api.go

// Copyright 2019 The CortexTheseus Authors
// This file is part of the CortexFoundation library.
//
// The CortexFoundation library is free software: you can redistribute it and/or modify
// it under the terms of the GNU Lesser General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// The CortexFoundation library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU Lesser General Public License for more details.
//
// You should have received a copy of the GNU Lesser General Public License
// along with the CortexFoundation library. If not, see <http://www.gnu.org/licenses/>.

package ctxc

import (
	"compress/gzip"
	"context"
	"errors"
	"fmt"
	"io"
	"math"
	"math/big"
	"os"
	//"runtime"
	"strings"
	"time"

	"github.com/CortexFoundation/CortexTheseus/common"
	"github.com/CortexFoundation/CortexTheseus/common/hexutil"
	"github.com/CortexFoundation/CortexTheseus/core"
	"github.com/CortexFoundation/CortexTheseus/core/rawdb"
	"github.com/CortexFoundation/CortexTheseus/core/state"
	"github.com/CortexFoundation/CortexTheseus/core/types"
	"github.com/CortexFoundation/CortexTheseus/core/vm"
	"github.com/CortexFoundation/CortexTheseus/internal/ctxcapi"
	"github.com/CortexFoundation/CortexTheseus/log"
	"github.com/CortexFoundation/CortexTheseus/params"
	"github.com/CortexFoundation/CortexTheseus/rlp"
	"github.com/CortexFoundation/CortexTheseus/rpc"
	"github.com/CortexFoundation/CortexTheseus/trie"
)

// PublicCortexAPI provides an API to access Cortex full node-related
// information.
type PublicCortexAPI struct {
	e *Cortex
}

// NewPublicCortexAPI creates a new Cortex protocol API for full nodes.
func NewPublicCortexAPI(e *Cortex) *PublicCortexAPI {
	return &PublicCortexAPI{e}
}

// Coinbase is the address that mining rewards will be send to
func (api *PublicCortexAPI) Coinbase() (common.Address, error) {
	return api.e.Coinbase()
}

// Hashrate returns the POW hashrate
func (api *PublicCortexAPI) Hashrate() hexutil.Uint64 {
	return hexutil.Uint64(api.e.Miner().HashRate())
}

// ChainId is the EIP-155 replay-protection chain id for the current cortex chain config.
func (api *PublicCortexAPI) ChainId() hexutil.Uint64 {
	chainID := new(big.Int)
	if config := api.e.chainConfig; config.IsEIP155(api.e.blockchain.CurrentBlock().Number()) {
		chainID = config.ChainID
	}
	return (hexutil.Uint64)(chainID.Uint64())
}

// PublicMinerAPI provides an API to control the miner.
// It offers only methods that operate on data that pose no security risk when it is publicly accessible.
type PublicMinerAPI struct {
	e *Cortex
}

// NewPublicMinerAPI create a new PublicMinerAPI instance.
func NewPublicMinerAPI(e *Cortex) *PublicMinerAPI {
	return &PublicMinerAPI{e}
}

// Mining returns an indication if this node is currently mining.
func (api *PublicMinerAPI) Mining() bool {
	return api.e.IsMining()
}

// PrivateMinerAPI provides private RPC methods to control the miner.
// These methods can be abused by external users and must be considered insecure for use by untrusted users.
type PrivateMinerAPI struct {
	e *Cortex
}

// NewPrivateMinerAPI create a new RPC service which controls the miner of this node.
func NewPrivateMinerAPI(e *Cortex) *PrivateMinerAPI {
	return &PrivateMinerAPI{e: e}
}

// Start starts the miner with the given number of threads. If threads is nil,
// the number of workers started is equal to the number of logical CPUs that are
// usable by this process. If mining is already running, this method adjust the
// number of threads allowed to use and updates the minimum price required by the
// transaction pool.
func (api *PrivateMinerAPI) Start(threads *int) error {
	if threads == nil {
		//return api.e.StartMining(runtime.NumCPU())
		//return api.e.StartMining(1)
	}
	//return api.e.StartMining(*threads)
	return api.e.StartMining(1)
}

// Stop terminates the miner, both at the consensus engine level as well as at
// the block creation level.
func (api *PrivateMinerAPI) Stop() {
	api.e.StopMining()
}

// SetExtra sets the extra data string that is included when this miner mines a block.
func (api *PrivateMinerAPI) SetExtra(extra string) (bool, error) {
	if err := api.e.Miner().SetExtra([]byte(extra)); err != nil {
		return false, err
	}
	return true, nil
}

// SetGasPrice sets the minimum accepted gas price for the miner.
func (api *PrivateMinerAPI) SetGasPrice(gasPrice hexutil.Big) bool {
	api.e.lock.Lock()
	api.e.gasPrice = (*big.Int)(&gasPrice)
	api.e.lock.Unlock()

	api.e.txPool.SetGasPrice((*big.Int)(&gasPrice))
	return true
}

// SetGasLimit sets the gaslimit to target towards during mining.
func (api *PrivateMinerAPI) SetGasLimit(gasLimit hexutil.Uint64) bool {
	api.e.Miner().SetGasCeil(uint64(gasLimit))
	return true
}

// SetCoinbase sets the coinbase of the miner
func (api *PrivateMinerAPI) SetCoinbase(coinbase common.Address) bool {
	api.e.SetCoinbase(coinbase)
	return true
}

// SetRecommitInterval updates the interval for miner sealing work recommitting.
func (api *PrivateMinerAPI) SetRecommitInterval(interval int) {
	api.e.Miner().SetRecommitInterval(time.Duration(interval) * time.Millisecond)
}

// GetHashrate returns the current hashrate of the miner.
func (api *PrivateMinerAPI) GetHashrate() uint64 {
	return api.e.miner.HashRate()
}

// PrivateAdminAPI is the collection of Cortex full node-related APIs
// exposed over the private admin endpoint.
type PrivateAdminAPI struct {
	ctxc *Cortex
}

// NewPrivateAdminAPI creates a new API definition for the full node private
// admin methods of the Cortex service.
func NewPrivateAdminAPI(ctxc *Cortex) *PrivateAdminAPI {
	return &PrivateAdminAPI{ctxc: ctxc}
}

// ExportChain exports the current blockchain into a local file.
func (api *PrivateAdminAPI) ExportChain(file string) (bool, error) {
	if _, err := os.Stat(file); err == nil {
		// File already exists. Allowing overwrite could be a DoS vecotor,
		// since the 'file' may point to arbitrary paths on the drive
		return false, errors.New("location would overwrite an existing file")
	}
	// Make sure we can create the file to export into
	out, err := os.OpenFile(file, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, os.ModePerm)
	if err != nil {
		return false, err
	}
	defer out.Close()

	var writer io.Writer = out
	if strings.HasSuffix(file, ".gz") {
		writer = gzip.NewWriter(writer)
		defer writer.(*gzip.Writer).Close()
	}

	// Export the blockchain
	if err := api.ctxc.BlockChain().Export(writer); err != nil {
		return false, err
	}
	return true, nil
}

func hasAllBlocks(chain *core.BlockChain, bs []*types.Block) bool {
	for _, b := range bs {
		if !chain.HasBlock(b.Hash(), b.NumberU64()) {
			return false
		}
	}

	return true
}

// ImportChain imports a blockchain from a local file.
func (api *PrivateAdminAPI) ImportChain(file string) (bool, error) {
	// Make sure the can access the file to import
	in, err := os.Open(file)
	if err != nil {
		return false, err
	}
	defer in.Close()

	var reader io.Reader = in
	if strings.HasSuffix(file, ".gz") {
		if reader, err = gzip.NewReader(reader); err != nil {
			return false, err
		}
	}

	// Run actual the import in pre-configured batches
	stream := rlp.NewStream(reader, 0)

	blocks, index := make([]*types.Block, 0, 2500), 0
	for batch := 0; ; batch++ {
		// Load a batch of blocks from the input file
		for len(blocks) < cap(blocks) {
			block := new(types.Block)
			if err := stream.Decode(block); err == io.EOF {
				break
			} else if err != nil {
				return false, fmt.Errorf("block %d: failed to parse: %v", index, err)
			}
			blocks = append(blocks, block)
			index++
		}
		if len(blocks) == 0 {
			break
		}

		if hasAllBlocks(api.ctxc.BlockChain(), blocks) {
			blocks = blocks[:0]
			continue
		}
		// Import the batch and reset the buffer
		if _, err := api.ctxc.BlockChain().InsertChain(blocks); err != nil {
			return false, fmt.Errorf("batch %d: failed to insert: %v", batch, err)
		}
		blocks = blocks[:0]
	}
	return true, nil
}

// PublicDebugAPI is the collection of Cortex full node APIs exposed
// over the public debugging endpoint.
type PublicDebugAPI struct {
	ctxc *Cortex
}

// NewPublicDebugAPI creates a new API definition for the full node-
// related public debug methods of the Cortex service.
func NewPublicDebugAPI(ctxc *Cortex) *PublicDebugAPI {
	return &PublicDebugAPI{ctxc: ctxc}
}

// DumpBlock retrieves the entire state of the database at a given block.
func (api *PublicDebugAPI) DumpBlock(blockNr rpc.BlockNumber) (state.Dump, error) {
	if blockNr == rpc.PendingBlockNumber {
		// If we're dumping the pending state, we need to request
		// both the pending block as well as the pending state from
		// the miner and operate on those
		_, stateDb := api.ctxc.miner.Pending()
		return stateDb.RawDump(false, false, true), nil
	}
	var block *types.Block
	if blockNr == rpc.LatestBlockNumber {
		block = api.ctxc.blockchain.CurrentBlock()
	} else if blockNr == rpc.FinalizedBlockNumber {
		block = api.ctxc.blockchain.CurrentFinalizedBlock()
	} else if blockNr == rpc.SafeBlockNumber {
		block = api.ctxc.blockchain.CurrentSafeBlock()
	} else {
		block = api.ctxc.blockchain.GetBlockByNumber(uint64(blockNr))
	}
	if block == nil {
		return state.Dump{}, fmt.Errorf("block #%d not found", blockNr)
	}
	stateDb, err := api.ctxc.BlockChain().StateAt(block.Root())
	if err != nil {
		return state.Dump{}, err
	}
	return stateDb.RawDump(false, false, true), nil
}

// PrivateDebugAPI is the collection of Cortex full node APIs exposed over
// the private debugging endpoint.
type PrivateDebugAPI struct {
	config *params.ChainConfig
	ctxc   *Cortex
}

// NewPrivateDebugAPI creates a new API definition for the full node-related
// private debug methods of the Cortex service.
func NewPrivateDebugAPI(config *params.ChainConfig, ctxc *Cortex) *PrivateDebugAPI {
	return &PrivateDebugAPI{config: config, ctxc: ctxc}
}

// Preimage is a debug API function that returns the preimage for a sha3 hash, if known.
func (api *PrivateDebugAPI) Preimage(ctx context.Context, hash common.Hash) (hexutil.Bytes, error) {
	if preimage := rawdb.ReadPreimage(api.ctxc.ChainDb(), hash); preimage != nil {
		return preimage, nil
	}
	return nil, errors.New("unknown preimage")
}

// BadBlockArgs represents the entries in the list returned when bad blocks are queried.
type BadBlockArgs struct {
	Hash  common.Hash            `json:"hash"`
	Block map[string]interface{} `json:"block"`
	RLP   string                 `json:"rlp"`
}

// GetBadBlocks returns a list of the last 'bad blocks' that the client has seen on the network
// and returns them as a JSON list of block-hashes
// GetBadBlocks returns a list of the last 'bad blocks' that the client has seen on the network
// and returns them as a JSON list of block hashes.
func (api *PrivateDebugAPI) GetBadBlocks(ctx context.Context) ([]*BadBlockArgs, error) {
	var (
		err     error
		blocks  = rawdb.ReadAllBadBlocks(api.ctxc.chainDb)
		results = make([]*BadBlockArgs, 0, len(blocks))
	)
	for _, block := range blocks {
		var (
			blockRlp  string
			blockJSON map[string]interface{}
		)
		if rlpBytes, err := rlp.EncodeToBytes(block); err != nil {
			blockRlp = err.Error() // Hacky, but hey, it works
		} else {
			blockRlp = fmt.Sprintf("%#x", rlpBytes)
		}
		if blockJSON, err = ctxcapi.RPCMarshalBlock(block, true, true); err != nil {
			blockJSON = map[string]interface{}{"error": err.Error()}
		}
		results = append(results, &BadBlockArgs{
			Hash:  block.Hash(),
			RLP:   blockRlp,
			Block: blockJSON,
		})
	}
	return results, nil
}

// StorageRangeResult is the result of a debug_storageRangeAt API call.
type StorageRangeResult struct {
	Storage storageMap   `json:"storage"`
	NextKey *common.Hash `json:"nextKey"` // nil if Storage includes the last key in the trie.
}

type storageMap map[common.Hash]storageEntry

type storageEntry struct {
	Key   *common.Hash `json:"key"`
	Value common.Hash  `json:"value"`
}

// StorageRangeAt returns the storage at the given block height and transaction index.
func (api *PrivateDebugAPI) StorageRangeAt(ctx context.Context, blockHash common.Hash, txIndex int, contractAddress common.Address, keyStart hexutil.Bytes, maxResult int) (StorageRangeResult, error) {
	_, _, statedb, err := api.computeTxEnv(blockHash, txIndex, 0)
	if err != nil {
		return StorageRangeResult{}, err
	}
	st := statedb.StorageTrie(contractAddress)
	if st == nil {
		return StorageRangeResult{}, fmt.Errorf("account %x doesn't exist", contractAddress)
	}
	return storageRangeAt(st, keyStart, maxResult)
}

// computeTxEnv returns the execution environment of a certain transaction.
func (api *PrivateDebugAPI) computeTxEnv(blockHash common.Hash, txIndex int, reexec uint64) (core.Message, vm.BlockContext, *state.StateDB, error) {
	// Create the parent state database
	block := api.ctxc.blockchain.GetBlockByHash(blockHash)
	if block == nil {
		return nil, vm.BlockContext{}, nil, fmt.Errorf("block %x not found", blockHash)
	}
	parent := api.ctxc.blockchain.GetBlock(block.ParentHash(), block.NumberU64()-1)
	if parent == nil {
		return nil, vm.BlockContext{}, nil, fmt.Errorf("parent %x not found", block.ParentHash())
	}
	statedb, err := api.computeStateDB(parent, reexec)
	if err != nil {
		return nil, vm.BlockContext{}, nil, err
	}

	if txIndex == 0 && len(block.Transactions()) == 0 {
		return nil, vm.BlockContext{}, statedb, nil
	}

	// Recompute transactions up to the target index.
	signer := types.MakeSigner(api.config, block.Number())

	for idx, tx := range block.Transactions() {
		// Assemble the transaction call message and return if the requested offset
		msg, _ := tx.AsMessage(signer)
		txContext := core.NewCVMTxContext(msg)
		context := core.NewCVMBlockContext(block.Header(), api.ctxc.blockchain, nil)
		if idx == txIndex {
			return msg, context, statedb, nil
		}
		// Not yet the searched for transaction, execute on top of the current state
		vmenv := vm.NewCVM(context, txContext, statedb, api.config, vm.Config{})
		if _, _, _, _, err := core.ApplyMessage(vmenv, msg, new(core.GasPool).AddGas(tx.Gas()), new(core.QuotaPool).AddQuota(math.MaxUint64)); err != nil {
			return nil, vm.BlockContext{}, nil, fmt.Errorf("tx %x failed: %v", tx.Hash(), err)
		}
		// Ensure any modifications are committed to the state
		statedb.Finalise(true)
	}
	return nil, vm.BlockContext{}, nil, fmt.Errorf("tx index %d out of range for block %x", txIndex, blockHash)
}

func storageRangeAt(st state.Trie, start []byte, maxResult int) (StorageRangeResult, error) {
	it := trie.NewIterator(st.NodeIterator(start))
	result := StorageRangeResult{Storage: storageMap{}}
	for i := 0; i < maxResult && it.Next(); i++ {
		_, content, _, err := rlp.Split(it.Value)
		if err != nil {
			return StorageRangeResult{}, err
		}
		e := storageEntry{Value: common.BytesToHash(content)}
		if preimage := st.GetKey(it.Key); preimage != nil {
			preimage := common.BytesToHash(preimage)
			e.Key = &preimage
		}
		result.Storage[common.BytesToHash(it.Key)] = e
	}
	// Add the 'next key' so clients can continue downloading.
	if it.Next() {
		next := common.BytesToHash(it.Key)
		result.NextKey = &next
	}
	return result, nil
}

// GetModifiedAccountsByNumber returns all accounts that have changed between the
// two blocks specified. A change is defined as a difference in nonce, balance,
// code hash, or storage hash.
//
// With one parameter, returns the list of accounts modified in the specified block.
func (api *PrivateDebugAPI) GetModifiedAccountsByNumber(startNum uint64, endNum *uint64) ([]common.Address, error) {
	var startBlock, endBlock *types.Block

	startBlock = api.ctxc.blockchain.GetBlockByNumber(startNum)
	if startBlock == nil {
		return nil, fmt.Errorf("start block %x not found", startNum)
	}

	if endNum == nil {
		endBlock = startBlock
		startBlock = api.ctxc.blockchain.GetBlockByHash(startBlock.ParentHash())
		if startBlock == nil {
			return nil, fmt.Errorf("block %x has no parent", endBlock.Number())
		}
	} else {
		endBlock = api.ctxc.blockchain.GetBlockByNumber(*endNum)
		if endBlock == nil {
			return nil, fmt.Errorf("end block %d not found", *endNum)
		}
	}
	return api.getModifiedAccounts(startBlock, endBlock)
}

// GetModifiedAccountsByHash returns all accounts that have changed between the
// two blocks specified. A change is defined as a difference in nonce, balance,
// code hash, or storage hash.
//
// With one parameter, returns the list of accounts modified in the specified block.
func (api *PrivateDebugAPI) GetModifiedAccountsByHash(startHash common.Hash, endHash *common.Hash) ([]common.Address, error) {
	var startBlock, endBlock *types.Block
	startBlock = api.ctxc.blockchain.GetBlockByHash(startHash)
	if startBlock == nil {
		return nil, fmt.Errorf("start block %x not found", startHash)
	}

	if endHash == nil {
		endBlock = startBlock
		startBlock = api.ctxc.blockchain.GetBlockByHash(startBlock.ParentHash())
		if startBlock == nil {
			return nil, fmt.Errorf("block %x has no parent", endBlock.Number())
		}
	} else {
		endBlock = api.ctxc.blockchain.GetBlockByHash(*endHash)
		if endBlock == nil {
			return nil, fmt.Errorf("end block %x not found", *endHash)
		}
	}
	return api.getModifiedAccounts(startBlock, endBlock)
}

func (api *PrivateDebugAPI) getModifiedAccounts(startBlock, endBlock *types.Block) ([]common.Address, error) {
	if startBlock.Number().Uint64() >= endBlock.Number().Uint64() {
		return nil, fmt.Errorf("start block height (%d) must be less than end block height (%d)", startBlock.Number().Uint64(), endBlock.Number().Uint64())
	}

	oldTrie, err := trie.NewSecure(startBlock.Root(), trie.NewDatabase(api.ctxc.chainDb))
	if err != nil {
		return nil, err
	}
	newTrie, err := trie.NewSecure(endBlock.Root(), trie.NewDatabase(api.ctxc.chainDb))
	if err != nil {
		return nil, err
	}

	diff, _ := trie.NewDifferenceIterator(oldTrie.NodeIterator([]byte{}), newTrie.NodeIterator([]byte{}))
	iter := trie.NewIterator(diff)

	var dirty []common.Address
	for iter.Next() {
		key := newTrie.GetKey(iter.Key)
		if key == nil {
			return nil, fmt.Errorf("no preimage found for hash %x", iter.Key)
		}
		dirty = append(dirty, common.BytesToAddress(key))
	}
	return dirty, nil
}

// attempted to be reexecuted to generate the desired state.
func (api *PrivateDebugAPI) computeStateDB(block *types.Block, reexec uint64) (*state.StateDB, error) {
	// If we have the state fully available, use that
	statedb, err := api.ctxc.blockchain.StateAt(block.Root())
	if err == nil {
		return statedb, nil
	}
	// Otherwise try to reexec blocks until we find a state or reach our limit
	origin := block.NumberU64()
	database := state.NewDatabaseWithConfig(api.ctxc.ChainDb(), &trie.Config{Cache: 16, Preimages: true})

	for i := uint64(0); i < reexec; i++ {
		block = api.ctxc.blockchain.GetBlock(block.ParentHash(), block.NumberU64()-1)
		if block == nil {
			break
		}
		if statedb, err = state.New(block.Root(), database, nil); err == nil {
			break
		}
	}
	if err != nil {
		switch err.(type) {
		case *trie.MissingNodeError:
			return nil, errors.New("required historical state unavailable")
		default:
			return nil, err
		}
	}
	// State was available at historical point, regenerate
	var (
		start  = time.Now()
		logged time.Time
		proot  common.Hash
	)
	for block.NumberU64() < origin {
		// Print progress logs if long enough time elapsed
		if time.Since(logged) > 8*time.Second {
			log.Info("Regenerating historical state", "block", block.NumberU64()+1, "target", origin, "elapsed", time.Since(start))
			logged = time.Now()
		}
		// Retrieve the next block to regenerate and process it
		if block = api.ctxc.blockchain.GetBlockByNumber(block.NumberU64() + 1); block == nil {
			return nil, fmt.Errorf("block #%d not found", block.NumberU64()+1)
		}
		_, _, _, err := api.ctxc.blockchain.Processor().Process(block, statedb, vm.Config{})
		if err != nil {
			return nil, err
		}
		// Finalize the state so any modifications are written to the trie
		root, err := statedb.Commit(api.ctxc.blockchain.Config().IsEIP158(block.Number()))
		if err != nil {
			return nil, fmt.Errorf("stateAtBlock commit failed, number %d root %v: %w",
				block.NumberU64(), block.Root().Hex(), err)
		}
		statedb, err = state.New(root, database, nil)
		if err != nil {
			return nil, fmt.Errorf("state reset after block %d failed: %v", block.NumberU64(), err)
		}
		database.TrieDB().Reference(root, common.Hash{})
		if proot != (common.Hash{}) {
			database.TrieDB().Dereference(proot)
		}
		proot = root
	}
	nodes, imgs := database.TrieDB().Size()
	log.Info("Historical state regenerated", "block", block.NumberU64(), "elapsed", time.Since(start), "nodes", nodes, "preimages", imgs)
	return statedb, nil
}