

Output:

last block: #5
balance of addr1: 989000
balance of addr2: 10000
balance of addr3: 19687500000000001000

func GenesisBlockForTesting 

func GenesisBlockForTesting(db ethdb.Database, addr common.Address, balance *big.Int) *types.Block

GenesisBlockForTesting creates and writes a block in which addr has the given wei balance.

func GetHashFn 

func GetHashFn(ref *types.Header, chain ChainContext) func(n uint64) common.Hash

GetHashFn returns a GetHashFunc which retrieves header hashes by number

func IntrinsicGas 

func IntrinsicGas(data []byte, contractCreation, homestead bool) (uint64, error)

IntrinsicGas computes the 'intrinsic gas' for a message with the given data.

func NewEVMContext 

func NewEVMContext(msg Message, header *types.Header, chain ChainContext, author *common.Address) vm.Context

NewEVMContext creates a new context for use in the EVM.

func SetReceiptsData 

func SetReceiptsData(config *params.ChainConfig, block *types.Block, receipts types.Receipts) error

SetReceiptsData computes all the non-consensus fields of the receipts

func SetupGenesisBlock 

func SetupGenesisBlock(db ethdb.Database, genesis *Genesis) (*params.ChainConfig, common.Hash, error)

SetupGenesisBlock writes or updates the genesis block in db. The block that will be used is: 

                     genesis == nil       genesis != nil
                  +------------------------------------------
db has no genesis |  main-net default  |  genesis
db has genesis    |  from DB           |  genesis (if compatible)

The stored chain configuration will be updated if it is compatible (i.e. does not specify a fork block below the local head block). In case of a conflict, the error is a *params.ConfigCompatError and the new, unwritten config is returned.

The returned chain configuration is never nil.

func Transfer 

func Transfer(db vm.StateDB, sender, recipient common.Address, amount *big.Int)

Transfer subtracts amount from sender and adds amount to recipient using the given Db

Types

type BadBlockArgs 

type BadBlockArgs struct {
	Hash   common.Hash   `json:"hash"`
	Header *types.Header `json:"header"`
}

BadBlockArgs represents the entries in the list returned when bad blocks are queried.

type BlockChain 

type BlockChain struct {
	// contains filtered or unexported fields
}

BlockChain represents the canonical chain given a database with a genesis block. The Blockchain manages chain imports, reverts, chain reorganisations.

Importing blocks in to the block chain happens according to the set of rules defined by the two stage Validator. Processing of blocks is done using the Processor which processes the included transaction. The validation of the state is done in the second part of the Validator. Failing results in aborting of the import.

The BlockChain also helps in returning blocks from **any** chain included in the database as well as blocks that represents the canonical chain. It's important to note that GetBlock can return any block and does not need to be included in the canonical one where as GetBlockByNumber always represents the canonical chain.

func NewBlockChain 

func NewBlockChain(db ethdb.Database, cacheConfig *CacheConfig, chainConfig *params.ChainConfig, engine consensus.Engine, vmConfig vm.Config) (*BlockChain, error)

NewBlockChain returns a fully initialised block chain using information available in the database. It initialises the default Ethereum Validator and Processor.

func (*BlockChain) BadBlocks 

func (bc *BlockChain) BadBlocks() ([]BadBlockArgs, error)

BadBlocks returns a list of the last 'bad blocks' that the client has seen on the network

func (*BlockChain) Config 

func (bc *BlockChain) Config() *params.ChainConfig

Config retrieves the blockchain's chain configuration.

func (*BlockChain) CurrentBlock 

func (bc *BlockChain) CurrentBlock() *types.Block

CurrentBlock retrieves the current head block of the canonical chain. The block is retrieved from the blockchain's internal cache.

func (*BlockChain) CurrentFastBlock 

func (bc *BlockChain) CurrentFastBlock() *types.Block

CurrentFastBlock retrieves the current fast-sync head block of the canonical chain. The block is retrieved from the blockchain's internal cache.

func (*BlockChain) CurrentHeader 

func (bc *BlockChain) CurrentHeader() *types.Header

CurrentHeader retrieves the current head header of the canonical chain. The header is retrieved from the HeaderChain's internal cache.

func (*BlockChain) Engine 

func (bc *BlockChain) Engine() consensus.Engine

Engine retrieves the blockchain's consensus engine.

func (*BlockChain) Export 

func (bc *BlockChain) Export(w io.Writer) error

Export writes the active chain to the given writer.

func (*BlockChain) ExportN 

func (bc *BlockChain) ExportN(w io.Writer, first uint64, last uint64) error

ExportN writes a subset of the active chain to the given writer.

func (*BlockChain) FastSyncCommitHead 

func (bc *BlockChain) FastSyncCommitHead(hash common.Hash) error

FastSyncCommitHead sets the current head block to the one defined by the hash irrelevant what the chain contents were prior.

func (*BlockChain) GasLimit 

func (bc *BlockChain) GasLimit() uint64

GasLimit returns the gas limit of the current HEAD block.

func (*BlockChain) Genesis 

func (bc *BlockChain) Genesis() *types.Block

Genesis retrieves the chain's genesis block.

func (*BlockChain) GetBlock 

func (bc *BlockChain) GetBlock(hash common.Hash, number uint64) *types.Block

GetBlock retrieves a block from the database by hash and number, caching it if found.

func (*BlockChain) GetBlockByHash 

func (bc *BlockChain) GetBlockByHash(hash common.Hash) *types.Block

GetBlockByHash retrieves a block from the database by hash, caching it if found.

func (*BlockChain) GetBlockByNumber 

func (bc *BlockChain) GetBlockByNumber(number uint64) *types.Block

GetBlockByNumber retrieves a block from the database by number, caching it (associated with its hash) if found.

func (*BlockChain) GetBlockHashesFromHash 

func (bc *BlockChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash

GetBlockHashesFromHash retrieves a number of block hashes starting at a given hash, fetching towards the genesis block.

func (*BlockChain) GetBlocksFromHash 

func (bc *BlockChain) GetBlocksFromHash(hash common.Hash, n int) (blocks []*types.Block)

GetBlocksFromHash returns the block corresponding to hash and up to n-1 ancestors. [deprecated by eth/62]

func (*BlockChain) GetBody 

func (bc *BlockChain) GetBody(hash common.Hash) *types.Body

GetBody retrieves a block body (transactions and uncles) from the database by hash, caching it if found.

func (*BlockChain) GetBodyRLP 

func (bc *BlockChain) GetBodyRLP(hash common.Hash) rlp.RawValue

GetBodyRLP retrieves a block body in RLP encoding from the database by hash, caching it if found.

func (*BlockChain) GetHeader 

func (bc *BlockChain) GetHeader(hash common.Hash, number uint64) *types.Header

GetHeader retrieves a block header from the database by hash and number, caching it if found.

func (*BlockChain) GetHeaderByHash 

func (bc *BlockChain) GetHeaderByHash(hash common.Hash) *types.Header

GetHeaderByHash retrieves a block header from the database by hash, caching it if found.

func (*BlockChain) GetHeaderByNumber 

func (bc *BlockChain) GetHeaderByNumber(number uint64) *types.Header

GetHeaderByNumber retrieves a block header from the database by number, caching it (associated with its hash) if found.

func (*BlockChain) GetReceiptsByHash 

func (bc *BlockChain) GetReceiptsByHash(hash common.Hash) types.Receipts

GetReceiptsByHash retrieves the receipts for all transactions in a given block.

func (*BlockChain) GetTd 

func (bc *BlockChain) GetTd(hash common.Hash, number uint64) *big.Int

GetTd retrieves a block's total difficulty in the canonical chain from the database by hash and number, caching it if found.

func (*BlockChain) GetTdByHash 

func (bc *BlockChain) GetTdByHash(hash common.Hash) *big.Int

GetTdByHash retrieves a block's total difficulty in the canonical chain from the database by hash, caching it if found.

func (*BlockChain) GetUnclesInChain 

func (bc *BlockChain) GetUnclesInChain(block *types.Block, length int) []*types.Header

GetUnclesInChain retrieves all the uncles from a given block backwards until a specific distance is reached.

func (*BlockChain) HasBlock 

func (bc *BlockChain) HasBlock(hash common.Hash, number uint64) bool

HasBlock checks if a block is fully present in the database or not.

func (*BlockChain) HasBlockAndState 

func (bc *BlockChain) HasBlockAndState(hash common.Hash, number uint64) bool

HasBlockAndState checks if a block and associated state trie is fully present in the database or not, caching it if present.

func (*BlockChain) HasHeader 

func (bc *BlockChain) HasHeader(hash common.Hash, number uint64) bool

HasHeader checks if a block header is present in the database or not, caching it if present.

func (*BlockChain) HasState 

func (bc *BlockChain) HasState(hash common.Hash) bool

HasState checks if state trie is fully present in the database or not.

func (*BlockChain) InsertChain 

func (bc *BlockChain) InsertChain(chain types.Blocks) (int, error)

InsertChain attempts to insert the given batch of blocks in to the canonical chain or, otherwise, create a fork. If an error is returned it will return the index number of the failing block as well an error describing what went wrong.

After insertion is done, all accumulated events will be fired.

func (*BlockChain) InsertHeaderChain 

func (bc *BlockChain) InsertHeaderChain(chain []*types.Header, checkFreq int) (int, error)

InsertHeaderChain attempts to insert the given header chain in to the local chain, possibly creating a reorg. If an error is returned, it will return the index number of the failing header as well an error describing what went wrong.

The verify parameter can be used to fine tune whether nonce verification should be done or not. The reason behind the optional check is because some of the header retrieval mechanisms already need to verify nonces, as well as because nonces can be verified sparsely, not needing to check each.

func (*BlockChain) InsertReceiptChain 

func (bc *BlockChain) InsertReceiptChain(blockChain types.Blocks, receiptChain []types.Receipts) (int, error)

InsertReceiptChain attempts to complete an already existing header chain with transaction and receipt data.

func (*BlockChain) PostChainEvents 

func (bc *BlockChain) PostChainEvents(events []interface{}, logs []*types.Log)

PostChainEvents iterates over the events generated by a chain insertion and posts them into the event feed. TODO: Should not expose PostChainEvents. The chain events should be posted in WriteBlock.

func (*BlockChain) Processor 

func (bc *BlockChain) Processor() Processor

Processor returns the current processor.

func (*BlockChain) Reset 

func (bc *BlockChain) Reset() error

Reset purges the entire blockchain, restoring it to its genesis state.

func (*BlockChain) ResetWithGenesisBlock 

func (bc *BlockChain) ResetWithGenesisBlock(genesis *types.Block) error

ResetWithGenesisBlock purges the entire blockchain, restoring it to the specified genesis state.

func (*BlockChain) Rollback 

func (bc *BlockChain) Rollback(chain []common.Hash)

Rollback is designed to remove a chain of links from the database that aren't certain enough to be valid.

func (*BlockChain) SetHead 

func (bc *BlockChain) SetHead(head uint64) error

SetHead rewinds the local chain to a new head. In the case of headers, everything above the new head will be deleted and the new one set. In the case of blocks though, the head may be further rewound if block bodies are missing (non-archive nodes after a fast sync).

func (*BlockChain) SetProcessor 

func (bc *BlockChain) SetProcessor(processor Processor)

SetProcessor sets the processor required for making state modifications.

func (*BlockChain) SetValidator 

func (bc *BlockChain) SetValidator(validator Validator)

SetValidator sets the validator which is used to validate incoming blocks.

func (*BlockChain) State 

func (bc *BlockChain) State() (*state.StateDB, error)

State returns a new mutable state based on the current HEAD block.

func (*BlockChain) StateAt 

func (bc *BlockChain) StateAt(root common.Hash) (*state.StateDB, error)

StateAt returns a new mutable state based on a particular point in time.

func (*BlockChain) Stop 

func (bc *BlockChain) Stop()

Stop stops the blockchain service. If any imports are currently in progress it will abort them using the procInterrupt.

func (*BlockChain) SubscribeChainEvent 

func (bc *BlockChain) SubscribeChainEvent(ch chan<- ChainEvent) event.Subscription

SubscribeChainEvent registers a subscription of ChainEvent.

func (*BlockChain) SubscribeChainHeadEvent 

func (bc *BlockChain) SubscribeChainHeadEvent(ch chan<- ChainHeadEvent) event.Subscription

SubscribeChainHeadEvent registers a subscription of ChainHeadEvent.

func (*BlockChain) SubscribeChainSideEvent 

func (bc *BlockChain) SubscribeChainSideEvent(ch chan<- ChainSideEvent) event.Subscription

SubscribeChainSideEvent registers a subscription of ChainSideEvent.

func (*BlockChain) SubscribeLogsEvent 

func (bc *BlockChain) SubscribeLogsEvent(ch chan<- []*types.Log) event.Subscription

SubscribeLogsEvent registers a subscription of []*types.Log.

func (*BlockChain) SubscribeRemovedLogsEvent 

func (bc *BlockChain) SubscribeRemovedLogsEvent(ch chan<- RemovedLogsEvent) event.Subscription

SubscribeRemovedLogsEvent registers a subscription of RemovedLogsEvent.

func (*BlockChain) TrieNode 

func (bc *BlockChain) TrieNode(hash common.Hash) ([]byte, error)

TrieNode retrieves a blob of data associated with a trie node (or code hash) either from ephemeral in-memory cache, or from persistent storage.

func (*BlockChain) Validator 

func (bc *BlockChain) Validator() Validator

Validator returns the current validator.

func (*BlockChain) WriteBlockWithState 

func (bc *BlockChain) WriteBlockWithState(block *types.Block, receipts []*types.Receipt, state *state.StateDB) (status WriteStatus, err error)

WriteBlockWithState writes the block and all associated state to the database.

func (*BlockChain) WriteBlockWithoutState 

func (bc *BlockChain) WriteBlockWithoutState(block *types.Block, td *big.Int) (err error)

WriteBlockWithoutState writes only the block and its metadata to the database, but does not write any state. This is used to construct competing side forks up to the point where they exceed the canonical total difficulty.

type BlockGen 

type BlockGen struct {
	// contains filtered or unexported fields
}

BlockGen creates blocks for testing. See GenerateChain for a detailed explanation.

func (*BlockGen) AddTx 

func (b *BlockGen) AddTx(tx *types.Transaction)

AddTx adds a transaction to the generated block. If no coinbase has been set, the block's coinbase is set to the zero address.

AddTx panics if the transaction cannot be executed. In addition to the protocol-imposed limitations (gas limit, etc.), there are some further limitations on the content of transactions that can be added. Notably, contract code relying on the BLOCKHASH instruction will panic during execution.

func (*BlockGen) AddTxWithChain 

func (b *BlockGen) AddTxWithChain(bc *BlockChain, tx *types.Transaction)

AddTxWithChain adds a transaction to the generated block. If no coinbase has been set, the block's coinbase is set to the zero address.

AddTxWithChain panics if the transaction cannot be executed. In addition to the protocol-imposed limitations (gas limit, etc.), there are some further limitations on the content of transactions that can be added. If contract code relies on the BLOCKHASH instruction, the block in chain will be returned.

func (*BlockGen) AddUncheckedReceipt 

func (b *BlockGen) AddUncheckedReceipt(receipt *types.Receipt)

AddUncheckedReceipt forcefully adds a receipts to the block without a backing transaction.

AddUncheckedReceipt will cause consensus failures when used during real chain processing. This is best used in conjunction with raw block insertion.

func (*BlockGen) AddUncle 

func (b *BlockGen) AddUncle(h *types.Header)

AddUncle adds an uncle header to the generated block.

func (*BlockGen) Number 

func (b *BlockGen) Number() *big.Int

Number returns the block number of the block being generated.

func (*BlockGen) OffsetTime 

func (b *BlockGen) OffsetTime(seconds int64)

OffsetTime modifies the time instance of a block, implicitly changing its associated difficulty. It's useful to test scenarios where forking is not tied to chain length directly.

func (*BlockGen) PrevBlock 

func (b *BlockGen) PrevBlock(index int) *types.Block

PrevBlock returns a previously generated block by number. It panics if num is greater or equal to the number of the block being generated. For index -1, PrevBlock returns the parent block given to GenerateChain.

func (*BlockGen) SetCoinbase 

func (b *BlockGen) SetCoinbase(addr common.Address)

SetCoinbase sets the coinbase of the generated block. It can be called at most once.

func (*BlockGen) SetExtra 

func (b *BlockGen) SetExtra(data []byte)

SetExtra sets the extra data field of the generated block.

func (*BlockGen) TxNonce 

func (b *BlockGen) TxNonce(addr common.Address) uint64

TxNonce returns the next valid transaction nonce for the account at addr. It panics if the account does not exist.

type BlockValidator 

type BlockValidator struct {
	// contains filtered or unexported fields
}

BlockValidator is responsible for validating block headers, uncles and processed state.

BlockValidator implements Validator.

func NewBlockValidator 

func NewBlockValidator(config *params.ChainConfig, blockchain *BlockChain, engine consensus.Engine) *BlockValidator

NewBlockValidator returns a new block validator which is safe for re-use

func (*BlockValidator) ValidateBody 

func (v *BlockValidator) ValidateBody(block *types.Block) error

ValidateBody validates the given block's uncles and verifies the the block header's transaction and uncle roots. The headers are assumed to be already validated at this point.

func (*BlockValidator) ValidateState 

func (v *BlockValidator) ValidateState(block, parent *types.Block, statedb *state.StateDB, receipts types.Receipts, usedGas uint64) error

ValidateState validates the various changes that happen after a state transition, such as amount of used gas, the receipt roots and the state root itself. ValidateState returns a database batch if the validation was a success otherwise nil and an error is returned.

type CacheConfig 

type CacheConfig struct {
	Disabled      bool          // Whether to disable trie write caching (archive node)
	TrieNodeLimit int           // Memory limit (MB) at which to flush the current in-memory trie to disk
	TrieTimeLimit time.Duration // Time limit after which to flush the current in-memory trie to disk
}

CacheConfig contains the configuration values for the trie caching/pruning that's resident in a blockchain.

type ChainContext 

type ChainContext interface {
	// Engine retrieves the chain's consensus engine.
	Engine() consensus.Engine

	// GetHeader returns the hash corresponding to their hash.
	GetHeader(common.Hash, uint64) *types.Header
}

ChainContext supports retrieving headers and consensus parameters from the current blockchain to be used during transaction processing.

type ChainEvent 

type ChainEvent struct {
	Block *types.Block
	Hash  common.Hash
	Logs  []*types.Log
}

type ChainHeadEvent 

type ChainHeadEvent struct{ Block *types.Block }

type ChainIndexer 

type ChainIndexer struct {
	// contains filtered or unexported fields
}

ChainIndexer does a post-processing job for equally sized sections of the canonical chain (like BlooomBits and CHT structures). A ChainIndexer is connected to the blockchain through the event system by starting a ChainEventLoop in a goroutine.

Further child ChainIndexers can be added which use the output of the parent section indexer. These child indexers receive new head notifications only after an entire section has been finished or in case of rollbacks that might affect already finished sections.

func NewChainIndexer 

func NewChainIndexer(chainDb, indexDb ethdb.Database, backend ChainIndexerBackend, section, confirm uint64, throttling time.Duration, kind string) *ChainIndexer

NewChainIndexer creates a new chain indexer to do background processing on chain segments of a given size after certain number of confirmations passed. The throttling parameter might be used to prevent database thrashing.

func (*ChainIndexer) AddChildIndexer 

func (c *ChainIndexer) AddChildIndexer(indexer *ChainIndexer)

AddChildIndexer adds a child ChainIndexer that can use the output of this one

func (*ChainIndexer) AddKnownSectionHead 

func (c *ChainIndexer) AddKnownSectionHead(section uint64, shead common.Hash)

AddKnownSectionHead marks a new section head as known/processed if it is newer than the already known best section head

func (*ChainIndexer) Close 

func (c *ChainIndexer) Close() error

Close tears down all goroutines belonging to the indexer and returns any error that might have occurred internally.

func (*ChainIndexer) SectionHead 

func (c *ChainIndexer) SectionHead(section uint64) common.Hash

SectionHead retrieves the last block hash of a processed section from the index database.

func (*ChainIndexer) Sections 

func (c *ChainIndexer) Sections() (uint64, uint64, common.Hash)

Sections returns the number of processed sections maintained by the indexer and also the information about the last header indexed for potential canonical verifications.

func (*ChainIndexer) Start 

func (c *ChainIndexer) Start(chain ChainIndexerChain)

Start creates a goroutine to feed chain head events into the indexer for cascading background processing. Children do not need to be started, they are notified about new events by their parents.

type ChainIndexerBackend 

type ChainIndexerBackend interface {
	// Reset initiates the processing of a new chain segment, potentially terminating
	// any partially completed operations (in case of a reorg).
	Reset(section uint64, prevHead common.Hash) error

	// Process crunches through the next header in the chain segment. The caller
	// will ensure a sequential order of headers.
	Process(header *types.Header)

	// Commit finalizes the section metadata and stores it into the database.
	Commit() error
}

ChainIndexerBackend defines the methods needed to process chain segments in the background and write the segment results into the database. These can be used to create filter blooms or CHTs.

type ChainIndexerChain 

type ChainIndexerChain interface {
	// CurrentHeader retrieves the latest locally known header.
	CurrentHeader() *types.Header

	// SubscribeChainEvent subscribes to new head header notifications.
	SubscribeChainEvent(ch chan<- ChainEvent) event.Subscription
}

ChainIndexerChain interface is used for connecting the indexer to a blockchain

type ChainSideEvent 

type ChainSideEvent struct {
	Block *types.Block
}

type DeleteCallback 

type DeleteCallback func(common.Hash, uint64)

DeleteCallback is a callback function that is called by SetHead before each header is deleted.

type GasPool 

type GasPool uint64

GasPool tracks the amount of gas available during execution of the transactions in a block. The zero value is a pool with zero gas available.

func (*GasPool) AddGas 

func (gp *GasPool) AddGas(amount uint64) *GasPool

AddGas makes gas available for execution.

func (*GasPool) Gas 

func (gp *GasPool) Gas() uint64

Gas returns the amount of gas remaining in the pool.

func (*GasPool) String 

func (gp *GasPool) String() string

func (*GasPool) SubGas 

func (gp *GasPool) SubGas(amount uint64) error

SubGas deducts the given amount from the pool if enough gas is available and returns an error otherwise.

type Genesis 

type Genesis struct {
	Config     *params.ChainConfig `json:"config"`
	Nonce      uint64              `json:"nonce"`
	Timestamp  uint64              `json:"timestamp"`
	ExtraData  []byte              `json:"extraData"`
	GasLimit   uint64              `json:"gasLimit"   gencodec:"required"`
	Difficulty *big.Int            `json:"difficulty" gencodec:"required"`
	Mixhash    common.Hash         `json:"mixHash"`
	Coinbase   common.Address      `json:"coinbase"`
	Alloc      GenesisAlloc        `json:"alloc"      gencodec:"required"`

	// These fields are used for consensus tests. Please don't use them
	// in actual genesis blocks.
	Number     uint64      `json:"number"`
	GasUsed    uint64      `json:"gasUsed"`
	ParentHash common.Hash `json:"parentHash"`
}

Genesis specifies the header fields, state of a genesis block. It also defines hard fork switch-over blocks through the chain configuration.

func DefaultGenesisBlock 

func DefaultGenesisBlock() *Genesis

DefaultGenesisBlock returns the Ethereum main net genesis block.

func DefaultRinkebyGenesisBlock 

func DefaultRinkebyGenesisBlock() *Genesis

DefaultRinkebyGenesisBlock returns the Rinkeby network genesis block.

func DefaultTestnetGenesisBlock 

func DefaultTestnetGenesisBlock() *Genesis

DefaultTestnetGenesisBlock returns the Ropsten network genesis block.

func DeveloperGenesisBlock 

func DeveloperGenesisBlock(period uint64, faucet common.Address) *Genesis

DeveloperGenesisBlock returns the 'geth --dev' genesis block. Note, this must be seeded with the

func (*Genesis) Commit 

func (g *Genesis) Commit(db ethdb.Database) (*types.Block, error)

Commit writes the block and state of a genesis specification to the database. The block is committed as the canonical head block.

func (Genesis) MarshalJSON 

func (g Genesis) MarshalJSON() ([]byte, error)

func (*Genesis) MustCommit 

func (g *Genesis) MustCommit(db ethdb.Database) *types.Block

MustCommit writes the genesis block and state to db, panicking on error. The block is committed as the canonical head block.

func (*Genesis) ToBlock 

func (g *Genesis) ToBlock(db ethdb.Database) *types.Block

ToBlock creates the genesis block and writes state of a genesis specification to the given database (or discards it if nil).

func (*Genesis) UnmarshalJSON 

func (g *Genesis) UnmarshalJSON(input []byte) error

type GenesisAccount 

type GenesisAccount struct {
	Code       []byte                      `json:"code,omitempty"`
	Storage    map[common.Hash]common.Hash `json:"storage,omitempty"`
	Balance    *big.Int                    `json:"balance" gencodec:"required"`
	Nonce      uint64                      `json:"nonce,omitempty"`
	PrivateKey []byte                      `json:"secretKey,omitempty"` // for tests
}

GenesisAccount is an account in the state of the genesis block.

func (GenesisAccount) MarshalJSON 

func (g GenesisAccount) MarshalJSON() ([]byte, error)

func (*GenesisAccount) UnmarshalJSON 

func (g *GenesisAccount) UnmarshalJSON(input []byte) error

type GenesisAlloc 

type GenesisAlloc map[common.Address]GenesisAccount

GenesisAlloc specifies the initial state that is part of the genesis block.

func (*GenesisAlloc) UnmarshalJSON 

func (ga *GenesisAlloc) UnmarshalJSON(data []byte) error

type GenesisMismatchError 

type GenesisMismatchError struct {
	Stored, New common.Hash
}

GenesisMismatchError is raised when trying to overwrite an existing genesis block with an incompatible one.

func (*GenesisMismatchError) Error 

func (e *GenesisMismatchError) Error() string

type HeaderChain 

type HeaderChain struct {
	// contains filtered or unexported fields
}

HeaderChain implements the basic block header chain logic that is shared by core.BlockChain and light.LightChain. It is not usable in itself, only as a part of either structure. It is not thread safe either, the encapsulating chain structures should do the necessary mutex locking/unlocking.

func NewHeaderChain 

func NewHeaderChain(chainDb ethdb.Database, config *params.ChainConfig, engine consensus.Engine, procInterrupt func() bool) (*HeaderChain, error)

NewHeaderChain creates a new HeaderChain structure. 

getValidator should return the parent's validator
procInterrupt points to the parent's interrupt semaphore
wg points to the parent's shutdown wait group

func (*HeaderChain) Config 

func (hc *HeaderChain) Config() *params.ChainConfig

Config retrieves the header chain's chain configuration.

func (*HeaderChain) CurrentHeader 

func (hc *HeaderChain) CurrentHeader() *types.Header

CurrentHeader retrieves the current head header of the canonical chain. The header is retrieved from the HeaderChain's internal cache.

func (*HeaderChain) Engine 

func (hc *HeaderChain) Engine() consensus.Engine

Engine retrieves the header chain's consensus engine.

func (*HeaderChain) GetBlock 

func (hc *HeaderChain) GetBlock(hash common.Hash, number uint64) *types.Block

GetBlock implements consensus.ChainReader, and returns nil for every input as a header chain does not have blocks available for retrieval.

func (*HeaderChain) GetBlockHashesFromHash 

func (hc *HeaderChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash

GetBlockHashesFromHash retrieves a number of block hashes starting at a given hash, fetching towards the genesis block.

func (*HeaderChain) GetBlockNumber 

func (hc *HeaderChain) GetBlockNumber(hash common.Hash) *uint64

GetBlockNumber retrieves the block number belonging to the given hash from the cache or database

func (*HeaderChain) GetHeader 

func (hc *HeaderChain) GetHeader(hash common.Hash, number uint64) *types.Header

GetHeader retrieves a block header from the database by hash and number, caching it if found.

func (*HeaderChain) GetHeaderByHash 

func (hc *HeaderChain) GetHeaderByHash(hash common.Hash) *types.Header

GetHeaderByHash retrieves a block header from the database by hash, caching it if found.

func (*HeaderChain) GetHeaderByNumber 

func (hc *HeaderChain) GetHeaderByNumber(number uint64) *types.Header

GetHeaderByNumber retrieves a block header from the database by number, caching it (associated with its hash) if found.

func (*HeaderChain) GetTd 

func (hc *HeaderChain) GetTd(hash common.Hash, number uint64) *big.Int

GetTd retrieves a block's total difficulty in the canonical chain from the database by hash and number, caching it if found.

func (*HeaderChain) GetTdByHash 

func (hc *HeaderChain) GetTdByHash(hash common.Hash) *big.Int

GetTdByHash retrieves a block's total difficulty in the canonical chain from the database by hash, caching it if found.

func (*HeaderChain) HasHeader 

func (hc *HeaderChain) HasHeader(hash common.Hash, number uint64) bool

HasHeader checks if a block header is present in the database or not.

func (*HeaderChain) InsertHeaderChain 

func (hc *HeaderChain) InsertHeaderChain(chain []*types.Header, writeHeader WhCallback, start time.Time) (int, error)

InsertHeaderChain attempts to insert the given header chain in to the local chain, possibly creating a reorg. If an error is returned, it will return the index number of the failing header as well an error describing what went wrong.

The verify parameter can be used to fine tune whether nonce verification should be done or not. The reason behind the optional check is because some of the header retrieval mechanisms already need to verfy nonces, as well as because nonces can be verified sparsely, not needing to check each.

func (*HeaderChain) SetCurrentHeader 

func (hc *HeaderChain) SetCurrentHeader(head *types.Header)

SetCurrentHeader sets the current head header of the canonical chain.

func (*HeaderChain) SetGenesis 

func (hc *HeaderChain) SetGenesis(head *types.Header)

SetGenesis sets a new genesis block header for the chain

func (*HeaderChain) SetHead 

func (hc *HeaderChain) SetHead(head uint64, delFn DeleteCallback)

SetHead rewinds the local chain to a new head. Everything above the new head will be deleted and the new one set.

func (*HeaderChain) ValidateHeaderChain 

func (hc *HeaderChain) ValidateHeaderChain(chain []*types.Header, checkFreq int) (int, error)

func (*HeaderChain) WriteHeader 

func (hc *HeaderChain) WriteHeader(header *types.Header) (status WriteStatus, err error)

WriteHeader writes a header into the local chain, given that its parent is already known. If the total difficulty of the newly inserted header becomes greater than the current known TD, the canonical chain is re-routed.

Note: This method is not concurrent-safe with inserting blocks simultaneously into the chain, as side effects caused by reorganisations cannot be emulated without the real blocks. Hence, writing headers directly should only be done in two scenarios: pure-header mode of operation (light clients), or properly separated header/block phases (non-archive clients).

func (*HeaderChain) WriteTd 

func (hc *HeaderChain) WriteTd(hash common.Hash, number uint64, td *big.Int) error

WriteTd stores a block's total difficulty into the database, also caching it along the way.

type Message 

type Message interface {
	From() common.Address
	//FromFrontier() (common.Address, error)
	To() *common.Address

	GasPrice() *big.Int
	Gas() uint64
	Value() *big.Int

	Nonce() uint64
	CheckNonce() bool
	Data() []byte
}

Message represents a message sent to a contract.

type NewMinedBlockEvent 

type NewMinedBlockEvent struct{ Block *types.Block }

NewMinedBlockEvent is posted when a block has been imported.

type NewTxsEvent 

type NewTxsEvent struct{ Txs []*types.Transaction }

NewTxsEvent is posted when a batch of transactions enter the transaction pool.

type PendingLogsEvent 

type PendingLogsEvent struct {
	Logs []*types.Log
}

PendingLogsEvent is posted pre mining and notifies of pending logs.

type PendingStateEvent 

type PendingStateEvent struct{}

PendingStateEvent is posted pre mining and notifies of pending state changes.

type Processor 

type Processor interface {
	Process(block *types.Block, statedb *state.StateDB, cfg vm.Config) (types.Receipts, []*types.Log, uint64, error)
}

Processor is an interface for processing blocks using a given initial state.

Process takes the block to be processed and the statedb upon which the initial state is based. It should return the receipts generated, amount of gas used in the process and return an error if any of the internal rules failed.

type RemovedLogsEvent 

type RemovedLogsEvent struct{ Logs []*types.Log }

RemovedLogsEvent is posted when a reorg happens

type StateProcessor 

type StateProcessor struct {
	// contains filtered or unexported fields
}

StateProcessor is a basic Processor, which takes care of transitioning state from one point to another.

StateProcessor implements Processor.

func NewStateProcessor 

func NewStateProcessor(config *params.ChainConfig, bc *BlockChain, engine consensus.Engine) *StateProcessor

NewStateProcessor initialises a new StateProcessor.

func (*StateProcessor) Process 

func (p *StateProcessor) Process(block *types.Block, statedb *state.StateDB, cfg vm.Config) (types.Receipts, []*types.Log, uint64, error)

Process processes the state changes according to the Ethereum rules by running the transaction messages using the statedb and applying any rewards to both the processor (coinbase) and any included uncles.

Process returns the receipts and logs accumulated during the process and returns the amount of gas that was used in the process. If any of the transactions failed to execute due to insufficient gas it will return an error.

type StateTransition 

type StateTransition struct {
	// contains filtered or unexported fields
}

The State Transitioning Model

A state transition is a change made when a transaction is applied to the current world state The state transitioning model does all all the necessary work to work out a valid new state root.

1) Nonce handling 2) Pre pay gas 3) Create a new state object if the recipient is \0*32 4) Value transfer == If contract creation == 

4a) Attempt to run transaction data
4b) If valid, use result as code for the new state object

== end == 5) Run Script section 6) Derive new state root

func NewStateTransition 

func NewStateTransition(evm *vm.EVM, msg Message, gp *GasPool) *StateTransition

NewStateTransition initialises and returns a new state transition object.

func (*StateTransition) TransitionDb 

func (st *StateTransition) TransitionDb() (ret []byte, usedGas uint64, failed bool, err error)

TransitionDb will transition the state by applying the current message and returning the result including the the used gas. It returns an error if it failed. An error indicates a consensus issue.

type TxPool 

type TxPool struct {
	// contains filtered or unexported fields
}

TxPool contains all currently known transactions. Transactions enter the pool when they are received from the network or submitted locally. They exit the pool when they are included in the blockchain.

The pool separates processable transactions (which can be applied to the current state) and future transactions. Transactions move between those two states over time as they are received and processed.

func NewTxPool 

func NewTxPool(config TxPoolConfig, chainconfig *params.ChainConfig, chain blockChain) *TxPool

NewTxPool creates a new transaction pool to gather, sort and filter inbound transactions from the network.

func (*TxPool) AddLocal 

func (pool *TxPool) AddLocal(tx *types.Transaction) error

AddLocal enqueues a single transaction into the pool if it is valid, marking the sender as a local one in the mean time, ensuring it goes around the local pricing constraints.

func (*TxPool) AddLocals 

func (pool *TxPool) AddLocals(txs []*types.Transaction) []error

AddLocals enqueues a batch of transactions into the pool if they are valid, marking the senders as a local ones in the mean time, ensuring they go around the local pricing constraints.

func (*TxPool) AddRemote 

func (pool *TxPool) AddRemote(tx *types.Transaction) error

AddRemote enqueues a single transaction into the pool if it is valid. If the sender is not among the locally tracked ones, full pricing constraints will apply.

func (*TxPool) AddRemotes 

func (pool *TxPool) AddRemotes(txs []*types.Transaction) []error

AddRemotes enqueues a batch of transactions into the pool if they are valid. If the senders are not among the locally tracked ones, full pricing constraints will apply.

func (*TxPool) Content 

func (pool *TxPool) Content() (map[common.Address]types.Transactions, map[common.Address]types.Transactions)

Content retrieves the data content of the transaction pool, returning all the pending as well as queued transactions, grouped by account and sorted by nonce.

func (*TxPool) GasPrice 

func (pool *TxPool) GasPrice() *big.Int

GasPrice returns the current gas price enforced by the transaction pool.

func (*TxPool) Get 

func (pool *TxPool) Get(hash common.Hash) *types.Transaction

Get returns a transaction if it is contained in the pool and nil otherwise.

func (*TxPool) Pending 

func (pool *TxPool) Pending() (map[common.Address]types.Transactions, error)

Pending retrieves all currently processable transactions, groupped by origin account and sorted by nonce. The returned transaction set is a copy and can be freely modified by calling code.

func (*TxPool) SetGasPrice 

func (pool *TxPool) SetGasPrice(price *big.Int)

SetGasPrice updates the minimum price required by the transaction pool for a new transaction, and drops all transactions below this threshold.

func (*TxPool) State 

func (pool *TxPool) State() *state.ManagedState

State returns the virtual managed state of the transaction pool.

func (*TxPool) Stats 

func (pool *TxPool) Stats() (int, int)

Stats retrieves the current pool stats, namely the number of pending and the number of queued (non-executable) transactions.

func (*TxPool) Status 

func (pool *TxPool) Status(hashes []common.Hash) []TxStatus

Status returns the status (unknown/pending/queued) of a batch of transactions identified by their hashes.

func (*TxPool) Stop 

func (pool *TxPool) Stop()

Stop terminates the transaction pool.

func (*TxPool) SubscribeNewTxsEvent 

func (pool *TxPool) SubscribeNewTxsEvent(ch chan<- NewTxsEvent) event.Subscription

SubscribeNewTxsEvent registers a subscription of NewTxsEvent and starts sending event to the given channel.

type TxPoolConfig 

type TxPoolConfig struct {
	NoLocals  bool          // Whether local transaction handling should be disabled
	Journal   string        // Journal of local transactions to survive node restarts
	Rejournal time.Duration // Time interval to regenerate the local transaction journal

	PriceLimit uint64 // Minimum gas price to enforce for acceptance into the pool
	PriceBump  uint64 // Minimum price bump percentage to replace an already existing transaction (nonce)

	AccountSlots uint64 // Minimum number of executable transaction slots guaranteed per account
	GlobalSlots  uint64 // Maximum number of executable transaction slots for all accounts
	AccountQueue uint64 // Maximum number of non-executable transaction slots permitted per account
	GlobalQueue  uint64 // Maximum number of non-executable transaction slots for all accounts

	Lifetime time.Duration // Maximum amount of time non-executable transaction are queued
}

TxPoolConfig are the configuration parameters of the transaction pool.

type TxStatus 

type TxStatus uint

TxStatus is the current status of a transaction as seen by the pool. 

const (
	TxStatusUnknown TxStatus = iota
	TxStatusQueued
	TxStatusPending
	TxStatusIncluded
)

type Validator 

type Validator interface {
	// ValidateBody validates the given block's content.
	ValidateBody(block *types.Block) error

	// ValidateState validates the given statedb and optionally the receipts and
	// gas used.
	ValidateState(block, parent *types.Block, state *state.StateDB, receipts types.Receipts, usedGas uint64) error
}

Validator is an interface which defines the standard for block validation. It is only responsible for validating block contents, as the header validation is done by the specific consensus engines.

type WhCallback 

type WhCallback func(*types.Header) error

WhCallback is a callback function for inserting individual headers. A callback is used for two reasons: first, in a LightChain, status should be processed and light chain events sent, while in a BlockChain this is not necessary since chain events are sent after inserting blocks. Second, the header writes should be protected by the parent chain mutex individually.

type WriteStatus 

type WriteStatus byte

WriteStatus status of write 

const (
	NonStatTy WriteStatus = iota
	CanonStatTy
	SideStatTy
)

Source Files

View all Source files

Directories

Path Synopsis
Provides support for dealing with EVM assembly instructions (e.g., disassembling them).
 Provides support for dealing with EVM assembly instructions (e.g., disassembling them).
Package bloombits implements bloom filtering on batches of data.
 Package bloombits implements bloom filtering on batches of data.
Package rawdb contains a collection of low level database accessors.
 Package rawdb contains a collection of low level database accessors.
Package state provides a caching layer atop the Ethereum state trie.
 Package state provides a caching layer atop the Ethereum state trie.
Package types contains data types related to Ethereum consensus.
 Package types contains data types related to Ethereum consensus.
vm
Package vm implements the Ethereum Virtual Machine.
 Package vm implements the Ethereum Virtual Machine.
runtime
Package runtime provides a basic execution model for executing EVM code.
 Package runtime provides a basic execution model for executing EVM code.

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