Merge branch 'xcthulhu-publictests' into poc-9

5 files changed, 378 insertions, 9 deletions

diff --git a/core/block_processor.go b/core/block_processor.go
index 1a4501740..8974cd94b 100644
--- a/core/block_processor.go
+++ b/core/block_processor.go
@@ -12,7 +12,6 @@ import (
 	"github.com/ethereum/go-ethereum/event"
 	"github.com/ethereum/go-ethereum/logger"
 	"github.com/ethereum/go-ethereum/pow"
-	"github.com/ethereum/go-ethereum/pow/ezp"
 	"github.com/ethereum/go-ethereum/state"
 	"gopkg.in/fatih/set.v0"
 )
@@ -46,11 +45,11 @@ type BlockProcessor struct {
 	eventMux *event.TypeMux
 }
 
-func NewBlockProcessor(db ethutil.Database, txpool *TxPool, chainManager *ChainManager, eventMux *event.TypeMux) *BlockProcessor {
+func NewBlockProcessor(db ethutil.Database, pow pow.PoW, txpool *TxPool, chainManager *ChainManager, eventMux *event.TypeMux) *BlockProcessor {
 	sm := &BlockProcessor{
 		db:       db,
 		mem:      make(map[string]*big.Int),
-		Pow:      ezp.New(),
+		Pow:      pow,
 		bc:       chainManager,
 		eventMux: eventMux,
 		txpool:   txpool,
@@ -105,6 +104,9 @@ func (self *BlockProcessor) ApplyTransaction(coinbase *state.StateObject, stated
 
 	return receipt, txGas, err
 }
+func (self *BlockProcessor) ChainManager() *ChainManager {
+	return self.bc
+}
 
 func (self *BlockProcessor) ApplyTransactions(coinbase *state.StateObject, statedb *state.StateDB, block *types.Block, txs types.Transactions, transientProcess bool) (types.Receipts, types.Transactions, types.Transactions, types.Transactions, error) {
 	var (
@@ -256,6 +258,11 @@ func (sm *BlockProcessor) ValidateBlock(block, parent *types.Block) error {
 		return fmt.Errorf("GasLimit check failed for block %v (%v > %v)", block.Header().GasLimit, a, b)
 	}
 
+	// There can be at most one uncle
+	if len(block.Uncles()) > 1 {
+		return ValidationError("Block can only contain one uncle (contained %v)", len(block.Uncles()))
+	}
+
 	if block.Time() < parent.Time() {
 		return ValidationError("Block timestamp not after prev block (%v - %v)", block.Header().Time, parent.Header().Time)
 	}
diff --git a/core/chain_makers.go b/core/chain_makers.go
new file mode 100644
index 000000000..7afdfde0d
--- /dev/null
+++ b/core/chain_makers.go
@@ -0,0 +1,142 @@
+package core
+
+import (
+	"fmt"
+	"math/big"
+
+	"github.com/ethereum/go-ethereum/core/types"
+	"github.com/ethereum/go-ethereum/ethutil"
+	"github.com/ethereum/go-ethereum/event"
+	"github.com/ethereum/go-ethereum/pow"
+	"github.com/ethereum/go-ethereum/state"
+)
+
+// So we can generate blocks easily
+type FakePow struct{}
+
+func (f FakePow) Search(block pow.Block, stop <-chan struct{}) ([]byte, []byte, []byte) {
+	return nil, nil, nil
+}
+func (f FakePow) Verify(block pow.Block) bool { return true }
+func (f FakePow) GetHashrate() int64          { return 0 }
+func (f FakePow) Turbo(bool)                  {}
+
+// So we can deterministically seed different blockchains
+var (
+	CanonicalSeed = 1
+	ForkSeed      = 2
+)
+
+// Utility functions for making chains on the fly
+// Exposed for sake of testing from other packages (eg. go-ethash)
+func NewBlockFromParent(addr []byte, parent *types.Block) *types.Block {
+	return newBlockFromParent(addr, parent)
+}
+
+func MakeBlock(bman *BlockProcessor, parent *types.Block, i int, db ethutil.Database, seed int) *types.Block {
+	return makeBlock(bman, parent, i, db, seed)
+}
+
+func MakeChain(bman *BlockProcessor, parent *types.Block, max int, db ethutil.Database, seed int) types.Blocks {
+	return makeChain(bman, parent, max, db, seed)
+}
+
+func NewChainMan(block *types.Block, eventMux *event.TypeMux, db ethutil.Database) *ChainManager {
+	return newChainManager(block, eventMux, db)
+}
+
+func NewBlockProc(db ethutil.Database, txpool *TxPool, cman *ChainManager, eventMux *event.TypeMux) *BlockProcessor {
+	return newBlockProcessor(db, txpool, cman, eventMux)
+}
+
+func NewCanonical(n int, db ethutil.Database) (*BlockProcessor, error) {
+	return newCanonical(n, db)
+}
+
+// block time is fixed at 10 seconds
+func newBlockFromParent(addr []byte, parent *types.Block) *types.Block {
+	block := types.NewBlock(parent.Hash(), addr, parent.Root(), ethutil.BigPow(2, 32), nil, "")
+	block.SetUncles(nil)
+	block.SetTransactions(nil)
+	block.SetReceipts(nil)
+
+	header := block.Header()
+	header.Difficulty = CalcDifficulty(block, parent)
+	header.Number = new(big.Int).Add(parent.Header().Number, ethutil.Big1)
+	header.Time = parent.Header().Time + 10
+	header.GasLimit = CalcGasLimit(parent, block)
+
+	block.Td = parent.Td
+
+	return block
+}
+
+// Actually make a block by simulating what miner would do
+// we seed chains by the first byte of the coinbase
+func makeBlock(bman *BlockProcessor, parent *types.Block, i int, db ethutil.Database, seed int) *types.Block {
+	addr := ethutil.LeftPadBytes([]byte{byte(i)}, 20)
+	addr[0] = byte(seed)
+	block := newBlockFromParent(addr, parent)
+	state := state.New(block.Root(), db)
+	cbase := state.GetOrNewStateObject(addr)
+	cbase.SetGasPool(CalcGasLimit(parent, block))
+	cbase.AddBalance(BlockReward)
+	state.Update(ethutil.Big0)
+	block.SetRoot(state.Root())
+	return block
+}
+
+// Make a chain with real blocks
+// Runs ProcessWithParent to get proper state roots
+func makeChain(bman *BlockProcessor, parent *types.Block, max int, db ethutil.Database, seed int) types.Blocks {
+	bman.bc.currentBlock = parent
+	blocks := make(types.Blocks, max)
+	for i := 0; i < max; i++ {
+		block := makeBlock(bman, parent, i, db, seed)
+		td, err := bman.processWithParent(block, parent)
+		if err != nil {
+			fmt.Println("process with parent failed", err)
+			panic(err)
+		}
+		block.Td = td
+		blocks[i] = block
+		parent = block
+	}
+	return blocks
+}
+
+// Create a new chain manager starting from given block
+// Effectively a fork factory
+func newChainManager(block *types.Block, eventMux *event.TypeMux, db ethutil.Database) *ChainManager {
+	bc := &ChainManager{db: db, genesisBlock: GenesisBlock(db), eventMux: eventMux}
+	if block == nil {
+		bc.Reset()
+	} else {
+		bc.currentBlock = block
+		bc.td = block.Td
+	}
+	return bc
+}
+
+// block processor with fake pow
+func newBlockProcessor(db ethutil.Database, txpool *TxPool, cman *ChainManager, eventMux *event.TypeMux) *BlockProcessor {
+	bman := NewBlockProcessor(db, FakePow{}, txpool, newChainManager(nil, eventMux, db), eventMux)
+	return bman
+}
+
+// Make a new, deterministic canonical chain by running InsertChain
+// on result of makeChain
+func newCanonical(n int, db ethutil.Database) (*BlockProcessor, error) {
+	eventMux := &event.TypeMux{}
+	txpool := NewTxPool(eventMux)
+
+	bman := newBlockProcessor(db, txpool, newChainManager(nil, eventMux, db), eventMux)
+	bman.bc.SetProcessor(bman)
+	parent := bman.bc.CurrentBlock()
+	if n == 0 {
+		return bman, nil
+	}
+	lchain := makeChain(bman, parent, n, db, CanonicalSeed)
+	err := bman.bc.InsertChain(lchain)
+	return bman, err
+}
diff --git a/core/chain_manager_test.go b/core/chain_manager_test.go
index bc3a264d1..b562b677d 100644
--- a/core/chain_manager_test.go
+++ b/core/chain_manager_test.go
@@ -3,6 +3,7 @@ package core
 import (
 	"bytes"
 	"fmt"
+	"math/big"
 	"os"
 	"path"
 	"runtime"
@@ -21,6 +22,75 @@ func init() {
 	ethutil.ReadConfig("/tmp/ethtest", "/tmp/ethtest", "ETH")
 }
 
+// Test fork of length N starting from block i
+func testFork(t *testing.T, bman *BlockProcessor, i, N int, f func(td1, td2 *big.Int)) {
+	// switch databases to process the new chain
+	db, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	// copy old chain up to i into new db with deterministic canonical
+	bman2, err := newCanonical(i, db)
+	if err != nil {
+		t.Fatal("could not make new canonical in testFork", err)
+	}
+	// asert the bmans have the same block at i
+	bi1 := bman.bc.GetBlockByNumber(uint64(i)).Hash()
+	bi2 := bman2.bc.GetBlockByNumber(uint64(i)).Hash()
+	if bytes.Compare(bi1, bi2) != 0 {
+		t.Fatal("chains do not have the same hash at height", i)
+	}
+
+	bman2.bc.SetProcessor(bman2)
+
+	// extend the fork
+	parent := bman2.bc.CurrentBlock()
+	chainB := makeChain(bman2, parent, N, db, ForkSeed)
+	err = bman2.bc.InsertChain(chainB)
+	if err != nil {
+		t.Fatal("Insert chain error for fork:", err)
+	}
+
+	tdpre := bman.bc.Td()
+	// Test the fork's blocks on the original chain
+	td, err := testChain(chainB, bman)
+	if err != nil {
+		t.Fatal("expected chainB not to give errors:", err)
+	}
+	// Compare difficulties
+	f(tdpre, td)
+}
+
+func printChain(bc *ChainManager) {
+	for i := bc.CurrentBlock().Number().Uint64(); i > 0; i-- {
+		b := bc.GetBlockByNumber(uint64(i))
+		fmt.Printf("\t%x\n", b.Hash())
+	}
+}
+
+// process blocks against a chain
+func testChain(chainB types.Blocks, bman *BlockProcessor) (*big.Int, error) {
+	td := new(big.Int)
+	for _, block := range chainB {
+		td2, err := bman.bc.processor.Process(block)
+		if err != nil {
+			if IsKnownBlockErr(err) {
+				continue
+			}
+			return nil, err
+		}
+		block.Td = td2
+		td = td2
+
+		bman.bc.mu.Lock()
+		{
+			bman.bc.write(block)
+		}
+		bman.bc.mu.Unlock()
+	}
+	return td, nil
+}
+
 func loadChain(fn string, t *testing.T) (types.Blocks, error) {
 	fh, err := os.OpenFile(path.Join(os.Getenv("GOPATH"), "src", "github.com", "ethereum", "go-ethereum", "_data", fn), os.O_RDONLY, os.ModePerm)
 	if err != nil {
@@ -45,6 +115,130 @@ func insertChain(done chan bool, chainMan *ChainManager, chain types.Blocks, t *
 	done <- true
 }
 
+func TestExtendCanonical(t *testing.T) {
+	CanonicalLength := 5
+	db, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	// make first chain starting from genesis
+	bman, err := newCanonical(CanonicalLength, db)
+	if err != nil {
+		t.Fatal("Could not make new canonical chain:", err)
+	}
+	f := func(td1, td2 *big.Int) {
+		if td2.Cmp(td1) <= 0 {
+			t.Error("expected chainB to have higher difficulty. Got", td2, "expected more than", td1)
+		}
+	}
+	// Start fork from current height (CanonicalLength)
+	testFork(t, bman, CanonicalLength, 1, f)
+	testFork(t, bman, CanonicalLength, 2, f)
+	testFork(t, bman, CanonicalLength, 5, f)
+	testFork(t, bman, CanonicalLength, 10, f)
+}
+
+func TestShorterFork(t *testing.T) {
+	db, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	// make first chain starting from genesis
+	bman, err := newCanonical(10, db)
+	if err != nil {
+		t.Fatal("Could not make new canonical chain:", err)
+	}
+	f := func(td1, td2 *big.Int) {
+		if td2.Cmp(td1) >= 0 {
+			t.Error("expected chainB to have lower difficulty. Got", td2, "expected less than", td1)
+		}
+	}
+	// Sum of numbers must be less than 10
+	// for this to be a shorter fork
+	testFork(t, bman, 0, 3, f)
+	testFork(t, bman, 0, 7, f)
+	testFork(t, bman, 1, 1, f)
+	testFork(t, bman, 1, 7, f)
+	testFork(t, bman, 5, 3, f)
+	testFork(t, bman, 5, 4, f)
+}
+
+func TestLongerFork(t *testing.T) {
+	db, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	// make first chain starting from genesis
+	bman, err := newCanonical(10, db)
+	if err != nil {
+		t.Fatal("Could not make new canonical chain:", err)
+	}
+	f := func(td1, td2 *big.Int) {
+		if td2.Cmp(td1) <= 0 {
+			t.Error("expected chainB to have higher difficulty. Got", td2, "expected more than", td1)
+		}
+	}
+	// Sum of numbers must be greater than 10
+	// for this to be a longer fork
+	testFork(t, bman, 0, 11, f)
+	testFork(t, bman, 0, 15, f)
+	testFork(t, bman, 1, 10, f)
+	testFork(t, bman, 1, 12, f)
+	testFork(t, bman, 5, 6, f)
+	testFork(t, bman, 5, 8, f)
+}
+
+func TestEqualFork(t *testing.T) {
+	db, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	bman, err := newCanonical(10, db)
+	if err != nil {
+		t.Fatal("Could not make new canonical chain:", err)
+	}
+	f := func(td1, td2 *big.Int) {
+		if td2.Cmp(td1) != 0 {
+			t.Error("expected chainB to have equal difficulty. Got", td2, "expected ", td1)
+		}
+	}
+	// Sum of numbers must be equal to 10
+	// for this to be an equal fork
+	testFork(t, bman, 0, 10, f)
+	testFork(t, bman, 1, 9, f)
+	testFork(t, bman, 2, 8, f)
+	testFork(t, bman, 5, 5, f)
+	testFork(t, bman, 6, 4, f)
+	testFork(t, bman, 9, 1, f)
+}
+
+func TestBrokenChain(t *testing.T) {
+	db, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	bman, err := newCanonical(10, db)
+	if err != nil {
+		t.Fatal("Could not make new canonical chain:", err)
+	}
+	db2, err := ethdb.NewMemDatabase()
+	if err != nil {
+		t.Fatal("Failed to create db:", err)
+	}
+	bman2, err := newCanonical(10, db2)
+	if err != nil {
+		t.Fatal("Could not make new canonical chain:", err)
+	}
+	bman2.bc.SetProcessor(bman2)
+	parent := bman2.bc.CurrentBlock()
+	chainB := makeChain(bman2, parent, 5, db2, ForkSeed)
+	chainB = chainB[1:]
+	_, err = testChain(chainB, bman)
+	if err == nil {
+		t.Error("expected broken chain to return error")
+	}
+}
+
 func TestChainInsertions(t *testing.T) {
 	t.Skip() // travil fails.
 
diff --git a/core/transaction_pool.go b/core/transaction_pool.go
index 050cff3d8..bd377f679 100644
--- a/core/transaction_pool.go
+++ b/core/transaction_pool.go
@@ -117,8 +117,13 @@ func (self *TxPool) add(tx *types.Transaction) error {
 	} else {
 		to = "[NEW_CONTRACT]"
 	}
-
-	txplogger.Debugf("(t) %x => %s (%v) %x\n", tx.From()[:4], to, tx.Value, tx.Hash())
+	var from string
+	if len(tx.From()) > 0 {
+		from = ethutil.Bytes2Hex(tx.From()[:4])
+	} else {
+		return errors.New(fmt.Sprintf("FROM ADDRESS MUST BE POSITIVE (was %v)", tx.From()))
+	}
+	txplogger.Debugf("(t) %x => %s (%v) %x\n", from, to, tx.Value, tx.Hash())
 
 	// Notify the subscribers
 	go self.eventMux.Post(TxPreEvent{tx})
diff --git a/core/types/block.go b/core/types/block.go
index d57de1311..673c72003 100644
--- a/core/types/block.go
+++ b/core/types/block.go
@@ -41,12 +41,29 @@ type Header struct {
 	Extra string
 	// Block Nonce for verification
 	Nonce ethutil.Bytes
+	// Mix digest for quick checking to prevent DOS
+	MixDigest ethutil.Bytes
+	// SeedHash used for light client verification
+	SeedHash ethutil.Bytes
 }
 
 func (self *Header) rlpData(withNonce bool) []interface{} {
-	fields := []interface{}{self.ParentHash, self.UncleHash, self.Coinbase, self.Root, self.TxHash, self.ReceiptHash, self.Bloom, self.Difficulty, self.Number, self.GasLimit, self.GasUsed, self.Time, self.Extra}
+	fields := []interface{}{
+		self.ParentHash,
+		self.UncleHash,
+		self.Coinbase,
+		self.Root,
+		self.TxHash,
+		self.ReceiptHash,
+		self.Bloom,
+		self.Difficulty,
+		self.Number,
+		self.GasLimit,
+		self.GasUsed,
+		self.Time,
+		self.Extra}
 	if withNonce {
-		fields = append(fields, self.Nonce)
+		fields = append(fields, self.Nonce, self.MixDigest, self.SeedHash)
 	}
 
 	return fields
@@ -176,6 +193,8 @@ func (self *Block) RlpDataForStorage() interface{} {
 // Header accessors (add as you need them)
 func (self *Block) Number() *big.Int          { return self.header.Number }
 func (self *Block) NumberU64() uint64         { return self.header.Number.Uint64() }
+func (self *Block) MixDigest() []byte         { return self.header.MixDigest }
+func (self *Block) SeedHash() []byte          { return self.header.SeedHash }
 func (self *Block) Nonce() []byte             { return self.header.Nonce }
 func (self *Block) Bloom() []byte             { return self.header.Bloom }
 func (self *Block) Coinbase() []byte          { return self.header.Coinbase }
@@ -200,7 +219,6 @@ func (self *Block) GetUncle(i int) *Header {
 
 // Implement pow.Block
 func (self *Block) Difficulty() *big.Int { return self.header.Difficulty }
-func (self *Block) N() []byte            { return self.header.Nonce }
 func (self *Block) HashNoNonce() []byte  { return self.header.HashNoNonce() }
 
 func (self *Block) Hash() []byte {
@@ -250,7 +268,10 @@ func (self *Header) String() string {
 	Time:		    %v
 	Extra:		    %v
 	Nonce:		    %x
-`, self.ParentHash, self.UncleHash, self.Coinbase, self.Root, self.TxHash, self.ReceiptHash, self.Bloom, self.Difficulty, self.Number, self.GasLimit, self.GasUsed, self.Time, self.Extra, self.Nonce)
+	MixDigest:          %x
+	SeedHash:           %x
+
+`, self.ParentHash, self.UncleHash, self.Coinbase, self.Root, self.TxHash, self.ReceiptHash, self.Bloom, self.Difficulty, self.Number, self.GasLimit, self.GasUsed, self.Time, self.Extra, self.Nonce, self.MixDigest, self.SeedHash)
 }
 
 type Blocks []*Block